diff options
author | Heiko St?bner <heiko@sntech.de> | 2011-10-14 10:08:56 +0400 |
---|---|---|
committer | Kukjin Kim <kgene.kim@samsung.com> | 2011-10-14 10:15:49 +0400 |
commit | aab08eebdf87d3e6eda5c81f119423af63f5aee1 (patch) | |
tree | dc8b3182c00b3e4b4989d6c9a559153068804094 /arch/arm/plat-s3c24xx | |
parent | d9a3bfbd7e80ecf24d2322659d5c0542f9d95e78 (diff) | |
download | linux-aab08eebdf87d3e6eda5c81f119423af63f5aee1.tar.xz |
ARM: S3C2443: Move clk_arm and clk_armdiv to common code
The system-layout of the armdiv and armclk is common to
S3C2443/S3C2416/S3C2450 and only differs in the array of
possible dividers. Therefore it is possible to reuse the
clock definitions for all of these SoCs.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Diffstat (limited to 'arch/arm/plat-s3c24xx')
-rw-r--r-- | arch/arm/plat-s3c24xx/s3c2443-clock.c | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/arch/arm/plat-s3c24xx/s3c2443-clock.c b/arch/arm/plat-s3c24xx/s3c2443-clock.c index 3f2117b8c0d4..f9c5b0343cf3 100644 --- a/arch/arm/plat-s3c24xx/s3c2443-clock.c +++ b/arch/arm/plat-s3c24xx/s3c2443-clock.c @@ -160,10 +160,95 @@ static struct clk clk_prediv = { }, }; +/* armdiv + * + * this clock is sourced from msysclk and can have a number of + * divider values applied to it to then be fed into armclk. +*/ + static unsigned int *armdiv; static int nr_armdiv; static int armdivmask; +static unsigned long s3c2443_armclk_roundrate(struct clk *clk, + unsigned long rate) +{ + unsigned long parent = clk_get_rate(clk->parent); + unsigned long calc; + unsigned best = 256; /* bigger than any value */ + unsigned div; + int ptr; + + for (ptr = 0; ptr < nr_armdiv; ptr++) { + div = armdiv[ptr]; + calc = parent / div; + if (calc <= rate && div < best) + best = div; + } + + return parent / best; +} + +static int s3c2443_armclk_setrate(struct clk *clk, unsigned long rate) +{ + unsigned long parent = clk_get_rate(clk->parent); + unsigned long calc; + unsigned div; + unsigned best = 256; /* bigger than any value */ + int ptr; + int val = -1; + + for (ptr = 0; ptr < nr_armdiv; ptr++) { + div = armdiv[ptr]; + calc = parent / div; + if (calc <= rate && div < best) { + best = div; + val = ptr; + } + } + + if (val >= 0) { + unsigned long clkcon0; + + clkcon0 = __raw_readl(S3C2443_CLKDIV0); + clkcon0 &= ~armdivmask; + clkcon0 |= val << S3C2443_CLKDIV0_ARMDIV_SHIFT; + __raw_writel(clkcon0, S3C2443_CLKDIV0); + } + + return (val == -1) ? -EINVAL : 0; +} + +static struct clk clk_armdiv = { + .name = "armdiv", + .parent = &clk_msysclk.clk, + .ops = &(struct clk_ops) { + .round_rate = s3c2443_armclk_roundrate, + .set_rate = s3c2443_armclk_setrate, + }, +}; + +/* armclk + * + * this is the clock fed into the ARM core itself, from armdiv or from hclk. + */ + +static struct clk *clk_arm_sources[] = { + [0] = &clk_armdiv, + [1] = &clk_h, +}; + +static struct clksrc_clk clk_arm = { + .clk = { + .name = "armclk", + }, + .sources = &(struct clksrc_sources) { + .sources = clk_arm_sources, + .nr_sources = ARRAY_SIZE(clk_arm_sources), + }, + .reg_src = { .reg = S3C2443_CLKDIV0, .size = 1, .shift = 13 }, +}; + /* usbhost * * usb host bus-clock, usually 48MHz to provide USB bus clock timing @@ -462,6 +547,7 @@ static struct clk *clks[] __initdata = { &clk_ext, &clk_epll, &clk_usb_bus, + &clk_armdiv, }; static struct clksrc_clk *clksrcs[] __initdata = { @@ -471,6 +557,7 @@ static struct clksrc_clk *clksrcs[] __initdata = { &clk_epllref, &clk_esysclk, &clk_msysclk, + &clk_arm, }; void __init s3c2443_common_init_clocks(int xtal, pll_fn get_mpll, |