diff options
| -rw-r--r-- | drivers/acpi/cppc_acpi.c | 54 | ||||
| -rw-r--r-- | include/acpi/cppc_acpi.h | 2 |
2 files changed, 25 insertions, 31 deletions
diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c index 3c6d4ef87be0..1e15a9f25ae9 100644 --- a/drivers/acpi/cppc_acpi.c +++ b/drivers/acpi/cppc_acpi.c @@ -618,33 +618,6 @@ static int pcc_data_alloc(int pcc_ss_id) return 0; } -/* Check if CPPC revision + num_ent combination is supported */ -static bool is_cppc_supported(int revision, int num_ent) -{ - int expected_num_ent; - - switch (revision) { - case CPPC_V2_REV: - expected_num_ent = CPPC_V2_NUM_ENT; - break; - case CPPC_V3_REV: - expected_num_ent = CPPC_V3_NUM_ENT; - break; - default: - pr_debug("Firmware exports unsupported CPPC revision: %d\n", - revision); - return false; - } - - if (expected_num_ent != num_ent) { - pr_debug("Firmware exports %d entries. Expected: %d for CPPC rev:%d\n", - num_ent, expected_num_ent, revision); - return false; - } - - return true; -} - /* * An example CPC table looks like the following. * @@ -733,7 +706,6 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr) cpc_obj->type, pr->id); goto out_free; } - cpc_ptr->num_entries = num_ent; /* Second entry should be revision. */ cpc_obj = &out_obj->package.elements[1]; @@ -744,10 +716,32 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr) cpc_obj->type, pr->id); goto out_free; } - cpc_ptr->version = cpc_rev; - if (!is_cppc_supported(cpc_rev, num_ent)) + if (cpc_rev < CPPC_V2_REV) { + pr_debug("Unsupported _CPC Revision (%d) for CPU:%d\n", cpc_rev, + pr->id); + goto out_free; + } + + /* + * Disregard _CPC if the number of entries in the return pachage is not + * as expected, but support future revisions being proper supersets of + * the v3 and only causing more entries to be returned by _CPC. + */ + if ((cpc_rev == CPPC_V2_REV && num_ent != CPPC_V2_NUM_ENT) || + (cpc_rev == CPPC_V3_REV && num_ent != CPPC_V3_NUM_ENT) || + (cpc_rev > CPPC_V3_REV && num_ent <= CPPC_V3_NUM_ENT)) { + pr_debug("Unexpected number of _CPC return package entries (%d) for CPU:%d\n", + num_ent, pr->id); goto out_free; + } + if (cpc_rev > CPPC_V3_REV) { + num_ent = CPPC_V3_NUM_ENT; + cpc_rev = CPPC_V3_REV; + } + + cpc_ptr->num_entries = num_ent; + cpc_ptr->version = cpc_rev; /* Iterate through remaining entries in _CPC */ for (i = 2; i < num_ent; i++) { diff --git a/include/acpi/cppc_acpi.h b/include/acpi/cppc_acpi.h index d389bab54241..f73d357ecdf5 100644 --- a/include/acpi/cppc_acpi.h +++ b/include/acpi/cppc_acpi.h @@ -17,7 +17,7 @@ #include <acpi/pcc.h> #include <acpi/processor.h> -/* Support CPPCv2 and CPPCv3 */ +/* CPPCv2 and CPPCv3 support */ #define CPPC_V2_REV 2 #define CPPC_V3_REV 3 #define CPPC_V2_NUM_ENT 21 |