release/src-rt-6.x.4708/linux/linux-2.6.36/arch/mips/bcm63xx/clk.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
   7  */
   8
   9 #include <linux/module.h>
  10 #include <linux/mutex.h>
  11 #include <linux/err.h>
  12 #include <linux/clk.h>
  13 #include <bcm63xx_cpu.h>
  14 #include <bcm63xx_io.h>
  15 #include <bcm63xx_regs.h>
  16 #include <bcm63xx_clk.h>
  17
  18 static DEFINE_MUTEX(clocks_mutex);
  19
  20
  21 static void clk_enable_unlocked(struct clk *clk)
  22 {
  23         if (clk->set && (clk->usage++) == 0)
  24                 clk->set(clk, 1);
  25 }
  26
  27 static void clk_disable_unlocked(struct clk *clk)
  28 {
  29         if (clk->set && (--clk->usage) == 0)
  30                 clk->set(clk, 0);
  31 }
  32
  33 static void bcm_hwclock_set(u32 mask, int enable)
  34 {
  35         u32 reg;
  36
  37         reg = bcm_perf_readl(PERF_CKCTL_REG);
  38         if (enable)
  39                 reg |= mask;
  40         else
  41                 reg &= ~mask;
  42         bcm_perf_writel(reg, PERF_CKCTL_REG);
  43 }
  44
  45 /*
  46  * Ethernet MAC "misc" clock: dma clocks and main clock on 6348
  47  */
  48 static void enet_misc_set(struct clk *clk, int enable)
  49 {
  50         u32 mask;
  51
  52         if (BCMCPU_IS_6338())
  53                 mask = CKCTL_6338_ENET_EN;
  54         else if (BCMCPU_IS_6345())
  55                 mask = CKCTL_6345_ENET_EN;
  56         else if (BCMCPU_IS_6348())
  57                 mask = CKCTL_6348_ENET_EN;
  58         else
  59                 /* BCMCPU_IS_6358 */
  60                 mask = CKCTL_6358_EMUSB_EN;
  61         bcm_hwclock_set(mask, enable);
  62 }
  63
  64 static struct clk clk_enet_misc = {
  65         .set    = enet_misc_set,
  66 };
  67
  68 /*
  69  * Ethernet MAC clocks: only revelant on 6358, silently enable misc
  70  * clocks
  71  */
  72 static void enetx_set(struct clk *clk, int enable)
  73 {
  74         if (enable)
  75                 clk_enable_unlocked(&clk_enet_misc);
  76         else
  77                 clk_disable_unlocked(&clk_enet_misc);
  78
  79         if (BCMCPU_IS_6358()) {
  80                 u32 mask;
  81
  82                 if (clk->id == 0)
  83                         mask = CKCTL_6358_ENET0_EN;
  84                 else
  85                         mask = CKCTL_6358_ENET1_EN;
  86                 bcm_hwclock_set(mask, enable);
  87         }
  88 }
  89
  90 static struct clk clk_enet0 = {
  91         .id     = 0,
  92         .set    = enetx_set,
  93 };
  94
  95 static struct clk clk_enet1 = {
  96         .id     = 1,
  97         .set    = enetx_set,
  98 };
  99
 100 /*
 101  * Ethernet PHY clock
 102  */
 103 static void ephy_set(struct clk *clk, int enable)
 104 {
 105         if (!BCMCPU_IS_6358())
 106                 return;
 107         bcm_hwclock_set(CKCTL_6358_EPHY_EN, enable);
 108 }
 109
 110
 111 static struct clk clk_ephy = {
 112         .set    = ephy_set,
 113 };
 114
 115 /*
 116  * PCM clock
 117  */
 118 static void pcm_set(struct clk *clk, int enable)
 119 {
 120         if (!BCMCPU_IS_6358())
 121                 return;
 122         bcm_hwclock_set(CKCTL_6358_PCM_EN, enable);
 123 }
 124
 125 static struct clk clk_pcm = {
 126         .set    = pcm_set,
 127 };
 128
 129 /*
 130  * USB host clock
 131  */
 132 static void usbh_set(struct clk *clk, int enable)
 133 {
 134         if (!BCMCPU_IS_6348())
 135                 return;
 136         bcm_hwclock_set(CKCTL_6348_USBH_EN, enable);
 137 }
 138
 139 static struct clk clk_usbh = {
 140         .set    = usbh_set,
 141 };
 142
 143 /*
 144  * SPI clock
 145  */
 146 static void spi_set(struct clk *clk, int enable)
 147 {
 148         u32 mask;
 149
 150         if (BCMCPU_IS_6338())
 151                 mask = CKCTL_6338_SPI_EN;
 152         else if (BCMCPU_IS_6348())
 153                 mask = CKCTL_6348_SPI_EN;
 154         else
 155                 /* BCMCPU_IS_6358 */
 156                 mask = CKCTL_6358_SPI_EN;
 157         bcm_hwclock_set(mask, enable);
 158 }
 159
 160 static struct clk clk_spi = {
 161         .set    = spi_set,
 162 };
 163
 164 /*
 165  * Internal peripheral clock
 166  */
 167 static struct clk clk_periph = {
 168         .rate   = (50 * 1000 * 1000),
 169 };
 170
 171
 172 /*
 173  * Linux clock API implementation
 174  */
 175 int clk_enable(struct clk *clk)
 176 {
 177         mutex_lock(&clocks_mutex);
 178         clk_enable_unlocked(clk);
 179         mutex_unlock(&clocks_mutex);
 180         return 0;
 181 }
 182
 183 EXPORT_SYMBOL(clk_enable);
 184
 185 void clk_disable(struct clk *clk)
 186 {
 187         mutex_lock(&clocks_mutex);
 188         clk_disable_unlocked(clk);
 189         mutex_unlock(&clocks_mutex);
 190 }
 191
 192 EXPORT_SYMBOL(clk_disable);
 193
 194 unsigned long clk_get_rate(struct clk *clk)
 195 {
 196         return clk->rate;
 197 }
 198
 199 EXPORT_SYMBOL(clk_get_rate);
 200
 201 struct clk *clk_get(struct device *dev, const char *id)
 202 {
 203         if (!strcmp(id, "enet0"))
 204                 return &clk_enet0;
 205         if (!strcmp(id, "enet1"))
 206                 return &clk_enet1;
 207         if (!strcmp(id, "ephy"))
 208                 return &clk_ephy;
 209         if (!strcmp(id, "usbh"))
 210                 return &clk_usbh;
 211         if (!strcmp(id, "spi"))
 212                 return &clk_spi;
 213         if (!strcmp(id, "periph"))
 214                 return &clk_periph;
 215         if (BCMCPU_IS_6358() && !strcmp(id, "pcm"))
 216                 return &clk_pcm;
 217         return ERR_PTR(-ENOENT);
 218 }
 219
 220 EXPORT_SYMBOL(clk_get);
 221
 222 void clk_put(struct clk *clk)
 223 {
 224 }
 225
 226 EXPORT_SYMBOL(clk_put);