[32/88] net: sh_eth: fix incorrect RX length error if R8A7740

Steven Rostedt
2013-08-13T16:04:22Z

[-- Attachment #1: 0032-net-sh_eth-fix-incorrect-RX-length-error-if-R8A7740.patch --]
[-- Type: text/plain, Size: 1777 bytes --]

3.6.11.7-rc1 stable review patch.
If anyone has any objections, please let me know.

------------------

From: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>

[ Upstream commit dd019897358b815f7828dab90b51d51df4d3658d ]

This patch fixes an issue that the driver increments the "RX length error"
on every buffer in sh_eth_rx() if the R8A7740.
This patch also adds a description about the Receive Frame Status bits.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
drivers/net/ethernet/renesas/sh_eth.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/renesas/sh_eth.c b/drivers/net/ethernet/renesas/sh_eth.c
index bad8f2e..cce72da 100644
--- a/drivers/net/ethernet/renesas/sh_eth.c
+++ b/drivers/net/ethernet/renesas/sh_eth.c
@@ -1102,16 +1102,23 @@ static int sh_eth_rx(struct net_device *ndev, u32 intr_status)
desc_status = edmac_to_cpu(mdp, rxdesc->status);
pkt_len = rxdesc->frame_length;

-#if defined(CONFIG_ARCH_R8A7740)
- desc_status >>= 16;
-#endif
-
if (--boguscnt < 0)
break;

if (!(desc_status & RDFEND))
ndev->stats.rx_length_errors++;

+#if defined(CONFIG_ARCH_R8A7740)
+ /*
+ * In case of almost all GETHER/ETHERs, the Receive Frame State
+ * (RFS) bits in the Receive Descriptor 0 are from bit 9 to
+ * bit 0. However, in case of the R8A7740's GETHER, the RFS
+ * bits are from bit 25 to bit 16. So, the driver needs right
+ * shifting by 16.
+ */
+ desc_status >>= 16;
+#endif
+
if (desc_status & (RD_RFS1 | RD_RFS2 | RD_RFS3 | RD_RFS4 |
RD_RFS5 | RD_RFS6 | RD_RFS10)) {
ndev->stats.rx_errors++;
--
1.7.10.4