| Message ID | 1263573697-17839-3-git-send-email-linuxppc-dev@ml.breakpoint.cc (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Kumar Gala |
| Headers | show |
On Jan 15, 2010, at 10:41 AM, Sebastian Andrzej Siewior wrote: > From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> > > Right now the setup code takes ESEL of the current mapping and puts the > temporary into ESEL (old_ESEL & 1 ) + 1 which is either one or two. > This is actually not required since all slots in TLB0 are invalid by now > and can be used. > This patch moved the temp mapping to TLB0, ESEL[0]. The invalidation of > TLB0 does not care about IPPROT so that part can go as well. > The benefit is that now the setup code may set every slot of TLB1 while > before that it was not allowed to touch ESEL one or two depending on the > old_ESEL. > > Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> > --- > arch/powerpc/kernel/head_fsl_booke.S | 20 +++++--------------- > 1 files changed, 5 insertions(+), 15 deletions(-) this is problematic, we can't assume that TLB0 is safe. It possible some other software is running on a second core and does a broadcast tlbivax which will wipe what's in TLB0. - k
* Kumar Gala | 2010-02-17 21:09:08 [-0600]: > >On Jan 15, 2010, at 10:41 AM, Sebastian Andrzej Siewior wrote: > >> From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> >> >> Right now the setup code takes ESEL of the current mapping and puts the >> temporary into ESEL (old_ESEL & 1 ) + 1 which is either one or two. >> This is actually not required since all slots in TLB0 are invalid by now >> and can be used. >> This patch moved the temp mapping to TLB0, ESEL[0]. The invalidation of >> TLB0 does not care about IPPROT so that part can go as well. >> The benefit is that now the setup code may set every slot of TLB1 while >> before that it was not allowed to touch ESEL one or two depending on the >> old_ESEL. >> >> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> >> --- >> arch/powerpc/kernel/head_fsl_booke.S | 20 +++++--------------- >> 1 files changed, 5 insertions(+), 15 deletions(-) > >this is problematic, we can't assume that TLB0 is safe. It possible some other software is running on a second core and does a broadcast tlbivax which will wipe what's in TLB0. Ah right SMP. So if CPU0 would wait until CPU1-X are up and kick them one by one could make it work but is not that pretty. So let me think of something. I will probably just skip the current mapping while making new ones for kexec. >- k Sebastian
diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S index 799ddbe..cc76952 100644 --- a/arch/powerpc/kernel/head_fsl_booke.S +++ b/arch/powerpc/kernel/head_fsl_booke.S @@ -165,8 +165,6 @@ skpinv: addi r6,r6,1 /* Increment */ TLBSYNC /* 3. Setup a temp mapping and jump to it */ - andi. r5, r3, 0x1 /* Find an entry not used and is non-zero */ - addi r5, r5, 0x1 lis r7,0x1000 /* Set MAS0(TLBSEL) = 1 */ rlwimi r7,r3,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r3) */ mtspr SPRN_MAS0,r7 @@ -194,12 +192,11 @@ skpinv: addi r6,r6,1 /* Increment */ ori r8,r25,(MAS3_SX|MAS3_SW|MAS3_SR) /* Just modify the entry ID and EPN for the temp mapping */ - lis r7,0x1000 /* Set MAS0(TLBSEL) = 1 */ - rlwimi r7,r5,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r5) */ + li r7, 0 /* Set MAS0(TLBSEL) = 0 | ESEL(0) */ mtspr SPRN_MAS0,r7 xori r6,r4,1 /* Setup TMP mapping in the other Address space */ slwi r6,r6,12 - oris r6,r6,(MAS1_VALID|MAS1_IPROT)@h + oris r6,r6,(MAS1_VALID)@h ori r6,r6,(MAS1_TSIZE(BOOK3E_PAGESZ_4K))@l mtspr SPRN_MAS1,r6 mfspr r6,SPRN_MAS2 @@ -281,16 +278,9 @@ skpinv: addi r6,r6,1 /* Increment */ rfi /* start execution out of TLB1[0] entry */ /* 8. Clear out the temp mapping */ -2: lis r7,0x1000 /* Set MAS0(TLBSEL) = 1 */ - rlwimi r7,r5,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r5) */ - mtspr SPRN_MAS0,r7 - tlbre - mfspr r8,SPRN_MAS1 - rlwinm r8,r8,0,2,0 /* clear IPROT */ - mtspr SPRN_MAS1,r8 - tlbwe - /* Invalidate TLB1 */ - li r9,0x0c +2: + /* Invalidate TLB0 */ + li r9,0x04 tlbivax 0,r9 TLBSYNC