From 8cc13a09474bb30d15dbf449767bb6d0198a8bf8 Mon Sep 17 00:00:00 2001 From: David Vrabel Date: Wed, 17 Sep 2008 16:34:09 +0100 Subject: uwb: add the UWB stack (reservation manager) DRP and reservation management. Signed-off-by: David Vrabel --- drivers/uwb/drp-ie.c | 232 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 232 insertions(+) create mode 100644 drivers/uwb/drp-ie.c (limited to 'drivers/uwb/drp-ie.c') diff --git a/drivers/uwb/drp-ie.c b/drivers/uwb/drp-ie.c new file mode 100644 index 00000000000..882724c5f12 --- /dev/null +++ b/drivers/uwb/drp-ie.c @@ -0,0 +1,232 @@ +/* + * UWB DRP IE management. + * + * Copyright (C) 2005-2006 Intel Corporation + * Copyright (C) 2008 Cambridge Silicon Radio Ltd. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version + * 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that 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, see . + */ +#include +#include +#include +#include + +#include "uwb-internal.h" + +/* + * Allocate a DRP IE. + * + * To save having to free/allocate a DRP IE when its MAS changes, + * enough memory is allocated for the maxiumum number of DRP + * allocation fields. This gives an overhead per reservation of up to + * (UWB_NUM_ZONES - 1) * 4 = 60 octets. + */ +static struct uwb_ie_drp *uwb_drp_ie_alloc(void) +{ + struct uwb_ie_drp *drp_ie; + unsigned tiebreaker; + + drp_ie = kzalloc(sizeof(struct uwb_ie_drp) + + UWB_NUM_ZONES * sizeof(struct uwb_drp_alloc), + GFP_KERNEL); + if (drp_ie) { + drp_ie->hdr.element_id = UWB_IE_DRP; + + get_random_bytes(&tiebreaker, sizeof(unsigned)); + uwb_ie_drp_set_tiebreaker(drp_ie, tiebreaker & 1); + } + return drp_ie; +} + + +/* + * Fill a DRP IE's allocation fields from a MAS bitmap. + */ +static void uwb_drp_ie_from_bm(struct uwb_ie_drp *drp_ie, + struct uwb_mas_bm *mas) +{ + int z, i, num_fields = 0, next = 0; + struct uwb_drp_alloc *zones; + __le16 current_bmp; + DECLARE_BITMAP(tmp_bmp, UWB_NUM_MAS); + DECLARE_BITMAP(tmp_mas_bm, UWB_MAS_PER_ZONE); + + zones = drp_ie->allocs; + + bitmap_copy(tmp_bmp, mas->bm, UWB_NUM_MAS); + + /* Determine unique MAS bitmaps in zones from bitmap. */ + for (z = 0; z < UWB_NUM_ZONES; z++) { + bitmap_copy(tmp_mas_bm, tmp_bmp, UWB_MAS_PER_ZONE); + if (bitmap_weight(tmp_mas_bm, UWB_MAS_PER_ZONE) > 0) { + bool found = false; + current_bmp = (__le16) *tmp_mas_bm; + for (i = 0; i < next; i++) { + if (current_bmp == zones[i].mas_bm) { + zones[i].zone_bm |= 1 << z; + found = true; + break; + } + } + if (!found) { + num_fields++; + zones[next].zone_bm = 1 << z; + zones[next].mas_bm = current_bmp; + next++; + } + } + bitmap_shift_right(tmp_bmp, tmp_bmp, UWB_MAS_PER_ZONE, UWB_NUM_MAS); + } + + /* Store in format ready for transmission (le16). */ + for (i = 0; i < num_fields; i++) { + drp_ie->allocs[i].zone_bm = cpu_to_le16(zones[i].zone_bm); + drp_ie->allocs[i].mas_bm = cpu_to_le16(zones[i].mas_bm); + } + + drp_ie->hdr.length = sizeof(struct uwb_ie_drp) - sizeof(struct uwb_ie_hdr) + + num_fields * sizeof(struct uwb_drp_alloc); +} + +/** + * uwb_drp_ie_update - update a reservation's DRP IE + * @rsv: the reservation + */ +int uwb_drp_ie_update(struct uwb_rsv *rsv) +{ + struct device *dev = &rsv->rc->uwb_dev.dev; + struct uwb_ie_drp *drp_ie; + int reason_code, status; + + switch (rsv->state) { + case UWB_RSV_STATE_NONE: + kfree(rsv->drp_ie); + rsv->drp_ie = NULL; + return 0; + case UWB_RSV_STATE_O_INITIATED: + reason_code = UWB_DRP_REASON_ACCEPTED; + status = 0; + break; + case UWB_RSV_STATE_O_PENDING: + reason_code = UWB_DRP_REASON_ACCEPTED; + status = 0; + break; + case UWB_RSV_STATE_O_MODIFIED: + reason_code = UWB_DRP_REASON_MODIFIED; + status = 1; + break; + case UWB_RSV_STATE_O_ESTABLISHED: + reason_code = UWB_DRP_REASON_ACCEPTED; + status = 1; + break; + case UWB_RSV_STATE_T_ACCEPTED: + reason_code = UWB_DRP_REASON_ACCEPTED; + status = 1; + break; + case UWB_RSV_STATE_T_DENIED: + reason_code = UWB_DRP_REASON_DENIED; + status = 0; + break; + default: + dev_dbg(dev, "rsv with unhandled state (%d)\n", rsv->state); + return -EINVAL; + } + + if (rsv->drp_ie == NULL) { + rsv->drp_ie = uwb_drp_ie_alloc(); + if (rsv->drp_ie == NULL) + return -ENOMEM; + } + drp_ie = rsv->drp_ie; + + uwb_ie_drp_set_owner(drp_ie, uwb_rsv_is_owner(rsv)); + uwb_ie_drp_set_status(drp_ie, status); + uwb_ie_drp_set_reason_code(drp_ie, reason_code); + uwb_ie_drp_set_stream_index(drp_ie, rsv->stream); + uwb_ie_drp_set_type(drp_ie, rsv->type); + + if (uwb_rsv_is_owner(rsv)) { + switch (rsv->target.type) { + case UWB_RSV_TARGET_DEV: + drp_ie->dev_addr = rsv->target.dev->dev_addr; + break; + case UWB_RSV_TARGET_DEVADDR: + drp_ie->dev_addr = rsv->target.devaddr; + break; + } + } else + drp_ie->dev_addr = rsv->owner->dev_addr; + + uwb_drp_ie_from_bm(drp_ie, &rsv->mas); + + rsv->ie_valid = true; + return 0; +} + +/* + * Set MAS bits from given MAS bitmap in a single zone of large bitmap. + * + * We are given a zone id and the MAS bitmap of bits that need to be set in + * this zone. Note that this zone may already have bits set and this only + * adds settings - we cannot simply assign the MAS bitmap contents to the + * zone contents. We iterate over the the bits (MAS) in the zone and set the + * bits that are set in the given MAS bitmap. + */ +static +void uwb_drp_ie_single_zone_to_bm(struct uwb_mas_bm *bm, u8 zone, u16 mas_bm) +{ + int mas; + u16 mas_mask; + + for (mas = 0; mas < UWB_MAS_PER_ZONE; mas++) { + mas_mask = 1 << mas; + if (mas_bm & mas_mask) + set_bit(zone * UWB_NUM_ZONES + mas, bm->bm); + } +} + +/** + * uwb_drp_ie_zones_to_bm - convert DRP allocation fields to a bitmap + * @mas: MAS bitmap that will be populated to correspond to the + * allocation fields in the DRP IE + * @drp_ie: the DRP IE that contains the allocation fields. + * + * The input format is an array of MAS allocation fields (16 bit Zone + * bitmap, 16 bit MAS bitmap) as described in [ECMA-368] section + * 16.8.6. The output is a full 256 bit MAS bitmap. + * + * We go over all the allocation fields, for each allocation field we + * know which zones are impacted. We iterate over all the zones + * impacted and call a function that will set the correct MAS bits in + * each zone. + */ +void uwb_drp_ie_to_bm(struct uwb_mas_bm *bm, const struct uwb_ie_drp *drp_ie) +{ + int numallocs = (drp_ie->hdr.length - 4) / 4; + const struct uwb_drp_alloc *alloc; + int cnt; + u16 zone_bm, mas_bm; + u8 zone; + u16 zone_mask; + + for (cnt = 0; cnt < numallocs; cnt++) { + alloc = &drp_ie->allocs[cnt]; + zone_bm = le16_to_cpu(alloc->zone_bm); + mas_bm = le16_to_cpu(alloc->mas_bm); + for (zone = 0; zone < UWB_NUM_ZONES; zone++) { + zone_mask = 1 << zone; + if (zone_bm & zone_mask) + uwb_drp_ie_single_zone_to_bm(bm, zone, mas_bm); + } + } +} -- cgit v1.2.3