Commit 18b46810 authored Apr 08, 2016 by Alexandre TORGUE Committed by David S. Miller Apr 13, 2016

net: ethernet: stmmac: GMAC4.xx: Fix TX descriptor preparation



On GMAC4.xx each descriptor contains 2 buffers of 16KB (each).
Initially, those 2 buffers was filled in dwmac4_rd_prepare_tx_desc but
it is actually not needed. Indeed, stmmac driver supports frame up to
9000 bytes (jumbo). So only one buffer is needed.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent fbf405e8

drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c

+1 −8

Original line number	Diff line number	Diff line
		@@ -254,14 +254,7 @@ static void dwmac4_rd_prepare_tx_desc(struct dma_desc *p, int is_fs, int len,
		{
		unsigned int tdes3 = p->des3;

		if (unlikely(len > BUF_SIZE_16KiB)) {
		p->des2 \|= (((len - BUF_SIZE_16KiB) <<
		TDES2_BUFFER2_SIZE_MASK_SHIFT)
		& TDES2_BUFFER2_SIZE_MASK)
		\| (BUF_SIZE_16KiB & TDES2_BUFFER1_SIZE_MASK);
		} else {
		p->des2 \|= (len & TDES2_BUFFER1_SIZE_MASK);
		}

		if (is_fs)
		tdes3 \|= TDES3_FIRST_DESCRIPTOR;