diff options
Diffstat (limited to 'drivers/dma/iop-adma.c')
-rw-r--r-- | drivers/dma/iop-adma.c | 1467 |
1 files changed, 1467 insertions, 0 deletions
diff --git a/drivers/dma/iop-adma.c b/drivers/dma/iop-adma.c new file mode 100644 index 00000000000..5a1d426744d --- /dev/null +++ b/drivers/dma/iop-adma.c @@ -0,0 +1,1467 @@ +/* + * offload engine driver for the Intel Xscale series of i/o processors + * Copyright © 2006, Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. + * + */ + +/* + * This driver supports the asynchrounous DMA copy and RAID engines available + * on the Intel Xscale(R) family of I/O Processors (IOP 32x, 33x, 134x) + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/async_tx.h> +#include <linux/delay.h> +#include <linux/dma-mapping.h> +#include <linux/spinlock.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/memory.h> +#include <linux/ioport.h> + +#include <asm/arch/adma.h> + +#define to_iop_adma_chan(chan) container_of(chan, struct iop_adma_chan, common) +#define to_iop_adma_device(dev) \ + container_of(dev, struct iop_adma_device, common) +#define tx_to_iop_adma_slot(tx) \ + container_of(tx, struct iop_adma_desc_slot, async_tx) + +/** + * iop_adma_free_slots - flags descriptor slots for reuse + * @slot: Slot to free + * Caller must hold &iop_chan->lock while calling this function + */ +static void iop_adma_free_slots(struct iop_adma_desc_slot *slot) +{ + int stride = slot->slots_per_op; + + while (stride--) { + slot->slots_per_op = 0; + slot = list_entry(slot->slot_node.next, + struct iop_adma_desc_slot, + slot_node); + } +} + +static dma_cookie_t +iop_adma_run_tx_complete_actions(struct iop_adma_desc_slot *desc, + struct iop_adma_chan *iop_chan, dma_cookie_t cookie) +{ + BUG_ON(desc->async_tx.cookie < 0); + spin_lock_bh(&desc->async_tx.lock); + if (desc->async_tx.cookie > 0) { + cookie = desc->async_tx.cookie; + desc->async_tx.cookie = 0; + + /* call the callback (must not sleep or submit new + * operations to this channel) + */ + if (desc->async_tx.callback) + desc->async_tx.callback( + desc->async_tx.callback_param); + + /* unmap dma addresses + * (unmap_single vs unmap_page?) + */ + if (desc->group_head && desc->unmap_len) { + struct iop_adma_desc_slot *unmap = desc->group_head; + struct device *dev = + &iop_chan->device->pdev->dev; + u32 len = unmap->unmap_len; + u32 src_cnt = unmap->unmap_src_cnt; + dma_addr_t addr = iop_desc_get_dest_addr(unmap, + iop_chan); + + dma_unmap_page(dev, addr, len, DMA_FROM_DEVICE); + while (src_cnt--) { + addr = iop_desc_get_src_addr(unmap, + iop_chan, + src_cnt); + dma_unmap_page(dev, addr, len, + DMA_TO_DEVICE); + } + desc->group_head = NULL; + } + } + + /* run dependent operations */ + async_tx_run_dependencies(&desc->async_tx); + spin_unlock_bh(&desc->async_tx.lock); + + return cookie; +} + +static int +iop_adma_clean_slot(struct iop_adma_desc_slot *desc, + struct iop_adma_chan *iop_chan) +{ + /* the client is allowed to attach dependent operations + * until 'ack' is set + */ + if (!desc->async_tx.ack) + return 0; + + /* leave the last descriptor in the chain + * so we can append to it + */ + if (desc->chain_node.next == &iop_chan->chain) + return 1; + + dev_dbg(iop_chan->device->common.dev, + "\tfree slot: %d slots_per_op: %d\n", + desc->idx, desc->slots_per_op); + + list_del(&desc->chain_node); + iop_adma_free_slots(desc); + + return 0; +} + +static void __iop_adma_slot_cleanup(struct iop_adma_chan *iop_chan) +{ + struct iop_adma_desc_slot *iter, *_iter, *grp_start = NULL; + dma_cookie_t cookie = 0; + u32 current_desc = iop_chan_get_current_descriptor(iop_chan); + int busy = iop_chan_is_busy(iop_chan); + int seen_current = 0, slot_cnt = 0, slots_per_op = 0; + + dev_dbg(iop_chan->device->common.dev, "%s\n", __FUNCTION__); + /* free completed slots from the chain starting with + * the oldest descriptor + */ + list_for_each_entry_safe(iter, _iter, &iop_chan->chain, + chain_node) { + pr_debug("\tcookie: %d slot: %d busy: %d " + "this_desc: %#x next_desc: %#x ack: %d\n", + iter->async_tx.cookie, iter->idx, busy, + iter->async_tx.phys, iop_desc_get_next_desc(iter), + iter->async_tx.ack); + prefetch(_iter); + prefetch(&_iter->async_tx); + + /* do not advance past the current descriptor loaded into the + * hardware channel, subsequent descriptors are either in + * process or have not been submitted + */ + if (seen_current) + break; + + /* stop the search if we reach the current descriptor and the + * channel is busy, or if it appears that the current descriptor + * needs to be re-read (i.e. has been appended to) + */ + if (iter->async_tx.phys == current_desc) { + BUG_ON(seen_current++); + if (busy || iop_desc_get_next_desc(iter)) + break; + } + + /* detect the start of a group transaction */ + if (!slot_cnt && !slots_per_op) { + slot_cnt = iter->slot_cnt; + slots_per_op = iter->slots_per_op; + if (slot_cnt <= slots_per_op) { + slot_cnt = 0; + slots_per_op = 0; + } + } + + if (slot_cnt) { + pr_debug("\tgroup++\n"); + if (!grp_start) + grp_start = iter; + slot_cnt -= slots_per_op; + } + + /* all the members of a group are complete */ + if (slots_per_op != 0 && slot_cnt == 0) { + struct iop_adma_desc_slot *grp_iter, *_grp_iter; + int end_of_chain = 0; + pr_debug("\tgroup end\n"); + + /* collect the total results */ + if (grp_start->xor_check_result) { + u32 zero_sum_result = 0; + slot_cnt = grp_start->slot_cnt; + grp_iter = grp_start; + + list_for_each_entry_from(grp_iter, + &iop_chan->chain, chain_node) { + zero_sum_result |= + iop_desc_get_zero_result(grp_iter); + pr_debug("\titer%d result: %d\n", + grp_iter->idx, zero_sum_result); + slot_cnt -= slots_per_op; + if (slot_cnt == 0) + break; + } + pr_debug("\tgrp_start->xor_check_result: %p\n", + grp_start->xor_check_result); + *grp_start->xor_check_result = zero_sum_result; + } + + /* clean up the group */ + slot_cnt = grp_start->slot_cnt; + grp_iter = grp_start; + list_for_each_entry_safe_from(grp_iter, _grp_iter, + &iop_chan->chain, chain_node) { + cookie = iop_adma_run_tx_complete_actions( + grp_iter, iop_chan, cookie); + + slot_cnt -= slots_per_op; + end_of_chain = iop_adma_clean_slot(grp_iter, + iop_chan); + + if (slot_cnt == 0 || end_of_chain) + break; + } + + /* the group should be complete at this point */ + BUG_ON(slot_cnt); + + slots_per_op = 0; + grp_start = NULL; + if (end_of_chain) + break; + else + continue; + } else if (slots_per_op) /* wait for group completion */ + continue; + + /* write back zero sum results (single descriptor case) */ + if (iter->xor_check_result && iter->async_tx.cookie) + *iter->xor_check_result = + iop_desc_get_zero_result(iter); + + cookie = iop_adma_run_tx_complete_actions( + iter, iop_chan, cookie); + + if (iop_adma_clean_slot(iter, iop_chan)) + break; + } + + BUG_ON(!seen_current); + + iop_chan_idle(busy, iop_chan); + + if (cookie > 0) { + iop_chan->completed_cookie = cookie; + pr_debug("\tcompleted cookie %d\n", cookie); + } +} + +static void +iop_adma_slot_cleanup(struct iop_adma_chan *iop_chan) +{ + spin_lock_bh(&iop_chan->lock); + __iop_adma_slot_cleanup(iop_chan); + spin_unlock_bh(&iop_chan->lock); +} + +static void iop_adma_tasklet(unsigned long data) +{ + struct iop_adma_chan *chan = (struct iop_adma_chan *) data; + __iop_adma_slot_cleanup(chan); +} + +static struct iop_adma_desc_slot * +iop_adma_alloc_slots(struct iop_adma_chan *iop_chan, int num_slots, + int slots_per_op) +{ + struct iop_adma_desc_slot *iter, *_iter, *alloc_start = NULL; + struct list_head chain = LIST_HEAD_INIT(chain); + int slots_found, retry = 0; + + /* start search from the last allocated descrtiptor + * if a contiguous allocation can not be found start searching + * from the beginning of the list + */ +retry: + slots_found = 0; + if (retry == 0) + iter = iop_chan->last_used; + else + iter = list_entry(&iop_chan->all_slots, + struct iop_adma_desc_slot, + slot_node); + + list_for_each_entry_safe_continue( + iter, _iter, &iop_chan->all_slots, slot_node) { + prefetch(_iter); + prefetch(&_iter->async_tx); + if (iter->slots_per_op) { + /* give up after finding the first busy slot + * on the second pass through the list + */ + if (retry) + break; + + slots_found = 0; + continue; + } + + /* start the allocation if the slot is correctly aligned */ + if (!slots_found++) { + if (iop_desc_is_aligned(iter, slots_per_op)) + alloc_start = iter; + else { + slots_found = 0; + continue; + } + } + + if (slots_found == num_slots) { + struct iop_adma_desc_slot *alloc_tail = NULL; + struct iop_adma_desc_slot *last_used = NULL; + iter = alloc_start; + while (num_slots) { + int i; + dev_dbg(iop_chan->device->common.dev, + "allocated slot: %d " + "(desc %p phys: %#x) slots_per_op %d\n", + iter->idx, iter->hw_desc, + iter->async_tx.phys, slots_per_op); + + /* pre-ack all but the last descriptor */ + if (num_slots != slots_per_op) + iter->async_tx.ack = 1; + else + iter->async_tx.ack = 0; + + list_add_tail(&iter->chain_node, &chain); + alloc_tail = iter; + iter->async_tx.cookie = 0; + iter->slot_cnt = num_slots; + iter->xor_check_result = NULL; + for (i = 0; i < slots_per_op; i++) { + iter->slots_per_op = slots_per_op - i; + last_used = iter; + iter = list_entry(iter->slot_node.next, + struct iop_adma_desc_slot, + slot_node); + } + num_slots -= slots_per_op; + } + alloc_tail->group_head = alloc_start; + alloc_tail->async_tx.cookie = -EBUSY; + list_splice(&chain, &alloc_tail->async_tx.tx_list); + iop_chan->last_used = last_used; + iop_desc_clear_next_desc(alloc_start); + iop_desc_clear_next_desc(alloc_tail); + return alloc_tail; + } + } + if (!retry++) + goto retry; + + /* try to free some slots if the allocation fails */ + tasklet_schedule(&iop_chan->irq_tasklet); + + return NULL; +} + +static dma_cookie_t +iop_desc_assign_cookie(struct iop_adma_chan *iop_chan, + struct iop_adma_desc_slot *desc) +{ + dma_cookie_t cookie = iop_chan->common.cookie; + cookie++; + if (cookie < 0) + cookie = 1; + iop_chan->common.cookie = desc->async_tx.cookie = cookie; + return cookie; +} + +static void iop_adma_check_threshold(struct iop_adma_chan *iop_chan) +{ + dev_dbg(iop_chan->device->common.dev, "pending: %d\n", + iop_chan->pending); + + if (iop_chan->pending >= IOP_ADMA_THRESHOLD) { + iop_chan->pending = 0; + iop_chan_append(iop_chan); + } +} + +static dma_cookie_t +iop_adma_tx_submit(struct dma_async_tx_descriptor *tx) +{ + struct iop_adma_desc_slot *sw_desc = tx_to_iop_adma_slot(tx); + struct iop_adma_chan *iop_chan = to_iop_adma_chan(tx->chan); + struct iop_adma_desc_slot *grp_start, *old_chain_tail; + int slot_cnt; + int slots_per_op; + dma_cookie_t cookie; + + grp_start = sw_desc->group_head; + slot_cnt = grp_start->slot_cnt; + slots_per_op = grp_start->slots_per_op; + + spin_lock_bh(&iop_chan->lock); + cookie = iop_desc_assign_cookie(iop_chan, sw_desc); + + old_chain_tail = list_entry(iop_chan->chain.prev, + struct iop_adma_desc_slot, chain_node); + list_splice_init(&sw_desc->async_tx.tx_list, + &old_chain_tail->chain_node); + + /* fix up the hardware chain */ + iop_desc_set_next_desc(old_chain_tail, grp_start->async_tx.phys); + + /* 1/ don't add pre-chained descriptors + * 2/ dummy read to flush next_desc write + */ + BUG_ON(iop_desc_get_next_desc(sw_desc)); + + /* increment the pending count by the number of slots + * memcpy operations have a 1:1 (slot:operation) relation + * other operations are heavier and will pop the threshold + * more often. + */ + iop_chan->pending += slot_cnt; + iop_adma_check_threshold(iop_chan); + spin_unlock_bh(&iop_chan->lock); + + dev_dbg(iop_chan->device->common.dev, "%s cookie: %d slot: %d\n", + __FUNCTION__, sw_desc->async_tx.cookie, sw_desc->idx); + + return cookie; +} + +static void +iop_adma_set_dest(dma_addr_t addr, struct dma_async_tx_descriptor *tx, + int index) +{ + struct iop_adma_desc_slot *sw_desc = tx_to_iop_adma_slot(tx); + struct iop_adma_chan *iop_chan = to_iop_adma_chan(tx->chan); + + /* to do: support transfers lengths > IOP_ADMA_MAX_BYTE_COUNT */ + iop_desc_set_dest_addr(sw_desc->group_head, iop_chan, addr); +} + +static void iop_chan_start_null_memcpy(struct iop_adma_chan *iop_chan); +static void iop_chan_start_null_xor(struct iop_adma_chan *iop_chan); + +/* returns the number of allocated descriptors */ +static int iop_adma_alloc_chan_resources(struct dma_chan *chan) +{ + char *hw_desc; + int idx; + struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan); + struct iop_adma_desc_slot *slot = NULL; + int init = iop_chan->slots_allocated ? 0 : 1; + struct iop_adma_platform_data *plat_data = + iop_chan->device->pdev->dev.platform_data; + int num_descs_in_pool = plat_data->pool_size/IOP_ADMA_SLOT_SIZE; + + /* Allocate descriptor slots */ + do { + idx = iop_chan->slots_allocated; + if (idx == num_descs_in_pool) + break; + + slot = kzalloc(sizeof(*slot), GFP_KERNEL); + if (!slot) { + printk(KERN_INFO "IOP ADMA Channel only initialized" + " %d descriptor slots", idx); + break; + } + hw_desc = (char *) iop_chan->device->dma_desc_pool_virt; + slot->hw_desc = (void *) &hw_desc[idx * IOP_ADMA_SLOT_SIZE]; + + dma_async_tx_descriptor_init(&slot->async_tx, chan); + slot->async_tx.tx_submit = iop_adma_tx_submit; + slot->async_tx.tx_set_dest = iop_adma_set_dest; + INIT_LIST_HEAD(&slot->chain_node); + INIT_LIST_HEAD(&slot->slot_node); + INIT_LIST_HEAD(&slot->async_tx.tx_list); + hw_desc = (char *) iop_chan->device->dma_desc_pool; + slot->async_tx.phys = + (dma_addr_t) &hw_desc[idx * IOP_ADMA_SLOT_SIZE]; + slot->idx = idx; + + spin_lock_bh(&iop_chan->lock); + iop_chan->slots_allocated++; + list_add_tail(&slot->slot_node, &iop_chan->all_slots); + spin_unlock_bh(&iop_chan->lock); + } while (iop_chan->slots_allocated < num_descs_in_pool); + + if (idx && !iop_chan->last_used) + iop_chan->last_used = list_entry(iop_chan->all_slots.next, + struct iop_adma_desc_slot, + slot_node); + + dev_dbg(iop_chan->device->common.dev, + "allocated %d descriptor slots last_used: %p\n", + iop_chan->slots_allocated, iop_chan->last_used); + + /* initialize the channel and the chain with a null operation */ + if (init) { + if (dma_has_cap(DMA_MEMCPY, + iop_chan->device->common.cap_mask)) + iop_chan_start_null_memcpy(iop_chan); + else if (dma_has_cap(DMA_XOR, + iop_chan->device->common.cap_mask)) + iop_chan_start_null_xor(iop_chan); + else + BUG(); + } + + return (idx > 0) ? idx : -ENOMEM; +} + +static struct dma_async_tx_descriptor * +iop_adma_prep_dma_interrupt(struct dma_chan *chan) +{ + struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan); + struct iop_adma_desc_slot *sw_desc, *grp_start; + int slot_cnt, slots_per_op; + + dev_dbg(iop_chan->device->common.dev, "%s\n", __FUNCTION__); + + spin_lock_bh(&iop_chan->lock); + slot_cnt = iop_chan_interrupt_slot_count(&slots_per_op, iop_chan); + sw_desc = iop_adma_alloc_slots(iop_chan, slot_cnt, slots_per_op); + if (sw_desc) { + grp_start = sw_desc->group_head; + iop_desc_init_interrupt(grp_start, iop_chan); + grp_start->unmap_len = 0; + } + spin_unlock_bh(&iop_chan->lock); + + return sw_desc ? &sw_desc->async_tx : NULL; +} + +static void +iop_adma_memcpy_set_src(dma_addr_t addr, struct dma_async_tx_descriptor *tx, + int index) +{ + struct iop_adma_desc_slot *sw_desc = tx_to_iop_adma_slot(tx); + struct iop_adma_desc_slot *grp_start = sw_desc->group_head; + + iop_desc_set_memcpy_src_addr(grp_start, addr); +} + +static struct dma_async_tx_descriptor * +iop_adma_prep_dma_memcpy(struct dma_chan *chan, size_t len, int int_en) +{ + struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan); + struct iop_adma_desc_slot *sw_desc, *grp_start; + int slot_cnt, slots_per_op; + + if (unlikely(!len)) + return NULL; + BUG_ON(unlikely(len > IOP_ADMA_MAX_BYTE_COUNT)); + + dev_dbg(iop_chan->device->common.dev, "%s len: %u\n", + __FUNCTION__, len); + + spin_lock_bh(&iop_chan->lock); + slot_cnt = iop_chan_memcpy_slot_count(len, &slots_per_op); + sw_desc = iop_adma_alloc_slots(iop_chan, slot_cnt, slots_per_op); + if (sw_desc) { + grp_start = sw_desc->group_head; + iop_desc_init_memcpy(grp_start, int_en); + iop_desc_set_byte_count(grp_start, iop_chan, len); + sw_desc->unmap_src_cnt = 1; + sw_desc->unmap_len = len; + sw_desc->async_tx.tx_set_src = iop_adma_memcpy_set_src; + } + spin_unlock_bh(&iop_chan->lock); + + return sw_desc ? &sw_desc->async_tx : NULL; +} + +static struct dma_async_tx_descriptor * +iop_adma_prep_dma_memset(struct dma_chan *chan, int value, size_t len, + int int_en) +{ + struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan); + struct iop_adma_desc_slot *sw_desc, *grp_start; + int slot_cnt, slots_per_op; + + if (unlikely(!len)) + return NULL; + BUG_ON(unlikely(len > IOP_ADMA_MAX_BYTE_COUNT)); + + dev_dbg(iop_chan->device->common.dev, "%s len: %u\n", + __FUNCTION__, len); + + spin_lock_bh(&iop_chan->lock); + slot_cnt = iop_chan_memset_slot_count(len, &slots_per_op); + sw_desc = iop_adma_alloc_slots(iop_chan, slot_cnt, slots_per_op); + if (sw_desc) { + grp_start = sw_desc->group_head; + iop_desc_init_memset(grp_start, int_en); + iop_desc_set_byte_count(grp_start, iop_chan, len); + iop_desc_set_block_fill_val(grp_start, value); + sw_desc->unmap_src_cnt = 1; + sw_desc->unmap_len = len; + } + spin_unlock_bh(&iop_chan->lock); + + return sw_desc ? &sw_desc->async_tx : NULL; +} + +static void +iop_adma_xor_set_src(dma_addr_t addr, struct dma_async_tx_descriptor *tx, + int index) +{ + struct iop_adma_desc_slot *sw_desc = tx_to_iop_adma_slot(tx); + struct iop_adma_desc_slot *grp_start = sw_desc->group_head; + + iop_desc_set_xor_src_addr(grp_start, index, addr); +} + +static struct dma_async_tx_descriptor * +iop_adma_prep_dma_xor(struct dma_chan *chan, unsigned int src_cnt, size_t len, + int int_en) +{ + struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan); + struct iop_adma_desc_slot *sw_desc, *grp_start; + int slot_cnt, slots_per_op; + + if (unlikely(!len)) + return NULL; + BUG_ON(unlikely(len > IOP_ADMA_XOR_MAX_BYTE_COUNT)); + + dev_dbg(iop_chan->device->common.dev, + "%s src_cnt: %d len: %u int_en: %d\n", + __FUNCTION__, src_cnt, len, int_en); + + spin_lock_bh(&iop_chan->lock); + slot_cnt = iop_chan_xor_slot_count(len, src_cnt, &slots_per_op); + sw_desc = iop_adma_alloc_slots(iop_chan, slot_cnt, slots_per_op); + if (sw_desc) { + grp_start = sw_desc->group_head; + iop_desc_init_xor(grp_start, src_cnt, int_en); + iop_desc_set_byte_count(grp_start, iop_chan, len); + sw_desc->unmap_src_cnt = src_cnt; + sw_desc->unmap_len = len; + sw_desc->async_tx.tx_set_src = iop_adma_xor_set_src; + } + spin_unlock_bh(&iop_chan->lock); + + return sw_desc ? &sw_desc->async_tx : NULL; +} + +static void +iop_adma_xor_zero_sum_set_src(dma_addr_t addr, + struct dma_async_tx_descriptor *tx, + int index) +{ + struct iop_adma_desc_slot *sw_desc = tx_to_iop_adma_slot(tx); + struct iop_adma_desc_slot *grp_start = sw_desc->group_head; + + iop_desc_set_zero_sum_src_addr(grp_start, index, addr); +} + +static struct dma_async_tx_descriptor * +iop_adma_prep_dma_zero_sum(struct dma_chan *chan, unsigned int src_cnt, + size_t len, u32 *result, int int_en) +{ + struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan); + struct iop_adma_desc_slot *sw_desc, *grp_start; + int slot_cnt, slots_per_op; + + if (unlikely(!len)) + return NULL; + + dev_dbg(iop_chan->device->common.dev, "%s src_cnt: %d len: %u\n", + __FUNCTION__, src_cnt, len); + + spin_lock_bh(&iop_chan->lock); + slot_cnt = iop_chan_zero_sum_slot_count(len, src_cnt, &slots_per_op); + sw_desc = iop_adma_alloc_slots(iop_chan, slot_cnt, slots_per_op); + if (sw_desc) { + grp_start = sw_desc->group_head; + iop_desc_init_zero_sum(grp_start, src_cnt, int_en); + iop_desc_set_zero_sum_byte_count(grp_start, len); + grp_start->xor_check_result = result; + pr_debug("\t%s: grp_start->xor_check_result: %p\n", + __FUNCTION__, grp_start->xor_check_result); + sw_desc->unmap_src_cnt = src_cnt; + sw_desc->unmap_len = len; + sw_desc->async_tx.tx_set_src = iop_adma_xor_zero_sum_set_src; + } + spin_unlock_bh(&iop_chan->lock); + + return sw_desc ? &sw_desc->async_tx : NULL; +} + +static void iop_adma_dependency_added(struct dma_chan *chan) +{ + struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan); + tasklet_schedule(&iop_chan->irq_tasklet); +} + +static void iop_adma_free_chan_resources(struct dma_chan *chan) +{ + struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan); + struct iop_adma_desc_slot *iter, *_iter; + int in_use_descs = 0; + + iop_adma_slot_cleanup(iop_chan); + + spin_lock_bh(&iop_chan->lock); + list_for_each_entry_safe(iter, _iter, &iop_chan->chain, + chain_node) { + in_use_descs++; + list_del(&iter->chain_node); + } + list_for_each_entry_safe_reverse( + iter, _iter, &iop_chan->all_slots, slot_node) { + list_del(&iter->slot_node); + kfree(iter); + iop_chan->slots_allocated--; + } + iop_chan->last_used = NULL; + + dev_dbg(iop_chan->device->common.dev, "%s slots_allocated %d\n", + __FUNCTION__, iop_chan->slots_allocated); + spin_unlock_bh(&iop_chan->lock); + + /* one is ok since we left it on there on purpose */ + if (in_use_descs > 1) + printk(KERN_ERR "IOP: Freeing %d in use descriptors!\n", + in_use_descs - 1); +} + +/** + * iop_adma_is_complete - poll the status of an ADMA transaction + * @chan: ADMA channel handle + * @cookie: ADMA transaction identifier + */ +static enum dma_status iop_adma_is_complete(struct dma_chan *chan, + dma_cookie_t cookie, + dma_cookie_t *done, + dma_cookie_t *used) +{ + struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan); + dma_cookie_t last_used; + dma_cookie_t last_complete; + enum dma_status ret; + + last_used = chan->cookie; + last_complete = iop_chan->completed_cookie; + + if (done) + *done = last_complete; + if (used) + *used = last_used; + + ret = dma_async_is_complete(cookie, last_complete, last_used); + if (ret == DMA_SUCCESS) + return ret; + + iop_adma_slot_cleanup(iop_chan); + + last_used = chan->cookie; + last_complete = iop_chan->completed_cookie; + + if (done) + *done = last_complete; + if (used) + *used = last_used; + + return dma_async_is_complete(cookie, last_complete, last_used); +} + +static irqreturn_t iop_adma_eot_handler(int irq, void *data) +{ + struct iop_adma_chan *chan = data; + + dev_dbg(chan->device->common.dev, "%s\n", __FUNCTION__); + + tasklet_schedule(&chan->irq_tasklet); + + iop_adma_device_clear_eot_status(chan); + + return IRQ_HANDLED; +} + +static irqreturn_t iop_adma_eoc_handler(int irq, void *data) +{ + struct iop_adma_chan *chan = data; + + dev_dbg(chan->device->common.dev, "%s\n", __FUNCTION__); + + tasklet_schedule(&chan->irq_tasklet); + + iop_adma_device_clear_eoc_status(chan); + + return IRQ_HANDLED; +} + +static irqreturn_t iop_adma_err_handler(int irq, void *data) +{ + struct iop_adma_chan *chan = data; + unsigned long status = iop_chan_get_status(chan); + + dev_printk(KERN_ERR, chan->device->common.dev, + "error ( %s%s%s%s%s%s%s)\n", + iop_is_err_int_parity(status, chan) ? "int_parity " : "", + iop_is_err_mcu_abort(status, chan) ? "mcu_abort " : "", + iop_is_err_int_tabort(status, chan) ? "int_tabort " : "", + iop_is_err_int_mabort(status, chan) ? "int_mabort " : "", + iop_is_err_pci_tabort(status, chan) ? "pci_tabort " : "", + iop_is_err_pci_mabort(status, chan) ? "pci_mabort " : "", + iop_is_err_split_tx(status, chan) ? "split_tx " : ""); + + iop_adma_device_clear_err_status(chan); + + BUG(); + + return IRQ_HANDLED; +} + +static void iop_adma_issue_pending(struct dma_chan *chan) +{ + struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan); + + if (iop_chan->pending) { + iop_chan->pending = 0; + iop_chan_append(iop_chan); + } +} + +/* + * Perform a transaction to verify the HW works. + */ +#define IOP_ADMA_TEST_SIZE 2000 + +static int __devinit iop_adma_memcpy_self_test(struct iop_adma_device *device) +{ + int i; + void *src, *dest; + dma_addr_t src_dma, dest_dma; + struct dma_chan *dma_chan; + dma_cookie_t cookie; + struct dma_async_tx_descriptor *tx; + int err = 0; + struct iop_adma_chan *iop_chan; + + dev_dbg(device->common.dev, "%s\n", __FUNCTION__); + + src = kzalloc(sizeof(u8) * IOP_ADMA_TEST_SIZE, GFP_KERNEL); + if (!src) + return -ENOMEM; + dest = kzalloc(sizeof(u8) * IOP_ADMA_TEST_SIZE, GFP_KERNEL); + if (!dest) { + kfree(src); + return -ENOMEM; + } + + /* Fill in src buffer */ + for (i = 0; i < IOP_ADMA_TEST_SIZE; i++) + ((u8 *) src)[i] = (u8)i; + + memset(dest, 0, IOP_ADMA_TEST_SIZE); + + /* Start copy, using first DMA channel */ + dma_chan = container_of(device->common.channels.next, + struct dma_chan, + device_node); + if (iop_adma_alloc_chan_resources(dma_chan) < 1) { + err = -ENODEV; + goto out; + } + + tx = iop_adma_prep_dma_memcpy(dma_chan, IOP_ADMA_TEST_SIZE, 1); + dest_dma = dma_map_single(dma_chan->device->dev, dest, + IOP_ADMA_TEST_SIZE, DMA_FROM_DEVICE); + iop_adma_set_dest(dest_dma, tx, 0); + src_dma = dma_map_single(dma_chan->device->dev, src, + IOP_ADMA_TEST_SIZE, DMA_TO_DEVICE); + iop_adma_memcpy_set_src(src_dma, tx, 0); + + cookie = iop_adma_tx_submit(tx); + iop_adma_issue_pending(dma_chan); + async_tx_ack(tx); + msleep(1); + + if (iop_adma_is_complete(dma_chan, cookie, NULL, NULL) != + DMA_SUCCESS) { + dev_printk(KERN_ERR, dma_chan->device->dev, + "Self-test copy timed out, disabling\n"); + err = -ENODEV; + goto free_resources; + } + + iop_chan = to_iop_adma_chan(dma_chan); + dma_sync_single_for_cpu(&iop_chan->device->pdev->dev, dest_dma, + IOP_ADMA_TEST_SIZE, DMA_FROM_DEVICE); + if (memcmp(src, dest, IOP_ADMA_TEST_SIZE)) { + dev_printk(KERN_ERR, dma_chan->device->dev, + "Self-test copy failed compare, disabling\n"); + err = -ENODEV; + goto free_resources; + } + +free_resources: + iop_adma_free_chan_resources(dma_chan); +out: + kfree(src); + kfree(dest); + return err; +} + +#define IOP_ADMA_NUM_SRC_TEST 4 /* must be <= 15 */ +static int __devinit +iop_adma_xor_zero_sum_self_test(struct iop_adma_device *device) +{ + int i, src_idx; + struct page *dest; + struct page *xor_srcs[IOP_ADMA_NUM_SRC_TEST]; + struct page *zero_sum_srcs[IOP_ADMA_NUM_SRC_TEST + 1]; + dma_addr_t dma_addr, dest_dma; + struct dma_async_tx_descriptor *tx; + struct dma_chan *dma_chan; + dma_cookie_t cookie; + u8 cmp_byte = 0; + u32 cmp_word; + u32 zero_sum_result; + int err = 0; + struct iop_adma_chan *iop_chan; + + dev_dbg(device->common.dev, "%s\n", __FUNCTION__); + + for (src_idx = 0; src_idx < IOP_ADMA_NUM_SRC_TEST; src_idx++) { + xor_srcs[src_idx] = alloc_page(GFP_KERNEL); + if (!xor_srcs[src_idx]) + while (src_idx--) { + __free_page(xor_srcs[src_idx]); + return -ENOMEM; + } + } + + dest = alloc_page(GFP_KERNEL); + if (!dest) + while (src_idx--) { + __free_page(xor_srcs[src_idx]); + return -ENOMEM; + } + + /* Fill in src buffers */ + for (src_idx = 0; src_idx < IOP_ADMA_NUM_SRC_TEST; src_idx++) { + u8 *ptr = page_address(xor_srcs[src_idx]); + for (i = 0; i < PAGE_SIZE; i++) + ptr[i] = (1 << src_idx); + } + + for (src_idx = 0; src_idx < IOP_ADMA_NUM_SRC_TEST; src_idx++) + cmp_byte ^= (u8) (1 << src_idx); + + cmp_word = (cmp_byte << 24) | (cmp_byte << 16) | + (cmp_byte << 8) | cmp_byte; + + memset(page_address(dest), 0, PAGE_SIZE); + + dma_chan = container_of(device->common.channels.next, + struct dma_chan, + device_node); + if (iop_adma_alloc_chan_resources(dma_chan) < 1) { + err = -ENODEV; + goto out; + } + + /* test xor */ + tx = iop_adma_prep_dma_xor(dma_chan, IOP_ADMA_NUM_SRC_TEST, + PAGE_SIZE, 1); + dest_dma = dma_map_page(dma_chan->device->dev, dest, 0, + PAGE_SIZE, DMA_FROM_DEVICE); + iop_adma_set_dest(dest_dma, tx, 0); + + for (i = 0; i < IOP_ADMA_NUM_SRC_TEST; i++) { + dma_addr = dma_map_page(dma_chan->device->dev, xor_srcs[i], 0, + PAGE_SIZE, DMA_TO_DEVICE); + iop_adma_xor_set_src(dma_addr, tx, i); + } + + cookie = iop_adma_tx_submit(tx); + iop_adma_issue_pending(dma_chan); + async_tx_ack(tx); + msleep(8); + + if (iop_adma_is_complete(dma_chan, cookie, NULL, NULL) != + DMA_SUCCESS) { + dev_printk(KERN_ERR, dma_chan->device->dev, + "Self-test xor timed out, disabling\n"); + err = -ENODEV; + goto free_resources; + } + + iop_chan = to_iop_adma_chan(dma_chan); + dma_sync_single_for_cpu(&iop_chan->device->pdev->dev, dest_dma, + PAGE_SIZE, DMA_FROM_DEVICE); + for (i = 0; i < (PAGE_SIZE / sizeof(u32)); i++) { + u32 *ptr = page_address(dest); + if (ptr[i] != cmp_word) { + dev_printk(KERN_ERR, dma_chan->device->dev, + "Self-test xor failed compare, disabling\n"); + err = -ENODEV; + goto free_resources; + } + } + dma_sync_single_for_device(&iop_chan->device->pdev->dev, dest_dma, + PAGE_SIZE, DMA_TO_DEVICE); + + /* skip zero sum if the capability is not present */ + if (!dma_has_cap(DMA_ZERO_SUM, dma_chan->device->cap_mask)) + goto free_resources; + + /* zero sum the sources with the destintation page */ + for (i = 0; i < IOP_ADMA_NUM_SRC_TEST; i++) + zero_sum_srcs[i] = xor_srcs[i]; + zero_sum_srcs[i] = dest; + + zero_sum_result = 1; + + tx = iop_adma_prep_dma_zero_sum(dma_chan, IOP_ADMA_NUM_SRC_TEST + 1, + PAGE_SIZE, &zero_sum_result, 1); + for (i = 0; i < IOP_ADMA_NUM_SRC_TEST + 1; i++) { + dma_addr = dma_map_page(dma_chan->device->dev, zero_sum_srcs[i], + 0, PAGE_SIZE, DMA_TO_DEVICE); + iop_adma_xor_zero_sum_set_src(dma_addr, tx, i); + } + + cookie = iop_adma_tx_submit(tx); + iop_adma_issue_pending(dma_chan); + async_tx_ack(tx); + msleep(8); + + if (iop_adma_is_complete(dma_chan, cookie, NULL, NULL) != DMA_SUCCESS) { + dev_printk(KERN_ERR, dma_chan->device->dev, + "Self-test zero sum timed out, disabling\n"); + err = -ENODEV; + goto free_resources; + } + + if (zero_sum_result != 0) { + dev_printk(KERN_ERR, dma_chan->device->dev, + "Self-test zero sum failed compare, disabling\n"); + err = -ENODEV; + goto free_resources; + } + + /* test memset */ + tx = iop_adma_prep_dma_memset(dma_chan, 0, PAGE_SIZE, 1); + dma_addr = dma_map_page(dma_chan->device->dev, dest, 0, + PAGE_SIZE, DMA_FROM_DEVICE); + iop_adma_set_dest(dma_addr, tx, 0); + + cookie = iop_adma_tx_submit(tx); + iop_adma_issue_pending(dma_chan); + async_tx_ack(tx); + msleep(8); + + if (iop_adma_is_complete(dma_chan, cookie, NULL, NULL) != DMA_SUCCESS) { + dev_printk(KERN_ERR, dma_chan->device->dev, + "Self-test memset timed out, disabling\n"); + err = -ENODEV; + goto free_resources; + } + + for (i = 0; i < PAGE_SIZE/sizeof(u32); i++) { + u32 *ptr = page_address(dest); + if (ptr[i]) { + dev_printk(KERN_ERR, dma_chan->device->dev, + "Self-test memset failed compare, disabling\n"); + err = -ENODEV; + goto free_resources; + } + } + + /* test for non-zero parity sum */ + zero_sum_result = 0; + tx = iop_adma_prep_dma_zero_sum(dma_chan, IOP_ADMA_NUM_SRC_TEST + 1, + PAGE_SIZE, &zero_sum_result, 1); + for (i = 0; i < IOP_ADMA_NUM_SRC_TEST + 1; i++) { + dma_addr = dma_map_page(dma_chan->device->dev, zero_sum_srcs[i], + 0, PAGE_SIZE, DMA_TO_DEVICE); + iop_adma_xor_zero_sum_set_src(dma_addr, tx, i); + } + + cookie = iop_adma_tx_submit(tx); + iop_adma_issue_pending(dma_chan); + async_tx_ack(tx); + msleep(8); + + if (iop_adma_is_complete(dma_chan, cookie, NULL, NULL) != DMA_SUCCESS) { + dev_printk(KERN_ERR, dma_chan->device->dev, + "Self-test non-zero sum timed out, disabling\n"); + err = -ENODEV; + goto free_resources; + } + + if (zero_sum_result != 1) { + dev_printk(KERN_ERR, dma_chan->device->dev, + "Self-test non-zero sum failed compare, disabling\n"); + err = -ENODEV; + goto free_resources; + } + +free_resources: + iop_adma_free_chan_resources(dma_chan); +out: + src_idx = IOP_ADMA_NUM_SRC_TEST; + while (src_idx--) + __free_page(xor_srcs[src_idx]); + __free_page(dest); + return err; +} + +static int __devexit iop_adma_remove(struct platform_device *dev) +{ + struct iop_adma_device *device = platform_get_drvdata(dev); + struct dma_chan *chan, *_chan; + struct iop_adma_chan *iop_chan; + int i; + struct iop_adma_platform_data *plat_data = dev->dev.platform_data; + + dma_async_device_unregister(&device->common); + + for (i = 0; i < 3; i++) { + unsigned int irq; + irq = platform_get_irq(dev, i); + free_irq(irq, device); + } + + dma_free_coherent(&dev->dev, plat_data->pool_size, + device->dma_desc_pool_virt, device->dma_desc_pool); + + do { + struct resource *res; + res = platform_get_resource(dev, IORESOURCE_MEM, 0); + release_mem_region(res->start, res->end - res->start); + } while (0); + + list_for_each_entry_safe(chan, _chan, &device->common.channels, + device_node) { + iop_chan = to_iop_adma_chan(chan); + list_del(&chan->device_node); + kfree(iop_chan); + } + kfree(device); + + return 0; +} + +static int __devinit iop_adma_probe(struct platform_device *pdev) +{ + struct resource *res; + int ret = 0, i; + struct iop_adma_device *adev; + struct iop_adma_chan *iop_chan; + struct dma_device *dma_dev; + struct iop_adma_platform_data *plat_data = pdev->dev.platform_data; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return -ENODEV; + + if (!devm_request_mem_region(&pdev->dev, res->start, + res->end - res->start, pdev->name)) + return -EBUSY; + + adev = kzalloc(sizeof(*adev), GFP_KERNEL); + if (!adev) + return -ENOMEM; + dma_dev = &adev->common; + + /* allocate coherent memory for hardware descriptors + * note: writecombine gives slightly better performance, but + * requires that we explicitly flush the writes + */ + if ((adev->dma_desc_pool_virt = dma_alloc_writecombine(&pdev->dev, + plat_data->pool_size, + &adev->dma_desc_pool, + GFP_KERNEL)) == NULL) { + ret = -ENOMEM; + goto err_free_adev; + } + + dev_dbg(&pdev->dev, "%s: allocted descriptor pool virt %p phys %p\n", + __FUNCTION__, adev->dma_desc_pool_virt, + (void *) adev->dma_desc_pool); + + adev->id = plat_data->hw_id; + + /* discover transaction capabilites from the platform data */ + dma_dev->cap_mask = plat_data->cap_mask; + + adev->pdev = pdev; + platform_set_drvdata(pdev, adev); + + INIT_LIST_HEAD(&dma_dev->channels); + + /* set base routines */ + dma_dev->device_alloc_chan_resources = iop_adma_alloc_chan_resources; + dma_dev->device_free_chan_resources = iop_adma_free_chan_resources; + dma_dev->device_is_tx_complete = iop_adma_is_complete; + dma_dev->device_issue_pending = iop_adma_issue_pending; + dma_dev->device_dependency_added = iop_adma_dependency_added; + dma_dev->dev = &pdev->dev; + + /* set prep routines based on capability */ + if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask)) + dma_dev->device_prep_dma_memcpy = iop_adma_prep_dma_memcpy; + if (dma_has_cap(DMA_MEMSET, dma_dev->cap_mask)) + dma_dev->device_prep_dma_memset = iop_adma_prep_dma_memset; + if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) { + dma_dev->max_xor = iop_adma_get_max_xor(); + dma_dev->device_prep_dma_xor = iop_adma_prep_dma_xor; + } + if (dma_has_cap(DMA_ZERO_SUM, dma_dev->cap_mask)) + dma_dev->device_prep_dma_zero_sum = + iop_adma_prep_dma_zero_sum; + if (dma_has_cap(DMA_INTERRUPT, dma_dev->cap_mask)) + dma_dev->device_prep_dma_interrupt = + iop_adma_prep_dma_interrupt; + + iop_chan = kzalloc(sizeof(*iop_chan), GFP_KERNEL); + if (!iop_chan) { + ret = -ENOMEM; + goto err_free_dma; + } + iop_chan->device = adev; + + iop_chan->mmr_base = devm_ioremap(&pdev->dev, res->start, + res->end - res->start); + if (!iop_chan->mmr_base) { + ret = -ENOMEM; + goto err_free_iop_chan; + } + tasklet_init(&iop_chan->irq_tasklet, iop_adma_tasklet, (unsigned long) + iop_chan); + + /* clear errors before enabling interrupts */ + iop_adma_device_clear_err_status(iop_chan); + + for (i = 0; i < 3; i++) { + irq_handler_t handler[] = { iop_adma_eot_handler, + iop_adma_eoc_handler, + iop_adma_err_handler }; + int irq = platform_get_irq(pdev, i); + if (irq < 0) { + ret = -ENXIO; + goto err_free_iop_chan; + } else { + ret = devm_request_irq(&pdev->dev, irq, + handler[i], 0, pdev->name, iop_chan); + if (ret) + goto err_free_iop_chan; + } + } + + spin_lock_init(&iop_chan->lock); + init_timer(&iop_chan->cleanup_watchdog); + iop_chan->cleanup_watchdog.data = (unsigned long) iop_chan; + iop_chan->cleanup_watchdog.function = iop_adma_tasklet; + INIT_LIST_HEAD(&iop_chan->chain); + INIT_LIST_HEAD(&iop_chan->all_slots); + INIT_RCU_HEAD(&iop_chan->common.rcu); + iop_chan->common.device = dma_dev; + list_add_tail(&iop_chan->common.device_node, &dma_dev->channels); + + if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask)) { + ret = iop_adma_memcpy_self_test(adev); + dev_dbg(&pdev->dev, "memcpy self test returned %d\n", ret); + if (ret) + goto err_free_iop_chan; + } + + if (dma_has_cap(DMA_XOR, dma_dev->cap_mask) || + dma_has_cap(DMA_MEMSET, dma_dev->cap_mask)) { + ret = iop_adma_xor_zero_sum_self_test(adev); + dev_dbg(&pdev->dev, "xor self test returned %d\n", ret); + if (ret) + goto err_free_iop_chan; + } + + dev_printk(KERN_INFO, &pdev->dev, "Intel(R) IOP: " + "( %s%s%s%s%s%s%s%s%s%s)\n", + dma_has_cap(DMA_PQ_XOR, dma_dev->cap_mask) ? "pq_xor " : "", + dma_has_cap(DMA_PQ_UPDATE, dma_dev->cap_mask) ? "pq_update " : "", + dma_has_cap(DMA_PQ_ZERO_SUM, dma_dev->cap_mask) ? "pq_zero_sum " : "", + dma_has_cap(DMA_XOR, dma_dev->cap_mask) ? "xor " : "", + dma_has_cap(DMA_DUAL_XOR, dma_dev->cap_mask) ? "dual_xor " : "", + dma_has_cap(DMA_ZERO_SUM, dma_dev->cap_mask) ? "xor_zero_sum " : "", + dma_has_cap(DMA_MEMSET, dma_dev->cap_mask) ? "fill " : "", + dma_has_cap(DMA_MEMCPY_CRC32C, dma_dev->cap_mask) ? "cpy+crc " : "", + dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask) ? "cpy " : "", + dma_has_cap(DMA_INTERRUPT, dma_dev->cap_mask) ? "intr " : ""); + + dma_async_device_register(dma_dev); + goto out; + + err_free_iop_chan: + kfree(iop_chan); + err_free_dma: + dma_free_coherent(&adev->pdev->dev, plat_data->pool_size, + adev->dma_desc_pool_virt, adev->dma_desc_pool); + err_free_adev: + kfree(adev); + out: + return ret; +} + +static void iop_chan_start_null_memcpy(struct iop_adma_chan *iop_chan) +{ + struct iop_adma_desc_slot *sw_desc, *grp_start; + dma_cookie_t cookie; + int slot_cnt, slots_per_op; + + dev_dbg(iop_chan->device->common.dev, "%s\n", __FUNCTION__); + + spin_lock_bh(&iop_chan->lock); + slot_cnt = iop_chan_memcpy_slot_count(0, &slots_per_op); + sw_desc = iop_adma_alloc_slots(iop_chan, slot_cnt, slots_per_op); + if (sw_desc) { + grp_start = sw_desc->group_head; + + list_splice_init(&sw_desc->async_tx.tx_list, &iop_chan->chain); + sw_desc->async_tx.ack = 1; + iop_desc_init_memcpy(grp_start, 0); + iop_desc_set_byte_count(grp_start, iop_chan, 0); + iop_desc_set_dest_addr(grp_start, iop_chan, 0); + iop_desc_set_memcpy_src_addr(grp_start, 0); + + cookie = iop_chan->common.cookie; + cookie++; + if (cookie <= 1) + cookie = 2; + + /* initialize the completed cookie to be less than + * the most recently used cookie + */ + iop_chan->completed_cookie = cookie - 1; + iop_chan->common.cookie = sw_desc->async_tx.cookie = cookie; + + /* channel should not be busy */ + BUG_ON(iop_chan_is_busy(iop_chan)); + + /* clear any prior error-status bits */ + iop_adma_device_clear_err_status(iop_chan); + + /* disable operation */ + iop_chan_disable(iop_chan); + + /* set the descriptor address */ + iop_chan_set_next_descriptor(iop_chan, sw_desc->async_tx.phys); + + /* 1/ don't add pre-chained descriptors + * 2/ dummy read to flush next_desc write + */ + BUG_ON(iop_desc_get_next_desc(sw_desc)); + + /* run the descriptor */ + iop_chan_enable(iop_chan); + } else + dev_printk(KERN_ERR, iop_chan->device->common.dev, + "failed to allocate null descriptor\n"); + spin_unlock_bh(&iop_chan->lock); +} + +static void iop_chan_start_null_xor(struct iop_adma_chan *iop_chan) +{ + struct iop_adma_desc_slot *sw_desc, *grp_start; + dma_cookie_t cookie; + int slot_cnt, slots_per_op; + + dev_dbg(iop_chan->device->common.dev, "%s\n", __FUNCTION__); + + spin_lock_bh(&iop_chan->lock); + slot_cnt = iop_chan_xor_slot_count(0, 2, &slots_per_op); + sw_desc = iop_adma_alloc_slots(iop_chan, slot_cnt, slots_per_op); + if (sw_desc) { + grp_start = sw_desc->group_head; + list_splice_init(&sw_desc->async_tx.tx_list, &iop_chan->chain); + sw_desc->async_tx.ack = 1; + iop_desc_init_null_xor(grp_start, 2, 0); + iop_desc_set_byte_count(grp_start, iop_chan, 0); + iop_desc_set_dest_addr(grp_start, iop_chan, 0); + iop_desc_set_xor_src_addr(grp_start, 0, 0); + iop_desc_set_xor_src_addr(grp_start, 1, 0); + + cookie = iop_chan->common.cookie; + cookie++; + if (cookie <= 1) + cookie = 2; + + /* initialize the completed cookie to be less than + * the most recently used cookie + */ + iop_chan->completed_cookie = cookie - 1; + iop_chan->common.cookie = sw_desc->async_tx.cookie = cookie; + + /* channel should not be busy */ + BUG_ON(iop_chan_is_busy(iop_chan)); + + /* clear any prior error-status bits */ + iop_adma_device_clear_err_status(iop_chan); + + /* disable operation */ + iop_chan_disable(iop_chan); + + /* set the descriptor address */ + iop_chan_set_next_descriptor(iop_chan, sw_desc->async_tx.phys); + + /* 1/ don't add pre-chained descriptors + * 2/ dummy read to flush next_desc write + */ + BUG_ON(iop_desc_get_next_desc(sw_desc)); + + /* run the descriptor */ + iop_chan_enable(iop_chan); + } else + dev_printk(KERN_ERR, iop_chan->device->common.dev, + "failed to allocate null descriptor\n"); + spin_unlock_bh(&iop_chan->lock); +} + +static struct platform_driver iop_adma_driver = { + .probe = iop_adma_probe, + .remove = iop_adma_remove, + .driver = { + .owner = THIS_MODULE, + .name = "iop-adma", + }, +}; + +static int __init iop_adma_init (void) +{ + /* it's currently unsafe to unload this module */ + /* if forced, worst case is that rmmod hangs */ + __unsafe(THIS_MODULE); + + return platform_driver_register(&iop_adma_driver); +} + +static void __exit iop_adma_exit (void) +{ + platform_driver_unregister(&iop_adma_driver); + return; +} + +module_init(iop_adma_init); +module_exit(iop_adma_exit); + +MODULE_AUTHOR("Intel Corporation"); +MODULE_DESCRIPTION("IOP ADMA Engine Driver"); +MODULE_LICENSE("GPL"); |