On Thu, May 17, 2018 at 09:22:23AM -0400, Sinan Kaya wrote:

A host bridge is allowed to remap BAR addresses using _TRA attribute in _CRS windows.

pci_bus 0000:00: root bus resource [mem 0x80100100000-0x8011fffffff window] (bus address [0x00100000-0x1fffffff]) pci 0000:02:00.0: reg 0x10: [mem 0x8011e000000-0x8011effffff]

When a VGA device is behind such a host bridge and the resource is translated efifb driver is trying to do ioremap against bus address rather than the resource address and is failing to probe.

efifb driver is having difficulty locating the base address from BAR address when

efifb: probing for efifb efifb: cannot reserve video memory at 0x1e000000 efifb: framebuffer at 0x1e000000, using 1920k, total 1875k efifb: mode is 800x600x32, linelength=3200, pages=1 efifb: scrolling: redraw efifb: Truecolor: size=8:8:8:8, shift=24:16:8:0

Use the host bridge offset information to convert bus address to resource address in the fixup.

Signed-off-by: Sinan Kaya okaya@codeaurora.org

Looks reasonable to me - Ard, do you want to take this up through the EFI tree?

Signed-off-by: Peter Jones pjones@redhat.com

---

drivers/video/fbdev/efifb.c | 10 ++++++++++ 1 file changed, 10 insertions(+)

diff --git a/drivers/video/fbdev/efifb.c b/drivers/video/fbdev/efifb.c index 46a4484..ea68d5c 100644 --- a/drivers/video/fbdev/efifb.c +++ b/drivers/video/fbdev/efifb.c @@ -428,6 +428,8 @@ static void efifb_fixup_resources(struct pci_dev *dev) { u64 base = screen_info.lfb_base; u64 size = screen_info.lfb_size;

• struct pci_bus_region region;

• struct resource res; int i;

  if (efifb_pci_dev || screen_info.orig_video_isVGA != VIDEO_TYPE_EFI)

@@ -439,6 +441,14 @@ static void efifb_fixup_resources(struct pci_dev *dev) if (!base) return;

• region.start = base;
• region.end = base + size - 1;
• res.start = 0;
• res.flags = IORESOURCE_MEM;
• pcibios_bus_to_resource(dev->bus, &res, &region);
• if (res.start)

• base = res.start;
  

• for (i = 0; i <= PCI_STD_RESOURCE_END; i++) { struct resource *res = &dev->resource[i];

-- 2.7.4

On 17/05/18 14:22, Sinan Kaya wrote:

A host bridge is allowed to remap BAR addresses using _TRA attribute in _CRS windows.

pci_bus 0000:00: root bus resource [mem 0x80100100000-0x8011fffffff window] (bus address [0x00100000-0x1fffffff]) pci 0000:02:00.0: reg 0x10: [mem 0x8011e000000-0x8011effffff]

When a VGA device is behind such a host bridge and the resource is translated efifb driver is trying to do ioremap against bus address rather than the resource address and is failing to probe.

efifb driver is having difficulty locating the base address from BAR address when

efifb: probing for efifb efifb: cannot reserve video memory at 0x1e000000 efifb: framebuffer at 0x1e000000, using 1920k, total 1875k efifb: mode is 800x600x32, linelength=3200, pages=1 efifb: scrolling: redraw efifb: Truecolor: size=8:8:8:8, shift=24:16:8:0

Use the host bridge offset information to convert bus address to resource address in the fixup.

Signed-off-by: Sinan Kaya okaya@codeaurora.org

drivers/video/fbdev/efifb.c | 10 ++++++++++ 1 file changed, 10 insertions(+)

diff --git a/drivers/video/fbdev/efifb.c b/drivers/video/fbdev/efifb.c index 46a4484..ea68d5c 100644 --- a/drivers/video/fbdev/efifb.c +++ b/drivers/video/fbdev/efifb.c @@ -428,6 +428,8 @@ static void efifb_fixup_resources(struct pci_dev *dev) { u64 base = screen_info.lfb_base; u64 size = screen_info.lfb_size;

FWIW, now that I've actually gone and looked, it appears you could simplify the whole function quite a bit by getting rid of these and just using the new local resource directly, especially since the only actual use of size is an open-coded resource_contains().

• struct pci_bus_region region;

• struct resource res; int i;

  if (efifb_pci_dev || screen_info.orig_video_isVGA != VIDEO_TYPE_EFI)

@@ -439,6 +441,14 @@ static void efifb_fixup_resources(struct pci_dev *dev) if (!base) return;

• region.start = base;
• region.end = base + size - 1;
• res.start = 0;
• res.flags = IORESOURCE_MEM;
• pcibios_bus_to_resource(dev->bus, &res, &region);
• if (res.start)

• base = res.start;
  

• for (i = 0; i <= PCI_STD_RESOURCE_END; i++) { struct resource *res = &dev->resource[i];

The inadvertent name shadowing here is a bit yuck, though, and I think sparse will whinge about it, so it's probably worth renaming one or the other.

Robin.