[PATCH 2/6 v7] clk, highbank: Prevent glitches in non-bypass reset mode

From: Mark Langsdorf
Date: Tue Dec 04 2012 - 09:33:56 EST


The highbank clock will glitch with the current code if the
clock rate is reset without relocking the PLL. Program the PLL
correctly to prevent glitches.

Signed-off-by: Mark Langsdorf <mark.langsdorf@xxxxxxxxxxx>
Signed-off-by: Rob Herring <rob.herring@xxxxxxxxxxx>
Acked-by: Mike Turquette <mturquette@xxxxxxxxxx>
---
Changes from v6
None.
Changes from v5
Added Mike Turquette's ack.
Changes from v4
None.
Changes from v3
Changelog text and patch name now correspond to the actual patch.
was clk, highbank: remove non-bypass reset mode.
Changes from v2
None.
Changes from v1:
Removed erroneous reformating.

drivers/clk/clk-highbank.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/clk/clk-highbank.c b/drivers/clk/clk-highbank.c
index 52fecad..3a0b723 100644
--- a/drivers/clk/clk-highbank.c
+++ b/drivers/clk/clk-highbank.c
@@ -182,8 +182,10 @@ static int clk_pll_set_rate(struct clk_hw *hwclk, unsigned long rate,
reg |= HB_PLL_EXT_ENA;
reg &= ~HB_PLL_EXT_BYPASS;
} else {
+ writel(reg | HB_PLL_EXT_BYPASS, hbclk->reg);
reg &= ~HB_PLL_DIVQ_MASK;
reg |= divq << HB_PLL_DIVQ_SHIFT;
+ writel(reg | HB_PLL_EXT_BYPASS, hbclk->reg);
}
writel(reg, hbclk->reg);

--
1.7.11.7

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