4.14-stable patches

[thirdparty/kernel/stable-queue.git] / releases / 4.14.44 / clk-samsung-exynos5260-fix-pll-rates.patch

From foo@baz Thu May 24 11:09:34 CEST 2018
From: Andrzej Hajda <a.hajda@samsung.com>
Date: Fri, 16 Feb 2018 15:57:50 +0100
Subject: clk: samsung: exynos5260: Fix PLL rates

From: Andrzej Hajda <a.hajda@samsung.com>

[ Upstream commit cdb68fbd4e7962be742c4f29475220c5bf28d8a5 ]

Rates declared in PLL rate tables should match exactly rates calculated from
the PLL coefficients. If that is not the case, rate of the PLL's child clock
might be set not as expected. For instance, if in the PLL rates table we have
a 393216000 Hz entry and the real value as returned by the PLL's recalc_rate
callback is 393216003, after setting PLL's clk rate to 393216000 clk_get_rate
will return 393216003. If we now attempt to set rate of a PLL's child divider
clock to 393216000/2 its rate will be 131072001, rather than 196608000.
That is, the divider will be set to 3 instead of 2, because 393216003/2 is
greater than 196608000.

To fix this issue declared rates are changed to exactly match rates generated
by the PLL, as calculated from the P, M, S, K coefficients.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Acked-by: Tomasz Figa <tomasz.figa@gmail.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/clk/samsung/clk-exynos5260.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/clk/samsung/clk-exynos5260.c
+++ b/drivers/clk/samsung/clk-exynos5260.c
@@ -65,7 +65,7 @@ static const struct samsung_pll_rate_tab
 	PLL_36XX_RATE(480000000, 160, 2, 2, 0),
 	PLL_36XX_RATE(432000000, 144, 2, 2, 0),
 	PLL_36XX_RATE(400000000, 200, 3, 2, 0),
-	PLL_36XX_RATE(394073130, 459, 7, 2, 49282),
+	PLL_36XX_RATE(394073128, 459, 7, 2, 49282),
 	PLL_36XX_RATE(333000000, 111, 2, 2, 0),
 	PLL_36XX_RATE(300000000, 100, 2, 2, 0),
 	PLL_36XX_RATE(266000000, 266, 3, 3, 0),