drivers/devfreq/exynos/exynos_ppmu.c

   1 /*
   2  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
   3  *              http://www.samsung.com/
   4  *
   5  * EXYNOS - PPMU support
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/types.h>
  14 #include <linux/io.h>
  15
  16 #include "exynos_ppmu.h"
  17
  18 void exynos_ppmu_reset(void __iomem *ppmu_base)
  19 {
  20         __raw_writel(PPMU_CYCLE_RESET | PPMU_COUNTER_RESET, ppmu_base);
  21         __raw_writel(PPMU_ENABLE_CYCLE  |
  22                      PPMU_ENABLE_COUNT0 |
  23                      PPMU_ENABLE_COUNT1 |
  24                      PPMU_ENABLE_COUNT2 |
  25                      PPMU_ENABLE_COUNT3,
  26                      ppmu_base + PPMU_CNTENS);
  27 }
  28
  29 void exynos_ppmu_setevent(void __iomem *ppmu_base, unsigned int ch,
  30                         unsigned int evt)
  31 {
  32         __raw_writel(evt, ppmu_base + PPMU_BEVTSEL(ch));
  33 }
  34
  35 void exynos_ppmu_start(void __iomem *ppmu_base)
  36 {
  37         __raw_writel(PPMU_ENABLE, ppmu_base);
  38 }
  39
  40 void exynos_ppmu_stop(void __iomem *ppmu_base)
  41 {
  42         __raw_writel(PPMU_DISABLE, ppmu_base);
  43 }
  44
  45 unsigned int exynos_ppmu_read(void __iomem *ppmu_base, unsigned int ch)
  46 {
  47         unsigned int total;
  48
  49         if (ch == PPMU_PMNCNT3)
  50                 total = ((__raw_readl(ppmu_base + PMCNT_OFFSET(ch)) << 8) |
  51                           __raw_readl(ppmu_base + PMCNT_OFFSET(ch + 1)));
  52         else
  53                 total = __raw_readl(ppmu_base + PMCNT_OFFSET(ch));
  54
  55         return total;
  56 }
  57
  58 void busfreq_mon_reset(struct busfreq_ppmu_data *ppmu_data)
  59 {
  60         unsigned int i;
  61
  62         for (i = 0; i < ppmu_data->ppmu_end; i++) {
  63                 void __iomem *ppmu_base = ppmu_data->ppmu[i].hw_base;
  64
  65                 /* Reset the performance and cycle counters */
  66                 exynos_ppmu_reset(ppmu_base);
  67
  68                 /* Setup count registers to monitor read/write transactions */
  69                 ppmu_data->ppmu[i].event[PPMU_PMNCNT3] = RDWR_DATA_COUNT;
  70                 exynos_ppmu_setevent(ppmu_base, PPMU_PMNCNT3,
  71                                         ppmu_data->ppmu[i].event[PPMU_PMNCNT3]);
  72
  73                 exynos_ppmu_start(ppmu_base);
  74         }
  75 }
  76
  77 void exynos_read_ppmu(struct busfreq_ppmu_data *ppmu_data)
  78 {
  79         int i, j;
  80
  81         for (i = 0; i < ppmu_data->ppmu_end; i++) {
  82                 void __iomem *ppmu_base = ppmu_data->ppmu[i].hw_base;
  83
  84                 exynos_ppmu_stop(ppmu_base);
  85
  86                 /* Update local data from PPMU */
  87                 ppmu_data->ppmu[i].ccnt = __raw_readl(ppmu_base + PPMU_CCNT);
  88
  89                 for (j = PPMU_PMNCNT0; j < PPMU_PMNCNT_MAX; j++) {
  90                         if (ppmu_data->ppmu[i].event[j] == 0)
  91                                 ppmu_data->ppmu[i].count[j] = 0;
  92                         else
  93                                 ppmu_data->ppmu[i].count[j] =
  94                                         exynos_ppmu_read(ppmu_base, j);
  95                 }
  96         }
  97
  98         busfreq_mon_reset(ppmu_data);
  99 }
 100
 101 int exynos_get_busier_ppmu(struct busfreq_ppmu_data *ppmu_data)
 102 {
 103         unsigned int count = 0;
 104         int i, j, busy = 0;
 105
 106         for (i = 0; i < ppmu_data->ppmu_end; i++) {
 107                 for (j = PPMU_PMNCNT0; j < PPMU_PMNCNT_MAX; j++) {
 108                         if (ppmu_data->ppmu[i].count[j] > count) {
 109                                 count = ppmu_data->ppmu[i].count[j];
 110                                 busy = i;
 111                         }
 112                 }
 113         }
 114
 115         return busy;
 116 }