[PATCH] ACPI / CPPC: Add support for guaranteed performance

[Srinivas Pandruvada]

The Continuous Performance Control Package can have guaranteed performance
field. Add support to read guaranteed performance.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx>
---
 Documentation/acpi/cppc_sysfs.txt |  2 ++
 drivers/acpi/cppc_acpi.c          | 10 ++++++++--
 include/acpi/cppc_acpi.h          |  1 +
 3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/Documentation/acpi/cppc_sysfs.txt b/Documentation/acpi/cppc_sysfs.txt
index f20fb445135d..812574d30717 100644
--- a/Documentation/acpi/cppc_sysfs.txt
+++ b/Documentation/acpi/cppc_sysfs.txt
@@ -22,6 +22,7 @@ $ ls -lR  /sys/devices/system/cpu/cpu0/acpi_cppc/
 /sys/devices/system/cpu/cpu0/acpi_cppc/:
 total 0
 -r--r--r-- 1 root root 65536 Mar  5 19:38 feedback_ctrs
+-r--r--r-- 1 root root 65536 Mar  5 19:38 guaranteed_perf
 -r--r--r-- 1 root root 65536 Mar  5 19:38 highest_perf
 -r--r--r-- 1 root root 65536 Mar  5 19:38 lowest_freq
 -r--r--r-- 1 root root 65536 Mar  5 19:38 lowest_nonlinear_perf
@@ -33,6 +34,7 @@ total 0
 
 --------------------------------------------------------------------------------
 
+* guaranteed_perf : Guaranteed performance of this processor (abstract scale).
 * highest_perf : Highest performance of this processor (abstract scale).
 * nominal_perf : Highest sustained performance of this processor (abstract scale).
 * lowest_nonlinear_perf : Lowest performance of this processor with nonlinear
diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
index d9ce4b162e2c..5babb9402f11 100644
--- a/drivers/acpi/cppc_acpi.c
+++ b/drivers/acpi/cppc_acpi.c
@@ -153,6 +153,7 @@ __ATTR(_name, 0444, show_##_name, NULL)
 	}								\
 	define_one_cppc_ro(member_name)
 
+show_cppc_data(cppc_get_perf_caps, cppc_perf_caps, guaranteed_perf);
 show_cppc_data(cppc_get_perf_caps, cppc_perf_caps, highest_perf);
 show_cppc_data(cppc_get_perf_caps, cppc_perf_caps, lowest_perf);
 show_cppc_data(cppc_get_perf_caps, cppc_perf_caps, nominal_perf);
@@ -189,6 +190,7 @@ static struct attribute *cppc_attrs[] = {
 	&nominal_perf.attr,
 	&nominal_freq.attr,
 	&lowest_freq.attr,
+	&guaranteed_perf.attr,
 	NULL
 };
 
@@ -1061,9 +1063,9 @@ int cppc_get_perf_caps(int cpunum, struct cppc_perf_caps *perf_caps)
 {
 	struct cpc_desc *cpc_desc = per_cpu(cpc_desc_ptr, cpunum);
 	struct cpc_register_resource *highest_reg, *lowest_reg,
-		*lowest_non_linear_reg, *nominal_reg,
+		*lowest_non_linear_reg, *nominal_reg, *guaranteed_reg,
 		*low_freq_reg = NULL, *nom_freq_reg = NULL;
-	u64 high, low, nom, min_nonlinear, low_f = 0, nom_f = 0;
+	u64 high, low, guaranteed, nom, min_nonlinear, low_f = 0, nom_f = 0;
 	int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpunum);
 	struct cppc_pcc_data *pcc_ss_data = NULL;
 	int ret = 0, regs_in_pcc = 0;
@@ -1079,6 +1081,7 @@ int cppc_get_perf_caps(int cpunum, struct cppc_perf_caps *perf_caps)
 	nominal_reg = &cpc_desc->cpc_regs[NOMINAL_PERF];
 	low_freq_reg = &cpc_desc->cpc_regs[LOWEST_FREQ];
 	nom_freq_reg = &cpc_desc->cpc_regs[NOMINAL_FREQ];
+	guaranteed_reg = &cpc_desc->cpc_regs[GUARANTEED_PERF];
 
 	/* Are any of the regs PCC ?*/
 	if (CPC_IN_PCC(highest_reg) || CPC_IN_PCC(lowest_reg) ||
@@ -1107,6 +1110,9 @@ int cppc_get_perf_caps(int cpunum, struct cppc_perf_caps *perf_caps)
 	cpc_read(cpunum, nominal_reg, &nom);
 	perf_caps->nominal_perf = nom;
 
+	cpc_read(cpunum, guaranteed_reg, &guaranteed);
+	perf_caps->guaranteed_perf = guaranteed;
+
 	cpc_read(cpunum, lowest_non_linear_reg, &min_nonlinear);
 	perf_caps->lowest_nonlinear_perf = min_nonlinear;
 
diff --git a/include/acpi/cppc_acpi.h b/include/acpi/cppc_acpi.h
index 8e0b8250a139..cf59e6210d27 100644
--- a/include/acpi/cppc_acpi.h
+++ b/include/acpi/cppc_acpi.h
@@ -104,6 +104,7 @@ enum cppc_regs {
  * today.
  */
 struct cppc_perf_caps {
+	u32 guaranteed_perf;
 	u32 highest_perf;
 	u32 nominal_perf;
 	u32 lowest_perf;
-- 
2.17.1