redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

[ARM] 4967/1: Adds functions to set clkout rate for Samsung S3C2410 

This patch adds functions to set clkout rate for Samsung S3C2410
This patch supersedes 4884/1, that contained an error

Comments from Ben Dooks:

 Note, looks like this needs to be applied before 4882/1

Signed-off-by: Davide Rizzo <davide@elpa.it>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
hifive-unleashed-5.1
Davide Rizzo 2008-04-12 15:08:15 +01:00 committed by Russell King
parent 79b34afa68
commit eb1f7d10d6
1 changed files with 56 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

56
arch/arm/plat-s3c24xx/clock.c
View File

@ -332,6 +332,58 @@ static int s3c24xx_dclk_setparent(struct clk *clk, struct clk *parent)
return 0;
}
static unsigned long s3c24xx_calc_div(struct clk *clk, unsigned long rate)
{
unsigned long div;
if ((rate == 0) || !clk->parent)
return 0;
div = clk_get_rate(clk->parent) / rate;
if (div < 2)
div = 2;
else if (div > 16)
div = 16;
return div;
}
static unsigned long s3c24xx_round_dclk_rate(struct clk *clk,
unsigned long rate)
{
unsigned long div = s3c24xx_calc_div(clk, rate);
if (div == 0)
return 0;
return clk_get_rate(clk->parent) / div;
}
static int s3c24xx_set_dclk_rate(struct clk *clk, unsigned long rate)
{
unsigned long mask, data, div = s3c24xx_calc_div(clk, rate);
if (div == 0)
return -EINVAL;
if (clk == &s3c24xx_dclk0) {
mask = S3C2410_DCLKCON_DCLK0_DIV_MASK |
S3C2410_DCLKCON_DCLK0_CMP_MASK;
data = S3C2410_DCLKCON_DCLK0_DIV(div) |
S3C2410_DCLKCON_DCLK0_CMP((div + 1) / 2);
} else if (clk == &s3c24xx_dclk1) {
mask = S3C2410_DCLKCON_DCLK1_DIV_MASK |
S3C2410_DCLKCON_DCLK1_CMP_MASK;
data = S3C2410_DCLKCON_DCLK1_DIV(div) |
S3C2410_DCLKCON_DCLK1_CMP((div + 1) / 2);
} else
return -EINVAL;
clk->rate = clk_get_rate(clk->parent) / div;
__raw_writel(((__raw_readl(S3C24XX_DCLKCON) & ~mask) | data),
S3C24XX_DCLKCON);
return clk->rate;
}
static int s3c24xx_clkout_setparent(struct clk *clk, struct clk *parent)
{
@ -378,6 +430,8 @@ struct clk s3c24xx_dclk0 = {
.ctrlbit = S3C2410_DCLKCON_DCLK0EN,
.enable = s3c24xx_dclk_enable,
.set_parent = s3c24xx_dclk_setparent,
.set_rate = s3c24xx_set_dclk_rate,
.round_rate = s3c24xx_round_dclk_rate,
};
struct clk s3c24xx_dclk1 = {
@ -386,6 +440,8 @@ struct clk s3c24xx_dclk1 = {
.ctrlbit = S3C2410_DCLKCON_DCLK0EN,
.enable = s3c24xx_dclk_enable,
.set_parent = s3c24xx_dclk_setparent,
.set_rate = s3c24xx_set_dclk_rate,
.round_rate = s3c24xx_round_dclk_rate,
};
struct clk s3c24xx_clkout0 = {