summaryrefslogtreecommitdiffstats
path: root/arch/x86/events/amd/iommu.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/events/amd/iommu.c')
-rw-r--r--arch/x86/events/amd/iommu.c489
1 files changed, 489 insertions, 0 deletions
diff --git a/arch/x86/events/amd/iommu.c b/arch/x86/events/amd/iommu.c
new file mode 100644
index 000000000..b15f7b950
--- /dev/null
+++ b/arch/x86/events/amd/iommu.c
@@ -0,0 +1,489 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2013 Advanced Micro Devices, Inc.
+ *
+ * Author: Steven Kinney <Steven.Kinney@amd.com>
+ * Author: Suravee Suthikulpanit <Suraveee.Suthikulpanit@amd.com>
+ *
+ * Perf: amd_iommu - AMD IOMMU Performance Counter PMU implementation
+ */
+
+#define pr_fmt(fmt) "perf/amd_iommu: " fmt
+
+#include <linux/perf_event.h>
+#include <linux/init.h>
+#include <linux/cpumask.h>
+#include <linux/slab.h>
+#include <linux/amd-iommu.h>
+
+#include "../perf_event.h"
+#include "iommu.h"
+
+/* iommu pmu conf masks */
+#define GET_CSOURCE(x) ((x)->conf & 0xFFULL)
+#define GET_DEVID(x) (((x)->conf >> 8) & 0xFFFFULL)
+#define GET_DOMID(x) (((x)->conf >> 24) & 0xFFFFULL)
+#define GET_PASID(x) (((x)->conf >> 40) & 0xFFFFFULL)
+
+/* iommu pmu conf1 masks */
+#define GET_DEVID_MASK(x) ((x)->conf1 & 0xFFFFULL)
+#define GET_DOMID_MASK(x) (((x)->conf1 >> 16) & 0xFFFFULL)
+#define GET_PASID_MASK(x) (((x)->conf1 >> 32) & 0xFFFFFULL)
+
+#define IOMMU_NAME_SIZE 16
+
+struct perf_amd_iommu {
+ struct list_head list;
+ struct pmu pmu;
+ struct amd_iommu *iommu;
+ char name[IOMMU_NAME_SIZE];
+ u8 max_banks;
+ u8 max_counters;
+ u64 cntr_assign_mask;
+ raw_spinlock_t lock;
+};
+
+static LIST_HEAD(perf_amd_iommu_list);
+
+/*---------------------------------------------
+ * sysfs format attributes
+ *---------------------------------------------*/
+PMU_FORMAT_ATTR(csource, "config:0-7");
+PMU_FORMAT_ATTR(devid, "config:8-23");
+PMU_FORMAT_ATTR(domid, "config:24-39");
+PMU_FORMAT_ATTR(pasid, "config:40-59");
+PMU_FORMAT_ATTR(devid_mask, "config1:0-15");
+PMU_FORMAT_ATTR(domid_mask, "config1:16-31");
+PMU_FORMAT_ATTR(pasid_mask, "config1:32-51");
+
+static struct attribute *iommu_format_attrs[] = {
+ &format_attr_csource.attr,
+ &format_attr_devid.attr,
+ &format_attr_pasid.attr,
+ &format_attr_domid.attr,
+ &format_attr_devid_mask.attr,
+ &format_attr_pasid_mask.attr,
+ &format_attr_domid_mask.attr,
+ NULL,
+};
+
+static struct attribute_group amd_iommu_format_group = {
+ .name = "format",
+ .attrs = iommu_format_attrs,
+};
+
+/*---------------------------------------------
+ * sysfs events attributes
+ *---------------------------------------------*/
+static struct attribute_group amd_iommu_events_group = {
+ .name = "events",
+};
+
+struct amd_iommu_event_desc {
+ struct device_attribute attr;
+ const char *event;
+};
+
+static ssize_t _iommu_event_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct amd_iommu_event_desc *event =
+ container_of(attr, struct amd_iommu_event_desc, attr);
+ return sprintf(buf, "%s\n", event->event);
+}
+
+#define AMD_IOMMU_EVENT_DESC(_name, _event) \
+{ \
+ .attr = __ATTR(_name, 0444, _iommu_event_show, NULL), \
+ .event = _event, \
+}
+
+static struct amd_iommu_event_desc amd_iommu_v2_event_descs[] = {
+ AMD_IOMMU_EVENT_DESC(mem_pass_untrans, "csource=0x01"),
+ AMD_IOMMU_EVENT_DESC(mem_pass_pretrans, "csource=0x02"),
+ AMD_IOMMU_EVENT_DESC(mem_pass_excl, "csource=0x03"),
+ AMD_IOMMU_EVENT_DESC(mem_target_abort, "csource=0x04"),
+ AMD_IOMMU_EVENT_DESC(mem_trans_total, "csource=0x05"),
+ AMD_IOMMU_EVENT_DESC(mem_iommu_tlb_pte_hit, "csource=0x06"),
+ AMD_IOMMU_EVENT_DESC(mem_iommu_tlb_pte_mis, "csource=0x07"),
+ AMD_IOMMU_EVENT_DESC(mem_iommu_tlb_pde_hit, "csource=0x08"),
+ AMD_IOMMU_EVENT_DESC(mem_iommu_tlb_pde_mis, "csource=0x09"),
+ AMD_IOMMU_EVENT_DESC(mem_dte_hit, "csource=0x0a"),
+ AMD_IOMMU_EVENT_DESC(mem_dte_mis, "csource=0x0b"),
+ AMD_IOMMU_EVENT_DESC(page_tbl_read_tot, "csource=0x0c"),
+ AMD_IOMMU_EVENT_DESC(page_tbl_read_nst, "csource=0x0d"),
+ AMD_IOMMU_EVENT_DESC(page_tbl_read_gst, "csource=0x0e"),
+ AMD_IOMMU_EVENT_DESC(int_dte_hit, "csource=0x0f"),
+ AMD_IOMMU_EVENT_DESC(int_dte_mis, "csource=0x10"),
+ AMD_IOMMU_EVENT_DESC(cmd_processed, "csource=0x11"),
+ AMD_IOMMU_EVENT_DESC(cmd_processed_inv, "csource=0x12"),
+ AMD_IOMMU_EVENT_DESC(tlb_inv, "csource=0x13"),
+ AMD_IOMMU_EVENT_DESC(ign_rd_wr_mmio_1ff8h, "csource=0x14"),
+ AMD_IOMMU_EVENT_DESC(vapic_int_non_guest, "csource=0x15"),
+ AMD_IOMMU_EVENT_DESC(vapic_int_guest, "csource=0x16"),
+ AMD_IOMMU_EVENT_DESC(smi_recv, "csource=0x17"),
+ AMD_IOMMU_EVENT_DESC(smi_blk, "csource=0x18"),
+ { /* end: all zeroes */ },
+};
+
+/*---------------------------------------------
+ * sysfs cpumask attributes
+ *---------------------------------------------*/
+static cpumask_t iommu_cpumask;
+
+static ssize_t _iommu_cpumask_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ return cpumap_print_to_pagebuf(true, buf, &iommu_cpumask);
+}
+static DEVICE_ATTR(cpumask, S_IRUGO, _iommu_cpumask_show, NULL);
+
+static struct attribute *iommu_cpumask_attrs[] = {
+ &dev_attr_cpumask.attr,
+ NULL,
+};
+
+static struct attribute_group amd_iommu_cpumask_group = {
+ .attrs = iommu_cpumask_attrs,
+};
+
+/*---------------------------------------------*/
+
+static int get_next_avail_iommu_bnk_cntr(struct perf_event *event)
+{
+ struct perf_amd_iommu *piommu = container_of(event->pmu, struct perf_amd_iommu, pmu);
+ int max_cntrs = piommu->max_counters;
+ int max_banks = piommu->max_banks;
+ u32 shift, bank, cntr;
+ unsigned long flags;
+ int retval;
+
+ raw_spin_lock_irqsave(&piommu->lock, flags);
+
+ for (bank = 0; bank < max_banks; bank++) {
+ for (cntr = 0; cntr < max_cntrs; cntr++) {
+ shift = bank + (bank*3) + cntr;
+ if (piommu->cntr_assign_mask & BIT_ULL(shift)) {
+ continue;
+ } else {
+ piommu->cntr_assign_mask |= BIT_ULL(shift);
+ event->hw.iommu_bank = bank;
+ event->hw.iommu_cntr = cntr;
+ retval = 0;
+ goto out;
+ }
+ }
+ }
+ retval = -ENOSPC;
+out:
+ raw_spin_unlock_irqrestore(&piommu->lock, flags);
+ return retval;
+}
+
+static int clear_avail_iommu_bnk_cntr(struct perf_amd_iommu *perf_iommu,
+ u8 bank, u8 cntr)
+{
+ unsigned long flags;
+ int max_banks, max_cntrs;
+ int shift = 0;
+
+ max_banks = perf_iommu->max_banks;
+ max_cntrs = perf_iommu->max_counters;
+
+ if ((bank > max_banks) || (cntr > max_cntrs))
+ return -EINVAL;
+
+ shift = bank + cntr + (bank*3);
+
+ raw_spin_lock_irqsave(&perf_iommu->lock, flags);
+ perf_iommu->cntr_assign_mask &= ~(1ULL<<shift);
+ raw_spin_unlock_irqrestore(&perf_iommu->lock, flags);
+
+ return 0;
+}
+
+static int perf_iommu_event_init(struct perf_event *event)
+{
+ struct hw_perf_event *hwc = &event->hw;
+
+ /* test the event attr type check for PMU enumeration */
+ if (event->attr.type != event->pmu->type)
+ return -ENOENT;
+
+ /*
+ * IOMMU counters are shared across all cores.
+ * Therefore, it does not support per-process mode.
+ * Also, it does not support event sampling mode.
+ */
+ if (is_sampling_event(event) || event->attach_state & PERF_ATTACH_TASK)
+ return -EINVAL;
+
+ if (event->cpu < 0)
+ return -EINVAL;
+
+ /* update the hw_perf_event struct with the iommu config data */
+ hwc->conf = event->attr.config;
+ hwc->conf1 = event->attr.config1;
+
+ return 0;
+}
+
+static inline struct amd_iommu *perf_event_2_iommu(struct perf_event *ev)
+{
+ return (container_of(ev->pmu, struct perf_amd_iommu, pmu))->iommu;
+}
+
+static void perf_iommu_enable_event(struct perf_event *ev)
+{
+ struct amd_iommu *iommu = perf_event_2_iommu(ev);
+ struct hw_perf_event *hwc = &ev->hw;
+ u8 bank = hwc->iommu_bank;
+ u8 cntr = hwc->iommu_cntr;
+ u64 reg = 0ULL;
+
+ reg = GET_CSOURCE(hwc);
+ amd_iommu_pc_set_reg(iommu, bank, cntr, IOMMU_PC_COUNTER_SRC_REG, &reg);
+
+ reg = GET_DEVID_MASK(hwc);
+ reg = GET_DEVID(hwc) | (reg << 32);
+ if (reg)
+ reg |= BIT(31);
+ amd_iommu_pc_set_reg(iommu, bank, cntr, IOMMU_PC_DEVID_MATCH_REG, &reg);
+
+ reg = GET_PASID_MASK(hwc);
+ reg = GET_PASID(hwc) | (reg << 32);
+ if (reg)
+ reg |= BIT(31);
+ amd_iommu_pc_set_reg(iommu, bank, cntr, IOMMU_PC_PASID_MATCH_REG, &reg);
+
+ reg = GET_DOMID_MASK(hwc);
+ reg = GET_DOMID(hwc) | (reg << 32);
+ if (reg)
+ reg |= BIT(31);
+ amd_iommu_pc_set_reg(iommu, bank, cntr, IOMMU_PC_DOMID_MATCH_REG, &reg);
+}
+
+static void perf_iommu_disable_event(struct perf_event *event)
+{
+ struct amd_iommu *iommu = perf_event_2_iommu(event);
+ struct hw_perf_event *hwc = &event->hw;
+ u64 reg = 0ULL;
+
+ amd_iommu_pc_set_reg(iommu, hwc->iommu_bank, hwc->iommu_cntr,
+ IOMMU_PC_COUNTER_SRC_REG, &reg);
+}
+
+static void perf_iommu_start(struct perf_event *event, int flags)
+{
+ struct hw_perf_event *hwc = &event->hw;
+
+ if (WARN_ON_ONCE(!(hwc->state & PERF_HES_STOPPED)))
+ return;
+
+ WARN_ON_ONCE(!(hwc->state & PERF_HES_UPTODATE));
+ hwc->state = 0;
+
+ /*
+ * To account for power-gating, which prevents write to
+ * the counter, we need to enable the counter
+ * before setting up counter register.
+ */
+ perf_iommu_enable_event(event);
+
+ if (flags & PERF_EF_RELOAD) {
+ u64 count = 0;
+ struct amd_iommu *iommu = perf_event_2_iommu(event);
+
+ /*
+ * Since the IOMMU PMU only support counting mode,
+ * the counter always start with value zero.
+ */
+ amd_iommu_pc_set_reg(iommu, hwc->iommu_bank, hwc->iommu_cntr,
+ IOMMU_PC_COUNTER_REG, &count);
+ }
+
+ perf_event_update_userpage(event);
+}
+
+static void perf_iommu_read(struct perf_event *event)
+{
+ u64 count;
+ struct hw_perf_event *hwc = &event->hw;
+ struct amd_iommu *iommu = perf_event_2_iommu(event);
+
+ if (amd_iommu_pc_get_reg(iommu, hwc->iommu_bank, hwc->iommu_cntr,
+ IOMMU_PC_COUNTER_REG, &count))
+ return;
+
+ /* IOMMU pc counter register is only 48 bits */
+ count &= GENMASK_ULL(47, 0);
+
+ /*
+ * Since the counter always start with value zero,
+ * simply just accumulate the count for the event.
+ */
+ local64_add(count, &event->count);
+}
+
+static void perf_iommu_stop(struct perf_event *event, int flags)
+{
+ struct hw_perf_event *hwc = &event->hw;
+
+ if (hwc->state & PERF_HES_UPTODATE)
+ return;
+
+ /*
+ * To account for power-gating, in which reading the counter would
+ * return zero, we need to read the register before disabling.
+ */
+ perf_iommu_read(event);
+ hwc->state |= PERF_HES_UPTODATE;
+
+ perf_iommu_disable_event(event);
+ WARN_ON_ONCE(hwc->state & PERF_HES_STOPPED);
+ hwc->state |= PERF_HES_STOPPED;
+}
+
+static int perf_iommu_add(struct perf_event *event, int flags)
+{
+ int retval;
+
+ event->hw.state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
+
+ /* request an iommu bank/counter */
+ retval = get_next_avail_iommu_bnk_cntr(event);
+ if (retval)
+ return retval;
+
+ if (flags & PERF_EF_START)
+ perf_iommu_start(event, PERF_EF_RELOAD);
+
+ return 0;
+}
+
+static void perf_iommu_del(struct perf_event *event, int flags)
+{
+ struct hw_perf_event *hwc = &event->hw;
+ struct perf_amd_iommu *perf_iommu =
+ container_of(event->pmu, struct perf_amd_iommu, pmu);
+
+ perf_iommu_stop(event, PERF_EF_UPDATE);
+
+ /* clear the assigned iommu bank/counter */
+ clear_avail_iommu_bnk_cntr(perf_iommu,
+ hwc->iommu_bank, hwc->iommu_cntr);
+
+ perf_event_update_userpage(event);
+}
+
+static __init int _init_events_attrs(void)
+{
+ int i = 0, j;
+ struct attribute **attrs;
+
+ while (amd_iommu_v2_event_descs[i].attr.attr.name)
+ i++;
+
+ attrs = kcalloc(i + 1, sizeof(*attrs), GFP_KERNEL);
+ if (!attrs)
+ return -ENOMEM;
+
+ for (j = 0; j < i; j++)
+ attrs[j] = &amd_iommu_v2_event_descs[j].attr.attr;
+
+ amd_iommu_events_group.attrs = attrs;
+ return 0;
+}
+
+static const struct attribute_group *amd_iommu_attr_groups[] = {
+ &amd_iommu_format_group,
+ &amd_iommu_cpumask_group,
+ &amd_iommu_events_group,
+ NULL,
+};
+
+static const struct pmu iommu_pmu __initconst = {
+ .event_init = perf_iommu_event_init,
+ .add = perf_iommu_add,
+ .del = perf_iommu_del,
+ .start = perf_iommu_start,
+ .stop = perf_iommu_stop,
+ .read = perf_iommu_read,
+ .task_ctx_nr = perf_invalid_context,
+ .attr_groups = amd_iommu_attr_groups,
+ .capabilities = PERF_PMU_CAP_NO_EXCLUDE,
+};
+
+static __init int init_one_iommu(unsigned int idx)
+{
+ struct perf_amd_iommu *perf_iommu;
+ int ret;
+
+ perf_iommu = kzalloc(sizeof(struct perf_amd_iommu), GFP_KERNEL);
+ if (!perf_iommu)
+ return -ENOMEM;
+
+ raw_spin_lock_init(&perf_iommu->lock);
+
+ perf_iommu->pmu = iommu_pmu;
+ perf_iommu->iommu = get_amd_iommu(idx);
+ perf_iommu->max_banks = amd_iommu_pc_get_max_banks(idx);
+ perf_iommu->max_counters = amd_iommu_pc_get_max_counters(idx);
+
+ if (!perf_iommu->iommu ||
+ !perf_iommu->max_banks ||
+ !perf_iommu->max_counters) {
+ kfree(perf_iommu);
+ return -EINVAL;
+ }
+
+ snprintf(perf_iommu->name, IOMMU_NAME_SIZE, "amd_iommu_%u", idx);
+
+ ret = perf_pmu_register(&perf_iommu->pmu, perf_iommu->name, -1);
+ if (!ret) {
+ pr_info("Detected AMD IOMMU #%d (%d banks, %d counters/bank).\n",
+ idx, perf_iommu->max_banks, perf_iommu->max_counters);
+ list_add_tail(&perf_iommu->list, &perf_amd_iommu_list);
+ } else {
+ pr_warn("Error initializing IOMMU %d.\n", idx);
+ kfree(perf_iommu);
+ }
+ return ret;
+}
+
+static __init int amd_iommu_pc_init(void)
+{
+ unsigned int i, cnt = 0;
+ int ret;
+
+ /* Make sure the IOMMU PC resource is available */
+ if (!amd_iommu_pc_supported())
+ return -ENODEV;
+
+ ret = _init_events_attrs();
+ if (ret)
+ return ret;
+
+ /*
+ * An IOMMU PMU is specific to an IOMMU, and can function independently.
+ * So we go through all IOMMUs and ignore the one that fails init
+ * unless all IOMMU are failing.
+ */
+ for (i = 0; i < amd_iommu_get_num_iommus(); i++) {
+ ret = init_one_iommu(i);
+ if (!ret)
+ cnt++;
+ }
+
+ if (!cnt) {
+ kfree(amd_iommu_events_group.attrs);
+ return -ENODEV;
+ }
+
+ /* Init cpumask attributes to only core 0 */
+ cpumask_set_cpu(0, &iommu_cpumask);
+ return 0;
+}
+
+device_initcall(amd_iommu_pc_init);