[PATCH v8 17/23] powerpc/8xx: rewrite flush_instruction_cache() in C

Christophe Leroy christophe.leroy at c-s.fr
Wed Feb 10 03:08:21 AEDT 2016


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 at c-s.fr>
---
v2: no change
v3: no change
v4: no change
v5: no change
v6: no change
v8: 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 be8edd6..7d1284f 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 at 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 b75c461..e2ce480 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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