[PATCH v7 11/14] cpufreq: amd-pstate: Add AMD P-State frequencies attributes

From: Huang Rui
Date: Thu Dec 23 2021 - 20:06:52 EST


Introduce sysfs attributes to get the different level processor
frequencies.

Signed-off-by: Huang Rui <ray.huang@xxxxxxx>
---
drivers/cpufreq/amd-pstate.c | 47 ++++++++++++++++++++++++++++++++++++
1 file changed, 47 insertions(+)

diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index 9e23efc7b9eb..dbb7eee11170 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -509,6 +509,52 @@ static int amd_pstate_cpu_exit(struct cpufreq_policy *policy)
return 0;
}

+/* Sysfs attributes */
+
+/*
+ * This frequency is to indicate the maximum hardware frequency.
+ * If boost is not active but supported, the frequency will be larger than the
+ * one in cpuinfo.
+ */
+static ssize_t show_amd_pstate_max_freq(struct cpufreq_policy *policy,
+ char *buf)
+{
+ int max_freq;
+ struct amd_cpudata *cpudata;
+
+ cpudata = policy->driver_data;
+
+ max_freq = amd_get_max_freq(cpudata);
+ if (max_freq < 0)
+ return max_freq;
+
+ return sprintf(&buf[0], "%u\n", max_freq);
+}
+
+static ssize_t show_amd_pstate_lowest_nonlinear_freq(struct cpufreq_policy *policy,
+ char *buf)
+{
+ int freq;
+ struct amd_cpudata *cpudata;
+
+ cpudata = policy->driver_data;
+
+ freq = amd_get_lowest_nonlinear_freq(cpudata);
+ if (freq < 0)
+ return freq;
+
+ return sprintf(&buf[0], "%u\n", freq);
+}
+
+cpufreq_freq_attr_ro(amd_pstate_max_freq);
+cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq);
+
+static struct freq_attr *amd_pstate_attr[] = {
+ &amd_pstate_max_freq,
+ &amd_pstate_lowest_nonlinear_freq,
+ NULL,
+};
+
static struct cpufreq_driver amd_pstate_driver = {
.flags = CPUFREQ_CONST_LOOPS | CPUFREQ_NEED_UPDATE_LIMITS,
.verify = amd_pstate_verify,
@@ -517,6 +563,7 @@ static struct cpufreq_driver amd_pstate_driver = {
.exit = amd_pstate_cpu_exit,
.set_boost = amd_pstate_set_boost,
.name = "amd-pstate",
+ .attr = amd_pstate_attr,
};

static int __init amd_pstate_init(void)
--
2.25.1