Patrick Georgi (patrick@georgi-clan.de) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/4442
-gerrit
commit 6cef89feee1d570c83c4f0490120c6b4e6b2a91a Author: David Hendricks dhendrix@chromium.org Date: Tue Aug 6 15:17:37 2013 -0700
exynos5xxx: use oscillator clock when changing ARM frequency
Switch ARM clock source when changing the APLL frequency to avoid stability issues.
This is ported from https://gerrit.chromium.org/gerrit/#/c/64189/5
Signed-off-by: David Hendricks dhendrix@chromium.org
Change-Id: I923107555e6d3287b3694cbf9e4bb548d3e5f4a8 Reviewed-on: https://gerrit.chromium.org/gerrit/64838 Reviewed-by: David Hendricks dhendrix@chromium.org Tested-by: David Hendricks dhendrix@chromium.org Commit-Queue: David Hendricks dhendrix@chromium.org --- src/cpu/samsung/exynos5250/clock_init.c | 6 ++++++ src/cpu/samsung/exynos5250/setup.h | 2 ++ src/cpu/samsung/exynos5420/clock_init.c | 12 ++++++++++++ src/cpu/samsung/exynos5420/setup.h | 3 +++ 4 files changed, 23 insertions(+)
diff --git a/src/cpu/samsung/exynos5250/clock_init.c b/src/cpu/samsung/exynos5250/clock_init.c index 2cfdaf4..bfcf844 100644 --- a/src/cpu/samsung/exynos5250/clock_init.c +++ b/src/cpu/samsung/exynos5250/clock_init.c @@ -102,6 +102,9 @@ void system_clock_init(struct mem_timings *mem, val = readl(&clk->div_stat_cpu1); } while (0 != val);
+ /* switch A15 clock source to OSC clock before changing APLL */ + clrbits_le32(&clk->src_cpu, APLL_FOUT); + /* Set APLL */ writel(APLL_CON1_VAL, &clk->apll_con1); val = set_pll(arm_clk_ratio->apll_mdiv, arm_clk_ratio->apll_pdiv, @@ -110,6 +113,9 @@ void system_clock_init(struct mem_timings *mem, while ((readl(&clk->apll_con0) & APLL_CON0_LOCKED) == 0) ;
+ /* now it is safe to switch to APLL */ + setbits_le32(&clk->src_cpu, APLL_FOUT); + /* Set MPLL */ writel(MPLL_CON1_VAL, &clk->mpll_con1); val = set_pll(mem->mpll_mdiv, mem->mpll_pdiv, mem->mpll_sdiv); diff --git a/src/cpu/samsung/exynos5250/setup.h b/src/cpu/samsung/exynos5250/setup.h index 2ed4f22..c65747b 100644 --- a/src/cpu/samsung/exynos5250/setup.h +++ b/src/cpu/samsung/exynos5250/setup.h @@ -38,6 +38,8 @@ struct exynos5_phy_control; #define TZPC8_BASE 0x10180000 #define TZPC9_BASE 0x10190000
+#define APLL_FOUT (1 << 0) + /* APLL_CON1 */ #define APLL_CON1_VAL (0x00203800)
diff --git a/src/cpu/samsung/exynos5420/clock_init.c b/src/cpu/samsung/exynos5420/clock_init.c index 069fd8f..b62ebe4 100644 --- a/src/cpu/samsung/exynos5420/clock_init.c +++ b/src/cpu/samsung/exynos5420/clock_init.c @@ -60,6 +60,9 @@ void system_clock_init(void) writel(HPM_RATIO, &clk->clk_div_cpu1); writel(CLK_DIV_CPU0_VAL, &clk->clk_div_cpu0);
+ /* switch A15 clock source to OSC clock before changing APLL */ + clrbits_le32(&clk->clk_src_cpu, APLL_FOUT); + /* Set APLL */ writel(APLL_CON1_VAL, &clk->apll_con1); val = set_pll(0xc8, 0x3, 0x1); @@ -67,9 +70,15 @@ void system_clock_init(void) while ((readl(&clk->apll_con0) & PLL_LOCKED) == 0) ;
+ /* now it is safe to switch to APLL */ + setbits_le32(&clk->clk_src_cpu, APLL_FOUT); + writel(SRC_KFC_HPM_SEL, &clk->clk_src_kfc); writel(CLK_DIV_KFC_VAL, &clk->clk_div_kfc0);
+ /* switch A7 clock source to OSC clock before changing KPLL */ + clrbits_le32(&clk->clk_src_kfc, KPLL_FOUT); + /* Set KPLL*/ writel(KPLL_CON1_VAL, &clk->kpll_con1); val = set_pll(0xc8, 0x2, 0x2); @@ -77,6 +86,9 @@ void system_clock_init(void) while ((readl(&clk->kpll_con0) & PLL_LOCKED) == 0) ;
+ /* now it is safe to switch to KPLL */ + setbits_le32(&clk->clk_src_kfc, KPLL_FOUT); + /* Set MPLL */ writel(MPLL_CON1_VAL, &clk->mpll_con1); val = set_pll(0xc8, 0x3, 0x1); diff --git a/src/cpu/samsung/exynos5420/setup.h b/src/cpu/samsung/exynos5420/setup.h index e89ed8e..c2f69d2 100644 --- a/src/cpu/samsung/exynos5420/setup.h +++ b/src/cpu/samsung/exynos5420/setup.h @@ -45,6 +45,9 @@ struct exynos5_phy_control; #define TZPC8_BASE 0x10180000 #define TZPC9_BASE 0x10190000
+#define APLL_FOUT (1 << 0) +#define KPLL_FOUT (1 << 0) + /* APLL_CON1 */ #define APLL_CON1_VAL (0x0020f300)