diff options
Diffstat (limited to 'arch/arm/mach-s3c2440/clock.c')
| -rw-r--r-- | arch/arm/mach-s3c2440/clock.c | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/arch/arm/mach-s3c2440/clock.c b/arch/arm/mach-s3c2440/clock.c new file mode 100644 index 000000000000..79e2ea4adaf3 --- /dev/null +++ b/arch/arm/mach-s3c2440/clock.c | |||
| @@ -0,0 +1,170 @@ | |||
| 1 | /* linux/arch/arm/mach-s3c2440/clock.c | ||
| 2 | * | ||
| 3 | * Copyright (c) 2004-2005 Simtec Electronics | ||
| 4 | * http://armlinux.simtec.co.uk/ | ||
| 5 | * Ben Dooks <ben@simtec.co.uk> | ||
| 6 | * | ||
| 7 | * S3C2440 Clock support | ||
| 8 | * | ||
| 9 | * This program is free software; you can redistribute it and/or modify | ||
| 10 | * it under the terms of the GNU General Public License as published by | ||
| 11 | * the Free Software Foundation; either version 2 of the License, or | ||
| 12 | * (at your option) any later version. | ||
| 13 | * | ||
| 14 | * This program is distributed in the hope that it will be useful, | ||
| 15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
| 16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
| 17 | * GNU General Public License for more details. | ||
| 18 | * | ||
| 19 | * You should have received a copy of the GNU General Public License | ||
| 20 | * along with this program; if not, write to the Free Software | ||
| 21 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | ||
| 22 | */ | ||
| 23 | |||
| 24 | #include <linux/init.h> | ||
| 25 | #include <linux/module.h> | ||
| 26 | #include <linux/kernel.h> | ||
| 27 | #include <linux/list.h> | ||
| 28 | #include <linux/errno.h> | ||
| 29 | #include <linux/err.h> | ||
| 30 | #include <linux/device.h> | ||
| 31 | #include <linux/sysdev.h> | ||
| 32 | #include <linux/interrupt.h> | ||
| 33 | #include <linux/ioport.h> | ||
| 34 | #include <linux/mutex.h> | ||
| 35 | #include <linux/clk.h> | ||
| 36 | |||
| 37 | #include <asm/hardware.h> | ||
| 38 | #include <asm/atomic.h> | ||
| 39 | #include <asm/irq.h> | ||
| 40 | #include <asm/io.h> | ||
| 41 | |||
| 42 | #include <asm/arch/regs-clock.h> | ||
| 43 | |||
| 44 | #include <asm/plat-s3c24xx/clock.h> | ||
| 45 | #include <asm/plat-s3c24xx/cpu.h> | ||
| 46 | |||
| 47 | /* S3C2440 extended clock support */ | ||
| 48 | |||
| 49 | static unsigned long s3c2440_camif_upll_round(struct clk *clk, | ||
| 50 | unsigned long rate) | ||
| 51 | { | ||
| 52 | unsigned long parent_rate = clk_get_rate(clk->parent); | ||
| 53 | int div; | ||
| 54 | |||
| 55 | if (rate > parent_rate) | ||
| 56 | return parent_rate; | ||
| 57 | |||
| 58 | /* note, we remove the +/- 1 calculations for the divisor */ | ||
| 59 | |||
| 60 | div = (parent_rate / rate) / 2; | ||
| 61 | |||
| 62 | if (div < 1) | ||
| 63 | div = 1; | ||
| 64 | else if (div > 16) | ||
| 65 | div = 16; | ||
| 66 | |||
| 67 | return parent_rate / (div * 2); | ||
| 68 | } | ||
| 69 | |||
| 70 | static int s3c2440_camif_upll_setrate(struct clk *clk, unsigned long rate) | ||
| 71 | { | ||
| 72 | unsigned long parent_rate = clk_get_rate(clk->parent); | ||
| 73 | unsigned long camdivn = __raw_readl(S3C2440_CAMDIVN); | ||
| 74 | |||
| 75 | rate = s3c2440_camif_upll_round(clk, rate); | ||
| 76 | |||
| 77 | camdivn &= ~(S3C2440_CAMDIVN_CAMCLK_SEL | S3C2440_CAMDIVN_CAMCLK_MASK); | ||
| 78 | |||
| 79 | if (rate != parent_rate) { | ||
| 80 | camdivn |= S3C2440_CAMDIVN_CAMCLK_SEL; | ||
| 81 | camdivn |= (((parent_rate / rate) / 2) - 1); | ||
| 82 | } | ||
| 83 | |||
| 84 | __raw_writel(camdivn, S3C2440_CAMDIVN); | ||
| 85 | |||
| 86 | return 0; | ||
| 87 | } | ||
| 88 | |||
| 89 | /* Extra S3C2440 clocks */ | ||
| 90 | |||
| 91 | static struct clk s3c2440_clk_cam = { | ||
| 92 | .name = "camif", | ||
| 93 | .id = -1, | ||
| 94 | .enable = s3c2410_clkcon_enable, | ||
| 95 | .ctrlbit = S3C2440_CLKCON_CAMERA, | ||
| 96 | }; | ||
| 97 | |||
| 98 | static struct clk s3c2440_clk_cam_upll = { | ||
| 99 | .name = "camif-upll", | ||
| 100 | .id = -1, | ||
| 101 | .set_rate = s3c2440_camif_upll_setrate, | ||
| 102 | .round_rate = s3c2440_camif_upll_round, | ||
| 103 | }; | ||
| 104 | |||
| 105 | static struct clk s3c2440_clk_ac97 = { | ||
| 106 | .name = "ac97", | ||
| 107 | .id = -1, | ||
| 108 | .enable = s3c2410_clkcon_enable, | ||
| 109 | .ctrlbit = S3C2440_CLKCON_CAMERA, | ||
| 110 | }; | ||
| 111 | |||
| 112 | static int s3c2440_clk_add(struct sys_device *sysdev) | ||
| 113 | { | ||
| 114 | unsigned long camdivn = __raw_readl(S3C2440_CAMDIVN); | ||
| 115 | unsigned long clkdivn; | ||
| 116 | struct clk *clock_h; | ||
| 117 | struct clk *clock_p; | ||
| 118 | struct clk *clock_upll; | ||
| 119 | |||
| 120 | printk("S3C2440: Clock Support, DVS %s\n", | ||
| 121 | (camdivn & S3C2440_CAMDIVN_DVSEN) ? "on" : "off"); | ||
| 122 | |||
| 123 | clock_p = clk_get(NULL, "pclk"); | ||
| 124 | clock_h = clk_get(NULL, "hclk"); | ||
| 125 | clock_upll = clk_get(NULL, "upll"); | ||
| 126 | |||
| 127 | if (IS_ERR(clock_p) || IS_ERR(clock_h) || IS_ERR(clock_upll)) { | ||
| 128 | printk(KERN_ERR "S3C2440: Failed to get parent clocks\n"); | ||
| 129 | return -EINVAL; | ||
| 130 | } | ||
| 131 | |||
| 132 | /* check rate of UPLL, and if it is near 96MHz, then change | ||
| 133 | * to using half the UPLL rate for the system */ | ||
| 134 | |||
| 135 | if (clk_get_rate(clock_upll) > (94 * MHZ)) { | ||
| 136 | clk_usb_bus.rate = clk_get_rate(clock_upll) / 2; | ||
| 137 | |||
| 138 | mutex_lock(&clocks_mutex); | ||
| 139 | |||
| 140 | clkdivn = __raw_readl(S3C2410_CLKDIVN); | ||
| 141 | clkdivn |= S3C2440_CLKDIVN_UCLK; | ||
| 142 | __raw_writel(clkdivn, S3C2410_CLKDIVN); | ||
| 143 | |||
| 144 | mutex_unlock(&clocks_mutex); | ||
| 145 | } | ||
| 146 | |||
| 147 | s3c2440_clk_cam.parent = clock_h; | ||
| 148 | s3c2440_clk_ac97.parent = clock_p; | ||
| 149 | s3c2440_clk_cam_upll.parent = clock_upll; | ||
| 150 | |||
| 151 | s3c24xx_register_clock(&s3c2440_clk_ac97); | ||
| 152 | s3c24xx_register_clock(&s3c2440_clk_cam); | ||
| 153 | s3c24xx_register_clock(&s3c2440_clk_cam_upll); | ||
| 154 | |||
| 155 | clk_disable(&s3c2440_clk_ac97); | ||
| 156 | clk_disable(&s3c2440_clk_cam); | ||
| 157 | |||
| 158 | return 0; | ||
| 159 | } | ||
| 160 | |||
| 161 | static struct sysdev_driver s3c2440_clk_driver = { | ||
| 162 | .add = s3c2440_clk_add, | ||
| 163 | }; | ||
| 164 | |||
| 165 | static __init int s3c24xx_clk_driver(void) | ||
| 166 | { | ||
| 167 | return sysdev_driver_register(&s3c2440_sysclass, &s3c2440_clk_driver); | ||
| 168 | } | ||
| 169 | |||
| 170 | arch_initcall(s3c24xx_clk_driver); | ||
