[U-Boot] [PATCH v3 2/4] at91: clock: remove chip macro for plla div2.
Josh Wu
josh.wu at atmel.com
Mon Mar 25 08:32:07 CET 2013
at91sam9x5, at91sam9n12, at91sam9g45/m10g45 has plla div2 bits. For other
at91 arm926ejs chips, this plla div2 bits (bit-12 in mckr) is reserved and
default value after reset is 0. So we can handle all the chip in a same way.
now we can simply remove the chip select macro.
This patch also changes the div2 code to a more readable format.
Signed-off-by: Josh Wu <josh.wu at atmel.com>
---
arch/arm/cpu/arm926ejs/at91/clock.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/arch/arm/cpu/arm926ejs/at91/clock.c b/arch/arm/cpu/arm926ejs/at91/clock.c
index f825388..b6fd2ef 100644
--- a/arch/arm/cpu/arm926ejs/at91/clock.c
+++ b/arch/arm/cpu/arm926ejs/at91/clock.c
@@ -155,11 +155,12 @@ int at91_clock_init(unsigned long main_clock)
* For now, assume this parentage won't change.
*/
mckr = readl(&pmc->mckr);
-#if defined(CONFIG_AT91SAM9G45) || defined(CONFIG_AT91SAM9M10G45) \
- || defined(CONFIG_AT91SAM9X5)
- /* plla divisor by 2 */
- gd->arch.plla_rate_hz /= (1 << ((mckr & 1 << 12) >> 12));
-#endif
+
+ /* plla divisor by 2, Only for AT91SAM9G45, 9M10G45, 9X5, 9N12 */
+ /* For other AT91 chip, the bit 12 of MCKR is reserved, default is 0 */
+ if (mckr & (1 << 12))
+ gd->arch.plla_rate_hz >>= 1;
+
gd->arch.mck_rate_hz = at91_css_to_rate(mckr & AT91_PMC_MCKR_CSS_MASK);
freq = gd->arch.mck_rate_hz;
--
1.7.9.5
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