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linux/arch/arm/mach-omap2/clock34xx.c

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/*
* OMAP3-specific clock framework functions
*
* Copyright (C) 2007 Texas Instruments, Inc.
* Copyright (C) 2007 Nokia Corporation
*
* Written by Paul Walmsley
*
* Parts of this code are based on code written by
* Richard Woodruff, Tony Lindgren, Tuukka Tikkanen, Karthik Dasu
*
* 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 <asm/arch/clock.h>
#include <asm/arch/sram.h>
#include <asm/div64.h>
#include <asm/bitops.h>
#include "memory.h"
#include "clock.h"
#include "clock34xx.h"
#include "prm.h"
#include "prm-regbits-34xx.h"
#include "cm.h"
#include "cm-regbits-34xx.h"
/* CM_CLKEN_PLL*.EN* bit values */
#define DPLL_LOCKED 0x7
/**
* omap3_dpll_recalc - recalculate DPLL rate
* @clk: DPLL struct clk
*
* Recalculate and propagate the DPLL rate.
*/
static void omap3_dpll_recalc(struct clk *clk)
{
clk->rate = omap2_get_dpll_rate(clk);
propagate_rate(clk);
}
/**
* omap3_clkoutx2_recalc - recalculate DPLL X2 output virtual clock rate
* @clk: DPLL output struct clk
*
* Using parent clock DPLL data, look up DPLL state. If locked, set our
* rate to the dpll_clk * 2; otherwise, just use dpll_clk.
*/
static void omap3_clkoutx2_recalc(struct clk *clk)
{
const struct dpll_data *dd;
u32 v;
struct clk *pclk;
/* Walk up the parents of clk, looking for a DPLL */
pclk = clk->parent;
while (pclk && !pclk->dpll_data)
pclk = pclk->parent;
/* clk does not have a DPLL as a parent? */
WARN_ON(!pclk);
dd = pclk->dpll_data;
WARN_ON(!dd->control_reg || !dd->enable_mask);
v = __raw_readl(dd->control_reg) & dd->enable_mask;
v >>= __ffs(dd->enable_mask);
if (v != DPLL_LOCKED)
clk->rate = clk->parent->rate;
else
clk->rate = clk->parent->rate * 2;
if (clk->flags & RATE_PROPAGATES)
propagate_rate(clk);
}
/*
* As it is structured now, this will prevent an OMAP2/3 multiboot
* kernel from compiling. This will need further attention.
*/
#if defined(CONFIG_ARCH_OMAP3)
static struct clk_functions omap2_clk_functions = {
.clk_enable = omap2_clk_enable,
.clk_disable = omap2_clk_disable,
.clk_round_rate = omap2_clk_round_rate,
.clk_set_rate = omap2_clk_set_rate,
.clk_set_parent = omap2_clk_set_parent,
.clk_disable_unused = omap2_clk_disable_unused,
};
/*
* Set clocks for bypass mode for reboot to work.
*/
void omap2_clk_prepare_for_reboot(void)
{
/* REVISIT: Not ready for 343x */
#if 0
u32 rate;
if (vclk == NULL || sclk == NULL)
return;
rate = clk_get_rate(sclk);
clk_set_rate(vclk, rate);
#endif
}
/* REVISIT: Move this init stuff out into clock.c */
/*
* 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)
{
if (!mpurate)
return -EINVAL;
/* REVISIT: not yet ready for 343x */
#if 0
if (omap2_select_table_rate(&virt_prcm_set, mpurate))
printk(KERN_ERR "Could not find matching MPU rate\n");
#endif
recalculate_root_clocks();
printk(KERN_INFO "Switched to new clocking rate (Crystal/DPLL3/MPU): "
"%ld.%01ld/%ld/%ld MHz\n",
(osc_sys_ck.rate / 1000000), (osc_sys_ck.rate / 100000) % 10,
(core_ck.rate / 1000000), (dpll1_fck.rate / 1000000)) ;
return 0;
}
arch_initcall(omap2_clk_arch_init);
int __init omap2_clk_init(void)
{
/* struct prcm_config *prcm; */
struct clk **clkp;
/* u32 clkrate; */
u32 cpu_clkflg;
/* REVISIT: Ultimately this will be used for multiboot */
#if 0
if (cpu_is_omap242x()) {
cpu_mask = RATE_IN_242X;
cpu_clkflg = CLOCK_IN_OMAP242X;
clkp = onchip_24xx_clks;
} else if (cpu_is_omap2430()) {
cpu_mask = RATE_IN_243X;
cpu_clkflg = CLOCK_IN_OMAP243X;
clkp = onchip_24xx_clks;
}
#endif
if (cpu_is_omap34xx()) {
cpu_mask = RATE_IN_343X;
cpu_clkflg = CLOCK_IN_OMAP343X;
clkp = onchip_34xx_clks;
/*
* Update this if there are further clock changes between ES2
* and production parts
*/
if (is_sil_rev_equal_to(OMAP3430_REV_ES1_0)) {
/* No 3430ES1-only rates exist, so no RATE_IN_3430ES1 */
cpu_clkflg |= CLOCK_IN_OMAP3430ES1;
} else {
cpu_mask |= RATE_IN_3430ES2;
cpu_clkflg |= CLOCK_IN_OMAP3430ES2;
}
}
clk_init(&omap2_clk_functions);
for (clkp = onchip_34xx_clks;
clkp < onchip_34xx_clks + ARRAY_SIZE(onchip_34xx_clks);
clkp++) {
if ((*clkp)->flags & cpu_clkflg)
clk_register(*clkp);
}
/* REVISIT: Not yet ready for OMAP3 */
#if 0
/* Check the MPU rate set by bootloader */
clkrate = omap2_get_dpll_rate_24xx(&dpll_ck);
for (prcm = rate_table; prcm->mpu_speed; prcm++) {
if (!(prcm->flags & cpu_mask))
continue;
if (prcm->xtal_speed != sys_ck.rate)
continue;
if (prcm->dpll_speed <= clkrate)
break;
}
curr_prcm_set = prcm;
#endif
recalculate_root_clocks();
printk(KERN_INFO "Clocking rate (Crystal/DPLL/ARM core): "
"%ld.%01ld/%ld/%ld MHz\n",
(osc_sys_ck.rate / 1000000), (osc_sys_ck.rate / 100000) % 10,
(core_ck.rate / 1000000), (arm_fck.rate / 1000000));
/*
* Only enable those clocks we will need, let the drivers
* enable other clocks as necessary
*/
clk_enable_init_clocks();
/* Avoid sleeping during omap2_clk_prepare_for_reboot() */
/* REVISIT: not yet ready for 343x */
#if 0
vclk = clk_get(NULL, "virt_prcm_set");
sclk = clk_get(NULL, "sys_ck");
#endif
return 0;
}
#endif