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linux/arch/arm/mach-omap2/clock2xxx.c
Paul Walmsley 87a1b26c2d OMAP2xxx clock: move osc_clk code into mach-omap2/clkt2xxx_osc.c
Move the osc_clk clock functions from clock2xxx.c to
mach-omap2/clkt2xxx_osc.  This is intended to make the clock code
easier to understand, since all of the functions needed to manage the
osc_clk are now located in their own file, rather than being mixed
with other, unrelated functions.

Clock debugging is also now more finely-grained, since the DEBUG
macro can now be defined for osc_clk clocks alone.  This
should reduce unnecessary console noise when debugging.

Also, if at some future point the mach-omap2/ directory is split
into OMAP2/3/4 variants, this clkt file can be placed in the mach-omap2xxx/
directory, rather than shared with other chip types that don't use this
clock type.

Thanks to Alexander Shishkin <virtuoso@slind.org> for his comments to
improve the patch description.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Alexander Shishkin <virtuoso@slind.org>
2010-01-28 18:13:49 -07:00

159 lines
3.9 KiB
C

/*
* linux/arch/arm/mach-omap2/clock.c
*
* Copyright (C) 2005-2008 Texas Instruments, Inc.
* Copyright (C) 2004-2008 Nokia Corporation
*
* Contacts:
* Richard Woodruff <r-woodruff2@ti.com>
* Paul Walmsley
*
* Based on earlier work by Tuukka Tikkanen, Tony Lindgren,
* Gordon McNutt and RidgeRun, Inc.
*
* 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.
*/
#undef DEBUG
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/list.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/cpufreq.h>
#include <linux/bitops.h>
#include <plat/clock.h>
#include <plat/sram.h>
#include <plat/prcm.h>
#include <plat/clkdev_omap.h>
#include <asm/div64.h>
#include <asm/clkdev.h>
#include <plat/sdrc.h>
#include "clock.h"
#include "clock2xxx.h"
#include "opp2xxx.h"
#include "prm.h"
#include "prm-regbits-24xx.h"
#include "cm.h"
#include "cm-regbits-24xx.h"
struct clk *vclk, *sclk, *dclk;
void __iomem *prcm_clksrc_ctrl;
/*-------------------------------------------------------------------------
* Omap24xx specific clock functions
*-------------------------------------------------------------------------*/
/**
* omap2430_clk_i2chs_find_idlest - return CM_IDLEST info for 2430 I2CHS
* @clk: struct clk * being enabled
* @idlest_reg: void __iomem ** to store CM_IDLEST reg address into
* @idlest_bit: pointer to a u8 to store the CM_IDLEST bit shift into
*
* OMAP2430 I2CHS CM_IDLEST bits are in CM_IDLEST1_CORE, but the
* CM_*CLKEN bits are in CM_{I,F}CLKEN2_CORE. This custom function
* passes back the correct CM_IDLEST register address for I2CHS
* modules. No return value.
*/
static void omap2430_clk_i2chs_find_idlest(struct clk *clk,
void __iomem **idlest_reg,
u8 *idlest_bit)
{
*idlest_reg = OMAP_CM_REGADDR(CORE_MOD, CM_IDLEST);
*idlest_bit = clk->enable_bit;
}
/* 2430 I2CHS has non-standard IDLEST register */
const struct clkops clkops_omap2430_i2chs_wait = {
.enable = omap2_dflt_clk_enable,
.disable = omap2_dflt_clk_disable,
.find_idlest = omap2430_clk_i2chs_find_idlest,
.find_companion = omap2_clk_dflt_find_companion,
};
#ifdef OLD_CK
/* Recalculate SYST_CLK */
static void omap2_sys_clk_recalc(struct clk *clk)
{
u32 div = PRCM_CLKSRC_CTRL;
div &= (1 << 7) | (1 << 6); /* Test if ext clk divided by 1 or 2 */
div >>= clk->rate_offset;
clk->rate = (clk->parent->rate / div);
propagate_rate(clk);
}
#endif /* OLD_CK */
u32 omap2xxx_get_sysclkdiv(void)
{
u32 div;
div = __raw_readl(prcm_clksrc_ctrl);
div &= OMAP_SYSCLKDIV_MASK;
div >>= OMAP_SYSCLKDIV_SHIFT;
return div;
}
unsigned long omap2_sys_clk_recalc(struct clk *clk)
{
return clk->parent->rate / omap2xxx_get_sysclkdiv();
}
/*
* Set clocks for bypass mode for reboot to work.
*/
void omap2_clk_prepare_for_reboot(void)
{
u32 rate;
if (vclk == NULL || sclk == NULL)
return;
rate = clk_get_rate(sclk);
clk_set_rate(vclk, rate);
}
/*
* Switch the MPU rate if specified on cmdline.
* We cannot do this early until cmdline is parsed.
*/
static int __init omap2_clk_arch_init(void)
{
struct clk *virt_prcm_set, *sys_ck, *dpll_ck, *mpu_ck;
unsigned long sys_ck_rate;
if (!mpurate)
return -EINVAL;
virt_prcm_set = clk_get(NULL, "virt_prcm_set");
sys_ck = clk_get(NULL, "sys_ck");
dpll_ck = clk_get(NULL, "dpll_ck");
mpu_ck = clk_get(NULL, "mpu_ck");
if (clk_set_rate(virt_prcm_set, mpurate))
printk(KERN_ERR "Could not find matching MPU rate\n");
recalculate_root_clocks();
sys_ck_rate = clk_get_rate(sys_ck);
pr_info("Switched to new clocking rate (Crystal/DPLL/MPU): "
"%ld.%01ld/%ld/%ld MHz\n",
(sys_ck_rate / 1000000), (sys_ck_rate / 100000) % 10,
(clk_get_rate(dpll_ck) / 1000000),
(clk_get_rate(mpu_ck) / 1000000));
return 0;
}
arch_initcall(omap2_clk_arch_init);