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authorZhang Rui <rui.zhang@intel.com>2019-07-10 16:44:30 +0300
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2019-07-11 16:08:58 +0300
commit3382388d714891fc0f575926189f33d22e7c960b (patch)
treeaffa221ed25b32256fc34a920ff0a21b4485c21f /drivers/powercap/intel_rapl_msr.c
parent1193b1658d16f03cdb2edbac5f2a796ccca225af (diff)
downloadlinux-3382388d714891fc0f575926189f33d22e7c960b.tar.xz
intel_rapl: abstract RAPL common code
Split intel_rapl.c to intel_rapl_common.c and intel_rapl_msr.c, where intel_rapl_common.c contains the common code that can be used by both MSR and MMIO interface. intel_rapl_msr.c contains the implementation of RAPL MSR interface. Reviewed-by: Pandruvada, Srinivas <srinivas.pandruvada@intel.com> Tested-by: Pandruvada, Srinivas <srinivas.pandruvada@intel.com> Signed-off-by: Zhang Rui <rui.zhang@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/powercap/intel_rapl_msr.c')
-rw-r--r--drivers/powercap/intel_rapl_msr.c163
1 files changed, 163 insertions, 0 deletions
diff --git a/drivers/powercap/intel_rapl_msr.c b/drivers/powercap/intel_rapl_msr.c
new file mode 100644
index 000000000000..89645222e3e0
--- /dev/null
+++ b/drivers/powercap/intel_rapl_msr.c
@@ -0,0 +1,163 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Intel Running Average Power Limit (RAPL) Driver via MSR interface
+ * Copyright (c) 2019, Intel Corporation.
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/list.h>
+#include <linux/types.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/log2.h>
+#include <linux/bitmap.h>
+#include <linux/delay.h>
+#include <linux/sysfs.h>
+#include <linux/cpu.h>
+#include <linux/powercap.h>
+#include <linux/suspend.h>
+#include <linux/intel_rapl.h>
+#include <linux/processor.h>
+
+#include <asm/iosf_mbi.h>
+#include <asm/cpu_device_id.h>
+#include <asm/intel-family.h>
+
+/* Local defines */
+#define MSR_PLATFORM_POWER_LIMIT 0x0000065C
+
+/* private data for RAPL MSR Interface */
+static struct rapl_if_priv rapl_msr_priv = {
+ .reg_unit = MSR_RAPL_POWER_UNIT,
+ .regs[RAPL_DOMAIN_PACKAGE] = {
+ MSR_PKG_POWER_LIMIT, MSR_PKG_ENERGY_STATUS, MSR_PKG_PERF_STATUS, 0, MSR_PKG_POWER_INFO },
+ .regs[RAPL_DOMAIN_PP0] = {
+ MSR_PP0_POWER_LIMIT, MSR_PP0_ENERGY_STATUS, 0, MSR_PP0_POLICY, 0 },
+ .regs[RAPL_DOMAIN_PP1] = {
+ MSR_PP1_POWER_LIMIT, MSR_PP1_ENERGY_STATUS, 0, MSR_PP1_POLICY, 0 },
+ .regs[RAPL_DOMAIN_DRAM] = {
+ MSR_DRAM_POWER_LIMIT, MSR_DRAM_ENERGY_STATUS, MSR_DRAM_PERF_STATUS, 0, MSR_DRAM_POWER_INFO },
+ .regs[RAPL_DOMAIN_PLATFORM] = {
+ MSR_PLATFORM_POWER_LIMIT, MSR_PLATFORM_ENERGY_STATUS, 0, 0, 0},
+};
+
+/* Handles CPU hotplug on multi-socket systems.
+ * If a CPU goes online as the first CPU of the physical package
+ * we add the RAPL package to the system. Similarly, when the last
+ * CPU of the package is removed, we remove the RAPL package and its
+ * associated domains. Cooling devices are handled accordingly at
+ * per-domain level.
+ */
+static int rapl_cpu_online(unsigned int cpu)
+{
+ struct rapl_package *rp;
+
+ rp = rapl_find_package_domain(cpu, &rapl_msr_priv);
+ if (!rp) {
+ rp = rapl_add_package(cpu, &rapl_msr_priv);
+ if (IS_ERR(rp))
+ return PTR_ERR(rp);
+ }
+ cpumask_set_cpu(cpu, &rp->cpumask);
+ return 0;
+}
+
+static int rapl_cpu_down_prep(unsigned int cpu)
+{
+ struct rapl_package *rp;
+ int lead_cpu;
+
+ rp = rapl_find_package_domain(cpu, &rapl_msr_priv);
+ if (!rp)
+ return 0;
+
+ cpumask_clear_cpu(cpu, &rp->cpumask);
+ lead_cpu = cpumask_first(&rp->cpumask);
+ if (lead_cpu >= nr_cpu_ids)
+ rapl_remove_package(rp);
+ else if (rp->lead_cpu == cpu)
+ rp->lead_cpu = lead_cpu;
+ return 0;
+}
+
+static int rapl_msr_read_raw(int cpu, struct reg_action *ra)
+{
+ if (rdmsrl_safe_on_cpu(cpu, ra->reg, &ra->value)) {
+ pr_debug("failed to read msr 0x%x on cpu %d\n", ra->reg, cpu);
+ return -EIO;
+ }
+ ra->value &= ra->mask;
+ return 0;
+}
+
+static void rapl_msr_update_func(void *info)
+{
+ struct reg_action *ra = info;
+ u64 val;
+
+ ra->err = rdmsrl_safe(ra->reg, &val);
+ if (ra->err)
+ return;
+
+ val &= ~ra->mask;
+ val |= ra->value;
+
+ ra->err = wrmsrl_safe(ra->reg, val);
+}
+
+static int rapl_msr_write_raw(int cpu, struct reg_action *ra)
+{
+ int ret;
+
+ ret = smp_call_function_single(cpu, rapl_msr_update_func, ra, 1);
+ if (WARN_ON_ONCE(ret))
+ return ret;
+
+ return ra->err;
+}
+
+static int __init rapl_msr_init(void)
+{
+ int ret;
+
+ rapl_msr_priv.read_raw = rapl_msr_read_raw;
+ rapl_msr_priv.write_raw = rapl_msr_write_raw;
+
+ rapl_msr_priv.control_type = powercap_register_control_type(NULL, "intel-rapl", NULL);
+ if (IS_ERR(rapl_msr_priv.control_type)) {
+ pr_debug("failed to register powercap control_type.\n");
+ return PTR_ERR(rapl_msr_priv.control_type);
+ }
+
+ ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "powercap/rapl:online",
+ rapl_cpu_online, rapl_cpu_down_prep);
+ if (ret < 0)
+ goto out;
+ rapl_msr_priv.pcap_rapl_online = ret;
+
+ /* Don't bail out if PSys is not supported */
+ rapl_add_platform_domain(&rapl_msr_priv);
+
+ return 0;
+
+out:
+ if (ret)
+ powercap_unregister_control_type(rapl_msr_priv.control_type);
+ return ret;
+}
+
+static void __exit rapl_msr_exit(void)
+{
+ cpuhp_remove_state(rapl_msr_priv.pcap_rapl_online);
+ rapl_remove_platform_domain(&rapl_msr_priv);
+ powercap_unregister_control_type(rapl_msr_priv.control_type);
+}
+
+module_init(rapl_msr_init);
+module_exit(rapl_msr_exit);
+
+MODULE_DESCRIPTION("Driver for Intel RAPL (Running Average Power Limit) control via MSR interface");
+MODULE_AUTHOR("Zhang Rui <rui.zhang@intel.com>");
+MODULE_LICENSE("GPL v2");