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path: root/drivers/clk/samsung/clk-s3c2412.c
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-rw-r--r--drivers/clk/samsung/clk-s3c2412.c305
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);