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msm: bam_dmux: Handle DMA Mapping Failure

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Handle and recover from transient SPS and DMA
mapping failures by:
  1) Handle queue_rx() failures
  2) Recover from failure by requeuing at next call
  3) Properly unmap DMA items for failures
  4) Log failures for later analysis

CRs-Fixed: 330039
Change-Id: I7c304921b7c4009d0c9733f317c2392241d51acc
Signed-off-by: Eric Holmberg <eholmber@codeaurora.org>
This commit is contained in:
Eric Holmberg
2012-01-20 14:19:00 -07:00
committed by Linux Build Service Account
parent d3cf8b7878
commit b5b08e5e0e
1 changed files with 91 additions and 35 deletions
Download Patch File Download Diff File Expand all files Collapse all files

126
arch/arm/mach-msm/bam_dmux.c
View File

@@ -165,6 +165,7 @@ static int polling_mode;
static LIST_HEAD(bam_rx_pool);
static DEFINE_MUTEX(bam_rx_pool_mutexlock);
static int bam_rx_pool_len;
static LIST_HEAD(bam_tx_pool);
static DEFINE_SPINLOCK(bam_tx_pool_spinlock);
@@ -362,36 +363,78 @@ static void queue_rx(void)
{
void *ptr;
struct rx_pkt_info *info;
if (in_global_reset)
return;
info = kmalloc(sizeof(struct rx_pkt_info), GFP_KERNEL);
if (!info) {
pr_err("%s: unable to alloc rx_pkt_info\n", __func__);
return;
}
INIT_WORK(&info->work, handle_bam_mux_cmd);
info->skb = __dev_alloc_skb(BUFFER_SIZE, GFP_KERNEL);
if (info->skb == NULL) {
pr_err("%s: unable to alloc skb\n", __func__);
kfree(info);
return;
}
ptr = skb_put(info->skb, BUFFER_SIZE);
int ret;
int rx_len_cached;
mutex_lock(&bam_rx_pool_mutexlock);
list_add_tail(&info->list_node, &bam_rx_pool);
rx_len_cached = bam_rx_pool_len;
mutex_unlock(&bam_rx_pool_mutexlock);
/* need a way to handle error case */
info->dma_address = dma_map_single(NULL, ptr, BUFFER_SIZE,
DMA_FROM_DEVICE);
sps_transfer_one(bam_rx_pipe, info->dma_address,
BUFFER_SIZE, info,
SPS_IOVEC_FLAG_INT | SPS_IOVEC_FLAG_EOT);
while (rx_len_cached < NUM_BUFFERS) {
if (in_global_reset)
goto fail;
info = kmalloc(sizeof(struct rx_pkt_info), GFP_KERNEL);
if (!info) {
pr_err("%s: unable to alloc rx_pkt_info\n", __func__);
goto fail;
}
INIT_WORK(&info->work, handle_bam_mux_cmd);
info->skb = __dev_alloc_skb(BUFFER_SIZE, GFP_KERNEL);
if (info->skb == NULL) {
DMUX_LOG_KERR("%s: unable to alloc skb\n", __func__);
goto fail_info;
}
ptr = skb_put(info->skb, BUFFER_SIZE);
info->dma_address = dma_map_single(NULL, ptr, BUFFER_SIZE,
DMA_FROM_DEVICE);
if (info->dma_address == 0 || info->dma_address == ~0) {
DMUX_LOG_KERR("%s: dma_map_single failure %p for %p\n",
__func__, (void *)info->dma_address, ptr);
goto fail_skb;
}
mutex_lock(&bam_rx_pool_mutexlock);
list_add_tail(&info->list_node, &bam_rx_pool);
rx_len_cached = ++bam_rx_pool_len;
mutex_unlock(&bam_rx_pool_mutexlock);
ret = sps_transfer_one(bam_rx_pipe, info->dma_address,
BUFFER_SIZE, info,
SPS_IOVEC_FLAG_INT | SPS_IOVEC_FLAG_EOT);
if (ret) {
DMUX_LOG_KERR("%s: sps_transfer_one failed %d\n",
__func__, ret);
goto fail_transfer;
}
}
return;
fail_transfer:
mutex_lock(&bam_rx_pool_mutexlock);
list_del(&info->list_node);
--bam_rx_pool_len;
rx_len_cached = bam_rx_pool_len;
mutex_unlock(&bam_rx_pool_mutexlock);
dma_unmap_single(NULL, info->dma_address, BUFFER_SIZE,
DMA_FROM_DEVICE);
fail_skb:
dev_kfree_skb_any(info->skb);
fail_info:
kfree(info);
fail:
if (rx_len_cached == 0) {
DMUX_LOG_KERR("%s: RX queue failure\n", __func__);
in_global_reset = 1;
}
}
static void bam_mux_process_data(struct sk_buff *rx_skb)
@@ -561,10 +604,14 @@ static int bam_mux_write_cmd(void *data, uint32_t len)
rc = sps_transfer_one(bam_tx_pipe, dma_address, len,
pkt, SPS_IOVEC_FLAG_INT | SPS_IOVEC_FLAG_EOT);
if (rc) {
DBG("%s sps_transfer_one failed rc=%d\n", __func__, rc);
DMUX_LOG_KERR("%s sps_transfer_one failed rc=%d\n",
__func__, rc);
list_del(&pkt->list_node);
DBG_INC_TX_SPS_FAILURE_CNT();
spin_unlock_irqrestore(&bam_tx_pool_spinlock, flags);
dma_unmap_single(NULL, pkt->dma_address,
pkt->len,
DMA_TO_DEVICE);
kfree(pkt);
} else {
spin_unlock_irqrestore(&bam_tx_pool_spinlock, flags);
@@ -730,10 +777,13 @@ int msm_bam_dmux_write(uint32_t id, struct sk_buff *skb)
rc = sps_transfer_one(bam_tx_pipe, dma_address, skb->len,
pkt, SPS_IOVEC_FLAG_INT | SPS_IOVEC_FLAG_EOT);
if (rc) {
DBG("%s sps_transfer_one failed rc=%d\n", __func__, rc);
DMUX_LOG_KERR("%s sps_transfer_one failed rc=%d\n",
__func__, rc);
list_del(&pkt->list_node);
DBG_INC_TX_SPS_FAILURE_CNT();
spin_unlock_irqrestore(&bam_tx_pool_spinlock, flags);
dma_unmap_single(NULL, pkt->dma_address,
pkt->skb->len, DMA_TO_DEVICE);
kfree(pkt);
if (new_skb)
dev_kfree_skb_any(new_skb);
@@ -977,7 +1027,12 @@ static void rx_switch_to_interrupt_mode(void)
info = list_first_entry(&bam_rx_pool, struct rx_pkt_info,
list_node);
list_del(&info->list_node);
--bam_rx_pool_len;
mutex_unlock(&bam_rx_pool_mutexlock);
if (info->dma_address != iov.addr)
DMUX_LOG_KERR("%s: iovec %p != dma %p\n",
__func__,
(void *)info->dma_address, (void *)iov.addr);
handle_bam_mux_cmd(&info->work);
}
return;
@@ -1016,6 +1071,7 @@ static void rx_timer_work_func(struct work_struct *work)
}
info = list_first_entry(&bam_rx_pool,
struct rx_pkt_info, list_node);
--bam_rx_pool_len;
list_del(&info->list_node);
mutex_unlock(&bam_rx_pool_mutexlock);
handle_bam_mux_cmd(&info->work);
@@ -1137,11 +1193,13 @@ static int debug_stats(char *buf, int max)
"skb copy cnt: %u\n"
"skb copy bytes: %u\n"
"sps tx failures: %u\n"
"sps tx stalls: %u\n",
"sps tx stalls: %u\n"
"rx queue len: %d\n",
bam_dmux_write_cpy_cnt,
bam_dmux_write_cpy_bytes,
bam_dmux_tx_sps_failure_cnt,
bam_dmux_tx_stall_cnt
bam_dmux_tx_stall_cnt,
bam_rx_pool_len
);
return i;
@@ -1516,8 +1574,7 @@ static void reconnect_to_bam(void)
if (polling_mode)
rx_switch_to_interrupt_mode();
for (i = 0; i < NUM_BUFFERS; ++i)
queue_rx();
queue_rx();
toggle_apps_ack();
complete_all(&bam_connection_completion);
@@ -1558,6 +1615,7 @@ static void disconnect_to_bam(void)
dev_kfree_skb_any(info->skb);
kfree(info);
}
bam_rx_pool_len = 0;
mutex_unlock(&bam_rx_pool_mutexlock);
verify_tx_queue_is_empty(__func__);
@@ -1706,7 +1764,6 @@ static int bam_init(void)
dma_addr_t dma_addr;
int ret;
void *a2_virt_addr;
int i;
int skip_iounmap = 0;
vote_dfab();
@@ -1832,8 +1889,7 @@ static int bam_init(void)
}
bam_mux_initialized = 1;
for (i = 0; i < NUM_BUFFERS; ++i)
queue_rx();
queue_rx();
toggle_apps_ack();
bam_connection_is_active = 1;
complete_all(&bam_connection_completion);