[U-Boot] [PATCH] arm: exynos: fix clock calculation

Minkyu Kang mk7.kang at samsung.com
Fri Jul 5 12:13:42 CEST 2013


There are differnce with clock calcuation by cpu variations.
This patch will fix it according to user manual.

Signed-off-by: Minkyu Kang <mk7.kang at samsung.com>
Signed-off-by: Rajeshwari Shinde <rajeshwari.s at samsung.com>
---
 arch/arm/cpu/armv7/exynos/clock.c |   37 +++++++++++++++++++++++++++++++++----
 1 file changed, 33 insertions(+), 4 deletions(-)

diff --git a/arch/arm/cpu/armv7/exynos/clock.c b/arch/arm/cpu/armv7/exynos/clock.c
index e1c4246..da43373 100644
--- a/arch/arm/cpu/armv7/exynos/clock.c
+++ b/arch/arm/cpu/armv7/exynos/clock.c
@@ -85,6 +85,7 @@ static struct set_epll_con_val exynos5_epll_div[] = {
 static int exynos_get_pll_clk(int pllreg, unsigned int r, unsigned int k)
 {
 	unsigned long m, p, s = 0, mask, fout;
+	unsigned int div;
 	unsigned int freq;
 	/*
 	 * APLL_CON: MIDV [25:16]
@@ -113,11 +114,39 @@ static int exynos_get_pll_clk(int pllreg, unsigned int r, unsigned int k)
 		fout = (m + k / 65536) * (freq / (p * (1 << s)));
 	} else if (pllreg == VPLL) {
 		k = k & 0xfff;
-		/* FOUT = (MDIV + K / 1024) * FIN / (PDIV * 2^SDIV) */
-		fout = (m + k / 1024) * (freq / (p * (1 << s)));
+
+		/*
+		 * Exynos4210
+		 * FOUT = (MDIV + K / 1024) * FIN / (PDIV * 2^SDIV)
+		 *
+		 * Exynos4412
+		 * FOUT = (MDIV + K / 65535) * FIN / (PDIV * 2^SDIV)
+		 *
+		 * Exynos5250
+		 * FOUT = (MDIV + K / 65536) * FIN / (PDIV * 2^SDIV)
+		 */
+		if (proid_is_exynos4210())
+			div = 1024;
+		else if (proid_is_exynos4412())
+			div = 65535;
+		else if (proid_is_exynos5250())
+			div = 65536;
+		else
+			return 0;
+
+		fout = (m + k / div) * (freq / (p * (1 << s)));
 	} else {
-		/* FOUT = MDIV * FIN / (PDIV * 2^SDIV) */
-		fout = m * (freq / (p * (1 << s)));
+		/*
+		 * Exynos4210
+		 * FOUT = MDIV * FIN / (PDIV * 2^SDIV)
+		 *
+		 * Exynos4412 / Exynos5250
+		 * FOUT = MDIV * FIN / (PDIV * 2^(SDIV-1))
+		 */
+		if (proid_is_exynos4210())
+			fout = m * (freq / (p * (1 << s)));
+		else
+			fout = m * (freq / (p * (1 << (s - 1))));
 	}
 
 	return fout;
-- 
1.7.9.5

-- 
Thanks,
Minkyu Kang.


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