driver inclusion category: feature bugzilla: https://atomgit.com/openeuler/kernel/issues/9163 ---------------------------------------------------------------------- Drive uncore frequency from L3C PMU counters by registering a devfreq-event device backed by in-kernel perf events. For each L3C PMU in this uncore's freq domain (matched via the hisilicon,scl-id property against an SCCL bitmap derived from related_cpus' MPIDRs), create a (utilization, cycles) counter pair and report the highest busy/total ratio across the domain. A per-HID table describes each revision's counter: HISI0214 (v2) exposes a busy event, HISI0215 (v3) an idle event, normalised to busy at read time. Restrict to ARM64 since the event path reads MPIDR via read_cpuid_mpidr(). Wire .get_dev_status to read the edev via devfreq_event_get_event() and report devfreq->previous_freq as the current frequency. With no edev, devfreq_event_get_event() returns -EINVAL and the status read fails rather than feeding governors a zero status. Signed-off-by: Jie Zhan <zhanjie9@hisilicon.com> --- drivers/devfreq/Kconfig | 3 +- drivers/devfreq/hisi_uncore_freq.c | 444 ++++++++++++++++++++++++++++- 2 files changed, 443 insertions(+), 4 deletions(-) diff --git a/drivers/devfreq/Kconfig b/drivers/devfreq/Kconfig index c999c4a1e567..32a0b2e449fd 100644 --- a/drivers/devfreq/Kconfig +++ b/drivers/devfreq/Kconfig @@ -92,9 +92,10 @@ config ARM_EXYNOS_BUS_DEVFREQ config ARM_HISI_UNCORE_DEVFREQ tristate "HiSilicon uncore DEVFREQ Driver" - depends on ACPI && ACPI_PPTT && PCC + depends on ARM64 && ACPI && ACPI_PPTT && PCC && PERF_EVENTS select DEVFREQ_GOV_PERFORMANCE select DEVFREQ_GOV_USERSPACE + select DEVFREQ_GOV_SIMPLE_ONDEMAND help This adds a DEVFREQ driver that manages uncore frequency scaling for HiSilicon Kunpeng SoCs. This enables runtime management of uncore diff --git a/drivers/devfreq/hisi_uncore_freq.c b/drivers/devfreq/hisi_uncore_freq.c index f32e499badce..f9e7010c07c8 100644 --- a/drivers/devfreq/hisi_uncore_freq.c +++ b/drivers/devfreq/hisi_uncore_freq.c @@ -8,23 +8,29 @@ #include <linux/acpi.h> #include <linux/bits.h> #include <linux/cleanup.h> +#include <linux/cpumask.h> #include <linux/devfreq.h> +#include <linux/devfreq-event.h> #include <linux/device.h> #include <linux/dev_printk.h> #include <linux/errno.h> #include <linux/iopoll.h> #include <linux/kernel.h> #include <linux/ktime.h> +#include <linux/math64.h> #include <linux/mailbox_client.h> #include <linux/module.h> #include <linux/mod_devicetable.h> #include <linux/mutex.h> +#include <linux/perf_event.h> #include <linux/platform_device.h> #include <linux/pm_opp.h> #include <linux/property.h> +#include <linux/smp.h> #include <linux/topology.h> #include <linux/units.h> #include <acpi/pcc.h> +#include <asm/cputype.h> #include "governor.h" @@ -61,6 +67,13 @@ enum hisi_uncore_freq_mode { #define HUCF_CAP_PLATFORM_CTRL BIT(0) +/* + * Upper bound for SCCL ids encoded in MPIDR affinity levels. Used to + * size the per-domain sccl bitmap; far above any realistic Kunpeng + * configuration (SCCL ids are typically single digits). + */ +#define HISI_MAX_SCCL 32 + /** * struct hisi_uncore_freq - hisi uncore frequency scaling device data * @dev: device of this frequency scaling driver @@ -72,6 +85,14 @@ enum hisi_uncore_freq_mode { * @devfreq: devfreq data of this hisi_uncore_freq device * @related_cpus: CPUs whose performance is majorly affected by this * uncore frequency domain + * @domain_sccl: bitmap of MPIDR-derived sccl ids covered by this + * freq domain; populated from related_cpus and used + * to match hisi uncore PMUs by their hisilicon,scl-id + * firmware property + * @edev: devfreq-event device backing get_dev_status, or NULL + * when no L3C PMU was matched for this freq domain + * @ondemand_data: tuning knobs for the simple_ondemand governor, + * chosen by L3C PMU revision during event registration * @cap: capability flag */ struct hisi_uncore_freq { @@ -83,6 +104,9 @@ struct hisi_uncore_freq { struct mutex pcc_lock; struct devfreq *devfreq; struct cpumask related_cpus; + DECLARE_BITMAP(domain_sccl, HISI_MAX_SCCL); + struct devfreq_event_dev *edev; + struct devfreq_simple_ondemand_data *ondemand_data; u32 cap; }; @@ -93,6 +117,402 @@ struct hisi_uncore_freq { /* Default polling interval in ms for devfreq governors*/ #define HUCF_DEFAULT_POLLING_MS 100 +#ifdef CONFIG_PM_DEVFREQ_EVENT + +#define HISI_L3C_EVENT_CYCLES 0x7f + +/* + * A PMU's utilization counter measures either busy or idle cycles, + * depending on the L3C revision. Record which, so the read path can + * normalise both to busy (busy = total - idle for the idle case). + */ +enum hucf_util_kind { + HUCF_UTIL_BUSY, + HUCF_UTIL_IDLE, +}; + +/* + * Per-HID description of the L3C uncore PMU. To support a new revision, + * add a row with its ACPI HID, the utilization event, its polarity, and + * the simple_ondemand tuning parameters for that revision. + */ +struct hisi_l3c_pmu_info { + const char *hid; + u32 util_event; + enum hucf_util_kind util_kind; + struct devfreq_simple_ondemand_data *ondemand_data; +}; + +static struct devfreq_simple_ondemand_data hisi_l3c_0214_odata = { + .upthreshold = 10, + .downdifferential = 0, +}; + +static struct devfreq_simple_ondemand_data hisi_l3c_0215_odata = { + .upthreshold = 75, + .downdifferential = 0, +}; + +static const struct hisi_l3c_pmu_info hisi_l3c_pmus[] = { + { "HISI0214", 0x90, HUCF_UTIL_BUSY, &hisi_l3c_0214_odata }, + { "HISI0215", 0x96, HUCF_UTIL_IDLE, &hisi_l3c_0215_odata }, +}; + +struct evset { + struct perf_event *util; + struct perf_event *total; + u64 prev_util; + u64 prev_total; + enum hucf_util_kind util_kind; +}; + +struct hisi_uncore_event { + struct devfreq_event_dev *edev; + struct devfreq_event_desc *desc; + struct evset *evset; + int nr_ev; +}; + +static const struct hisi_l3c_pmu_info *hisi_l3c_pmu_info_get(void) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(hisi_l3c_pmus); i++) + if (acpi_dev_present(hisi_l3c_pmus[i].hid, NULL, -1)) + return &hisi_l3c_pmus[i]; + + return NULL; +} + +static void hisi_uncore_read_mpidr_cb(void *info) +{ + u64 *mpidr = info; + + *mpidr = read_cpuid_mpidr(); +} + +/* + * Decode the SCCL and CCL ids for a remote @cpu from its MPIDR. + * Returns 0 on success, or a negative errno if @cpu is offline or otherwise + * unreachable. + */ +static int hisi_uncore_cpu_sccl_ccl(int cpu, int *sccl, int *ccl) +{ + u64 mpidr; + int rc; + + rc = smp_call_function_single(cpu, hisi_uncore_read_mpidr_cb, + &mpidr, 1); + if (rc) + return rc; + + if (mpidr & MPIDR_MT_BITMASK) { + *sccl = MPIDR_AFFINITY_LEVEL(mpidr, 3); + *ccl = MPIDR_AFFINITY_LEVEL(mpidr, 2); + } else { + *sccl = MPIDR_AFFINITY_LEVEL(mpidr, 2); + *ccl = MPIDR_AFFINITY_LEVEL(mpidr, 1); + } + + return 0; +} + +/* + * Build the per-domain bitmap of MPIDR-derived sccl ids covered by + * @uncore. Run after related_cpus has been populated and before any + * PMU matching is done. + * + * Only online CPUs are consulted (IPI-based MPIDR read can't reach + * offline CPUs). At probe time the related CPUs are normally all + * online; any SCCL that has at least one online CPU in the domain is + * recorded, which is sufficient for PMU matching. + */ +static void hisi_uncore_build_domain_sccl(struct hisi_uncore_freq *uncore) +{ + int cpu; + + bitmap_zero(uncore->domain_sccl, HISI_MAX_SCCL); + + for_each_cpu_and(cpu, &uncore->related_cpus, cpu_online_mask) { + int sccl, ccl; + + if (hisi_uncore_cpu_sccl_ccl(cpu, &sccl, &ccl)) + continue; + if (sccl >= 0 && sccl < HISI_MAX_SCCL) + set_bit(sccl, uncore->domain_sccl); + } +} + +/* + * Is the hisi uncore PMU described by @adev part of @uncore's freq + * domain? The PMU advertises its SCCL via hisilicon,scl-id; matching + * is a constant-time lookup in the precomputed domain_sccl bitmap. + */ +static bool hisi_uncore_pmu_in_domain(struct hisi_uncore_freq *uncore, + struct acpi_device *adev) +{ + u32 pmu_sccl; + + if (fwnode_property_read_u32(acpi_fwnode_handle(adev), + "hisilicon,scl-id", &pmu_sccl)) + return false; + + return pmu_sccl < HISI_MAX_SCCL && + test_bit(pmu_sccl, uncore->domain_sccl); +} + +static int hisi_uncore_event_enable(struct devfreq_event_dev *edev) +{ + struct hisi_uncore_event *event = devfreq_event_get_drvdata(edev); + int i; + + for (i = 0; i < event->nr_ev; i++) { + perf_event_enable(event->evset[i].util); + perf_event_enable(event->evset[i].total); + } + return 0; +} + +static int hisi_uncore_event_disable(struct devfreq_event_dev *edev) +{ + struct hisi_uncore_event *event = devfreq_event_get_drvdata(edev); + int i; + + for (i = 0; i < event->nr_ev; i++) { + perf_event_disable(event->evset[i].util); + perf_event_disable(event->evset[i].total); + } + return 0; +} + +static int hisi_uncore_event_set(struct devfreq_event_dev *edev) +{ + return 0; +} + +/* + * Return the highest load/total pair from the PMU in this freq domain over the + * latest poll interval. A PMU's utilization counter measures busy or idle + * cycles; both are normalised to load here. + */ +static int hisi_uncore_event_get(struct devfreq_event_dev *edev, + struct devfreq_event_data *edata) +{ + struct hisi_uncore_event *event = devfreq_event_get_drvdata(edev); + u64 cur_util, cur_total, d_util, d_total; + u64 max_load = 0, max_total = 1; + u64 ena_u, run_u, ena_t, run_t; + struct evset *e; + int i; + + for (i = 0; i < event->nr_ev; i++) { + e = &event->evset[i]; + + cur_util = perf_event_read_value(e->util, &ena_u, &run_u); + cur_total = perf_event_read_value(e->total, &ena_t, &run_t); + + d_util = cur_util - e->prev_util; + d_total = cur_total - e->prev_total; + e->prev_util = cur_util; + e->prev_total = cur_total; + + if (!d_total) + continue; + + /* + * If the PMU was multiplexed (running < enabled), scale the + * raw delta up to estimate the full-interval count. + */ + if (run_u && run_u != ena_u) + d_util = mul_u64_u64_div_u64(d_util, ena_u, run_u); + if (run_t && run_t != ena_t) + d_total = mul_u64_u64_div_u64(d_total, ena_t, run_t); + + d_util = min(d_util, d_total); + d_util = (e->util_kind == HUCF_UTIL_IDLE) ? d_total - d_util + : d_util; + + if (d_util * max_total > max_load * d_total) { + max_load = d_util; + max_total = d_total; + } + } + + edata->load_count = max_load; + edata->total_count = max_total; + + return 0; +} + +static const struct devfreq_event_ops hisi_uncore_event_ops = { + .enable = hisi_uncore_event_enable, + .disable = hisi_uncore_event_disable, + .set_event = hisi_uncore_event_set, + .get_event = hisi_uncore_event_get, +}; + +static void devm_hisi_uncore_disable_edev(void *data) +{ + devfreq_event_disable_edev(data); +} + +static void hisi_uncore_release_perf_events(void *data) +{ + struct hisi_uncore_event *event = data; + int i; + + for (i = 0; i < event->nr_ev; i++) { + if (event->evset[i].util) + perf_event_release_kernel(event->evset[i].util); + if (event->evset[i].total) + perf_event_release_kernel(event->evset[i].total); + } +} + +static int hisi_uncore_create_pmu_events(struct hisi_uncore_freq *uncore, + struct acpi_device *adev, + const struct hisi_l3c_pmu_info *info, + struct evset *evset) +{ + struct device *pmu_dev = acpi_get_first_physical_node(adev); + struct perf_event_attr attr = { + .size = sizeof(attr), + .disabled = 1, + }; + struct perf_event *pe_util, *pe_total; + int cpu, type; + + if (!pmu_dev) + return -EPROBE_DEFER; + + type = perf_pmu_type_by_parent_dev(pmu_dev); + if (type == -ENOENT) + return -EPROBE_DEFER; + if (type < 0) + return type; + + cpu = cpumask_first_and(&uncore->related_cpus, cpu_online_mask); + if (cpu >= nr_cpu_ids) + return -EAGAIN; + + attr.type = type; + attr.config = info->util_event; + pe_util = perf_event_create_kernel_counter(&attr, cpu, NULL, NULL, NULL); + if (IS_ERR(pe_util)) + return PTR_ERR(pe_util); + + attr.config = HISI_L3C_EVENT_CYCLES; + pe_total = perf_event_create_kernel_counter(&attr, cpu, NULL, NULL, NULL); + if (IS_ERR(pe_total)) { + perf_event_release_kernel(pe_util); + return PTR_ERR(pe_total); + } + + evset->util = pe_util; + evset->total = pe_total; + evset->util_kind = info->util_kind; + + return 0; +} + +static int hisi_uncore_devfreq_event_register(struct hisi_uncore_freq *uncore) +{ + const struct hisi_l3c_pmu_info *pmu_info; + struct device *dev = uncore->dev; + struct hisi_uncore_event *event; + struct devfreq_event_desc *desc; + struct devfreq_event_dev *edev; + struct acpi_device *adev; + int rc, max_pmus = 0; + + pmu_info = hisi_l3c_pmu_info_get(); + if (!pmu_info) + return 0; + + for_each_acpi_dev_match(adev, pmu_info->hid, NULL, -1) + max_pmus++; + + if (!max_pmus) + return 0; + + hisi_uncore_build_domain_sccl(uncore); + + event = devm_kzalloc(dev, sizeof(*event), GFP_KERNEL); + if (!event) + return -ENOMEM; + + event->evset = devm_kcalloc(dev, max_pmus, sizeof(*event->evset), + GFP_KERNEL); + if (!event->evset) + return -ENOMEM; + + /* Release any partially created perf events on probe failure. */ + rc = devm_add_action_or_reset(dev, hisi_uncore_release_perf_events, + event); + if (rc) + return rc; + + for_each_acpi_dev_match(adev, pmu_info->hid, NULL, -1) { + if (!hisi_uncore_pmu_in_domain(uncore, adev)) + continue; + + rc = hisi_uncore_create_pmu_events(uncore, adev, pmu_info, + &event->evset[event->nr_ev]); + if (rc) { + acpi_dev_put(adev); + /* PMU event support is optional. */ + if (rc == -EPROBE_DEFER || rc == -EAGAIN) { + dev_info(dev, "PMU unavailable, continue without devfreq-event support\n"); + return 0; + } + return rc; + } + event->nr_ev++; + } + + if (!event->nr_ev) + return 0; + + uncore->ondemand_data = pmu_info->ondemand_data; + + desc = devm_kzalloc(dev, sizeof(*desc), GFP_KERNEL); + if (!desc) + return -ENOMEM; + + *desc = (struct devfreq_event_desc) { + .name = dev_name(dev), + .driver_data = event, + .ops = &hisi_uncore_event_ops, + }; + + edev = devm_devfreq_event_add_edev(dev, desc); + if (IS_ERR(edev)) + return PTR_ERR(edev); + + event->edev = edev; + event->desc = desc; + uncore->edev = edev; + + rc = devfreq_event_enable_edev(edev); + if (rc) + return dev_err_probe(dev, rc, "Failed to enable devfreq-event\n"); + + return devm_add_action_or_reset(dev, devm_hisi_uncore_disable_edev, edev); +} + +/* + * Load the L3C PMU first when available so its perf PMU is registered before we + * look it up. This is a soft dependency: PMU event support is optional and the + * driver still provides basic frequency control without it. + */ +MODULE_SOFTDEP("pre: hisi_uncore_l3c_pmu"); +#else +static int hisi_uncore_devfreq_event_register(struct hisi_uncore_freq *uncore) +{ + return 0; +} +#endif /* CONFIG_PM_DEVFREQ_EVENT */ + static void hisi_uncore_free_pcc_chan(struct hisi_uncore_freq *uncore) { guard(mutex)(&uncore->pcc_lock); @@ -276,7 +696,19 @@ static int hisi_uncore_target(struct device *dev, unsigned long *freq, static int hisi_uncore_get_dev_status(struct device *dev, struct devfreq_dev_status *stat) { - /* Not used */ + struct hisi_uncore_freq *uncore = dev_get_drvdata(dev); + struct devfreq_event_data edata; + int rc; + + rc = devfreq_event_get_event(uncore->edev, &edata); + if (rc < 0) + return rc; + + stat->busy_time = edata.load_count; + stat->total_time = edata.total_count; + stat->current_frequency = uncore->devfreq ? + uncore->devfreq->previous_freq : 0; + return 0; } @@ -586,10 +1018,12 @@ static int hisi_uncore_devfreq_register(struct hisi_uncore_freq *uncore) if (data == HUCF_MODE_PLATFORM) uncore->devfreq = devm_devfreq_add_device(dev, profile, - hisi_platform_governor.name, NULL); + hisi_platform_governor.name, + uncore->ondemand_data); else uncore->devfreq = devm_devfreq_add_device(dev, profile, - DEVFREQ_GOV_PERFORMANCE, NULL); + DEVFREQ_GOV_PERFORMANCE, + uncore->ondemand_data); if (IS_ERR(uncore->devfreq)) return dev_err_probe(dev, PTR_ERR(uncore->devfreq), "Failed to add devfreq device\n"); @@ -633,6 +1067,10 @@ static int hisi_uncore_freq_probe(struct platform_device *pdev) if (rc) return dev_err_probe(dev, rc, "Failed to mark related cpus\n"); + rc = hisi_uncore_devfreq_event_register(uncore); + if (rc) + return dev_err_probe(dev, rc, "Failed to register devfreq event\n"); + rc = hisi_uncore_devfreq_register(uncore); if (rc) return dev_err_probe(dev, rc, "Failed to register devfreq\n"); -- 2.43.0