On 2024-06-07 8:53 am, Amit Singh Tomar wrote:
On Fri, Jun 07, 2024 at 12:21:54AM +0530, Amit Singh Tomar wrote:
[...]
diff --git a/drivers/acpi/processor_core.c
b/drivers/acpi/processor_core.c
index b203cfe28550..915713c0e9b7 100644
--- a/drivers/acpi/processor_core.c
+++ b/drivers/acpi/processor_core.c
@@ -215,6 +215,21 @@ phys_cpuid_t __init acpi_map_madt_entry(u32
acpi_id)
return rv;
}
+int __init acpi_get_madt_revision(void)
Wondering, if we can have a generic function (acpi_get_tbl_revision) to
obtain the revision number for any ACPI table, not just specific to
MADT?
We could - I don't think there would be users other than code in this
patch though so I thought it would not be necessary.
Right, it might not be essential now but I see that MPAM will be another
user of it once the MPAM patches are out.
https://git.kernel.org/pub/scm/linux/kernel/git/morse/linux.git/tree/drivers/acpi/arm64/mpam.c?h=mpam/snapshot/v6.7-rc2#n299
Not really; there's already plenty of ACPI code which checks the
revision of a table *while* also parsing other information from it, and
that MPAM code is doing the same. Using a standalone function to look up
the table, check one thing and throw it away, and then immediately have
to look it up again to do the rest would be needlessly overcomplicated.
The thing in the GIC case is that doing this semi-redundant lookup to
re-retrieve the top-level MADT header while we're already deep into
parsing its subtables is still the least-worst option, because the
alternative would be invasively churning the whole common MADT
abstraction to pass that information all the way down just for this one
slightly niche thing.
Thanks,
Robin.
