From patchwork Tue Sep 16 15:15:44 2008 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [v5,3/4] powerpc/fsl-booke: Fixup 64-bit PTE reading for SMP support Date: Tue, 16 Sep 2008 05:15:44 -0000 From: Kumar Gala X-Patchwork-Id: 321 Message-Id: <1221578145-29102-3-git-send-email-galak@kernel.crashing.org> To: linuxppc-dev@ozlabs.org We need to create a false data dependency to ensure the loads of the pte are done in the right order. Signed-off-by: Kumar Gala diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S index 3cb52fa..377e0c1 100644 --- a/arch/powerpc/kernel/head_fsl_booke.S +++ b/arch/powerpc/kernel/head_fsl_booke.S @@ -579,13 +579,19 @@ interrupt_base: FIND_PTE andc. r13,r13,r11 /* Check permission */ - bne 2f /* Bail if permission mismach */ #ifdef CONFIG_PTE_64BIT - lwz r13, 0(r12) +#ifdef CONFIG_SMP + subf r10,r11,r12 /* create false data dep */ + lwzx r13,r11,r10 /* Get upper pte bits */ +#else + lwz r13,0(r12) /* Get upper pte bits */ +#endif #endif - /* Jump to common tlb load */ + bne 2f /* Bail if permission/valid mismach */ + + /* Jump to common tlb load */ b finish_tlb_load 2: /* The bailout. Restore registers to pre-exception conditions @@ -640,10 +646,20 @@ interrupt_base: FIND_PTE andc. r13,r13,r11 /* Check permission */ + +#ifdef CONFIG_PTE_64BIT +#ifdef CONFIG_SMP + subf r10,r11,r12 /* create false data dep */ + lwzx r13,r11,r10 /* Get upper pte bits */ +#else + lwz r13,0(r12) /* Get upper pte bits */ +#endif +#endif + bne 2f /* Bail if permission mismach */ #ifdef CONFIG_PTE_64BIT - lwz r13, 0(r12) + lwz r13,0(r12) #endif /* Jump to common TLB load point */ @@ -702,7 +718,7 @@ interrupt_base: /* * Both the instruction and data TLB miss get to this * point to load the TLB. - * r10 - EA of fault + * r10 - available to use * r11 - TLB (info from Linux PTE) * r12 - available to use * r13 - upper bits of PTE (if PTE_64BIT) or available to use