Subject: [PATCH] r8169: fix invalid register dump

From: Peter Wu <[email-masked]>
Date: Tue, 13 Aug 2013 22:37:45 +0200

From: Peter Wu <[email-masked]>

For some reason, my PCIe RTL8111E onboard NIC on a GA-Z68X-UD3H-B3
motherboard reads as FFs when reading from MMIO with a block size
larger than 7. Therefore change to reading blocks of four bytes.

Signed-off-by: Peter Wu <[email-masked]>
---
Hi,

Personally I dislike the repetition of this patch, a hypothetical
`memcpy_fromio_block(bytes, tp->mmio_addr, 4)` would look cleaner, but
perhaps I am doing something wrong because apparantly nobody had a need
for reading multiple blocks from IO?

Anyway, this patch (with patched ethtool) allows `ethtool -d` to be more
useful for the mentioned chip.

Regards,
Peter
---
 drivers/net/ethernet/realtek/r8169.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/realtek/r8169.c b/drivers/net/ethernet/realtek/r8169.c
index b5eb419..28af01c 100644
--- a/drivers/net/ethernet/realtek/r8169.c
+++ b/drivers/net/ethernet/realtek/r8169.c
@@ -1897,12 +1897,17 @@ static void rtl8169_get_regs(struct net_device *dev, struct ethtool_regs *regs,
 			     void *p)
 {
 	struct rtl8169_private *tp = netdev_priv(dev);
+	char *bytes = p;
+	int i;
 
 	if (regs->len > R8169_REGS_SIZE)
 		regs->len = R8169_REGS_SIZE;
 
 	rtl_lock_work(tp);
-	memcpy_fromio(p, tp->mmio_addr, regs->len);
+	for (i = 0; i < regs->len - 4; i += 4)
+		memcpy_fromio(bytes + i, tp->mmio_addr + i, 4);
+	if (i < regs->len)
+		memcpy_fromio(bytes + i, tp->mmio_addr + i, regs->len - i);
 	rtl_unlock_work(tp);
 }
 
-- 
1.8.3.4