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path: root/drivers/net/sfc/tx.c
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Diffstat (limited to 'drivers/net/sfc/tx.c')
-rw-r--r--drivers/net/sfc/tx.c83
1 files changed, 43 insertions, 40 deletions
diff --git a/drivers/net/sfc/tx.c b/drivers/net/sfc/tx.c
index 489c4de3144..303919a34df 100644
--- a/drivers/net/sfc/tx.c
+++ b/drivers/net/sfc/tx.c
@@ -26,8 +26,7 @@
* The tx_queue descriptor ring fill-level must fall below this value
* before we restart the netif queue
*/
-#define EFX_NETDEV_TX_THRESHOLD(_tx_queue) \
- (_tx_queue->efx->type->txd_ring_mask / 2u)
+#define EFX_TXQ_THRESHOLD (EFX_TXQ_MASK / 2u)
/* We want to be able to nest calls to netif_stop_queue(), since each
* channel can have an individual stop on the queue.
@@ -125,6 +124,24 @@ static void efx_tsoh_free(struct efx_tx_queue *tx_queue,
}
+static inline unsigned
+efx_max_tx_len(struct efx_nic *efx, dma_addr_t dma_addr)
+{
+ /* Depending on the NIC revision, we can use descriptor
+ * lengths up to 8K or 8K-1. However, since PCI Express
+ * devices must split read requests at 4K boundaries, there is
+ * little benefit from using descriptors that cross those
+ * boundaries and we keep things simple by not doing so.
+ */
+ unsigned len = (~dma_addr & 0xfff) + 1;
+
+ /* Work around hardware bug for unaligned buffers. */
+ if (EFX_WORKAROUND_5391(efx) && (dma_addr & 0xf))
+ len = min_t(unsigned, len, 512 - (dma_addr & 0xf));
+
+ return len;
+}
+
/*
* Add a socket buffer to a TX queue
*
@@ -147,7 +164,7 @@ static netdev_tx_t efx_enqueue_skb(struct efx_tx_queue *tx_queue,
skb_frag_t *fragment;
struct page *page;
int page_offset;
- unsigned int len, unmap_len = 0, fill_level, insert_ptr, misalign;
+ unsigned int len, unmap_len = 0, fill_level, insert_ptr;
dma_addr_t dma_addr, unmap_addr = 0;
unsigned int dma_len;
bool unmap_single;
@@ -171,7 +188,7 @@ static netdev_tx_t efx_enqueue_skb(struct efx_tx_queue *tx_queue,
}
fill_level = tx_queue->insert_count - tx_queue->old_read_count;
- q_space = efx->type->txd_ring_mask - 1 - fill_level;
+ q_space = EFX_TXQ_MASK - 1 - fill_level;
/* Map for DMA. Use pci_map_single rather than pci_map_page
* since this is more efficient on machines with sparse
@@ -208,16 +225,14 @@ static netdev_tx_t efx_enqueue_skb(struct efx_tx_queue *tx_queue,
&tx_queue->read_count;
fill_level = (tx_queue->insert_count
- tx_queue->old_read_count);
- q_space = (efx->type->txd_ring_mask - 1 -
- fill_level);
+ q_space = EFX_TXQ_MASK - 1 - fill_level;
if (unlikely(q_space-- <= 0))
goto stop;
smp_mb();
--tx_queue->stopped;
}
- insert_ptr = (tx_queue->insert_count &
- efx->type->txd_ring_mask);
+ insert_ptr = tx_queue->insert_count & EFX_TXQ_MASK;
buffer = &tx_queue->buffer[insert_ptr];
efx_tsoh_free(tx_queue, buffer);
EFX_BUG_ON_PARANOID(buffer->tsoh);
@@ -226,14 +241,10 @@ static netdev_tx_t efx_enqueue_skb(struct efx_tx_queue *tx_queue,
EFX_BUG_ON_PARANOID(!buffer->continuation);
EFX_BUG_ON_PARANOID(buffer->unmap_len);
- dma_len = (((~dma_addr) & efx->type->tx_dma_mask) + 1);
- if (likely(dma_len > len))
+ dma_len = efx_max_tx_len(efx, dma_addr);
+ if (likely(dma_len >= len))
dma_len = len;
- misalign = (unsigned)dma_addr & efx->type->bug5391_mask;
- if (misalign && dma_len + misalign > 512)
- dma_len = 512 - misalign;
-
/* Fill out per descriptor fields */
buffer->len = dma_len;
buffer->dma_addr = dma_addr;
@@ -289,7 +300,7 @@ static netdev_tx_t efx_enqueue_skb(struct efx_tx_queue *tx_queue,
/* Work backwards until we hit the original insert pointer value */
while (tx_queue->insert_count != tx_queue->write_count) {
--tx_queue->insert_count;
- insert_ptr = tx_queue->insert_count & efx->type->txd_ring_mask;
+ insert_ptr = tx_queue->insert_count & EFX_TXQ_MASK;
buffer = &tx_queue->buffer[insert_ptr];
efx_dequeue_buffer(tx_queue, buffer);
buffer->len = 0;
@@ -318,10 +329,9 @@ static void efx_dequeue_buffers(struct efx_tx_queue *tx_queue,
{
struct efx_nic *efx = tx_queue->efx;
unsigned int stop_index, read_ptr;
- unsigned int mask = tx_queue->efx->type->txd_ring_mask;
- stop_index = (index + 1) & mask;
- read_ptr = tx_queue->read_count & mask;
+ stop_index = (index + 1) & EFX_TXQ_MASK;
+ read_ptr = tx_queue->read_count & EFX_TXQ_MASK;
while (read_ptr != stop_index) {
struct efx_tx_buffer *buffer = &tx_queue->buffer[read_ptr];
@@ -338,7 +348,7 @@ static void efx_dequeue_buffers(struct efx_tx_queue *tx_queue,
buffer->len = 0;
++tx_queue->read_count;
- read_ptr = tx_queue->read_count & mask;
+ read_ptr = tx_queue->read_count & EFX_TXQ_MASK;
}
}
@@ -391,7 +401,7 @@ void efx_xmit_done(struct efx_tx_queue *tx_queue, unsigned int index)
unsigned fill_level;
struct efx_nic *efx = tx_queue->efx;
- EFX_BUG_ON_PARANOID(index > efx->type->txd_ring_mask);
+ EFX_BUG_ON_PARANOID(index > EFX_TXQ_MASK);
efx_dequeue_buffers(tx_queue, index);
@@ -401,7 +411,7 @@ void efx_xmit_done(struct efx_tx_queue *tx_queue, unsigned int index)
smp_mb();
if (unlikely(tx_queue->stopped) && likely(efx->port_enabled)) {
fill_level = tx_queue->insert_count - tx_queue->read_count;
- if (fill_level < EFX_NETDEV_TX_THRESHOLD(tx_queue)) {
+ if (fill_level < EFX_TXQ_THRESHOLD) {
EFX_BUG_ON_PARANOID(!efx_dev_registered(efx));
/* Do this under netif_tx_lock(), to avoid racing
@@ -425,11 +435,11 @@ int efx_probe_tx_queue(struct efx_tx_queue *tx_queue)
EFX_LOG(efx, "creating TX queue %d\n", tx_queue->queue);
/* Allocate software ring */
- txq_size = (efx->type->txd_ring_mask + 1) * sizeof(*tx_queue->buffer);
+ txq_size = EFX_TXQ_SIZE * sizeof(*tx_queue->buffer);
tx_queue->buffer = kzalloc(txq_size, GFP_KERNEL);
if (!tx_queue->buffer)
return -ENOMEM;
- for (i = 0; i <= efx->type->txd_ring_mask; ++i)
+ for (i = 0; i <= EFX_TXQ_MASK; ++i)
tx_queue->buffer[i].continuation = true;
/* Allocate hardware ring */
@@ -468,8 +478,7 @@ void efx_release_tx_buffers(struct efx_tx_queue *tx_queue)
/* Free any buffers left in the ring */
while (tx_queue->read_count != tx_queue->write_count) {
- buffer = &tx_queue->buffer[tx_queue->read_count &
- tx_queue->efx->type->txd_ring_mask];
+ buffer = &tx_queue->buffer[tx_queue->read_count & EFX_TXQ_MASK];
efx_dequeue_buffer(tx_queue, buffer);
buffer->continuation = true;
buffer->len = 0;
@@ -708,14 +717,14 @@ static int efx_tx_queue_insert(struct efx_tx_queue *tx_queue,
{
struct efx_tx_buffer *buffer;
struct efx_nic *efx = tx_queue->efx;
- unsigned dma_len, fill_level, insert_ptr, misalign;
+ unsigned dma_len, fill_level, insert_ptr;
int q_space;
EFX_BUG_ON_PARANOID(len <= 0);
fill_level = tx_queue->insert_count - tx_queue->old_read_count;
/* -1 as there is no way to represent all descriptors used */
- q_space = efx->type->txd_ring_mask - 1 - fill_level;
+ q_space = EFX_TXQ_MASK - 1 - fill_level;
while (1) {
if (unlikely(q_space-- <= 0)) {
@@ -731,7 +740,7 @@ static int efx_tx_queue_insert(struct efx_tx_queue *tx_queue,
*(volatile unsigned *)&tx_queue->read_count;
fill_level = (tx_queue->insert_count
- tx_queue->old_read_count);
- q_space = efx->type->txd_ring_mask - 1 - fill_level;
+ q_space = EFX_TXQ_MASK - 1 - fill_level;
if (unlikely(q_space-- <= 0)) {
*final_buffer = NULL;
return 1;
@@ -740,13 +749,13 @@ static int efx_tx_queue_insert(struct efx_tx_queue *tx_queue,
--tx_queue->stopped;
}
- insert_ptr = tx_queue->insert_count & efx->type->txd_ring_mask;
+ insert_ptr = tx_queue->insert_count & EFX_TXQ_MASK;
buffer = &tx_queue->buffer[insert_ptr];
++tx_queue->insert_count;
EFX_BUG_ON_PARANOID(tx_queue->insert_count -
tx_queue->read_count >
- efx->type->txd_ring_mask);
+ EFX_TXQ_MASK);
efx_tsoh_free(tx_queue, buffer);
EFX_BUG_ON_PARANOID(buffer->len);
@@ -757,12 +766,7 @@ static int efx_tx_queue_insert(struct efx_tx_queue *tx_queue,
buffer->dma_addr = dma_addr;
- /* Ensure we do not cross a boundary unsupported by H/W */
- dma_len = (~dma_addr & efx->type->tx_dma_mask) + 1;
-
- misalign = (unsigned)dma_addr & efx->type->bug5391_mask;
- if (misalign && dma_len + misalign > 512)
- dma_len = 512 - misalign;
+ dma_len = efx_max_tx_len(efx, dma_addr);
/* If there is enough space to send then do so */
if (dma_len >= len)
@@ -792,8 +796,7 @@ static void efx_tso_put_header(struct efx_tx_queue *tx_queue,
{
struct efx_tx_buffer *buffer;
- buffer = &tx_queue->buffer[tx_queue->insert_count &
- tx_queue->efx->type->txd_ring_mask];
+ buffer = &tx_queue->buffer[tx_queue->insert_count & EFX_TXQ_MASK];
efx_tsoh_free(tx_queue, buffer);
EFX_BUG_ON_PARANOID(buffer->len);
EFX_BUG_ON_PARANOID(buffer->unmap_len);
@@ -818,7 +821,7 @@ static void efx_enqueue_unwind(struct efx_tx_queue *tx_queue)
while (tx_queue->insert_count != tx_queue->write_count) {
--tx_queue->insert_count;
buffer = &tx_queue->buffer[tx_queue->insert_count &
- tx_queue->efx->type->txd_ring_mask];
+ EFX_TXQ_MASK];
efx_tsoh_free(tx_queue, buffer);
EFX_BUG_ON_PARANOID(buffer->skb);
buffer->len = 0;
@@ -1135,7 +1138,7 @@ static void efx_fini_tso(struct efx_tx_queue *tx_queue)
unsigned i;
if (tx_queue->buffer) {
- for (i = 0; i <= tx_queue->efx->type->txd_ring_mask; ++i)
+ for (i = 0; i <= EFX_TXQ_MASK; ++i)
efx_tsoh_free(tx_queue, &tx_queue->buffer[i]);
}