diff options
| author | Nicholas Piggin <npiggin@gmail.com> | 2017-05-21 15:15:42 +0200 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2017-06-20 14:18:25 +0200 |
| commit | d59afffdf04c66c09085160706297ec55833533c (patch) | |
| tree | 800f0c9726ea40a33cae0890ffac91176e204b1c /arch/powerpc/mm | |
| parent | powerpc/64s/idle: Run latch switch is done with MSR[EE]=0 (diff) | |
| download | linux-d59afffdf04c66c09085160706297ec55833533c.tar.xz linux-d59afffdf04c66c09085160706297ec55833533c.zip | |
powerpc/64s: Preserve r3 in slb_allocate_realmode()
One fewer registers clobbered by this function means the SLB miss
handler can save one fewer.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/mm')
| -rw-r--r-- | arch/powerpc/mm/slb_low.S | 24 |
1 files changed, 14 insertions, 10 deletions
diff --git a/arch/powerpc/mm/slb_low.S b/arch/powerpc/mm/slb_low.S index 1519617aab36..9869b44a04dc 100644 --- a/arch/powerpc/mm/slb_low.S +++ b/arch/powerpc/mm/slb_low.S @@ -70,6 +70,7 @@ ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_68_BIT_VA) * Create an SLB entry for the given EA (user or kernel). * r3 = faulting address, r13 = PACA * r9, r10, r11 are clobbered by this function + * r3 is preserved. * No other registers are examined or changed. */ _GLOBAL(slb_allocate_realmode) @@ -235,6 +236,9 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_1T_SEGMENT) * dont have any LRU information to help us choose a slot. */ + mr r9,r3 + + /* slb_finish_load_1T continues here. r9=EA with non-ESID bits clear */ 7: ld r10,PACASTABRR(r13) addi r10,r10,1 /* This gets soft patched on boot. */ @@ -249,10 +253,10 @@ slb_compare_rr_to_size: std r10,PACASTABRR(r13) 3: - rldimi r3,r10,0,36 /* r3= EA[0:35] | entry */ - oris r10,r3,SLB_ESID_V@h /* r3 |= SLB_ESID_V */ + rldimi r9,r10,0,36 /* r9 = EA[0:35] | entry */ + oris r10,r9,SLB_ESID_V@h /* r10 = r9 | SLB_ESID_V */ - /* r3 = ESID data, r11 = VSID data */ + /* r9 = ESID data, r11 = VSID data */ /* * No need for an isync before or after this slbmte. The exception @@ -265,21 +269,21 @@ slb_compare_rr_to_size: bgelr cr7 /* Update the slb cache */ - lhz r3,PACASLBCACHEPTR(r13) /* offset = paca->slb_cache_ptr */ - cmpldi r3,SLB_CACHE_ENTRIES + lhz r9,PACASLBCACHEPTR(r13) /* offset = paca->slb_cache_ptr */ + cmpldi r9,SLB_CACHE_ENTRIES bge 1f /* still room in the slb cache */ - sldi r11,r3,2 /* r11 = offset * sizeof(u32) */ + sldi r11,r9,2 /* r11 = offset * sizeof(u32) */ srdi r10,r10,28 /* get the 36 bits of the ESID */ add r11,r11,r13 /* r11 = (u32 *)paca + offset */ stw r10,PACASLBCACHE(r11) /* paca->slb_cache[offset] = esid */ - addi r3,r3,1 /* offset++ */ + addi r9,r9,1 /* offset++ */ b 2f 1: /* offset >= SLB_CACHE_ENTRIES */ - li r3,SLB_CACHE_ENTRIES+1 + li r9,SLB_CACHE_ENTRIES+1 2: - sth r3,PACASLBCACHEPTR(r13) /* paca->slb_cache_ptr = offset */ + sth r9,PACASLBCACHEPTR(r13) /* paca->slb_cache_ptr = offset */ crclr 4*cr0+eq /* set result to "success" */ blr @@ -301,7 +305,7 @@ slb_compare_rr_to_size: rldimi r11,r10,SLB_VSID_SSIZE_SHIFT,0 /* insert segment size */ /* r3 = EA, r11 = VSID data */ - clrrdi r3,r3,SID_SHIFT_1T /* clear out non-ESID bits */ + clrrdi r9,r3,SID_SHIFT_1T /* clear out non-ESID bits */ b 7b |