[PATCH v2 1/7] ACPI: CPPC: add perf control read API and clarify naming

Sumit Gupta posted 7 patches 1 month, 1 week ago
[PATCH v2 1/7] ACPI: CPPC: add perf control read API and clarify naming
Posted by Sumit Gupta 1 month, 1 week ago
Add cppc_get_perf_ctrls() to read performance control register values.
Rename existing APIs for clarity as:
- To distinguish between:
  - Feedback counters (fb_ctrs): Read-only performance monitoring data.
  - Performance controls (perf_ctrls): Read-write config registers.
- cppc_set_epp_perf() updates both EPP and Autonomous Selection.

API's renamed:
- cppc_set_perf() to cppc_set_perf_ctrls().
- cppc_get_perf_ctrs() to cppc_get_perf_fb_ctrs().
- cppc_get_perf_ctrs_sample() to cppc_get_perf_fb_ctrs_sample().
- cppc_set_epp_perf() to cppc_set_epp_and_autosel().

Remove redundant energy_perf field from 'struct cppc_perf_caps' since
the same information is available in 'struct cppc_perf_ctrls' which is
actively used.

All existing callers are updated to maintain compatibility.

Signed-off-by: Sumit Gupta <sumitg@nvidia.com>
---
 drivers/acpi/cppc_acpi.c       | 95 +++++++++++++++++++++++++++++-----
 drivers/cpufreq/amd-pstate.c   |  2 +-
 drivers/cpufreq/cppc_cpufreq.c | 26 +++++-----
 include/acpi/cppc_acpi.h       | 18 ++++---
 4 files changed, 106 insertions(+), 35 deletions(-)

diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
index 6b649031808f..24baaa298af3 100644
--- a/drivers/acpi/cppc_acpi.c
+++ b/drivers/acpi/cppc_acpi.c
@@ -58,7 +58,7 @@ struct cppc_pcc_data {
 	/*
 	 * Lock to provide controlled access to the PCC channel.
 	 *
-	 * For performance critical usecases(currently cppc_set_perf)
+	 * For performance critical usecases(currently cppc_set_perf_ctrls)
 	 *	We need to take read_lock and check if channel belongs to OSPM
 	 * before reading or writing to PCC subspace
 	 *	We need to take write_lock before transferring the channel
@@ -182,8 +182,8 @@ show_cppc_data(cppc_get_perf_caps, cppc_perf_caps, guaranteed_perf);
 show_cppc_data(cppc_get_perf_caps, cppc_perf_caps, lowest_freq);
 show_cppc_data(cppc_get_perf_caps, cppc_perf_caps, nominal_freq);
 
-show_cppc_data(cppc_get_perf_ctrs, cppc_perf_fb_ctrs, reference_perf);
-show_cppc_data(cppc_get_perf_ctrs, cppc_perf_fb_ctrs, wraparound_time);
+show_cppc_data(cppc_get_perf_fb_ctrs, cppc_perf_fb_ctrs, reference_perf);
+show_cppc_data(cppc_get_perf_fb_ctrs, cppc_perf_fb_ctrs, wraparound_time);
 
 /* Check for valid access_width, otherwise, fallback to using bit_width */
 #define GET_BIT_WIDTH(reg) ((reg)->access_width ? (8 << ((reg)->access_width - 1)) : (reg)->bit_width)
@@ -202,7 +202,7 @@ static ssize_t show_feedback_ctrs(struct kobject *kobj,
 	struct cppc_perf_fb_ctrs fb_ctrs = {0};
 	int ret;
 
-	ret = cppc_get_perf_ctrs(cpc_ptr->cpu_id, &fb_ctrs);
+	ret = cppc_get_perf_fb_ctrs(cpc_ptr->cpu_id, &fb_ctrs);
 	if (ret)
 		return ret;
 
@@ -1427,7 +1427,7 @@ EXPORT_SYMBOL_GPL(cppc_get_perf_caps);
  *
  * CPPC has flexibility about how CPU performance counters are accessed.
  * One of the choices is PCC regions, which can have a high access latency. This
- * routine allows callers of cppc_get_perf_ctrs() to know this ahead of time.
+ * routine allows callers of cppc_get_perf_fb_ctrs() to know this ahead of time.
  *
  * Return: true if any of the counters are in PCC regions, false otherwise
  */
@@ -1465,13 +1465,13 @@ bool cppc_perf_ctrs_in_pcc(void)
 EXPORT_SYMBOL_GPL(cppc_perf_ctrs_in_pcc);
 
 /**
- * cppc_get_perf_ctrs - Read a CPU's performance feedback counters.
+ * cppc_get_perf_fb_ctrs - Read a CPU's performance feedback counters.
  * @cpunum: CPU from which to read counters.
  * @perf_fb_ctrs: ptr to cppc_perf_fb_ctrs. See cppc_acpi.h
  *
  * Return: 0 for success with perf_fb_ctrs populated else -ERRNO.
  */
-int cppc_get_perf_ctrs(int cpunum, struct cppc_perf_fb_ctrs *perf_fb_ctrs)
+int cppc_get_perf_fb_ctrs(int cpunum, struct cppc_perf_fb_ctrs *perf_fb_ctrs)
 {
 	struct cpc_desc *cpc_desc = per_cpu(cpc_desc_ptr, cpunum);
 	struct cpc_register_resource *delivered_reg, *reference_reg,
@@ -1542,13 +1542,13 @@ int cppc_get_perf_ctrs(int cpunum, struct cppc_perf_fb_ctrs *perf_fb_ctrs)
 		up_write(&pcc_ss_data->pcc_lock);
 	return ret;
 }
-EXPORT_SYMBOL_GPL(cppc_get_perf_ctrs);
+EXPORT_SYMBOL_GPL(cppc_get_perf_fb_ctrs);
 
 /*
  * Set Energy Performance Preference Register value through
  * Performance Controls Interface
  */
-int cppc_set_epp_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls, bool enable)
+int cppc_set_epp_and_autosel(int cpu, struct cppc_perf_ctrls *perf_ctrls, bool enable)
 {
 	int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpu);
 	struct cpc_register_resource *epp_set_reg;
@@ -1599,7 +1599,7 @@ int cppc_set_epp_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls, bool enable)
 
 	return ret;
 }
-EXPORT_SYMBOL_GPL(cppc_set_epp_perf);
+EXPORT_SYMBOL_GPL(cppc_set_epp_and_autosel);
 
 /**
  * cppc_set_epp() - Write the EPP register.
@@ -1731,15 +1731,82 @@ int cppc_set_enable(int cpu, bool enable)
 	return cppc_set_reg_val(cpu, ENABLE, enable);
 }
 EXPORT_SYMBOL_GPL(cppc_set_enable);
+/**
+ * cppc_get_perf_ctrls - Get a CPU's performance controls.
+ * @cpu: CPU for which to get performance controls.
+ * @perf_ctrls: ptr to cppc_perf_ctrls. See cppc_acpi.h
+ *
+ * Return: 0 for success with perf_ctrls, -ERRNO otherwise.
+ */
+int cppc_get_perf_ctrls(int cpu, struct cppc_perf_ctrls *perf_ctrls)
+{
+	struct cpc_desc *cpc_desc = per_cpu(cpc_desc_ptr, cpu);
+	struct cpc_register_resource *desired_perf_reg, *min_perf_reg, *max_perf_reg,
+				     *energy_perf_reg;
+	u64 max, min, desired_perf, energy_perf;
+	int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpu);
+	struct cppc_pcc_data *pcc_ss_data = NULL;
+	int ret = 0, regs_in_pcc = 0;
+
+	if (!cpc_desc) {
+		pr_debug("No CPC descriptor for CPU:%d\n", cpu);
+		return -ENODEV;
+	}
+
+	desired_perf_reg = &cpc_desc->cpc_regs[DESIRED_PERF];
+	min_perf_reg = &cpc_desc->cpc_regs[MIN_PERF];
+	max_perf_reg = &cpc_desc->cpc_regs[MAX_PERF];
+	energy_perf_reg = &cpc_desc->cpc_regs[ENERGY_PERF];
+
+	/* Are any of the regs PCC ?*/
+	if (CPC_IN_PCC(desired_perf_reg) || CPC_IN_PCC(min_perf_reg) ||
+	    CPC_IN_PCC(max_perf_reg) || CPC_IN_PCC(energy_perf_reg)) {
+		if (pcc_ss_id < 0) {
+			pr_debug("Invalid pcc_ss_id\n");
+			return -ENODEV;
+		}
+		pcc_ss_data = pcc_data[pcc_ss_id];
+		regs_in_pcc = 1;
+		down_write(&pcc_ss_data->pcc_lock);
+		/* Ring doorbell once to update PCC subspace */
+		if (send_pcc_cmd(pcc_ss_id, CMD_READ) < 0) {
+			ret = -EIO;
+			goto out_err;
+		}
+	}
+
+	/* Read optional elements if present */
+	if (CPC_SUPPORTED(max_perf_reg))
+		cpc_read(cpu, max_perf_reg, &max);
+	perf_ctrls->max_perf = max;
+
+	if (CPC_SUPPORTED(min_perf_reg))
+		cpc_read(cpu, min_perf_reg, &min);
+	perf_ctrls->min_perf = min;
+
+	if (CPC_SUPPORTED(desired_perf_reg))
+		cpc_read(cpu, desired_perf_reg, &desired_perf);
+	perf_ctrls->desired_perf = desired_perf;
+
+	if (CPC_SUPPORTED(energy_perf_reg))
+		cpc_read(cpu, energy_perf_reg, &energy_perf);
+	perf_ctrls->energy_perf = energy_perf;
+
+out_err:
+	if (regs_in_pcc)
+		up_write(&pcc_ss_data->pcc_lock);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(cppc_get_perf_ctrls);
 
 /**
- * cppc_set_perf - Set a CPU's performance controls.
+ * cppc_set_perf_ctrls - Set a CPU's performance controls.
  * @cpu: CPU for which to set performance controls.
  * @perf_ctrls: ptr to cppc_perf_ctrls. See cppc_acpi.h
  *
  * Return: 0 for success, -ERRNO otherwise.
  */
-int cppc_set_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls)
+int cppc_set_perf_ctrls(int cpu, struct cppc_perf_ctrls *perf_ctrls)
 {
 	struct cpc_desc *cpc_desc = per_cpu(cpc_desc_ptr, cpu);
 	struct cpc_register_resource *desired_reg, *min_perf_reg, *max_perf_reg;
@@ -1803,7 +1870,7 @@ int cppc_set_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls)
 	/*
 	 * This is Phase-II where we transfer the ownership of PCC to Platform
 	 *
-	 * Short Summary: Basically if we think of a group of cppc_set_perf
+	 * Short Summary: Basically if we think of a group of cppc_set_perf_ctrls
 	 * requests that happened in short overlapping interval. The last CPU to
 	 * come out of Phase-I will enter Phase-II and ring the doorbell.
 	 *
@@ -1862,7 +1929,7 @@ int cppc_set_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls)
 	}
 	return ret;
 }
-EXPORT_SYMBOL_GPL(cppc_set_perf);
+EXPORT_SYMBOL_GPL(cppc_set_perf_ctrls);
 
 /**
  * cppc_get_transition_latency - returns frequency transition latency in ns
diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index bbc27ef9edf7..b98539d1a6aa 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -355,7 +355,7 @@ static int shmem_set_epp(struct cpufreq_policy *policy, u8 epp)
 		return 0;
 
 	perf_ctrls.energy_perf = epp;
-	ret = cppc_set_epp_perf(cpudata->cpu, &perf_ctrls, 1);
+	ret = cppc_set_epp_and_autosel(cpudata->cpu, &perf_ctrls, 1);
 	if (ret) {
 		pr_debug("failed to set energy perf value (%d)\n", ret);
 		return ret;
diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
index ecbeb12f46e6..e4666836306d 100644
--- a/drivers/cpufreq/cppc_cpufreq.c
+++ b/drivers/cpufreq/cppc_cpufreq.c
@@ -81,7 +81,7 @@ static void cppc_scale_freq_workfn(struct kthread_work *work)
 	cppc_fi = container_of(work, struct cppc_freq_invariance, work);
 	cpu_data = cppc_fi->cpu_data;
 
-	if (cppc_get_perf_ctrs(cppc_fi->cpu, &fb_ctrs)) {
+	if (cppc_get_perf_fb_ctrs(cppc_fi->cpu, &fb_ctrs)) {
 		pr_warn("%s: failed to read perf counters\n", __func__);
 		return;
 	}
@@ -115,7 +115,7 @@ static void cppc_scale_freq_tick(void)
 	struct cppc_freq_invariance *cppc_fi = &per_cpu(cppc_freq_inv, smp_processor_id());
 
 	/*
-	 * cppc_get_perf_ctrs() can potentially sleep, call that from the right
+	 * cppc_get_perf_fb_ctrs() can potentially sleep, call that from the right
 	 * context.
 	 */
 	irq_work_queue(&cppc_fi->irq_work);
@@ -141,7 +141,7 @@ static void cppc_cpufreq_cpu_fie_init(struct cpufreq_policy *policy)
 		kthread_init_work(&cppc_fi->work, cppc_scale_freq_workfn);
 		init_irq_work(&cppc_fi->irq_work, cppc_irq_work);
 
-		ret = cppc_get_perf_ctrs(cpu, &cppc_fi->prev_perf_fb_ctrs);
+		ret = cppc_get_perf_fb_ctrs(cpu, &cppc_fi->prev_perf_fb_ctrs);
 		if (ret) {
 			pr_warn("%s: failed to read perf counters for cpu:%d: %d\n",
 				__func__, cpu, ret);
@@ -271,7 +271,7 @@ static int cppc_cpufreq_set_target(struct cpufreq_policy *policy,
 	freqs.new = target_freq;
 
 	cpufreq_freq_transition_begin(policy, &freqs);
-	ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls);
+	ret = cppc_set_perf_ctrls(cpu, &cpu_data->perf_ctrls);
 	cpufreq_freq_transition_end(policy, &freqs, ret != 0);
 
 	if (ret)
@@ -291,7 +291,7 @@ static unsigned int cppc_cpufreq_fast_switch(struct cpufreq_policy *policy,
 
 	desired_perf = cppc_khz_to_perf(&cpu_data->perf_caps, target_freq);
 	cpu_data->perf_ctrls.desired_perf = desired_perf;
-	ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls);
+	ret = cppc_set_perf_ctrls(cpu, &cpu_data->perf_ctrls);
 
 	if (ret) {
 		pr_debug("Failed to set target on CPU:%d. ret:%d\n",
@@ -640,7 +640,7 @@ static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy)
 	policy->cur = cppc_perf_to_khz(caps, caps->highest_perf);
 	cpu_data->perf_ctrls.desired_perf =  caps->highest_perf;
 
-	ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls);
+	ret = cppc_set_perf_ctrls(cpu, &cpu_data->perf_ctrls);
 	if (ret) {
 		pr_debug("Err setting perf value:%d on CPU:%d. ret:%d\n",
 			 caps->highest_perf, cpu, ret);
@@ -666,7 +666,7 @@ static void cppc_cpufreq_cpu_exit(struct cpufreq_policy *policy)
 
 	cpu_data->perf_ctrls.desired_perf = caps->lowest_perf;
 
-	ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls);
+	ret = cppc_set_perf_ctrls(cpu, &cpu_data->perf_ctrls);
 	if (ret)
 		pr_debug("Err setting perf value:%d on CPU:%d. ret:%d\n",
 			 caps->lowest_perf, cpu, ret);
@@ -705,19 +705,19 @@ static int cppc_perf_from_fbctrs(struct cppc_perf_fb_ctrs *fb_ctrs_t0,
 	return (reference_perf * delta_delivered) / delta_reference;
 }
 
-static int cppc_get_perf_ctrs_sample(int cpu,
-				     struct cppc_perf_fb_ctrs *fb_ctrs_t0,
-				     struct cppc_perf_fb_ctrs *fb_ctrs_t1)
+static int cppc_get_perf_fb_ctrs_sample(int cpu,
+					struct cppc_perf_fb_ctrs *fb_ctrs_t0,
+					struct cppc_perf_fb_ctrs *fb_ctrs_t1)
 {
 	int ret;
 
-	ret = cppc_get_perf_ctrs(cpu, fb_ctrs_t0);
+	ret = cppc_get_perf_fb_ctrs(cpu, fb_ctrs_t0);
 	if (ret)
 		return ret;
 
 	udelay(2); /* 2usec delay between sampling */
 
-	return cppc_get_perf_ctrs(cpu, fb_ctrs_t1);
+	return cppc_get_perf_fb_ctrs(cpu, fb_ctrs_t1);
 }
 
 static unsigned int cppc_cpufreq_get_rate(unsigned int cpu)
@@ -735,7 +735,7 @@ static unsigned int cppc_cpufreq_get_rate(unsigned int cpu)
 
 	cpufreq_cpu_put(policy);
 
-	ret = cppc_get_perf_ctrs_sample(cpu, &fb_ctrs_t0, &fb_ctrs_t1);
+	ret = cppc_get_perf_fb_ctrs_sample(cpu, &fb_ctrs_t0, &fb_ctrs_t1);
 	if (ret) {
 		if (ret == -EFAULT)
 			/* Any of the associated CPPC regs is 0. */
diff --git a/include/acpi/cppc_acpi.h b/include/acpi/cppc_acpi.h
index 20f3d62e7a16..2f2dbeeced65 100644
--- a/include/acpi/cppc_acpi.h
+++ b/include/acpi/cppc_acpi.h
@@ -119,7 +119,6 @@ struct cppc_perf_caps {
 	u32 lowest_nonlinear_perf;
 	u32 lowest_freq;
 	u32 nominal_freq;
-	u32 energy_perf;
 	bool auto_sel;
 };
 
@@ -150,8 +149,9 @@ struct cppc_cpudata {
 extern int cppc_get_desired_perf(int cpunum, u64 *desired_perf);
 extern int cppc_get_nominal_perf(int cpunum, u64 *nominal_perf);
 extern int cppc_get_highest_perf(int cpunum, u64 *highest_perf);
-extern int cppc_get_perf_ctrs(int cpu, struct cppc_perf_fb_ctrs *perf_fb_ctrs);
-extern int cppc_set_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls);
+extern int cppc_get_perf_fb_ctrs(int cpu, struct cppc_perf_fb_ctrs *perf_fb_ctrs);
+extern int cppc_get_perf_ctrls(int cpu, struct cppc_perf_ctrls *perf_ctrls);
+extern int cppc_set_perf_ctrls(int cpu, struct cppc_perf_ctrls *perf_ctrls);
 extern int cppc_set_enable(int cpu, bool enable);
 extern int cppc_get_perf_caps(int cpu, struct cppc_perf_caps *caps);
 extern bool cppc_perf_ctrs_in_pcc(void);
@@ -166,7 +166,7 @@ extern bool cpc_supported_by_cpu(void);
 extern int cpc_read_ffh(int cpunum, struct cpc_reg *reg, u64 *val);
 extern int cpc_write_ffh(int cpunum, struct cpc_reg *reg, u64 val);
 extern int cppc_get_epp_perf(int cpunum, u64 *epp_perf);
-extern int cppc_set_epp_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls, bool enable);
+extern int cppc_set_epp_and_autosel(int cpu, struct cppc_perf_ctrls *perf_ctrls, bool enable);
 extern int cppc_set_epp(int cpu, u64 epp_val);
 extern int cppc_get_auto_act_window(int cpu, u64 *auto_act_window);
 extern int cppc_set_auto_act_window(int cpu, u64 auto_act_window);
@@ -188,11 +188,15 @@ static inline int cppc_get_highest_perf(int cpunum, u64 *highest_perf)
 {
 	return -EOPNOTSUPP;
 }
-static inline int cppc_get_perf_ctrs(int cpu, struct cppc_perf_fb_ctrs *perf_fb_ctrs)
+static inline int cppc_get_perf_fb_ctrs(int cpu, struct cppc_perf_fb_ctrs *perf_fb_ctrs)
+{
+	return -EOPNOTSUPP;
+}
+static inline int cppc_get_perf_ctrls(int cpu, struct cppc_perf_ctrls *perf_ctrls)
 {
 	return -EOPNOTSUPP;
 }
-static inline int cppc_set_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls)
+static inline int cppc_set_perf_ctrls(int cpu, struct cppc_perf_ctrls *perf_ctrls)
 {
 	return -EOPNOTSUPP;
 }
@@ -232,7 +236,7 @@ static inline int cpc_write_ffh(int cpunum, struct cpc_reg *reg, u64 val)
 {
 	return -EOPNOTSUPP;
 }
-static inline int cppc_set_epp_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls, bool enable)
+static inline int cppc_set_epp_and_autosel(int cpu, struct cppc_perf_ctrls *perf_ctrls, bool enable)
 {
 	return -EOPNOTSUPP;
 }
-- 
2.34.1
Re: [PATCH v2 1/7] ACPI: CPPC: add perf control read API and clarify naming
Posted by kernel test robot 1 month, 1 week ago
Hi Sumit,

kernel test robot noticed the following build errors:

[auto build test ERROR on rafael-pm/linux-next]
[also build test ERROR on rafael-pm/bleeding-edge linus/master v6.17-rc3 next-20250825]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Sumit-Gupta/ACPI-CPPC-add-perf-control-read-API-and-clarify-naming/20250824-040531
base:   https://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git linux-next
patch link:    https://lore.kernel.org/r/20250823200121.1320197-2-sumitg%40nvidia.com
patch subject: [PATCH v2 1/7] ACPI: CPPC: add perf control read API and clarify naming
config: x86_64-kexec (https://download.01.org/0day-ci/archive/20250826/202508260711.I7imWLTG-lkp@intel.com/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250826/202508260711.I7imWLTG-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202508260711.I7imWLTG-lkp@intel.com/

All errors (new ones prefixed by >>):

>> drivers/cpufreq/amd-pstate.c:524:8: error: call to undeclared function 'cppc_set_perf'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
     524 |         ret = cppc_set_perf(cpudata->cpu, &perf_ctrls);
         |               ^
   drivers/cpufreq/amd-pstate.c:524:8: note: did you mean 'cppc_set_epp'?
   include/acpi/cppc_acpi.h:170:12: note: 'cppc_set_epp' declared here
     170 | extern int cppc_set_epp(int cpu, u64 epp_val);
         |            ^
   1 error generated.


vim +/cppc_set_perf +524 drivers/cpufreq/amd-pstate.c

e059c184da47e9 Huang Rui         2021-12-24  480  
77fbea69b0ffad Mario Limonciello 2024-12-09  481  static int shmem_update_perf(struct cpufreq_policy *policy, u8 min_perf,
555bbe67a622b2 Dhananjay Ugwekar 2025-02-05  482  			     u8 des_perf, u8 max_perf, u8 epp, bool fast_switch)
e059c184da47e9 Huang Rui         2021-12-24  483  {
77fbea69b0ffad Mario Limonciello 2024-12-09  484  	struct amd_cpudata *cpudata = policy->driver_data;
e059c184da47e9 Huang Rui         2021-12-24  485  	struct cppc_perf_ctrls perf_ctrls;
9f5daa2f2f6ddd Mario Limonciello 2024-12-09  486  	u64 value, prev;
9f5daa2f2f6ddd Mario Limonciello 2024-12-09  487  	int ret;
e059c184da47e9 Huang Rui         2021-12-24  488  
fff395796917ac Mario Limonciello 2024-12-09  489  	if (cppc_state == AMD_PSTATE_ACTIVE) {
77fbea69b0ffad Mario Limonciello 2024-12-09  490  		int ret = shmem_set_epp(policy, epp);
fff395796917ac Mario Limonciello 2024-12-09  491  
fff395796917ac Mario Limonciello 2024-12-09  492  		if (ret)
fff395796917ac Mario Limonciello 2024-12-09  493  			return ret;
fff395796917ac Mario Limonciello 2024-12-09  494  	}
fff395796917ac Mario Limonciello 2024-12-09  495  
9f5daa2f2f6ddd Mario Limonciello 2024-12-09  496  	value = prev = READ_ONCE(cpudata->cppc_req_cached);
9f5daa2f2f6ddd Mario Limonciello 2024-12-09  497  
9f5daa2f2f6ddd Mario Limonciello 2024-12-09  498  	value &= ~(AMD_CPPC_MAX_PERF_MASK | AMD_CPPC_MIN_PERF_MASK |
9f5daa2f2f6ddd Mario Limonciello 2024-12-09  499  		   AMD_CPPC_DES_PERF_MASK | AMD_CPPC_EPP_PERF_MASK);
9f5daa2f2f6ddd Mario Limonciello 2024-12-09  500  	value |= FIELD_PREP(AMD_CPPC_MAX_PERF_MASK, max_perf);
9f5daa2f2f6ddd Mario Limonciello 2024-12-09  501  	value |= FIELD_PREP(AMD_CPPC_DES_PERF_MASK, des_perf);
9f5daa2f2f6ddd Mario Limonciello 2024-12-09  502  	value |= FIELD_PREP(AMD_CPPC_MIN_PERF_MASK, min_perf);
9f5daa2f2f6ddd Mario Limonciello 2024-12-09  503  	value |= FIELD_PREP(AMD_CPPC_EPP_PERF_MASK, epp);
9f5daa2f2f6ddd Mario Limonciello 2024-12-09  504  
77fbea69b0ffad Mario Limonciello 2024-12-09  505  	if (trace_amd_pstate_epp_perf_enabled()) {
77fbea69b0ffad Mario Limonciello 2024-12-09  506  		union perf_cached perf = READ_ONCE(cpudata->perf);
77fbea69b0ffad Mario Limonciello 2024-12-09  507  
77fbea69b0ffad Mario Limonciello 2024-12-09  508  		trace_amd_pstate_epp_perf(cpudata->cpu,
77fbea69b0ffad Mario Limonciello 2024-12-09  509  					  perf.highest_perf,
77fbea69b0ffad Mario Limonciello 2024-12-09  510  					  epp,
77fbea69b0ffad Mario Limonciello 2024-12-09  511  					  min_perf,
77fbea69b0ffad Mario Limonciello 2024-12-09  512  					  max_perf,
77fbea69b0ffad Mario Limonciello 2024-12-09  513  					  policy->boost_enabled,
77fbea69b0ffad Mario Limonciello 2024-12-09  514  					  value != prev);
77fbea69b0ffad Mario Limonciello 2024-12-09  515  	}
77fbea69b0ffad Mario Limonciello 2024-12-09  516  
9f5daa2f2f6ddd Mario Limonciello 2024-12-09  517  	if (value == prev)
9f5daa2f2f6ddd Mario Limonciello 2024-12-09  518  		return 0;
9f5daa2f2f6ddd Mario Limonciello 2024-12-09  519  
e059c184da47e9 Huang Rui         2021-12-24  520  	perf_ctrls.max_perf = max_perf;
e059c184da47e9 Huang Rui         2021-12-24  521  	perf_ctrls.min_perf = min_perf;
e059c184da47e9 Huang Rui         2021-12-24  522  	perf_ctrls.desired_perf = des_perf;
e059c184da47e9 Huang Rui         2021-12-24  523  
9f5daa2f2f6ddd Mario Limonciello 2024-12-09 @524  	ret = cppc_set_perf(cpudata->cpu, &perf_ctrls);
9f5daa2f2f6ddd Mario Limonciello 2024-12-09  525  	if (ret)
9f5daa2f2f6ddd Mario Limonciello 2024-12-09  526  		return ret;
9f5daa2f2f6ddd Mario Limonciello 2024-12-09  527  
9f5daa2f2f6ddd Mario Limonciello 2024-12-09  528  	WRITE_ONCE(cpudata->cppc_req_cached, value);
9f5daa2f2f6ddd Mario Limonciello 2024-12-09  529  
9f5daa2f2f6ddd Mario Limonciello 2024-12-09  530  	return 0;
e059c184da47e9 Huang Rui         2021-12-24  531  }
e059c184da47e9 Huang Rui         2021-12-24  532  

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Re: [PATCH v2 1/7] ACPI: CPPC: add perf control read API and clarify naming
Posted by Rafael J. Wysocki 1 month, 1 week ago
On Sat, Aug 23, 2025 at 10:02 PM Sumit Gupta <sumitg@nvidia.com> wrote:
>
> Add cppc_get_perf_ctrls() to read performance control register values.
> Rename existing APIs for clarity as:
> - To distinguish between:
>   - Feedback counters (fb_ctrs): Read-only performance monitoring data.
>   - Performance controls (perf_ctrls): Read-write config registers.
> - cppc_set_epp_perf() updates both EPP and Autonomous Selection.
>
> API's renamed:
> - cppc_set_perf() to cppc_set_perf_ctrls().
> - cppc_get_perf_ctrs() to cppc_get_perf_fb_ctrs().
> - cppc_get_perf_ctrs_sample() to cppc_get_perf_fb_ctrs_sample().
> - cppc_set_epp_perf() to cppc_set_epp_and_autosel().

> Remove redundant energy_perf field from 'struct cppc_perf_caps' since
> the same information is available in 'struct cppc_perf_ctrls' which is
> actively used.
>
> All existing callers are updated to maintain compatibility.

First, this is too much in one patch IMV and second, I honestly don't
see a reason for the renames above.

This generally makes tracking the code changes history harder.

Thanks!
Re: [PATCH v2 1/7] ACPI: CPPC: add perf control read API and clarify naming
Posted by Sumit Gupta 1 month ago
On 26/08/25 00:03, Rafael J. Wysocki wrote:
> External email: Use caution opening links or attachments
>
>
> On Sat, Aug 23, 2025 at 10:02 PM Sumit Gupta <sumitg@nvidia.com> wrote:
>> Add cppc_get_perf_ctrls() to read performance control register values.
>> Rename existing APIs for clarity as:
>> - To distinguish between:
>>    - Feedback counters (fb_ctrs): Read-only performance monitoring data.
>>    - Performance controls (perf_ctrls): Read-write config registers.
>> - cppc_set_epp_perf() updates both EPP and Autonomous Selection.
>>
>> API's renamed:
>> - cppc_set_perf() to cppc_set_perf_ctrls().
>> - cppc_get_perf_ctrs() to cppc_get_perf_fb_ctrs().
>> - cppc_get_perf_ctrs_sample() to cppc_get_perf_fb_ctrs_sample().
>> - cppc_set_epp_perf() to cppc_set_epp_and_autosel().
>> Remove redundant energy_perf field from 'struct cppc_perf_caps' since
>> the same information is available in 'struct cppc_perf_ctrls' which is
>> actively used.
>>
>> All existing callers are updated to maintain compatibility.
> First, this is too much in one patch IMV and second, I honestly don't
> see a reason for the renames above.
>
> This generally makes tracking the code changes history harder.
>
> Thanks!

Did the renaming for clarity and better readability.
If we don't want to do that then i can drop the renaming and keep other 
changes.
Also, split this patch into two as below:
         Patch1: Add cppc_get_perf() API.

         Patch2:
           - Update both EPP and Autonomous Selection in 
cppc_set_epp_perf().
           - Remove redundant energy_perf field from 'struct 
cppc_perf_caps'.

Thank you,
Sumit Gupta


Re: [PATCH v2 1/7] ACPI: CPPC: add perf control read API and clarify naming
Posted by Rafael J. Wysocki 1 month ago
On Mon, Sep 1, 2025 at 3:46 PM Sumit Gupta <sumitg@nvidia.com> wrote:
>
>
> On 26/08/25 00:03, Rafael J. Wysocki wrote:
> > External email: Use caution opening links or attachments
> >
> >
> > On Sat, Aug 23, 2025 at 10:02 PM Sumit Gupta <sumitg@nvidia.com> wrote:
> >> Add cppc_get_perf_ctrls() to read performance control register values.
> >> Rename existing APIs for clarity as:
> >> - To distinguish between:
> >>    - Feedback counters (fb_ctrs): Read-only performance monitoring data.
> >>    - Performance controls (perf_ctrls): Read-write config registers.
> >> - cppc_set_epp_perf() updates both EPP and Autonomous Selection.
> >>
> >> API's renamed:
> >> - cppc_set_perf() to cppc_set_perf_ctrls().
> >> - cppc_get_perf_ctrs() to cppc_get_perf_fb_ctrs().
> >> - cppc_get_perf_ctrs_sample() to cppc_get_perf_fb_ctrs_sample().
> >> - cppc_set_epp_perf() to cppc_set_epp_and_autosel().
> >> Remove redundant energy_perf field from 'struct cppc_perf_caps' since
> >> the same information is available in 'struct cppc_perf_ctrls' which is
> >> actively used.
> >>
> >> All existing callers are updated to maintain compatibility.
> >
> > First, this is too much in one patch IMV and second, I honestly don't
> > see a reason for the renames above.
> >
> > This generally makes tracking the code changes history harder.
> >
> > Thanks!
>
> Did the renaming for clarity and better readability.
> If we don't want to do that then i can drop the renaming and keep other
> changes.

Please do.

> Also, split this patch into two as below:
>          Patch1: Add cppc_get_perf() API.
>
>          Patch2:
>            - Update both EPP and Autonomous Selection in
> cppc_set_epp_perf().
>            - Remove redundant energy_perf field from 'struct
> cppc_perf_caps'.

Sounds reasonable to me.

Thanks!