[U-Boot-Users] [PATCH 4/5][RESEND] CSB637 - set asynchronous clock mode

[Anders Larsen]

Hi,

the patch below selects AT91RM9200 asynchronous clock mode
which improves the execution speed by a factor of ~4.

Cheers
 Anders

Signed-off-by: Anders Larsen <alarsen at rea.de>

CHANGELOG:
  Patch by Anders Larsen <alarsen at rea.de>, 2005-05-03
  Set AT91RM9200 asynchronous clocking mode

---

 cpu/arm920t/at91rm9200/lowlevel_init.S |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/cpu/arm920t/at91rm9200/lowlevel_init.S b/cpu/arm920t/at91rm9200/lowlevel_init.S
--- a/cpu/arm920t/at91rm9200/lowlevel_init.S
+++ b/cpu/arm920t/at91rm9200/lowlevel_init.S
@@ -123,6 +123,11 @@ LoopOsc:
 	cmp	r2, r0
 	bne	2b
 
+	/* switch from FastBus to Asynchronous Clocking Mode */
+	mrc	p15, 0, r0, c1, c0, 0
+	orr	r0, r0, #0xC0000000	@ set bit 31 (iA) and 30 (nF)
+	mcr	p15, 0, r0, c1, c0, 0
+
 	/* everything is fine now */
 	mov	pc, lr