android_kernel_motorola_sm6225/arch/arm/mach-omap2/clock34xx.c
Roman Tereshonkov 3760d31f11 ARM: OMAP2: New DPLL clock framework
These changes is the result of the discussion with Paul Walmsley.
His ideas are included into this patch.

Remove DPLL output divider handling from DPLLs and CLKOUTX2 clocks,
and place it into specific DPLL output divider clocks (e.g., dpll3_m2_clk).
omap2_get_dpll_rate() now returns the correct DPLL rate, as represented
by the DPLL's CLKOUT output. Also add MPU and IVA2 subsystem clocks, along
with high-frequency bypass support.

Add support for DPLLs function in locked and bypass clock modes.

Signed-off-by: Roman Tereshonkov <roman.tereshonkov@nokia.com>
Acked-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2008-04-14 10:29:39 -07:00

235 lines
5.5 KiB
C

/*
* 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