From 5b30850bd6bda5188eedec60d364256617a87343 Mon Sep 17 00:00:00 2001 From: Sylwester Nawrocki Date: Fri, 21 Jul 2017 13:19:50 +0200 Subject: clk: samsung: exynos5420: The EPLL rate table corrections This patch fixes values of the EPLL K coefficient and changes the EPLL output frequency values to match exactly what is possible to achieve with given M, P, S, K coefficients. This allows to avoid rounding errors and unexpected frequency being set with clk_set_rate(), due to recalc_rate returning different values than the PLL rate specified in the exynos5420_epll_24mhz_tbl table. E.g. this prevents a case where two consecutive clk_set_rate() calls with same argument result in different PLL output frequency. The PLL output frequencies have been calculated with formula: f = fxtal * (M * 2^16 + K) / (P * 2^S) / 2^16 where fxtal = 24000000. Fixes: 9842452acd ("clk: samsung: exynos542x: Add EPLL rate table") Signed-off-by: Sylwester Nawrocki Signed-off-by: Stephen Boyd --- drivers/clk/samsung/clk-exynos5420.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) (limited to 'drivers/clk') diff --git a/drivers/clk/samsung/clk-exynos5420.c b/drivers/clk/samsung/clk-exynos5420.c index 0748a0b333c5..9a6476aa7d81 100644 --- a/drivers/clk/samsung/clk-exynos5420.c +++ b/drivers/clk/samsung/clk-exynos5420.c @@ -1283,16 +1283,16 @@ static const struct samsung_pll_rate_table exynos5420_pll2550x_24mhz_tbl[] __ini static const struct samsung_pll_rate_table exynos5420_epll_24mhz_tbl[] = { PLL_36XX_RATE(600000000U, 100, 2, 1, 0), PLL_36XX_RATE(400000000U, 200, 3, 2, 0), - PLL_36XX_RATE(393216000U, 197, 3, 2, 25690), - PLL_36XX_RATE(361267200U, 301, 5, 2, 3671), + PLL_36XX_RATE(393216003U, 197, 3, 2, -25690), + PLL_36XX_RATE(361267218U, 301, 5, 2, 3671), PLL_36XX_RATE(200000000U, 200, 3, 3, 0), - PLL_36XX_RATE(196608000U, 197, 3, 3, -25690), - PLL_36XX_RATE(180633600U, 301, 5, 3, 3671), - PLL_36XX_RATE(131072000U, 131, 3, 3, 4719), + PLL_36XX_RATE(196608001U, 197, 3, 3, -25690), + PLL_36XX_RATE(180633609U, 301, 5, 3, 3671), + PLL_36XX_RATE(131072006U, 131, 3, 3, 4719), PLL_36XX_RATE(100000000U, 200, 3, 4, 0), - PLL_36XX_RATE(65536000U, 131, 3, 4, 4719), - PLL_36XX_RATE(49152000U, 197, 3, 5, 25690), - PLL_36XX_RATE(32768000U, 131, 3, 5, 4719), + PLL_36XX_RATE( 65536003U, 131, 3, 4, 4719), + PLL_36XX_RATE( 49152000U, 197, 3, 5, -25690), + PLL_36XX_RATE( 32768001U, 131, 3, 5, 4719), }; static struct samsung_pll_clock exynos5x_plls[nr_plls] __initdata = { -- cgit v1.2.3