/* * Copyright (c) 2005-2007 Chelsio, Inc. All rights reserved. * * This software is available to you under a choice of one of two * licenses. You may choose to be licensed under the terms of the GNU * General Public License (GPL) Version 2, available from the file * COPYING in the main directory of this source tree, or the * OpenIB.org BSD license below: * * Redistribution and use in source and binary forms, with or * without modification, are permitted provided that the following * conditions are met: * * - Redistributions of source code must retain the above * copyright notice, this list of conditions and the following * disclaimer. * * - Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials * provided with the distribution. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. */ #include <linux/skbuff.h> #include <linux/netdevice.h> #include <linux/etherdevice.h> #include <linux/if_vlan.h> #include <linux/ip.h> #include <linux/tcp.h> #include <linux/dma-mapping.h> #include "common.h" #include "regs.h" #include "sge_defs.h" #include "t3_cpl.h" #include "firmware_exports.h" #define USE_GTS 0 #define SGE_RX_SM_BUF_SIZE 1536 /* * If USE_RX_PAGE is defined, the small freelist populated with (partial) * pages instead of skbs. Pages are carved up into RX_PAGE_SIZE chunks (must * be a multiple of the host page size). */ #define USE_RX_PAGE #define RX_PAGE_SIZE 2048 /* * skb freelist packets are copied into a new skb (and the freelist one is * reused) if their len is <= */ #define SGE_RX_COPY_THRES 256 /* * Minimum number of freelist entries before we start dropping TUNNEL frames. */ #define SGE_RX_DROP_THRES 16 /* * Period of the Tx buffer reclaim timer. This timer does not need to run * frequently as Tx buffers are usually reclaimed by new Tx packets. */ #define TX_RECLAIM_PERIOD (HZ / 4) /* WR size in bytes */ #define WR_LEN (WR_FLITS * 8) /* * Types of Tx queues in each queue set. Order here matters, do not change. */ enum { TXQ_ETH, TXQ_OFLD, TXQ_CTRL }; /* Values for sge_txq.flags */ enum { TXQ_RUNNING = 1 << 0, /* fetch engine is running */ TXQ_LAST_PKT_DB = 1 << 1, /* last packet rang the doorbell */ }; struct tx_desc { u64 flit[TX_DESC_FLITS]; }; struct rx_desc { __be32 addr_lo; __be32 len_gen; __be32 gen2; __be32 addr_hi; }; struct tx_sw_desc { /* SW state per Tx descriptor */ struct sk_buff *skb; }; struct rx_sw_desc { /* SW state per Rx descriptor */ union { struct sk_buff *skb; struct sge_fl_page page; } t; DECLARE_PCI_UNMAP_ADDR(dma_addr); }; struct rsp_desc { /* response queue descriptor */ struct rss_header rss_hdr; __be32 flags; __be32 len_cq; u8 imm_data[47]; u8 intr_gen; }; struct unmap_info { /* packet unmapping info, overlays skb->cb */ int sflit; /* start flit of first SGL entry in Tx descriptor */ u16 fragidx; /* first page fragment in current Tx descriptor */ u16 addr_idx; /* buffer index of first SGL entry in descriptor */ u32 len; /* mapped length of skb main body */ }; /* * Holds unmapping information for Tx packets that need deferred unmapping. * This structure lives at skb->head and must be allocated by callers. */ struct deferred_unmap_info { struct pci_dev *pdev; dma_addr_t addr[MAX_SKB_FRAGS + 1]; }; /* * Maps a number of flits to the number of Tx descriptors that can hold them. * The formula is * * desc = 1 + (flits - 2) / (WR_FLITS - 1). * * HW allows up to 4 descriptors to be combined into a WR. */ static u8 flit_desc_map[] = { 0, #if SGE_NUM_GENBITS == 1 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4 #elif SGE_NUM_GENBITS == 2 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, #else # error "SGE_NUM_GENBITS must be 1 or 2" #endif }; static inline struct sge_qset *fl_to_qset(const struct sge_fl *q, int qidx) { return container_of(q, struct sge_qset, fl[qidx]); } static inline struct sge_qset *rspq_to_qset(const struct sge_rspq *q) { return container_of(q, struct sge_qset, rspq); } static inline struct sge_qset *txq_to_qset(const struct sge_txq *q, int qidx) { return container_of(q, struct sge_qset, txq[qidx]); } /** * refill_rspq - replenish an SGE response queue * @adapter: the adapter * @q: the response queue to replenish * @credits: how many new responses to make available * * Replenishes a response queue by making the supplied number of responses * available to HW. */ static inline void refill_rspq(struct adapter *adapter, const struct sge_rspq *q, unsigned int credits) { t3_write_reg(adapter, A_SG_RSPQ_CREDIT_RETURN, V_RSPQ(q->cntxt_id) | V_CREDITS(credits)); } /** * need_skb_unmap - does the platform need unmapping of sk_buffs? * * Returns true if the platfrom needs sk_buff unmapping. The compiler * optimizes away unecessary code if this returns true. */ static inline int need_skb_unmap(void) { /* * This structure is used to tell if the platfrom needs buffer * unmapping by checking if DECLARE_PCI_UNMAP_ADDR defines anything. */ struct dummy { DECLARE_PCI_UNMAP_ADDR(addr); }; return sizeof(struct dummy) != 0; } /** * unmap_skb - unmap a packet main body and its page fragments * @skb: the packet * @q: the Tx queue containing Tx descriptors for the packet * @cidx: index of Tx descriptor * @pdev: the PCI device * * Unmap the main body of an sk_buff and its page fragments, if any. * Because of the fairly complicated structure of our SGLs and the desire * to conserve space for metadata, we keep the information necessary to * unmap an sk_buff partly in the sk_buff itself (in its cb), and partly * in the Tx descriptors (the physical addresses of the various data * buffers). The send functions initialize the state in skb->cb so we * can unmap the buffers held in the first Tx descriptor here, and we * have enough information at this point to update the state for the next * Tx descriptor. */ static inline void unmap_skb(struct sk_buff *skb, struct sge_txq *q, unsigned int cidx, struct pci_dev *pdev) { const struct sg_ent *sgp; struct unmap_info *ui = (struct unmap_info *)skb->cb; int nfrags, frag_idx, curflit, j = ui->addr_idx; sgp = (struct sg_ent *)&q->desc[cidx].flit[ui->sflit]; if (ui->len) { pci_unmap_single(pdev, be64_to_cpu(sgp->addr[0]), ui->len, PCI_DMA_TODEVICE); ui->len = 0; /* so we know for next descriptor for this skb */ j = 1; } frag_idx = ui->fragidx; curflit = ui->sflit + 1 + j; nfrags = skb_shinfo(skb)->nr_frags; while (frag_idx < nfrags && curflit < WR_FLITS) { pci_unmap_page(pdev, be64_to_cpu(sgp->addr[j]), skb_shinfo(skb)->frags[frag_idx].size, PCI_DMA_TODEVICE); j ^= 1; if (j == 0) { sgp++; curflit++; } curflit++; frag_idx++; } if (frag_idx < nfrags) { /* SGL continues into next Tx descriptor */ ui->fragidx = frag_idx; ui->addr_idx = j; ui->sflit = curflit - WR_FLITS - j; /* sflit can be -1 */ } } /** * free_tx_desc - reclaims Tx descriptors and their buffers * @adapter: the adapter * @q: the Tx queue to reclaim descriptors from * @n: the number of descriptors to reclaim * * Reclaims Tx descriptors from an SGE Tx queue and frees the associated * Tx buffers. Called with the Tx queue lock held. */ static void free_tx_desc(struct adapter *adapter, struct sge_txq *q, unsigned int n) { struct tx_sw_desc *d; struct pci_dev *pdev = adapter->pdev; unsigned int cidx = q->cidx; const int need_unmap = need_skb_unmap() && q->cntxt_id >= FW_TUNNEL_SGEEC_START; d = &q->sdesc[cidx]; while (n--) { if (d->skb) { /* an SGL is present */ if (need_unmap) unmap_skb(d->skb, q, cidx, pdev); if (d->skb->priority == cidx) kfree_skb(d->skb); } ++d; if (++cidx == q->size) { cidx = 0; d = q->sdesc; } } q->cidx = cidx; } /** * reclaim_completed_tx - reclaims completed Tx descriptors * @adapter: the adapter * @q: the Tx queue to reclaim completed descriptors from * * Reclaims Tx descriptors that the SGE has indicated it has processed, * and frees the associated buffers if possible. Called with the Tx * queue's lock held. */ static inline void reclaim_completed_tx(struct adapter *adapter, struct sge_txq *q) { unsigned int reclaim = q->processed - q->cleaned; if (reclaim) { free_tx_desc(adapter, q, reclaim); q->cleaned += reclaim; q->in_use -= reclaim; } } /** * should_restart_tx - are there enough resources to restart a Tx queue? * @q: the Tx queue * * Checks if there are enough descriptors to restart a suspended Tx queue. */ static inline int should_restart_tx(const struct sge_txq *q) { unsigned int r = q->processed - q->cleaned; return q->in_use - r < (q->size >> 1); } /** * free_rx_bufs - free the Rx buffers on an SGE free list * @pdev: the PCI device associated with the adapter * @rxq: the SGE free list to clean up * * Release the buffers on an SGE free-buffer Rx queue. HW fetching from * this queue should be stopped before calling this function. */ static void free_rx_bufs(struct pci_dev *pdev, struct sge_fl *q) { unsigned int cidx = q->cidx; while (q->credits--) { struct rx_sw_desc *d = &q->sdesc[cidx]; pci_unmap_single(pdev, pci_unmap_addr(d, dma_addr), q->buf_size, PCI_DMA_FROMDEVICE); if (q->buf_size != RX_PAGE_SIZE) { kfree_skb(d->t.skb); d->t.skb = NULL; } else { if (d->t.page.frag.page) put_page(d->t.page.frag.page); d->t.page.frag.page = NULL; } if (++cidx == q->size) cidx = 0; } if (q->page.frag.page) put_page(q->page.frag.page); q->page.frag.page = NULL; } /** * add_one_rx_buf - add a packet buffer to a free-buffer list * @va: va of the buffer to add * @len: the buffer length * @d: the HW Rx descriptor to write * @sd: the SW Rx descriptor to write * @gen: the generation bit value * @pdev: the PCI device associated with the adapter * * Add a buffer of the given length to the supplied HW and SW Rx * descriptors. */ static inline void add_one_rx_buf(unsigned char *va, unsigned int len, struct rx_desc *d, struct rx_sw_desc *sd, unsigned int gen, struct pci_dev *pdev) { dma_addr_t mapping; mapping = pci_map_single(pdev, va, len, PCI_DMA_FROMDEVICE); pci_unmap_addr_set(sd, dma_addr, mapping); d->addr_lo = cpu_to_be32(mapping); d->addr_hi = cpu_to_be32((u64) mapping >> 32); wmb(); d->len_gen = cpu_to_be32(V_FLD_GEN1(gen)); d->gen2 = cpu_to_be32(V_FLD_GEN2(gen)); } /** * refill_fl - refill an SGE free-buffer list * @adapter: the adapter * @q: the free-list to refill * @n: the number of new buffers to allocate * @gfp: the gfp flags for allocating new buffers * * (Re)populate an SGE free-buffer list with up to @n new packet buffers, * allocated with the supplied gfp flags. The caller must assure that * @n does not exceed the queue's capacity. */ static void refill_fl(struct adapter *adap, struct sge_fl *q, int n, gfp_t gfp) { struct rx_sw_desc *sd = &q->sdesc[q->pidx]; struct rx_desc *d = &q->desc[q->pidx]; struct sge_fl_page *p = &q->page; while (n--) { unsigned char *va; if (unlikely(q->buf_size != RX_PAGE_SIZE)) { struct sk_buff *skb = alloc_skb(q->buf_size, gfp); if (!skb) { q->alloc_failed++; break; } va = skb->data; sd->t.skb = skb; } else { if (!p->frag.page) { p->frag.page = alloc_pages(gfp, 0); if (unlikely(!p->frag.page)) { q->alloc_failed++; break; } else { p->frag.size = RX_PAGE_SIZE; p->frag.page_offset = 0; p->va = page_address(p->frag.page); } } memcpy(&sd->t, p, sizeof(*p)); va = p->va; p->frag.page_offset += RX_PAGE_SIZE; BUG_ON(p->frag.page_offset > PAGE_SIZE); p->va += RX_PAGE_SIZE; if (p->frag.page_offset == PAGE_SIZE) p->frag.page = NULL; else get_page(p->frag.page); } add_one_rx_buf(va, q->buf_size, d, sd, q->gen, adap->pdev); d++; sd++; if (++q->pidx == q->size) { q->pidx = 0; q->gen ^= 1; sd = q->sdesc; d = q->desc; } q->credits++; } t3_write_reg(adap, A_SG_KDOORBELL, V_EGRCNTX(q->cntxt_id)); } static inline void __refill_fl(struct adapter *adap, struct sge_fl *fl) { refill_fl(adap, fl, min(16U, fl->size - fl->credits), GFP_ATOMIC); } /** * recycle_rx_buf - recycle a receive buffer * @adapter: the adapter * @q: the SGE free list * @idx: index of buffer to recycle * * Recycles the specified buffer on the given free list by adding it at * the next available slot on the list. */ static void recycle_rx_buf(struct adapter *adap, struct sge_fl *q, unsigned int idx) { struct rx_desc *from = &q->desc[idx]; struct rx_desc *to = &q->desc[q->pidx]; memcpy(&q->sdesc[q->pidx], &q->sdesc[idx], sizeof(struct rx_sw_desc)); to->addr_lo = from->addr_lo; /* already big endian */ to->addr_hi = from->addr_hi; /* likewise */ wmb(); to->len_gen = cpu_to_be32(V_FLD_GEN1(q->gen)); to->gen2 = cpu_to_be32(V_FLD_GEN2(q->gen)); q->credits++; if (++q->pidx == q->size) { q->pidx = 0; q->gen ^= 1; } t3_write_reg(adap, A_SG_KDOORBELL, V_EGRCNTX(q->cntxt_id)); } /** * alloc_ring - allocate resources for an SGE descriptor ring * @pdev: the PCI device * @nelem: the number of descriptors * @elem_size: the size of each descriptor * @sw_size: the size of the SW state associated with each ring element * @phys: the physical address of the allocated ring * @metadata: address of the array holding the SW state for the ring * * Allocates resources for an SGE descriptor ring, such as Tx queues, * free buffer lists, or response queues. Each SGE ring requires * space for its HW descriptors plus, optionally, space for the SW state * associated with each HW entry (the metadata). The function returns * three values: the virtual address for the HW ring (the return value * of the function), the physical address of the HW ring, and the address * of the SW ring. */ static void *alloc_ring(struct pci_dev *pdev, size_t nelem, size_t elem_size, size_t sw_size, dma_addr_t * phys, void *metadata) { size_t len = nelem * elem_size; void *s = NULL; void *p = dma_alloc_coherent(&pdev->dev, len, phys, GFP_KERNEL); if (!p) return NULL; if (sw_size) { s = kcalloc(nelem, sw_size, GFP_KERNEL); if (!s) { dma_free_coherent(&pdev->dev, len, p, *phys); return NULL; } } if (metadata) *(void **)metadata = s; memset(p, 0, len); return p; } /** * free_qset - free the resources of an SGE queue set * @adapter: the adapter owning the queue set * @q: the queue set * * Release the HW and SW resources associated with an SGE queue set, such * as HW contexts, packet buffers, and descriptor rings. Traffic to the * queue set must be quiesced prior to calling this. */ void t3_free_qset(struct adapter *adapter, struct sge_qset *q) { int i; struct pci_dev *pdev = adapter->pdev; if (q->tx_reclaim_timer.function) del_timer_sync(&q->tx_reclaim_timer); for (i = 0; i < SGE_RXQ_PER_SET; ++i) if (q->fl[i].desc) { spin_lock(&adapter->sge.reg_lock); t3_sge_disable_fl(adapter, q->fl[i].cntxt_id); spin_unlock(&adapter->sge.reg_lock); free_rx_bufs(pdev, &q->fl[i]); kfree(q->fl[i].sdesc); dma_free_coherent(&pdev->dev, q->fl[i].size * sizeof(struct rx_desc), q->fl[i].desc, q->fl[i].phys_addr); } for (i = 0; i < SGE_TXQ_PER_SET; ++i) if (q->txq[i].desc) { spin_lock(&adapter->sge.reg_lock); t3_sge_enable_ecntxt(adapter, q->txq[i].cntxt_id, 0); spin_unlock(&adapter->sge.reg_lock); if (q->txq[i].sdesc) { free_tx_desc(adapter, &q->txq[i], q->txq[i].in_use); kfree(q->txq[i].sdesc); } dma_free_coherent(&pdev->dev, q->txq[i].size * sizeof(struct tx_desc), q->txq[i].desc, q->txq[i].phys_addr); __skb_queue_purge(&q->txq[i].sendq); } if (q->rspq.desc) { spin_lock(&adapter->sge.reg_lock); t3_sge_disable_rspcntxt(adapter, q->rspq.cntxt_id); spin_unlock(&adapter->sge.reg_lock); dma_free_coherent(&pdev->dev, q->rspq.size * sizeof(struct rsp_desc), q->rspq.desc, q->rspq.phys_addr); } if (q->netdev) q->netdev->atalk_ptr = NULL; memset(q, 0, sizeof(*q)); } /** * init_qset_cntxt - initialize an SGE queue set context info * @qs: the queue set * @id: the queue set id * * Initializes the TIDs and context ids for the queues of a queue set. */ static void init_qset_cntxt(struct sge_qset *qs, unsigned int id) { qs->rspq.cntxt_id = id; qs->fl[0].cntxt_id = 2 * id; qs->fl[1].cntxt_id = 2 * id + 1; qs->txq[TXQ_ETH].cntxt_id = FW_TUNNEL_SGEEC_START + id; qs->txq[TXQ_ETH].token = FW_TUNNEL_TID_START + id; qs->txq[TXQ_OFLD].cntxt_id = FW_OFLD_SGEEC_START + id; qs->txq[TXQ_CTRL].cntxt_id = FW_CTRL_SGEEC_START + id; qs->txq[TXQ_CTRL].token = FW_CTRL_TID_START + id; } /** * sgl_len - calculates the size of an SGL of the given capacity * @n: the number of SGL entries * * Calculates the number of flits needed for a scatter/gather list that * can hold the given number of entries. */ static inline unsigned int sgl_len(unsigned int n) { /* alternatively: 3 * (n / 2) + 2 * (n & 1) */ return (3 * n) / 2 + (n & 1); } /** * flits_to_desc - returns the num of Tx descriptors for the given flits * @n: the number of flits * * Calculates the number of Tx descriptors needed for the supplied number * of flits. */ static inline unsigned int flits_to_desc(unsigned int n) { BUG_ON(n >= ARRAY_SIZE(flit_desc_map)); return flit_desc_map[n]; } /** * get_imm_packet - return the next ingress packet buffer from a response * @resp: the response descriptor containing the packet data * * Return a packet containing the immediate data of the given response. */ static inline struct sk_buff *get_imm_packet(const struct rsp_desc *resp) { struct sk_buff *skb = alloc_skb(IMMED_PKT_SIZE, GFP_ATOMIC); if (skb) { __skb_put(skb, IMMED_PKT_SIZE); memcpy(skb->data, resp->imm_data, IMMED_PKT_SIZE); } return skb; } /** * calc_tx_descs - calculate the number of Tx descriptors for a packet * @skb: the packet * * Returns the number of Tx descriptors needed for the given Ethernet * packet. Ethernet packets require addition of WR and CPL headers. */ static inline unsigned int calc_tx_descs(const struct sk_buff *skb) { unsigned int flits; if (skb->len <= WR_LEN - sizeof(struct cpl_tx_pkt)) return 1; flits = sgl_len(skb_shinfo(skb)->nr_frags + 1) + 2; if (skb_shinfo(skb)->gso_size) flits++; return flits_to_desc(flits); } /** * make_sgl - populate a scatter/gather list for a packet * @skb: the packet * @sgp: the SGL to populate * @start: start address of skb main body data to include in the SGL * @len: length of skb main body data to include in the SGL * @pdev: the PCI device * * Generates a scatter/gather list for the buffers that make up a packet * and returns the SGL size in 8-byte words. The caller must size the SGL * appropriately. */ static inline unsigned int make_sgl(const struct sk_buff *skb, struct sg_ent *sgp, unsigned char *start, unsigned int len, struct pci_dev *pdev) { dma_addr_t mapping; unsigned int i, j = 0, nfrags; if (len) { mapping = pci_map_single(pdev, start, len, PCI_DMA_TODEVICE); sgp->len[0] = cpu_to_be32(len); sgp->addr[0] = cpu_to_be64(mapping); j = 1; } nfrags = skb_shinfo(skb)->nr_frags; for (i = 0; i < nfrags; i++) { skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; mapping = pci_map_page(pdev, frag->page, frag->page_offset, frag->size, PCI_DMA_TODEVICE); sgp->len[j] = cpu_to_be32(frag->size); sgp->addr[j] = cpu_to_be64(mapping); j ^= 1; if (j == 0) ++sgp; } if (j) sgp->len[j] = 0; return ((nfrags + (len != 0)) * 3) / 2 + j; } /** * check_ring_tx_db - check and potentially ring a Tx queue's doorbell * @adap: the adapter * @q: the Tx queue * * Ring the doorbel if a Tx queue is asleep. There is a natural race, * where the HW is going to sleep just after we checked, however, * then the interrupt handler will detect the outstanding TX packet * and ring the doorbell for us. * * When GTS is disabled we unconditionally ring the doorbell. */ static inline void check_ring_tx_db(struct adapter *adap, struct sge_txq *q) { #if USE_GTS clear_bit(TXQ_LAST_PKT_DB, &q->flags); if (test_and_set_bit(TXQ_RUNNING, &q->flags) == 0) { set_bit(TXQ_LAST_PKT_DB, &q->flags); t3_write_reg(adap, A_SG_KDOORBELL, F_SELEGRCNTX | V_EGRCNTX(q->cntxt_id)); } #else wmb(); /* write descriptors before telling HW */ t3_write_reg(adap, A_SG_KDOORBELL, F_SELEGRCNTX | V_EGRCNTX(q->cntxt_id)); #endif } static inline void wr_gen2(struct tx_desc *d, unsigned int gen) { #if SGE_NUM_GENBITS == 2 d->flit[TX_DESC_FLITS - 1] = cpu_to_be64(gen); #endif } /** * write_wr_hdr_sgl - write a WR header and, optionally, SGL * @ndesc: number of Tx descriptors spanned by the SGL * @skb: the packet corresponding to the WR * @d: first Tx descriptor to be written * @pidx: index of above descriptors * @q: the SGE Tx queue * @sgl: the SGL * @flits: number of flits to the start of the SGL in the first descriptor * @sgl_flits: the SGL size in flits * @gen: the Tx descriptor generation * @wr_hi: top 32 bits of WR header based on WR type (big endian) * @wr_lo: low 32 bits of WR header based on WR type (big endian) * * Write a work request header and an associated SGL. If the SGL is * small enough to fit into one Tx descriptor it has already been written * and we just need to write the WR header. Otherwise we distribute the * SGL across the number of descriptors it spans. */ static void write_wr_hdr_sgl(unsigned int ndesc, struct sk_buff *skb, struct tx_desc *d, unsigned int pidx, const struct sge_txq *q, const struct sg_ent *sgl, unsigned int flits, unsigned int sgl_flits, unsigned int gen, unsigned int wr_hi, unsigned int wr_lo) { struct work_request_hdr *wrp = (struct work_request_hdr *)d; struct tx_sw_desc *sd = &q->sdesc[pidx]; sd->skb = skb; if (need_skb_unmap()) { struct unmap_info *ui = (struct unmap_info *)skb->cb; ui->fragidx = 0; ui->addr_idx = 0; ui->sflit = flits; } if (likely(ndesc == 1)) { skb->priority = pidx; wrp->wr_hi = htonl(F_WR_SOP | F_WR_EOP | V_WR_DATATYPE(1) | V_WR_SGLSFLT(flits)) | wr_hi; wmb(); wrp->wr_lo = htonl(V_WR_LEN(flits + sgl_flits) | V_WR_GEN(gen)) | wr_lo; wr_gen2(d, gen); } else { unsigned int ogen = gen; const u64 *fp = (const u64 *)sgl; struct work_request_hdr *wp = wrp; wrp->wr_hi = htonl(F_WR_SOP | V_WR_DATATYPE(1) | V_WR_SGLSFLT(flits)) | wr_hi; while (sgl_flits) { unsigned int avail = WR_FLITS - flits; if (avail > sgl_flits) avail = sgl_flits; memcpy(&d->flit[flits], fp, avail * sizeof(*fp)); sgl_flits -= avail; ndesc--; if (!sgl_flits) break; fp += avail; d++; sd++; if (++pidx == q->size) { pidx = 0; gen ^= 1; d = q->desc; sd = q->sdesc; } sd->skb = skb; wrp = (struct work_request_hdr *)d; wrp->wr_hi = htonl(V_WR_DATATYPE(1) | V_WR_SGLSFLT(1)) | wr_hi; wrp->wr_lo = htonl(V_WR_LEN(min(WR_FLITS, sgl_flits + 1)) | V_WR_GEN(gen)) | wr_lo; wr_gen2(d, gen); flits = 1; } skb->priority = pidx; wrp->wr_hi |= htonl(F_WR_EOP); wmb(); wp->wr_lo = htonl(V_WR_LEN(WR_FLITS) | V_WR_GEN(ogen)) | wr_lo; wr_gen2((struct tx_desc *)wp, ogen); WARN_ON(ndesc != 0); } } /** * write_tx_pkt_wr - write a TX_PKT work request * @adap: the adapter * @skb: the packet to send * @pi: the egress interface * @pidx: index of the first Tx descriptor to write * @gen: the generation value to use * @q: the Tx queue * @ndesc: number of descriptors the packet will occupy * @compl: the value of the COMPL bit to use * * Generate a TX_PKT work request to send the supplied packet. */ static void write_tx_pkt_wr(struct adapter *adap, struct sk_buff *skb, const struct port_info *pi, unsigned int pidx, unsigned int gen, struct sge_txq *q, unsigned int ndesc, unsigned int compl) { unsigned int flits, sgl_flits, cntrl, tso_info; struct sg_ent *sgp, sgl[MAX_SKB_FRAGS / 2 + 1]; struct tx_desc *d = &q->desc[pidx]; struct cpl_tx_pkt *cpl = (struct cpl_tx_pkt *)d; cpl->len = htonl(skb->len | 0x80000000); cntrl = V_TXPKT_INTF(pi->port_id); if (vlan_tx_tag_present(skb) && pi->vlan_grp) cntrl |= F_TXPKT_VLAN_VLD | V_TXPKT_VLAN(vlan_tx_tag_get(skb)); tso_info = V_LSO_MSS(skb_shinfo(skb)->gso_size); if (tso_info) { int eth_type; struct cpl_tx_pkt_lso *hdr = (struct cpl_tx_pkt_lso *)cpl; d->flit[2] = 0; cntrl |= V_TXPKT_OPCODE(CPL_TX_PKT_LSO); hdr->cntrl = htonl(cntrl); eth_type = skb->nh.raw - skb->data == ETH_HLEN ? CPL_ETH_II : CPL_ETH_II_VLAN; tso_info |= V_LSO_ETH_TYPE(eth_type) | V_LSO_IPHDR_WORDS(skb->nh.iph->ihl) | V_LSO_TCPHDR_WORDS(skb->h.th->doff); hdr->lso_info = htonl(tso_info); flits = 3; } else { cntrl |= V_TXPKT_OPCODE(CPL_TX_PKT); cntrl |= F_TXPKT_IPCSUM_DIS; /* SW calculates IP csum */ cntrl |= V_TXPKT_L4CSUM_DIS(skb->ip_summed != CHECKSUM_PARTIAL); cpl->cntrl = htonl(cntrl); if (skb->len <= WR_LEN - sizeof(*cpl)) { q->sdesc[pidx].skb = NULL; if (!skb->data_len) memcpy(&d->flit[2], skb->data, skb->len); else skb_copy_bits(skb, 0, &d->flit[2], skb->len); flits = (skb->len + 7) / 8 + 2; cpl->wr.wr_hi = htonl(V_WR_BCNTLFLT(skb->len & 7) | V_WR_OP(FW_WROPCODE_TUNNEL_TX_PKT) | F_WR_SOP | F_WR_EOP | compl); wmb(); cpl->wr.wr_lo = htonl(V_WR_LEN(flits) | V_WR_GEN(gen) | V_WR_TID(q->token)); wr_gen2(d, gen); kfree_skb(skb); return; } flits = 2; } sgp = ndesc == 1 ? (struct sg_ent *)&d->flit[flits] : sgl; sgl_flits = make_sgl(skb, sgp, skb->data, skb_headlen(skb), adap->pdev); if (need_skb_unmap()) ((struct unmap_info *)skb->cb)->len = skb_headlen(skb); write_wr_hdr_sgl(ndesc, skb, d, pidx, q, sgl, flits, sgl_flits, gen, htonl(V_WR_OP(FW_WROPCODE_TUNNEL_TX_PKT) | compl), htonl(V_WR_TID(q->token))); } /** * eth_xmit - add a packet to the Ethernet Tx queue * @skb: the packet * @dev: the egress net device * * Add a packet to an SGE Tx queue. Runs with softirqs disabled. */ int t3_eth_xmit(struct sk_buff *skb, struct net_device *dev) { unsigned int ndesc, pidx, credits, gen, compl; const struct port_info *pi = netdev_priv(dev); struct adapter *adap = dev->priv; struct sge_qset *qs = dev2qset(dev); struct sge_txq *q = &qs->txq[TXQ_ETH]; /* * The chip min packet length is 9 octets but play safe and reject * anything shorter than an Ethernet header. */ if (unlikely(skb->len < ETH_HLEN)) { dev_kfree_skb(skb); return NETDEV_TX_OK; } spin_lock(&q->lock); reclaim_completed_tx(adap, q); credits = q->size - q->in_use; ndesc = calc_tx_descs(skb); if (unlikely(credits < ndesc)) { if (!netif_queue_stopped(dev)) { netif_stop_queue(dev); set_bit(TXQ_ETH, &qs->txq_stopped); q->stops++; dev_err(&adap->pdev->dev, "%s: Tx ring %u full while queue awake!\n", dev->name, q->cntxt_id & 7); } spin_unlock(&q->lock); return NETDEV_TX_BUSY; } q->in_use += ndesc; if (unlikely(credits - ndesc < q->stop_thres)) { q->stops++; netif_stop_queue(dev); set_bit(TXQ_ETH, &qs->txq_stopped); #if !USE_GTS if (should_restart_tx(q) && test_and_clear_bit(TXQ_ETH, &qs->txq_stopped)) { q->restarts++; netif_wake_queue(dev); } #endif } gen = q->gen; q->unacked += ndesc; compl = (q->unacked & 8) << (S_WR_COMPL - 3); q->unacked &= 7; pidx = q->pidx; q->pidx += ndesc; if (q->pidx >= q->size) { q->pidx -= q->size; q->gen ^= 1; } /* update port statistics */ if (skb->ip_summed == CHECKSUM_COMPLETE) qs->port_stats[SGE_PSTAT_TX_CSUM]++; if (skb_shinfo(skb)->gso_size) qs->port_stats[SGE_PSTAT_TSO]++; if (vlan_tx_tag_present(skb) && pi->vlan_grp) qs->port_stats[SGE_PSTAT_VLANINS]++; dev->trans_start = jiffies; spin_unlock(&q->lock); /* * We do not use Tx completion interrupts to free DMAd Tx packets. * This is good for performamce but means that we rely on new Tx * packets arriving to run the destructors of completed packets, * which open up space in their sockets' send queues. Sometimes * we do not get such new packets causing Tx to stall. A single * UDP transmitter is a good example of this situation. We have * a clean up timer that periodically reclaims completed packets * but it doesn't run often enough (nor do we want it to) to prevent * lengthy stalls. A solution to this problem is to run the * destructor early, after the packet is queued but before it's DMAd. * A cons is that we lie to socket memory accounting, but the amount * of extra memory is reasonable (limited by the number of Tx * descriptors), the packets do actually get freed quickly by new * packets almost always, and for protocols like TCP that wait for * acks to really free up the data the extra memory is even less. * On the positive side we run the destructors on the sending CPU * rather than on a potentially different completing CPU, usually a * good thing. We also run them without holding our Tx queue lock, * unlike what reclaim_completed_tx() would otherwise do. * * Run the destructor before telling the DMA engine about the packet * to make sure it doesn't complete and get freed prematurely. */ if (likely(!skb_shared(skb))) skb_orphan(skb); write_tx_pkt_wr(adap, skb, pi, pidx, gen, q, ndesc, compl); check_ring_tx_db(adap, q); return NETDEV_TX_OK; } /** * write_imm - write a packet into a Tx descriptor as immediate data * @d: the Tx descriptor to write * @skb: the packet * @len: the length of packet data to write as immediate data * @gen: the generation bit value to write * * Writes a packet as immediate data into a Tx descriptor. The packet * contains a work request at its beginning. We must write the packet * carefully so the SGE doesn't read accidentally before it's written in * its entirety. */ static inline void write_imm(struct tx_desc *d, struct sk_buff *skb, unsigned int len, unsigned int gen) { struct work_request_hdr *from = (struct work_request_hdr *)skb->data; struct work_request_hdr *to = (struct work_request_hdr *)d; memcpy(&to[1], &from[1], len - sizeof(*from)); to->wr_hi = from->wr_hi | htonl(F_WR_SOP | F_WR_EOP | V_WR_BCNTLFLT(len & 7)); wmb(); to->wr_lo = from->wr_lo | htonl(V_WR_GEN(gen) | V_WR_LEN((len + 7) / 8)); wr_gen2(d, gen); kfree_skb(skb); } /** * check_desc_avail - check descriptor availability on a send queue * @adap: the adapter * @q: the send queue * @skb: the packet needing the descriptors * @ndesc: the number of Tx descriptors needed * @qid: the Tx queue number in its queue set (TXQ_OFLD or TXQ_CTRL) * * Checks if the requested number of Tx descriptors is available on an * SGE send queue. If the queue is already suspended or not enough * descriptors are available the packet is queued for later transmission. * Must be called with the Tx queue locked. * * Returns 0 if enough descriptors are available, 1 if there aren't * enough descriptors and the packet has been queued, and 2 if the caller * needs to retry because there weren't enough descriptors at the * beginning of the call but some freed up in the mean time. */ static inline int check_desc_avail(struct adapter *adap, struct sge_txq *q, struct sk_buff *skb, unsigned int ndesc, unsigned int qid) { if (unlikely(!skb_queue_empty(&q->sendq))) { addq_exit:__skb_queue_tail(&q->sendq, skb); return 1; } if (unlikely(q->size - q->in_use < ndesc)) { struct sge_qset *qs = txq_to_qset(q, qid); set_bit(qid, &qs->txq_stopped); smp_mb__after_clear_bit(); if (should_restart_tx(q) && test_and_clear_bit(qid, &qs->txq_stopped)) return 2; q->stops++; goto addq_exit; } return 0; } /** * reclaim_completed_tx_imm - reclaim completed control-queue Tx descs * @q: the SGE control Tx queue * * This is a variant of reclaim_completed_tx() that is used for Tx queues * that send only immediate data (presently just the control queues) and * thus do not have any sk_buffs to release. */ static inline void reclaim_completed_tx_imm(struct sge_txq *q) { unsigned int reclaim = q->processed - q->cleaned; q->in_use -= reclaim; q->cleaned += reclaim; } static inline int immediate(const struct sk_buff *skb) { return skb->len <= WR_LEN && !skb->data_len; } /** * ctrl_xmit - send a packet through an SGE control Tx queue * @adap: the adapter * @q: the control queue * @skb: the packet * * Send a packet through an SGE control Tx queue. Packets sent through * a control queue must fit entirely as immediate data in a single Tx * descriptor and have no page fragments. */ static int ctrl_xmit(struct adapter *adap, struct sge_txq *q, struct sk_buff *skb) { int ret; struct work_request_hdr *wrp = (struct work_request_hdr *)skb->data; if (unlikely(!immediate(skb))) { WARN_ON(1); dev_kfree_skb(skb); return NET_XMIT_SUCCESS; } wrp->wr_hi |= htonl(F_WR_SOP | F_WR_EOP); wrp->wr_lo = htonl(V_WR_TID(q->token)); spin_lock(&q->lock); again:reclaim_completed_tx_imm(q); ret = check_desc_avail(adap, q, skb, 1, TXQ_CTRL); if (unlikely(ret)) { if (ret == 1) { spin_unlock(&q->lock); return NET_XMIT_CN; } goto again; } write_imm(&q->desc[q->pidx], skb, skb->len, q->gen); q->in_use++; if (++q->pidx >= q->size) { q->pidx = 0; q->gen ^= 1; } spin_unlock(&q->lock); wmb(); t3_write_reg(adap, A_SG_KDOORBELL, F_SELEGRCNTX | V_EGRCNTX(q->cntxt_id)); return NET_XMIT_SUCCESS; } /** * restart_ctrlq - restart a suspended control queue * @qs: the queue set cotaining the control queue * * Resumes transmission on a suspended Tx control queue. */ static void restart_ctrlq(unsigned long data) { struct sk_buff *skb; struct sge_qset *qs = (struct sge_qset *)data; struct sge_txq *q = &qs->txq[TXQ_CTRL]; struct adapter *adap = qs->netdev->priv; spin_lock(&q->lock); again:reclaim_completed_tx_imm(q); while (q->in_use < q->size && (skb = __skb_dequeue(&q->sendq)) != NULL) { write_imm(&q->desc[q->pidx], skb, skb->len, q->gen); if (++q->pidx >= q->size) { q->pidx = 0; q->gen ^= 1; } q->in_use++; } if (!skb_queue_empty(&q->sendq)) { set_bit(TXQ_CTRL, &qs->txq_stopped); smp_mb__after_clear_bit(); if (should_restart_tx(q) && test_and_clear_bit(TXQ_CTRL, &qs->txq_stopped)) goto again; q->stops++; } spin_unlock(&q->lock); t3_write_reg(adap, A_SG_KDOORBELL, F_SELEGRCNTX | V_EGRCNTX(q->cntxt_id)); } /* * Send a management message through control queue 0 */ int t3_mgmt_tx(struct adapter *adap, struct sk_buff *skb) { return ctrl_xmit(adap, &adap->sge.qs[0].txq[TXQ_CTRL], skb); } /** * deferred_unmap_destructor - unmap a packet when it is freed * @skb: the packet * * This is the packet destructor used for Tx packets that need to remain * mapped until they are freed rather than until their Tx descriptors are * freed. */ static void deferred_unmap_destructor(struct sk_buff *skb) { int i; const dma_addr_t *p; const struct skb_shared_info *si; const struct deferred_unmap_info *dui; const struct unmap_info *ui = (struct unmap_info *)skb->cb; dui = (struct deferred_unmap_info *)skb->head; p = dui->addr; if (ui->len) pci_unmap_single(dui->pdev, *p++, ui->len, PCI_DMA_TODEVICE); si = skb_shinfo(skb); for (i = 0; i < si->nr_frags; i++) pci_unmap_page(dui->pdev, *p++, si->frags[i].size, PCI_DMA_TODEVICE); } static void setup_deferred_unmapping(struct sk_buff *skb, struct pci_dev *pdev, const struct sg_ent *sgl, int sgl_flits) { dma_addr_t *p; struct deferred_unmap_info *dui; dui = (struct deferred_unmap_info *)skb->head; dui->pdev = pdev; for (p = dui->addr; sgl_flits >= 3; sgl++, sgl_flits -= 3) { *p++ = be64_to_cpu(sgl->addr[0]); *p++ = be64_to_cpu(sgl->addr[1]); } if (sgl_flits) *p = be64_to_cpu(sgl->addr[0]); } /** * write_ofld_wr - write an offload work request * @adap: the adapter * @skb: the packet to send * @q: the Tx queue * @pidx: index of the first Tx descriptor to write * @gen: the generation value to use * @ndesc: number of descriptors the packet will occupy * * Write an offload work request to send the supplied packet. The packet * data already carry the work request with most fields populated. */ static void write_ofld_wr(struct adapter *adap, struct sk_buff *skb, struct sge_txq *q, unsigned int pidx, unsigned int gen, unsigned int ndesc) { unsigned int sgl_flits, flits; struct work_request_hdr *from; struct sg_ent *sgp, sgl[MAX_SKB_FRAGS / 2 + 1]; struct tx_desc *d = &q->desc[pidx]; if (immediate(skb)) { q->sdesc[pidx].skb = NULL; write_imm(d, skb, skb->len, gen); return; } /* Only TX_DATA builds SGLs */ from = (struct work_request_hdr *)skb->data; memcpy(&d->flit[1], &from[1], skb->h.raw - skb->data - sizeof(*from)); flits = (skb->h.raw - skb->data) / 8; sgp = ndesc == 1 ? (struct sg_ent *)&d->flit[flits] : sgl; sgl_flits = make_sgl(skb, sgp, skb->h.raw, skb->tail - skb->h.raw, adap->pdev); if (need_skb_unmap()) { setup_deferred_unmapping(skb, adap->pdev, sgp, sgl_flits); skb->destructor = deferred_unmap_destructor; ((struct unmap_info *)skb->cb)->len = skb->tail - skb->h.raw; } write_wr_hdr_sgl(ndesc, skb, d, pidx, q, sgl, flits, sgl_flits, gen, from->wr_hi, from->wr_lo); } /** * calc_tx_descs_ofld - calculate # of Tx descriptors for an offload packet * @skb: the packet * * Returns the number of Tx descriptors needed for the given offload * packet. These packets are already fully constructed. */ static inline unsigned int calc_tx_descs_ofld(const struct sk_buff *skb) { unsigned int flits, cnt = skb_shinfo(skb)->nr_frags; if (skb->len <= WR_LEN && cnt == 0) return 1; /* packet fits as immediate data */ flits = (skb->h.raw - skb->data) / 8; /* headers */ if (skb->tail != skb->h.raw) cnt++; return flits_to_desc(flits + sgl_len(cnt)); } /** * ofld_xmit - send a packet through an offload queue * @adap: the adapter * @q: the Tx offload queue * @skb: the packet * * Send an offload packet through an SGE offload queue. */ static int ofld_xmit(struct adapter *adap, struct sge_txq *q, struct sk_buff *skb) { int ret; unsigned int ndesc = calc_tx_descs_ofld(skb), pidx, gen; spin_lock(&q->lock); again:reclaim_completed_tx(adap, q); ret = check_desc_avail(adap, q, skb, ndesc, TXQ_OFLD); if (unlikely(ret)) { if (ret == 1) { skb->priority = ndesc; /* save for restart */ spin_unlock(&q->lock); return NET_XMIT_CN; } goto again; } gen = q->gen; q->in_use += ndesc; pidx = q->pidx; q->pidx += ndesc; if (q->pidx >= q->size) { q->pidx -= q->size; q->gen ^= 1; } spin_unlock(&q->lock); write_ofld_wr(adap, skb, q, pidx, gen, ndesc); check_ring_tx_db(adap, q); return NET_XMIT_SUCCESS; } /** * restart_offloadq - restart a suspended offload queue * @qs: the queue set cotaining the offload queue * * Resumes transmission on a suspended Tx offload queue. */ static void restart_offloadq(unsigned long data) { struct sk_buff *skb; struct sge_qset *qs = (struct sge_qset *)data; struct sge_txq *q = &qs->txq[TXQ_OFLD]; struct adapter *adap = qs->netdev->priv; spin_lock(&q->lock); again:reclaim_completed_tx(adap, q); while ((skb = skb_peek(&q->sendq)) != NULL) { unsigned int gen, pidx; unsigned int ndesc = skb->priority; if (unlikely(q->size - q->in_use < ndesc)) { set_bit(TXQ_OFLD, &qs->txq_stopped); smp_mb__after_clear_bit(); if (should_restart_tx(q) && test_and_clear_bit(TXQ_OFLD, &qs->txq_stopped)) goto again; q->stops++; break; } gen = q->gen; q->in_use += ndesc; pidx = q->pidx; q->pidx += ndesc; if (q->pidx >= q->size) { q->pidx -= q->size; q->gen ^= 1; } __skb_unlink(skb, &q->sendq); spin_unlock(&q->lock); write_ofld_wr(adap, skb, q, pidx, gen, ndesc); spin_lock(&q->lock); } spin_unlock(&q->lock); #if USE_GTS set_bit(TXQ_RUNNING, &q->flags); set_bit(TXQ_LAST_PKT_DB, &q->flags); #endif t3_write_reg(adap, A_SG_KDOORBELL, F_SELEGRCNTX | V_EGRCNTX(q->cntxt_id)); } /** * queue_set - return the queue set a packet should use * @skb: the packet * * Maps a packet to the SGE queue set it should use. The desired queue * set is carried in bits 1-3 in the packet's priority. */ static inline int queue_set(const struct sk_buff *skb) { return skb->priority >> 1; } /** * is_ctrl_pkt - return whether an offload packet is a control packet * @skb: the packet * * Determines whether an offload packet should use an OFLD or a CTRL * Tx queue. This is indicated by bit 0 in the packet's priority. */ static inline int is_ctrl_pkt(const struct sk_buff *skb) { return skb->priority & 1; } /** * t3_offload_tx - send an offload packet * @tdev: the offload device to send to * @skb: the packet * * Sends an offload packet. We use the packet priority to select the * appropriate Tx queue as follows: bit 0 indicates whether the packet * should be sent as regular or control, bits 1-3 select the queue set. */ int t3_offload_tx(struct t3cdev *tdev, struct sk_buff *skb) { struct adapter *adap = tdev2adap(tdev); struct sge_qset *qs = &adap->sge.qs[queue_set(skb)]; if (unlikely(is_ctrl_pkt(skb))) return ctrl_xmit(adap, &qs->txq[TXQ_CTRL], skb); return ofld_xmit(adap, &qs->txq[TXQ_OFLD], skb); } /** * offload_enqueue - add an offload packet to an SGE offload receive queue * @q: the SGE response queue * @skb: the packet * * Add a new offload packet to an SGE response queue's offload packet * queue. If the packet is the first on the queue it schedules the RX * softirq to process the queue. */ static inline void offload_enqueue(struct sge_rspq *q, struct sk_buff *skb) { skb->next = skb->prev = NULL; if (q->rx_tail) q->rx_tail->next = skb; else { struct sge_qset *qs = rspq_to_qset(q); if (__netif_rx_schedule_prep(qs->netdev)) __netif_rx_schedule(qs->netdev); q->rx_head = skb; } q->rx_tail = skb; } /** * deliver_partial_bundle - deliver a (partial) bundle of Rx offload pkts * @tdev: the offload device that will be receiving the packets * @q: the SGE response queue that assembled the bundle * @skbs: the partial bundle * @n: the number of packets in the bundle * * Delivers a (partial) bundle of Rx offload packets to an offload device. */ static inline void deliver_partial_bundle(struct t3cdev *tdev, struct sge_rspq *q, struct sk_buff *skbs[], int n) { if (n) { q->offload_bundles++; tdev->recv(tdev, skbs, n); } } /** * ofld_poll - NAPI handler for offload packets in interrupt mode * @dev: the network device doing the polling * @budget: polling budget * * The NAPI handler for offload packets when a response queue is serviced * by the hard interrupt handler, i.e., when it's operating in non-polling * mode. Creates small packet batches and sends them through the offload * receive handler. Batches need to be of modest size as we do prefetches * on the packets in each. */ static int ofld_poll(struct net_device *dev, int *budget) { struct adapter *adapter = dev->priv; struct sge_qset *qs = dev2qset(dev); struct sge_rspq *q = &qs->rspq; int work_done, limit = min(*budget, dev->quota), avail = limit; while (avail) { struct sk_buff *head, *tail, *skbs[RX_BUNDLE_SIZE]; int ngathered; spin_lock_irq(&q->lock); head = q->rx_head; if (!head) { work_done = limit - avail; *budget -= work_done; dev->quota -= work_done; __netif_rx_complete(dev); spin_unlock_irq(&q->lock); return 0; } tail = q->rx_tail; q->rx_head = q->rx_tail = NULL; spin_unlock_irq(&q->lock); for (ngathered = 0; avail && head; avail--) { prefetch(head->data); skbs[ngathered] = head; head = head->next; skbs[ngathered]->next = NULL; if (++ngathered == RX_BUNDLE_SIZE) { q->offload_bundles++; adapter->tdev.recv(&adapter->tdev, skbs, ngathered); ngathered = 0; } } if (head) { /* splice remaining packets back onto Rx queue */ spin_lock_irq(&q->lock); tail->next = q->rx_head; if (!q->rx_head) q->rx_tail = tail; q->rx_head = head; spin_unlock_irq(&q->lock); } deliver_partial_bundle(&adapter->tdev, q, skbs, ngathered); } work_done = limit - avail; *budget -= work_done; dev->quota -= work_done; return 1; } /** * rx_offload - process a received offload packet * @tdev: the offload device receiving the packet * @rq: the response queue that received the packet * @skb: the packet * @rx_gather: a gather list of packets if we are building a bundle * @gather_idx: index of the next available slot in the bundle * * Process an ingress offload pakcet and add it to the offload ingress * queue. Returns the index of the next available slot in the bundle. */ static inline int rx_offload(struct t3cdev *tdev, struct sge_rspq *rq, struct sk_buff *skb, struct sk_buff *rx_gather[], unsigned int gather_idx) { rq->offload_pkts++; skb->mac.raw = skb->nh.raw = skb->h.raw = skb->data; if (rq->polling) { rx_gather[gather_idx++] = skb; if (gather_idx == RX_BUNDLE_SIZE) { tdev->recv(tdev, rx_gather, RX_BUNDLE_SIZE); gather_idx = 0; rq->offload_bundles++; } } else offload_enqueue(rq, skb); return gather_idx; } /** * restart_tx - check whether to restart suspended Tx queues * @qs: the queue set to resume * * Restarts suspended Tx queues of an SGE queue set if they have enough * free resources to resume operation. */ static void restart_tx(struct sge_qset *qs) { if (test_bit(TXQ_ETH, &qs->txq_stopped) && should_restart_tx(&qs->txq[TXQ_ETH]) && test_and_clear_bit(TXQ_ETH, &qs->txq_stopped)) { qs->txq[TXQ_ETH].restarts++; if (netif_running(qs->netdev)) netif_wake_queue(qs->netdev); } if (test_bit(TXQ_OFLD, &qs->txq_stopped) && should_restart_tx(&qs->txq[TXQ_OFLD]) && test_and_clear_bit(TXQ_OFLD, &qs->txq_stopped)) { qs->txq[TXQ_OFLD].restarts++; tasklet_schedule(&qs->txq[TXQ_OFLD].qresume_tsk); } if (test_bit(TXQ_CTRL, &qs->txq_stopped) && should_restart_tx(&qs->txq[TXQ_CTRL]) && test_and_clear_bit(TXQ_CTRL, &qs->txq_stopped)) { qs->txq[TXQ_CTRL].restarts++; tasklet_schedule(&qs->txq[TXQ_CTRL].qresume_tsk); } } /** * rx_eth - process an ingress ethernet packet * @adap: the adapter * @rq: the response queue that received the packet * @skb: the packet * @pad: amount of padding at the start of the buffer * * Process an ingress ethernet pakcet and deliver it to the stack. * The padding is 2 if the packet was delivered in an Rx buffer and 0 * if it was immediate data in a response. */ static void rx_eth(struct adapter *adap, struct sge_rspq *rq, struct sk_buff *skb, int pad) { struct cpl_rx_pkt *p = (struct cpl_rx_pkt *)(skb->data + pad); struct port_info *pi; skb_pull(skb, sizeof(*p) + pad); skb->dev = adap->port[p->iff]; skb->dev->last_rx = jiffies; skb->protocol = eth_type_trans(skb, skb->dev); pi = netdev_priv(skb->dev); if (pi->rx_csum_offload && p->csum_valid && p->csum == 0xffff && !p->fragment) { rspq_to_qset(rq)->port_stats[SGE_PSTAT_RX_CSUM_GOOD]++; skb->ip_summed = CHECKSUM_UNNECESSARY; } else skb->ip_summed = CHECKSUM_NONE; if (unlikely(p->vlan_valid)) { struct vlan_group *grp = pi->vlan_grp; rspq_to_qset(rq)->port_stats[SGE_PSTAT_VLANEX]++; if (likely(grp)) __vlan_hwaccel_rx(skb, grp, ntohs(p->vlan), rq->polling); else dev_kfree_skb_any(skb); } else if (rq->polling) netif_receive_skb(skb); else netif_rx(skb); } #define SKB_DATA_SIZE 128 static void skb_data_init(struct sk_buff *skb, struct sge_fl_page *p, unsigned int len) { skb->len = len; if (len <= SKB_DATA_SIZE) { memcpy(skb->data, p->va, len); skb->tail += len; put_page(p->frag.page); } else { memcpy(skb->data, p->va, SKB_DATA_SIZE); skb_shinfo(skb)->frags[0].page = p->frag.page; skb_shinfo(skb)->frags[0].page_offset = p->frag.page_offset + SKB_DATA_SIZE; skb_shinfo(skb)->frags[0].size = len - SKB_DATA_SIZE; skb_shinfo(skb)->nr_frags = 1; skb->data_len = len - SKB_DATA_SIZE; skb->tail += SKB_DATA_SIZE; skb->truesize += skb->data_len; } } /** * get_packet - return the next ingress packet buffer from a free list * @adap: the adapter that received the packet * @fl: the SGE free list holding the packet * @len: the packet length including any SGE padding * @drop_thres: # of remaining buffers before we start dropping packets * * Get the next packet from a free list and complete setup of the * sk_buff. If the packet is small we make a copy and recycle the * original buffer, otherwise we use the original buffer itself. If a * positive drop threshold is supplied packets are dropped and their * buffers recycled if (a) the number of remaining buffers is under the * threshold and the packet is too big to copy, or (b) the packet should * be copied but there is no memory for the copy. */ static struct sk_buff *get_packet(struct adapter *adap, struct sge_fl *fl, unsigned int len, unsigned int drop_thres) { struct sk_buff *skb = NULL; struct rx_sw_desc *sd = &fl->sdesc[fl->cidx]; prefetch(sd->t.skb->data); if (len <= SGE_RX_COPY_THRES) { skb = alloc_skb(len, GFP_ATOMIC); if (likely(skb != NULL)) { struct rx_desc *d = &fl->desc[fl->cidx]; dma_addr_t mapping = (dma_addr_t)((u64) be32_to_cpu(d->addr_hi) << 32 | be32_to_cpu(d->addr_lo)); __skb_put(skb, len); pci_dma_sync_single_for_cpu(adap->pdev, mapping, len, PCI_DMA_FROMDEVICE); memcpy(skb->data, sd->t.skb->data, len); pci_dma_sync_single_for_device(adap->pdev, mapping, len, PCI_DMA_FROMDEVICE); } else if (!drop_thres) goto use_orig_buf; recycle: recycle_rx_buf(adap, fl, fl->cidx); return skb; } if (unlikely(fl->credits < drop_thres)) goto recycle; use_orig_buf: pci_unmap_single(adap->pdev, pci_unmap_addr(sd, dma_addr), fl->buf_size, PCI_DMA_FROMDEVICE); skb = sd->t.skb; skb_put(skb, len); __refill_fl(adap, fl); return skb; } /** * handle_rsp_cntrl_info - handles control information in a response * @qs: the queue set corresponding to the response * @flags: the response control flags * * Handles the control information of an SGE response, such as GTS * indications and completion credits for the queue set's Tx queues. * HW coalesces credits, we don't do any extra SW coalescing. */ static inline void handle_rsp_cntrl_info(struct sge_qset *qs, u32 flags) { unsigned int credits; #if USE_GTS if (flags & F_RSPD_TXQ0_GTS) clear_bit(TXQ_RUNNING, &qs->txq[TXQ_ETH].flags); #endif credits = G_RSPD_TXQ0_CR(flags); if (credits) qs->txq[TXQ_ETH].processed += credits; credits = G_RSPD_TXQ2_CR(flags); if (credits) qs->txq[TXQ_CTRL].processed += credits; # if USE_GTS if (flags & F_RSPD_TXQ1_GTS) clear_bit(TXQ_RUNNING, &qs->txq[TXQ_OFLD].flags); # endif credits = G_RSPD_TXQ1_CR(flags); if (credits) qs->txq[TXQ_OFLD].processed += credits; } /** * check_ring_db - check if we need to ring any doorbells * @adapter: the adapter * @qs: the queue set whose Tx queues are to be examined * @sleeping: indicates which Tx queue sent GTS * * Checks if some of a queue set's Tx queues need to ring their doorbells * to resume transmission after idling while they still have unprocessed * descriptors. */ static void check_ring_db(struct adapter *adap, struct sge_qset *qs, unsigned int sleeping) { if (sleeping & F_RSPD_TXQ0_GTS) { struct sge_txq *txq = &qs->txq[TXQ_ETH]; if (txq->cleaned + txq->in_use != txq->processed && !test_and_set_bit(TXQ_LAST_PKT_DB, &txq->flags)) { set_bit(TXQ_RUNNING, &txq->flags); t3_write_reg(adap, A_SG_KDOORBELL, F_SELEGRCNTX | V_EGRCNTX(txq->cntxt_id)); } } if (sleeping & F_RSPD_TXQ1_GTS) { struct sge_txq *txq = &qs->txq[TXQ_OFLD]; if (txq->cleaned + txq->in_use != txq->processed && !test_and_set_bit(TXQ_LAST_PKT_DB, &txq->flags)) { set_bit(TXQ_RUNNING, &txq->flags); t3_write_reg(adap, A_SG_KDOORBELL, F_SELEGRCNTX | V_EGRCNTX(txq->cntxt_id)); } } } /** * is_new_response - check if a response is newly written * @r: the response descriptor * @q: the response queue * * Returns true if a response descriptor contains a yet unprocessed * response. */ static inline int is_new_response(const struct rsp_desc *r, const struct sge_rspq *q) { return (r->intr_gen & F_RSPD_GEN2) == q->gen; } #define RSPD_GTS_MASK (F_RSPD_TXQ0_GTS | F_RSPD_TXQ1_GTS) #define RSPD_CTRL_MASK (RSPD_GTS_MASK | \ V_RSPD_TXQ0_CR(M_RSPD_TXQ0_CR) | \ V_RSPD_TXQ1_CR(M_RSPD_TXQ1_CR) | \ V_RSPD_TXQ2_CR(M_RSPD_TXQ2_CR)) /* How long to delay the next interrupt in case of memory shortage, in 0.1us. */ #define NOMEM_INTR_DELAY 2500 /** * process_responses - process responses from an SGE response queue * @adap: the adapter * @qs: the queue set to which the response queue belongs * @budget: how many responses can be processed in this round * * Process responses from an SGE response queue up to the supplied budget. * Responses include received packets as well as credits and other events * for the queues that belong to the response queue's queue set. * A negative budget is effectively unlimited. * * Additionally choose the interrupt holdoff time for the next interrupt * on this queue. If the system is under memory shortage use a fairly * long delay to help recovery. */ static int process_responses(struct adapter *adap, struct sge_qset *qs, int budget) { struct sge_rspq *q = &qs->rspq; struct rsp_desc *r = &q->desc[q->cidx]; int budget_left = budget; unsigned int sleeping = 0; struct sk_buff *offload_skbs[RX_BUNDLE_SIZE]; int ngathered = 0; q->next_holdoff = q->holdoff_tmr; while (likely(budget_left && is_new_response(r, q))) { int eth, ethpad = 2; struct sk_buff *skb = NULL; u32 len, flags = ntohl(r->flags); u32 rss_hi = *(const u32 *)r, rss_lo = r->rss_hdr.rss_hash_val; eth = r->rss_hdr.opcode == CPL_RX_PKT; if (unlikely(flags & F_RSPD_ASYNC_NOTIF)) { skb = alloc_skb(AN_PKT_SIZE, GFP_ATOMIC); if (!skb) goto no_mem; memcpy(__skb_put(skb, AN_PKT_SIZE), r, AN_PKT_SIZE); skb->data[0] = CPL_ASYNC_NOTIF; rss_hi = htonl(CPL_ASYNC_NOTIF << 24); q->async_notif++; } else if (flags & F_RSPD_IMM_DATA_VALID) { skb = get_imm_packet(r); if (unlikely(!skb)) { no_mem: q->next_holdoff = NOMEM_INTR_DELAY; q->nomem++; /* consume one credit since we tried */ budget_left--; break; } q->imm_data++; ethpad = 0; } else if ((len = ntohl(r->len_cq)) != 0) { struct sge_fl *fl = (len & F_RSPD_FLQ) ? &qs->fl[1] : &qs->fl[0]; if (fl->buf_size == RX_PAGE_SIZE) { struct rx_sw_desc *sd = &fl->sdesc[fl->cidx]; struct sge_fl_page *p = &sd->t.page; prefetch(p->va); prefetch(p->va + L1_CACHE_BYTES); __refill_fl(adap, fl); pci_unmap_single(adap->pdev, pci_unmap_addr(sd, dma_addr), fl->buf_size, PCI_DMA_FROMDEVICE); if (eth) { if (unlikely(fl->credits < SGE_RX_DROP_THRES)) goto eth_recycle; skb = alloc_skb(SKB_DATA_SIZE, GFP_ATOMIC); if (unlikely(!skb)) { eth_recycle: q->rx_drops++; recycle_rx_buf(adap, fl, fl->cidx); goto eth_done; } } else { skb = alloc_skb(SKB_DATA_SIZE, GFP_ATOMIC); if (unlikely(!skb)) goto no_mem; } skb_data_init(skb, p, G_RSPD_LEN(len)); eth_done: fl->credits--; q->eth_pkts++; } else { fl->credits--; skb = get_packet(adap, fl, G_RSPD_LEN(len), eth ? SGE_RX_DROP_THRES : 0); } if (++fl->cidx == fl->size) fl->cidx = 0; } else q->pure_rsps++; if (flags & RSPD_CTRL_MASK) { sleeping |= flags & RSPD_GTS_MASK; handle_rsp_cntrl_info(qs, flags); } r++; if (unlikely(++q->cidx == q->size)) { q->cidx = 0; q->gen ^= 1; r = q->desc; } prefetch(r); if (++q->credits >= (q->size / 4)) { refill_rspq(adap, q, q->credits); q->credits = 0; } if (skb) { /* Preserve the RSS info in csum & priority */ skb->csum = rss_hi; skb->priority = rss_lo; if (eth) rx_eth(adap, q, skb, ethpad); else { if (unlikely(r->rss_hdr.opcode == CPL_TRACE_PKT)) __skb_pull(skb, ethpad); ngathered = rx_offload(&adap->tdev, q, skb, offload_skbs, ngathered); } } --budget_left; } deliver_partial_bundle(&adap->tdev, q, offload_skbs, ngathered); if (sleeping) check_ring_db(adap, qs, sleeping); smp_mb(); /* commit Tx queue .processed updates */ if (unlikely(qs->txq_stopped != 0)) restart_tx(qs); budget -= budget_left; return budget; } static inline int is_pure_response(const struct rsp_desc *r) { u32 n = ntohl(r->flags) & (F_RSPD_ASYNC_NOTIF | F_RSPD_IMM_DATA_VALID); return (n | r->len_cq) == 0; } /** * napi_rx_handler - the NAPI handler for Rx processing * @dev: the net device * @budget: how many packets we can process in this round * * Handler for new data events when using NAPI. */ static int napi_rx_handler(struct net_device *dev, int *budget) { struct adapter *adap = dev->priv; struct sge_qset *qs = dev2qset(dev); int effective_budget = min(*budget, dev->quota); int work_done = process_responses(adap, qs, effective_budget); *budget -= work_done; dev->quota -= work_done; if (work_done >= effective_budget) return 1; netif_rx_complete(dev); /* * Because we don't atomically flush the following write it is * possible that in very rare cases it can reach the device in a way * that races with a new response being written plus an error interrupt * causing the NAPI interrupt handler below to return unhandled status * to the OS. To protect against this would require flushing the write * and doing both the write and the flush with interrupts off. Way too * expensive and unjustifiable given the rarity of the race. * * The race cannot happen at all with MSI-X. */ t3_write_reg(adap, A_SG_GTS, V_RSPQ(qs->rspq.cntxt_id) | V_NEWTIMER(qs->rspq.next_holdoff) | V_NEWINDEX(qs->rspq.cidx)); return 0; } /* * Returns true if the device is already scheduled for polling. */ static inline int napi_is_scheduled(struct net_device *dev) { return test_bit(__LINK_STATE_RX_SCHED, &dev->state); } /** * process_pure_responses - process pure responses from a response queue * @adap: the adapter * @qs: the queue set owning the response queue * @r: the first pure response to process * * A simpler version of process_responses() that handles only pure (i.e., * non data-carrying) responses. Such respones are too light-weight to * justify calling a softirq under NAPI, so we handle them specially in * the interrupt handler. The function is called with a pointer to a * response, which the caller must ensure is a valid pure response. * * Returns 1 if it encounters a valid data-carrying response, 0 otherwise. */ static int process_pure_responses(struct adapter *adap, struct sge_qset *qs, struct rsp_desc *r) { struct sge_rspq *q = &qs->rspq; unsigned int sleeping = 0; do { u32 flags = ntohl(r->flags); r++; if (unlikely(++q->cidx == q->size)) { q->cidx = 0; q->gen ^= 1; r = q->desc; } prefetch(r); if (flags & RSPD_CTRL_MASK) { sleeping |= flags & RSPD_GTS_MASK; handle_rsp_cntrl_info(qs, flags); } q->pure_rsps++; if (++q->credits >= (q->size / 4)) { refill_rspq(adap, q, q->credits); q->credits = 0; } } while (is_new_response(r, q) && is_pure_response(r)); if (sleeping) check_ring_db(adap, qs, sleeping); smp_mb(); /* commit Tx queue .processed updates */ if (unlikely(qs->txq_stopped != 0)) restart_tx(qs); return is_new_response(r, q); } /** * handle_responses - decide what to do with new responses in NAPI mode * @adap: the adapter * @q: the response queue * * This is used by the NAPI interrupt handlers to decide what to do with * new SGE responses. If there are no new responses it returns -1. If * there are new responses and they are pure (i.e., non-data carrying) * it handles them straight in hard interrupt context as they are very * cheap and don't deliver any packets. Finally, if there are any data * signaling responses it schedules the NAPI handler. Returns 1 if it * schedules NAPI, 0 if all new responses were pure. * * The caller must ascertain NAPI is not already running. */ static inline int handle_responses(struct adapter *adap, struct sge_rspq *q) { struct sge_qset *qs = rspq_to_qset(q); struct rsp_desc *r = &q->desc[q->cidx]; if (!is_new_response(r, q)) return -1; if (is_pure_response(r) && process_pure_responses(adap, qs, r) == 0) { t3_write_reg(adap, A_SG_GTS, V_RSPQ(q->cntxt_id) | V_NEWTIMER(q->holdoff_tmr) | V_NEWINDEX(q->cidx)); return 0; } if (likely(__netif_rx_schedule_prep(qs->netdev))) __netif_rx_schedule(qs->netdev); return 1; } /* * The MSI-X interrupt handler for an SGE response queue for the non-NAPI case * (i.e., response queue serviced in hard interrupt). */ irqreturn_t t3_sge_intr_msix(int irq, void *cookie) { struct sge_qset *qs = cookie; struct adapter *adap = qs->netdev->priv; struct sge_rspq *q = &qs->rspq; spin_lock(&q->lock); if (process_responses(adap, qs, -1) == 0) q->unhandled_irqs++; t3_write_reg(adap, A_SG_GTS, V_RSPQ(q->cntxt_id) | V_NEWTIMER(q->next_holdoff) | V_NEWINDEX(q->cidx)); spin_unlock(&q->lock); return IRQ_HANDLED; } /* * The MSI-X interrupt handler for an SGE response queue for the NAPI case * (i.e., response queue serviced by NAPI polling). */ irqreturn_t t3_sge_intr_msix_napi(int irq, void *cookie) { struct sge_qset *qs = cookie; struct adapter *adap = qs->netdev->priv; struct sge_rspq *q = &qs->rspq; spin_lock(&q->lock); BUG_ON(napi_is_scheduled(qs->netdev)); if (handle_responses(adap, q) < 0) q->unhandled_irqs++; spin_unlock(&q->lock); return IRQ_HANDLED; } /* * The non-NAPI MSI interrupt handler. This needs to handle data events from * SGE response queues as well as error and other async events as they all use * the same MSI vector. We use one SGE response queue per port in this mode * and protect all response queues with queue 0's lock. */ static irqreturn_t t3_intr_msi(int irq, void *cookie) { int new_packets = 0; struct adapter *adap = cookie; struct sge_rspq *q = &adap->sge.qs[0].rspq; spin_lock(&q->lock); if (process_responses(adap, &adap->sge.qs[0], -1)) { t3_write_reg(adap, A_SG_GTS, V_RSPQ(q->cntxt_id) | V_NEWTIMER(q->next_holdoff) | V_NEWINDEX(q->cidx)); new_packets = 1; } if (adap->params.nports == 2 && process_responses(adap, &adap->sge.qs[1], -1)) { struct sge_rspq *q1 = &adap->sge.qs[1].rspq; t3_write_reg(adap, A_SG_GTS, V_RSPQ(q1->cntxt_id) | V_NEWTIMER(q1->next_holdoff) | V_NEWINDEX(q1->cidx)); new_packets = 1; } if (!new_packets && t3_slow_intr_handler(adap) == 0) q->unhandled_irqs++; spin_unlock(&q->lock); return IRQ_HANDLED; } static int rspq_check_napi(struct net_device *dev, struct sge_rspq *q) { if (!napi_is_scheduled(dev) && is_new_response(&q->desc[q->cidx], q)) { if (likely(__netif_rx_schedule_prep(dev))) __netif_rx_schedule(dev); return 1; } return 0; } /* * The MSI interrupt handler for the NAPI case (i.e., response queues serviced * by NAPI polling). Handles data events from SGE response queues as well as * error and other async events as they all use the same MSI vector. We use * one SGE response queue per port in this mode and protect all response * queues with queue 0's lock. */ irqreturn_t t3_intr_msi_napi(int irq, void *cookie) { int new_packets; struct adapter *adap = cookie; struct sge_rspq *q = &adap->sge.qs[0].rspq; spin_lock(&q->lock); new_packets = rspq_check_napi(adap->sge.qs[0].netdev, q); if (adap->params.nports == 2) new_packets += rspq_check_napi(adap->sge.qs[1].netdev, &adap->sge.qs[1].rspq); if (!new_packets && t3_slow_intr_handler(adap) == 0) q->unhandled_irqs++; spin_unlock(&q->lock); return IRQ_HANDLED; } /* * A helper function that processes responses and issues GTS. */ static inline int process_responses_gts(struct adapter *adap, struct sge_rspq *rq) { int work; work = process_responses(adap, rspq_to_qset(rq), -1); t3_write_reg(adap, A_SG_GTS, V_RSPQ(rq->cntxt_id) | V_NEWTIMER(rq->next_holdoff) | V_NEWINDEX(rq->cidx)); return work; } /* * The legacy INTx interrupt handler. This needs to handle data events from * SGE response queues as well as error and other async events as they all use * the same interrupt pin. We use one SGE response queue per port in this mode * and protect all response queues with queue 0's lock. */ static irqreturn_t t3_intr(int irq, void *cookie) { int work_done, w0, w1; struct adapter *adap = cookie; struct sge_rspq *q0 = &adap->sge.qs[0].rspq; struct sge_rspq *q1 = &adap->sge.qs[1].rspq; spin_lock(&q0->lock); w0 = is_new_response(&q0->desc[q0->cidx], q0); w1 = adap->params.nports == 2 && is_new_response(&q1->desc[q1->cidx], q1); if (likely(w0 | w1)) { t3_write_reg(adap, A_PL_CLI, 0); t3_read_reg(adap, A_PL_CLI); /* flush */ if (likely(w0)) process_responses_gts(adap, q0); if (w1) process_responses_gts(adap, q1); work_done = w0 | w1; } else work_done = t3_slow_intr_handler(adap); spin_unlock(&q0->lock); return IRQ_RETVAL(work_done != 0); } /* * Interrupt handler for legacy INTx interrupts for T3B-based cards. * Handles data events from SGE response queues as well as error and other * async events as they all use the same interrupt pin. We use one SGE * response queue per port in this mode and protect all response queues with * queue 0's lock. */ static irqreturn_t t3b_intr(int irq, void *cookie) { u32 map; struct adapter *adap = cookie; struct sge_rspq *q0 = &adap->sge.qs[0].rspq; t3_write_reg(adap, A_PL_CLI, 0); map = t3_read_reg(adap, A_SG_DATA_INTR); if (unlikely(!map)) /* shared interrupt, most likely */ return IRQ_NONE; spin_lock(&q0->lock); if (unlikely(map & F_ERRINTR)) t3_slow_intr_handler(adap); if (likely(map & 1)) process_responses_gts(adap, q0); if (map & 2) process_responses_gts(adap, &adap->sge.qs[1].rspq); spin_unlock(&q0->lock); return IRQ_HANDLED; } /* * NAPI interrupt handler for legacy INTx interrupts for T3B-based cards. * Handles data events from SGE response queues as well as error and other * async events as they all use the same interrupt pin. We use one SGE * response queue per port in this mode and protect all response queues with * queue 0's lock. */ static irqreturn_t t3b_intr_napi(int irq, void *cookie) { u32 map; struct net_device *dev; struct adapter *adap = cookie; struct sge_rspq *q0 = &adap->sge.qs[0].rspq; t3_write_reg(adap, A_PL_CLI, 0); map = t3_read_reg(adap, A_SG_DATA_INTR); if (unlikely(!map)) /* shared interrupt, most likely */ return IRQ_NONE; spin_lock(&q0->lock); if (unlikely(map & F_ERRINTR)) t3_slow_intr_handler(adap); if (likely(map & 1)) { dev = adap->sge.qs[0].netdev; if (likely(__netif_rx_schedule_prep(dev))) __netif_rx_schedule(dev); } if (map & 2) { dev = adap->sge.qs[1].netdev; if (likely(__netif_rx_schedule_prep(dev))) __netif_rx_schedule(dev); } spin_unlock(&q0->lock); return IRQ_HANDLED; } /** * t3_intr_handler - select the top-level interrupt handler * @adap: the adapter * @polling: whether using NAPI to service response queues * * Selects the top-level interrupt handler based on the type of interrupts * (MSI-X, MSI, or legacy) and whether NAPI will be used to service the * response queues. */ intr_handler_t t3_intr_handler(struct adapter *adap, int polling) { if (adap->flags & USING_MSIX) return polling ? t3_sge_intr_msix_napi : t3_sge_intr_msix; if (adap->flags & USING_MSI) return polling ? t3_intr_msi_napi : t3_intr_msi; if (adap->params.rev > 0) return polling ? t3b_intr_napi : t3b_intr; return t3_intr; } /** * t3_sge_err_intr_handler - SGE async event interrupt handler * @adapter: the adapter * * Interrupt handler for SGE asynchronous (non-data) events. */ void t3_sge_err_intr_handler(struct adapter *adapter) { unsigned int v, status = t3_read_reg(adapter, A_SG_INT_CAUSE); if (status & F_RSPQCREDITOVERFOW) CH_ALERT(adapter, "SGE response queue credit overflow\n"); if (status & F_RSPQDISABLED) { v = t3_read_reg(adapter, A_SG_RSPQ_FL_STATUS); CH_ALERT(adapter, "packet delivered to disabled response queue " "(0x%x)\n", (v >> S_RSPQ0DISABLED) & 0xff); } t3_write_reg(adapter, A_SG_INT_CAUSE, status); if (status & (F_RSPQCREDITOVERFOW | F_RSPQDISABLED)) t3_fatal_err(adapter); } /** * sge_timer_cb - perform periodic maintenance of an SGE qset * @data: the SGE queue set to maintain * * Runs periodically from a timer to perform maintenance of an SGE queue * set. It performs two tasks: * * a) Cleans up any completed Tx descriptors that may still be pending. * Normal descriptor cleanup happens when new packets are added to a Tx * queue so this timer is relatively infrequent and does any cleanup only * if the Tx queue has not seen any new packets in a while. We make a * best effort attempt to reclaim descriptors, in that we don't wait * around if we cannot get a queue's lock (which most likely is because * someone else is queueing new packets and so will also handle the clean * up). Since control queues use immediate data exclusively we don't * bother cleaning them up here. * * b) Replenishes Rx queues that have run out due to memory shortage. * Normally new Rx buffers are added when existing ones are consumed but * when out of memory a queue can become empty. We try to add only a few * buffers here, the queue will be replenished fully as these new buffers * are used up if memory shortage has subsided. */ static void sge_timer_cb(unsigned long data) { spinlock_t *lock; struct sge_qset *qs = (struct sge_qset *)data; struct adapter *adap = qs->netdev->priv; if (spin_trylock(&qs->txq[TXQ_ETH].lock)) { reclaim_completed_tx(adap, &qs->txq[TXQ_ETH]); spin_unlock(&qs->txq[TXQ_ETH].lock); } if (spin_trylock(&qs->txq[TXQ_OFLD].lock)) { reclaim_completed_tx(adap, &qs->txq[TXQ_OFLD]); spin_unlock(&qs->txq[TXQ_OFLD].lock); } lock = (adap->flags & USING_MSIX) ? &qs->rspq.lock : &adap->sge.qs[0].rspq.lock; if (spin_trylock_irq(lock)) { if (!napi_is_scheduled(qs->netdev)) { u32 status = t3_read_reg(adap, A_SG_RSPQ_FL_STATUS); if (qs->fl[0].credits < qs->fl[0].size) __refill_fl(adap, &qs->fl[0]); if (qs->fl[1].credits < qs->fl[1].size) __refill_fl(adap, &qs->fl[1]); if (status & (1 << qs->rspq.cntxt_id)) { qs->rspq.starved++; if (qs->rspq.credits) { refill_rspq(adap, &qs->rspq, 1); qs->rspq.credits--; qs->rspq.restarted++; t3_write_reg(adap, A_SG_RSPQ_FL_STATUS, 1 << qs->rspq.cntxt_id); } } } spin_unlock_irq(lock); } mod_timer(&qs->tx_reclaim_timer, jiffies + TX_RECLAIM_PERIOD); } /** * t3_update_qset_coalesce - update coalescing settings for a queue set * @qs: the SGE queue set * @p: new queue set parameters * * Update the coalescing settings for an SGE queue set. Nothing is done * if the queue set is not initialized yet. */ void t3_update_qset_coalesce(struct sge_qset *qs, const struct qset_params *p) { if (!qs->netdev) return; qs->rspq.holdoff_tmr = max(p->coalesce_usecs * 10, 1U);/* can't be 0 */ qs->rspq.polling = p->polling; qs->netdev->poll = p->polling ? napi_rx_handler : ofld_poll; } /** * t3_sge_alloc_qset - initialize an SGE queue set * @adapter: the adapter * @id: the queue set id * @nports: how many Ethernet ports will be using this queue set * @irq_vec_idx: the IRQ vector index for response queue interrupts * @p: configuration parameters for this queue set * @ntxq: number of Tx queues for the queue set * @netdev: net device associated with this queue set * * Allocate resources and initialize an SGE queue set. A queue set * comprises a response queue, two Rx free-buffer queues, and up to 3 * Tx queues. The Tx queues are assigned roles in the order Ethernet * queue, offload queue, and control queue. */ int t3_sge_alloc_qset(struct adapter *adapter, unsigned int id, int nports, int irq_vec_idx, const struct qset_params *p, int ntxq, struct net_device *netdev) { int i, ret = -ENOMEM; struct sge_qset *q = &adapter->sge.qs[id]; init_qset_cntxt(q, id); init_timer(&q->tx_reclaim_timer); q->tx_reclaim_timer.data = (unsigned long)q; q->tx_reclaim_timer.function = sge_timer_cb; q->fl[0].desc = alloc_ring(adapter->pdev, p->fl_size, sizeof(struct rx_desc), sizeof(struct rx_sw_desc), &q->fl[0].phys_addr, &q->fl[0].sdesc); if (!q->fl[0].desc) goto err; q->fl[1].desc = alloc_ring(adapter->pdev, p->jumbo_size, sizeof(struct rx_desc), sizeof(struct rx_sw_desc), &q->fl[1].phys_addr, &q->fl[1].sdesc); if (!q->fl[1].desc) goto err; q->rspq.desc = alloc_ring(adapter->pdev, p->rspq_size, sizeof(struct rsp_desc), 0, &q->rspq.phys_addr, NULL); if (!q->rspq.desc) goto err; for (i = 0; i < ntxq; ++i) { /* * The control queue always uses immediate data so does not * need to keep track of any sk_buffs. */ size_t sz = i == TXQ_CTRL ? 0 : sizeof(struct tx_sw_desc); q->txq[i].desc = alloc_ring(adapter->pdev, p->txq_size[i], sizeof(struct tx_desc), sz, &q->txq[i].phys_addr, &q->txq[i].sdesc); if (!q->txq[i].desc) goto err; q->txq[i].gen = 1; q->txq[i].size = p->txq_size[i]; spin_lock_init(&q->txq[i].lock); skb_queue_head_init(&q->txq[i].sendq); } tasklet_init(&q->txq[TXQ_OFLD].qresume_tsk, restart_offloadq, (unsigned long)q); tasklet_init(&q->txq[TXQ_CTRL].qresume_tsk, restart_ctrlq, (unsigned long)q); q->fl[0].gen = q->fl[1].gen = 1; q->fl[0].size = p->fl_size; q->fl[1].size = p->jumbo_size; q->rspq.gen = 1; q->rspq.size = p->rspq_size; spin_lock_init(&q->rspq.lock); q->txq[TXQ_ETH].stop_thres = nports * flits_to_desc(sgl_len(MAX_SKB_FRAGS + 1) + 3); if (ntxq == 1) { #ifdef USE_RX_PAGE q->fl[0].buf_size = RX_PAGE_SIZE; #else q->fl[0].buf_size = SGE_RX_SM_BUF_SIZE + 2 + sizeof(struct cpl_rx_pkt); #endif q->fl[1].buf_size = MAX_FRAME_SIZE + 2 + sizeof(struct cpl_rx_pkt); } else { #ifdef USE_RX_PAGE q->fl[0].buf_size = RX_PAGE_SIZE; #else q->fl[0].buf_size = SGE_RX_SM_BUF_SIZE + sizeof(struct cpl_rx_data); #endif q->fl[1].buf_size = (16 * 1024) - SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); } spin_lock(&adapter->sge.reg_lock); /* FL threshold comparison uses < */ ret = t3_sge_init_rspcntxt(adapter, q->rspq.cntxt_id, irq_vec_idx, q->rspq.phys_addr, q->rspq.size, q->fl[0].buf_size, 1, 0); if (ret) goto err_unlock; for (i = 0; i < SGE_RXQ_PER_SET; ++i) { ret = t3_sge_init_flcntxt(adapter, q->fl[i].cntxt_id, 0, q->fl[i].phys_addr, q->fl[i].size, q->fl[i].buf_size, p->cong_thres, 1, 0); if (ret) goto err_unlock; } ret = t3_sge_init_ecntxt(adapter, q->txq[TXQ_ETH].cntxt_id, USE_GTS, SGE_CNTXT_ETH, id, q->txq[TXQ_ETH].phys_addr, q->txq[TXQ_ETH].size, q->txq[TXQ_ETH].token, 1, 0); if (ret) goto err_unlock; if (ntxq > 1) { ret = t3_sge_init_ecntxt(adapter, q->txq[TXQ_OFLD].cntxt_id, USE_GTS, SGE_CNTXT_OFLD, id, q->txq[TXQ_OFLD].phys_addr, q->txq[TXQ_OFLD].size, 0, 1, 0); if (ret) goto err_unlock; } if (ntxq > 2) { ret = t3_sge_init_ecntxt(adapter, q->txq[TXQ_CTRL].cntxt_id, 0, SGE_CNTXT_CTRL, id, q->txq[TXQ_CTRL].phys_addr, q->txq[TXQ_CTRL].size, q->txq[TXQ_CTRL].token, 1, 0); if (ret) goto err_unlock; } spin_unlock(&adapter->sge.reg_lock); q->netdev = netdev; t3_update_qset_coalesce(q, p); /* * We use atalk_ptr as a backpointer to a qset. In case a device is * associated with multiple queue sets only the first one sets * atalk_ptr. */ if (netdev->atalk_ptr == NULL) netdev->atalk_ptr = q; refill_fl(adapter, &q->fl[0], q->fl[0].size, GFP_KERNEL); refill_fl(adapter, &q->fl[1], q->fl[1].size, GFP_KERNEL); refill_rspq(adapter, &q->rspq, q->rspq.size - 1); t3_write_reg(adapter, A_SG_GTS, V_RSPQ(q->rspq.cntxt_id) | V_NEWTIMER(q->rspq.holdoff_tmr)); mod_timer(&q->tx_reclaim_timer, jiffies + TX_RECLAIM_PERIOD); return 0; err_unlock: spin_unlock(&adapter->sge.reg_lock); err: t3_free_qset(adapter, q); return ret; } /** * t3_free_sge_resources - free SGE resources * @adap: the adapter * * Frees resources used by the SGE queue sets. */ void t3_free_sge_resources(struct adapter *adap) { int i; for (i = 0; i < SGE_QSETS; ++i) t3_free_qset(adap, &adap->sge.qs[i]); } /** * t3_sge_start - enable SGE * @adap: the adapter * * Enables the SGE for DMAs. This is the last step in starting packet * transfers. */ void t3_sge_start(struct adapter *adap) { t3_set_reg_field(adap, A_SG_CONTROL, F_GLOBALENABLE, F_GLOBALENABLE); } /** * t3_sge_stop - disable SGE operation * @adap: the adapter * * Disables the DMA engine. This can be called in emeregencies (e.g., * from error interrupts) or from normal process context. In the latter * case it also disables any pending queue restart tasklets. Note that * if it is called in interrupt context it cannot disable the restart * tasklets as it cannot wait, however the tasklets will have no effect * since the doorbells are disabled and the driver will call this again * later from process context, at which time the tasklets will be stopped * if they are still running. */ void t3_sge_stop(struct adapter *adap) { t3_set_reg_field(adap, A_SG_CONTROL, F_GLOBALENABLE, 0); if (!in_interrupt()) { int i; for (i = 0; i < SGE_QSETS; ++i) { struct sge_qset *qs = &adap->sge.qs[i]; tasklet_kill(&qs->txq[TXQ_OFLD].qresume_tsk); tasklet_kill(&qs->txq[TXQ_CTRL].qresume_tsk); } } } /** * t3_sge_init - initialize SGE * @adap: the adapter * @p: the SGE parameters * * Performs SGE initialization needed every time after a chip reset. * We do not initialize any of the queue sets here, instead the driver * top-level must request those individually. We also do not enable DMA * here, that should be done after the queues have been set up. */ void t3_sge_init(struct adapter *adap, struct sge_params *p) { unsigned int ctrl, ups = ffs(pci_resource_len(adap->pdev, 2) >> 12); ctrl = F_DROPPKT | V_PKTSHIFT(2) | F_FLMODE | F_AVOIDCQOVFL | F_CQCRDTCTRL | V_HOSTPAGESIZE(PAGE_SHIFT - 11) | F_BIGENDIANINGRESS | V_USERSPACESIZE(ups ? ups - 1 : 0) | F_ISCSICOALESCING; #if SGE_NUM_GENBITS == 1 ctrl |= F_EGRGENCTRL; #endif if (adap->params.rev > 0) { if (!(adap->flags & (USING_MSIX | USING_MSI))) ctrl |= F_ONEINTMULTQ | F_OPTONEINTMULTQ; ctrl |= F_CQCRDTCTRL | F_AVOIDCQOVFL; } t3_write_reg(adap, A_SG_CONTROL, ctrl); t3_write_reg(adap, A_SG_EGR_RCQ_DRB_THRSH, V_HIRCQDRBTHRSH(512) | V_LORCQDRBTHRSH(512)); t3_write_reg(adap, A_SG_TIMER_TICK, core_ticks_per_usec(adap) / 10); t3_write_reg(adap, A_SG_CMDQ_CREDIT_TH, V_THRESHOLD(32) | V_TIMEOUT(200 * core_ticks_per_usec(adap))); t3_write_reg(adap, A_SG_HI_DRB_HI_THRSH, 1000); t3_write_reg(adap, A_SG_HI_DRB_LO_THRSH, 256); t3_write_reg(adap, A_SG_LO_DRB_HI_THRSH, 1000); t3_write_reg(adap, A_SG_LO_DRB_LO_THRSH, 256); t3_write_reg(adap, A_SG_OCO_BASE, V_BASE1(0xfff)); t3_write_reg(adap, A_SG_DRB_PRI_THRESH, 63 * 1024); } /** * t3_sge_prep - one-time SGE initialization * @adap: the associated adapter * @p: SGE parameters * * Performs one-time initialization of SGE SW state. Includes determining * defaults for the assorted SGE parameters, which admins can change until * they are used to initialize the SGE. */ void __devinit t3_sge_prep(struct adapter *adap, struct sge_params *p) { int i; p->max_pkt_size = (16 * 1024) - sizeof(struct cpl_rx_data) - SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); for (i = 0; i < SGE_QSETS; ++i) { struct qset_params *q = p->qset + i; q->polling = adap->params.rev > 0; q->coalesce_usecs = 5; q->rspq_size = 1024; q->fl_size = 1024; q->jumbo_size = 512; q->txq_size[TXQ_ETH] = 1024; q->txq_size[TXQ_OFLD] = 1024; q->txq_size[TXQ_CTRL] = 256; q->cong_thres = 0; } spin_lock_init(&adap->sge.reg_lock); } /** * t3_get_desc - dump an SGE descriptor for debugging purposes * @qs: the queue set * @qnum: identifies the specific queue (0..2: Tx, 3:response, 4..5: Rx) * @idx: the descriptor index in the queue * @data: where to dump the descriptor contents * * Dumps the contents of a HW descriptor of an SGE queue. Returns the * size of the descriptor. */ int t3_get_desc(const struct sge_qset *qs, unsigned int qnum, unsigned int idx, unsigned char *data) { if (qnum >= 6) return -EINVAL; if (qnum < 3) { if (!qs->txq[qnum].desc || idx >= qs->txq[qnum].size) return -EINVAL; memcpy(data, &qs->txq[qnum].desc[idx], sizeof(struct tx_desc)); return sizeof(struct tx_desc); } if (qnum == 3) { if (!qs->rspq.desc || idx >= qs->rspq.size) return -EINVAL; memcpy(data, &qs->rspq.desc[idx], sizeof(struct rsp_desc)); return sizeof(struct rsp_desc); } qnum -= 4; if (!qs->fl[qnum].desc || idx >= qs->fl[qnum].size) return -EINVAL; memcpy(data, &qs->fl[qnum].desc[idx], sizeof(struct rx_desc)); return sizeof(struct rx_desc); }