mirror of https://gitee.com/openkylin/linux.git
620 lines
16 KiB
C
620 lines
16 KiB
C
/*
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* linux/arch/arm/mach-omap2/timer.c
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*
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* OMAP2 GP timer support.
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*
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* Copyright (C) 2009 Nokia Corporation
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*
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* Update to use new clocksource/clockevent layers
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* Author: Kevin Hilman, MontaVista Software, Inc. <source@mvista.com>
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* Copyright (C) 2007 MontaVista Software, Inc.
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*
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* Original driver:
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* Copyright (C) 2005 Nokia Corporation
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* Author: Paul Mundt <paul.mundt@nokia.com>
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* Juha Yrjölä <juha.yrjola@nokia.com>
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* OMAP Dual-mode timer framework support by Timo Teras
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*
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* Some parts based off of TI's 24xx code:
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*
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* Copyright (C) 2004-2009 Texas Instruments, Inc.
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*
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* Roughly modelled after the OMAP1 MPU timer code.
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* Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
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*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file "COPYING" in the main directory of this archive
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* for more details.
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*/
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#include <linux/init.h>
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#include <linux/time.h>
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#include <linux/interrupt.h>
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#include <linux/err.h>
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#include <linux/clk.h>
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#include <linux/delay.h>
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#include <linux/irq.h>
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#include <linux/clocksource.h>
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#include <linux/clockchips.h>
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#include <linux/slab.h>
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#include <linux/of.h>
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#include <asm/mach/time.h>
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#include <asm/smp_twd.h>
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#include <asm/sched_clock.h>
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#include <asm/arch_timer.h>
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#include <plat/omap_hwmod.h>
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#include <plat/omap_device.h>
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#include <plat/dmtimer.h>
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#include <plat/omap-pm.h>
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#include "soc.h"
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#include "common.h"
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#include "powerdomain.h"
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/* Parent clocks, eventually these will come from the clock framework */
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#define OMAP2_MPU_SOURCE "sys_ck"
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#define OMAP3_MPU_SOURCE OMAP2_MPU_SOURCE
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#define OMAP4_MPU_SOURCE "sys_clkin_ck"
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#define OMAP2_32K_SOURCE "func_32k_ck"
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#define OMAP3_32K_SOURCE "omap_32k_fck"
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#define OMAP4_32K_SOURCE "sys_32k_ck"
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#ifdef CONFIG_OMAP_32K_TIMER
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#define OMAP2_CLKEV_SOURCE OMAP2_32K_SOURCE
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#define OMAP3_CLKEV_SOURCE OMAP3_32K_SOURCE
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#define OMAP4_CLKEV_SOURCE OMAP4_32K_SOURCE
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#define OMAP3_SECURE_TIMER 12
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#else
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#define OMAP2_CLKEV_SOURCE OMAP2_MPU_SOURCE
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#define OMAP3_CLKEV_SOURCE OMAP3_MPU_SOURCE
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#define OMAP4_CLKEV_SOURCE OMAP4_MPU_SOURCE
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#define OMAP3_SECURE_TIMER 1
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#endif
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#define REALTIME_COUNTER_BASE 0x48243200
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#define INCREMENTER_NUMERATOR_OFFSET 0x10
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#define INCREMENTER_DENUMERATOR_RELOAD_OFFSET 0x14
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#define NUMERATOR_DENUMERATOR_MASK 0xfffff000
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/* Clockevent code */
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static struct omap_dm_timer clkev;
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static struct clock_event_device clockevent_gpt;
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static irqreturn_t omap2_gp_timer_interrupt(int irq, void *dev_id)
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{
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struct clock_event_device *evt = &clockevent_gpt;
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__omap_dm_timer_write_status(&clkev, OMAP_TIMER_INT_OVERFLOW);
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evt->event_handler(evt);
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return IRQ_HANDLED;
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}
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static struct irqaction omap2_gp_timer_irq = {
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.name = "gp_timer",
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.flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
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.handler = omap2_gp_timer_interrupt,
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};
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static int omap2_gp_timer_set_next_event(unsigned long cycles,
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struct clock_event_device *evt)
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{
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__omap_dm_timer_load_start(&clkev, OMAP_TIMER_CTRL_ST,
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0xffffffff - cycles, 1);
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return 0;
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}
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static void omap2_gp_timer_set_mode(enum clock_event_mode mode,
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struct clock_event_device *evt)
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{
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u32 period;
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__omap_dm_timer_stop(&clkev, 1, clkev.rate);
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switch (mode) {
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case CLOCK_EVT_MODE_PERIODIC:
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period = clkev.rate / HZ;
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period -= 1;
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/* Looks like we need to first set the load value separately */
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__omap_dm_timer_write(&clkev, OMAP_TIMER_LOAD_REG,
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0xffffffff - period, 1);
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__omap_dm_timer_load_start(&clkev,
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OMAP_TIMER_CTRL_AR | OMAP_TIMER_CTRL_ST,
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0xffffffff - period, 1);
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break;
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case CLOCK_EVT_MODE_ONESHOT:
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break;
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case CLOCK_EVT_MODE_UNUSED:
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case CLOCK_EVT_MODE_SHUTDOWN:
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case CLOCK_EVT_MODE_RESUME:
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break;
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}
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}
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static struct clock_event_device clockevent_gpt = {
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.name = "gp_timer",
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.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
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.shift = 32,
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.rating = 300,
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.set_next_event = omap2_gp_timer_set_next_event,
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.set_mode = omap2_gp_timer_set_mode,
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};
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static int __init omap_dm_timer_init_one(struct omap_dm_timer *timer,
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int gptimer_id,
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const char *fck_source)
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{
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char name[10]; /* 10 = sizeof("gptXX_Xck0") */
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struct omap_hwmod *oh;
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struct resource irq_rsrc, mem_rsrc;
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size_t size;
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int res = 0;
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int r;
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sprintf(name, "timer%d", gptimer_id);
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omap_hwmod_setup_one(name);
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oh = omap_hwmod_lookup(name);
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if (!oh)
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return -ENODEV;
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r = omap_hwmod_get_resource_byname(oh, IORESOURCE_IRQ, NULL, &irq_rsrc);
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if (r)
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return -ENXIO;
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timer->irq = irq_rsrc.start;
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r = omap_hwmod_get_resource_byname(oh, IORESOURCE_MEM, NULL, &mem_rsrc);
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if (r)
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return -ENXIO;
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timer->phys_base = mem_rsrc.start;
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size = mem_rsrc.end - mem_rsrc.start;
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/* Static mapping, never released */
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timer->io_base = ioremap(timer->phys_base, size);
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if (!timer->io_base)
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return -ENXIO;
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/* After the dmtimer is using hwmod these clocks won't be needed */
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timer->fclk = clk_get(NULL, omap_hwmod_get_main_clk(oh));
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if (IS_ERR(timer->fclk))
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return -ENODEV;
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omap_hwmod_enable(oh);
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if (omap_dm_timer_reserve_systimer(gptimer_id))
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return -ENODEV;
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if (gptimer_id != 12) {
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struct clk *src;
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src = clk_get(NULL, fck_source);
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if (IS_ERR(src)) {
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res = -EINVAL;
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} else {
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res = __omap_dm_timer_set_source(timer->fclk, src);
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if (IS_ERR_VALUE(res))
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pr_warning("%s: timer%i cannot set source\n",
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__func__, gptimer_id);
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clk_put(src);
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}
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}
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__omap_dm_timer_init_regs(timer);
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__omap_dm_timer_reset(timer, 1, 1);
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timer->posted = 1;
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timer->rate = clk_get_rate(timer->fclk);
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timer->reserved = 1;
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return res;
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}
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static void __init omap2_gp_clockevent_init(int gptimer_id,
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const char *fck_source)
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{
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int res;
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res = omap_dm_timer_init_one(&clkev, gptimer_id, fck_source);
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BUG_ON(res);
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omap2_gp_timer_irq.dev_id = &clkev;
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setup_irq(clkev.irq, &omap2_gp_timer_irq);
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__omap_dm_timer_int_enable(&clkev, OMAP_TIMER_INT_OVERFLOW);
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clockevent_gpt.mult = div_sc(clkev.rate, NSEC_PER_SEC,
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clockevent_gpt.shift);
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clockevent_gpt.max_delta_ns =
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clockevent_delta2ns(0xffffffff, &clockevent_gpt);
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clockevent_gpt.min_delta_ns =
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clockevent_delta2ns(3, &clockevent_gpt);
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/* Timer internal resynch latency. */
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clockevent_gpt.cpumask = cpu_possible_mask;
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clockevent_gpt.irq = omap_dm_timer_get_irq(&clkev);
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clockevents_register_device(&clockevent_gpt);
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pr_info("OMAP clockevent source: GPTIMER%d at %lu Hz\n",
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gptimer_id, clkev.rate);
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}
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/* Clocksource code */
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static struct omap_dm_timer clksrc;
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static bool use_gptimer_clksrc;
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/*
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* clocksource
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*/
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static cycle_t clocksource_read_cycles(struct clocksource *cs)
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{
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return (cycle_t)__omap_dm_timer_read_counter(&clksrc, 1);
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}
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static struct clocksource clocksource_gpt = {
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.name = "gp_timer",
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.rating = 300,
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.read = clocksource_read_cycles,
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.mask = CLOCKSOURCE_MASK(32),
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.flags = CLOCK_SOURCE_IS_CONTINUOUS,
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};
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static u32 notrace dmtimer_read_sched_clock(void)
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{
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if (clksrc.reserved)
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return __omap_dm_timer_read_counter(&clksrc, 1);
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return 0;
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}
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#ifdef CONFIG_OMAP_32K_TIMER
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/* Setup free-running counter for clocksource */
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static int __init omap2_sync32k_clocksource_init(void)
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{
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int ret;
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struct omap_hwmod *oh;
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void __iomem *vbase;
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const char *oh_name = "counter_32k";
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/*
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* First check hwmod data is available for sync32k counter
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*/
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oh = omap_hwmod_lookup(oh_name);
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if (!oh || oh->slaves_cnt == 0)
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return -ENODEV;
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omap_hwmod_setup_one(oh_name);
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vbase = omap_hwmod_get_mpu_rt_va(oh);
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if (!vbase) {
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pr_warn("%s: failed to get counter_32k resource\n", __func__);
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return -ENXIO;
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}
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ret = omap_hwmod_enable(oh);
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if (ret) {
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pr_warn("%s: failed to enable counter_32k module (%d)\n",
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__func__, ret);
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return ret;
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}
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ret = omap_init_clocksource_32k(vbase);
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if (ret) {
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pr_warn("%s: failed to initialize counter_32k as a clocksource (%d)\n",
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__func__, ret);
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omap_hwmod_idle(oh);
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}
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return ret;
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}
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#else
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static inline int omap2_sync32k_clocksource_init(void)
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{
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return -ENODEV;
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}
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#endif
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static void __init omap2_gptimer_clocksource_init(int gptimer_id,
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const char *fck_source)
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{
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int res;
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res = omap_dm_timer_init_one(&clksrc, gptimer_id, fck_source);
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BUG_ON(res);
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__omap_dm_timer_load_start(&clksrc,
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OMAP_TIMER_CTRL_ST | OMAP_TIMER_CTRL_AR, 0, 1);
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setup_sched_clock(dmtimer_read_sched_clock, 32, clksrc.rate);
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if (clocksource_register_hz(&clocksource_gpt, clksrc.rate))
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pr_err("Could not register clocksource %s\n",
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clocksource_gpt.name);
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else
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pr_info("OMAP clocksource: GPTIMER%d at %lu Hz\n",
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gptimer_id, clksrc.rate);
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}
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static void __init omap2_clocksource_init(int gptimer_id,
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const char *fck_source)
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{
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/*
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* First give preference to kernel parameter configuration
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* by user (clocksource="gp_timer").
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*
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* In case of missing kernel parameter for clocksource,
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* first check for availability for 32k-sync timer, in case
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* of failure in finding 32k_counter module or registering
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* it as clocksource, execution will fallback to gp-timer.
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*/
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if (use_gptimer_clksrc == true)
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omap2_gptimer_clocksource_init(gptimer_id, fck_source);
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else if (omap2_sync32k_clocksource_init())
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/* Fall back to gp-timer code */
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omap2_gptimer_clocksource_init(gptimer_id, fck_source);
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}
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#ifdef CONFIG_SOC_HAS_REALTIME_COUNTER
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/*
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* The realtime counter also called master counter, is a free-running
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* counter, which is related to real time. It produces the count used
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* by the CPU local timer peripherals in the MPU cluster. The timer counts
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* at a rate of 6.144 MHz. Because the device operates on different clocks
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* in different power modes, the master counter shifts operation between
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* clocks, adjusting the increment per clock in hardware accordingly to
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* maintain a constant count rate.
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*/
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static void __init realtime_counter_init(void)
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{
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void __iomem *base;
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static struct clk *sys_clk;
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unsigned long rate;
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unsigned int reg, num, den;
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base = ioremap(REALTIME_COUNTER_BASE, SZ_32);
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if (!base) {
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pr_err("%s: ioremap failed\n", __func__);
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return;
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}
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sys_clk = clk_get(NULL, "sys_clkin_ck");
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if (IS_ERR(sys_clk)) {
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pr_err("%s: failed to get system clock handle\n", __func__);
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iounmap(base);
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return;
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}
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rate = clk_get_rate(sys_clk);
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/* Numerator/denumerator values refer TRM Realtime Counter section */
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switch (rate) {
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case 1200000:
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num = 64;
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den = 125;
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break;
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case 1300000:
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num = 768;
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den = 1625;
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break;
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case 19200000:
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num = 8;
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den = 25;
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break;
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case 2600000:
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num = 384;
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den = 1625;
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break;
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case 2700000:
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num = 256;
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den = 1125;
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break;
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case 38400000:
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default:
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/* Program it for 38.4 MHz */
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num = 4;
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den = 25;
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break;
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}
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/* Program numerator and denumerator registers */
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reg = __raw_readl(base + INCREMENTER_NUMERATOR_OFFSET) &
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NUMERATOR_DENUMERATOR_MASK;
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reg |= num;
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__raw_writel(reg, base + INCREMENTER_NUMERATOR_OFFSET);
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reg = __raw_readl(base + INCREMENTER_NUMERATOR_OFFSET) &
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NUMERATOR_DENUMERATOR_MASK;
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reg |= den;
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__raw_writel(reg, base + INCREMENTER_DENUMERATOR_RELOAD_OFFSET);
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iounmap(base);
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}
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#else
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static inline void __init realtime_counter_init(void)
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{}
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#endif
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#define OMAP_SYS_TIMER_INIT(name, clkev_nr, clkev_src, \
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clksrc_nr, clksrc_src) \
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static void __init omap##name##_timer_init(void) \
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{ \
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omap2_gp_clockevent_init((clkev_nr), clkev_src); \
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omap2_clocksource_init((clksrc_nr), clksrc_src); \
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}
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#define OMAP_SYS_TIMER(name) \
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struct sys_timer omap##name##_timer = { \
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.init = omap##name##_timer_init, \
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};
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#ifdef CONFIG_ARCH_OMAP2
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OMAP_SYS_TIMER_INIT(2, 1, OMAP2_CLKEV_SOURCE, 2, OMAP2_MPU_SOURCE)
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OMAP_SYS_TIMER(2)
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#endif
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#ifdef CONFIG_ARCH_OMAP3
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OMAP_SYS_TIMER_INIT(3, 1, OMAP3_CLKEV_SOURCE, 2, OMAP3_MPU_SOURCE)
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OMAP_SYS_TIMER(3)
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OMAP_SYS_TIMER_INIT(3_secure, OMAP3_SECURE_TIMER, OMAP3_CLKEV_SOURCE,
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2, OMAP3_MPU_SOURCE)
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OMAP_SYS_TIMER(3_secure)
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#endif
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#ifdef CONFIG_SOC_AM33XX
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OMAP_SYS_TIMER_INIT(3_am33xx, 1, OMAP4_MPU_SOURCE, 2, OMAP4_MPU_SOURCE)
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OMAP_SYS_TIMER(3_am33xx)
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#endif
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#ifdef CONFIG_ARCH_OMAP4
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#ifdef CONFIG_LOCAL_TIMERS
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static DEFINE_TWD_LOCAL_TIMER(twd_local_timer,
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OMAP44XX_LOCAL_TWD_BASE, 29 + OMAP_INTC_START);
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#endif
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static void __init omap4_timer_init(void)
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{
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omap2_gp_clockevent_init(1, OMAP4_CLKEV_SOURCE);
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omap2_clocksource_init(2, OMAP4_MPU_SOURCE);
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#ifdef CONFIG_LOCAL_TIMERS
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/* Local timers are not supprted on OMAP4430 ES1.0 */
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if (omap_rev() != OMAP4430_REV_ES1_0) {
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int err;
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if (of_have_populated_dt()) {
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twd_local_timer_of_register();
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return;
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}
|
|
|
|
err = twd_local_timer_register(&twd_local_timer);
|
|
if (err)
|
|
pr_err("twd_local_timer_register failed %d\n", err);
|
|
}
|
|
#endif
|
|
}
|
|
OMAP_SYS_TIMER(4)
|
|
#endif
|
|
|
|
#ifdef CONFIG_SOC_OMAP5
|
|
static void __init omap5_timer_init(void)
|
|
{
|
|
int err;
|
|
|
|
omap2_gp_clockevent_init(1, OMAP4_CLKEV_SOURCE);
|
|
omap2_clocksource_init(2, OMAP4_MPU_SOURCE);
|
|
realtime_counter_init();
|
|
|
|
err = arch_timer_of_register();
|
|
if (err)
|
|
pr_err("%s: arch_timer_register failed %d\n", __func__, err);
|
|
}
|
|
OMAP_SYS_TIMER(5)
|
|
#endif
|
|
|
|
/**
|
|
* omap_timer_init - build and register timer device with an
|
|
* associated timer hwmod
|
|
* @oh: timer hwmod pointer to be used to build timer device
|
|
* @user: parameter that can be passed from calling hwmod API
|
|
*
|
|
* Called by omap_hwmod_for_each_by_class to register each of the timer
|
|
* devices present in the system. The number of timer devices is known
|
|
* by parsing through the hwmod database for a given class name. At the
|
|
* end of function call memory is allocated for timer device and it is
|
|
* registered to the framework ready to be proved by the driver.
|
|
*/
|
|
static int __init omap_timer_init(struct omap_hwmod *oh, void *unused)
|
|
{
|
|
int id;
|
|
int ret = 0;
|
|
char *name = "omap_timer";
|
|
struct dmtimer_platform_data *pdata;
|
|
struct platform_device *pdev;
|
|
struct omap_timer_capability_dev_attr *timer_dev_attr;
|
|
|
|
pr_debug("%s: %s\n", __func__, oh->name);
|
|
|
|
/* on secure device, do not register secure timer */
|
|
timer_dev_attr = oh->dev_attr;
|
|
if (omap_type() != OMAP2_DEVICE_TYPE_GP && timer_dev_attr)
|
|
if (timer_dev_attr->timer_capability == OMAP_TIMER_SECURE)
|
|
return ret;
|
|
|
|
pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
|
|
if (!pdata) {
|
|
pr_err("%s: No memory for [%s]\n", __func__, oh->name);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/*
|
|
* Extract the IDs from name field in hwmod database
|
|
* and use the same for constructing ids' for the
|
|
* timer devices. In a way, we are avoiding usage of
|
|
* static variable witin the function to do the same.
|
|
* CAUTION: We have to be careful and make sure the
|
|
* name in hwmod database does not change in which case
|
|
* we might either make corresponding change here or
|
|
* switch back static variable mechanism.
|
|
*/
|
|
sscanf(oh->name, "timer%2d", &id);
|
|
|
|
if (timer_dev_attr)
|
|
pdata->timer_capability = timer_dev_attr->timer_capability;
|
|
|
|
pdev = omap_device_build(name, id, oh, pdata, sizeof(*pdata),
|
|
NULL, 0, 0);
|
|
|
|
if (IS_ERR(pdev)) {
|
|
pr_err("%s: Can't build omap_device for %s: %s.\n",
|
|
__func__, name, oh->name);
|
|
ret = -EINVAL;
|
|
}
|
|
|
|
kfree(pdata);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* omap2_dm_timer_init - top level regular device initialization
|
|
*
|
|
* Uses dedicated hwmod api to parse through hwmod database for
|
|
* given class name and then build and register the timer device.
|
|
*/
|
|
static int __init omap2_dm_timer_init(void)
|
|
{
|
|
int ret;
|
|
|
|
ret = omap_hwmod_for_each_by_class("timer", omap_timer_init, NULL);
|
|
if (unlikely(ret)) {
|
|
pr_err("%s: device registration failed.\n", __func__);
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
arch_initcall(omap2_dm_timer_init);
|
|
|
|
/**
|
|
* omap2_override_clocksource - clocksource override with user configuration
|
|
*
|
|
* Allows user to override default clocksource, using kernel parameter
|
|
* clocksource="gp_timer" (For all OMAP2PLUS architectures)
|
|
*
|
|
* Note that, here we are using same standard kernel parameter "clocksource=",
|
|
* and not introducing any OMAP specific interface.
|
|
*/
|
|
static int __init omap2_override_clocksource(char *str)
|
|
{
|
|
if (!str)
|
|
return 0;
|
|
/*
|
|
* For OMAP architecture, we only have two options
|
|
* - sync_32k (default)
|
|
* - gp_timer (sys_clk based)
|
|
*/
|
|
if (!strcmp(str, "gp_timer"))
|
|
use_gptimer_clksrc = true;
|
|
|
|
return 0;
|
|
}
|
|
early_param("clocksource", omap2_override_clocksource);
|