From: Hans de Goede Date: Sun, 7 Dec 2014 20:09:31 +0000 (+0100) Subject: sun6i: clock_set_pll5: Calculate k and m rather then hardcoding them X-Git-Tag: v2015.04-rc1~175 X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=1aac47bd1bf8f1f4a5f12bf7c8e06a18e5b649b4;p=oweals%2Fu-boot.git sun6i: clock_set_pll5: Calculate k and m rather then hardcoding them Our old hardcoded k and m values are based on PLL5 being configured in steps of 48 MHz, which is correct for sun6i where the DRAM PLL runs at twice the DRAM CLK, which is usually configured in 24 MHz step. But on the A23 (sun8i) the PLL5 runs at half the DRAM CLK, so we require 12 MHz steps. This commit adjusts clock_set_pll5 to automatically select the best k and m depending on the requested clk rate. Suggested-by: Siarhei Siamashka Signed-off-by: Hans de Goede Acked-by: Ian Campbell --- diff --git a/arch/arm/cpu/armv7/sunxi/clock_sun6i.c b/arch/arm/cpu/armv7/sunxi/clock_sun6i.c index 193e31459c..ad50dd90f3 100644 --- a/arch/arm/cpu/armv7/sunxi/clock_sun6i.c +++ b/arch/arm/cpu/armv7/sunxi/clock_sun6i.c @@ -148,13 +148,18 @@ void clock_set_pll5(unsigned int clk, bool sigma_delta_enable) { struct sunxi_ccm_reg * const ccm = (struct sunxi_ccm_reg *)SUNXI_CCM_BASE; - const int k = 2; - const int m = 1; + const int max_n = 32; + int k = 1, m = 2; if (sigma_delta_enable) writel(CCM_PLL5_PATTERN, &ccm->pll5_pattern_cfg); /* PLL5 rate = 24000000 * n * k / m */ + if (clk > 24000000 * k * max_n / m) { + m = 1; + if (clk > 24000000 * k * max_n / m) + k = 2; + } writel(CCM_PLL5_CTRL_EN | (sigma_delta_enable ? CCM_PLL5_CTRL_SIGMA_DELTA_EN : 0) | CCM_PLL5_CTRL_UPD |