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ACPI: pci_link: Clear the dependencies after probe

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RISC-V platforms need to use dependencies between PCI host bridge, Link
devices and the interrupt controllers to ensure probe order. The
dependency is like below.

Interrupt controller <-- Link Device <-- PCI Host bridge.

If there is no dependency between Link device and PCI Host Bridge,
then PCI devices may be probed prior to Link devices.  If a PCI
device is probed before its Link device, we won't be able to find
its INTx mapping.

So, add the link device's HID to dependency honor list and clear the
dependency after probe is done so that the dependent devices are
unblocked to probe.

Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Link: https://patch.msgid.link/20240812005929.113499-9-sunilvl@ventanamicro.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Sunil V L 2024-08-12 06:29:20 +05:30 committed by Rafael J. Wysocki
parent 21734d29f8
commit 2cb9155d11
2 changed files with 3 additions and 0 deletions
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2
drivers/acpi/pci_link.c
View File

@ -748,6 +748,8 @@ static int acpi_pci_link_add(struct acpi_device *device,
if (result)
kfree(link);
acpi_dev_clear_dependencies(device);
return result < 0 ? result : 1;
}

1
drivers/acpi/scan.c
View File

@ -863,6 +863,7 @@ static const char * const acpi_honor_dep_ids[] = {
"INTC10CF", /* IVSC (MTL) driver must be loaded to allow i2c access to camera sensors */
"RSCV0001", /* RISC-V PLIC */
"RSCV0002", /* RISC-V APLIC */
"PNP0C0F", /* PCI Link Device */
NULL
};