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linux/arch/arm/mach-omap2/timer.c

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/*
* linux/arch/arm/mach-omap2/timer.c
*
* OMAP2 GP timer support.
*
* Copyright (C) 2009 Nokia Corporation
*
* Update to use new clocksource/clockevent layers
* Author: Kevin Hilman, MontaVista Software, Inc. <source@mvista.com>
* Copyright (C) 2007 MontaVista Software, Inc.
*
* Original driver:
* Copyright (C) 2005 Nokia Corporation
* Author: Paul Mundt <paul.mundt@nokia.com>
* Juha Yrjölä <juha.yrjola@nokia.com>
* OMAP Dual-mode timer framework support by Timo Teras
*
* Some parts based off of TI's 24xx code:
*
* Copyright (C) 2004-2009 Texas Instruments, Inc.
*
* Roughly modelled after the OMAP1 MPU timer code.
* Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/clk.h>
#include <linux/clocksource.h>
ARM: OMAP: Split plat/hardware.h, use local soc.h for omap2+ As the plat and mach includes need to disappear for single zImage work, we need to remove plat/hardware.h. Do this by splitting plat/hardware.h into omap1 and omap2+ specific files. The old plat/hardware.h already has omap1 only defines, so it gets moved to mach/hardware.h for omap1. For omap2+, we use the local soc.h that for now just includes the related SoC headers to keep this patch more readable. Note that the local soc.h still includes plat/cpu.h that can be dealt with in later patches. Let's also include plat/serial.h from common.h for all the board-*.c files. This allows making the include files local later on without patching these files again. Note that only minimal changes are done in this patch for the drivers/watchdog/omap_wdt.c driver to keep things compiling. Further patches are needed to eventually remove cpu_is_omap usage in the drivers. Also only minimal changes are done to sound/soc/omap/* to remove the unneeded includes and to define OMAP44XX_MCPDM_L3_BASE locally so there's no need to include omap44xx.h. While at it, also sort some of the includes in the standard way. Cc: linux-watchdog@vger.kernel.org Cc: alsa-devel@alsa-project.org Cc: Peter Ujfalusi <peter.ujfalusi@ti.com> Cc: Jarkko Nikula <jarkko.nikula@bitmer.com> Cc: Liam Girdwood <lrg@ti.com> Acked-by: Wim Van Sebroeck <wim@iguana.be> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-08-31 10:59:07 -07:00
#include "soc.h"
#include "common.h"
#include "control.h"
#include "omap-secure.h"
#define REALTIME_COUNTER_BASE 0x48243200
#define INCREMENTER_NUMERATOR_OFFSET 0x10
#define INCREMENTER_DENUMERATOR_RELOAD_OFFSET 0x14
#define NUMERATOR_DENUMERATOR_MASK 0xfffff000
static unsigned long arch_timer_freq;
void set_cntfreq(void)
{
omap_smc1(OMAP5_DRA7_MON_SET_CNTFRQ_INDEX, arch_timer_freq);
}
/*
* The realtime counter also called master counter, is a free-running
* counter, which is related to real time. It produces the count used
* by the CPU local timer peripherals in the MPU cluster. The timer counts
* at a rate of 6.144 MHz. Because the device operates on different clocks
* in different power modes, the master counter shifts operation between
* clocks, adjusting the increment per clock in hardware accordingly to
* maintain a constant count rate.
*/
static void __init realtime_counter_init(void)
{
void __iomem *base;
static struct clk *sys_clk;
unsigned long rate;
unsigned int reg;
unsigned long long num, den;
base = ioremap(REALTIME_COUNTER_BASE, SZ_32);
if (!base) {
pr_err("%s: ioremap failed\n", __func__);
return;
}
sys_clk = clk_get(NULL, "sys_clkin");
if (IS_ERR(sys_clk)) {
pr_err("%s: failed to get system clock handle\n", __func__);
iounmap(base);
return;
}
rate = clk_get_rate(sys_clk);
clk_put(sys_clk);
if (soc_is_dra7xx()) {
/*
* Errata i856 says the 32.768KHz crystal does not start at
* power on, so the CPU falls back to an emulated 32KHz clock
* based on sysclk / 610 instead. This causes the master counter
* frequency to not be 6.144MHz but at sysclk / 610 * 375 / 2
* (OR sysclk * 75 / 244)
*
* This affects at least the DRA7/AM572x 1.0, 1.1 revisions.
* Of course any board built without a populated 32.768KHz
* crystal would also need this fix even if the CPU is fixed
* later.
*
* Either case can be detected by using the two speedselect bits
* If they are not 0, then the 32.768KHz clock driving the
* coarse counter that corrects the fine counter every time it
* ticks is actually rate/610 rather than 32.768KHz and we
* should compensate to avoid the 570ppm (at 20MHz, much worse
* at other rates) too fast system time.
*/
reg = omap_ctrl_readl(DRA7_CTRL_CORE_BOOTSTRAP);
if (reg & DRA7_SPEEDSELECT_MASK) {
num = 75;
den = 244;
goto sysclk1_based;
}
}
/* Numerator/denumerator values refer TRM Realtime Counter section */
switch (rate) {
case 12000000:
num = 64;
den = 125;
break;
case 13000000:
num = 768;
den = 1625;
break;
case 19200000:
num = 8;
den = 25;
break;
case 20000000:
num = 192;
den = 625;
break;
case 26000000:
num = 384;
den = 1625;
break;
case 27000000:
num = 256;
den = 1125;
break;
case 38400000:
default:
/* Program it for 38.4 MHz */
num = 4;
den = 25;
break;
}
sysclk1_based:
/* Program numerator and denumerator registers */
reg = readl_relaxed(base + INCREMENTER_NUMERATOR_OFFSET) &
NUMERATOR_DENUMERATOR_MASK;
reg |= num;
writel_relaxed(reg, base + INCREMENTER_NUMERATOR_OFFSET);
reg = readl_relaxed(base + INCREMENTER_DENUMERATOR_RELOAD_OFFSET) &
NUMERATOR_DENUMERATOR_MASK;
reg |= den;
writel_relaxed(reg, base + INCREMENTER_DENUMERATOR_RELOAD_OFFSET);
arch_timer_freq = DIV_ROUND_UP_ULL(rate * num, den);
set_cntfreq();
iounmap(base);
ARM: OMAP2+: timer: remove CONFIG_OMAP_32K_TIMER CONFIG_OMAP_32K_TIMER is kind of standing on the single zImage way. Make OMAP2+ timer code independant from the CONFIG_OMAP_32K_TIMER setting. To remove the dependancy, several conversions/additions had to be done: 1) Timer initialization functions are named by the platform name and the clock source in use. This also makes it possible to define and use the GPTIMER as the clock source instead of the 32K timer on platforms that do not have the 32K timer ip block or the 32K timer is not wired on the board. Currently, the the timer is chosen in the machine_desc structure on per board basis. Later, DT should be used to choose the timer. 2) Settings under the CONFIG_OMAP_32K_TIMER option are used as defaults and those under !CONFIG_OMAP_32K_TIMER are removed. This removes the CONFIG_OMAP_32K_TIMER on OMAP2+ timer code. 3) Since we have all the timers defined inside machine_desc structure and we no longer need the fallback to gp_timer clock source in case 32k_timer clock source is unavailable (namely on AM33xx), we no longer need the #ifdef around omap2_sync32k_clocksource_init() function. Remove the #ifdef CONFIG_OMAP_32K_TIMER around the omap2_sync32k_clocksource_init() function. Signed-off-by: Igor Grinberg <grinberg@compulab.co.il> Cc: Jon Hunter <jon-hunter@ti.com> Cc: Santosh Shilimkar <santosh.shilimkar@ti.com> Cc: Vaibhav Hiremath <hvaibhav@ti.com> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Reviewed-by: Jon Hunter <jon-hunter@ti.com>
2012-11-20 00:17:15 -07:00
}
void __init omap5_realtime_timer_init(void)
{
omap_clk_init();
realtime_counter_init();
timer_probe();
}