[PATCH 5/8] pci: allow for overriding the list of advertised BAR sizes

[Darren Salt]

This is intended for devices which are known to work with BAR sizes other
than those which they advertise; usually larger.
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 2 +-
 drivers/pci/setup-res.c                    | 4 ++--
 include/linux/pci.h                        | 2 +-
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index c6495a86b280..ce3b8f8fea0c 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -995,7 +995,7 @@ int amdgpu_device_resize_fb_bar(struct amdgpu_device *adev)
 	     rbar_size >= 0;
 	     rbar_size = fls(available_sizes & ~(-1 << rbar_size)) - 1
 	    ) {
-		r = pci_resize_resource(adev->pdev, 0, rbar_size);
+		r = pci_resize_resource(adev->pdev, 0, rbar_size, false);
 		if (r == 0) {
 			break;
 		} else if (r == -ENOTSUPP) {
diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c
index 43eda101fcf4..3651754de433 100644
--- a/drivers/pci/setup-res.c
+++ b/drivers/pci/setup-res.c
@@ -407,7 +407,7 @@ void pci_release_resource(struct pci_dev *dev, int resno)
 }
 EXPORT_SYMBOL(pci_release_resource);
 
-int pci_resize_resource(struct pci_dev *dev, int resno, int size)
+int pci_resize_resource(struct pci_dev *dev, int resno, int size, bool forced)
 {
 	struct resource *res = dev->resource + resno;
 	int old, ret;
@@ -426,7 +426,7 @@ int pci_resize_resource(struct pci_dev *dev, int resno, int size)
 	if (!sizes)
 		return -ENOTSUPP;
 
-	if (!(sizes & BIT(size)))
+	if (!forced && !(sizes & BIT(size)))
 		return -EINVAL;
 
 	old = pci_rebar_get_current_size(dev, resno);
diff --git a/include/linux/pci.h b/include/linux/pci.h
index dca2778c1738..c7d687370562 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1234,7 +1234,7 @@ static __always_inline u64 pci_rebar_size_to_bytes(int size)
 	return 1ULL << (size + 20);
 }
 u32 pci_rebar_get_possible_sizes(struct pci_dev *pdev, int bar);
-int __must_check pci_resize_resource(struct pci_dev *dev, int i, int size);
+int __must_check pci_resize_resource(struct pci_dev *dev, int i, int size, bool forced);
 int pci_select_bars(struct pci_dev *dev, unsigned long flags);
 bool pci_device_is_present(struct pci_dev *pdev);
 void pci_ignore_hotplug(struct pci_dev *dev);
-- 
2.20.1