From bdbea34ddd2e52dc73f03e7ef7197d4c0da400d6 Mon Sep 17 00:00:00 2001 From: Ben Dooks Date: Mon, 28 Jan 2008 13:01:18 +0100 Subject: [ARM] 4778/1: S3C2412: Add armclk and init from DVS state Add armclk to the S3C2412 to indicate the current clock connected to the ARM core. Signed-off-by: Ben Dooks Signed-off-by: Russell King --- arch/arm/mach-s3c2412/clock.c | 50 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+) (limited to 'arch/arm') diff --git a/arch/arm/mach-s3c2412/clock.c b/arch/arm/mach-s3c2412/clock.c index 45899360189..42ccb5eb604 100644 --- a/arch/arm/mach-s3c2412/clock.c +++ b/arch/arm/mach-s3c2412/clock.c @@ -234,6 +234,45 @@ static struct clk clk_msysclk = { .set_parent = s3c2412_setparent_msysclk, }; +static int s3c2412_setparent_armclk(struct clk *clk, struct clk *parent) +{ + unsigned long flags; + unsigned long clkdiv; + unsigned long dvs; + + /* Note, we current equate fclk andf msysclk for S3C2412 */ + + if (parent == &clk_msysclk || parent == &clk_f) + dvs = 0; + else if (parent == &clk_h) + dvs = S3C2412_CLKDIVN_DVSEN; + else + return -EINVAL; + + clk->parent = parent; + + /* update this under irq lockdown, clkdivn is not protected + * by the clock system. */ + + local_irq_save(flags); + + clkdiv = __raw_readl(S3C2410_CLKDIVN); + clkdiv &= ~S3C2412_CLKDIVN_DVSEN; + clkdiv |= dvs; + __raw_writel(clkdiv, S3C2410_CLKDIVN); + + local_irq_restore(flags); + + return 0; +} + +static struct clk clk_armclk = { + .name = "armclk", + .id = -1, + .parent = &clk_msysclk, + .set_parent = s3c2412_setparent_armclk, +}; + /* these next clocks have an divider immediately after them, * so we can register them with their divider and leave out the * intermediate clock stage @@ -630,11 +669,13 @@ static struct clk *clks[] __initdata = { &clk_erefclk, &clk_urefclk, &clk_mrefclk, + &clk_armclk, }; int __init s3c2412_baseclk_add(void) { unsigned long clkcon = __raw_readl(S3C2410_CLKCON); + unsigned int dvs; struct clk *clkp; int ret; int ptr; @@ -655,6 +696,15 @@ int __init s3c2412_baseclk_add(void) } } + /* set the dvs state according to what we got at boot time */ + + dvs = __raw_readl(S3C2410_CLKDIVN) & S3C2412_CLKDIVN_DVSEN; + + if (dvs) + clk_armclk.parent = &clk_h; + + printk(KERN_INFO "S3C2412: DVS is %s\n", dvs ? "on" : "off"); + /* ensure usb bus clock is within correct rate of 48MHz */ if (clk_get_rate(&clk_usb_bus) != (48 * 1000 * 1000)) { -- cgit v1.2.3-70-g09d2