diff mbox series

[4/4] PCI: add a REBAR size quirk for Sapphire RX 5600 XT Pulse.

Message ID 20210105134404.1545-5-christian.koenig@amd.com
State New
Headers show
Series [1/4] pci: export pci_rebar_get_possible_sizes | expand

Commit Message

Christian König Jan. 5, 2021, 1:44 p.m. UTC 
Otherwise the CPU can't fully access the BAR.

Signed-off-by: Christian König <christian.koenig@amd.com>
---
 drivers/pci/pci.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

Comments

Ilia Mirkin Jan. 5, 2021, 4:11 p.m. UTC | #1 
On Tue, Jan 5, 2021 at 8:44 AM Christian König
<ckoenig.leichtzumerken@gmail.com> wrote:
>
> Otherwise the CPU can't fully access the BAR.
>
> Signed-off-by: Christian König <christian.koenig@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 16216186b51c..b66e4703c214 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -3577,7 +3577,14 @@ 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 = (cap & PCI_REBAR_CAP_SIZES) >> 4;
> +
> +       /* 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 == 0x700)
> +               cap == 0x7f00;

Perhaps you meant cap = 0x7f00?

> +
> +       return cap;
>  }
>  EXPORT_SYMBOL(pci_rebar_get_possible_sizes);
>
> --
> 2.25.1
>
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel
kernel test robot Jan. 5, 2021, 5:28 p.m. UTC | #2 
Hi "Christian,

I love your patch! Perhaps something to improve:

[auto build test WARNING on pci/next]
[also build test WARNING on linus/master v5.11-rc2 next-20210104]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Christian-K-nig/pci-export-pci_rebar_get_possible_sizes/20210105-224446
base:   https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git next
config: arm64-randconfig-r006-20210105 (attached as .config)
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 5c951623bc8965fa1e89660f2f5f4a2944e4981a)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install arm64 cross compiling tool for clang build
        # apt-get install binutils-aarch64-linux-gnu
        # https://github.com/0day-ci/linux/commit/6838a45fc2394ec88455e1fb3998ac865a077168
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Christian-K-nig/pci-export-pci_rebar_get_possible_sizes/20210105-224446
        git checkout 6838a45fc2394ec88455e1fb3998ac865a077168
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> drivers/pci/pci.c:3611:7: warning: equality comparison result unused [-Wunused-comparison]
                   cap == 0x7f00;
                   ~~~~^~~~~~~~~
   drivers/pci/pci.c:3611:7: note: use '=' to turn this equality comparison into an assignment
                   cap == 0x7f00;
                       ^~
                       =
   1 warning generated.


vim +3611 drivers/pci/pci.c

  3587	
  3588	/**
  3589	 * pci_rebar_get_possible_sizes - get possible sizes for BAR
  3590	 * @pdev: PCI device
  3591	 * @bar: BAR to query
  3592	 *
  3593	 * Get the possible sizes of a resizable BAR as bitmask defined in the spec
  3594	 * (bit 0=1MB, bit 19=512GB). Returns 0 if BAR isn't resizable.
  3595	 */
  3596	u32 pci_rebar_get_possible_sizes(struct pci_dev *pdev, int bar)
  3597	{
  3598		int pos;
  3599		u32 cap;
  3600	
  3601		pos = pci_rebar_find_pos(pdev, bar);
  3602		if (pos < 0)
  3603			return 0;
  3604	
  3605		pci_read_config_dword(pdev, pos + PCI_REBAR_CAP, &cap);
  3606		cap = (cap & PCI_REBAR_CAP_SIZES) >> 4;
  3607	
  3608		/* Sapphire RX 5600 XT Pulse has an invalid cap dword for BAR 0 */
  3609		if (pdev->vendor == PCI_VENDOR_ID_ATI && pdev->device == 0x731f &&
  3610		    bar == 0 && cap == 0x700)
> 3611			cap == 0x7f00;
  3612	
  3613		return cap;
  3614	}
  3615	EXPORT_SYMBOL(pci_rebar_get_possible_sizes);
  3616	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
Christian König Jan. 5, 2021, 5:43 p.m. UTC | #3 
Am 05.01.21 um 17:11 schrieb Ilia Mirkin:
> On Tue, Jan 5, 2021 at 8:44 AM Christian König
> <ckoenig.leichtzumerken@gmail.com> wrote:
>> Otherwise the CPU can't fully access the BAR.
>>
>> Signed-off-by: Christian König <christian.koenig@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 16216186b51c..b66e4703c214 100644
>> --- a/drivers/pci/pci.c
>> +++ b/drivers/pci/pci.c
>> @@ -3577,7 +3577,14 @@ 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 = (cap & PCI_REBAR_CAP_SIZES) >> 4;
>> +
>> +       /* 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 == 0x700)
>> +               cap == 0x7f00;
> Perhaps you meant cap = 0x7f00?

Ups, indeed! Thanks for pointing that out.

Christian.

>
>> +
>> +       return cap;
>>   }
>>   EXPORT_SYMBOL(pci_rebar_get_possible_sizes);
>>
>> --
>> 2.25.1
>>
>> _______________________________________________
>> dri-devel mailing list
>> dri-devel@lists.freedesktop.org
>> https://lists.freedesktop.org/mailman/listinfo/dri-devel
Dan Carpenter Jan. 5, 2021, 6:41 p.m. UTC | #4 
Hi Christian,

url:    https://github.com/0day-ci/linux/commits/Christian-K-nig/pci-export-pci_rebar_get_possible_sizes/20210105-224446 
base:   https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git  next
config: x86_64-randconfig-m001-20210105 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-15) 9.3.0

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>

smatch warnings:
drivers/pci/pci.c:3611 pci_rebar_get_possible_sizes() warn: statement has no effect 22

vim +3611 drivers/pci/pci.c

276b738deb5bf85 Christian König 2017-10-24  3596  u32 pci_rebar_get_possible_sizes(struct pci_dev *pdev, int bar)
276b738deb5bf85 Christian König 2017-10-24  3597  {
276b738deb5bf85 Christian König 2017-10-24  3598  	int pos;
276b738deb5bf85 Christian König 2017-10-24  3599  	u32 cap;
276b738deb5bf85 Christian König 2017-10-24  3600  
276b738deb5bf85 Christian König 2017-10-24  3601  	pos = pci_rebar_find_pos(pdev, bar);
276b738deb5bf85 Christian König 2017-10-24  3602  	if (pos < 0)
276b738deb5bf85 Christian König 2017-10-24  3603  		return 0;
276b738deb5bf85 Christian König 2017-10-24  3604  
276b738deb5bf85 Christian König 2017-10-24  3605  	pci_read_config_dword(pdev, pos + PCI_REBAR_CAP, &cap);
6838a45fc2394ec Christian König 2021-01-05  3606  	cap = (cap & PCI_REBAR_CAP_SIZES) >> 4;
6838a45fc2394ec Christian König 2021-01-05  3607  
6838a45fc2394ec Christian König 2021-01-05  3608  	/* Sapphire RX 5600 XT Pulse has an invalid cap dword for BAR 0 */
6838a45fc2394ec Christian König 2021-01-05  3609  	if (pdev->vendor == PCI_VENDOR_ID_ATI && pdev->device == 0x731f &&
6838a45fc2394ec Christian König 2021-01-05  3610  	    bar == 0 && cap == 0x700)
6838a45fc2394ec Christian König 2021-01-05 @3611  		cap == 0x7f00;

== vs =.

6838a45fc2394ec Christian König 2021-01-05  3612  
6838a45fc2394ec Christian König 2021-01-05  3613  	return cap;
276b738deb5bf85 Christian König 2017-10-24  3614  }

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
diff mbox series

Patch

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 16216186b51c..b66e4703c214 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -3577,7 +3577,14 @@  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 = (cap & PCI_REBAR_CAP_SIZES) >> 4;
+
+	/* 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 == 0x700)
+		cap == 0x7f00;
+
+	return cap;
 }
 EXPORT_SYMBOL(pci_rebar_get_possible_sizes);