Re: [PATCH] x86/PCI: apply the AMD window fixup on resume as well

[Bjorn Helgaas]

On Tue, Jan 16, 2018 at 10:43:17AM +0100, Christian König wrote:
> We need to reprogram the register content during resume.
> 
> Signed-off-by: Christian König <christian.koenig@xxxxxxx>
> Reported-by: Tom St Denis <tom.stdenis@xxxxxxx>

Applied to for-linus for v4.15, thanks.

> ---
>  arch/x86/pci/fixup.c | 32 ++++++++++++++++++++------------
>  1 file changed, 20 insertions(+), 12 deletions(-)
> 
> diff --git a/arch/x86/pci/fixup.c b/arch/x86/pci/fixup.c
> index f6a26e3cb476..8f3b1a6278e6 100644
> --- a/arch/x86/pci/fixup.c
> +++ b/arch/x86/pci/fixup.c
> @@ -662,11 +662,11 @@ DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x2033, quirk_no_aersid);
>   */
>  static void pci_amd_enable_64bit_bar(struct pci_dev *dev)
>  {
> +	static const char *name = "PCI Bus 0000:00";
> +	struct resource *res, *conflict;
>  	u32 base, limit, high;
>  	struct pci_dev *other;
> -	struct resource *res;
>  	unsigned i;
> -	int r;
>  
>  	if (!(pci_probe & PCI_BIG_ROOT_WINDOW))
>  		return;
> @@ -707,21 +707,26 @@ static void pci_amd_enable_64bit_bar(struct pci_dev *dev)
>  	 * Allocate a 256GB window directly below the 0xfd00000000 hardware
>  	 * limit (see AMD Family 15h Models 30h-3Fh BKDG, sec 2.4.6).
>  	 */
> -	res->name = "PCI Bus 0000:00";
> +	res->name = name;
>  	res->flags = IORESOURCE_PREFETCH | IORESOURCE_MEM |
>  		IORESOURCE_MEM_64 | IORESOURCE_WINDOW;
>  	res->start = 0xbd00000000ull;
>  	res->end = 0xfd00000000ull - 1;
>  
> -	r = request_resource(&iomem_resource, res);
> -	if (r) {
> +	conflict = request_resource_conflict(&iomem_resource, res);
> +	if (conflict) {
>  		kfree(res);
> -		return;
> -	}
> +		if (conflict->name != name)
> +			return;
>  
> -	dev_info(&dev->dev, "adding root bus resource %pR (tainting kernel)\n",
> -		 res);
> -	add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK);
> +		/* We are resuming from suspend, just reprogram the regs. */
> +		res = conflict;
> +	} else {
> +		dev_info(&dev->dev, "adding root bus resource %pR (tainting kernel)\n",
> +			 res);
> +		add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK);
> +		pci_bus_add_resource(dev->bus, res, 0);
> +	}
>  
>  	base = ((res->start >> 8) & AMD_141b_MMIO_BASE_MMIOBASE_MASK) |
>  		AMD_141b_MMIO_BASE_RE_MASK | AMD_141b_MMIO_BASE_WE_MASK;
> @@ -733,13 +738,16 @@ static void pci_amd_enable_64bit_bar(struct pci_dev *dev)
>  	pci_write_config_dword(dev, AMD_141b_MMIO_HIGH(i), high);
>  	pci_write_config_dword(dev, AMD_141b_MMIO_LIMIT(i), limit);
>  	pci_write_config_dword(dev, AMD_141b_MMIO_BASE(i), base);
> -
> -	pci_bus_add_resource(dev->bus, res, 0);
>  }
>  DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_AMD, 0x1401, pci_amd_enable_64bit_bar);
>  DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_AMD, 0x141b, pci_amd_enable_64bit_bar);
>  DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_AMD, 0x1571, pci_amd_enable_64bit_bar);
>  DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_AMD, 0x15b1, pci_amd_enable_64bit_bar);
>  DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_AMD, 0x1601, pci_amd_enable_64bit_bar);
> +DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_AMD, 0x1401, pci_amd_enable_64bit_bar);
> +DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_AMD, 0x141b, pci_amd_enable_64bit_bar);
> +DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_AMD, 0x1571, pci_amd_enable_64bit_bar);
> +DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_AMD, 0x15b1, pci_amd_enable_64bit_bar);
> +DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_AMD, 0x1601, pci_amd_enable_64bit_bar);
>  
>  #endif
> -- 
> 2.11.0
>