driver/gator_events_l2c-310.c

   1 /**
   2  * l2c310 (L2 Cache Controller) event counters for gator
   3  *
   4  * Copyright (C) ARM Limited 2010-2012. All rights reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11 #include <linux/init.h>
  12 #include <linux/io.h>
  13 #include <asm/hardware/cache-l2x0.h>
  14
  15 #include "gator.h"
  16
  17 #define L2C310_COUNTERS_NUM 2
  18
  19 static struct {
  20         unsigned long enabled;
  21         unsigned long event;
  22         unsigned long key;
  23 } l2c310_counters[L2C310_COUNTERS_NUM];
  24
  25 static int l2c310_buffer[L2C310_COUNTERS_NUM * 2];
  26
  27 static void __iomem *l2c310_base;
  28
  29
  30
  31 static void gator_events_l2c310_reset_counters(void)
  32 {
  33         u32 val = readl(l2c310_base + L2X0_EVENT_CNT_CTRL);
  34
  35         val |= ((1 << L2C310_COUNTERS_NUM) - 1) << 1;
  36
  37         writel(val, l2c310_base + L2X0_EVENT_CNT_CTRL);
  38 }
  39
  40
  41 static int gator_events_l2c310_create_files(struct super_block *sb,
  42                 struct dentry *root)
  43 {
  44         int i;
  45
  46         for (i = 0; i < L2C310_COUNTERS_NUM; i++) {
  47                 char buf[16];
  48                 struct dentry *dir;
  49
  50                 snprintf(buf, sizeof(buf), "L2C-310_cnt%d", i);
  51                 dir = gatorfs_mkdir(sb, root, buf);
  52                 if (WARN_ON(!dir))
  53                         return -1;
  54                 gatorfs_create_ulong(sb, dir, "enabled",
  55                                 &l2c310_counters[i].enabled);
  56                 gatorfs_create_ulong(sb, dir, "event",
  57                                 &l2c310_counters[i].event);
  58                 gatorfs_create_ro_ulong(sb, dir, "key",
  59                                 &l2c310_counters[i].key);
  60         }
  61
  62         return 0;
  63 }
  64
  65 static int gator_events_l2c310_start(void)
  66 {
  67         static const unsigned long l2x0_event_cntx_cfg[L2C310_COUNTERS_NUM] = {
  68                 L2X0_EVENT_CNT0_CFG,
  69                 L2X0_EVENT_CNT1_CFG,
  70         };
  71         int i;
  72
  73         /* Counter event sources */
  74         for (i = 0; i < L2C310_COUNTERS_NUM; i++)
  75                 writel((l2c310_counters[i].event & 0xf) << 2,
  76                                 l2c310_base + l2x0_event_cntx_cfg[i]);
  77
  78         gator_events_l2c310_reset_counters();
  79
  80         /* Event counter enable */
  81         writel(1, l2c310_base + L2X0_EVENT_CNT_CTRL);
  82
  83         return 0;
  84 }
  85
  86 static void gator_events_l2c310_stop(void)
  87 {
  88         /* Event counter disable */
  89         writel(0, l2c310_base + L2X0_EVENT_CNT_CTRL);
  90 }
  91
  92 static int gator_events_l2c310_read(int **buffer)
  93 {
  94         static const unsigned long l2x0_event_cntx_val[L2C310_COUNTERS_NUM] = {
  95                 L2X0_EVENT_CNT0_VAL,
  96                 L2X0_EVENT_CNT1_VAL,
  97         };
  98         int i;
  99         int len = 0;
 100
 101         if (smp_processor_id())
 102                 return 0;
 103
 104         for (i = 0; i < L2C310_COUNTERS_NUM; i++) {
 105                 if (l2c310_counters[i].enabled) {
 106                         l2c310_buffer[len++] = l2c310_counters[i].key;
 107                         l2c310_buffer[len++] = readl(l2c310_base +
 108                                         l2x0_event_cntx_val[i]);
 109                 }
 110         }
 111
 112         /* l2c310 counters are saturating, not wrapping in case of overflow */
 113         gator_events_l2c310_reset_counters();
 114
 115         if (buffer)
 116                 *buffer = l2c310_buffer;
 117
 118         return len;
 119 }
 120
 121 static struct gator_interface gator_events_l2c310_interface = {
 122         .create_files = gator_events_l2c310_create_files,
 123         .start = gator_events_l2c310_start,
 124         .stop = gator_events_l2c310_stop,
 125         .read = gator_events_l2c310_read,
 126 };
 127
 128 static void __maybe_unused gator_events_l2c310_probe(unsigned long phys)
 129 {
 130         if (l2c310_base)
 131                 return;
 132
 133         l2c310_base = ioremap(phys, SZ_4K);
 134         if (l2c310_base) {
 135                 u32 cache_id = readl(l2c310_base + L2X0_CACHE_ID);
 136
 137                 if ((cache_id & 0xff0003c0) != 0x410000c0) {
 138                         iounmap(l2c310_base);
 139                         l2c310_base = NULL;
 140                 }
 141         }
 142 }
 143
 144 int gator_events_l2c310_init(void)
 145 {
 146         int i;
 147
 148         if (gator_cpuid() != CORTEX_A5 && gator_cpuid() != CORTEX_A9)
 149                 return -1;
 150
 151 #if defined(CONFIG_ARCH_EXYNOS4) || defined(CONFIG_ARCH_S5PV310)
 152         gator_events_l2c310_probe(0x10502000);
 153 #endif
 154 #if defined(CONFIG_ARCH_OMAP4)
 155         gator_events_l2c310_probe(0x48242000);
 156 #endif
 157 #if defined(CONFIG_ARCH_TEGRA)
 158         gator_events_l2c310_probe(0x50043000);
 159 #endif
 160 #if defined(CONFIG_ARCH_U8500)
 161         gator_events_l2c310_probe(0xa0412000);
 162 #endif
 163 #if defined(CONFIG_ARCH_VEXPRESS)
 164         // A9x4 core tile (HBI-0191)
 165         gator_events_l2c310_probe(0x1e00a000);
 166         // New memory map tiles
 167         gator_events_l2c310_probe(0x2c0f0000);
 168 #endif
 169         if (!l2c310_base)
 170                 return -1;
 171
 172         for (i = 0; i < L2C310_COUNTERS_NUM; i++) {
 173                 l2c310_counters[i].enabled = 0;
 174                 l2c310_counters[i].key = gator_events_get_key();
 175         }
 176
 177         return gator_events_install(&gator_events_l2c310_interface);
 178 }
 179 gator_events_init(gator_events_l2c310_init);