/* linux/arch/arm/mach-s3c2412/clock.c * * Copyright (c) 2006 Simtec Electronics * Ben Dooks <ben@simtec.co.uk> * * S3C2412,S3C2413 Clock control support * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include <linux/init.h> #include <linux/module.h> #include <linux/kernel.h> #include <linux/list.h> #include <linux/errno.h> #include <linux/err.h> #include <linux/device.h> #include <linux/clk.h> #include <linux/mutex.h> #include <linux/delay.h> #include <linux/serial_core.h> #include <linux/io.h> #include <asm/mach/map.h> #include <mach/hardware.h> #include <plat/regs-serial.h> #include <mach/regs-clock.h> #include <mach/regs-gpio.h> #include <plat/s3c2412.h> #include <plat/clock.h> #include <plat/cpu.h> /* We currently have to assume that the system is running * from the XTPll input, and that all ***REFCLKs are being * fed from it, as we cannot read the state of OM[4] from * software. * * It would be possible for each board initialisation to * set the correct muxing at initialisation */ static int s3c2412_clkcon_enable(struct clk *clk, int enable) { unsigned int clocks = clk->ctrlbit; unsigned long clkcon; clkcon = __raw_readl(S3C2410_CLKCON); if (enable) clkcon |= clocks; else clkcon &= ~clocks; __raw_writel(clkcon, S3C2410_CLKCON); return 0; } static int s3c2412_upll_enable(struct clk *clk, int enable) { unsigned long upllcon = __raw_readl(S3C2410_UPLLCON); unsigned long orig = upllcon; if (!enable) upllcon |= S3C2412_PLLCON_OFF; else upllcon &= ~S3C2412_PLLCON_OFF; __raw_writel(upllcon, S3C2410_UPLLCON); /* allow ~150uS for the PLL to settle and lock */ if (enable && (orig & S3C2412_PLLCON_OFF)) udelay(150); return 0; } /* clock selections */ static struct clk clk_erefclk = { .name = "erefclk", }; static struct clk clk_urefclk = { .name = "urefclk", }; static int s3c2412_setparent_usysclk(struct clk *clk, struct clk *parent) { unsigned long clksrc = __raw_readl(S3C2412_CLKSRC); if (parent == &clk_urefclk) clksrc &= ~S3C2412_CLKSRC_USYSCLK_UPLL; else if (parent == &clk_upll) clksrc |= S3C2412_CLKSRC_USYSCLK_UPLL; else return -EINVAL; clk->parent = parent; __raw_writel(clksrc, S3C2412_CLKSRC); return 0; } static struct clk clk_usysclk = { .name = "usysclk", .parent = &clk_xtal, .ops = &(struct clk_ops) { .set_parent = s3c2412_setparent_usysclk, }, }; static struct clk clk_mrefclk = { .name = "mrefclk", .parent = &clk_xtal, }; static struct clk clk_mdivclk = { .name = "mdivclk", .parent = &clk_xtal, }; static int s3c2412_setparent_usbsrc(struct clk *clk, struct clk *parent) { unsigned long clksrc = __raw_readl(S3C2412_CLKSRC); if (parent == &clk_usysclk) clksrc &= ~S3C2412_CLKSRC_USBCLK_HCLK; else if (parent == &clk_h) clksrc |= S3C2412_CLKSRC_USBCLK_HCLK; else return -EINVAL; clk->parent = parent; __raw_writel(clksrc, S3C2412_CLKSRC); return 0; } static unsigned long s3c2412_roundrate_usbsrc(struct clk *clk, unsigned long rate) { unsigned long parent_rate = clk_get_rate(clk->parent); int div; if (rate > parent_rate) return parent_rate; div = parent_rate / rate; if (div > 2) div = 2; return parent_rate / div; } static unsigned long s3c2412_getrate_usbsrc(struct clk *clk) { unsigned long parent_rate = clk_get_rate(clk->parent); unsigned long div = __raw_readl(S3C2410_CLKDIVN); return parent_rate / ((div & S3C2412_CLKDIVN_USB48DIV) ? 2 : 1); } static int s3c2412_setrate_usbsrc(struct clk *clk, unsigned long rate) { unsigned long parent_rate = clk_get_rate(clk->parent); unsigned long clkdivn = __raw_readl(S3C2410_CLKDIVN); rate = s3c2412_roundrate_usbsrc(clk, rate); if ((parent_rate / rate) == 2) clkdivn |= S3C2412_CLKDIVN_USB48DIV; else clkdivn &= ~S3C2412_CLKDIVN_USB48DIV; __raw_writel(clkdivn, S3C2410_CLKDIVN); return 0; } static struct clk clk_usbsrc = { .name = "usbsrc", .ops = &(struct clk_ops) { .get_rate = s3c2412_getrate_usbsrc, .set_rate = s3c2412_setrate_usbsrc, .round_rate = s3c2412_roundrate_usbsrc, .set_parent = s3c2412_setparent_usbsrc, }, }; static int s3c2412_setparent_msysclk(struct clk *clk, struct clk *parent) { unsigned long clksrc = __raw_readl(S3C2412_CLKSRC); if (parent == &clk_mdivclk) clksrc &= ~S3C2412_CLKSRC_MSYSCLK_MPLL; else if (parent == &clk_mpll) clksrc |= S3C2412_CLKSRC_MSYSCLK_MPLL; else return -EINVAL; clk->parent = parent; __raw_writel(clksrc, S3C2412_CLKSRC); return 0; } static struct clk clk_msysclk = { .name = "msysclk", .ops = &(struct clk_ops) { .set_parent = s3c2412_setparent_msysclk, }, }; static int s3c2412_setparent_armclk(struct clk *clk, struct clk *parent) { unsigned long flags; unsigned long clkdiv; unsigned long dvs; /* Note, we current equate fclk andf msysclk for S3C2412 */ if (parent == &clk_msysclk || parent == &clk_f) dvs = 0; else if (parent == &clk_h) dvs = S3C2412_CLKDIVN_DVSEN; else return -EINVAL; clk->parent = parent; /* update this under irq lockdown, clkdivn is not protected * by the clock system. */ local_irq_save(flags); clkdiv = __raw_readl(S3C2410_CLKDIVN); clkdiv &= ~S3C2412_CLKDIVN_DVSEN; clkdiv |= dvs; __raw_writel(clkdiv, S3C2410_CLKDIVN); local_irq_restore(flags); return 0; } static struct clk clk_armclk = { .name = "armclk", .parent = &clk_msysclk, .ops = &(struct clk_ops) { .set_parent = s3c2412_setparent_armclk, }, }; /* these next clocks have an divider immediately after them, * so we can register them with their divider and leave out the * intermediate clock stage */ static unsigned long s3c2412_roundrate_clksrc(struct clk *clk, unsigned long rate) { unsigned long parent_rate = clk_get_rate(clk->parent); int div; if (rate > parent_rate) return parent_rate; /* note, we remove the +/- 1 calculations as they cancel out */ div = (rate / parent_rate); if (div < 1) div = 1; else if (div > 16) div = 16; return parent_rate / div; } static int s3c2412_setparent_uart(struct clk *clk, struct clk *parent) { unsigned long clksrc = __raw_readl(S3C2412_CLKSRC); if (parent == &clk_erefclk) clksrc &= ~S3C2412_CLKSRC_UARTCLK_MPLL; else if (parent == &clk_mpll) clksrc |= S3C2412_CLKSRC_UARTCLK_MPLL; else return -EINVAL; clk->parent = parent; __raw_writel(clksrc, S3C2412_CLKSRC); return 0; } static unsigned long s3c2412_getrate_uart(struct clk *clk) { unsigned long parent_rate = clk_get_rate(clk->parent); unsigned long div = __raw_readl(S3C2410_CLKDIVN); div &= S3C2412_CLKDIVN_UARTDIV_MASK; div >>= S3C2412_CLKDIVN_UARTDIV_SHIFT; return parent_rate / (div + 1); } static int s3c2412_setrate_uart(struct clk *clk, unsigned long rate) { unsigned long parent_rate = clk_get_rate(clk->parent); unsigned long clkdivn = __raw_readl(S3C2410_CLKDIVN); rate = s3c2412_roundrate_clksrc(clk, rate); clkdivn &= ~S3C2412_CLKDIVN_UARTDIV_MASK; clkdivn |= ((parent_rate / rate) - 1) << S3C2412_CLKDIVN_UARTDIV_SHIFT; __raw_writel(clkdivn, S3C2410_CLKDIVN); return 0; } static struct clk clk_uart = { .name = "uartclk", .ops = &(struct clk_ops) { .get_rate = s3c2412_getrate_uart, .set_rate = s3c2412_setrate_uart, .set_parent = s3c2412_setparent_uart, .round_rate = s3c2412_roundrate_clksrc, }, }; static int s3c2412_setparent_i2s(struct clk *clk, struct clk *parent) { unsigned long clksrc = __raw_readl(S3C2412_CLKSRC); if (parent == &clk_erefclk) clksrc &= ~S3C2412_CLKSRC_I2SCLK_MPLL; else if (parent == &clk_mpll) clksrc |= S3C2412_CLKSRC_I2SCLK_MPLL; else return -EINVAL; clk->parent = parent; __raw_writel(clksrc, S3C2412_CLKSRC); return 0; } static unsigned long s3c2412_getrate_i2s(struct clk *clk) { unsigned long parent_rate = clk_get_rate(clk->parent); unsigned long div = __raw_readl(S3C2410_CLKDIVN); div &= S3C2412_CLKDIVN_I2SDIV_MASK; div >>= S3C2412_CLKDIVN_I2SDIV_SHIFT; return parent_rate / (div + 1); } static int s3c2412_setrate_i2s(struct clk *clk, unsigned long rate) { unsigned long parent_rate = clk_get_rate(clk->parent); unsigned long clkdivn = __raw_readl(S3C2410_CLKDIVN); rate = s3c2412_roundrate_clksrc(clk, rate); clkdivn &= ~S3C2412_CLKDIVN_I2SDIV_MASK; clkdivn |= ((parent_rate / rate) - 1) << S3C2412_CLKDIVN_I2SDIV_SHIFT; __raw_writel(clkdivn, S3C2410_CLKDIVN); return 0; } static struct clk clk_i2s = { .name = "i2sclk", .ops = &(struct clk_ops) { .get_rate = s3c2412_getrate_i2s, .set_rate = s3c2412_setrate_i2s, .set_parent = s3c2412_setparent_i2s, .round_rate = s3c2412_roundrate_clksrc, }, }; static int s3c2412_setparent_cam(struct clk *clk, struct clk *parent) { unsigned long clksrc = __raw_readl(S3C2412_CLKSRC); if (parent == &clk_usysclk) clksrc &= ~S3C2412_CLKSRC_CAMCLK_HCLK; else if (parent == &clk_h) clksrc |= S3C2412_CLKSRC_CAMCLK_HCLK; else return -EINVAL; clk->parent = parent; __raw_writel(clksrc, S3C2412_CLKSRC); return 0; } static unsigned long s3c2412_getrate_cam(struct clk *clk) { unsigned long parent_rate = clk_get_rate(clk->parent); unsigned long div = __raw_readl(S3C2410_CLKDIVN); div &= S3C2412_CLKDIVN_CAMDIV_MASK; div >>= S3C2412_CLKDIVN_CAMDIV_SHIFT; return parent_rate / (div + 1); } static int s3c2412_setrate_cam(struct clk *clk, unsigned long rate) { unsigned long parent_rate = clk_get_rate(clk->parent); unsigned long clkdivn = __raw_readl(S3C2410_CLKDIVN); rate = s3c2412_roundrate_clksrc(clk, rate); clkdivn &= ~S3C2412_CLKDIVN_CAMDIV_MASK; clkdivn |= ((parent_rate / rate) - 1) << S3C2412_CLKDIVN_CAMDIV_SHIFT; __raw_writel(clkdivn, S3C2410_CLKDIVN); return 0; } static struct clk clk_cam = { .name = "camif-upll", /* same as 2440 name */ .ops = &(struct clk_ops) { .get_rate = s3c2412_getrate_cam, .set_rate = s3c2412_setrate_cam, .set_parent = s3c2412_setparent_cam, .round_rate = s3c2412_roundrate_clksrc, }, }; /* standard clock definitions */ static struct clk init_clocks_disable[] = { { .name = "nand", .parent = &clk_h, .enable = s3c2412_clkcon_enable, .ctrlbit = S3C2412_CLKCON_NAND, }, { .name = "sdi", .parent = &clk_p, .enable = s3c2412_clkcon_enable, .ctrlbit = S3C2412_CLKCON_SDI, }, { .name = "adc", .parent = &clk_p, .enable = s3c2412_clkcon_enable, .ctrlbit = S3C2412_CLKCON_ADC, }, { .name = "i2c", .parent = &clk_p, .enable = s3c2412_clkcon_enable, .ctrlbit = S3C2412_CLKCON_IIC, }, { .name = "iis", .parent = &clk_p, .enable = s3c2412_clkcon_enable, .ctrlbit = S3C2412_CLKCON_IIS, }, { .name = "spi", .parent = &clk_p, .enable = s3c2412_clkcon_enable, .ctrlbit = S3C2412_CLKCON_SPI, } }; static struct clk init_clocks[] = { { .name = "dma", .parent = &clk_h, .enable = s3c2412_clkcon_enable, .ctrlbit = S3C2412_CLKCON_DMA0, }, { .name = "dma", .parent = &clk_h, .enable = s3c2412_clkcon_enable, .ctrlbit = S3C2412_CLKCON_DMA1, }, { .name = "dma", .parent = &clk_h, .enable = s3c2412_clkcon_enable, .ctrlbit = S3C2412_CLKCON_DMA2, }, { .name = "dma", .parent = &clk_h, .enable = s3c2412_clkcon_enable, .ctrlbit = S3C2412_CLKCON_DMA3, }, { .name = "lcd", .parent = &clk_h, .enable = s3c2412_clkcon_enable, .ctrlbit = S3C2412_CLKCON_LCDC, }, { .name = "gpio", .parent = &clk_p, .enable = s3c2412_clkcon_enable, .ctrlbit = S3C2412_CLKCON_GPIO, }, { .name = "usb-host", .parent = &clk_h, .enable = s3c2412_clkcon_enable, .ctrlbit = S3C2412_CLKCON_USBH, }, { .name = "usb-device", .parent = &clk_h, .enable = s3c2412_clkcon_enable, .ctrlbit = S3C2412_CLKCON_USBD, }, { .name = "timers", .parent = &clk_p, .enable = s3c2412_clkcon_enable, .ctrlbit = S3C2412_CLKCON_PWMT, }, { .name = "uart", .devname = "s3c2412-uart.0", .parent = &clk_p, .enable = s3c2412_clkcon_enable, .ctrlbit = S3C2412_CLKCON_UART0, }, { .name = "uart", .devname = "s3c2412-uart.1", .parent = &clk_p, .enable = s3c2412_clkcon_enable, .ctrlbit = S3C2412_CLKCON_UART1, }, { .name = "uart", .devname = "s3c2412-uart.2", .parent = &clk_p, .enable = s3c2412_clkcon_enable, .ctrlbit = S3C2412_CLKCON_UART2, }, { .name = "rtc", .parent = &clk_p, .enable = s3c2412_clkcon_enable, .ctrlbit = S3C2412_CLKCON_RTC, }, { .name = "watchdog", .parent = &clk_p, .ctrlbit = 0, }, { .name = "usb-bus-gadget", .parent = &clk_usb_bus, .enable = s3c2412_clkcon_enable, .ctrlbit = S3C2412_CLKCON_USB_DEV48, }, { .name = "usb-bus-host", .parent = &clk_usb_bus, .enable = s3c2412_clkcon_enable, .ctrlbit = S3C2412_CLKCON_USB_HOST48, } }; /* clocks to add where we need to check their parentage */ struct clk_init { struct clk *clk; unsigned int bit; struct clk *src_0; struct clk *src_1; }; static struct clk_init clks_src[] __initdata = { { .clk = &clk_usysclk, .bit = S3C2412_CLKSRC_USBCLK_HCLK, .src_0 = &clk_urefclk, .src_1 = &clk_upll, }, { .clk = &clk_i2s, .bit = S3C2412_CLKSRC_I2SCLK_MPLL, .src_0 = &clk_erefclk, .src_1 = &clk_mpll, }, { .clk = &clk_cam, .bit = S3C2412_CLKSRC_CAMCLK_HCLK, .src_0 = &clk_usysclk, .src_1 = &clk_h, }, { .clk = &clk_msysclk, .bit = S3C2412_CLKSRC_MSYSCLK_MPLL, .src_0 = &clk_mdivclk, .src_1 = &clk_mpll, }, { .clk = &clk_uart, .bit = S3C2412_CLKSRC_UARTCLK_MPLL, .src_0 = &clk_erefclk, .src_1 = &clk_mpll, }, { .clk = &clk_usbsrc, .bit = S3C2412_CLKSRC_USBCLK_HCLK, .src_0 = &clk_usysclk, .src_1 = &clk_h, /* here we assume OM[4] select xtal */ }, { .clk = &clk_erefclk, .bit = S3C2412_CLKSRC_EREFCLK_EXTCLK, .src_0 = &clk_xtal, .src_1 = &clk_ext, }, { .clk = &clk_urefclk, .bit = S3C2412_CLKSRC_UREFCLK_EXTCLK, .src_0 = &clk_xtal, .src_1 = &clk_ext, }, }; /* s3c2412_clk_initparents * * Initialise the parents for the clocks that we get at start-time */ static void __init s3c2412_clk_initparents(void) { unsigned long clksrc = __raw_readl(S3C2412_CLKSRC); struct clk_init *cip = clks_src; struct clk *src; int ptr; int ret; for (ptr = 0; ptr < ARRAY_SIZE(clks_src); ptr++, cip++) { ret = s3c24xx_register_clock(cip->clk); if (ret < 0) { printk(KERN_ERR "Failed to register clock %s (%d)\n", cip->clk->name, ret); } src = (clksrc & cip->bit) ? cip->src_1 : cip->src_0; printk(KERN_INFO "%s: parent %s\n", cip->clk->name, src->name); clk_set_parent(cip->clk, src); } } /* clocks to add straight away */ static struct clk *clks[] __initdata = { &clk_ext, &clk_usb_bus, &clk_mrefclk, &clk_armclk, }; static struct clk_lookup s3c2412_clk_lookup[] = { CLKDEV_INIT(NULL, "clk_uart_baud1", &s3c24xx_uclk), CLKDEV_INIT(NULL, "clk_uart_baud2", &clk_p), CLKDEV_INIT(NULL, "clk_uart_baud3", &clk_usysclk), }; int __init s3c2412_baseclk_add(void) { unsigned long clkcon = __raw_readl(S3C2410_CLKCON); unsigned int dvs; struct clk *clkp; int ret; int ptr; clk_upll.enable = s3c2412_upll_enable; clk_usb_bus.parent = &clk_usbsrc; clk_usb_bus.rate = 0x0; clk_f.parent = &clk_msysclk; s3c2412_clk_initparents(); for (ptr = 0; ptr < ARRAY_SIZE(clks); ptr++) { clkp = clks[ptr]; ret = s3c24xx_register_clock(clkp); if (ret < 0) { printk(KERN_ERR "Failed to register clock %s (%d)\n", clkp->name, ret); } } /* set the dvs state according to what we got at boot time */ dvs = __raw_readl(S3C2410_CLKDIVN) & S3C2412_CLKDIVN_DVSEN; if (dvs) clk_armclk.parent = &clk_h; printk(KERN_INFO "S3C2412: DVS is %s\n", dvs ? "on" : "off"); /* ensure usb bus clock is within correct rate of 48MHz */ if (clk_get_rate(&clk_usb_bus) != (48 * 1000 * 1000)) { printk(KERN_INFO "Warning: USB bus clock not at 48MHz\n"); /* for the moment, let's use the UPLL, and see if we can * get 48MHz */ clk_set_parent(&clk_usysclk, &clk_upll); clk_set_parent(&clk_usbsrc, &clk_usysclk); clk_set_rate(&clk_usbsrc, 48*1000*1000); } printk("S3C2412: upll %s, %ld.%03ld MHz, usb-bus %ld.%03ld MHz\n", (__raw_readl(S3C2410_UPLLCON) & S3C2412_PLLCON_OFF) ? "off":"on", print_mhz(clk_get_rate(&clk_upll)), print_mhz(clk_get_rate(&clk_usb_bus))); /* register clocks from clock array */ clkp = init_clocks; for (ptr = 0; ptr < ARRAY_SIZE(init_clocks); ptr++, clkp++) { /* ensure that we note the clock state */ clkp->usage = clkcon & clkp->ctrlbit ? 1 : 0; ret = s3c24xx_register_clock(clkp); if (ret < 0) { printk(KERN_ERR "Failed to register clock %s (%d)\n", clkp->name, ret); } } /* We must be careful disabling the clocks we are not intending to * be using at boot time, as subsystems such as the LCD which do * their own DMA requests to the bus can cause the system to lockup * if they where in the middle of requesting bus access. * * Disabling the LCD clock if the LCD is active is very dangerous, * and therefore the bootloader should be careful to not enable * the LCD clock if it is not needed. */ /* install (and disable) the clocks we do not need immediately */ clkp = init_clocks_disable; for (ptr = 0; ptr < ARRAY_SIZE(init_clocks_disable); ptr++, clkp++) { ret = s3c24xx_register_clock(clkp); if (ret < 0) { printk(KERN_ERR "Failed to register clock %s (%d)\n", clkp->name, ret); } s3c2412_clkcon_enable(clkp, 0); } clkdev_add_table(s3c2412_clk_lookup, ARRAY_SIZE(s3c2412_clk_lookup)); s3c_pwmclk_init(); return 0; }