From: Weijie Gao <[email protected]>

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 <[email protected]>
Signed-off-by: Alban Bedel <[email protected]>
[[email protected]: Fixed the commit log message]
---
 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;
 
-- 
2.0.0

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