From 41f23a09f32124322dc41bea7f65baff6e9b0ac5 Mon Sep 17 00:00:00 2001 From: Ben Dooks Date: Sat, 30 Jan 2010 11:14:14 +0200 Subject: ARM: S3C2443: Add set_rate and round_rate calls for armdiv clock Add set_rate and round_rate calls to armdiv for future use with cpu frequency scaling. Signed-off-by: Ben Dooks --- arch/arm/mach-s3c2443/clock.c | 93 +++++++++++++++++++++++++++++++++---------- 1 file changed, 73 insertions(+), 20 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/mach-s3c2443/clock.c b/arch/arm/mach-s3c2443/clock.c index 177719c7c26..62cd4eaee01 100644 --- a/arch/arm/mach-s3c2443/clock.c +++ b/arch/arm/mach-s3c2443/clock.c @@ -165,10 +165,83 @@ static struct clksrc_clk clk_msysclk = { * divider values applied to it to then be fed into armclk. */ +/* armdiv divisor table */ + +static unsigned int armdiv[16] = { + [S3C2443_CLKDIV0_ARMDIV_1 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 1, + [S3C2443_CLKDIV0_ARMDIV_2 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 2, + [S3C2443_CLKDIV0_ARMDIV_3 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 3, + [S3C2443_CLKDIV0_ARMDIV_4 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 4, + [S3C2443_CLKDIV0_ARMDIV_6 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 6, + [S3C2443_CLKDIV0_ARMDIV_8 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 8, + [S3C2443_CLKDIV0_ARMDIV_12 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 12, + [S3C2443_CLKDIV0_ARMDIV_16 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 16, +}; + +static inline unsigned int s3c2443_fclk_div(unsigned long clkcon0) +{ + clkcon0 &= S3C2443_CLKDIV0_ARMDIV_MASK; + + return armdiv[clkcon0 >> S3C2443_CLKDIV0_ARMDIV_SHIFT]; +} + +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 < ARRAY_SIZE(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 < ARRAY_SIZE(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 &= S3C2443_CLKDIV0_ARMDIV_MASK; + clkcon0 |= val << S3C2443_CLKDIV0_ARMDIV_SHIFT; + __raw_writel(clkcon0, S3C2443_CLKDIV0); + } + + return (val == -1) ? -EINVAL : 0; +} + static struct clk clk_armdiv = { .name = "armdiv", .id = -1, .parent = &clk_msysclk.clk, + .ops = &(struct clk_ops) { + .round_rate = s3c2443_armclk_roundrate, + .set_rate = s3c2443_armclk_setrate, + }, }; /* armclk @@ -619,26 +692,6 @@ static void __init s3c2443_clk_initparents(void) s3c_set_clksrc(init_list[ptr], true); } -/* armdiv divisor table */ - -static unsigned int armdiv[16] = { - [S3C2443_CLKDIV0_ARMDIV_1 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 1, - [S3C2443_CLKDIV0_ARMDIV_2 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 2, - [S3C2443_CLKDIV0_ARMDIV_3 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 3, - [S3C2443_CLKDIV0_ARMDIV_4 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 4, - [S3C2443_CLKDIV0_ARMDIV_6 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 6, - [S3C2443_CLKDIV0_ARMDIV_8 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 8, - [S3C2443_CLKDIV0_ARMDIV_12 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 12, - [S3C2443_CLKDIV0_ARMDIV_16 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 16, -}; - -static inline unsigned int s3c2443_fclk_div(unsigned long clkcon0) -{ - clkcon0 &= S3C2443_CLKDIV0_ARMDIV_MASK; - - return armdiv[clkcon0 >> S3C2443_CLKDIV0_ARMDIV_SHIFT]; -} - static inline unsigned long s3c2443_get_hdiv(unsigned long clkcon0) { clkcon0 &= S3C2443_CLKDIV0_HCLKDIV_MASK; -- cgit v1.2.3-70-g09d2