[U-Boot] [PATCH 7/9] EXYNOS5: CLOCK: Modify MPLL clock out for Exynos5250 Rev 1.0
Joonyoung Shim
dofmind at gmail.com
Thu Jun 21 07:01:20 CEST 2012
Hi,
2012/6/20 Rajeshwari Shinde <rajeshwari.s at samsung.com>:
> MPLL clock-out of Exynos5250 Rev 1.0 is always at 1.6GHz.
> Adjust the divisor value to get 800MHz as needed by devices
> like UART etc
>
> Signed-off-by: Hatim Ali <hatim.rv at samsung.com>
> Signed-off-by: Rajeshwari Shinde <rajeshwari.s at samsung.com>
> ---
> arch/arm/cpu/armv7/exynos/clock.c | 12 +++++++++++-
> arch/arm/include/asm/arch-exynos/clock.h | 3 +++
> 2 files changed, 14 insertions(+), 1 deletions(-)
>
> diff --git a/arch/arm/cpu/armv7/exynos/clock.c b/arch/arm/cpu/armv7/exynos/clock.c
> index 330bd75..dbd5f11 100644
> --- a/arch/arm/cpu/armv7/exynos/clock.c
> +++ b/arch/arm/cpu/armv7/exynos/clock.c
> @@ -98,7 +98,7 @@ static unsigned long exynos5_get_pll_clk(int pllreg)
> struct exynos5_clock *clk =
> (struct exynos5_clock *)samsung_get_base_clock();
> unsigned long r, m, p, s, k = 0, mask, fout;
> - unsigned int freq;
> + unsigned int freq, pll_div2_sel, mpll_fout_sel;
>
> switch (pllreg) {
> case APLL:
> @@ -155,6 +155,16 @@ static unsigned long exynos5_get_pll_clk(int pllreg)
> fout = m * (freq / (p * (1 << (s - 1))));
> }
>
> + /* According to the user manual, in EVT1 MPLL always gives
> + * 1.6GHz clock, so divide by 2 to get 800MHz MPLL clock.*/
> + if (pllreg == MPLL) {
> + pll_div2_sel = readl(&clk->pll_div2_sel);
> + mpll_fout_sel = (pll_div2_sel >> MPLL_FOUT_SEL_SHIFT)
> + & MPLL_FOUT_SEL_MASK;
> + if (mpll_fout_sel == 0)
> + fout /= 2;
> + }
> +
I think BPLL also needs this.
--
- Joonyoung Shim
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