ECN for "Extended-linear" addressing for direct-mapped memory-side caches adds a field in the SRAT Memory Side CAche Information Structure to indicate the address mode at the previously reserved bytes at offset 28. The field is described as: When Address Mode is 1 'Extended-Linear' it indicates that the associated address range (SRAT.MemoryAffinityStructure.Length) is comprised of the backing store capacity extended by the cache capacity. It is arranged such that there are N directly addressable aliases of a given cacheline where N is an integer ratio of target memory proximity domain size and the memory side cache size. Where the N aliased addresses for a given cacheline all share the same result for the operation 'address modulo cache size'. This setting is only allowed when 'Cache Associativity' is 'Direct Map'." Link: https://lore.kernel.org/linux-cxl/668333b17e4b2_5639294fd@xxxxxxxxxxxxxxxxxxxxxxxxx.notmuch/ Link: https://github.com/acpica/acpica/pull/961 Signed-off-by: Dave Jiang <dave.jiang@xxxxxxxxx> --- include/acpi/actbl1.h | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/include/acpi/actbl1.h b/include/acpi/actbl1.h index 841ef9f22795..95ddc858a0c3 100644 --- a/include/acpi/actbl1.h +++ b/include/acpi/actbl1.h @@ -1791,7 +1791,7 @@ struct acpi_hmat_cache { u32 reserved1; u64 cache_size; u32 cache_attributes; - u16 reserved2; + u16 address_mode; u16 number_of_SMBIOShandles; }; @@ -1803,6 +1803,9 @@ struct acpi_hmat_cache { #define ACPI_HMAT_WRITE_POLICY (0x0000F000) #define ACPI_HMAT_CACHE_LINE_SIZE (0xFFFF0000) +#define ACPI_HMAT_CACHE_MODE_UNKNOWN (0) +#define ACPI_HMAT_CACHE_MODE_EXTENDED_LINEAR (1) + /* Values for cache associativity flag */ #define ACPI_HMAT_CA_NONE (0) -- 2.46.1
