From 4419bb1cedcda0272e1dc410345c5a1d1da0e367 Mon Sep 17 00:00:00 2001 From: Siva Reddy Kallam Date: Fri, 22 Dec 2017 16:05:28 +0530 Subject: tg3: Add workaround to restrict 5762 MRRS to 2048 One of AMD based server with 5762 hangs with jumbo frame traffic. This AMD platform has southbridge limitation which is restricting MRRS to 4000. As a work around, driver to restricts the MRRS to 2048 for this particular 5762 NX1 card. Signed-off-by: Siva Reddy Kallam Signed-off-by: Michael Chan Signed-off-by: David S. Miller --- drivers/net/ethernet/broadcom/tg3.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'drivers/net/ethernet/broadcom/tg3.c') diff --git a/drivers/net/ethernet/broadcom/tg3.c b/drivers/net/ethernet/broadcom/tg3.c index 5fe8d9b05f31..a0caa71a8c3b 100644 --- a/drivers/net/ethernet/broadcom/tg3.c +++ b/drivers/net/ethernet/broadcom/tg3.c @@ -10054,6 +10054,16 @@ static int tg3_reset_hw(struct tg3 *tp, bool reset_phy) tw32(GRC_MODE, tp->grc_mode | val); + /* On one of the AMD platform, MRRS is restricted to 4000 because of + * south bridge limitation. As a workaround, Driver is setting MRRS + * to 2048 instead of default 4096. + */ + if (tp->pdev->subsystem_vendor == PCI_VENDOR_ID_DELL && + tp->pdev->subsystem_device == TG3PCI_SUBDEVICE_ID_DELL_5762) { + val = tr32(TG3PCI_DEV_STATUS_CTRL) & ~MAX_READ_REQ_MASK; + tw32(TG3PCI_DEV_STATUS_CTRL, val | MAX_READ_REQ_SIZE_2048); + } + /* Setup the timer prescalar register. Clock is always 66Mhz. */ val = tr32(GRC_MISC_CFG); val &= ~0xff; -- cgit v1.2.3-59-g8ed1b