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

From: Srinivas Pandruvada
Date: Sun Oct 07 2018 - 00:43:11 EST


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