diff options
Diffstat (limited to 'arch/ppc/kernel/l2cr.S')
| -rw-r--r-- | arch/ppc/kernel/l2cr.S | 31 |
1 files changed, 30 insertions, 1 deletions
diff --git a/arch/ppc/kernel/l2cr.S b/arch/ppc/kernel/l2cr.S index c3944104826..861115249b3 100644 --- a/arch/ppc/kernel/l2cr.S +++ b/arch/ppc/kernel/l2cr.S @@ -156,6 +156,26 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC) The bit moved on the 7450..... ****/ +BEGIN_FTR_SECTION + /* Disable L2 prefetch on some 745x and try to ensure + * L2 prefetch engines are idle. As explained by errata + * text, we can't be sure they are, we just hope very hard + * that well be enough (sic !). At least I noticed Apple + * doesn't even bother doing the dcbf's here... + */ + mfspr r4,SPRN_MSSCR0 + rlwinm r4,r4,0,0,29 + sync + mtspr SPRN_MSSCR0,r4 + sync + isync + lis r4,KERNELBASE@h + dcbf 0,r4 + dcbf 0,r4 + dcbf 0,r4 + dcbf 0,r4 +END_FTR_SECTION_IFSET(CPU_FTR_SPEC7450) + /* TODO: use HW flush assist when available */ lis r4,0x0002 @@ -230,7 +250,16 @@ END_FTR_SECTION_IFSET(CPU_FTR_SPEC7450) oris r3,r3,0x8000 mtspr SPRN_L2CR,r3 sync - + + /* Enable L2 HW prefetch on 744x/745x */ +BEGIN_FTR_SECTION + mfspr r3,SPRN_MSSCR0 + ori r3,r3,3 + sync + mtspr SPRN_MSSCR0,r3 + sync + isync +END_FTR_SECTION_IFSET(CPU_FTR_SPEC7450) 4: /* Restore HID0[DPM] to whatever it was before */ |