sfc: Replace some literal constants with EFX_PAGE_SIZE/EFX_BUF_SIZE
The 'page size' for PCIe DMA, i.e. the alignment of boundaries at
which DMA must be broken, is 4KB. Name this value as EFX_PAGE_SIZE
and use it in efx_max_tx_len(). Redefine EFX_BUF_SIZE as
EFX_PAGE_SIZE since its value is also a result of that requirement,
and use it in efx_init_special_buffer().
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
diff --git a/drivers/net/ethernet/sfc/nic.c b/drivers/net/ethernet/sfc/nic.c
index a43d1ca..dd50c4f 100644
--- a/drivers/net/ethernet/sfc/nic.c
+++ b/drivers/net/ethernet/sfc/nic.c
@@ -54,9 +54,6 @@
#define EFX_FLUSH_INTERVAL 10
#define EFX_FLUSH_POLL_COUNT 100
-/* Size and alignment of special buffers (4KB) */
-#define EFX_BUF_SIZE 4096
-
/* Depth of RX flush request fifo */
#define EFX_RX_FLUSH_COUNT 4
@@ -196,7 +193,7 @@
/* Write buffer descriptors to NIC */
for (i = 0; i < buffer->entries; i++) {
index = buffer->index + i;
- dma_addr = buffer->dma_addr + (i * 4096);
+ dma_addr = buffer->dma_addr + (i * EFX_BUF_SIZE);
netif_dbg(efx, probe, efx->net_dev,
"mapping special buffer %d at %llx\n",
index, (unsigned long long)dma_addr);