[PATCH v3 17/23] powerpc/8xx: rewrite flush_instruction_cache() in C

From: Christophe Leroy
Date: Tue Nov 17 2015 - 09:02:37 EST


On PPC8xx, flushing instruction cache is performed by writing
in register SPRN_IC_CST. This registers suffers CPU6 ERRATA.
The patch rewrites the fonction in C so that CPU6 ERRATA will
be handled transparently

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
---
v2: no change
v3: no change

arch/powerpc/kernel/misc_32.S | 10 ++++------
arch/powerpc/mm/8xx_mmu.c | 7 +++++++
2 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S
index ed3ab50..72fd7a7 100644
--- a/arch/powerpc/kernel/misc_32.S
+++ b/arch/powerpc/kernel/misc_32.S
@@ -296,12 +296,9 @@ _GLOBAL(real_writeb)
* Flush instruction cache.
* This is a no-op on the 601.
*/
+#ifndef CONFIG_PPC_8xx
_GLOBAL(flush_instruction_cache)
-#if defined(CONFIG_8xx)
- isync
- lis r5, IDC_INVALL@h
- mtspr SPRN_IC_CST, r5
-#elif defined(CONFIG_4xx)
+#if defined(CONFIG_4xx)
#ifdef CONFIG_403GCX
li r3, 512
mtctr r3
@@ -334,9 +331,10 @@ END_FTR_SECTION_IFSET(CPU_FTR_UNIFIED_ID_CACHE)
mfspr r3,SPRN_HID0
ori r3,r3,HID0_ICFI
mtspr SPRN_HID0,r3
-#endif /* CONFIG_8xx/4xx */
+#endif /* CONFIG_4xx */
isync
blr
+#endif /* CONFIG_PPC_8xx */

/*
* Write any modified data cache blocks out to memory
diff --git a/arch/powerpc/mm/8xx_mmu.c b/arch/powerpc/mm/8xx_mmu.c
index e6a23ad..3d3b5bf 100644
--- a/arch/powerpc/mm/8xx_mmu.c
+++ b/arch/powerpc/mm/8xx_mmu.c
@@ -181,3 +181,10 @@ void set_context(unsigned long id, pgd_t *pgd)
/* sync */
mb();
}
+
+void flush_instruction_cache(void)
+{
+ isync();
+ mtspr(SPRN_IC_CST, IDC_INVALL);
+ isync();
+}
--
2.1.0

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