Re: [PATCH 1/1] PCI: Add pci reset quirk for Nvidia GPUs

From: Sinan Kaya
Date: Fri Apr 23 2021 - 11:12:11 EST


+Alex,

On 4/23/2021 10:54 AM, Shanker Donthineni wrote:
> +static int reset_nvidia_gpu_quirk(struct pci_dev *dev, int probe)
> +{
> +#ifdef CONFIG_ACPI
> + acpi_handle handle = ACPI_HANDLE(&dev->dev);
> +
> + /*
> + * Check for the affected devices' ID range. If device is not in
> + * the affected range, return -ENOTTY indicating no device
> + * specific reset method is available.
> + */
> + if ((dev->device & 0xffc0) != 0x2340)
> + return -ENOTTY;
> +
> + /*
> + * Return -ENOTTY indicating no device-specific reset method if _RST
> + * method is not defined
> + */
> + if (!handle || !acpi_has_method(handle, "_RST"))
> + return -ENOTTY;
> +
> + /* Return 0 for probe phase indicating that we can reset this device */
> + if (probe)
> + return 0;
> +
> + /* Invoke _RST() method to perform the device-specific reset */
> + if (ACPI_FAILURE(acpi_evaluate_object(handle, "_RST", NULL, NULL))) {
> + pci_warn(dev, "Failed to reset the device\n");
> + return -EINVAL;
> + }
> + return 0;
> +#else
> + return -ENOTTY;
> +#endif
> +}

Interesting, some pieces of this function (especially the ACPI _RST)
could be generalized.