[PATCH v2] ARM: map ATAGs when not in first 1MB of RAM
Rob Herring
robherring2 at gmail.com
Sat Jan 29 01:00:46 EST 2011
From: Rob Herring <rob.herring at calxeda.com>
If ATAGs or DTB pointer is not within first 1MB of RAM, then the boot params
will not be mapped early enough, so map the 1MB region that r2 points to. Only
map the first 1MB when r2 is 0.
Some assembly improvements from Nicolas Pitre.
Signed-off-by: Rob Herring <rob.herring at calxeda.com>
---
Applies to Russell's p2v branch
arch/arm/kernel/head.S | 14 ++++++++++----
1 files changed, 10 insertions(+), 4 deletions(-)
diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
index 17a97b5..d4efa71 100644
--- a/arch/arm/kernel/head.S
+++ b/arch/arm/kernel/head.S
@@ -206,11 +206,17 @@ __create_page_tables:
#endif
/*
- * Then map first 1MB of ram in case it contains our boot params.
+ * Then map boot params address in r2 or
+ * the first 1MB of ram if boot params address is not specified.
*/
- add r0, r4, #PAGE_OFFSET >> 18
- orr r6, r7, r8
- str r6, [r0]
+ mov r0, r2, lsr #20
+ movs r0, r0, lsl #20
+ moveq r0, r8
+ sub r3, r0, r8
+ add r3, r3, #PAGE_OFFSET
+ add r3, r4, r3, lsr #18
+ orr r6, r7, r0
+ str r6, [r3]
#ifdef CONFIG_DEBUG_LL
#ifndef CONFIG_DEBUG_ICEDCC
--
1.7.1
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