diff options
Diffstat (limited to 'drivers/clk/samsung/clk-s3c2412.c')
| -rw-r--r-- | drivers/clk/samsung/clk-s3c2412.c | 305 |
1 files changed, 305 insertions, 0 deletions
diff --git a/drivers/clk/samsung/clk-s3c2412.c b/drivers/clk/samsung/clk-s3c2412.c new file mode 100644 index 000000000..2ceedaf8c --- /dev/null +++ b/drivers/clk/samsung/clk-s3c2412.c @@ -0,0 +1,305 @@ +/* + * Copyright (c) 2013 Heiko Stuebner <heiko@sntech.de> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * Common Clock Framework support for S3C2412 and S3C2413. + */ + +#include <linux/clk.h> +#include <linux/clkdev.h> +#include <linux/clk-provider.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/syscore_ops.h> +#include <linux/reboot.h> + +#include <dt-bindings/clock/s3c2412.h> + +#include "clk.h" +#include "clk-pll.h" + +#define LOCKTIME 0x00 +#define MPLLCON 0x04 +#define UPLLCON 0x08 +#define CLKCON 0x0c +#define CLKDIVN 0x14 +#define CLKSRC 0x1c +#define SWRST 0x30 + +/* list of PLLs to be registered */ +enum s3c2412_plls { + mpll, upll, +}; + +static void __iomem *reg_base; + +#ifdef CONFIG_PM_SLEEP +static struct samsung_clk_reg_dump *s3c2412_save; + +/* + * list of controller registers to be saved and restored during a + * suspend/resume cycle. + */ +static unsigned long s3c2412_clk_regs[] __initdata = { + LOCKTIME, + MPLLCON, + UPLLCON, + CLKCON, + CLKDIVN, + CLKSRC, +}; + +static int s3c2412_clk_suspend(void) +{ + samsung_clk_save(reg_base, s3c2412_save, + ARRAY_SIZE(s3c2412_clk_regs)); + + return 0; +} + +static void s3c2412_clk_resume(void) +{ + samsung_clk_restore(reg_base, s3c2412_save, + ARRAY_SIZE(s3c2412_clk_regs)); +} + +static struct syscore_ops s3c2412_clk_syscore_ops = { + .suspend = s3c2412_clk_suspend, + .resume = s3c2412_clk_resume, +}; + +static void s3c2412_clk_sleep_init(void) +{ + s3c2412_save = samsung_clk_alloc_reg_dump(s3c2412_clk_regs, + ARRAY_SIZE(s3c2412_clk_regs)); + if (!s3c2412_save) { + pr_warn("%s: failed to allocate sleep save data, no sleep support!\n", + __func__); + return; + } + + register_syscore_ops(&s3c2412_clk_syscore_ops); + return; +} +#else +static void s3c2412_clk_sleep_init(void) {} +#endif + +static struct clk_div_table divxti_d[] = { + { .val = 0, .div = 1 }, + { .val = 1, .div = 2 }, + { .val = 2, .div = 4 }, + { .val = 3, .div = 6 }, + { .val = 4, .div = 8 }, + { .val = 5, .div = 10 }, + { .val = 6, .div = 12 }, + { .val = 7, .div = 14 }, + { /* sentinel */ }, +}; + +struct samsung_div_clock s3c2412_dividers[] __initdata = { + DIV_T(0, "div_xti", "xti", CLKSRC, 0, 3, divxti_d), + DIV(0, "div_cam", "mux_cam", CLKDIVN, 16, 4), + DIV(0, "div_i2s", "mux_i2s", CLKDIVN, 12, 4), + DIV(0, "div_uart", "mux_uart", CLKDIVN, 8, 4), + DIV(0, "div_usb", "mux_usb", CLKDIVN, 6, 1), + DIV(0, "div_hclk_half", "hclk", CLKDIVN, 5, 1), + DIV(ARMDIV, "armdiv", "msysclk", CLKDIVN, 3, 1), + DIV(PCLK, "pclk", "hclk", CLKDIVN, 2, 1), + DIV(HCLK, "hclk", "armdiv", CLKDIVN, 0, 2), +}; + +struct samsung_fixed_factor_clock s3c2412_ffactor[] __initdata = { + FFACTOR(0, "ff_hclk", "hclk", 2, 1, CLK_SET_RATE_PARENT), +}; + +/* + * The first two use the OM[4] setting, which is not readable from + * software, so assume it is set to xti. + */ +PNAME(erefclk_p) = { "xti", "xti", "xti", "ext" }; +PNAME(urefclk_p) = { "xti", "xti", "xti", "ext" }; + +PNAME(camclk_p) = { "usysclk", "hclk" }; +PNAME(usbclk_p) = { "usysclk", "hclk" }; +PNAME(i2sclk_p) = { "erefclk", "mpll" }; +PNAME(uartclk_p) = { "erefclk", "mpll" }; +PNAME(usysclk_p) = { "urefclk", "upll" }; +PNAME(msysclk_p) = { "mdivclk", "mpll" }; +PNAME(mdivclk_p) = { "xti", "div_xti" }; +PNAME(armclk_p) = { "armdiv", "hclk" }; + +struct samsung_mux_clock s3c2412_muxes[] __initdata = { + MUX(0, "erefclk", erefclk_p, CLKSRC, 14, 2), + MUX(0, "urefclk", urefclk_p, CLKSRC, 12, 2), + MUX(0, "mux_cam", camclk_p, CLKSRC, 11, 1), + MUX(0, "mux_usb", usbclk_p, CLKSRC, 10, 1), + MUX(0, "mux_i2s", i2sclk_p, CLKSRC, 9, 1), + MUX(0, "mux_uart", uartclk_p, CLKSRC, 8, 1), + MUX(USYSCLK, "usysclk", usysclk_p, CLKSRC, 5, 1), + MUX(MSYSCLK, "msysclk", msysclk_p, CLKSRC, 4, 1), + MUX(MDIVCLK, "mdivclk", mdivclk_p, CLKSRC, 3, 1), + MUX(ARMCLK, "armclk", armclk_p, CLKDIVN, 4, 1), +}; + +static struct samsung_pll_clock s3c2412_plls[] __initdata = { + [mpll] = PLL(pll_s3c2440_mpll, MPLL, "mpll", "xti", + LOCKTIME, MPLLCON, NULL), + [upll] = PLL(pll_s3c2410_upll, UPLL, "upll", "urefclk", + LOCKTIME, UPLLCON, NULL), +}; + +struct samsung_gate_clock s3c2412_gates[] __initdata = { + GATE(PCLK_WDT, "wdt", "pclk", CLKCON, 28, 0, 0), + GATE(PCLK_SPI, "spi", "pclk", CLKCON, 27, 0, 0), + GATE(PCLK_I2S, "i2s", "pclk", CLKCON, 26, 0, 0), + GATE(PCLK_I2C, "i2c", "pclk", CLKCON, 25, 0, 0), + GATE(PCLK_ADC, "adc", "pclk", CLKCON, 24, 0, 0), + GATE(PCLK_RTC, "rtc", "pclk", CLKCON, 23, 0, 0), + GATE(PCLK_GPIO, "gpio", "pclk", CLKCON, 22, CLK_IGNORE_UNUSED, 0), + GATE(PCLK_UART2, "uart2", "pclk", CLKCON, 21, 0, 0), + GATE(PCLK_UART1, "uart1", "pclk", CLKCON, 20, 0, 0), + GATE(PCLK_UART0, "uart0", "pclk", CLKCON, 19, 0, 0), + GATE(PCLK_SDI, "sdi", "pclk", CLKCON, 18, 0, 0), + GATE(PCLK_PWM, "pwm", "pclk", CLKCON, 17, 0, 0), + GATE(PCLK_USBD, "usb-device", "pclk", CLKCON, 16, 0, 0), + GATE(SCLK_CAM, "sclk_cam", "div_cam", CLKCON, 15, 0, 0), + GATE(SCLK_UART, "sclk_uart", "div_uart", CLKCON, 14, 0, 0), + GATE(SCLK_I2S, "sclk_i2s", "div_i2s", CLKCON, 13, 0, 0), + GATE(SCLK_USBH, "sclk_usbh", "div_usb", CLKCON, 12, 0, 0), + GATE(SCLK_USBD, "sclk_usbd", "div_usb", CLKCON, 11, 0, 0), + GATE(HCLK_HALF, "hclk_half", "div_hclk_half", CLKCON, 10, CLK_IGNORE_UNUSED, 0), + GATE(HCLK_X2, "hclkx2", "ff_hclk", CLKCON, 9, CLK_IGNORE_UNUSED, 0), + GATE(HCLK_SDRAM, "sdram", "hclk", CLKCON, 8, CLK_IGNORE_UNUSED, 0), + GATE(HCLK_USBH, "usb-host", "hclk", CLKCON, 6, 0, 0), + GATE(HCLK_LCD, "lcd", "hclk", CLKCON, 5, 0, 0), + GATE(HCLK_NAND, "nand", "hclk", CLKCON, 4, 0, 0), + GATE(HCLK_DMA3, "dma3", "hclk", CLKCON, 3, CLK_IGNORE_UNUSED, 0), + GATE(HCLK_DMA2, "dma2", "hclk", CLKCON, 2, CLK_IGNORE_UNUSED, 0), + GATE(HCLK_DMA1, "dma1", "hclk", CLKCON, 1, CLK_IGNORE_UNUSED, 0), + GATE(HCLK_DMA0, "dma0", "hclk", CLKCON, 0, CLK_IGNORE_UNUSED, 0), +}; + +struct samsung_clock_alias s3c2412_aliases[] __initdata = { + ALIAS(PCLK_UART0, "s3c2412-uart.0", "uart"), + ALIAS(PCLK_UART1, "s3c2412-uart.1", "uart"), + ALIAS(PCLK_UART2, "s3c2412-uart.2", "uart"), + ALIAS(PCLK_UART0, "s3c2412-uart.0", "clk_uart_baud2"), + ALIAS(PCLK_UART1, "s3c2412-uart.1", "clk_uart_baud2"), + ALIAS(PCLK_UART2, "s3c2412-uart.2", "clk_uart_baud2"), + ALIAS(SCLK_UART, NULL, "clk_uart_baud3"), + ALIAS(PCLK_I2C, "s3c2410-i2c.0", "i2c"), + ALIAS(PCLK_ADC, NULL, "adc"), + ALIAS(PCLK_RTC, NULL, "rtc"), + ALIAS(PCLK_PWM, NULL, "timers"), + ALIAS(HCLK_LCD, NULL, "lcd"), + ALIAS(PCLK_USBD, NULL, "usb-device"), + ALIAS(SCLK_USBD, NULL, "usb-bus-gadget"), + ALIAS(HCLK_USBH, NULL, "usb-host"), + ALIAS(SCLK_USBH, NULL, "usb-bus-host"), + ALIAS(ARMCLK, NULL, "armclk"), + ALIAS(HCLK, NULL, "hclk"), + ALIAS(MPLL, NULL, "mpll"), + ALIAS(MSYSCLK, NULL, "fclk"), +}; + +static int s3c2412_restart(struct notifier_block *this, + unsigned long mode, void *cmd) +{ + /* errata "Watch-dog/Software Reset Problem" specifies that + * this reset must be done with the SYSCLK sourced from + * EXTCLK instead of FOUT to avoid a glitch in the reset + * mechanism. + * + * See the watchdog section of the S3C2412 manual for more + * information on this fix. + */ + + __raw_writel(0x00, reg_base + CLKSRC); + __raw_writel(0x533C2412, reg_base + SWRST); + return NOTIFY_DONE; +} + +static struct notifier_block s3c2412_restart_handler = { + .notifier_call = s3c2412_restart, + .priority = 129, +}; + +/* + * fixed rate clocks generated outside the soc + * Only necessary until the devicetree-move is complete + */ +#define XTI 1 +struct samsung_fixed_rate_clock s3c2412_common_frate_clks[] __initdata = { + FRATE(XTI, "xti", NULL, CLK_IS_ROOT, 0), + FRATE(0, "ext", NULL, CLK_IS_ROOT, 0), +}; + +static void __init s3c2412_common_clk_register_fixed_ext( + struct samsung_clk_provider *ctx, + unsigned long xti_f, unsigned long ext_f) +{ + /* xtal alias is necessary for the current cpufreq driver */ + struct samsung_clock_alias xti_alias = ALIAS(XTI, NULL, "xtal"); + + s3c2412_common_frate_clks[0].fixed_rate = xti_f; + s3c2412_common_frate_clks[1].fixed_rate = ext_f; + samsung_clk_register_fixed_rate(ctx, s3c2412_common_frate_clks, + ARRAY_SIZE(s3c2412_common_frate_clks)); + + samsung_clk_register_alias(ctx, &xti_alias, 1); +} + +void __init s3c2412_common_clk_init(struct device_node *np, unsigned long xti_f, + unsigned long ext_f, void __iomem *base) +{ + struct samsung_clk_provider *ctx; + int ret; + reg_base = base; + + if (np) { + reg_base = of_iomap(np, 0); + if (!reg_base) + panic("%s: failed to map registers\n", __func__); + } + + ctx = samsung_clk_init(np, reg_base, NR_CLKS); + if (!ctx) + panic("%s: unable to allocate context.\n", __func__); + + /* Register external clocks only in non-dt cases */ + if (!np) + s3c2412_common_clk_register_fixed_ext(ctx, xti_f, ext_f); + + /* Register PLLs. */ + samsung_clk_register_pll(ctx, s3c2412_plls, ARRAY_SIZE(s3c2412_plls), + reg_base); + + /* Register common internal clocks. */ + samsung_clk_register_mux(ctx, s3c2412_muxes, ARRAY_SIZE(s3c2412_muxes)); + samsung_clk_register_div(ctx, s3c2412_dividers, + ARRAY_SIZE(s3c2412_dividers)); + samsung_clk_register_gate(ctx, s3c2412_gates, + ARRAY_SIZE(s3c2412_gates)); + samsung_clk_register_fixed_factor(ctx, s3c2412_ffactor, + ARRAY_SIZE(s3c2412_ffactor)); + samsung_clk_register_alias(ctx, s3c2412_aliases, + ARRAY_SIZE(s3c2412_aliases)); + + s3c2412_clk_sleep_init(); + + samsung_clk_of_add_provider(np, ctx); + + ret = register_restart_handler(&s3c2412_restart_handler); + if (ret) + pr_warn("cannot register restart handler, %d\n", ret); +} + +static void __init s3c2412_clk_init(struct device_node *np) +{ + s3c2412_common_clk_init(np, 0, 0, 0); +} +CLK_OF_DECLARE(s3c2412_clk, "samsung,s3c2412-clock", s3c2412_clk_init); |