Commit 49d9e77e72cf ("ALSA: hda - Fix system panic when DMA > 40 bits for Nvidia audio controllers") simply disabled any DMA exceeding 32 bits for NVidia devices, even though they are capable of performing DMA up to 40 bits. On some architectures (such as arm64), system memory is not guaranteed to be 32-bit addressable by PCI devices, and so this change prevents NVidia devices from working on platforms such as AMD Seattle.
Since the original commit already mentioned that up to 40 bits of DMA is supported, and given that the code has been updated in the meantime to support a 40 bit DMA mask on other devices, revert commit 49d9e77e72cf and explicitly set the DMA mask to 40 bits for NVidia devices.
Signed-off-by: Ard Biesheuvel ard.biesheuvel@linaro.org --- sound/pci/hda/hda_intel.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c index c3469f756ec2..c64d986009a9 100644 --- a/sound/pci/hda/hda_intel.c +++ b/sound/pci/hda/hda_intel.c @@ -341,8 +341,7 @@ enum {
/* quirks for Nvidia */ #define AZX_DCAPS_PRESET_NVIDIA \ - (AZX_DCAPS_NO_MSI | /*AZX_DCAPS_ALIGN_BUFSIZE |*/ \ - AZX_DCAPS_NO_64BIT | AZX_DCAPS_CORBRP_SELF_CLEAR |\ + (AZX_DCAPS_NO_MSI | AZX_DCAPS_CORBRP_SELF_CLEAR |\ AZX_DCAPS_SNOOP_TYPE(NVIDIA))
#define AZX_DCAPS_PRESET_CTHDA \ @@ -1716,6 +1715,10 @@ static int azx_first_init(struct azx *chip) } }
+ /* NVidia hardware normally only supports up to 40 bits of DMA */ + if (chip->pci->vendor == PCI_VENDOR_ID_NVIDIA) + dma_bits = 40; + /* disable 64bit DMA address on some devices */ if (chip->driver_caps & AZX_DCAPS_NO_64BIT) { dev_dbg(card->dev, "Disabling 64bit DMA\n");