| Message ID | 20141216150338.D4F0A1A5E0A@localhost.localdomain (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Scott Wood |
| Headers | show |
On Tue, 2014-12-16 at 16:03 +0100, Christophe Leroy wrote: > All accessed to PGD entries are done via 0(r11). > By using lower part of swapper_pg_dir as load index to r11, we can remove the > ori instruction. > > Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Nice :) Acked-by: Joakim Tjernlund <joakim.tjernlund@transmode.se> > > --- > arch/powerpc/kernel/head_8xx.S | 22 ++++++++++------------ > 1 file changed, 10 insertions(+), 12 deletions(-) > > diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S > index ae05f28..aa45225 100644 > --- a/arch/powerpc/kernel/head_8xx.S > +++ b/arch/powerpc/kernel/head_8xx.S > @@ -322,13 +322,12 @@ InstructionTLBMiss: > mfspr r11, SPRN_M_TW/* Get level 1 table base address */ > #ifdef CONFIG_MODULES > beq 3f > - lis r11, (swapper_pg_dir-PAGE_OFFSET)@h > - ori r11, r11, (swapper_pg_dir-PAGE_OFFSET)@l > + lis r11, (swapper_pg_dir-PAGE_OFFSET)@ha > 3: > #endif > /* Insert level 1 index */ > rlwimi r11, r10, 32 - ((PAGE_SHIFT - 2) << 1), (PAGE_SHIFT - 2) << 1, 29 > - lwz r11, 0(r11)/* Get the level 1 entry */ > + lwz r11, (swapper_pg_dir-PAGE_OFFSET)@l(r11)/* Get the level 1 entry */ > > /* Load the MI_TWC with the attributes for this "segment." */ > MTSPR_CPU6(SPRN_MI_TWC, r11, r3)/* Set segment attributes */ > @@ -376,12 +375,11 @@ DataStoreTLBMiss: > andis. r11, r10, 0x8000 > mfspr r11, SPRN_M_TW/* Get level 1 table base address */ > beq 3f > - lis r11, (swapper_pg_dir-PAGE_OFFSET)@h > - ori r11, r11, (swapper_pg_dir-PAGE_OFFSET)@l > + lis r11, (swapper_pg_dir-PAGE_OFFSET)@ha > 3: > /* Insert level 1 index */ > rlwimi r11, r10, 32 - ((PAGE_SHIFT - 2) << 1), (PAGE_SHIFT - 2) << 1, 29 > - lwz r11, 0(r11)/* Get the level 1 entry */ > + lwz r11, (swapper_pg_dir-PAGE_OFFSET)@l(r11)/* Get the level 1 entry */ > > /* We have a pte table, so load fetch the pte from the table. > */ > @@ -510,12 +508,11 @@ FixupDAR:/* Entry point for dcbx workaround. */ > mfspr r10, SPRN_SRR0 > andis. r11, r10, 0x8000/* Address >= 0x80000000 */ > mfspr r11, SPRN_M_TW/* Get level 1 table base address */ > - beq- 3f /* Branch if user space */ > - lis r11, (swapper_pg_dir-PAGE_OFFSET)@h > - ori r11, r11, (swapper_pg_dir-PAGE_OFFSET)@l > + beq 3f > + lis r11, (swapper_pg_dir-PAGE_OFFSET)@ha > /* Insert level 1 index */ > 3: rlwimi r11, r10, 32 - ((PAGE_SHIFT - 2) << 1), (PAGE_SHIFT - 2) << 1, 29 > - lwz r11, 0(r11)/* Get the level 1 entry */ > + lwz r11, (swapper_pg_dir-PAGE_OFFSET)@l(r11)/* Get the level 1 entry */ > rlwinm r11, r11,0,0,19/* Extract page descriptor page address */ > /* Insert level 2 index */ > rlwimi r11, r10, 32 - (PAGE_SHIFT - 2), 32 - PAGE_SHIFT, 29 > @@ -670,8 +667,7 @@ start_here: > * init's THREAD like the context switch code does, but this is > * easier......until someone changes init's static structures. > */ > - lis r6, swapper_pg_dir@h > - ori r6, r6, swapper_pg_dir@l > + lis r6, swapper_pg_dir@ha > tophys(r6,r6) > #ifdef CONFIG_8xx_CPU6 > lis r4, cpu6_errata_word@h > @@ -850,6 +846,8 @@ _GLOBAL(set_context) > stw r4, 0x4(r5) > #endif > > + li r5, (swapper_pg_dir-PAGE_OFFSET)@l > + sub r4, r4, r5 > #ifdef CONFIG_8xx_CPU6 > lis r6, cpu6_errata_word@h > ori r6, r6, cpu6_errata_word@l
> On Tue, 2014-12-16 at 16:03 +0100, Christophe Leroy wrote: > > All accessed to PGD entries are done via 0(r11). > > By using lower part of swapper_pg_dir as load index to r11, we can remove the > > ori instruction. > > > > Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> > > Nice :) > Acked-by: Joakim Tjernlund <joakim.tjernlund@transmode.se> > > > > > --- > > arch/powerpc/kernel/head_8xx.S | 22 ++++++++++------------ > > 1 file changed, 10 insertions(+), 12 deletions(-) > > > > diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S > > index ae05f28..aa45225 100644 > > --- a/arch/powerpc/kernel/head_8xx.S > > +++ b/arch/powerpc/kernel/head_8xx.S > > @@ -322,13 +322,12 @@ InstructionTLBMiss: > > mfspr r11, SPRN_M_TW/* Get level 1 table base address */ > > #ifdef CONFIG_MODULES > > beq 3f > > - lis r11, (swapper_pg_dir-PAGE_OFFSET)@h > > - ori r11, r11, (swapper_pg_dir-PAGE_OFFSET)@l > > + lis r11, (swapper_pg_dir-PAGE_OFFSET)@ha > > 3: > > #endif > > /* Insert level 1 index */ > > rlwimi r11, r10, 32 - ((PAGE_SHIFT - 2) << 1), (PAGE_SHIFT - 2) << 1, 29 > > - lwz r11, 0(r11)/* Get the level 1 entry */ > > + lwz r11, (swapper_pg_dir-PAGE_OFFSET)@l(r11)/* Get the level 1 entry */ > > On the face of it that fragment doesn't look right when CONFIG_MODULES is undefined. David
Le 06/01/2015 13:08, David Laight a écrit : >> On Tue, 2014-12-16 at 16:03 +0100, Christophe Leroy wrote: >>> All accessed to PGD entries are done via 0(r11). >>> By using lower part of swapper_pg_dir as load index to r11, we can remove the >>> ori instruction. >>> >>> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> >> Nice :) >> Acked-by: Joakim Tjernlund <joakim.tjernlund@transmode.se> >> >>> --- >>> arch/powerpc/kernel/head_8xx.S | 22 ++++++++++------------ >>> 1 file changed, 10 insertions(+), 12 deletions(-) >>> >>> diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S >>> index ae05f28..aa45225 100644 >>> --- a/arch/powerpc/kernel/head_8xx.S >>> +++ b/arch/powerpc/kernel/head_8xx.S >>> @@ -322,13 +322,12 @@ InstructionTLBMiss: >>> mfspr r11, SPRN_M_TW/* Get level 1 table base address */ >>> #ifdef CONFIG_MODULES >>> beq 3f >>> - lis r11, (swapper_pg_dir-PAGE_OFFSET)@h >>> - ori r11, r11, (swapper_pg_dir-PAGE_OFFSET)@l >>> + lis r11, (swapper_pg_dir-PAGE_OFFSET)@ha >>> 3: >>> #endif >>> /* Insert level 1 index */ >>> rlwimi r11, r10, 32 - ((PAGE_SHIFT - 2) << 1), (PAGE_SHIFT - 2) << 1, 29 >>> - lwz r11, 0(r11)/* Get the level 1 entry */ >>> + lwz r11, (swapper_pg_dir-PAGE_OFFSET)@l(r11)/* Get the level 1 entry */ >>> > On the face of it that fragment doesn't look right when CONFIG_MODULES is undefined. > > David > I'm not sure I understand what you mean. The other part of the patch adds the following: + li r5, (swapper_pg_dir-PAGE_OFFSET)@l + sub r4, r4, r5 r4 is the value put into SPRN_M_TW, so I don't see what may be wrong. Christophe
From: leroy christophe > Le 06/01/2015 13:08, David Laight a écrit : > >> On Tue, 2014-12-16 at 16:03 +0100, Christophe Leroy wrote: > >>> All accessed to PGD entries are done via 0(r11). > >>> By using lower part of swapper_pg_dir as load index to r11, we can remove the > >>> ori instruction. > >>> > >>> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> > >> Nice :) > >> Acked-by: Joakim Tjernlund <joakim.tjernlund@transmode.se> > >> > >>> --- > >>> arch/powerpc/kernel/head_8xx.S | 22 ++++++++++------------ > >>> 1 file changed, 10 insertions(+), 12 deletions(-) > >>> > >>> diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S > >>> index ae05f28..aa45225 100644 > >>> --- a/arch/powerpc/kernel/head_8xx.S > >>> +++ b/arch/powerpc/kernel/head_8xx.S > >>> @@ -322,13 +322,12 @@ InstructionTLBMiss: > >>> mfspr r11, SPRN_M_TW/* Get level 1 table base address */ > >>> #ifdef CONFIG_MODULES > >>> beq 3f > >>> - lis r11, (swapper_pg_dir-PAGE_OFFSET)@h > >>> - ori r11, r11, (swapper_pg_dir-PAGE_OFFSET)@l > >>> + lis r11, (swapper_pg_dir-PAGE_OFFSET)@ha > >>> 3: > >>> #endif > >>> /* Insert level 1 index */ > >>> rlwimi r11, r10, 32 - ((PAGE_SHIFT - 2) << 1), (PAGE_SHIFT - 2) << 1, 29 > >>> - lwz r11, 0(r11)/* Get the level 1 entry */ > >>> + lwz r11, (swapper_pg_dir-PAGE_OFFSET)@l(r11)/* Get the level 1 entry */ > >>> > > On the face of it that fragment doesn't look right when CONFIG_MODULES is undefined. > > > > David > > > I'm not sure I understand what you mean. > > The other part of the patch adds the following: > + li r5, (swapper_pg_dir-PAGE_OFFSET)@l > + sub r4, r4, r5 > > r4 is the value put into SPRN_M_TW, so I don't see what may be wrong. Ok, but it is completely non-obvious. You probably need to change some comments somewhere about what is held in SPRN_M_TW - since it is no longer the L1 base address, but that value offset by some 'random' amount. David
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S index ae05f28..aa45225 100644 --- a/arch/powerpc/kernel/head_8xx.S +++ b/arch/powerpc/kernel/head_8xx.S @@ -322,13 +322,12 @@ InstructionTLBMiss: mfspr r11, SPRN_M_TW /* Get level 1 table base address */ #ifdef CONFIG_MODULES beq 3f - lis r11, (swapper_pg_dir-PAGE_OFFSET)@h - ori r11, r11, (swapper_pg_dir-PAGE_OFFSET)@l + lis r11, (swapper_pg_dir-PAGE_OFFSET)@ha 3: #endif /* Insert level 1 index */ rlwimi r11, r10, 32 - ((PAGE_SHIFT - 2) << 1), (PAGE_SHIFT - 2) << 1, 29 - lwz r11, 0(r11) /* Get the level 1 entry */ + lwz r11, (swapper_pg_dir-PAGE_OFFSET)@l(r11) /* Get the level 1 entry */ /* Load the MI_TWC with the attributes for this "segment." */ MTSPR_CPU6(SPRN_MI_TWC, r11, r3) /* Set segment attributes */ @@ -376,12 +375,11 @@ DataStoreTLBMiss: andis. r11, r10, 0x8000 mfspr r11, SPRN_M_TW /* Get level 1 table base address */ beq 3f - lis r11, (swapper_pg_dir-PAGE_OFFSET)@h - ori r11, r11, (swapper_pg_dir-PAGE_OFFSET)@l + lis r11, (swapper_pg_dir-PAGE_OFFSET)@ha 3: /* Insert level 1 index */ rlwimi r11, r10, 32 - ((PAGE_SHIFT - 2) << 1), (PAGE_SHIFT - 2) << 1, 29 - lwz r11, 0(r11) /* Get the level 1 entry */ + lwz r11, (swapper_pg_dir-PAGE_OFFSET)@l(r11) /* Get the level 1 entry */ /* We have a pte table, so load fetch the pte from the table. */ @@ -510,12 +508,11 @@ FixupDAR:/* Entry point for dcbx workaround. */ mfspr r10, SPRN_SRR0 andis. r11, r10, 0x8000 /* Address >= 0x80000000 */ mfspr r11, SPRN_M_TW /* Get level 1 table base address */ - beq- 3f /* Branch if user space */ - lis r11, (swapper_pg_dir-PAGE_OFFSET)@h - ori r11, r11, (swapper_pg_dir-PAGE_OFFSET)@l + beq 3f + lis r11, (swapper_pg_dir-PAGE_OFFSET)@ha /* Insert level 1 index */ 3: rlwimi r11, r10, 32 - ((PAGE_SHIFT - 2) << 1), (PAGE_SHIFT - 2) << 1, 29 - lwz r11, 0(r11) /* Get the level 1 entry */ + lwz r11, (swapper_pg_dir-PAGE_OFFSET)@l(r11) /* Get the level 1 entry */ rlwinm r11, r11,0,0,19 /* Extract page descriptor page address */ /* Insert level 2 index */ rlwimi r11, r10, 32 - (PAGE_SHIFT - 2), 32 - PAGE_SHIFT, 29 @@ -670,8 +667,7 @@ start_here: * init's THREAD like the context switch code does, but this is * easier......until someone changes init's static structures. */ - lis r6, swapper_pg_dir@h - ori r6, r6, swapper_pg_dir@l + lis r6, swapper_pg_dir@ha tophys(r6,r6) #ifdef CONFIG_8xx_CPU6 lis r4, cpu6_errata_word@h @@ -850,6 +846,8 @@ _GLOBAL(set_context) stw r4, 0x4(r5) #endif + li r5, (swapper_pg_dir-PAGE_OFFSET)@l + sub r4, r4, r5 #ifdef CONFIG_8xx_CPU6 lis r6, cpu6_errata_word@h ori r6, r6, cpu6_errata_word@l
All accessed to PGD entries are done via 0(r11). By using lower part of swapper_pg_dir as load index to r11, we can remove the ori instruction. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> --- arch/powerpc/kernel/head_8xx.S | 22 ++++++++++------------ 1 file changed, 10 insertions(+), 12 deletions(-)