Introduce two macros to help with checking the support for optional CPPC
registers.
CPC_SUP_BUFFER_ONLY ensures that an expected BUFFER only register has a
register type of ACPI_TYPE_BUFFER and is not NULL.
REG_SUPPORTED decides which check to perform based the expected type of
the CPPC register.
Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@xxxxxxx>
---
drivers/acpi/cppc_acpi.c | 28 ++++++++++++++++++++++++++++
1 file changed, 28 insertions(+)
diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
index 15f103d7532b..c43de65531ae 100644
--- a/drivers/acpi/cppc_acpi.c
+++ b/drivers/acpi/cppc_acpi.c
@@ -111,6 +111,14 @@ static DEFINE_PER_CPU(struct cpc_desc *, cpc_desc_ptr);
#define CPC_SUPPORTED(cpc) ((cpc)->type == ACPI_TYPE_INTEGER ? \
!!(cpc)->cpc_entry.int_value : \
!IS_NULL_REG(&(cpc)->cpc_entry.reg))
+
+/*
+ * Evaluates to True if an optional cpc field is supported and is
+ * BUFFER only
+ */
+#define CPC_SUP_BUFFER_ONLY(cpc) ((cpc)->type == ACPI_TYPE_BUFFER && \
+ !IS_NULL_REG(&(cpc)->cpc_entry.reg))
+
/*
* Arbitrary Retries in case the remote processor is slow to respond
* to PCC commands. Keeping it high enough to cover emulators where
@@ -705,6 +713,26 @@ static bool is_cppc_supported(int revision, int num_ent)
* }
*/
+static bool is_buf_only(int reg_idx)
+{
+ switch (reg_idx) {
+ case HIGHEST_PERF:
+ case NOMINAL_PERF:
+ case LOW_NON_LINEAR_PERF:
+ case LOWEST_PERF:
+ case CTR_WRAP_TIME:
+ case AUTO_SEL_ENABLE:
+ case REFERENCE_PERF:
+ return false;
+ default:
+ return true;
+ }
+}
+
+#define REG_SUPPORTED(cpc, idx) (is_buf_only(idx) ? \
+ CPC_SUP_BUFFER_ONLY(&cpc->cpc_regs[idx]) : \
+ CPC_SUPPORTED(&cpc->cpc_regs[idx]))
+
/**
* acpi_cppc_processor_probe - Search for per CPU _CPC objects.
* @pr: Ptr to acpi_processor containing this CPU's logical ID.
--
2.17.1
