[PATCH V2 1/2] efi/fb: Simplify fixup code to prefer struct resource

[PATCH V2 1/2] efi/fb: Simplify fixup code to prefer struct resource

[Sinan Kaya]

Get rid of base and size variables in favor of a struct resource.
The conditional for checking window can be replaced with
resource_contains().

Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
---
 drivers/video/fbdev/efifb.c | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/drivers/video/fbdev/efifb.c b/drivers/video/fbdev/efifb.c
index 46a4484..6daac8d 100644
--- a/drivers/video/fbdev/efifb.c
+++ b/drivers/video/fbdev/efifb.c
@@ -426,17 +426,20 @@ static void record_efifb_bar_resource(struct pci_dev *dev, int idx, u64 offset)
 
 static void efifb_fixup_resources(struct pci_dev *dev)
 {
-	u64 base = screen_info.lfb_base;
-	u64 size = screen_info.lfb_size;
+	struct resource screen_res = {
+		.start = screen_info.lfb_base,
+		.end = screen_info.lfb_base + screen_info.lfb_size - 1,
+		.flags = IORESOURCE_MEM,
+	};
 	int i;
 
 	if (efifb_pci_dev || screen_info.orig_video_isVGA != VIDEO_TYPE_EFI)
 		return;
 
 	if (screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE)
-		base |= (u64)screen_info.ext_lfb_base << 32;
+		screen_res.start |= (u64)screen_info.ext_lfb_base << 32;
 
-	if (!base)
+	if (!screen_res.start)
 		return;
 
 	for (i = 0; i <= PCI_STD_RESOURCE_END; i++) {
@@ -445,8 +448,10 @@ static void efifb_fixup_resources(struct pci_dev *dev)
 		if (!(res->flags & IORESOURCE_MEM))
 			continue;
 
-		if (res->start <= base && res->end >= base + size - 1) {
-			record_efifb_bar_resource(dev, i, base - res->start);
+		if (resource_contains(res, &screen_res)) {
+			u64 win_offset =  screen_res.start - res->start;
+
+			record_efifb_bar_resource(dev, i, win_offset);
 			break;
 		}
 	}
-- 
2.7.4

[PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[Sinan Kaya]

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: 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 | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/video/fbdev/efifb.c b/drivers/video/fbdev/efifb.c
index 6daac8d..429cc85 100644
--- a/drivers/video/fbdev/efifb.c
+++ b/drivers/video/fbdev/efifb.c
@@ -431,6 +431,7 @@ static void efifb_fixup_resources(struct pci_dev *dev)
 		.end = screen_info.lfb_base + screen_info.lfb_size - 1,
 		.flags = IORESOURCE_MEM,
 	};
+	struct pci_bus_region region;
 	int i;
 
 	if (efifb_pci_dev || screen_info.orig_video_isVGA != VIDEO_TYPE_EFI)
@@ -442,6 +443,10 @@ static void efifb_fixup_resources(struct pci_dev *dev)
 	if (!screen_res.start)
 		return;
 
+	region.start = screen_res.start;
+	region.end = screen_res.end;
+	pcibios_bus_to_resource(dev->bus, &screen_res, &region);
+
 	for (i = 0; i <= PCI_STD_RESOURCE_END; i++) {
 		struct resource *res = &dev->resource[i];
 
-- 
2.7.4

Re: [PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[Sinan Kaya]

Hi Ard,

On 5/18/2018 10:17 AM, 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: 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>
> ---

I didn't see any messages about these getting picked up for 4.18.

Are they queued on your own branch?

Sinan

-- 
Sinan Kaya
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.

Re: [PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[Ard Biesheuvel]

On 13 June 2018 at 16:22, Sinan Kaya <okaya@codeaurora.org> wrote:
> Hi Ard,
>
> On 5/18/2018 10:17 AM, 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: 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>
>> ---
>
> I didn't see any messages about these getting picked up for 4.18.
>
> Are they queued on your own branch?
>

No, you never cc'ed me on them until now.

Re: [PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[okaya]

On 2018-06-13 11:06, Ard Biesheuvel wrote:
> On 13 June 2018 at 16:22, Sinan Kaya <okaya@codeaurora.org> wrote:
>> Hi Ard,
>> 
>> On 5/18/2018 10:17 AM, 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: 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>
>>> ---
>> 
>> I didn't see any messages about these getting picked up for 4.18.
>> 
>> Are they queued on your own branch?
>> 
> 
> No, you never cc'ed me on them until now.

Ouch, I hoped that you would get it via get_maintainer script. Sorry for 
that.

Re: [PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[Ard Biesheuvel]

On 13 June 2018 at 17:17,  <okaya@codeaurora.org> wrote:
> On 2018-06-13 11:06, Ard Biesheuvel wrote:
>>
>> On 13 June 2018 at 16:22, Sinan Kaya <okaya@codeaurora.org> wrote:
>>>
>>> Hi Ard,
>>>
>>> On 5/18/2018 10:17 AM, 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: 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>
>>>> ---
>>>
>>>
>>> I didn't see any messages about these getting picked up for 4.18.
>>>
>>> Are they queued on your own branch?
>>>
>>
>> No, you never cc'ed me on them until now.
>
>
> Ouch, I hoped that you would get it via get_maintainer script. Sorry for
> that.

Actually, get_maintainer is right: this should go through the fbdev
tree not the EFI tree

Were you going to resend them? If not, I can find them in my archive
and ack them, and we will ask Bartlomiej to take them for v4.19

Re: [PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[okaya]

On 2018-06-13 11:22, Ard Biesheuvel wrote:
> On 13 June 2018 at 17:17,  <okaya@codeaurora.org> wrote:
>> On 2018-06-13 11:06, Ard Biesheuvel wrote:
>>> 
>>> On 13 June 2018 at 16:22, Sinan Kaya <okaya@codeaurora.org> wrote:
>>>> 
>>>> Hi Ard,
>>>> 
>>>> On 5/18/2018 10:17 AM, 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: 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>
>>>>> ---
>>>> 
>>>> 
>>>> I didn't see any messages about these getting picked up for 4.18.
>>>> 
>>>> Are they queued on your own branch?
>>>> 
>>> 
>>> No, you never cc'ed me on them until now.
>> 
>> 
>> Ouch, I hoped that you would get it via get_maintainer script. Sorry 
>> for
>> that.
> 
> Actually, get_maintainer is right: this should go through the fbdev
> tree not the EFI tree
> 
> Were you going to resend them? If not, I can find them in my archive
> and ack them, and we will ask Bartlomiej to take them for v4.19

I prefer ack rather than resend to be honest.

Re: [PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[Ard Biesheuvel]

On 18 May 2018 at 16:17, Sinan Kaya <okaya@codeaurora.org> 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: 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>

Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

Bartlomiej, could you please take these via the fbdev tree for v4.19?
Peter already gave his ack but Sinan dropped it (presumably because of
the split in v2)

Sinan, does this need to go to -stable? I.e., has it ever worked before?



> ---
>  drivers/video/fbdev/efifb.c | 5 +++++
>  1 file changed, 5 insertions(+)
>
> diff --git a/drivers/video/fbdev/efifb.c b/drivers/video/fbdev/efifb.c
> index 6daac8d..429cc85 100644
> --- a/drivers/video/fbdev/efifb.c
> +++ b/drivers/video/fbdev/efifb.c
> @@ -431,6 +431,7 @@ static void efifb_fixup_resources(struct pci_dev *dev)
>                 .end = screen_info.lfb_base + screen_info.lfb_size - 1,
>                 .flags = IORESOURCE_MEM,
>         };
> +       struct pci_bus_region region;
>         int i;
>
>         if (efifb_pci_dev || screen_info.orig_video_isVGA != VIDEO_TYPE_EFI)
> @@ -442,6 +443,10 @@ static void efifb_fixup_resources(struct pci_dev *dev)
>         if (!screen_res.start)
>                 return;
>
> +       region.start = screen_res.start;
> +       region.end = screen_res.end;
> +       pcibios_bus_to_resource(dev->bus, &screen_res, &region);
> +
>         for (i = 0; i <= PCI_STD_RESOURCE_END; i++) {
>                 struct resource *res = &dev->resource[i];
>
> --
> 2.7.4
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[okaya]

On 2018-06-13 11:45, Ard Biesheuvel wrote:
> On 18 May 2018 at 16:17, Sinan Kaya <okaya@codeaurora.org> 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: 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>
> 
> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> 
> Bartlomiej, could you please take these via the fbdev tree for v4.19?
> Peter already gave his ack but Sinan dropped it (presumably because of
> the split in v2)
> 
> Sinan, does this need to go to -stable? I.e., has it ever worked 
> before?
> 

Yes, it needs to go to stable. It never worked before. Issue was found 
during a graphics bring up with AST driver.

It needs a 32 bit graphics card and a 32 bit translating host bridge to 
hit the issue.

> 
> 
>> ---
>>  drivers/video/fbdev/efifb.c | 5 +++++
>>  1 file changed, 5 insertions(+)
>> 
>> diff --git a/drivers/video/fbdev/efifb.c b/drivers/video/fbdev/efifb.c
>> index 6daac8d..429cc85 100644
>> --- a/drivers/video/fbdev/efifb.c
>> +++ b/drivers/video/fbdev/efifb.c
>> @@ -431,6 +431,7 @@ static void efifb_fixup_resources(struct pci_dev 
>> *dev)
>>                 .end = screen_info.lfb_base + screen_info.lfb_size - 
>> 1,
>>                 .flags = IORESOURCE_MEM,
>>         };
>> +       struct pci_bus_region region;
>>         int i;
>> 
>>         if (efifb_pci_dev || screen_info.orig_video_isVGA != 
>> VIDEO_TYPE_EFI)
>> @@ -442,6 +443,10 @@ static void efifb_fixup_resources(struct pci_dev 
>> *dev)
>>         if (!screen_res.start)
>>                 return;
>> 
>> +       region.start = screen_res.start;
>> +       region.end = screen_res.end;
>> +       pcibios_bus_to_resource(dev->bus, &screen_res, &region);
>> +
>>         for (i = 0; i <= PCI_STD_RESOURCE_END; i++) {
>>                 struct resource *res = &dev->resource[i];
>> 
>> --
>> 2.7.4
>> 
>> 
>> _______________________________________________
>> linux-arm-kernel mailing list
>> linux-arm-kernel@lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[Bartlomiej Zolnierkiewicz]

On Wednesday, June 13, 2018 05:45:48 PM Ard Biesheuvel wrote:
> On 18 May 2018 at 16:17, Sinan Kaya <okaya@codeaurora.org> 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: 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>
> 
> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> 
> Bartlomiej, could you please take these via the fbdev tree for v4.19?

Sure, I will queue it after the current merge window.

> Peter already gave his ack but Sinan dropped it (presumably because of
> the split in v2)

Peter, can I (re)add your ACK to V2 patches?

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

Re: [PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[Ard Biesheuvel]

On 13 June 2018 at 18:08, Bartlomiej Zolnierkiewicz
<b.zolnierkie@samsung.com> wrote:
> On Wednesday, June 13, 2018 05:45:48 PM Ard Biesheuvel wrote:
>> On 18 May 2018 at 16:17, Sinan Kaya <okaya@codeaurora.org> 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: 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>
>>
>> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
>>
>> Bartlomiej, could you please take these via the fbdev tree for v4.19?
>
> Sure, I will queue it after the current merge window.
>
>> Peter already gave his ack but Sinan dropped it (presumably because of
>> the split in v2)
>
> Peter, can I (re)add your ACK to V2 patches?
>

Actually, it would be better if we could take this through the EFI
tree instead, with your ack. Would you mind?

There are some other efifb changes coming up, some of which depend on
core EFI changes, and taking these through different trees is going to
be more trouble than it's worth.

https://marc.info/?l=linux-efi&m=152929425329015&w=2 from Hans, and the series

[PATCH v2 0/2] efi: add support for cacheable efifb mappings

that I just cc'ed you on a minute ago.

Thanks.

Re: [PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[Bartlomiej Zolnierkiewicz]

On Friday, June 22, 2018 09:54:22 AM Ard Biesheuvel wrote:
> On 13 June 2018 at 18:08, Bartlomiej Zolnierkiewicz
> <b.zolnierkie@samsung.com> wrote:
> > On Wednesday, June 13, 2018 05:45:48 PM Ard Biesheuvel wrote:
> >> On 18 May 2018 at 16:17, Sinan Kaya <okaya@codeaurora.org> 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: 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>
> >>
> >> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> >>
> >> Bartlomiej, could you please take these via the fbdev tree for v4.19?
> >
> > Sure, I will queue it after the current merge window.
> >
> >> Peter already gave his ack but Sinan dropped it (presumably because of
> >> the split in v2)
> >
> > Peter, can I (re)add your ACK to V2 patches?
> >
> 
> Actually, it would be better if we could take this through the EFI
> tree instead, with your ack. Would you mind?

Fine with me.

> There are some other efifb changes coming up, some of which depend on
> core EFI changes, and taking these through different trees is going to
> be more trouble than it's worth.

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

Re: [PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[Bartlomiej Zolnierkiewicz]

On Friday, June 22, 2018 12:07:48 PM Bartlomiej Zolnierkiewicz wrote:
> On Friday, June 22, 2018 09:54:22 AM Ard Biesheuvel wrote:
> > On 13 June 2018 at 18:08, Bartlomiej Zolnierkiewicz
> > <b.zolnierkie@samsung.com> wrote:
> > > On Wednesday, June 13, 2018 05:45:48 PM Ard Biesheuvel wrote:
> > >> On 18 May 2018 at 16:17, Sinan Kaya <okaya@codeaurora.org> 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: 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>
> > >>
> > >> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> > >>
> > >> Bartlomiej, could you please take these via the fbdev tree for v4.19?
> > >
> > > Sure, I will queue it after the current merge window.
> > >
> > >> Peter already gave his ack but Sinan dropped it (presumably because of
> > >> the split in v2)
> > >
> > > Peter, can I (re)add your ACK to V2 patches?
> > >
> > 
> > Actually, it would be better if we could take this through the EFI
> > tree instead, with your ack. Would you mind?
> 
> Fine with me.

Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

Re: [PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[Bjorn Helgaas]

Minor subject nit: From the caller's point of view, we must convert a bus
address to a resource *always* (the caller has no knowledge of "whether it
is translated by the host bridge").

On Fri, May 18, 2018 at 10:17:51AM -0400, Sinan Kaya wrote:
> A host bridge is allowed to remap BAR addresses using _TRA attribute in
> _CRS windows.

Also, _TRA/_CRS are ACPI-specific terms and non-ACPI host bridges can
also do the same sort of translation.  Another trivial nit.

> 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: 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>

Reviewed-by: Bjorn Helgaas <bhelgaas@google.com>

Thanks a lot for fixing this!

> ---
>  drivers/video/fbdev/efifb.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/video/fbdev/efifb.c b/drivers/video/fbdev/efifb.c
> index 6daac8d..429cc85 100644
> --- a/drivers/video/fbdev/efifb.c
> +++ b/drivers/video/fbdev/efifb.c
> @@ -431,6 +431,7 @@ static void efifb_fixup_resources(struct pci_dev *dev)
>  		.end = screen_info.lfb_base + screen_info.lfb_size - 1,
>  		.flags = IORESOURCE_MEM,
>  	};
> +	struct pci_bus_region region;
>  	int i;
>  
>  	if (efifb_pci_dev || screen_info.orig_video_isVGA != VIDEO_TYPE_EFI)
> @@ -442,6 +443,10 @@ static void efifb_fixup_resources(struct pci_dev *dev)
>  	if (!screen_res.start)
>  		return;
>  
> +	region.start = screen_res.start;
> +	region.end = screen_res.end;
> +	pcibios_bus_to_resource(dev->bus, &screen_res, &region);
> +
>  	for (i = 0; i <= PCI_STD_RESOURCE_END; i++) {
>  		struct resource *res = &dev->resource[i];
>  
> -- 
> 2.7.4
> 
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[Ard Biesheuvel]

On 20 June 2018 at 00:29, Bjorn Helgaas <helgaas@kernel.org> wrote:
> Minor subject nit: From the caller's point of view, we must convert a bus
> address to a resource *always* (the caller has no knowledge of "whether it
> is translated by the host bridge").
>
> On Fri, May 18, 2018 at 10:17:51AM -0400, Sinan Kaya wrote:
>> A host bridge is allowed to remap BAR addresses using _TRA attribute in
>> _CRS windows.
>
> Also, _TRA/_CRS are ACPI-specific terms and non-ACPI host bridges can
> also do the same sort of translation.  Another trivial nit.
>
>> 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: 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>
>
> Reviewed-by: Bjorn Helgaas <bhelgaas@google.com>
>
> Thanks a lot for fixing this!
>

Apologies for only bringing this up now, but I think this patch is
wrong after all.

screen_info.lfb_base is supposed to be a CPU address, and so
translating it like this is wrong. If you end up with a PCI address
here, you have made a mistake in hacking support for PCI outbound
translations into UEFI. Other users such as UEFI itself or GRUB will
treat this as a CPU physical address as well, so the kernel should not
treat it any differently.


>> ---
>>  drivers/video/fbdev/efifb.c | 5 +++++
>>  1 file changed, 5 insertions(+)
>>
>> diff --git a/drivers/video/fbdev/efifb.c b/drivers/video/fbdev/efifb.c
>> index 6daac8d..429cc85 100644
>> --- a/drivers/video/fbdev/efifb.c
>> +++ b/drivers/video/fbdev/efifb.c
>> @@ -431,6 +431,7 @@ static void efifb_fixup_resources(struct pci_dev *dev)
>>               .end = screen_info.lfb_base + screen_info.lfb_size - 1,
>>               .flags = IORESOURCE_MEM,
>>       };
>> +     struct pci_bus_region region;
>>       int i;
>>
>>       if (efifb_pci_dev || screen_info.orig_video_isVGA != VIDEO_TYPE_EFI)
>> @@ -442,6 +443,10 @@ static void efifb_fixup_resources(struct pci_dev *dev)
>>       if (!screen_res.start)
>>               return;
>>
>> +     region.start = screen_res.start;
>> +     region.end = screen_res.end;
>> +     pcibios_bus_to_resource(dev->bus, &screen_res, &region);
>> +
>>       for (i = 0; i <= PCI_STD_RESOURCE_END; i++) {
>>               struct resource *res = &dev->resource[i];
>>
>> --
>> 2.7.4
>>
>>
>> _______________________________________________
>> linux-arm-kernel mailing list
>> linux-arm-kernel@lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[Sinan Kaya]

Hi Ard,

On 6/22/2018 7:21 AM, Ard Biesheuvel wrote:
> Apologies for only bringing this up now, but I think this patch is
> wrong after all.
> 
> screen_info.lfb_base is supposed to be a CPU address, and so
> translating it like this is wrong. If you end up with a PCI address
> here, you have made a mistake in hacking support for PCI outbound
> translations into UEFI. Other users such as UEFI itself or GRUB will
> treat this as a CPU physical address as well, so the kernel should not
> treat it any differently.

The behavior I'm seeing is from a UEFI BIOS vendor. I did not write the
code for it...

I was asked to debug it.

I'd like to dive into your statement about UEFI and GRUB using this address
as physical addresses.

AFAIK, all PCI outbound requests go through PCI IO protocol in UEFI and the
translation information is hidden inside the UEFI PCI Host Bridge driver.
Drivers are not allowed to access PCI resources directly especially as a
memory mapped address.

This particular vendor is programming the BAR address into the GOP protocol.
Since the host bridge driver is doing a translation, we are hitting this
issue.

Is there a UEFI spec reference about the definition of this field?

Sinan

-- 
Sinan Kaya
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.

Re: [PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[Ard Biesheuvel]

On 22 June 2018 at 15:52, Sinan Kaya <okaya@codeaurora.org> wrote:
> Hi Ard,
>
> On 6/22/2018 7:21 AM, Ard Biesheuvel wrote:
>> Apologies for only bringing this up now, but I think this patch is
>> wrong after all.
>>
>> screen_info.lfb_base is supposed to be a CPU address, and so
>> translating it like this is wrong. If you end up with a PCI address
>> here, you have made a mistake in hacking support for PCI outbound
>> translations into UEFI. Other users such as UEFI itself or GRUB will
>> treat this as a CPU physical address as well, so the kernel should not
>> treat it any differently.
>
> The behavior I'm seeing is from a UEFI BIOS vendor. I did not write the
> code for it...
>
> I was asked to debug it.
>
> I'd like to dive into your statement about UEFI and GRUB using this address
> as physical addresses.
>
> AFAIK, all PCI outbound requests go through PCI IO protocol in UEFI and the
> translation information is hidden inside the UEFI PCI Host Bridge driver.
> Drivers are not allowed to access PCI resources directly especially as a
> memory mapped address.
>
> This particular vendor is programming the BAR address into the GOP protocol.
> Since the host bridge driver is doing a translation, we are hitting this
> issue.
>
> Is there a UEFI spec reference about the definition of this field?
>

Yes, it is part of the PCI I/O protocol definition. FrameBufferBase is
described as

"""
Base address of graphics linear frame buffer. Info contains
information required to allow software to draw directly to the
frame buffer without using Blt().Offset zero in
FrameBufferBase represents the upper left pixel of the
display.
"""

Re: [PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[Ard Biesheuvel]

On 22 June 2018 at 15:55, Ard Biesheuvel <ard.biesheuvel@linaro.org> wrote:
> On 22 June 2018 at 15:52, Sinan Kaya <okaya@codeaurora.org> wrote:
>> Hi Ard,
>>
>> On 6/22/2018 7:21 AM, Ard Biesheuvel wrote:
>>> Apologies for only bringing this up now, but I think this patch is
>>> wrong after all.
>>>
>>> screen_info.lfb_base is supposed to be a CPU address, and so
>>> translating it like this is wrong. If you end up with a PCI address
>>> here, you have made a mistake in hacking support for PCI outbound
>>> translations into UEFI. Other users such as UEFI itself or GRUB will
>>> treat this as a CPU physical address as well, so the kernel should not
>>> treat it any differently.
>>
>> The behavior I'm seeing is from a UEFI BIOS vendor. I did not write the
>> code for it...
>>
>> I was asked to debug it.
>>
>> I'd like to dive into your statement about UEFI and GRUB using this address
>> as physical addresses.
>>
>> AFAIK, all PCI outbound requests go through PCI IO protocol in UEFI and the
>> translation information is hidden inside the UEFI PCI Host Bridge driver.
>> Drivers are not allowed to access PCI resources directly especially as a
>> memory mapped address.
>>
>> This particular vendor is programming the BAR address into the GOP protocol.
>> Since the host bridge driver is doing a translation, we are hitting this
>> issue.
>>
>> Is there a UEFI spec reference about the definition of this field?
>>
>
> Yes, it is part of the PCI I/O protocol definition. FrameBufferBase is
> described as
>
> """
> Base address of graphics linear frame buffer. Info contains
> information required to allow software to draw directly to the
> frame buffer without using Blt().Offset zero in
> FrameBufferBase represents the upper left pixel of the
> display.
> """

I just tried AMD Radeon and NVidia graphics cards on a system with
non-1:1 mapped MMIO windows, and in both cases, the GOP protocol
structure is populated correctly, i.e., using the CPU address not the
PCIe address.

EDK2 only recently gained support for MMIO translation in the host
bridge driver, so I so wonder if this is a platform issue rather than
a driver issue. It may be worth a try to dump the results of
GetBarAttributes() of all PCI I/O protocol instances (either in UEFI
or in the stub), to double check that the correct values are returned.

Re: [PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[Sinan Kaya]

On 6/22/2018 2:01 PM, Ard Biesheuvel wrote:
>> Yes, it is part of the PCI I/O protocol definition. FrameBufferBase is
>> described as
>>
>> """
>> Base address of graphics linear frame buffer. Info contains
>> information required to allow software to draw directly to the
>> frame buffer without using Blt().Offset zero in
>> FrameBufferBase represents the upper left pixel of the
>> display.
>> """
> I just tried AMD Radeon and NVidia graphics cards on a system with
> non-1:1 mapped MMIO windows, and in both cases, the GOP protocol
> structure is populated correctly, i.e., using the CPU address not the
> PCIe address.
> 
> EDK2 only recently gained support for MMIO translation in the host
> bridge driver, so I so wonder if this is a platform issue rather than
> a driver issue. It may be worth a try to dump the results of
> GetBarAttributes() of all PCI I/O protocol instances (either in UEFI
> or in the stub), to double check that the correct values are returned.
> 

Thanks for checking out other platforms. I'll mark the issue as a BIOS
issue and bounce your feedback to the BIOS provider.

Let's hold onto this patch for the moment.

-- 
Sinan Kaya
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.

Re: [PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[Ard Biesheuvel]

On 22 June 2018 at 20:30, Sinan Kaya <okaya@codeaurora.org> wrote:
> On 6/22/2018 2:01 PM, Ard Biesheuvel wrote:
>>> Yes, it is part of the PCI I/O protocol definition. FrameBufferBase is
>>> described as
>>>
>>> """
>>> Base address of graphics linear frame buffer. Info contains
>>> information required to allow software to draw directly to the
>>> frame buffer without using Blt().Offset zero in
>>> FrameBufferBase represents the upper left pixel of the
>>> display.
>>> """
>> I just tried AMD Radeon and NVidia graphics cards on a system with
>> non-1:1 mapped MMIO windows, and in both cases, the GOP protocol
>> structure is populated correctly, i.e., using the CPU address not the
>> PCIe address.
>>
>> EDK2 only recently gained support for MMIO translation in the host
>> bridge driver, so I so wonder if this is a platform issue rather than
>> a driver issue. It may be worth a try to dump the results of
>> GetBarAttributes() of all PCI I/O protocol instances (either in UEFI
>> or in the stub), to double check that the correct values are returned.
>>
>
> Thanks for checking out other platforms. I'll mark the issue as a BIOS
> issue and bounce your feedback to the BIOS provider.
>

I screwed up my testing, unfortunately. Both the public AMD GOP driver
I tried, and the Nvidia GT218 under x86 emulation break when using
MMIO translation. However, GraphicsOutputDxe in the EDK2 tree gets it
right, and uses PciIo->GetBarAttributes() to get the address of the
framebuffer region, which will return the CPU address not the PCI
address.

> Let's hold onto this patch for the moment.
>

Yes. I'd like to get this resolved as well, but if the drivers are
dereferencing BAR values as CPU addresses, this is unlikely to be the
only thing that is broken under outbound translation.

Re: [PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[Ard Biesheuvel]

On 22 June 2018 at 21:29, Ard Biesheuvel <ard.biesheuvel@linaro.org> wrote:
> On 22 June 2018 at 20:30, Sinan Kaya <okaya@codeaurora.org> wrote:
>> On 6/22/2018 2:01 PM, Ard Biesheuvel wrote:
>>>> Yes, it is part of the PCI I/O protocol definition. FrameBufferBase is
>>>> described as
>>>>
>>>> """
>>>> Base address of graphics linear frame buffer. Info contains
>>>> information required to allow software to draw directly to the
>>>> frame buffer without using Blt().Offset zero in
>>>> FrameBufferBase represents the upper left pixel of the
>>>> display.
>>>> """
>>> I just tried AMD Radeon and NVidia graphics cards on a system with
>>> non-1:1 mapped MMIO windows, and in both cases, the GOP protocol
>>> structure is populated correctly, i.e., using the CPU address not the
>>> PCIe address.
>>>
>>> EDK2 only recently gained support for MMIO translation in the host
>>> bridge driver, so I so wonder if this is a platform issue rather than
>>> a driver issue. It may be worth a try to dump the results of
>>> GetBarAttributes() of all PCI I/O protocol instances (either in UEFI
>>> or in the stub), to double check that the correct values are returned.
>>>
>>
>> Thanks for checking out other platforms. I'll mark the issue as a BIOS
>> issue and bounce your feedback to the BIOS provider.
>>
>
> I screwed up my testing, unfortunately. Both the public AMD GOP driver
> I tried, and the Nvidia GT218 under x86 emulation break when using
> MMIO translation. However, GraphicsOutputDxe in the EDK2 tree gets it
> right, and uses PciIo->GetBarAttributes() to get the address of the
> framebuffer region, which will return the CPU address not the PCI
> address.
>
>> Let's hold onto this patch for the moment.
>>
>
> Yes. I'd like to get this resolved as well, but if the drivers are
> dereferencing BAR values as CPU addresses, this is unlikely to be the
> only thing that is broken under outbound translation.

Note that this was fixed fairly recently in EDK2, so BIOS vendors
providing UEFI firmware for ARM platforms with outbound MMIO
translation should probably incorporate this EDK2 patch

commit dc080d3b61e570e7a3163fc24afa6f8388d0c0bf
Author: Heyi Guo <heyi.guo@linaro.org>
Date:   Thu Feb 8 11:13:27 2018 +0800

    MdeModulePkg/PciBus: return CPU address for GetBarAttributes

    According to UEFI spec 2.7, PciIo->GetBarAttributes should return host
    address (CPU view ddress) rather than device address (PCI view
    address), and
    device address = host address + address translation offset,
    so we subtract translation from device address before returning.

Note that this is not the only MMIO translation related change made by
Heyi Guo to the generic PCI host bridge and bus drivers, but given
that those did not support MMIO translation at all, I take it your
affected platforms will already have their own changes to accommodate
this.

Re: [PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[okaya]

On 2018-06-25 04:20, Ard Biesheuvel wrote:
> On 22 June 2018 at 21:29, Ard Biesheuvel <ard.biesheuvel@linaro.org> 
> wrote:
>> On 22 June 2018 at 20:30, Sinan Kaya <okaya@codeaurora.org> wrote:
>>> On 6/22/2018 2:01 PM, Ard Biesheuvel wrote:
>>>>> Yes, it is part of the PCI I/O protocol definition. FrameBufferBase 
>>>>> is
>>>>> described as
>>>>> 
>>>>> """
>>>>> Base address of graphics linear frame buffer. Info contains
>>>>> information required to allow software to draw directly to the
>>>>> frame buffer without using Blt().Offset zero in
>>>>> FrameBufferBase represents the upper left pixel of the
>>>>> display.
>>>>> """
>>>> I just tried AMD Radeon and NVidia graphics cards on a system with
>>>> non-1:1 mapped MMIO windows, and in both cases, the GOP protocol
>>>> structure is populated correctly, i.e., using the CPU address not 
>>>> the
>>>> PCIe address.
>>>> 
>>>> EDK2 only recently gained support for MMIO translation in the host
>>>> bridge driver, so I so wonder if this is a platform issue rather 
>>>> than
>>>> a driver issue. It may be worth a try to dump the results of
>>>> GetBarAttributes() of all PCI I/O protocol instances (either in UEFI
>>>> or in the stub), to double check that the correct values are 
>>>> returned.
>>>> 
>>> 
>>> Thanks for checking out other platforms. I'll mark the issue as a 
>>> BIOS
>>> issue and bounce your feedback to the BIOS provider.
>>> 
>> 
>> I screwed up my testing, unfortunately. Both the public AMD GOP driver
>> I tried, and the Nvidia GT218 under x86 emulation break when using
>> MMIO translation. However, GraphicsOutputDxe in the EDK2 tree gets it
>> right, and uses PciIo->GetBarAttributes() to get the address of the
>> framebuffer region, which will return the CPU address not the PCI
>> address.
>> 
>>> Let's hold onto this patch for the moment.
>>> 
>> 
>> Yes. I'd like to get this resolved as well, but if the drivers are
>> dereferencing BAR values as CPU addresses, this is unlikely to be the
>> only thing that is broken under outbound translation.
> 
> Note that this was fixed fairly recently in EDK2, so BIOS vendors
> providing UEFI firmware for ARM platforms with outbound MMIO
> translation should probably incorporate this EDK2 patch
> 
> commit dc080d3b61e570e7a3163fc24afa6f8388d0c0bf
> Author: Heyi Guo <heyi.guo@linaro.org>
> Date:   Thu Feb 8 11:13:27 2018 +0800
> 
>     MdeModulePkg/PciBus: return CPU address for GetBarAttributes
> 
>     According to UEFI spec 2.7, PciIo->GetBarAttributes should return 
> host
>     address (CPU view ddress) rather than device address (PCI view
>     address), and
>     device address = host address + address translation offset,
>     so we subtract translation from device address before returning.
> 
> Note that this is not the only MMIO translation related change made by
> Heyi Guo to the generic PCI host bridge and bus drivers, but given
> that those did not support MMIO translation at all, I take it your
> affected platforms will already have their own changes to accommodate
> this.

Platform has been doing mmio translation for quite a while. Because all 
accesses go through pci io protocol, the rest of the UEFI never needed 
to be aware of bar address or do direct access.

This is the first time I hear of direct access. Maybe, GOP is a special 
case.

I started copying your response to the bios vendor.

They are probably missing that patch. I will pass it along.

Re: [PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[Sinan Kaya]

On 6/25/2018 11:52 AM, okaya@codeaurora.org wrote:
>> Note that this is not the only MMIO translation related change made by
>> Heyi Guo to the generic PCI host bridge and bus drivers, but given
>> that those did not support MMIO translation at all, I take it your
>> affected platforms will already have their own changes to accommodate
>> this.
> 
> Platform has been doing mmio translation for quite a while. Because all accesses go through pci io protocol, the rest of the UEFI never needed to be aware of bar address or do direct access.
> 
> This is the first time I hear of direct access. Maybe, GOP is a special case.
> 
> I started copying your response to the bios vendor.
> 
> They are probably missing that patch. I will pass it along.

I was informed that they fixed the issue in BIOS by presenting CPU physical
address instead of PCI bus address in FrameBufferBase of the AST GOP UEFI driver.

We can drop this patch now.

-- 
Sinan Kaya
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.

Re: [PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[Ard Biesheuvel]

On 25 June 2018 at 19:28, Sinan Kaya <okaya@codeaurora.org> wrote:
> On 6/25/2018 11:52 AM, okaya@codeaurora.org wrote:
>>> Note that this is not the only MMIO translation related change made by
>>> Heyi Guo to the generic PCI host bridge and bus drivers, but given
>>> that those did not support MMIO translation at all, I take it your
>>> affected platforms will already have their own changes to accommodate
>>> this.
>>
>> Platform has been doing mmio translation for quite a while. Because all accesses go through pci io protocol, the rest of the UEFI never needed to be aware of bar address or do direct access.
>>
>> This is the first time I hear of direct access. Maybe, GOP is a special case.
>>
>> I started copying your response to the bios vendor.
>>
>> They are probably missing that patch. I will pass it along.
>
> I was informed that they fixed the issue in BIOS by presenting CPU physical
> address instead of PCI bus address in FrameBufferBase of the AST GOP UEFI driver.
>
> We can drop this patch now.
>

Excellent! Thanks for following up with the vendor ...

Re: [PATCH V2 2/2] efi/fb: Convert PCI bus address to resource if translated by the bridge

[Sinan Kaya]

On 6/25/2018 1:29 PM, Ard Biesheuvel wrote:
>>> Platform has been doing mmio translation for quite a while. Because all accesses go through pci io protocol, the rest of the UEFI never needed to be aware of bar address or do direct access.
>>>
>>> This is the first time I hear of direct access. Maybe, GOP is a special case.
>>>
>>> I started copying your response to the bios vendor.
>>>
>>> They are probably missing that patch. I will pass it along.
>> I was informed that they fixed the issue in BIOS by presenting CPU physical
>> address instead of PCI bus address in FrameBufferBase of the AST GOP UEFI driver.
>>
>> We can drop this patch now.
>>
> Excellent! Thanks for following up with the vendor ...
> 

Sure, appreciate the help.

-- 
Sinan Kaya
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.

Re: [PATCH V2 1/2] efi/fb: Simplify fixup code to prefer struct resource

[Ard Biesheuvel]

On 18 May 2018 at 16:17, Sinan Kaya <okaya@codeaurora.org> wrote:
> Get rid of base and size variables in favor of a struct resource.
> The conditional for checking window can be replaced with
> resource_contains().
>
> Signed-off-by: Sinan Kaya <okaya@codeaurora.org>

Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

> ---
>  drivers/video/fbdev/efifb.c | 17 +++++++++++------
>  1 file changed, 11 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/video/fbdev/efifb.c b/drivers/video/fbdev/efifb.c
> index 46a4484..6daac8d 100644
> --- a/drivers/video/fbdev/efifb.c
> +++ b/drivers/video/fbdev/efifb.c
> @@ -426,17 +426,20 @@ static void record_efifb_bar_resource(struct pci_dev *dev, int idx, u64 offset)
>
>  static void efifb_fixup_resources(struct pci_dev *dev)
>  {
> -       u64 base = screen_info.lfb_base;
> -       u64 size = screen_info.lfb_size;
> +       struct resource screen_res = {
> +               .start = screen_info.lfb_base,
> +               .end = screen_info.lfb_base + screen_info.lfb_size - 1,
> +               .flags = IORESOURCE_MEM,
> +       };
>         int i;
>
>         if (efifb_pci_dev || screen_info.orig_video_isVGA != VIDEO_TYPE_EFI)
>                 return;
>
>         if (screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE)
> -               base |= (u64)screen_info.ext_lfb_base << 32;
> +               screen_res.start |= (u64)screen_info.ext_lfb_base << 32;
>
> -       if (!base)
> +       if (!screen_res.start)
>                 return;
>
>         for (i = 0; i <= PCI_STD_RESOURCE_END; i++) {
> @@ -445,8 +448,10 @@ static void efifb_fixup_resources(struct pci_dev *dev)
>                 if (!(res->flags & IORESOURCE_MEM))
>                         continue;
>
> -               if (res->start <= base && res->end >= base + size - 1) {
> -                       record_efifb_bar_resource(dev, i, base - res->start);
> +               if (resource_contains(res, &screen_res)) {
> +                       u64 win_offset =  screen_res.start - res->start;
> +
> +                       record_efifb_bar_resource(dev, i, win_offset);
>                         break;
>                 }
>         }
> --
> 2.7.4
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH V2 1/2] efi/fb: Simplify fixup code to prefer struct resource

[Bartlomiej Zolnierkiewicz]

On Wednesday, June 13, 2018 05:42:11 PM Ard Biesheuvel wrote:
> On 18 May 2018 at 16:17, Sinan Kaya <okaya@codeaurora.org> wrote:
> > Get rid of base and size variables in favor of a struct resource.
> > The conditional for checking window can be replaced with
> > resource_contains().
> >
> > Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
> 
> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics