Messages in this thread Patch in this message | | | From | Agustin Vega-Frias <> | Subject | [RFC V2 3/3] perf: qcom: Add Falkor CPU PMU IMPLEMENTATION DEFINED event support | Date | Thu, 7 Jun 2018 09:56:48 -0400 |
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Selection of these events can be envisioned as indexing them from a 3D matrix: - the first index selects a Region Event Selection Register (PMRESRx_EL0) - the second index selects a group from which only one event at a time can be selected - the third index selects the event
The event is encoded into perf_event_attr.config as 0xPRCCG, where: P [config:16 ] = prefix (flag that indicates a matrix-based event) R [config:12-15] = register (specifies the PMRESRx_EL0 instance) G [config:0-3 ] = group (specifies the event group) CC [config:4-11 ] = code (specifies the event)
Events with the P flag set to zero are treated as common PMUv3 events and are directly programmed into PMXEVTYPERx_EL0.
The first two indexes are set combining the RESR and group number with a base number and writing it into the architected PMXEVTYPER_EL0 register. The third index is set by writing the code into the bits corresponding with the group into the appropriate IMPLEMENTATION DEFINED PMRESRx_EL0 register.
Support for this extension is signaled by the presence of the Falkor PMU device node under each Falkor CPU device node in the DSDT ACPI table. E.g.:
Device (CPU0) { Name (_HID, "ACPI0007" /* Processor Device */) ... Device (PMU0) { Name (_HID, "QCOM8150") /* Qualcomm Falkor PMU device */ ... } }
Signed-off-by: Agustin Vega-Frias <agustinv@codeaurora.org> --- drivers/perf/Makefile | 2 +- drivers/perf/qcom_arm_pmu.c | 310 ++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 311 insertions(+), 1 deletion(-) create mode 100644 drivers/perf/qcom_arm_pmu.c
diff --git a/drivers/perf/Makefile b/drivers/perf/Makefile index b3902bd..a61afd9 100644 --- a/drivers/perf/Makefile +++ b/drivers/perf/Makefile @@ -3,7 +3,7 @@ obj-$(CONFIG_ARM_CCI_PMU) += arm-cci.o obj-$(CONFIG_ARM_CCN) += arm-ccn.o obj-$(CONFIG_ARM_DSU_PMU) += arm_dsu_pmu.o obj-$(CONFIG_ARM_PMU) += arm_pmu.o arm_pmu_platform.o -obj-$(CONFIG_ARM_PMU_ACPI) += arm_pmu_acpi.o +obj-$(CONFIG_ARM_PMU_ACPI) += arm_pmu_acpi.o qcom_arm_pmu.o obj-$(CONFIG_HISI_PMU) += hisilicon/ obj-$(CONFIG_QCOM_L2_PMU) += qcom_l2_pmu.o obj-$(CONFIG_QCOM_L3_PMU) += qcom_l3_pmu.o diff --git a/drivers/perf/qcom_arm_pmu.c b/drivers/perf/qcom_arm_pmu.c new file mode 100644 index 0000000..5cec756 --- /dev/null +++ b/drivers/perf/qcom_arm_pmu.c @@ -0,0 +1,310 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2018, The Linux Foundation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +/* + * Qualcomm Technologies CPU PMU IMPLEMENTATION DEFINED extensions support + * + * Current extensions supported: + * + * - Matrix-based microarchitectural events support + * + * Selection of these events can be envisioned as indexing them from + * a 3D matrix: + * - the first index selects a Region Event Selection Register (PMRESRx_EL0) + * - the second index selects a group from which only one event at a time + * can be selected + * - the third index selects the event + * + * The event is encoded into perf_event_attr.config as 0xPRCCG, where: + * P [config:16 ] = prefix (flag that indicates a matrix-based event) + * R [config:12-15] = register (specifies the PMRESRx_EL0 instance) + * G [config:0-3 ] = group (specifies the event group) + * CC [config:4-11 ] = code (specifies the event) + * + * Events with the P flag set to zero are treated as common PMUv3 events + * and are directly programmed into PMXEVTYPERx_EL0. + * + * The first two indexes are set combining the RESR and group number with + * a base number and writing it into the architected PMXEVTYPER_EL0 register. + * The third index is set by writing the code into the bits corresponding + * with the group into the appropriate IMPLEMENTATION DEFINED PMRESRx_EL0 + * register. + */ + +#include <linux/acpi.h> +#include <linux/perf/arm_pmu.h> + +#define pmresr0_el0 sys_reg(3, 5, 11, 3, 0) +#define pmresr1_el0 sys_reg(3, 5, 11, 3, 2) +#define pmresr2_el0 sys_reg(3, 5, 11, 3, 4) +#define pmxevcntcr_el0 sys_reg(3, 5, 11, 0, 3) + +#define QC_EVT_PFX_SHIFT 16 +#define QC_EVT_REG_SHIFT 12 +#define QC_EVT_CODE_SHIFT 4 +#define QC_EVT_GRP_SHIFT 0 +#define QC_EVT_PFX_MASK GENMASK(QC_EVT_PFX_SHIFT, QC_EVT_PFX_SHIFT) +#define QC_EVT_REG_MASK GENMASK(QC_EVT_REG_SHIFT + 3, QC_EVT_REG_SHIFT) +#define QC_EVT_CODE_MASK GENMASK(QC_EVT_CODE_SHIFT + 7, QC_EVT_CODE_SHIFT) +#define QC_EVT_GRP_MASK GENMASK(QC_EVT_GRP_SHIFT + 3, QC_EVT_GRP_SHIFT) +#define QC_EVT_PRG_MASK (QC_EVT_PFX_MASK | QC_EVT_REG_MASK | QC_EVT_GRP_MASK) +#define QC_EVT_PRG(event) ((event) & QC_EVT_PRG_MASK) +#define QC_EVT_REG(event) (((event) & QC_EVT_REG_MASK) >> QC_EVT_REG_SHIFT) +#define QC_EVT_CODE(event) (((event) & QC_EVT_CODE_MASK) >> QC_EVT_CODE_SHIFT) +#define QC_EVT_GROUP(event) (((event) & QC_EVT_GRP_MASK) >> QC_EVT_GRP_SHIFT) + +#define QC_MAX_GROUP 7 +#define QC_MAX_RESR 2 +#define QC_BITS_PER_GROUP 8 +#define QC_RESR_ENABLE BIT_ULL(63) +#define QC_RESR_EVT_BASE 0xd8 + +static struct arm_pmu *def_ops; + +static inline void falkor_write_pmresr(u64 reg, u64 val) +{ + if (reg == 0) + write_sysreg_s(val, pmresr0_el0); + else if (reg == 1) + write_sysreg_s(val, pmresr1_el0); + else + write_sysreg_s(val, pmresr2_el0); +} + +static inline u64 falkor_read_pmresr(u64 reg) +{ + return (reg == 0 ? read_sysreg_s(pmresr0_el0) : + reg == 1 ? read_sysreg_s(pmresr1_el0) : + read_sysreg_s(pmresr2_el0)); +} + +static void falkor_set_resr(u64 reg, u64 group, u64 code) +{ + u64 shift = group * QC_BITS_PER_GROUP; + u64 mask = GENMASK(shift + QC_BITS_PER_GROUP - 1, shift); + u64 val; + + val = falkor_read_pmresr(reg) & ~mask; + val |= (code << shift); + val |= QC_RESR_ENABLE; + falkor_write_pmresr(reg, val); +} + +static void falkor_clear_resr(u64 reg, u64 group) +{ + u32 shift = group * QC_BITS_PER_GROUP; + u64 mask = GENMASK(shift + QC_BITS_PER_GROUP - 1, shift); + u64 val = falkor_read_pmresr(reg) & ~mask; + + falkor_write_pmresr(reg, val == QC_RESR_ENABLE ? 0 : val); +} + +/* + * Check if e1 and e2 conflict with each other + * + * e1 is a matrix-based microarchitectural event we are checking against e2. + * A conflict exists if the events use the same reg, group, and a different + * code. Events with the same code are allowed because they could be using + * different filters (e.g. one to count user space and the other to count + * kernel space events). + */ +static inline int events_conflict(struct perf_event *e1, struct perf_event *e2) +{ + if ((e1 != e2) && + (e1->pmu == e2->pmu) && + (QC_EVT_PRG(e1->attr.config) == QC_EVT_PRG(e2->attr.config)) && + (QC_EVT_CODE(e1->attr.config) != QC_EVT_CODE(e2->attr.config))) { + pr_debug_ratelimited( + "Group exclusion: conflicting events %llx %llx\n", + e1->attr.config, + e2->attr.config); + return 1; + } + return 0; +} + +/* + * Check if the given event is valid for the PMU and if so return the value + * that can be used in PMXEVTYPER_EL0 to select the event + */ +static int falkor_map_event(struct perf_event *event) +{ + u64 reg = QC_EVT_REG(event->attr.config); + u64 group = QC_EVT_GROUP(event->attr.config); + struct perf_event *leader; + struct perf_event *sibling; + + if (!(event->attr.config & QC_EVT_PFX_MASK)) + /* Common PMUv3 event, forward to the original op */ + return def_ops->map_event(event); + + /* Is it a valid matrix event? */ + if ((group > QC_MAX_GROUP) || (reg > QC_MAX_RESR)) + return -ENOENT; + + /* If part of an event group, check if the event can be put in it */ + + leader = event->group_leader; + if (events_conflict(event, leader)) + return -ENOENT; + + for_each_sibling_event(sibling, leader) + if (events_conflict(event, sibling)) + return -ENOENT; + + return QC_RESR_EVT_BASE + reg*8 + group; +} + +/* + * Find a slot for the event on the current CPU + */ +static int falkor_get_event_idx(struct pmu_hw_events *cpuc, struct perf_event *event) +{ + int idx; + + if (!!(event->attr.config & QC_EVT_PFX_MASK)) + /* Matrix event, check for conflicts with existing events */ + for_each_set_bit(idx, cpuc->used_mask, ARMPMU_MAX_HWEVENTS) + if (cpuc->events[idx] && + events_conflict(event, cpuc->events[idx])) + return -ENOENT; + + /* Let the original op handle the rest */ + idx = def_ops->get_event_idx(cpuc, event); + + /* + * This is called for actually allocating the events, but also with + * a dummy pmu_hw_events when validating groups, for that case we + * need to ensure that cpuc->events[idx] is NULL so we don't use + * an uninitialized pointer. Conflicts for matrix events in groups + * are checked during event mapping anyway (see falkor_event_map). + */ + cpuc->events[idx] = NULL; + + return idx; +} + +/* + * Reset the PMU + */ +static void falkor_reset(void *info) +{ + struct arm_pmu *pmu = (struct arm_pmu *)info; + u32 i, ctrs = pmu->num_events; + + /* PMRESRx_EL0 regs are unknown at reset, except for the EN field */ + for (i = 0; i <= QC_MAX_RESR; i++) + falkor_write_pmresr(i, 0); + + /* PMXEVCNTCRx_EL0 regs are unknown at reset */ + for (i = 0; i <= ctrs; i++) { + write_sysreg(i, pmselr_el0); + isb(); + write_sysreg_s(0, pmxevcntcr_el0); + } + + /* Let the original op handle the rest */ + def_ops->reset(info); +} + +/* + * Enable the given event + */ +static void falkor_enable(struct perf_event *event) +{ + if (!!(event->attr.config & QC_EVT_PFX_MASK)) { + /* Matrix event, program the appropriate PMRESRx_EL0 */ + struct arm_pmu *pmu = to_arm_pmu(event->pmu); + struct pmu_hw_events *events = this_cpu_ptr(pmu->hw_events); + u64 reg = QC_EVT_REG(event->attr.config); + u64 code = QC_EVT_CODE(event->attr.config); + u64 group = QC_EVT_GROUP(event->attr.config); + unsigned long flags; + + raw_spin_lock_irqsave(&events->pmu_lock, flags); + falkor_set_resr(reg, group, code); + raw_spin_unlock_irqrestore(&events->pmu_lock, flags); + } + + /* Let the original op handle the rest */ + def_ops->enable(event); +} + +/* + * Disable the given event + */ +static void falkor_disable(struct perf_event *event) +{ + /* Use the original op to disable the counter and interrupt */ + def_ops->enable(event); + + if (!!(event->attr.config & QC_EVT_PFX_MASK)) { + /* Matrix event, de-program the appropriate PMRESRx_EL0 */ + struct arm_pmu *pmu = to_arm_pmu(event->pmu); + struct pmu_hw_events *events = this_cpu_ptr(pmu->hw_events); + u64 reg = QC_EVT_REG(event->attr.config); + u64 group = QC_EVT_GROUP(event->attr.config); + unsigned long flags; + + raw_spin_lock_irqsave(&events->pmu_lock, flags); + falkor_clear_resr(reg, group); + raw_spin_unlock_irqrestore(&events->pmu_lock, flags); + } +} + +PMU_FORMAT_ATTR(event, "config:0-15"); +PMU_FORMAT_ATTR(prefix, "config:16"); +PMU_FORMAT_ATTR(reg, "config:12-15"); +PMU_FORMAT_ATTR(code, "config:4-11"); +PMU_FORMAT_ATTR(group, "config:0-3"); + +static struct attribute *falkor_pmu_formats[] = { + &format_attr_event.attr, + &format_attr_prefix.attr, + &format_attr_reg.attr, + &format_attr_code.attr, + &format_attr_group.attr, + NULL, +}; + +static struct attribute_group falkor_pmu_format_attr_group = { + .name = "format", + .attrs = falkor_pmu_formats, +}; + +static int qcom_falkor_pmu_init(struct arm_pmu *pmu, struct device *dev) +{ + /* Save base arm_pmu so we can invoke its ops when appropriate */ + def_ops = devm_kmemdup(dev, pmu, sizeof(*def_ops), GFP_KERNEL); + if (!def_ops) { + pr_warn("Failed to allocate arm_pmu for QCOM extensions"); + return -ENODEV; + } + + pmu->name = "qcom_pmuv3"; + + /* Override the necessary ops */ + pmu->map_event = falkor_map_event; + pmu->get_event_idx = falkor_get_event_idx; + pmu->reset = falkor_reset; + pmu->enable = falkor_enable; + pmu->disable = falkor_disable; + + /* Override the necessary attributes */ + pmu->pmu.attr_groups[ARMPMU_ATTR_GROUP_FORMATS] = + &falkor_pmu_format_attr_group; + + return 1; +} + +ACPI_DECLARE_PMU_VARIANT(qcom_falkor, "QCOM8150", qcom_falkor_pmu_init); -- Qualcomm Datacenter Technologies, Inc. on behalf of the Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.
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