[PATCH 1/3] imx6: clock: improve calculations to get the PLL video rate
Dario Binacchi
dario.binacchi at amarulasolutions.com
Sat Feb 25 09:38:19 CET 2023
During some tests to check the pixel clock rate in the transition from
U-Boot to the Linux kernel, I noticed that with the same configuration
of the registers the debug messages reported different rates.
The same Linux kernel calculations are now used to get the PLL video
rate.
Signed-off-by: Dario Binacchi <dario.binacchi at amarulasolutions.com>
---
arch/arm/mach-imx/mx6/clock.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/arch/arm/mach-imx/mx6/clock.c b/arch/arm/mach-imx/mx6/clock.c
index cb9d629be408..17d8dcd5c841 100644
--- a/arch/arm/mach-imx/mx6/clock.c
+++ b/arch/arm/mach-imx/mx6/clock.c
@@ -213,6 +213,7 @@ int enable_spi_clk(unsigned char enable, unsigned spi_num)
static u32 decode_pll(enum pll_clocks pll, u32 infreq)
{
u32 div, test_div, pll_num, pll_denom;
+ u64 temp64;
switch (pll) {
case PLL_SYS:
@@ -272,7 +273,10 @@ static u32 decode_pll(enum pll_clocks pll, u32 infreq)
}
test_div = 1 << (2 - test_div);
- return infreq * (div + pll_num / pll_denom) / test_div;
+ temp64 = (u64)infreq;
+ temp64 *= pll_num;
+ do_div(temp64, pll_denom);
+ return infreq * div + (unsigned long)temp64;
default:
return 0;
}
--
2.32.0
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