IMX: introduce clock API

This patch introduces the clock API for i.MX and converts all
in-Kernel drivers to use it.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
This commit is contained in:
Sascha Hauer 2008-07-05 10:02:46 +02:00 committed by Robert Schwebel
parent dbff4e9ea2
commit 38a41fdf94
9 changed files with 308 additions and 110 deletions

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@ -4,7 +4,7 @@
# Object file lists.
obj-y += irq.o time.o dma.o generic.o
obj-y += irq.o time.o dma.o generic.o clock.o
obj-$(CONFIG_CPU_FREQ_IMX) += cpufreq.o

205
arch/arm/mach-imx/clock.c Normal file
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@ -0,0 +1,205 @@
/*
* Copyright (C) 2008 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
*
* 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 program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/list.h>
#include <linux/math64.h>
#include <linux/err.h>
#include <asm/io.h>
#include <asm/arch/imx-regs.h>
/*
* Very simple approach: We can't disable clocks, so we do
* not need refcounting
*/
struct clk {
struct list_head node;
const char *name;
unsigned long (*get_rate)(void);
};
/*
* get the system pll clock in Hz
*
* mfi + mfn / (mfd +1)
* f = 2 * f_ref * --------------------
* pd + 1
*/
static unsigned long imx_decode_pll(unsigned int pll, u32 f_ref)
{
unsigned long long ll;
unsigned long quot;
u32 mfi = (pll >> 10) & 0xf;
u32 mfn = pll & 0x3ff;
u32 mfd = (pll >> 16) & 0x3ff;
u32 pd = (pll >> 26) & 0xf;
mfi = mfi <= 5 ? 5 : mfi;
ll = 2 * (unsigned long long)f_ref *
((mfi << 16) + (mfn << 16) / (mfd + 1));
quot = (pd + 1) * (1 << 16);
ll += quot / 2;
do_div(ll, quot);
return (unsigned long)ll;
}
static unsigned long imx_get_system_clk(void)
{
u32 f_ref = (CSCR & CSCR_SYSTEM_SEL) ? 16000000 : (CLK32 * 512);
return imx_decode_pll(SPCTL0, f_ref);
}
static unsigned long imx_get_mcu_clk(void)
{
return imx_decode_pll(MPCTL0, CLK32 * 512);
}
/*
* get peripheral clock 1 ( UART[12], Timer[12], PWM )
*/
static unsigned long imx_get_perclk1(void)
{
return imx_get_system_clk() / (((PCDR) & 0xf)+1);
}
/*
* get peripheral clock 2 ( LCD, SD, SPI[12] )
*/
static unsigned long imx_get_perclk2(void)
{
return imx_get_system_clk() / (((PCDR>>4) & 0xf)+1);
}
/*
* get peripheral clock 3 ( SSI )
*/
static unsigned long imx_get_perclk3(void)
{
return imx_get_system_clk() / (((PCDR>>16) & 0x7f)+1);
}
/*
* get hclk ( SDRAM, CSI, Memory Stick, I2C, DMA )
*/
static unsigned long imx_get_hclk(void)
{
return imx_get_system_clk() / (((CSCR>>10) & 0xf)+1);
}
static struct clk clk_system_clk = {
.name = "system_clk",
.get_rate = imx_get_system_clk,
};
static struct clk clk_hclk = {
.name = "hclk",
.get_rate = imx_get_hclk,
};
static struct clk clk_mcu_clk = {
.name = "mcu_clk",
.get_rate = imx_get_mcu_clk,
};
static struct clk clk_perclk1 = {
.name = "perclk1",
.get_rate = imx_get_perclk1,
};
static struct clk clk_uart_clk = {
.name = "uart_clk",
.get_rate = imx_get_perclk1,
};
static struct clk clk_perclk2 = {
.name = "perclk2",
.get_rate = imx_get_perclk2,
};
static struct clk clk_perclk3 = {
.name = "perclk3",
.get_rate = imx_get_perclk3,
};
static struct clk *clks[] = {
&clk_perclk1,
&clk_perclk2,
&clk_perclk3,
&clk_system_clk,
&clk_hclk,
&clk_mcu_clk,
&clk_uart_clk,
};
static LIST_HEAD(clocks);
static DEFINE_MUTEX(clocks_mutex);
struct clk *clk_get(struct device *dev, const char *id)
{
struct clk *p, *clk = ERR_PTR(-ENOENT);
mutex_lock(&clocks_mutex);
list_for_each_entry(p, &clocks, node) {
if (!strcmp(p->name, id)) {
clk = p;
goto found;
}
}
found:
mutex_unlock(&clocks_mutex);
return clk;
}
void clk_put(struct clk *clk)
{
}
int clk_enable(struct clk *clk)
{
return 0;
}
void clk_disable(struct clk *clk)
{
}
unsigned long clk_get_rate(struct clk *clk)
{
return clk->get_rate();
}
int imx_clocks_init(void)
{
int i;
mutex_lock(&clocks_mutex);
for (i = 0; i < ARRAY_SIZE(clks); i++)
list_add(&clks[i]->node, &clocks);
mutex_unlock(&clocks_mutex);
return 0;
}

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@ -32,6 +32,8 @@
#include <linux/types.h>
#include <linux/init.h>
#include <linux/cpufreq.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <asm/system.h>
#include <asm/hardware.h>
@ -52,6 +54,8 @@
static u32 mpctl0_at_boot;
static u32 bclk_div_at_boot;
static struct clk *system_clk, *mcu_clk;
static void imx_set_async_mode(void)
{
adjust_cr(CR_920T_CLOCK_MODE, CR_920T_ASYNC_MODE);
@ -160,10 +164,10 @@ static unsigned int imx_get_speed(unsigned int cpu)
cr = get_cr();
if((cr & CR_920T_CLOCK_MODE) == CR_920T_FASTBUS_MODE) {
freq = imx_get_system_clk();
freq = clk_get_rate(system_clk);
freq = (freq + bclk_div/2) / bclk_div;
} else {
freq = imx_get_mcu_clk();
freq = clk_get_rate(mcu_clk);
if (cscr & CSCR_MPU_PRESC)
freq /= 2;
}
@ -201,7 +205,7 @@ static int imx_set_target(struct cpufreq_policy *policy,
pr_debug(KERN_DEBUG "imx: requested frequency %ld Hz, mpctl0 at boot 0x%08x\n",
freq, mpctl0_at_boot);
sysclk = imx_get_system_clk();
sysclk = clk_get_rate(system_clk);
if (freq > sysclk / bclk_div_at_boot + 1000000) {
freq = imx_compute_mpctl(&mpctl0, mpctl0_at_boot, CLK32 * 512, freq, relation);
@ -290,6 +294,16 @@ static int __init imx_cpufreq_init(void)
bclk_div_at_boot = __mfld2val(CSCR_BCLK_DIV, CSCR) + 1;
mpctl0_at_boot = 0;
system_clk = clk_get(NULL, "system_clk");
if (IS_ERR(system_clk))
return PTR_ERR(system_clk);
mcu_clk = clk_get(NULL, "mcu_clk");
if (IS_ERR(mcu_clk)) {
clk_put(system_clk);
return PTR_ERR(mcu_clk);
}
if((CSCR & CSCR_MPEN) &&
((get_cr() & CR_920T_CLOCK_MODE) != CR_920T_FASTBUS_MODE))
mpctl0_at_boot = MPCTL0;

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@ -214,82 +214,6 @@ int imx_irq_to_gpio(unsigned irq)
EXPORT_SYMBOL(imx_irq_to_gpio);
/*
* get the system pll clock in Hz
*
* mfi + mfn / (mfd +1)
* f = 2 * f_ref * --------------------
* pd + 1
*/
static unsigned int imx_decode_pll(unsigned int pll, u32 f_ref)
{
unsigned long long ll;
unsigned long quot;
u32 mfi = (pll >> 10) & 0xf;
u32 mfn = pll & 0x3ff;
u32 mfd = (pll >> 16) & 0x3ff;
u32 pd = (pll >> 26) & 0xf;
mfi = mfi <= 5 ? 5 : mfi;
ll = 2 * (unsigned long long)f_ref * ( (mfi<<16) + (mfn<<16) / (mfd+1) );
quot = (pd+1) * (1<<16);
ll += quot / 2;
do_div(ll, quot);
return (unsigned int) ll;
}
unsigned int imx_get_system_clk(void)
{
u32 f_ref = (CSCR & CSCR_SYSTEM_SEL) ? 16000000 : (CLK32 * 512);
return imx_decode_pll(SPCTL0, f_ref);
}
EXPORT_SYMBOL(imx_get_system_clk);
unsigned int imx_get_mcu_clk(void)
{
return imx_decode_pll(MPCTL0, CLK32 * 512);
}
EXPORT_SYMBOL(imx_get_mcu_clk);
/*
* get peripheral clock 1 ( UART[12], Timer[12], PWM )
*/
unsigned int imx_get_perclk1(void)
{
return imx_get_system_clk() / (((PCDR) & 0xf)+1);
}
EXPORT_SYMBOL(imx_get_perclk1);
/*
* get peripheral clock 2 ( LCD, SD, SPI[12] )
*/
unsigned int imx_get_perclk2(void)
{
return imx_get_system_clk() / (((PCDR>>4) & 0xf)+1);
}
EXPORT_SYMBOL(imx_get_perclk2);
/*
* get peripheral clock 3 ( SSI )
*/
unsigned int imx_get_perclk3(void)
{
return imx_get_system_clk() / (((PCDR>>16) & 0x7f)+1);
}
EXPORT_SYMBOL(imx_get_perclk3);
/*
* get hclk ( SDRAM, CSI, Memory Stick, I2C, DMA )
*/
unsigned int imx_get_hclk(void)
{
return imx_get_system_clk() / (((CSCR>>10) & 0xf)+1);
}
EXPORT_SYMBOL(imx_get_hclk);
static struct resource imx_mmc_resources[] = {
[0] = {
.start = 0x00214000,

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@ -17,6 +17,7 @@
#include <linux/time.h>
#include <linux/clocksource.h>
#include <linux/clockchips.h>
#include <linux/clk.h>
#include <asm/hardware.h>
#include <asm/io.h>
@ -86,10 +87,10 @@ static struct clocksource clocksource_imx = {
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
static int __init imx_clocksource_init(void)
static int __init imx_clocksource_init(unsigned long rate)
{
clocksource_imx.mult =
clocksource_hz2mult(imx_get_perclk1(), clocksource_imx.shift);
clocksource_hz2mult(rate, clocksource_imx.shift);
clocksource_register(&clocksource_imx);
return 0;
@ -174,9 +175,9 @@ static struct clock_event_device clockevent_imx = {
.rating = 200,
};
static int __init imx_clockevent_init(void)
static int __init imx_clockevent_init(unsigned long rate)
{
clockevent_imx.mult = div_sc(imx_get_perclk1(), NSEC_PER_SEC,
clockevent_imx.mult = div_sc(rate, NSEC_PER_SEC,
clockevent_imx.shift);
clockevent_imx.max_delta_ns =
clockevent_delta2ns(0xfffffffe, &clockevent_imx);
@ -190,13 +191,23 @@ static int __init imx_clockevent_init(void)
return 0;
}
extern int imx_clocks_init(void);
static void __init imx_timer_init(void)
{
imx_timer_hardware_init();
imx_clocksource_init();
struct clk *clk;
unsigned long rate;
imx_clockevent_init();
imx_clocks_init();
clk = clk_get(NULL, "perclk1");
clk_enable(clk);
rate = clk_get_rate(clk);
imx_timer_hardware_init();
imx_clocksource_init(rate);
imx_clockevent_init(rate);
/*
* Make irqs happen for the system timer

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@ -42,6 +42,7 @@
#include <linux/mmc/host.h>
#include <linux/mmc/card.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <asm/dma.h>
#include <asm/io.h>
@ -92,6 +93,8 @@ struct imxmci_host {
unsigned char actual_bus_width;
int prev_cmd_code;
struct clk *clk;
};
#define IMXMCI_PEND_IRQ_b 0
@ -841,7 +844,7 @@ static void imxmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
/* The prescaler is 5 for PERCLK2 equal to 96MHz
* then 96MHz / 5 = 19.2 MHz
*/
clk=imx_get_perclk2();
clk = clk_get_rate(host->clk);
prescaler=(clk+(CLK_RATE*7)/8)/CLK_RATE;
switch(prescaler) {
case 0:
@ -994,6 +997,13 @@ static int imxmci_probe(struct platform_device *pdev)
host->res = r;
host->irq = irq;
host->clk = clk_get(&pdev->dev, "perclk2");
if (IS_ERR(host->clk)) {
ret = PTR_ERR(host->clk);
goto out;
}
clk_enable(host->clk);
imx_gpio_mode(PB8_PF_SD_DAT0);
imx_gpio_mode(PB9_PF_SD_DAT1);
imx_gpio_mode(PB10_PF_SD_DAT2);
@ -1053,6 +1063,10 @@ out:
imx_dma_free(host->dma);
host->dma_allocated=0;
}
if (host->clk) {
clk_disable(host->clk);
clk_put(host->clk);
}
}
if (mmc)
mmc_free_host(mmc);
@ -1082,6 +1096,9 @@ static int imxmci_remove(struct platform_device *pdev)
tasklet_kill(&host->tasklet);
clk_disable(host->clk);
clk_put(host->clk);
release_resource(host->res);
mmc_free_host(mmc);

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@ -40,6 +40,7 @@
#include <linux/tty_flip.h>
#include <linux/serial_core.h>
#include <linux/serial.h>
#include <linux/clk.h>
#include <asm/io.h>
#include <asm/irq.h>
@ -184,6 +185,7 @@ struct imx_port {
unsigned int old_status;
int txirq,rxirq,rtsirq;
int have_rtscts:1;
struct clk *clk;
};
/*
@ -479,7 +481,8 @@ static int imx_setup_ufcr(struct imx_port *sport, unsigned int mode)
* RFDIV is set such way to satisfy requested uartclk value
*/
val = TXTL << 10 | RXTL;
ufcr_rfdiv = (imx_get_perclk1() + sport->port.uartclk / 2) / sport->port.uartclk;
ufcr_rfdiv = (clk_get_rate(sport->clk) + sport->port.uartclk / 2)
/ sport->port.uartclk;
if(!ufcr_rfdiv)
ufcr_rfdiv = 1;
@ -916,7 +919,7 @@ imx_console_get_options(struct imx_port *sport, int *baud,
else
ucfr_rfdiv = 6 - ucfr_rfdiv;
uartclk = imx_get_perclk1();
uartclk = clk_get_rate(sport->clk);
uartclk /= ucfr_rfdiv;
{ /*
@ -1054,7 +1057,15 @@ static int serial_imx_probe(struct platform_device *pdev)
init_timer(&sport->timer);
sport->timer.function = imx_timeout;
sport->timer.data = (unsigned long)sport;
sport->port.uartclk = imx_get_perclk1();
sport->clk = clk_get(&pdev->dev, "uart_clk");
if (IS_ERR(sport->clk)) {
ret = PTR_ERR(sport->clk);
goto unmap;
}
clk_enable(sport->clk);
sport->port.uartclk = clk_get_rate(sport->clk);
imx_ports[pdev->id] = sport;
@ -1069,6 +1080,8 @@ static int serial_imx_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, &sport->port);
return 0;
unmap:
iounmap(sport->port.membase);
free:
kfree(sport);
@ -1084,8 +1097,12 @@ static int serial_imx_remove(struct platform_device *pdev)
platform_set_drvdata(pdev, NULL);
if (sport)
if (sport) {
uart_remove_one_port(&imx_reg, &sport->port);
clk_put(sport->clk);
}
clk_disable(sport->clk);
if (pdata->exit)
pdata->exit(pdev);

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@ -29,6 +29,7 @@
#include <linux/spi/spi.h>
#include <linux/workqueue.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <asm/io.h>
#include <asm/irq.h>
@ -250,6 +251,8 @@ struct driver_data {
int tx_dma_needs_unmap;
size_t tx_map_len;
u32 dummy_dma_buf ____cacheline_aligned;
struct clk *clk;
};
/* Runtime state */
@ -855,15 +858,15 @@ static irqreturn_t spi_int(int irq, void *dev_id)
return drv_data->transfer_handler(drv_data);
}
static inline u32 spi_speed_hz(u32 data_rate)
static inline u32 spi_speed_hz(struct driver_data *drv_data, u32 data_rate)
{
return imx_get_perclk2() / (4 << ((data_rate) >> 13));
return clk_get_rate(drv_data->clk) / (4 << ((data_rate) >> 13));
}
static u32 spi_data_rate(u32 speed_hz)
static u32 spi_data_rate(struct driver_data *drv_data, u32 speed_hz)
{
u32 div;
u32 quantized_hz = imx_get_perclk2() >> 2;
u32 quantized_hz = clk_get_rate(drv_data->clk) >> 2;
for (div = SPI_PERCLK2_DIV_MIN;
div <= SPI_PERCLK2_DIV_MAX;
@ -947,7 +950,7 @@ static void pump_transfers(unsigned long data)
tmp = transfer->speed_hz;
if (tmp == 0)
tmp = chip->max_speed_hz;
tmp = spi_data_rate(tmp);
tmp = spi_data_rate(drv_data, tmp);
u32_EDIT(control, SPI_CONTROL_DATARATE, tmp);
writel(control, regs + SPI_CONTROL);
@ -1109,7 +1112,7 @@ static int transfer(struct spi_device *spi, struct spi_message *msg)
msg->actual_length = 0;
/* Per transfer setup check */
min_speed_hz = spi_speed_hz(SPI_CONTROL_DATARATE_MIN);
min_speed_hz = spi_speed_hz(drv_data, SPI_CONTROL_DATARATE_MIN);
max_speed_hz = spi->max_speed_hz;
list_for_each_entry(trans, &msg->transfers, transfer_list) {
tmp = trans->bits_per_word;
@ -1176,6 +1179,7 @@ msg_rejected:
applied and notified to the calling driver. */
static int setup(struct spi_device *spi)
{
struct driver_data *drv_data = spi_master_get_devdata(spi->master);
struct spi_imx_chip *chip_info;
struct chip_data *chip;
int first_setup = 0;
@ -1304,14 +1308,14 @@ static int setup(struct spi_device *spi)
chip->n_bytes = (tmp <= 8) ? 1 : 2;
/* SPI datarate */
tmp = spi_data_rate(spi->max_speed_hz);
tmp = spi_data_rate(drv_data, spi->max_speed_hz);
if (tmp == SPI_CONTROL_DATARATE_BAD) {
status = -EINVAL;
dev_err(&spi->dev,
"setup - "
"HW min speed (%d Hz) exceeds required "
"max speed (%d Hz)\n",
spi_speed_hz(SPI_CONTROL_DATARATE_MIN),
spi_speed_hz(drv_data, SPI_CONTROL_DATARATE_MIN),
spi->max_speed_hz);
if (first_setup)
goto err_first_setup;
@ -1321,7 +1325,7 @@ static int setup(struct spi_device *spi)
} else {
u32_EDIT(chip->control, SPI_CONTROL_DATARATE, tmp);
/* Actual rounded max_speed_hz */
tmp = spi_speed_hz(tmp);
tmp = spi_speed_hz(drv_data, tmp);
spi->max_speed_hz = tmp;
chip->max_speed_hz = tmp;
}
@ -1352,7 +1356,7 @@ static int setup(struct spi_device *spi)
chip->period & SPI_PERIOD_WAIT,
spi->mode,
spi->bits_per_word,
spi_speed_hz(SPI_CONTROL_DATARATE_MIN),
spi_speed_hz(drv_data, SPI_CONTROL_DATARATE_MIN),
spi->max_speed_hz);
return status;
@ -1465,6 +1469,14 @@ static int __init spi_imx_probe(struct platform_device *pdev)
goto err_no_pdata;
}
drv_data->clk = clk_get(&pdev->dev, "perclk2");
if (IS_ERR(drv_data->clk)) {
dev_err(&pdev->dev, "probe - cannot get get\n");
status = PTR_ERR(drv_data->clk);
goto err_no_clk;
}
clk_enable(drv_data->clk);
/* Allocate master with space for drv_data */
master = spi_alloc_master(dev, sizeof(struct driver_data));
if (!master) {
@ -1623,6 +1635,9 @@ err_no_iores:
spi_master_put(master);
err_no_pdata:
clk_disable(drv_data->clk);
clk_put(drv_data->clk);
err_no_clk:
err_no_mem:
return status;
}
@ -1662,6 +1677,9 @@ static int __exit spi_imx_remove(struct platform_device *pdev)
if (irq >= 0)
free_irq(irq, drv_data);
clk_disable(drv_data->clk);
clk_put(drv_data->clk);
/* Release map resources */
iounmap(drv_data->regs);
release_resource(drv_data->ioarea);

View File

@ -73,14 +73,6 @@
*/
extern void imx_gpio_mode( int gpio_mode );
/* get frequencies in Hz */
extern unsigned int imx_get_system_clk(void);
extern unsigned int imx_get_mcu_clk(void);
extern unsigned int imx_get_perclk1(void); /* UART[12], Timer[12], PWM */
extern unsigned int imx_get_perclk2(void); /* LCD, SD, SPI[12] */
extern unsigned int imx_get_perclk3(void); /* SSI */
extern unsigned int imx_get_hclk(void); /* SDRAM, CSI, Memory Stick,*/
/* I2C, DMA */
#endif
#define MAXIRQNUM 62