| Message ID | 1407308589-21311-1-git-send-email-alistair@popple.id.au (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 97b3be1e9404f4c1645f3286428abd4d2052041e |
| Headers | show |
diff --git a/arch/powerpc/kernel/head_44x.S b/arch/powerpc/kernel/head_44x.S index c334f53..b5061ab 100644 --- a/arch/powerpc/kernel/head_44x.S +++ b/arch/powerpc/kernel/head_44x.S @@ -1210,10 +1210,12 @@ clear_utlb_entry: /* We configure icbi to invalidate 128 bytes at a time since the * current 32-bit kernel code isn't too happy with icache != dcache - * block size + * block size. We also disable the BTAC as this can cause errors + * in some circumstances (see IBM Erratum 47). */ mfspr r3,SPRN_CCR0 oris r3,r3,0x0020 + ori r3,r3,0x0040 mtspr SPRN_CCR0,r3 isync
This patch disables the branch target address CAM which under specific circumstances may cause the processor to skip execution of 1-4 instructions. This fixes IBM Erratum #47. Signed-off-by: Alistair Popple <alistair@popple.id.au> --- arch/powerpc/kernel/head_44x.S | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)