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[ARM] S3C64XX: Update TCFG for new timer divider settings. 

The S3C64XX series has a new TCFG divider setting to allow the clock
directly through, which means that we need to update the pwm-clock
code to cope with this.

Add <mach/pwm-clock.h> containing the specific code to deal with the
TCFG divider settings and provide any other per-arch data that the
pwm-clock driver needs to function.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
This commit is contained in:
Ben Dooks 2008-11-21 10:36:03 +00:00
parent 44539a7112
commit b09bcdd4c2
4 changed files with 129 additions and 29 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

56
arch/arm/mach-s3c6400/include/mach/pwm-clock.h Normal file
View File

@ -0,0 +1,56 @@
/* linux/arch/arm/mach-s3c6400/include/mach/pwm-clock.h
*
* Copyright 2008 Openmoko, Inc.
* Copyright 2008 Simtec Electronics
* Ben Dooks <ben@simtec.co.uk>
* http://armlinux.simtec.co.uk/
*
* S3C64xx - pwm clock and timer support
*/
/**
* pwm_cfg_src_is_tclk() - return whether the given mux config is a tclk
* @tcfg: The timer TCFG1 register bits shifted down to 0.
*
* Return true if the given configuration from TCFG1 is a TCLK instead
* any of the TDIV clocks.
*/
static inline int pwm_cfg_src_is_tclk(unsigned long tcfg)
{
return tcfg >= S3C64XX_TCFG1_MUX_TCLK;
}
/**
* tcfg_to_divisor() - convert tcfg1 setting to a divisor
* @tcfg1: The tcfg1 setting, shifted down.
*
* Get the divisor value for the given tcfg1 setting. We assume the
* caller has already checked to see if this is not a TCLK source.
*/
static inline unsigned long tcfg_to_divisor(unsigned long tcfg1)
{
return 1 << tcfg1;
}
/**
* pwm_tdiv_has_div1() - does the tdiv setting have a /1
*
* Return true if we have a /1 in the tdiv setting.
*/
static inline unsigned int pwm_tdiv_has_div1(void)
{
return 1;
}
/**
* pwm_tdiv_div_bits() - calculate TCFG1 divisor value.
* @div: The divisor to calculate the bit information for.
*
* Turn a divisor into the necessary bit field for TCFG1.
*/
static inline unsigned long pwm_tdiv_div_bits(unsigned int div)
{
return ilog2(div);
}
#define S3C_TCFG1_MUX_TCLK S3C64XX_TCFG1_MUX_TCLK

8
arch/arm/plat-s3c/include/plat/regs-timer.h
View File

@ -73,6 +73,14 @@
#define S3C2410_TCFG1_MUX_TCLK (4<<0)
#define S3C2410_TCFG1_MUX_MASK (15<<0)
#define S3C64XX_TCFG1_MUX_DIV1 (0<<0)
#define S3C64XX_TCFG1_MUX_DIV2 (1<<0)
#define S3C64XX_TCFG1_MUX_DIV4 (2<<0)
#define S3C64XX_TCFG1_MUX_DIV8 (3<<0)
#define S3C64XX_TCFG1_MUX_DIV16 (4<<0)
#define S3C64XX_TCFG1_MUX_TCLK (5<<0) /* 3 sets of TCLK */
#define S3C64XX_TCFG1_MUX_MASK (15<<0)
#define S3C2410_TCFG1_SHIFT(x) ((x) * 4)
/* for each timer, we have an count buffer, an compare buffer and

39
arch/arm/plat-s3c/pwm-clock.c
View File

@ -14,6 +14,7 @@
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/errno.h>
#include <linux/log2.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/io.h>
@ -26,6 +27,7 @@
#include <plat/cpu.h>
#include <plat/regs-timer.h>
#include <mach/pwm-clock.h>
/* Each of the timers 0 through 5 go through the following
* clock tree, with the inputs depending on the timers.
@ -166,11 +168,6 @@ static inline struct pwm_tdiv_clk *to_tdiv(struct clk *clk)
return container_of(clk, struct pwm_tdiv_clk, clk);
}
static inline unsigned long tcfg_to_divisor(unsigned long tcfg1)
{
return 1 << (1 + tcfg1);
}
static unsigned long clk_pwm_tdiv_get_rate(struct clk *clk)
{
unsigned long tcfg1 = __raw_readl(S3C2410_TCFG1);
@ -179,7 +176,7 @@ static unsigned long clk_pwm_tdiv_get_rate(struct clk *clk)
tcfg1 >>= S3C2410_TCFG1_SHIFT(clk->id);
tcfg1 &= S3C2410_TCFG1_MUX_MASK;
if (tcfg1 == S3C2410_TCFG1_MUX_TCLK)
if (pwm_cfg_src_is_tclk(tcfg1))
divisor = to_tdiv(clk)->divisor;
else
divisor = tcfg_to_divisor(tcfg1);
@ -196,7 +193,9 @@ static unsigned long clk_pwm_tdiv_round_rate(struct clk *clk,
parent_rate = clk_get_rate(clk->parent);
divisor = parent_rate / rate;
if (divisor <= 2)
if (divisor <= 1 && pwm_tdiv_has_div1())
divisor = 1;
else if (divisor <= 2)
divisor = 2;
else if (divisor <= 4)
divisor = 4;
@ -210,25 +209,7 @@ static unsigned long clk_pwm_tdiv_round_rate(struct clk *clk,
static unsigned long clk_pwm_tdiv_bits(struct pwm_tdiv_clk *divclk)
{
unsigned long bits;
switch (divclk->divisor) {
case 2:
bits = S3C2410_TCFG1_MUX_DIV2;
break;
case 4:
bits = S3C2410_TCFG1_MUX_DIV4;
break;
case 8:
bits = S3C2410_TCFG1_MUX_DIV8;
break;
case 16:
default:
bits = S3C2410_TCFG1_MUX_DIV16;
break;
}
return bits;
return pwm_tdiv_div_bits(divclk->divisor);
}
static void clk_pwm_tdiv_update(struct pwm_tdiv_clk *divclk)
@ -269,7 +250,7 @@ static int clk_pwm_tdiv_set_rate(struct clk *clk, unsigned long rate)
/* Update the current MUX settings if we are currently
* selected as the clock source for this clock. */
if (tcfg1 != S3C2410_TCFG1_MUX_TCLK)
if (!pwm_cfg_src_is_tclk(tcfg1))
clk_pwm_tdiv_update(divclk);
return 0;
@ -356,7 +337,7 @@ static int clk_pwm_tin_set_parent(struct clk *clk, struct clk *parent)
unsigned long shift = S3C2410_TCFG1_SHIFT(id);
if (parent == s3c24xx_pwmclk_tclk(id))
bits = S3C2410_TCFG1_MUX_TCLK << shift;
bits = S3C_TCFG1_MUX_TCLK << shift;
else if (parent == s3c24xx_pwmclk_tdiv(id))
bits = clk_pwm_tdiv_bits(to_tdiv(parent)) << shift;
else
@ -418,7 +399,7 @@ static __init int clk_pwm_tin_register(struct clk *pwm)
tcfg1 >>= S3C2410_TCFG1_SHIFT(id);
tcfg1 &= S3C2410_TCFG1_MUX_MASK;
if (tcfg1 == S3C2410_TCFG1_MUX_TCLK)
if (pwm_cfg_src_is_tclk(tcfg1))
parent = s3c24xx_pwmclk_tclk(id);
else
parent = s3c24xx_pwmclk_tdiv(id);

55
arch/arm/plat-s3c24xx/include/mach/pwm-clock.h Normal file
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@ -0,0 +1,55 @@
/* linux/arch/arm/plat-s3c24xx/include/mach/pwm-clock.h
*
* Copyright 2008 Simtec Electronics
* Ben Dooks <ben@simtec.co.uk>
* http://armlinux.simtec.co.uk/
*
* S3C24xx - pwm clock and timer support
*/
/**
* pwm_cfg_src_is_tclk() - return whether the given mux config is a tclk
* @cfg: The timer TCFG1 register bits shifted down to 0.
*
* Return true if the given configuration from TCFG1 is a TCLK instead
* any of the TDIV clocks.
*/
static inline int pwm_cfg_src_is_tclk(unsigned long tcfg)
{
return tcfg == S3C2410_TCFG1_MUX_TCLK;
}
/**
* tcfg_to_divisor() - convert tcfg1 setting to a divisor
* @tcfg1: The tcfg1 setting, shifted down.
*
* Get the divisor value for the given tcfg1 setting. We assume the
* caller has already checked to see if this is not a TCLK source.
*/
static inline unsigned long tcfg_to_divisor(unsigned long tcfg1)
{
return 1 << (1 + tcfg1);
}
/**
* pwm_tdiv_has_div1() - does the tdiv setting have a /1
*
* Return true if we have a /1 in the tdiv setting.
*/
static inline unsigned int pwm_tdiv_has_div1(void)
{
return 0;
}
/**
* pwm_tdiv_div_bits() - calculate TCFG1 divisor value.
* @div: The divisor to calculate the bit information for.
*
* Turn a divisor into the necessary bit field for TCFG1.
*/
static inline unsigned long pwm_tdiv_div_bits(unsigned int div)
{
return ilog2(div) - 1;
}
#define S3C_TCFG1_MUX_TCLK S3C2410_TCFG1_MUX_TCLK