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From:   Wu Zongyong <wuzongyong@linux.alibaba.com>
To:     sdonthineni@nvidia.com, bhelgaas@google.com,
        linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org
Cc:     Wu Zongyong <wuzongyong@linux.alibaba.com>,
        wllenyj@linux.alibaba.com, wutu.xq2@linux.alibaba.com,
        gerry@linux.alibaba.com
Subject: [RFC PATCH] PCI: avoid SBR for NVIDIA T4
Date:   Wed, 29 Mar 2023 19:58:45 +0800
Message-Id: <388bc353a5f88edb502ec04c0dc53ab62a526020.1680090885.git.wuzongyong@linux.alibaba.com>
MIME-Version: 1.0
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Secondary bus reset will fail if NVIDIA T4 card is direct attached to a
root port.
So avoid to do bus reset,  pci_parent_bus_reset() works nomarlly.

Maybe NVIDIA guys can do some detailed explanation abount the SBR
behaviour of GPUs.

Signed-off-by: Wu Zongyong <wuzongyong@linux.alibaba.com>
---
 drivers/pci/quirks.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 44cab813bf95..be86b93b9e38 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -3618,7 +3618,7 @@ static void quirk_no_bus_reset(struct pci_dev *dev)
  */
 static void quirk_nvidia_no_bus_reset(struct pci_dev *dev)
 {
-	if ((dev->device & 0xffc0) == 0x2340)
+	if ((dev->device & 0xffc0) == 0x2340 || dev->device == 0x1eb8)
 		quirk_no_bus_reset(dev);
 }
 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_NVIDIA, PCI_ANY_ID,
-- 
2.34.3