From 907830b0fc9e374d00f3c83de5e426157b482c01 Mon Sep 17 00:00:00 2001
From: Nirmoy Das <nirmoy.das@amd.com>
Date: Thu, 7 Jan 2021 12:26:55 +0100
Subject: [PATCH] PCI: Add a REBAR size quirk for Sapphire RX 5600 XT Pulse
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RX 5600 XT Pulse advertises support for BAR 0 being 256MB, 512MB,
or 1GB, but it also supports 2GB, 4GB, and 8GB. Add a rebar
size quirk so that the BAR 0 is big enough to cover complete VARM.

Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Nirmoy Das <nirmoy.das@amd.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20210107175017.15893-5-nirmoy.das@amd.com
---
 drivers/pci/pci.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 99ef2774b9d05..09b03cfba8894 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -3603,7 +3603,14 @@ u32 pci_rebar_get_possible_sizes(struct pci_dev *pdev, int bar)
 		return 0;
 
 	pci_read_config_dword(pdev, pos + PCI_REBAR_CAP, &cap);
-	return (cap & PCI_REBAR_CAP_SIZES) >> 4;
+	cap &= PCI_REBAR_CAP_SIZES;
+
+	/* Sapphire RX 5600 XT Pulse has an invalid cap dword for BAR 0 */
+	if (pdev->vendor == PCI_VENDOR_ID_ATI && pdev->device == 0x731f &&
+	    bar == 0 && cap == 0x7000)
+		cap = 0x3f000;
+
+	return cap >> 4;
 }
 EXPORT_SYMBOL(pci_rebar_get_possible_sizes);
 
-- 
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