This is a note to let you know that I've just added the patch titled

tg3: Add workaround to restrict 5762 MRRS to 2048

to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: tg3-add-workaround-to-restrict-5762-mrrs-to-2048.patch and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From foo@baz Wed Feb 28 16:19:30 CET 2018

From: Siva Reddy Kallam siva.kallam@broadcom.com Date: Fri, 22 Dec 2017 16:05:28 +0530 Subject: tg3: Add workaround to restrict 5762 MRRS to 2048

From: Siva Reddy Kallam siva.kallam@broadcom.com

[ Upstream commit 4419bb1cedcda0272e1dc410345c5a1d1da0e367 ]

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 siva.kallam@broadcom.com Signed-off-by: Michael Chan michael.chan@broadcom.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/ethernet/broadcom/tg3.c | 10 ++++++++++ drivers/net/ethernet/broadcom/tg3.h | 4 ++++ 2 files changed, 14 insertions(+)

--- a/drivers/net/ethernet/broadcom/tg3.c +++ b/drivers/net/ethernet/broadcom/tg3.c @@ -10051,6 +10051,16 @@ static int tg3_reset_hw(struct tg3 *tp,

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; --- a/drivers/net/ethernet/broadcom/tg3.h +++ b/drivers/net/ethernet/broadcom/tg3.h @@ -95,6 +95,7 @@ #define TG3PCI_SUBDEVICE_ID_DELL_JAGUAR 0x0106 #define TG3PCI_SUBDEVICE_ID_DELL_MERLOT 0x0109 #define TG3PCI_SUBDEVICE_ID_DELL_SLIM_MERLOT 0x010a +#define TG3PCI_SUBDEVICE_ID_DELL_5762 0x07f0 #define TG3PCI_SUBVENDOR_ID_COMPAQ PCI_VENDOR_ID_COMPAQ #define TG3PCI_SUBDEVICE_ID_COMPAQ_BANSHEE 0x007c #define TG3PCI_SUBDEVICE_ID_COMPAQ_BANSHEE_2 0x009a @@ -280,6 +281,9 @@ #define TG3PCI_STD_RING_PROD_IDX 0x00000098 /* 64-bit */ #define TG3PCI_RCV_RET_RING_CON_IDX 0x000000a0 /* 64-bit */ /* 0xa8 --> 0xb8 unused */ +#define TG3PCI_DEV_STATUS_CTRL 0x000000b4 +#define MAX_READ_REQ_SIZE_2048 0x00004000 +#define MAX_READ_REQ_MASK 0x00007000 #define TG3PCI_DUAL_MAC_CTRL 0x000000b8 #define DUAL_MAC_CTRL_CH_MASK 0x00000003 #define DUAL_MAC_CTRL_ID 0x00000004

Patches currently in stable-queue which might be from siva.kallam@broadcom.com are

queue-4.4/tg3-enable-phy-reset-in-mtu-change-path-for-5720.patch queue-4.4/tg3-add-workaround-to-restrict-5762-mrrs-to-2048.patch