Re: [PATCH v7-incomplete 1/3] PCI: Move PRESERVE_BOOT_CONFIG _DSM evaluation to pci_register_host_bridge()

[Andy Shevchenko]

Sun, Apr 21, 2024 at 02:09:12PM -0500, Bjorn Helgaas kirjoitti:
> From: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> 
> Move the PRESERVE_BOOT_CONFIG _DSM evaluation from acpi_pci_root_create()
> to pci_register_host_bridge().
> 
> This will help unify the ACPI _DSM path and the DT-based
> "linux,pci-probe-only" paths.

..

> +bool pci_acpi_preserve_config(struct pci_host_bridge *host_bridge)
> +{
> +	if (ACPI_HANDLE(&host_bridge->dev)) {

Wouldn't the below looks nicer if you invert the conditional?

	handle = ACPI_HANDLE(...);

	if (!handle)
		return false;

	...

> +		union acpi_object *obj;
> +
> +		/*
> +		 * Evaluate the "PCI Boot Configuration" _DSM Function.  If it
> +		 * exists and returns 0, we must preserve any PCI resource
> +		 * assignments made by firmware for this host bridge.
> +		 */
> +		obj = acpi_evaluate_dsm_typed(ACPI_HANDLE(&host_bridge->dev),
> +					      &pci_acpi_dsm_guid,
> +					      1, DSM_PCI_PRESERVE_BOOT_CONFIG,
> +					      NULL, ACPI_TYPE_INTEGER);
> +		if (obj && obj->integer.value == 0)
> +			return true;
> +		ACPI_FREE(obj);
> +	}
> +
> +	return false;
> +}


-- 
With Best Regards,
Andy Shevchenko