From b39fe41f481d20c201012e4483e76c203802dda7 Mon Sep 17 00:00:00 2001 From: Francois Romieu Date: Mon, 11 Sep 2006 20:10:58 +0200 Subject: [PATCH] r8169: quirk for the 8110sb on arm platform Inverting the write ordering of the TxDescAddr{High/Low} registers suffices to trigger a sabbat of PCI errors which make the device completely dysfunctional. The issue has not been reported on a different platform. Switching from MMIO accesses to I/O ones as done in Realtek's own driver fixes (papers over ?) the bug as well but I am not thrilled to see everyone pay the I/O price for an obscure bug. This is the minimal change to handle the issue. Signed-off-by: Francois Romieu Reported-by: Lennert Buytenhek --- drivers/net/r8169.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/net/r8169.c b/drivers/net/r8169.c index 93228c518ae7..805562b8624e 100644 --- a/drivers/net/r8169.c +++ b/drivers/net/r8169.c @@ -1904,10 +1904,15 @@ rtl8169_hw_start(struct net_device *dev) */ RTL_W16(IntrMitigate, 0x0000); - RTL_W32(TxDescStartAddrLow, ((u64) tp->TxPhyAddr & DMA_32BIT_MASK)); + /* + * Magic spell: some iop3xx ARM board needs the TxDescAddrHigh + * register to be written before TxDescAddrLow to work. + * Switching from MMIO to I/O access fixes the issue as well. + */ RTL_W32(TxDescStartAddrHigh, ((u64) tp->TxPhyAddr >> 32)); - RTL_W32(RxDescAddrLow, ((u64) tp->RxPhyAddr & DMA_32BIT_MASK)); + RTL_W32(TxDescStartAddrLow, ((u64) tp->TxPhyAddr & DMA_32BIT_MASK)); RTL_W32(RxDescAddrHigh, ((u64) tp->RxPhyAddr >> 32)); + RTL_W32(RxDescAddrLow, ((u64) tp->RxPhyAddr & DMA_32BIT_MASK)); RTL_W8(ChipCmd, CmdTxEnb | CmdRxEnb); RTL_W8(Cfg9346, Cfg9346_Lock); -- 2.20.1