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pxa: fix memory coherency problem after relocation

On the xscale, the icache must be invalidated and the write buffers drained
after writing code over the data bus, even if the caches are disabled.  Tested
on the pxa270.

Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
Mike Dunn 12 years ago
parent
commit
9dc8fef258
1 changed files with 9 additions and 0 deletions
  1. 9 0
      arch/arm/lib/relocate.S

+ 9 - 0
arch/arm/lib/relocate.S

@@ -70,6 +70,15 @@ fixnext:
 
 relocate_done:
 
+#ifdef __XSCALE__
+	/*
+	 * On xscale, icache must be invalidated and write buffers drained,
+	 * even with cache disabled - 4.2.7 of xscale core developer's manual
+	 */
+	mcr	p15, 0, r0, c7, c7, 0	/* invalidate icache */
+	mcr	p15, 0, r0, c7, c10, 4	/* drain write buffer */
+#endif
+
 	/* ARMv4- don't know bx lr but the assembler fails to see that */
 
 #ifdef __ARM_ARCH_4__