/*
* linux/arch/arm/mach-omap1/clock.c
*
* Copyright (C) 2004 - 2005 Nokia corporation
* Written by Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com>
*
* Modified to use omap shared clock framework by
* Tony Lindgren <tony@atomide.com>
*
* 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.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <asm/io.h>
#include <asm/arch/usb.h>
#include <asm/arch/clock.h>
#include <asm/arch/sram.h>
#include "clock.h"
__u32 arm_idlect1_mask;
/*-------------------------------------------------------------------------
* Omap1 specific clock functions
*-------------------------------------------------------------------------*/
static void omap1_watchdog_recalc(struct clk * clk)
{
clk->rate = clk->parent->rate / 14;
}
static void omap1_uart_recalc(struct clk * clk)
{
unsigned int val = omap_readl(clk->enable_reg);
if (val & clk->enable_bit)
clk->rate = 48000000;
else
clk->rate = 12000000;
}
static int omap1_clk_enable_dsp_domain(struct clk *clk)
{
int retval;
retval = omap1_clk_enable(&api_ck.clk);
if (!retval) {
retval = omap1_clk_enable_generic(clk);
omap1_clk_disable(&api_ck.clk);
}
return retval;
}
static void omap1_clk_disable_dsp_domain(struct clk *clk)
{
if (omap1_clk_enable(&api_ck.clk) == 0) {
omap1_clk_disable_generic(clk);
omap1_clk_disable(&api_ck.clk);
}
}
static int omap1_clk_enable_uart_functional(struct clk *clk)
{
int ret;
struct uart_clk *uclk;
ret = omap1_clk_enable_generic(clk);
if (ret == 0) {
/* Set smart idle acknowledgement mode */
uclk = (struct uart_clk *)clk;
omap_writeb((omap_readb(uclk->sysc_addr) & ~0x10) | 8,
uclk->sysc_addr);
}
return ret;
}
static void omap1_clk_disable_uart_functional(struct clk *clk)
{
struct uart_clk *uclk;
/* Set force idle acknowledgement mode */
uclk = (struct uart_clk *)clk;
omap_writeb((omap_readb(uclk->sysc_addr) & ~0x18), uclk->sysc_addr);
omap1_clk_disable_generic(clk);
}
static void omap1_clk_allow_idle(struct clk *clk)
{
struct arm_idlect1_clk * iclk = (struct arm_idlect1_clk *)clk;
if (!(clk->flags & CLOCK_IDLE_CONTROL))
return;
if (iclk->no_idle_count > 0 && !(--iclk->no_idle_count))
arm_idlect1_mask |= 1 << iclk->idlect_shift;
}
static void omap1_clk_deny_idle(struct clk *clk)
{
struct arm_idlect1_clk * iclk = (struct arm_idlect1_clk *)clk;
if (!(clk->flags & CLOCK_IDLE_CONTROL))
return;
if (iclk->no_idle_count++ == 0)
arm_idlect1_mask &= ~(1 << iclk->idlect_shift);
}
static __u16 verify_ckctl_value(__u16 newval)
{
/* This function checks for following limitations set
* by the hardware (all conditions must be true):
* DSPMMU_CK == DSP_CK or DSPMMU_CK == DSP_CK/2
* ARM_CK >= TC_CK
* DSP_CK >= TC_CK
* DSPMMU_CK >= TC_CK
*
* In addition following rules are enforced:
* LCD_CK <= TC_CK
* ARMPER_CK <= TC_CK
*
* However, maximum frequencies are not checked for!
*/
__u8 per_exp;
__u8 lcd_exp;
__u8 arm_exp;
__u8 dsp_exp;
__u8 tc_exp;
__u8 dspmmu_exp;
per_exp = (newval >> CKCTL_PERDIV_OFFSET) & 3;
lcd_exp = (newval >> CKCTL_LCDDIV_OFFSET) & 3;
arm_exp = (newval >> CKCTL_ARMDIV_OFFSET) & 3;
dsp_exp = (newval >> CKCTL_DSPDIV_OFFSET) & 3;
tc_exp = (newval >> CKCTL_TCDIV_OFFSET) & 3;
dspmmu_exp = (newval >> CKCTL_DSPMMUDIV_OFFSET) & 3;
if (dspmmu_exp < dsp_exp)
dspmmu_exp = dsp_exp;
if (dspmmu_exp > dsp_exp+1)
dspmmu_exp = dsp_exp+1;
if (tc_exp < arm_exp)
tc_exp = arm_exp;
if (tc_exp < dspmmu_exp)
tc_exp = dspmmu_exp;
if (tc_exp > lcd_exp)
lcd_exp = tc_exp;
if (tc_exp > per_exp)
per_exp = tc_exp;
newval &= 0xf000;
newval |= per_exp << CKCTL_PERDIV_OFFSET;
newval |= lcd_exp << CKCTL_LCDDIV_OFFSET;
newval |= arm_exp << CKCTL_ARMDIV_OFFSET;
newval |= dsp_exp << CKCTL_DSPDIV_OFFSET;
newval |= tc_exp << CKCTL_TCDIV_OFFSET;
newval |= dspmmu_exp << CKCTL_DSPMMUDIV_OFFSET;
return newval;
}
static int calc_dsor_exp(struct clk *clk, unsigned long rate)
{
/* Note: If target frequency is too low, this function will return 4,
* which is invalid value. Caller must check for this value and act
* accordingly.
*
* Note: This function does not check for following limitations set
* by the hardware (all conditions must be true):
* DSPMMU_CK == DSP_CK or DSPMMU_CK == DSP_CK/2
* ARM_CK >= TC_CK
* DSP_CK >= TC_CK
* DSPMMU_CK >= TC_CK
*/
unsigned long realrate;
struct clk * parent;
unsigned dsor_exp;
if (unlikely(!(clk->flags & RATE_CKCTL)))
return -EINVAL;
parent = clk->parent;
if (unlikely(parent == 0))
return -EIO;
realrate = parent->rate;
for (dsor_exp=0; dsor_exp<4; dsor_exp++) {
if (realrate <= rate)
break;
realrate /= 2;
}
return dsor_exp;
}
static void omap1_ckctl_recalc(struct clk * clk)
{
int dsor;
/* Calculate divisor encoded as 2-bit exponent */
dsor = 1 << (3 & (omap_readw(ARM_CKCTL) >> clk->rate_offset));
if (unlikely(clk->rate == clk->parent->rate / dsor))
return; /* No change, quick exit */
clk->rate = clk->parent->rate / dsor;
if (unlikely(clk->flags & RATE_PROPAGATES))
propagate_rate(clk);
}
static void omap1_ckctl_recalc_dsp_domain(struct clk * clk)
{
int dsor;
/* Calculate divisor encoded as 2-bit exponent
*
* The clock control bits are in DSP domain,
* so api_ck is needed for access.
* Note that DSP_CKCTL virt addr = phys addr, so
* we must use __raw_readw() instead of omap_readw().
*/
omap1_clk_enable(&api_ck.clk);
dsor = 1 << (3 & (__raw_readw(DSP_CKCTL) >> clk->rate_offset));
omap1_clk_disable(&api_ck.clk);
if (unlikely(clk->rate == clk->parent->rate / dsor))
return; /* No change, quick exit */
clk->rate = clk->parent->rate / dsor;
if (unlikely(clk->flags & RATE_PROPAGATES))
propagate_rate(clk);
}
/* MPU virtual clock functions */
static int omap1_select_table_rate(struct clk * clk, unsigned long rate)
{
/* Find the highest supported frequency <= rate and switch to it */
struct mpu_rate * ptr;
if (clk != &virtual_ck_mpu)
return -EINVAL;
for (ptr = rate_table; ptr->rate; ptr++) {
if (ptr->xtal != ck_ref.rate)
continue;
/* DPLL1 cannot be reprogrammed without risking system crash */
if (likely(ck_dpll1.rate!=0) && ptr->pll_rate != ck_dpll1.rate)
continue;
/* Can check only after xtal frequency check */
if (ptr->rate <= rate)
break;
}
if (!ptr->rate)
return -EINVAL;
/*
* In most cases we should not need to reprogram DPLL.
* Reprogramming the DPLL is tricky, it must be done from SRAM.
*/
omap_sram_reprogram_clock(ptr->dpllctl_val, ptr->ckctl_val);
ck_dpll1.rate = ptr->pll_rate;
propagate_rate(&ck_dpll1);
return 0;
}
static int omap1_clk_set_rate_dsp_domain(struct clk *clk, unsigned long rate)
{
int ret = -EINVAL;
int dsor_exp;
__u16 regval;
if (clk->flags & RATE_CKCTL) {
dsor_exp = calc_dsor_exp(clk, rate);
if (dsor_exp > 3)
dsor_exp = -EINVAL;
if (dsor_exp < 0)
return dsor_exp;
regval = __raw_readw(DSP_CKCTL);
regval &= ~(3 << clk->rate_offset);
regval |= dsor_exp << clk->rate_offset;
__raw_writew(regval, DSP_CKCTL);
clk->rate = clk->parent->rate / (1 << dsor_exp);
ret = 0;
}
if (unlikely(ret == 0 && (clk->flags & RATE_PROPAGATES)))
propagate_rate(clk);
return ret;
}
static long omap1_round_to_table_rate(struct clk * clk, unsigned long rate)
{
/* Find the highest supported frequency <= rate */
struct mpu_rate * ptr;
long highest_rate;
if (clk != &virtual_ck_mpu)
return -EINVAL;
highest_rate = -EINVAL;
for (ptr = rate_table; ptr->rate; ptr++) {
if (ptr->xtal != ck_ref.rate)
continue;
highest_rate = ptr->rate;
/* Can check only after xtal frequency check */
if (ptr->rate <= rate)
break;
}
return highest_rate;
}
static unsigned calc_ext_dsor(unsigned long rate)
{
unsigned dsor;
/* MCLK and BCLK divisor selection is not linear:
* freq = 96MHz / dsor
*
* RATIO_SEL range: dsor <-> RATIO_SEL
* 0..6: (RATIO_SEL+2) <-> (dsor-2)
* 6..48: (8+(RATIO_SEL-6)*2) <-> ((dsor-8)/2+6)
* Minimum dsor is 2 and maximum is 96. Odd divisors starting from 9
* can not be used.
*/
for (dsor = 2; dsor < 96; ++dsor) {
if ((dsor & 1) && dsor > 8)
continue;
if (rate >= 96000000 / dsor)
break;
}
return dsor;
}
/* Only needed on 1510 */
static int omap1_set_uart_rate(struct clk * clk, unsigned long rate)
{
unsigned int val;
val = omap_readl(clk->enable_reg);
if (rate == 12000000)
val &= ~(1 << clk->enable_bit);
else if (rate == 48000000)
val |= (1 << clk->enable_bit);
else
return -EINVAL;
omap_writel(val, clk->enable_reg);
clk->rate = rate;
return 0;
}
/* External clock (MCLK & BCLK) functions */
static int omap1_set_ext_clk_rate(struct clk * clk, unsigned long rate)
{
unsigned dsor;
__u16 ratio_bits;
dsor = calc_ext_dsor(rate);
clk->rate = 96000000 / dsor;
if (dsor > 8)
ratio_bits = ((dsor - 8) / 2 + 6) << 2;
else
ratio_bits = (dsor - 2) << 2;
ratio_bits |= omap_readw(clk->enable_reg) & ~0xfd;
omap_writew(ratio_bits, clk->enable_reg);
return 0;
}
static long omap1_round_ext_clk_rate(struct clk * clk, unsigned long rate)
{
return 96000000 / calc_ext_dsor(rate);
}
static void omap1_init_ext_clk(struct clk * clk)
{
unsigned dsor;
__u16 ratio_bits;
/* Determine current rate and ensure clock is based on 96MHz APLL */
ratio_bits = omap_readw(clk->enable_reg) & ~1;
omap_writew(ratio_bits, clk->enable_reg);
ratio_bits = (ratio_bits & 0xfc) >> 2;
if (ratio_bits > 6)
dsor = (ratio_bits - 6) * 2 + 8;
else
dsor = ratio_bits + 2;
clk-> rate = 96000000 / dsor;
}
static int omap1_clk_enable(struct clk *clk)
{
int ret = 0;
if (clk->usecount++ == 0) {
if (likely(clk->parent)) {
ret = omap1_clk_enable(clk->parent);
if (unlikely(ret != 0)) {
clk->usecount--;
return ret;
}
if (clk->flags & CLOCK_NO_IDLE_PARENT)
if (!cpu_is_omap24xx())
omap1_clk_deny_idle(clk->parent);
}
ret = clk->enable(clk);
if (unlikely(ret != 0) && clk->parent) {
omap1_clk_disable(clk->parent);
clk->usecount--;
}
}
return ret;
}
static void omap1_clk_disable(struct clk *clk)
{
if (clk->usecount > 0 && !(--clk->usecount)) {
clk->disable(clk);
if (likely(clk->parent)) {
omap1_clk_disable(clk->parent);
if (clk->flags & CLOCK_NO_IDLE_PARENT)
if (!cpu_is_omap24xx())
omap1_clk_allow_idle(clk->parent);
}
}
}
static int omap1_clk_enable_generic(struct clk *clk)
{
__u16 regval16;
__u32 regval32;
if (clk->flags & ALWAYS_ENABLED)
return 0;
if (unlikely(clk->enable_reg == 0)) {
printk(KERN_ERR "clock.c: Enable for %s without enable code\n",
clk->name);
return 0;
}
if (clk->flags & ENABLE_REG_32BIT) {
if (clk->flags & VIRTUAL_IO_ADDRESS) {
regval32 = __raw_readl(clk->enable_reg);
regval32 |= (1 << clk->enable_bit);
__raw_writel(regval32, clk->enable_reg);
} else {
regval32 = omap_readl(clk->enable_reg);
regval32 |= (1 << clk->enable_bit);
omap_writel(regval32, clk->enable_reg);
}
} else {
if (clk->flags & VIRTUAL_IO_ADDRESS) {
regval16 = __raw_readw(clk->enable_reg);
regval16 |= (1 << clk->enable_bit);
__raw_writew(regval16, clk->enable_reg);
} else {
regval16 = omap_readw(clk->enable_reg);
regval16 |= (1 << clk->enable_bit);
omap_writew(regval16, clk->enable_reg);
}
}
return 0;
}
static void omap1_clk_disable_generic(struct clk *clk)
{
__u16 regval16;
__u32 regval32;
if (clk->enable_reg == 0)
return;
if (clk->flags & ENABLE_REG_32BIT) {
if (clk->flags & VIRTUAL_IO_ADDRESS) {
regval32 = __raw_readl(clk->enable_reg);
regval32 &= ~(1 << clk->enable_bit);
__raw_writel(regval32, clk->enable_reg);
} else {
regval32 = omap_readl(clk->enable_reg);
regval32 &= ~(1 << clk->enable_bit);
omap_writel(regval32, clk->enable_reg);
}
} else {
if (clk->flags & VIRTUAL_IO_ADDRESS) {
regval16 = __raw_readw(clk->enable_reg);
regval16 &= ~(1 << clk->enable_bit);
__raw_writew(regval16, clk->enable_reg);
} else {
regval16 = omap_readw(clk->enable_reg);
regval16 &= ~(1 << clk->enable_bit);
omap_writew(regval16, clk->enable_reg);
}
}
}
static long omap1_clk_round_rate(struct clk *clk, unsigned long rate)
{
int dsor_exp;
if (clk->flags & RATE_FIXED)
return clk->rate;
if (clk->flags & RATE_CKCTL) {
dsor_exp = calc_dsor_exp(clk, rate);
if (dsor_exp < 0)
return dsor_exp;
if (dsor_exp > 3)
dsor_exp = 3;
return clk->parent->rate / (1 << dsor_exp);
}
if(clk->round_rate != 0)
return clk->round_rate(clk, rate);
return clk->rate;
}
static int omap1_clk_set_rate(struct clk *clk, unsigned long rate)
{
int ret = -EINVAL;
int dsor_exp;
__u16 regval;
if (clk->set_rate)
ret = clk->set_rate(clk, rate);
else if (clk->flags & RATE_CKCTL) {
dsor_exp = calc_dsor_exp(clk, rate);
if (dsor_exp > 3)
dsor_exp = -EINVAL;
if (dsor_exp < 0)
return dsor_exp;
regval = omap_readw(ARM_CKCTL);
regval &= ~(3 << clk->rate_offset);
regval |= dsor_exp << clk->rate_offset;
regval = verify_ckctl_value(regval);
omap_writew(regval, ARM_CKCTL);
clk->rate = clk->parent->rate / (1 << dsor_exp);
ret = 0;
}
if (unlikely(ret == 0 && (clk->flags & RATE_PROPAGATES)))
propagate_rate(clk);
return ret;
}
/*-------------------------------------------------------------------------
* Omap1 clock reset and init functions
*-------------------------------------------------------------------------*/
#ifdef CONFIG_OMAP_RESET_CLOCKS
/*
* Resets some clocks that may be left on from bootloader,
* but leaves serial clocks on. See also omap_late_clk_reset().
*/
static inline void omap1_early_clk_reset(void)
{
//omap_writel(0x3 << 29, MOD_CONF_CTRL_0);
}
static int __init omap1_late_clk_reset(void)
{
/* Turn off all unused clocks */
struct clk *p;
__u32 regval32;
/* USB_REQ_EN will be disabled later if necessary (usb_dc_ck) */
regval32 = omap_readw(SOFT_REQ_REG) & (1 << 4);
omap_writew(regval32, SOFT_REQ_REG);
omap_writew(0, SOFT_REQ_REG2);
list_for_each_entry(p, &clocks, node) {
if (p->usecount > 0 || (p->flags & ALWAYS_ENABLED) ||
p->enable_reg == 0)
continue;
/* Clocks in the DSP domain need api_ck. Just assume bootloader
* has not enabled any DSP clocks */
if ((u32)p->enable_reg == DSP_IDLECT2) {
printk(KERN_INFO "Skipping reset check for DSP domain "
"clock \"%s\"\n", p->name);
continue;
}
/* Is the clock already disabled? */
if (p->flags & ENABLE_REG_32BIT) {
if (p->flags & VIRTUAL_IO_ADDRESS)
regval32 = __raw_readl(p->enable_reg);
else
regval32 = omap_readl(p->enable_reg);
} else {
if (p->flags & VIRTUAL_IO_ADDRESS)
regval32 = __raw_readw(p->enable_reg);
else
regval32 = omap_readw(p->enable_reg);
}
if ((regval32 & (1 << p->enable_bit)) == 0)
continue;
/* FIXME: This clock seems to be necessary but no-one
* has asked for its activation. */
if (p == &tc2_ck // FIX: pm.c (SRAM), CCP, Camera
|| p == &ck_dpll1out.clk // FIX: SoSSI, SSR
|| p == &arm_gpio_ck // FIX: GPIO code for 1510
) {
printk(KERN_INFO "FIXME: Clock \"%s\" seems unused\n",
p->name);
continue;
}
printk(KERN_INFO "Disabling unused clock \"%s\"... ", p->name);
p->disable(p);
printk(" done\n");
}
return 0;
}
late_initcall(omap1_late_clk_reset);
#else
#define omap1_early_clk_reset() {}
#endif
static struct clk_functions omap1_clk_functions = {
.clk_enable = omap1_clk_enable,
.clk_disable = omap1_clk_disable,
.clk_round_rate = omap1_clk_round_rate,
.clk_set_rate = omap1_clk_set_rate,
};
int __init omap1_clk_init(void)
{
struct clk ** clkp;
const struct omap_clock_config *info;
int crystal_type = 0; /* Default 12 MHz */
omap1_early_clk_reset();
clk_init(&omap1_clk_functions);
/* By default all idlect1 clocks are allowed to idle */
arm_idlect1_mask = ~0;
for (clkp = onchip_clks; clkp < onchip_clks+ARRAY_SIZE(onchip_clks); clkp++) {
if (((*clkp)->flags &CLOCK_IN_OMAP1510) && cpu_is_omap1510()) {
clk_register(*clkp);
continue;
}
if (((*clkp)->flags &CLOCK_IN_OMAP16XX) && cpu_is_omap16xx()) {
clk_register(*clkp);
continue;
}
if (((*clkp)->flags &CLOCK_IN_OMAP730) && cpu_is_omap730()) {
clk_register(*clkp);
continue;
}
if (((*clkp)->flags &CLOCK_IN_OMAP310) && cpu_is_omap310()) {
clk_register(*clkp);
continue;
}
}
info = omap_get_config(OMAP_TAG_CLOCK, struct omap_clock_config);
if (info != NULL) {
if (!cpu_is_omap1510())
crystal_type = info->system_clock_type;
}
#if defined(CONFIG_ARCH_OMAP730)
ck_ref.rate = 13000000;
#elif defined(CONFIG_ARCH_OMAP16XX)
if (crystal_type == 2)
ck_ref.rate = 19200000;
#endif
printk("Clocks: ARM_SYSST: 0x%04x DPLL_CTL: 0x%04x ARM_CKCTL: 0x%04x\n",
omap_readw(ARM_SYSST), omap_readw(DPLL_CTL),
omap_readw(ARM_CKCTL));
/* We want to be in syncronous scalable mode */
omap_writew(0x1000, ARM_SYSST);
#ifdef CONFIG_OMAP_CLOCKS_SET_BY_BOOTLOADER
/* Use values set by bootloader. Determine PLL rate and recalculate
* dependent clocks as if kernel had changed PLL or divisors.
*/
{
unsigned pll_ctl_val = omap_readw(DPLL_CTL);
ck_dpll1.rate = ck_ref.rate; /* Base xtal rate */
if (pll_ctl_val & 0x10) {
/* PLL enabled, apply multiplier and divisor */
if (pll_ctl_val & 0xf80)
ck_dpll1.rate *= (pll_ctl_val & 0xf80) >> 7;
ck_dpll1.rate /= ((pll_ctl_val & 0x60) >> 5) + 1;
} else {
/* PLL disabled, apply bypass divisor */
switch (pll_ctl_val & 0xc) {
case 0:
break;
case 0x4:
ck_dpll1.rate /= 2;
break;
default:
ck_dpll1.rate /= 4;
break;
}
}
}
propagate_rate(&ck_dpll1);
#else
/* Find the highest supported frequency and enable it */
if (omap1_select_table_rate(&virtual_ck_mpu, ~0)) {
printk(KERN_ERR "System frequencies not set. Check your config.\n");
/* Guess sane values (60MHz) */
omap_writew(0x2290, DPLL_CTL);
omap_writew(0x1005, ARM_CKCTL);
ck_dpll1.rate = 60000000;
propagate_rate(&ck_dpll1);
}
#endif
/* Cache rates for clocks connected to ck_ref (not dpll1) */
propagate_rate(&ck_ref);
printk(KERN_INFO "Clocking rate (xtal/DPLL1/MPU): "
"%ld.%01ld/%ld.%01ld/%ld.%01ld MHz\n",
ck_ref.rate / 1000000, (ck_ref.rate / 100000) % 10,
ck_dpll1.rate / 1000000, (ck_dpll1.rate / 100000) % 10,
arm_ck.rate / 1000000, (arm_ck.rate / 100000) % 10);
#ifdef CONFIG_MACH_OMAP_PERSEUS2
/* Select slicer output as OMAP input clock */
omap_writew(omap_readw(OMAP730_PCC_UPLD_CTRL) & ~0x1, OMAP730_PCC_UPLD_CTRL);
#endif
/* Turn off DSP and ARM_TIMXO. Make sure ARM_INTHCK is not divided */
omap_writew(omap_readw(ARM_CKCTL) & 0x0fff, ARM_CKCTL);
/* Put DSP/MPUI into reset until needed */
omap_writew(0, ARM_RSTCT1);
omap_writew(1, ARM_RSTCT2);
omap_writew(0x400, ARM_IDLECT1);
/*
* According to OMAP5910 Erratum SYS_DMA_1, bit DMACK_REQ (bit 8)
* of the ARM_IDLECT2 register must be set to zero. The power-on
* default value of this bit is one.
*/
omap_writew(0x0000, ARM_IDLECT2); /* Turn LCD clock off also */
/*
* Only enable those clocks we will need, let the drivers
* enable other clocks as necessary
*/
clk_enable(&armper_ck.clk);
clk_enable(&armxor_ck.clk);
clk_enable(&armtim_ck.clk); /* This should be done by timer code */
if (cpu_is_omap15xx())
clk_enable(&arm_gpio_ck);
return 0;
}