From: Weijie Gao <hackpascal@xxxxxxxxx> According to the AR7242 datasheet section 2.8, AR724X CPUs use a 40MHz input clock as the REF_CLK instead of 5MHz. The correct CPU PLL calculation procedure is as follows: CPU_PLL = (FB * REF_CLK) / REF_DIV / 2. This patch is compatible with the current calculation procedure with default FB and REF_DIV values. Tested on AR7240, AR7241 and AR7242. Signed-off-by: Weijie Gao <hackpascal@xxxxxxxxx> Signed-off-by: Alban Bedel <albeu@xxxxxxx> [albeu@xxxxxxx: Fixed the commit log message] Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx> Cc: linux-mips@xxxxxxxxxxxxxx --- arch/mips/ath79/clock.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/mips/ath79/clock.c b/arch/mips/ath79/clock.c index eb5117c..ed28465 100644 --- a/arch/mips/ath79/clock.c +++ b/arch/mips/ath79/clock.c @@ -26,7 +26,7 @@ #include "common.h" #define AR71XX_BASE_FREQ 40000000 -#define AR724X_BASE_FREQ 5000000 +#define AR724X_BASE_FREQ 40000000 #define AR913X_BASE_FREQ 5000000 static struct clk *clks[3]; @@ -103,8 +103,8 @@ static void __init ar724x_clocks_init(void) div = ((pll >> AR724X_PLL_FB_SHIFT) & AR724X_PLL_FB_MASK); freq = div * ref_rate; - div = ((pll >> AR724X_PLL_REF_DIV_SHIFT) & AR724X_PLL_REF_DIV_MASK); - freq *= div; + div = ((pll >> AR724X_PLL_REF_DIV_SHIFT) & AR724X_PLL_REF_DIV_MASK) * 2; + freq /= div; cpu_rate = freq; -- 2.7.0
