From: Jongpill Lee <[email protected]> This patch addes system timer for Samsung S5P series SoCs
Signed-off-by: Jongpill Lee <[email protected]> Signed-off-by: Kukjin Kim <[email protected]> --- arch/arm/mach-s5p6442/include/mach/tick.h | 6 + arch/arm/mach-s5p6442/mach-smdk6442.c | 2 +- arch/arm/mach-s5pv210/include/mach/tick.h | 6 + arch/arm/mach-s5pv210/mach-smdkv210.c | 2 +- arch/arm/plat-s5p/Kconfig | 7 + arch/arm/plat-s5p/Makefile | 1 + arch/arm/plat-s5p/include/plat/regs-systimer.h | 75 ++++++ arch/arm/plat-s5p/systimer-s5p.c | 298 ++++++++++++++++++++++++ arch/arm/plat-samsung/include/plat/cpu.h | 3 + 9 files changed, 398 insertions(+), 2 deletions(-) create mode 100644 arch/arm/plat-s5p/include/plat/regs-systimer.h create mode 100644 arch/arm/plat-s5p/systimer-s5p.c diff --git a/arch/arm/mach-s5p6442/include/mach/tick.h b/arch/arm/mach-s5p6442/include/mach/tick.h index e1d4cab..1795b43 100644 --- a/arch/arm/mach-s5p6442/include/mach/tick.h +++ b/arch/arm/mach-s5p6442/include/mach/tick.h @@ -21,6 +21,12 @@ static inline u32 s3c24xx_ostimer_pending(void) return pend & (1 << (IRQ_TIMER4_VIC - S5P_IRQ_VIC0(0))); } +static inline u32 s5p_ostimer_pending(void) +{ + u32 pend = __raw_readl(VA_VIC0 + VIC_RAW_STATUS); + return pend & (1 << (IRQ_SYSTIMER - S5P_IRQ_VIC0(0))); +} + #define TICK_MAX (0xffffffff) #endif /* __ASM_ARCH_TICK_H */ diff --git a/arch/arm/mach-s5p6442/mach-smdk6442.c b/arch/arm/mach-s5p6442/mach-smdk6442.c index 0d63371..825df9d 100644 --- a/arch/arm/mach-s5p6442/mach-smdk6442.c +++ b/arch/arm/mach-s5p6442/mach-smdk6442.c @@ -87,5 +87,5 @@ MACHINE_START(SMDK6442, "SMDK6442") .init_irq = s5p6442_init_irq, .map_io = smdk6442_map_io, .init_machine = smdk6442_machine_init, - .timer = &s3c24xx_timer, + .timer = &s5p_systimer, MACHINE_END diff --git a/arch/arm/mach-s5pv210/include/mach/tick.h b/arch/arm/mach-s5pv210/include/mach/tick.h index 7993b36..9fc5a8d 100644 --- a/arch/arm/mach-s5pv210/include/mach/tick.h +++ b/arch/arm/mach-s5pv210/include/mach/tick.h @@ -21,6 +21,12 @@ static inline u32 s3c24xx_ostimer_pending(void) return pend & (1 << (IRQ_TIMER4_VIC - S5P_IRQ_VIC0(0))); } +static inline u32 s5p_ostimer_pending(void) +{ + u32 pend = __raw_readl(VA_VIC0 + VIC_RAW_STATUS); + return pend & (1 << (IRQ_SYSTIMER - S5P_IRQ_VIC0(0))); +} + #define TICK_MAX (0xffffffff) #endif /* __ASM_ARCH_TICK_H */ diff --git a/arch/arm/mach-s5pv210/mach-smdkv210.c b/arch/arm/mach-s5pv210/mach-smdkv210.c index a278832..22ed209 100644 --- a/arch/arm/mach-s5pv210/mach-smdkv210.c +++ b/arch/arm/mach-s5pv210/mach-smdkv210.c @@ -94,5 +94,5 @@ MACHINE_START(SMDKV210, "SMDKV210") .init_irq = s5pv210_init_irq, .map_io = smdkv210_map_io, .init_machine = smdkv210_machine_init, - .timer = &s3c24xx_timer, + .timer = &s5p_systimer, MACHINE_END diff --git a/arch/arm/plat-s5p/Kconfig b/arch/arm/plat-s5p/Kconfig index d400a6a..a73fc56 100644 --- a/arch/arm/plat-s5p/Kconfig +++ b/arch/arm/plat-s5p/Kconfig @@ -23,3 +23,10 @@ config PLAT_S5P select SAMSUNG_IRQ_UART help Base platform code for Samsung's S5P series SoC. + +config SYSTIMER_S5P + bool + depends on (ARCH_S5P6442 || ARCH_S5PV210) + default y + help + Support System Timer for S5P Series diff --git a/arch/arm/plat-s5p/Makefile b/arch/arm/plat-s5p/Makefile index a7c54b3..ec28f1b 100644 --- a/arch/arm/plat-s5p/Makefile +++ b/arch/arm/plat-s5p/Makefile @@ -17,3 +17,4 @@ obj-y += cpu.o obj-y += clock.o obj-y += irq.o obj-y += setup-i2c0.o +obj-$(CONFIG_SYSTIMER_S5P) += systimer-s5p.o diff --git a/arch/arm/plat-s5p/include/plat/regs-systimer.h b/arch/arm/plat-s5p/include/plat/regs-systimer.h new file mode 100644 index 0000000..937ec44 --- /dev/null +++ b/arch/arm/plat-s5p/include/plat/regs-systimer.h @@ -0,0 +1,75 @@ +/* linux/arch/arm/plat-s5p/include/plat/regs-systimer.h + * + * Copyright (c) 2010 Samsung Electronics Co., Ltd. + * http://www.samsung.com/ + * + * S5P System Timer Driver Header information + * + * 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. +*/ + +#ifndef __ASM_PLAT_REGS_SYSTIMER_H +#define __ASM_PLAT_REGS_SYSTIMER_H __FILE__ + +#define S5P_SYSTIMERREG(x) (S5P_VA_SYSTIMER + (x)) + +#define S5P_SYSTIMER_TCFG S5P_SYSTIMERREG(0x00) +#define S5P_SYSTIMER_TCON S5P_SYSTIMERREG(0x04) +#define S5P_SYSTIMER_TICNTB S5P_SYSTIMERREG(0x08) +#define S5P_SYSTIMER_TICNTO S5P_SYSTIMERREG(0x0c) +#define S5P_SYSTIMER_TFCNTB S5P_SYSTIMERREG(0x10) +#define S5P_SYSTIMER_ICNTB S5P_SYSTIMERREG(0x18) +#define S5P_SYSTIMER_ICNTO S5P_SYSTIMERREG(0x1c) +#define S5P_SYSTIMER_INT_CSTAT S5P_SYSTIMERREG(0x20) + +/* Value for TCFG */ + +#define S5P_SYSTIMER_SWRST (1<<16) + +#define S5P_SYSTIMER_DIV_GEN (0<<15) +#define S5P_SYSTIMER_DIV_RTC (1<<15) + +#define S5P_SYSTIMER_TICK_INT (0<<14) +#define S5P_SYSTIMER_TICK_FRA (1<<14) + +#define S5P_SYSTIMER_TCLK_MASK (3<<12) +#define S5P_SYSTIMER_TCLK_XXTI (0<<12) +#define S5P_SYSTIMER_TCLK_RTC (1<<12) +#define S5P_SYSTIMER_TCLK_USB (2<<12) +#define S5P_SYSTIMER_TCLK_PCLK (3<<12) + +#define S5P_SYSTIMER_DIV_MASK (7<<8) +#define S5P_SYSTIMER_DIV_1 (0<<8) +#define S5P_SYSTIMER_DIV_2 (1<<8) +#define S5P_SYSTIMER_DIV_4 (2<<8) +#define S5P_SYSTIMER_DIV_8 (3<<8) +#define S5P_SYSTIMER_DIV_16 (4<<8) + +#define S5P_SYSTIMER_TARGET_HZ 1000 +#define S5P_SYSTIMER_PRESCALER 5 +#define S5P_SYSTIMER_PRESCALER_MASK (0x3f<<0) + +/* value for TCON */ + +#define S5P_SYSTIMER_INT_AUTO (1<<5) +#define S5P_SYSTIMER_INT_IMM (1<<4) +#define S5P_SYSTIMER_INT_START (1<<3) +#define S5P_SYSTIMER_START (1<<0) + +/* Value for INT_CSTAT */ + +#define S5P_SYSTIMER_INT_TWIE (1<<10) +#define S5P_SYSTIMER_INT_IWIE (1<<9) +#define S5P_SYSTIMER_INT_TFWIE (1<<8) +#define S5P_SYSTIMER_INT_TIWIE (1<<7) +#define S5P_SYSTIMER_INT_ICNTEIE (1<<6) +#define S5P_SYSTIMER_INT_TCON (1<<5) +#define S5P_SYSTIMER_INT_ICNTB (1<<4) +#define S5P_SYSTIMER_INT_TFCNTB (1<<3) +#define S5P_SYSTIMER_INT_TICNTB (1<<2) +#define S5P_SYSTIMER_INT_INTCNT (1<<1) +#define S5P_SYSTIMER_INT_INTENABLE (1<<0) + +#endif /* __ASM_PLAT_REGS_SYSTIMER_H */ diff --git a/arch/arm/plat-s5p/systimer-s5p.c b/arch/arm/plat-s5p/systimer-s5p.c new file mode 100644 index 0000000..66951c8 --- /dev/null +++ b/arch/arm/plat-s5p/systimer-s5p.c @@ -0,0 +1,298 @@ +/* linux/arch/arm/plat-s5p/systimer-s5p.c + * + * Copyright (c) 2010 Samsung Electronics Co., Ltd. + * http://www.samsung.com/ + * + * S5P System Timer + * + * Based on linux/arch/arm/plat-samsung/time.c + * + * 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. +*/ + +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/init.h> +#include <linux/errno.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/err.h> +#include <linux/clk.h> +#include <linux/io.h> + +#include <asm/system.h> +#include <asm/mach-types.h> + +#include <asm/irq.h> +#include <asm/mach/time.h> + +#include <mach/map.h> +#include <mach/regs-irq.h> +#include <mach/tick.h> + +#include <plat/regs-systimer.h> +#include <plat/clock.h> +#include <plat/cpu.h> + +#include <mach/regs-clock.h> + +static unsigned long timer_startval; +static unsigned long timer_usec_ticks; +static unsigned long timer_icnt; + +#define TICK_MAX (0xffffffff) +#define TIMER_USEC_SHIFT 16 + +static unsigned int systimer_write_done(unsigned int value) +{ + unsigned int cnt; + unsigned int tmp_reg; + + cnt = 1000; + + do { + cnt--; + + if (__raw_readl(S5P_SYSTIMER_INT_CSTAT) & value) { + tmp_reg = __raw_readl(S5P_SYSTIMER_INT_CSTAT); + tmp_reg |= value; + __raw_writel(tmp_reg , S5P_SYSTIMER_INT_CSTAT); + + return 0; + } + + } while (cnt > 0); + + printk(KERN_ERR "%s : %d : Timer Expired\n", __func__, value); + + return -ETIME; +} + +static unsigned int s5p_systimer_write(void __iomem *reg_offset, + unsigned int value) +{ + unsigned int int_cstat; + unsigned int ret = 0; + + int_cstat = __raw_readl(S5P_SYSTIMER_INT_CSTAT); + + if (reg_offset == S5P_SYSTIMER_TCON) { + __raw_writel(value, reg_offset); + + if (int_cstat & S5P_SYSTIMER_INT_TWIE) + ret = systimer_write_done(S5P_SYSTIMER_INT_TCON); + + } else if (reg_offset == S5P_SYSTIMER_ICNTB) { + __raw_writel(value, reg_offset); + + if (int_cstat & S5P_SYSTIMER_INT_IWIE) + ret = systimer_write_done(S5P_SYSTIMER_INT_ICNTB); + + } else if (reg_offset == S5P_SYSTIMER_TFCNTB) { + __raw_writel(value, reg_offset); + + if (int_cstat & S5P_SYSTIMER_INT_TFWIE) + ret = systimer_write_done(S5P_SYSTIMER_INT_TFCNTB); + + } else if (reg_offset == S5P_SYSTIMER_TICNTB) { + __raw_writel(value, reg_offset); + + if (int_cstat & S5P_SYSTIMER_INT_TIWIE) + ret = systimer_write_done(S5P_SYSTIMER_INT_TICNTB); + } else { + __raw_writel(value, reg_offset); + } + + return ret; +} + +/* + * S5P has system timer to use as OS tick Timer. + * System Timer provides two distincive feature. Accurate timer which provides + * exact 1ms time tick at any power mode except sleep mode. + * interrupt interval without stopping reference tick timer. + */ + +/* + * timer_mask_usec_ticks + * + * given a clock and divisor, make the value to pass into timer_ticks_to_usec + * to scale the ticks into usecs + */ +static inline unsigned long timer_mask_usec_ticks(unsigned long scaler, + unsigned long pclk) +{ + unsigned long den = pclk / 1000; + + return ((1000 << TIMER_USEC_SHIFT) * scaler + (den >> 1)) / den; +} + +/* + * timer_ticks_to_usec + * + * convert timer ticks to usec. + */ +static inline unsigned long timer_ticks_to_usec(unsigned long ticks) +{ + unsigned long res; + + res = ticks * timer_usec_ticks; + res += 1 << (TIMER_USEC_SHIFT - 4); /* round up slightly */ + + return res >> TIMER_USEC_SHIFT; +} + +/* + * Returns microsecond since last clock interrupt. Note that interrupts + * will have been disabled by do_gettimeoffset() + * IRQs are disabled before entering here from do_gettimeofday() + */ +static unsigned long s5p_gettimeoffset(void) +{ + unsigned long tdone; + unsigned long tval; + unsigned long clk_tick_totcnt; + + clk_tick_totcnt = (timer_icnt + 1) * timer_startval; + + /* work out how many ticks have gone since last timer interrupt */ + tval = __raw_readl(S5P_SYSTIMER_ICNTO) * timer_startval; + tval += __raw_readl(S5P_SYSTIMER_TICNTO); + + tdone = clk_tick_totcnt - tval; + + /* check to see if there is an interrupt pending */ + if (s5p_ostimer_pending()) { + /* re-read the timer, and try and fix up for the missed + * interrupt. Note, the interrupt may go off before the + * timer has re-loaded from wrapping. + */ + + tval = __raw_readl(S5P_SYSTIMER_ICNTO) * timer_startval; + tval += __raw_readl(S5P_SYSTIMER_TICNTO); + + tdone = clk_tick_totcnt - tval; + + if (tval != 0) + tdone += clk_tick_totcnt; + } + + return timer_ticks_to_usec(tdone); +} + +/* + * IRQ handler for the timer + */ +static irqreturn_t s5p_systimer_interrupt(int irq, void *dev_id) +{ + unsigned int temp_cstat; + + temp_cstat = __raw_readl(S5P_SYSTIMER_INT_CSTAT); + temp_cstat |= S5P_SYSTIMER_INT_INTCNT; + s5p_systimer_write(S5P_SYSTIMER_INT_CSTAT, temp_cstat); + + timer_tick(); + + return IRQ_HANDLED; +} + +static struct irqaction s5p_systimer_irq = { + .name = "S5P System Timer", + .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL, + .handler = s5p_systimer_interrupt, +}; + +/* + * Set up timer interrupt, and return the current time in seconds. + */ +static void s5p_systimer_setup(void) +{ + unsigned long tcon; + unsigned long tcnt; + unsigned long tcfg; + unsigned long int_csata; + + /* clock configuration setting and enable */ + unsigned long pclk; + struct clk *clk; + + clk = clk_get(NULL, "systimer"); + if (IS_ERR(clk)) + panic("failed to get clock for system timer"); + + clk_enable(clk); + + pclk = clk_get_rate(clk); + + tcfg = __raw_readl(S5P_SYSTIMER_TCFG); + tcfg |= S5P_SYSTIMER_SWRST; + s5p_systimer_write(S5P_SYSTIMER_TCFG, tcfg); + + tcnt = TICK_MAX; /* default value for tcnt */ + + /* initialize system timer clock */ + tcfg = __raw_readl(S5P_SYSTIMER_TCFG); + + tcfg &= ~S5P_SYSTIMER_TCLK_MASK; + tcfg |= S5P_SYSTIMER_TCLK_PCLK; + + s5p_systimer_write(S5P_SYSTIMER_TCFG, tcfg); + + /* TCFG must not be changed at run-time. + * If you want to change TCFG, stop timer(TCON[0] = 0) + */ + + s5p_systimer_write(S5P_SYSTIMER_TCON, 0); + + /* read the current timer configuration bits */ + tcon = __raw_readl(S5P_SYSTIMER_TCON); + tcfg = __raw_readl(S5P_SYSTIMER_TCFG); + + /* configure clock tick */ + timer_usec_ticks = timer_mask_usec_ticks(S5P_SYSTIMER_PRESCALER, pclk); + + tcfg &= ~S5P_SYSTIMER_TCLK_MASK; + tcfg |= S5P_SYSTIMER_TCLK_PCLK; + tcfg &= ~S5P_SYSTIMER_PRESCALER_MASK; + tcfg |= S5P_SYSTIMER_PRESCALER - 1; + + tcnt = ((pclk / S5P_SYSTIMER_PRESCALER) / S5P_SYSTIMER_TARGET_HZ) - 1; + + /* check to see if timer is within 16bit range... */ + if (tcnt > TICK_MAX) { + panic("setup_timer: HZ is too small, cannot configure timer!"); + return; + } + + s5p_systimer_write(S5P_SYSTIMER_TCFG, tcfg); + + timer_startval = tcnt; + s5p_systimer_write(S5P_SYSTIMER_TICNTB, tcnt); + + /* set Interrupt tick value */ + timer_icnt = (S5P_SYSTIMER_TARGET_HZ / HZ) - 1; + s5p_systimer_write(S5P_SYSTIMER_ICNTB, timer_icnt); + + tcon = (S5P_SYSTIMER_INT_AUTO | S5P_SYSTIMER_START + | S5P_SYSTIMER_INT_START); + s5p_systimer_write(S5P_SYSTIMER_TCON, tcon); + + /* Interrupt Start and Enable */ + int_csata = __raw_readl(S5P_SYSTIMER_INT_CSTAT); + int_csata |= (S5P_SYSTIMER_INT_ICNTEIE | S5P_SYSTIMER_INT_INTENABLE); + s5p_systimer_write(S5P_SYSTIMER_INT_CSTAT, int_csata); +} + +static void __init s5p_systimer_init(void) +{ + s5p_systimer_setup(); + setup_irq(IRQ_SYSTIMER, &s5p_systimer_irq); +} + +struct sys_timer s5p_systimer = { + .init = s5p_systimer_init, + .offset = s5p_gettimeoffset, + .resume = s5p_systimer_setup +}; diff --git a/arch/arm/plat-samsung/include/plat/cpu.h b/arch/arm/plat-samsung/include/plat/cpu.h index d316b4a..6baa357 100644 --- a/arch/arm/plat-samsung/include/plat/cpu.h +++ b/arch/arm/plat-samsung/include/plat/cpu.h @@ -68,6 +68,9 @@ extern void s3c24xx_init_uartdevs(char *name, struct sys_timer; extern struct sys_timer s3c24xx_timer; +/* timer for s5p */ +extern struct sys_timer s5p_systimer; + /* system device classes */ extern struct sysdev_class s3c2410_sysclass; -- 1.6.2.5 -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
