kernel_optimize_test/drivers/clk/samsung/clk-s3c2412.c
Sylwester Nawrocki d5e136a21b clk: samsung: Register clk provider only after registering its all clocks
Ensure the clock provider is not registered until after all its related
clocks were created and are ready to use. Currently there are races
possible and any (of_)clk_get() call right after a clock provider's
clk_init_cb callback call may fail.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Tomasz Figa <t.figa@samsung.com>
2014-06-30 15:07:55 +02:00

277 lines
8.6 KiB
C

/*
* 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 <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
/* 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"),
};
/*
* 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;
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);
}
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);