cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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qcom_l2_pmu.c (26823B)


      1// SPDX-License-Identifier: GPL-2.0-only
      2/* Copyright (c) 2015-2017 The Linux Foundation. All rights reserved.
      3 */
      4#include <linux/acpi.h>
      5#include <linux/bitops.h>
      6#include <linux/bug.h>
      7#include <linux/cpuhotplug.h>
      8#include <linux/cpumask.h>
      9#include <linux/device.h>
     10#include <linux/errno.h>
     11#include <linux/interrupt.h>
     12#include <linux/irq.h>
     13#include <linux/kernel.h>
     14#include <linux/list.h>
     15#include <linux/percpu.h>
     16#include <linux/perf_event.h>
     17#include <linux/platform_device.h>
     18#include <linux/smp.h>
     19#include <linux/spinlock.h>
     20#include <linux/sysfs.h>
     21#include <linux/types.h>
     22
     23#include <asm/barrier.h>
     24#include <asm/local64.h>
     25#include <asm/sysreg.h>
     26#include <soc/qcom/kryo-l2-accessors.h>
     27
     28#define MAX_L2_CTRS             9
     29
     30#define L2PMCR_NUM_EV_SHIFT     11
     31#define L2PMCR_NUM_EV_MASK      0x1F
     32
     33#define L2PMCR                  0x400
     34#define L2PMCNTENCLR            0x403
     35#define L2PMCNTENSET            0x404
     36#define L2PMINTENCLR            0x405
     37#define L2PMINTENSET            0x406
     38#define L2PMOVSCLR              0x407
     39#define L2PMOVSSET              0x408
     40#define L2PMCCNTCR              0x409
     41#define L2PMCCNTR               0x40A
     42#define L2PMCCNTSR              0x40C
     43#define L2PMRESR                0x410
     44#define IA_L2PMXEVCNTCR_BASE    0x420
     45#define IA_L2PMXEVCNTR_BASE     0x421
     46#define IA_L2PMXEVFILTER_BASE   0x423
     47#define IA_L2PMXEVTYPER_BASE    0x424
     48
     49#define IA_L2_REG_OFFSET        0x10
     50
     51#define L2PMXEVFILTER_SUFILTER_ALL      0x000E0000
     52#define L2PMXEVFILTER_ORGFILTER_IDINDEP 0x00000004
     53#define L2PMXEVFILTER_ORGFILTER_ALL     0x00000003
     54
     55#define L2EVTYPER_REG_SHIFT     3
     56
     57#define L2PMRESR_GROUP_BITS     8
     58#define L2PMRESR_GROUP_MASK     GENMASK(7, 0)
     59
     60#define L2CYCLE_CTR_BIT         31
     61#define L2CYCLE_CTR_RAW_CODE    0xFE
     62
     63#define L2PMCR_RESET_ALL        0x6
     64#define L2PMCR_COUNTERS_ENABLE  0x1
     65#define L2PMCR_COUNTERS_DISABLE 0x0
     66
     67#define L2PMRESR_EN             BIT_ULL(63)
     68
     69#define L2_EVT_MASK             0x00000FFF
     70#define L2_EVT_CODE_MASK        0x00000FF0
     71#define L2_EVT_GRP_MASK         0x0000000F
     72#define L2_EVT_CODE_SHIFT       4
     73#define L2_EVT_GRP_SHIFT        0
     74
     75#define L2_EVT_CODE(event)   (((event) & L2_EVT_CODE_MASK) >> L2_EVT_CODE_SHIFT)
     76#define L2_EVT_GROUP(event)  (((event) & L2_EVT_GRP_MASK) >> L2_EVT_GRP_SHIFT)
     77
     78#define L2_EVT_GROUP_MAX        7
     79
     80#define L2_COUNTER_RELOAD       BIT_ULL(31)
     81#define L2_CYCLE_COUNTER_RELOAD BIT_ULL(63)
     82
     83
     84#define reg_idx(reg, i)         (((i) * IA_L2_REG_OFFSET) + reg##_BASE)
     85
     86/*
     87 * Events
     88 */
     89#define L2_EVENT_CYCLES                    0xfe
     90#define L2_EVENT_DCACHE_OPS                0x400
     91#define L2_EVENT_ICACHE_OPS                0x401
     92#define L2_EVENT_TLBI                      0x402
     93#define L2_EVENT_BARRIERS                  0x403
     94#define L2_EVENT_TOTAL_READS               0x405
     95#define L2_EVENT_TOTAL_WRITES              0x406
     96#define L2_EVENT_TOTAL_REQUESTS            0x407
     97#define L2_EVENT_LDREX                     0x420
     98#define L2_EVENT_STREX                     0x421
     99#define L2_EVENT_CLREX                     0x422
    100
    101
    102
    103struct cluster_pmu;
    104
    105/*
    106 * Aggregate PMU. Implements the core pmu functions and manages
    107 * the hardware PMUs.
    108 */
    109struct l2cache_pmu {
    110	struct hlist_node node;
    111	u32 num_pmus;
    112	struct pmu pmu;
    113	int num_counters;
    114	cpumask_t cpumask;
    115	struct platform_device *pdev;
    116	struct cluster_pmu * __percpu *pmu_cluster;
    117	struct list_head clusters;
    118};
    119
    120/*
    121 * The cache is made up of one or more clusters, each cluster has its own PMU.
    122 * Each cluster is associated with one or more CPUs.
    123 * This structure represents one of the hardware PMUs.
    124 *
    125 * Events can be envisioned as a 2-dimensional array. Each column represents
    126 * a group of events. There are 8 groups. Only one entry from each
    127 * group can be in use at a time.
    128 *
    129 * Events are specified as 0xCCG, where CC is 2 hex digits specifying
    130 * the code (array row) and G specifies the group (column).
    131 *
    132 * In addition there is a cycle counter event specified by L2CYCLE_CTR_RAW_CODE
    133 * which is outside the above scheme.
    134 */
    135struct cluster_pmu {
    136	struct list_head next;
    137	struct perf_event *events[MAX_L2_CTRS];
    138	struct l2cache_pmu *l2cache_pmu;
    139	DECLARE_BITMAP(used_counters, MAX_L2_CTRS);
    140	DECLARE_BITMAP(used_groups, L2_EVT_GROUP_MAX + 1);
    141	int irq;
    142	int cluster_id;
    143	/* The CPU that is used for collecting events on this cluster */
    144	int on_cpu;
    145	/* All the CPUs associated with this cluster */
    146	cpumask_t cluster_cpus;
    147	spinlock_t pmu_lock;
    148};
    149
    150#define to_l2cache_pmu(p) (container_of(p, struct l2cache_pmu, pmu))
    151
    152static u32 l2_cycle_ctr_idx;
    153static u32 l2_counter_present_mask;
    154
    155static inline u32 idx_to_reg_bit(u32 idx)
    156{
    157	if (idx == l2_cycle_ctr_idx)
    158		return BIT(L2CYCLE_CTR_BIT);
    159
    160	return BIT(idx);
    161}
    162
    163static inline struct cluster_pmu *get_cluster_pmu(
    164	struct l2cache_pmu *l2cache_pmu, int cpu)
    165{
    166	return *per_cpu_ptr(l2cache_pmu->pmu_cluster, cpu);
    167}
    168
    169static void cluster_pmu_reset(void)
    170{
    171	/* Reset all counters */
    172	kryo_l2_set_indirect_reg(L2PMCR, L2PMCR_RESET_ALL);
    173	kryo_l2_set_indirect_reg(L2PMCNTENCLR, l2_counter_present_mask);
    174	kryo_l2_set_indirect_reg(L2PMINTENCLR, l2_counter_present_mask);
    175	kryo_l2_set_indirect_reg(L2PMOVSCLR, l2_counter_present_mask);
    176}
    177
    178static inline void cluster_pmu_enable(void)
    179{
    180	kryo_l2_set_indirect_reg(L2PMCR, L2PMCR_COUNTERS_ENABLE);
    181}
    182
    183static inline void cluster_pmu_disable(void)
    184{
    185	kryo_l2_set_indirect_reg(L2PMCR, L2PMCR_COUNTERS_DISABLE);
    186}
    187
    188static inline void cluster_pmu_counter_set_value(u32 idx, u64 value)
    189{
    190	if (idx == l2_cycle_ctr_idx)
    191		kryo_l2_set_indirect_reg(L2PMCCNTR, value);
    192	else
    193		kryo_l2_set_indirect_reg(reg_idx(IA_L2PMXEVCNTR, idx), value);
    194}
    195
    196static inline u64 cluster_pmu_counter_get_value(u32 idx)
    197{
    198	u64 value;
    199
    200	if (idx == l2_cycle_ctr_idx)
    201		value = kryo_l2_get_indirect_reg(L2PMCCNTR);
    202	else
    203		value = kryo_l2_get_indirect_reg(reg_idx(IA_L2PMXEVCNTR, idx));
    204
    205	return value;
    206}
    207
    208static inline void cluster_pmu_counter_enable(u32 idx)
    209{
    210	kryo_l2_set_indirect_reg(L2PMCNTENSET, idx_to_reg_bit(idx));
    211}
    212
    213static inline void cluster_pmu_counter_disable(u32 idx)
    214{
    215	kryo_l2_set_indirect_reg(L2PMCNTENCLR, idx_to_reg_bit(idx));
    216}
    217
    218static inline void cluster_pmu_counter_enable_interrupt(u32 idx)
    219{
    220	kryo_l2_set_indirect_reg(L2PMINTENSET, idx_to_reg_bit(idx));
    221}
    222
    223static inline void cluster_pmu_counter_disable_interrupt(u32 idx)
    224{
    225	kryo_l2_set_indirect_reg(L2PMINTENCLR, idx_to_reg_bit(idx));
    226}
    227
    228static inline void cluster_pmu_set_evccntcr(u32 val)
    229{
    230	kryo_l2_set_indirect_reg(L2PMCCNTCR, val);
    231}
    232
    233static inline void cluster_pmu_set_evcntcr(u32 ctr, u32 val)
    234{
    235	kryo_l2_set_indirect_reg(reg_idx(IA_L2PMXEVCNTCR, ctr), val);
    236}
    237
    238static inline void cluster_pmu_set_evtyper(u32 ctr, u32 val)
    239{
    240	kryo_l2_set_indirect_reg(reg_idx(IA_L2PMXEVTYPER, ctr), val);
    241}
    242
    243static void cluster_pmu_set_resr(struct cluster_pmu *cluster,
    244			       u32 event_group, u32 event_cc)
    245{
    246	u64 field;
    247	u64 resr_val;
    248	u32 shift;
    249	unsigned long flags;
    250
    251	shift = L2PMRESR_GROUP_BITS * event_group;
    252	field = ((u64)(event_cc & L2PMRESR_GROUP_MASK) << shift);
    253
    254	spin_lock_irqsave(&cluster->pmu_lock, flags);
    255
    256	resr_val = kryo_l2_get_indirect_reg(L2PMRESR);
    257	resr_val &= ~(L2PMRESR_GROUP_MASK << shift);
    258	resr_val |= field;
    259	resr_val |= L2PMRESR_EN;
    260	kryo_l2_set_indirect_reg(L2PMRESR, resr_val);
    261
    262	spin_unlock_irqrestore(&cluster->pmu_lock, flags);
    263}
    264
    265/*
    266 * Hardware allows filtering of events based on the originating
    267 * CPU. Turn this off by setting filter bits to allow events from
    268 * all CPUS, subunits and ID independent events in this cluster.
    269 */
    270static inline void cluster_pmu_set_evfilter_sys_mode(u32 ctr)
    271{
    272	u32 val =  L2PMXEVFILTER_SUFILTER_ALL |
    273		   L2PMXEVFILTER_ORGFILTER_IDINDEP |
    274		   L2PMXEVFILTER_ORGFILTER_ALL;
    275
    276	kryo_l2_set_indirect_reg(reg_idx(IA_L2PMXEVFILTER, ctr), val);
    277}
    278
    279static inline u32 cluster_pmu_getreset_ovsr(void)
    280{
    281	u32 result = kryo_l2_get_indirect_reg(L2PMOVSSET);
    282
    283	kryo_l2_set_indirect_reg(L2PMOVSCLR, result);
    284	return result;
    285}
    286
    287static inline bool cluster_pmu_has_overflowed(u32 ovsr)
    288{
    289	return !!(ovsr & l2_counter_present_mask);
    290}
    291
    292static inline bool cluster_pmu_counter_has_overflowed(u32 ovsr, u32 idx)
    293{
    294	return !!(ovsr & idx_to_reg_bit(idx));
    295}
    296
    297static void l2_cache_event_update(struct perf_event *event)
    298{
    299	struct hw_perf_event *hwc = &event->hw;
    300	u64 delta, prev, now;
    301	u32 idx = hwc->idx;
    302
    303	do {
    304		prev = local64_read(&hwc->prev_count);
    305		now = cluster_pmu_counter_get_value(idx);
    306	} while (local64_cmpxchg(&hwc->prev_count, prev, now) != prev);
    307
    308	/*
    309	 * The cycle counter is 64-bit, but all other counters are
    310	 * 32-bit, and we must handle 32-bit overflow explicitly.
    311	 */
    312	delta = now - prev;
    313	if (idx != l2_cycle_ctr_idx)
    314		delta &= 0xffffffff;
    315
    316	local64_add(delta, &event->count);
    317}
    318
    319static void l2_cache_cluster_set_period(struct cluster_pmu *cluster,
    320				       struct hw_perf_event *hwc)
    321{
    322	u32 idx = hwc->idx;
    323	u64 new;
    324
    325	/*
    326	 * We limit the max period to half the max counter value so
    327	 * that even in the case of extreme interrupt latency the
    328	 * counter will (hopefully) not wrap past its initial value.
    329	 */
    330	if (idx == l2_cycle_ctr_idx)
    331		new = L2_CYCLE_COUNTER_RELOAD;
    332	else
    333		new = L2_COUNTER_RELOAD;
    334
    335	local64_set(&hwc->prev_count, new);
    336	cluster_pmu_counter_set_value(idx, new);
    337}
    338
    339static int l2_cache_get_event_idx(struct cluster_pmu *cluster,
    340				   struct perf_event *event)
    341{
    342	struct hw_perf_event *hwc = &event->hw;
    343	int idx;
    344	int num_ctrs = cluster->l2cache_pmu->num_counters - 1;
    345	unsigned int group;
    346
    347	if (hwc->config_base == L2CYCLE_CTR_RAW_CODE) {
    348		if (test_and_set_bit(l2_cycle_ctr_idx, cluster->used_counters))
    349			return -EAGAIN;
    350
    351		return l2_cycle_ctr_idx;
    352	}
    353
    354	idx = find_first_zero_bit(cluster->used_counters, num_ctrs);
    355	if (idx == num_ctrs)
    356		/* The counters are all in use. */
    357		return -EAGAIN;
    358
    359	/*
    360	 * Check for column exclusion: event column already in use by another
    361	 * event. This is for events which are not in the same group.
    362	 * Conflicting events in the same group are detected in event_init.
    363	 */
    364	group = L2_EVT_GROUP(hwc->config_base);
    365	if (test_bit(group, cluster->used_groups))
    366		return -EAGAIN;
    367
    368	set_bit(idx, cluster->used_counters);
    369	set_bit(group, cluster->used_groups);
    370
    371	return idx;
    372}
    373
    374static void l2_cache_clear_event_idx(struct cluster_pmu *cluster,
    375				      struct perf_event *event)
    376{
    377	struct hw_perf_event *hwc = &event->hw;
    378	int idx = hwc->idx;
    379
    380	clear_bit(idx, cluster->used_counters);
    381	if (hwc->config_base != L2CYCLE_CTR_RAW_CODE)
    382		clear_bit(L2_EVT_GROUP(hwc->config_base), cluster->used_groups);
    383}
    384
    385static irqreturn_t l2_cache_handle_irq(int irq_num, void *data)
    386{
    387	struct cluster_pmu *cluster = data;
    388	int num_counters = cluster->l2cache_pmu->num_counters;
    389	u32 ovsr;
    390	int idx;
    391
    392	ovsr = cluster_pmu_getreset_ovsr();
    393	if (!cluster_pmu_has_overflowed(ovsr))
    394		return IRQ_NONE;
    395
    396	for_each_set_bit(idx, cluster->used_counters, num_counters) {
    397		struct perf_event *event = cluster->events[idx];
    398		struct hw_perf_event *hwc;
    399
    400		if (WARN_ON_ONCE(!event))
    401			continue;
    402
    403		if (!cluster_pmu_counter_has_overflowed(ovsr, idx))
    404			continue;
    405
    406		l2_cache_event_update(event);
    407		hwc = &event->hw;
    408
    409		l2_cache_cluster_set_period(cluster, hwc);
    410	}
    411
    412	return IRQ_HANDLED;
    413}
    414
    415/*
    416 * Implementation of abstract pmu functionality required by
    417 * the core perf events code.
    418 */
    419
    420static void l2_cache_pmu_enable(struct pmu *pmu)
    421{
    422	/*
    423	 * Although there is only one PMU (per socket) controlling multiple
    424	 * physical PMUs (per cluster), because we do not support per-task mode
    425	 * each event is associated with a CPU. Each event has pmu_enable
    426	 * called on its CPU, so here it is only necessary to enable the
    427	 * counters for the current CPU.
    428	 */
    429
    430	cluster_pmu_enable();
    431}
    432
    433static void l2_cache_pmu_disable(struct pmu *pmu)
    434{
    435	cluster_pmu_disable();
    436}
    437
    438static int l2_cache_event_init(struct perf_event *event)
    439{
    440	struct hw_perf_event *hwc = &event->hw;
    441	struct cluster_pmu *cluster;
    442	struct perf_event *sibling;
    443	struct l2cache_pmu *l2cache_pmu;
    444
    445	if (event->attr.type != event->pmu->type)
    446		return -ENOENT;
    447
    448	l2cache_pmu = to_l2cache_pmu(event->pmu);
    449
    450	if (hwc->sample_period) {
    451		dev_dbg_ratelimited(&l2cache_pmu->pdev->dev,
    452				    "Sampling not supported\n");
    453		return -EOPNOTSUPP;
    454	}
    455
    456	if (event->cpu < 0) {
    457		dev_dbg_ratelimited(&l2cache_pmu->pdev->dev,
    458				    "Per-task mode not supported\n");
    459		return -EOPNOTSUPP;
    460	}
    461
    462	if (((L2_EVT_GROUP(event->attr.config) > L2_EVT_GROUP_MAX) ||
    463	     ((event->attr.config & ~L2_EVT_MASK) != 0)) &&
    464	    (event->attr.config != L2CYCLE_CTR_RAW_CODE)) {
    465		dev_dbg_ratelimited(&l2cache_pmu->pdev->dev,
    466				    "Invalid config %llx\n",
    467				    event->attr.config);
    468		return -EINVAL;
    469	}
    470
    471	/* Don't allow groups with mixed PMUs, except for s/w events */
    472	if (event->group_leader->pmu != event->pmu &&
    473	    !is_software_event(event->group_leader)) {
    474		dev_dbg_ratelimited(&l2cache_pmu->pdev->dev,
    475			 "Can't create mixed PMU group\n");
    476		return -EINVAL;
    477	}
    478
    479	for_each_sibling_event(sibling, event->group_leader) {
    480		if (sibling->pmu != event->pmu &&
    481		    !is_software_event(sibling)) {
    482			dev_dbg_ratelimited(&l2cache_pmu->pdev->dev,
    483				 "Can't create mixed PMU group\n");
    484			return -EINVAL;
    485		}
    486	}
    487
    488	cluster = get_cluster_pmu(l2cache_pmu, event->cpu);
    489	if (!cluster) {
    490		/* CPU has not been initialised */
    491		dev_dbg_ratelimited(&l2cache_pmu->pdev->dev,
    492			"CPU%d not associated with L2 cluster\n", event->cpu);
    493		return -EINVAL;
    494	}
    495
    496	/* Ensure all events in a group are on the same cpu */
    497	if ((event->group_leader != event) &&
    498	    (cluster->on_cpu != event->group_leader->cpu)) {
    499		dev_dbg_ratelimited(&l2cache_pmu->pdev->dev,
    500			 "Can't create group on CPUs %d and %d",
    501			 event->cpu, event->group_leader->cpu);
    502		return -EINVAL;
    503	}
    504
    505	if ((event != event->group_leader) &&
    506	    !is_software_event(event->group_leader) &&
    507	    (L2_EVT_GROUP(event->group_leader->attr.config) ==
    508	     L2_EVT_GROUP(event->attr.config))) {
    509		dev_dbg_ratelimited(&l2cache_pmu->pdev->dev,
    510			 "Column exclusion: conflicting events %llx %llx\n",
    511		       event->group_leader->attr.config,
    512		       event->attr.config);
    513		return -EINVAL;
    514	}
    515
    516	for_each_sibling_event(sibling, event->group_leader) {
    517		if ((sibling != event) &&
    518		    !is_software_event(sibling) &&
    519		    (L2_EVT_GROUP(sibling->attr.config) ==
    520		     L2_EVT_GROUP(event->attr.config))) {
    521			dev_dbg_ratelimited(&l2cache_pmu->pdev->dev,
    522			     "Column exclusion: conflicting events %llx %llx\n",
    523					    sibling->attr.config,
    524					    event->attr.config);
    525			return -EINVAL;
    526		}
    527	}
    528
    529	hwc->idx = -1;
    530	hwc->config_base = event->attr.config;
    531
    532	/*
    533	 * Ensure all events are on the same cpu so all events are in the
    534	 * same cpu context, to avoid races on pmu_enable etc.
    535	 */
    536	event->cpu = cluster->on_cpu;
    537
    538	return 0;
    539}
    540
    541static void l2_cache_event_start(struct perf_event *event, int flags)
    542{
    543	struct cluster_pmu *cluster;
    544	struct hw_perf_event *hwc = &event->hw;
    545	int idx = hwc->idx;
    546	u32 config;
    547	u32 event_cc, event_group;
    548
    549	hwc->state = 0;
    550
    551	cluster = get_cluster_pmu(to_l2cache_pmu(event->pmu), event->cpu);
    552
    553	l2_cache_cluster_set_period(cluster, hwc);
    554
    555	if (hwc->config_base == L2CYCLE_CTR_RAW_CODE) {
    556		cluster_pmu_set_evccntcr(0);
    557	} else {
    558		config = hwc->config_base;
    559		event_cc    = L2_EVT_CODE(config);
    560		event_group = L2_EVT_GROUP(config);
    561
    562		cluster_pmu_set_evcntcr(idx, 0);
    563		cluster_pmu_set_evtyper(idx, event_group);
    564		cluster_pmu_set_resr(cluster, event_group, event_cc);
    565		cluster_pmu_set_evfilter_sys_mode(idx);
    566	}
    567
    568	cluster_pmu_counter_enable_interrupt(idx);
    569	cluster_pmu_counter_enable(idx);
    570}
    571
    572static void l2_cache_event_stop(struct perf_event *event, int flags)
    573{
    574	struct hw_perf_event *hwc = &event->hw;
    575	int idx = hwc->idx;
    576
    577	if (hwc->state & PERF_HES_STOPPED)
    578		return;
    579
    580	cluster_pmu_counter_disable_interrupt(idx);
    581	cluster_pmu_counter_disable(idx);
    582
    583	if (flags & PERF_EF_UPDATE)
    584		l2_cache_event_update(event);
    585	hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE;
    586}
    587
    588static int l2_cache_event_add(struct perf_event *event, int flags)
    589{
    590	struct hw_perf_event *hwc = &event->hw;
    591	int idx;
    592	int err = 0;
    593	struct cluster_pmu *cluster;
    594
    595	cluster = get_cluster_pmu(to_l2cache_pmu(event->pmu), event->cpu);
    596
    597	idx = l2_cache_get_event_idx(cluster, event);
    598	if (idx < 0)
    599		return idx;
    600
    601	hwc->idx = idx;
    602	hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
    603	cluster->events[idx] = event;
    604	local64_set(&hwc->prev_count, 0);
    605
    606	if (flags & PERF_EF_START)
    607		l2_cache_event_start(event, flags);
    608
    609	/* Propagate changes to the userspace mapping. */
    610	perf_event_update_userpage(event);
    611
    612	return err;
    613}
    614
    615static void l2_cache_event_del(struct perf_event *event, int flags)
    616{
    617	struct hw_perf_event *hwc = &event->hw;
    618	struct cluster_pmu *cluster;
    619	int idx = hwc->idx;
    620
    621	cluster = get_cluster_pmu(to_l2cache_pmu(event->pmu), event->cpu);
    622
    623	l2_cache_event_stop(event, flags | PERF_EF_UPDATE);
    624	cluster->events[idx] = NULL;
    625	l2_cache_clear_event_idx(cluster, event);
    626
    627	perf_event_update_userpage(event);
    628}
    629
    630static void l2_cache_event_read(struct perf_event *event)
    631{
    632	l2_cache_event_update(event);
    633}
    634
    635static ssize_t l2_cache_pmu_cpumask_show(struct device *dev,
    636					 struct device_attribute *attr,
    637					 char *buf)
    638{
    639	struct l2cache_pmu *l2cache_pmu = to_l2cache_pmu(dev_get_drvdata(dev));
    640
    641	return cpumap_print_to_pagebuf(true, buf, &l2cache_pmu->cpumask);
    642}
    643
    644static struct device_attribute l2_cache_pmu_cpumask_attr =
    645		__ATTR(cpumask, S_IRUGO, l2_cache_pmu_cpumask_show, NULL);
    646
    647static struct attribute *l2_cache_pmu_cpumask_attrs[] = {
    648	&l2_cache_pmu_cpumask_attr.attr,
    649	NULL,
    650};
    651
    652static const struct attribute_group l2_cache_pmu_cpumask_group = {
    653	.attrs = l2_cache_pmu_cpumask_attrs,
    654};
    655
    656/* CCG format for perf RAW codes. */
    657PMU_FORMAT_ATTR(l2_code,   "config:4-11");
    658PMU_FORMAT_ATTR(l2_group,  "config:0-3");
    659PMU_FORMAT_ATTR(event,     "config:0-11");
    660
    661static struct attribute *l2_cache_pmu_formats[] = {
    662	&format_attr_l2_code.attr,
    663	&format_attr_l2_group.attr,
    664	&format_attr_event.attr,
    665	NULL,
    666};
    667
    668static const struct attribute_group l2_cache_pmu_format_group = {
    669	.name = "format",
    670	.attrs = l2_cache_pmu_formats,
    671};
    672
    673static ssize_t l2cache_pmu_event_show(struct device *dev,
    674				      struct device_attribute *attr, char *page)
    675{
    676	struct perf_pmu_events_attr *pmu_attr;
    677
    678	pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr);
    679	return sysfs_emit(page, "event=0x%02llx\n", pmu_attr->id);
    680}
    681
    682#define L2CACHE_EVENT_ATTR(_name, _id)			    \
    683	PMU_EVENT_ATTR_ID(_name, l2cache_pmu_event_show, _id)
    684
    685static struct attribute *l2_cache_pmu_events[] = {
    686	L2CACHE_EVENT_ATTR(cycles, L2_EVENT_CYCLES),
    687	L2CACHE_EVENT_ATTR(dcache-ops, L2_EVENT_DCACHE_OPS),
    688	L2CACHE_EVENT_ATTR(icache-ops, L2_EVENT_ICACHE_OPS),
    689	L2CACHE_EVENT_ATTR(tlbi, L2_EVENT_TLBI),
    690	L2CACHE_EVENT_ATTR(barriers, L2_EVENT_BARRIERS),
    691	L2CACHE_EVENT_ATTR(total-reads, L2_EVENT_TOTAL_READS),
    692	L2CACHE_EVENT_ATTR(total-writes, L2_EVENT_TOTAL_WRITES),
    693	L2CACHE_EVENT_ATTR(total-requests, L2_EVENT_TOTAL_REQUESTS),
    694	L2CACHE_EVENT_ATTR(ldrex, L2_EVENT_LDREX),
    695	L2CACHE_EVENT_ATTR(strex, L2_EVENT_STREX),
    696	L2CACHE_EVENT_ATTR(clrex, L2_EVENT_CLREX),
    697	NULL
    698};
    699
    700static const struct attribute_group l2_cache_pmu_events_group = {
    701	.name = "events",
    702	.attrs = l2_cache_pmu_events,
    703};
    704
    705static const struct attribute_group *l2_cache_pmu_attr_grps[] = {
    706	&l2_cache_pmu_format_group,
    707	&l2_cache_pmu_cpumask_group,
    708	&l2_cache_pmu_events_group,
    709	NULL,
    710};
    711
    712/*
    713 * Generic device handlers
    714 */
    715
    716static const struct acpi_device_id l2_cache_pmu_acpi_match[] = {
    717	{ "QCOM8130", },
    718	{ }
    719};
    720
    721static int get_num_counters(void)
    722{
    723	int val;
    724
    725	val = kryo_l2_get_indirect_reg(L2PMCR);
    726
    727	/*
    728	 * Read number of counters from L2PMCR and add 1
    729	 * for the cycle counter.
    730	 */
    731	return ((val >> L2PMCR_NUM_EV_SHIFT) & L2PMCR_NUM_EV_MASK) + 1;
    732}
    733
    734static struct cluster_pmu *l2_cache_associate_cpu_with_cluster(
    735	struct l2cache_pmu *l2cache_pmu, int cpu)
    736{
    737	u64 mpidr;
    738	int cpu_cluster_id;
    739	struct cluster_pmu *cluster;
    740
    741	/*
    742	 * This assumes that the cluster_id is in MPIDR[aff1] for
    743	 * single-threaded cores, and MPIDR[aff2] for multi-threaded
    744	 * cores. This logic will have to be updated if this changes.
    745	 */
    746	mpidr = read_cpuid_mpidr();
    747	if (mpidr & MPIDR_MT_BITMASK)
    748		cpu_cluster_id = MPIDR_AFFINITY_LEVEL(mpidr, 2);
    749	else
    750		cpu_cluster_id = MPIDR_AFFINITY_LEVEL(mpidr, 1);
    751
    752	list_for_each_entry(cluster, &l2cache_pmu->clusters, next) {
    753		if (cluster->cluster_id != cpu_cluster_id)
    754			continue;
    755
    756		dev_info(&l2cache_pmu->pdev->dev,
    757			 "CPU%d associated with cluster %d\n", cpu,
    758			 cluster->cluster_id);
    759		cpumask_set_cpu(cpu, &cluster->cluster_cpus);
    760		*per_cpu_ptr(l2cache_pmu->pmu_cluster, cpu) = cluster;
    761		return cluster;
    762	}
    763
    764	return NULL;
    765}
    766
    767static int l2cache_pmu_online_cpu(unsigned int cpu, struct hlist_node *node)
    768{
    769	struct cluster_pmu *cluster;
    770	struct l2cache_pmu *l2cache_pmu;
    771
    772	l2cache_pmu = hlist_entry_safe(node, struct l2cache_pmu, node);
    773	cluster = get_cluster_pmu(l2cache_pmu, cpu);
    774	if (!cluster) {
    775		/* First time this CPU has come online */
    776		cluster = l2_cache_associate_cpu_with_cluster(l2cache_pmu, cpu);
    777		if (!cluster) {
    778			/* Only if broken firmware doesn't list every cluster */
    779			WARN_ONCE(1, "No L2 cache cluster for CPU%d\n", cpu);
    780			return 0;
    781		}
    782	}
    783
    784	/* If another CPU is managing this cluster, we're done */
    785	if (cluster->on_cpu != -1)
    786		return 0;
    787
    788	/*
    789	 * All CPUs on this cluster were down, use this one.
    790	 * Reset to put it into sane state.
    791	 */
    792	cluster->on_cpu = cpu;
    793	cpumask_set_cpu(cpu, &l2cache_pmu->cpumask);
    794	cluster_pmu_reset();
    795
    796	WARN_ON(irq_set_affinity(cluster->irq, cpumask_of(cpu)));
    797	enable_irq(cluster->irq);
    798
    799	return 0;
    800}
    801
    802static int l2cache_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
    803{
    804	struct cluster_pmu *cluster;
    805	struct l2cache_pmu *l2cache_pmu;
    806	cpumask_t cluster_online_cpus;
    807	unsigned int target;
    808
    809	l2cache_pmu = hlist_entry_safe(node, struct l2cache_pmu, node);
    810	cluster = get_cluster_pmu(l2cache_pmu, cpu);
    811	if (!cluster)
    812		return 0;
    813
    814	/* If this CPU is not managing the cluster, we're done */
    815	if (cluster->on_cpu != cpu)
    816		return 0;
    817
    818	/* Give up ownership of cluster */
    819	cpumask_clear_cpu(cpu, &l2cache_pmu->cpumask);
    820	cluster->on_cpu = -1;
    821
    822	/* Any other CPU for this cluster which is still online */
    823	cpumask_and(&cluster_online_cpus, &cluster->cluster_cpus,
    824		    cpu_online_mask);
    825	target = cpumask_any_but(&cluster_online_cpus, cpu);
    826	if (target >= nr_cpu_ids) {
    827		disable_irq(cluster->irq);
    828		return 0;
    829	}
    830
    831	perf_pmu_migrate_context(&l2cache_pmu->pmu, cpu, target);
    832	cluster->on_cpu = target;
    833	cpumask_set_cpu(target, &l2cache_pmu->cpumask);
    834	WARN_ON(irq_set_affinity(cluster->irq, cpumask_of(target)));
    835
    836	return 0;
    837}
    838
    839static int l2_cache_pmu_probe_cluster(struct device *dev, void *data)
    840{
    841	struct platform_device *pdev = to_platform_device(dev->parent);
    842	struct platform_device *sdev = to_platform_device(dev);
    843	struct acpi_device *adev = ACPI_COMPANION(dev);
    844	struct l2cache_pmu *l2cache_pmu = data;
    845	struct cluster_pmu *cluster;
    846	unsigned long fw_cluster_id;
    847	int err;
    848	int irq;
    849
    850	if (!adev || kstrtoul(adev->pnp.unique_id, 10, &fw_cluster_id) < 0) {
    851		dev_err(&pdev->dev, "unable to read ACPI uid\n");
    852		return -ENODEV;
    853	}
    854
    855	cluster = devm_kzalloc(&pdev->dev, sizeof(*cluster), GFP_KERNEL);
    856	if (!cluster)
    857		return -ENOMEM;
    858
    859	INIT_LIST_HEAD(&cluster->next);
    860	list_add(&cluster->next, &l2cache_pmu->clusters);
    861	cluster->cluster_id = fw_cluster_id;
    862
    863	irq = platform_get_irq(sdev, 0);
    864	if (irq < 0)
    865		return irq;
    866	cluster->irq = irq;
    867
    868	cluster->l2cache_pmu = l2cache_pmu;
    869	cluster->on_cpu = -1;
    870
    871	err = devm_request_irq(&pdev->dev, irq, l2_cache_handle_irq,
    872			       IRQF_NOBALANCING | IRQF_NO_THREAD |
    873			       IRQF_NO_AUTOEN,
    874			       "l2-cache-pmu", cluster);
    875	if (err) {
    876		dev_err(&pdev->dev,
    877			"Unable to request IRQ%d for L2 PMU counters\n", irq);
    878		return err;
    879	}
    880
    881	dev_info(&pdev->dev,
    882		"Registered L2 cache PMU cluster %ld\n", fw_cluster_id);
    883
    884	spin_lock_init(&cluster->pmu_lock);
    885
    886	l2cache_pmu->num_pmus++;
    887
    888	return 0;
    889}
    890
    891static int l2_cache_pmu_probe(struct platform_device *pdev)
    892{
    893	int err;
    894	struct l2cache_pmu *l2cache_pmu;
    895
    896	l2cache_pmu =
    897		devm_kzalloc(&pdev->dev, sizeof(*l2cache_pmu), GFP_KERNEL);
    898	if (!l2cache_pmu)
    899		return -ENOMEM;
    900
    901	INIT_LIST_HEAD(&l2cache_pmu->clusters);
    902
    903	platform_set_drvdata(pdev, l2cache_pmu);
    904	l2cache_pmu->pmu = (struct pmu) {
    905		/* suffix is instance id for future use with multiple sockets */
    906		.name		= "l2cache_0",
    907		.task_ctx_nr    = perf_invalid_context,
    908		.pmu_enable	= l2_cache_pmu_enable,
    909		.pmu_disable	= l2_cache_pmu_disable,
    910		.event_init	= l2_cache_event_init,
    911		.add		= l2_cache_event_add,
    912		.del		= l2_cache_event_del,
    913		.start		= l2_cache_event_start,
    914		.stop		= l2_cache_event_stop,
    915		.read		= l2_cache_event_read,
    916		.attr_groups	= l2_cache_pmu_attr_grps,
    917		.capabilities	= PERF_PMU_CAP_NO_EXCLUDE,
    918	};
    919
    920	l2cache_pmu->num_counters = get_num_counters();
    921	l2cache_pmu->pdev = pdev;
    922	l2cache_pmu->pmu_cluster = devm_alloc_percpu(&pdev->dev,
    923						     struct cluster_pmu *);
    924	if (!l2cache_pmu->pmu_cluster)
    925		return -ENOMEM;
    926
    927	l2_cycle_ctr_idx = l2cache_pmu->num_counters - 1;
    928	l2_counter_present_mask = GENMASK(l2cache_pmu->num_counters - 2, 0) |
    929		BIT(L2CYCLE_CTR_BIT);
    930
    931	cpumask_clear(&l2cache_pmu->cpumask);
    932
    933	/* Read cluster info and initialize each cluster */
    934	err = device_for_each_child(&pdev->dev, l2cache_pmu,
    935				    l2_cache_pmu_probe_cluster);
    936	if (err)
    937		return err;
    938
    939	if (l2cache_pmu->num_pmus == 0) {
    940		dev_err(&pdev->dev, "No hardware L2 cache PMUs found\n");
    941		return -ENODEV;
    942	}
    943
    944	err = cpuhp_state_add_instance(CPUHP_AP_PERF_ARM_QCOM_L2_ONLINE,
    945				       &l2cache_pmu->node);
    946	if (err) {
    947		dev_err(&pdev->dev, "Error %d registering hotplug", err);
    948		return err;
    949	}
    950
    951	err = perf_pmu_register(&l2cache_pmu->pmu, l2cache_pmu->pmu.name, -1);
    952	if (err) {
    953		dev_err(&pdev->dev, "Error %d registering L2 cache PMU\n", err);
    954		goto out_unregister;
    955	}
    956
    957	dev_info(&pdev->dev, "Registered L2 cache PMU using %d HW PMUs\n",
    958		 l2cache_pmu->num_pmus);
    959
    960	return err;
    961
    962out_unregister:
    963	cpuhp_state_remove_instance(CPUHP_AP_PERF_ARM_QCOM_L2_ONLINE,
    964				    &l2cache_pmu->node);
    965	return err;
    966}
    967
    968static int l2_cache_pmu_remove(struct platform_device *pdev)
    969{
    970	struct l2cache_pmu *l2cache_pmu =
    971		to_l2cache_pmu(platform_get_drvdata(pdev));
    972
    973	perf_pmu_unregister(&l2cache_pmu->pmu);
    974	cpuhp_state_remove_instance(CPUHP_AP_PERF_ARM_QCOM_L2_ONLINE,
    975				    &l2cache_pmu->node);
    976	return 0;
    977}
    978
    979static struct platform_driver l2_cache_pmu_driver = {
    980	.driver = {
    981		.name = "qcom-l2cache-pmu",
    982		.acpi_match_table = ACPI_PTR(l2_cache_pmu_acpi_match),
    983		.suppress_bind_attrs = true,
    984	},
    985	.probe = l2_cache_pmu_probe,
    986	.remove = l2_cache_pmu_remove,
    987};
    988
    989static int __init register_l2_cache_pmu_driver(void)
    990{
    991	int err;
    992
    993	err = cpuhp_setup_state_multi(CPUHP_AP_PERF_ARM_QCOM_L2_ONLINE,
    994				      "AP_PERF_ARM_QCOM_L2_ONLINE",
    995				      l2cache_pmu_online_cpu,
    996				      l2cache_pmu_offline_cpu);
    997	if (err)
    998		return err;
    999
   1000	return platform_driver_register(&l2_cache_pmu_driver);
   1001}
   1002device_initcall(register_l2_cache_pmu_driver);