Messages in this thread | | | Date | Thu, 26 Oct 2023 11:51:50 -0500 | From | Bjorn Helgaas <> | Subject | Re: [RFC PATCH v2 13/21] irqchip: riscv-intc: Add ACPI support for AIA |
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On Thu, Oct 26, 2023 at 01:53:36AM +0530, Sunil V L wrote: > The RINTC subtype structure in MADT also has information about other > interrupt controllers like MMIO. So, save those information and provide > interfaces to retrieve them when required by corresponding drivers.
> @@ -218,7 +306,19 @@ static int __init riscv_intc_acpi_init(union acpi_subtable_headers *header,
> + * MSI controller (IMSIC) in RISC-V is optional. So, unless > + * IMSIC is discovered, set system wide MSI support as > + * unsupported. Once IMSIC is probed, MSI support will be set. > + */ > + pci_no_msi();
It doesn't seem like we should have to tell the PCI core about functionality we *don't* have.
I would think IMSIC would be detected before enumerating PCI devices that might use it, and if we *haven't* found an IMSIC by the time we get to pci_register_host_bridge(), would/should we set PCI_BUS_FLAGS_NO_MSI there?
I see Thomas is cc'd; he'd have better insight.
Bjorn
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