/*
* Clock interface for OMAP
*
* Copyright (C) 2001 RidgeRun, Inc
* Written by Gordon McNutt <gmcnutt@ridgerun.com>
* Updated 2004 for Linux 2.6 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 as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
* NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/spinlock.h>
#include <asm/errno.h>
#include <asm/io.h>
#include <asm/arch/clocks.h>
#include <asm/arch/board.h>
/* Input clock in MHz */
static unsigned int source_clock = 12;
/*
* We use one spinlock for all clock registers for now. We may want to
* change this to be clock register specific later on. Before we can do
* that, we need to map out the shared clock registers.
*/
static spinlock_t clock_lock = SPIN_LOCK_UNLOCKED;
typedef struct {
char *name;
__u8 flags;
ck_t parent;
unsigned long rate_reg; /* Clock rate register */
unsigned long enbl_reg; /* Enable register */
unsigned long idle_reg; /* Idle register */
unsigned long slct_reg; /* Select register */
__s8 rate_shift; /* Clock rate bit shift */
__s8 enbl_shift; /* Clock enable bit shift */
__s8 idle_shift; /* Clock idle bit shift */
__s8 slct_shift; /* Clock select bit shift */
} ck_info_t;
#define CK_NAME(ck) ck_info_table[ck].name
#define CK_FLAGS(ck) ck_info_table[ck].flags
#define CK_PARENT(ck) ck_info_table[ck].parent
#define CK_RATE_REG(ck) ck_info_table[ck].rate_reg
#define CK_ENABLE_REG(ck) ck_info_table[ck].enbl_reg
#define CK_IDLE_REG(ck) ck_info_table[ck].idle_reg
#define CK_SELECT_REG(ck) ck_info_table[ck].slct_reg
#define CK_RATE_SHIFT(ck) ck_info_table[ck].rate_shift
#define CK_ENABLE_SHIFT(ck) ck_info_table[ck].enbl_shift
#define CK_IDLE_SHIFT(ck) ck_info_table[ck].idle_shift
#define CK_SELECT_SHIFT(ck) ck_info_table[ck].slct_shift
#define CK_CAN_CHANGE_RATE(cl) (CK_FLAGS(ck) & CK_RATEF)
#define CK_CAN_DISABLE(cl) (CK_FLAGS(ck) & CK_ENABLEF)
#define CK_CAN_IDLE(cl) (CK_FLAGS(ck) & CK_IDLEF)
#define CK_CAN_SWITCH(cl) (CK_FLAGS(ck) & CK_SELECTF)
static ck_info_t ck_info_table[] = {
{
.name = "clkin",
.flags = 0,
.parent = OMAP_CLKIN,
}, {
.name = "ck_gen1",
.flags = CK_RATEF | CK_IDLEF,
.rate_reg = CK_DPLL1,
.idle_reg = ARM_IDLECT1,
.idle_shift = IDLDPLL_ARM,
.parent = OMAP_CLKIN,
}, {
.name = "ck_gen2",
.flags = 0,
.parent = OMAP_CK_GEN1,
}, {
.name = "ck_gen3",
.flags = 0,
.parent = OMAP_CK_GEN1,
}, {
.name = "tc_ck",
.flags = CK_RATEF | CK_IDLEF,
.parent = OMAP_CK_GEN3,
.rate_reg = ARM_CKCTL, /* ARM_CKCTL[TCDIV(9:8)] */
.idle_reg = ARM_IDLECT1,
.rate_shift = TCDIV,
.idle_shift = IDLIF_ARM
}, {
.name = "arm_ck",
.flags = CK_IDLEF | CK_RATEF,
.parent = OMAP_CK_GEN1,
.rate_reg = ARM_CKCTL, /* ARM_CKCTL[ARMDIV(5:4)] */
.idle_reg = ARM_IDLECT1,
.rate_shift = ARMDIV,
.idle_shift = SETARM_IDLE,
}, {
.name = "mpuper_ck",
.flags = CK_RATEF | CK_IDLEF | CK_ENABLEF,
.parent = OMAP_CK_GEN1,
.rate_reg = ARM_CKCTL, /* ARM_CKCTL[PERDIV(1:0)] */
.enbl_reg = ARM_IDLECT2,
.idle_reg = ARM_IDLECT1,
.rate_shift = PERDIV,
.enbl_shift = EN_PERCK,
.idle_shift = IDLPER_ARM
}, {
.name = "arm_gpio_ck",
.flags = CK_ENABLEF,
.parent = OMAP_CK_GEN1,
.enbl_reg = ARM_IDLECT2,
.enbl_shift = EN_GPIOCK
}, {
.name = "mpuxor_ck",
.flags = CK_ENABLEF | CK_IDLEF,
.parent = OMAP_CLKIN,
.idle_reg = ARM_IDLECT1,
.enbl_reg = ARM_IDLECT2,
.idle_shift = IDLXORP_ARM,
.enbl_shift = EN_XORPCK
}, {
.name = "mputim_ck",
.flags = CK_IDLEF | CK_ENABLEF | CK_SELECTF,
.parent = OMAP_CLKIN,
.idle_reg = ARM_IDLECT1,
.enbl_reg = ARM_IDLECT2,
.slct_reg = ARM_CKCTL,
.idle_shift = IDLTIM_ARM,
.enbl_shift = EN_TIMCK,
.slct_shift = ARM_TIMXO
}, {
.name = "mpuwd_ck",
.flags = CK_IDLEF | CK_ENABLEF,
.parent = OMAP_CLKIN,
.idle_reg = ARM_IDLECT1,
.enbl_reg = ARM_IDLECT2,
.idle_shift = IDLWDT_ARM,
.enbl_shift = EN_WDTCK,
}, {
.name = "dsp_ck",
.flags = CK_RATEF | CK_ENABLEF,
.parent = OMAP_CK_GEN2,
.rate_reg = ARM_CKCTL, /* ARM_CKCTL[DSPDIV(7:6)] */
.enbl_reg = ARM_CKCTL,
.rate_shift = DSPDIV,
.enbl_shift = EN_DSPCK,
}, {
.name = "dspmmu_ck",
.flags = CK_RATEF | CK_ENABLEF,
.parent = OMAP_CK_GEN2,
.rate_reg = ARM_CKCTL, /* ARM_CKCTL[DSPMMUDIV(11:10)] */
.enbl_reg = ARM_CKCTL,
.rate_shift = DSPMMUDIV,
.enbl_shift = EN_DSPCK,
}, {
.name = "dma_ck",
.flags = CK_RATEF | CK_IDLEF | CK_ENABLEF,
.parent = OMAP_CK_GEN3,
.rate_reg = ARM_CKCTL, /* ARM_CKCTL[TCDIV(9:8)] */
.idle_reg = ARM_IDLECT1,
.enbl_reg = ARM_IDLECT2,
.rate_shift = TCDIV,
.idle_shift = IDLIF_ARM,
.enbl_shift = DMACK_REQ
}, {
.name = "api_ck",
.flags = CK_RATEF | CK_IDLEF | CK_ENABLEF,
.parent = OMAP_CK_GEN3,
.rate_reg = ARM_CKCTL, /* ARM_CKCTL[TCDIV(9:8)] */
.idle_reg = ARM_IDLECT1,
.enbl_reg = ARM_IDLECT2,
.rate_shift = TCDIV,
.idle_shift = IDLAPI_ARM,
.enbl_shift = EN_APICK,
}, {
.name = "hsab_ck",
.flags = CK_RATEF | CK_IDLEF | CK_ENABLEF,
.parent = OMAP_CK_GEN3,
.rate_reg = ARM_CKCTL, /* ARM_CKCTL[TCDIV(9:8)] */
.idle_reg = ARM_IDLECT1,
.enbl_reg = ARM_IDLECT2,
.rate_shift = TCDIV,
.idle_shift = IDLHSAB_ARM,
.enbl_shift = EN_HSABCK,
}, {
.name = "lbfree_ck",
.flags = CK_RATEF | CK_ENABLEF,
.parent = OMAP_CK_GEN3,
.rate_reg = ARM_CKCTL, /* ARM_CKCTL[TCDIV(9:8)] */
.enbl_reg = ARM_IDLECT2,
.rate_shift = TCDIV,
.enbl_shift = EN_LBFREECK,
}, {
.name = "lb_ck",
.flags = CK_RATEF | CK_IDLEF | CK_ENABLEF,
.parent = OMAP_CK_GEN3,
.rate_reg = ARM_CKCTL, /* ARM_CKCTL[TCDIV(9:8)] */
.idle_reg = ARM_IDLECT1,
.enbl_reg = ARM_IDLECT2,
.rate_shift = TCDIV,
.idle_shift = IDLLB_ARM,
.enbl_shift = EN_LBCK,
}, {
.name = "lcd_ck",
.flags = CK_RATEF | CK_IDLEF | CK_ENABLEF,
.parent = OMAP_CK_GEN3,
.rate_reg = ARM_CKCTL, /* ARM_CKCTL[LCDDIV(3:2)] */
.idle_reg = ARM_IDLECT1,
.enbl_reg = ARM_IDLECT2,
.rate_shift = LCDDIV,
.idle_shift = IDLLCD_ARM,
.enbl_shift = EN_LCDCK,
},
};
/*****************************************************************************/
#define CK_IN_RANGE(ck) (!((ck < OMAP_CK_MIN) || (ck > OMAP_CK_MAX)))
int ck_auto_unclock = 1;
int ck_debug = 0;
#define CK_MAX_PLL_FREQ OMAP_CK_MAX_RATE
static __u8 ck_valid_table[CK_MAX_PLL_FREQ / 8 + 1];
static __u8 ck_lookup_table[CK_MAX_PLL_FREQ];
int
ck_set_input(ck_t ck, ck_t input)
{
int ret = 0, shift;
unsigned short reg;
unsigned long flags;
if (!CK_IN_RANGE(ck) || !CK_CAN_SWITCH(ck)) {
ret = -EINVAL;
goto exit;
}
reg = omap_readw(CK_SELECT_REG(ck));
shift = CK_SELECT_SHIFT(ck);
spin_lock_irqsave(&clock_lock, flags);
if (input == OMAP_CLKIN) {
reg &= ~(1 << shift);
omap_writew(reg, CK_SELECT_REG(ck));
goto exit;
} else if (input == CK_PARENT(ck)) {
reg |= (1 << shift);
omap_writew(reg, CK_SELECT_REG(ck));
goto exit;
}
ret = -EINVAL;
exit:
spin_unlock_irqrestore(&clock_lock, flags);
return ret;
}
int
ck_get_input(ck_t ck, ck_t * input)
{
int ret = -EINVAL;
unsigned long flags;
if (!CK_IN_RANGE(ck))
goto exit;
ret = 0;
spin_lock_irqsave(&clock_lock, flags);
if (CK_CAN_SWITCH(ck)) {
int shift;
unsigned short reg;
reg = omap_readw(CK_SELECT_REG(ck));
shift = CK_SELECT_SHIFT(ck);
if (reg & (1 << shift)) {
*input = CK_PARENT(ck);
goto exit;
}
}
*input = OMAP_CLKIN;
exit:
spin_unlock_irqrestore(&clock_lock, flags);
return ret;
}
static int
__ck_set_pll_rate(ck_t ck, int rate)
{
unsigned short pll;
unsigned long flags;
if ((rate < 0) || (rate > CK_MAX_PLL_FREQ))
return -EINVAL;
/* Scan downward for the closest matching frequency */
while (rate && !test_bit(rate, (unsigned long *)&ck_valid_table))
rate--;
if (!rate) {
printk(KERN_ERR "%s: couldn't find a matching rate\n",
__FUNCTION__);
return -EINVAL;
}
spin_lock_irqsave(&clock_lock, flags);
pll = omap_readw(CK_RATE_REG(ck));
/* Clear the rate bits */
pll &= ~(0x1f << 5);
/* Set the rate bits */
pll |= (ck_lookup_table[rate - 1] << 5);
omap_writew(pll, CK_RATE_REG(ck));
spin_unlock_irqrestore(&clock_lock, flags);
return 0;
}
static int
__ck_set_clkm_rate(ck_t ck, int rate)
{
int shift, prate, div, ret;
unsigned short reg;
unsigned long flags;
spin_lock_irqsave(&clock_lock, flags);
/*
* We can only set this clock's value to a fraction of its
* parent's value. The interface says I'll round down when necessary.
* So first let's get the parent's current rate.
*/
prate = ck_get_rate(CK_PARENT(ck));
/*
* Let's just start with the highest fraction and keep searching
* down through available rates until we find one less than or equal
* to the desired rate.
*/
for (div = 0; div < 4; div++) {
if (prate <= rate)
break;
prate = prate / 2;
}
/*
* Oops. Looks like the caller wants a rate lower than we can support.
*/
if (div == 5) {
printk(KERN_ERR "%s: %d is too low\n",
__FUNCTION__, rate);
ret = -EINVAL;
goto exit;
}
/*
* One more detail: if this clock supports more than one parent, then
* we're going to automatically switch over to the parent which runs
* through the divisor. For omap this is not ambiguous because for all
* such clocks one choice is always OMAP_CLKIN (which doesn't run
* through the divisor) and the other is whatever I encoded as
* CK_PARENT. Note that I wait until we get this far because I don't
* want to switch the input until we're sure this is going to work.
*/
if (CK_CAN_SWITCH(ck))
if ((ret = ck_set_input(ck, CK_PARENT(ck))) < 0) {
BUG();
goto exit;
}
/*
* At last, we can set the divisor. Clear the old rate bits and
* set the new ones.
*/
reg = omap_readw(CK_RATE_REG(ck));
shift = CK_RATE_SHIFT(ck);
reg &= ~(3 << shift);
reg |= (div << shift);
omap_writew(reg, CK_RATE_REG(ck));
/* And return the new (actual, after rounding down) rate. */
ret = prate;
exit:
spin_unlock_irqrestore(&clock_lock, flags);
return ret;
}
int
ck_set_rate(ck_t ck, int rate)
{
int ret = -EINVAL;
if (!CK_IN_RANGE(ck) || !CK_CAN_CHANGE_RATE(ck))
goto exit;
switch (ck) {
default:
ret = __ck_set_clkm_rate(ck, rate);
break;
case OMAP_CK_GEN1:
ret = __ck_set_pll_rate(ck, rate);
break;
};
exit:
return ret;
}
static int
__ck_get_pll_rate(ck_t ck)
{
int m, d;
unsigned short pll = omap_readw(CK_RATE_REG(ck));
m = (pll & (0x1f << 7)) >> 7;
m = m ? m : 1;
d = (pll & (3 << 5)) >> 5;
d++;
return ((source_clock * m) / d);
}
static int
__ck_get_clkm_rate(ck_t ck)
{
static int bits2div[] = { 1, 2, 4, 8 };
int in, bits, reg, shift;
reg = omap_readw(CK_RATE_REG(ck));
shift = CK_RATE_SHIFT(ck);
in = ck_get_rate(CK_PARENT(ck));
bits = (reg & (3 << shift)) >> shift;
return (in / bits2div[bits]);
}
int
ck_get_rate(ck_t ck)
{
int ret = 0;
ck_t parent;
if (!CK_IN_RANGE(ck)) {
ret = -EINVAL;
goto exit;
}
switch (ck) {
case OMAP_CK_GEN1:
ret = __ck_get_pll_rate(ck);
break;
case OMAP_CLKIN:
ret = source_clock;
break;
case OMAP_MPUXOR_CK:
case OMAP_CK_GEN2:
case OMAP_CK_GEN3:
case OMAP_ARM_GPIO_CK:
ret = ck_get_rate(CK_PARENT(ck));
break;
case OMAP_ARM_CK:
case OMAP_MPUPER_CK:
case OMAP_DSP_CK:
case OMAP_DSPMMU_CK:
case OMAP_LCD_CK:
case OMAP_TC_CK:
case OMAP_DMA_CK:
case OMAP_API_CK:
case OMAP_HSAB_CK:
case OMAP_LBFREE_CK:
case OMAP_LB_CK:
ret = __ck_get_clkm_rate(ck);
break;
case OMAP_MPUTIM_CK:
ck_get_input(ck, &parent);
ret = ck_get_rate(parent);
break;
case OMAP_MPUWD_CK:
/* Note that this evaluates to zero if source_clock is 12MHz. */
ret = source_clock / 14;
break;
default:
ret = -EINVAL;
break;
}
exit:
return ret;
}
int
ck_enable(ck_t ck)
{
unsigned short reg;
int ret = -EINVAL, shift;
unsigned long flags;
if (!CK_IN_RANGE(ck))
goto exit;
if (ck_debug)
printk(KERN_DEBUG "%s: %s\n", __FUNCTION__, CK_NAME(ck));
ret = 0;
if (!CK_CAN_DISABLE(ck))
/* Then it must be on... */
goto exit;
spin_lock_irqsave(&clock_lock, flags);
reg = omap_readw(CK_ENABLE_REG(ck));
shift = CK_ENABLE_SHIFT(ck);
reg |= (1 << shift);
omap_writew(reg, CK_ENABLE_REG(ck));
spin_unlock_irqrestore(&clock_lock, flags);
exit:
return ret;
}
int
ck_disable(ck_t ck)
{
unsigned short reg;
int ret = -EINVAL, shift;
unsigned long flags;
if (!CK_IN_RANGE(ck))
goto exit;
if (ck_debug)
printk(KERN_DEBUG "%s: %s\n", __FUNCTION__, CK_NAME(ck));
if (!CK_CAN_DISABLE(ck))
goto exit;
ret = 0;
if (ck == OMAP_CLKIN)
return -EINVAL;
spin_lock_irqsave(&clock_lock, flags);
reg = omap_readw(CK_ENABLE_REG(ck));
shift = CK_ENABLE_SHIFT(ck);
reg &= ~(1 << shift);
omap_writew(reg, CK_ENABLE_REG(ck));
spin_unlock_irqrestore(&clock_lock, flags);
exit:
return ret;
}
int ck_valid_rate(int rate)
{
return test_bit(rate, (unsigned long *)&ck_valid_table);
}
static void
__ck_make_lookup_table(void)
{
__u8 m, d;
memset(ck_valid_table, 0, sizeof (ck_valid_table));
for (m = 1; m < 32; m++)
for (d = 1; d < 5; d++) {
int rate = ((source_clock * m) / (d));
if (rate > CK_MAX_PLL_FREQ)
continue;
if (test_bit(rate, (unsigned long *)&ck_valid_table))
continue;
set_bit(rate, (unsigned long *)&ck_valid_table);
ck_lookup_table[rate - 1] = (m << 2) | (d - 1);
}
}
int __init
init_ck(void)
{
const struct omap_clock_info *info;
int crystal_type = 0; /* Default 12 MHz */
__ck_make_lookup_table();
info = omap_get_per_info(OMAP_TAG_CLOCK, struct omap_clock_info);
if (info != NULL) {
if (!cpu_is_omap1510())
crystal_type = info->system_clock_type;
}
/* We want to be in syncronous scalable mode */
omap_writew(0x1000, ARM_SYSST);
#if defined(CONFIG_OMAP_ARM_30MHZ)
omap_writew(0x1555, ARM_CKCTL);
omap_writew(0x2290, DPLL_CTL_REG);
#elif defined(CONFIG_OMAP_ARM_60MHZ)
omap_writew(0x1005, ARM_CKCTL);
omap_writew(0x2290, DPLL_CTL_REG);
#elif defined(CONFIG_OMAP_ARM_96MHZ)
omap_writew(0x1005, ARM_CKCTL);
omap_writew(0x2410, DPLL_CTL_REG);
#elif defined(CONFIG_OMAP_ARM_120MHZ)
omap_writew(0x110a, ARM_CKCTL);
omap_writew(0x2510, DPLL_CTL_REG);
#elif defined(CONFIG_OMAP_ARM_168MHZ)
omap_writew(0x110f, ARM_CKCTL);
omap_writew(0x2710, DPLL_CTL_REG);
#elif defined(CONFIG_OMAP_ARM_182MHZ) && defined(CONFIG_ARCH_OMAP730)
omap_writew(0x250E, ARM_CKCTL);
omap_writew(0x2710, DPLL_CTL_REG);
#elif defined(CONFIG_OMAP_ARM_192MHZ) && (defined(CONFIG_ARCH_OMAP1610) || defined(CONFIG_ARCH_OMAP5912))
omap_writew(0x150f, ARM_CKCTL);
if (crystal_type == 2) {
source_clock = 13; /* MHz */
omap_writew(0x2510, DPLL_CTL_REG);
} else
omap_writew(0x2810, DPLL_CTL_REG);
#elif defined(CONFIG_OMAP_ARM_195MHZ) && defined(CONFIG_ARCH_OMAP730)
omap_writew(0x250E, ARM_CKCTL);
omap_writew(0x2790, DPLL_CTL_REG);
#else
#error "OMAP MHZ not set, please run make xconfig"
#endif
#ifdef CONFIG_MACH_OMAP_PERSEUS2
/* Select slicer output as OMAP input clock */
omap_writew(omap_readw(OMAP730_PCC_UPLD_CTRL_REG) & ~0x1, OMAP730_PCC_UPLD_CTRL_REG);
#endif
/* Turn off some other junk the bootloader might have turned on */
/* Turn off DSP, ARM_INTHCK, ARM_TIMXO */
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
*/
ck_enable(OMAP_MPUPER_CK);
ck_enable(OMAP_ARM_GPIO_CK);
ck_enable(OMAP_MPUXOR_CK);
//ck_set_rate(OMAP_MPUTIM_CK, OMAP_CLKIN);
ck_enable(OMAP_MPUTIM_CK);
start_mputimer1(0xffffffff);
return 0;
}
EXPORT_SYMBOL(ck_get_rate);
EXPORT_SYMBOL(ck_set_rate);
EXPORT_SYMBOL(ck_enable);
EXPORT_SYMBOL(ck_disable);
![[BACK]](/icons/back.gif){kind=icon}
Return to clocks.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [Development] / linux-2.6-xfs / arch / arm / mach-omap