[PATCH] powerpc/mm: Remove long disabled SLB code
Michael Ellerman
mpe at ellerman.id.au
Wed Mar 16 21:56:20 AEDT 2016
We have a bunch of SLB related code in the tree which is there to handle
dynamic VSIDs - but currently it's all disabled at compile time. The
comments say "Keep that around for when we re-implement dynamic VSIDs".
But that was over 10 years ago (commit 3c726f8dee6f ("[PATCH] ppc64:
support 64k pages")). The chance that it would still work unchanged is
minimal, and in the meantime it's confusing to folks browsing/grepping
the code. If we ever want to re-instate it, it's in the git history.
Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
---
arch/powerpc/kernel/exceptions-64s.S | 102 -----------------------------------
arch/powerpc/mm/slb.c | 1 -
arch/powerpc/mm/slb_low.S | 50 -----------------
3 files changed, 153 deletions(-)
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index 7716cebf4b8e..e0e1ff463556 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -209,11 +209,6 @@ data_access_slb_pSeries:
EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST, 0x380)
std r3,PACA_EXSLB+EX_R3(r13)
mfspr r3,SPRN_DAR
-#ifdef __DISABLED__
- /* Keep that around for when we re-implement dynamic VSIDs */
- cmpdi r3,0
- bge slb_miss_user_pseries
-#endif /* __DISABLED__ */
mfspr r12,SPRN_SRR1
#ifndef CONFIG_RELOCATABLE
b slb_miss_realmode
@@ -240,11 +235,6 @@ instruction_access_slb_pSeries:
EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST, 0x480)
std r3,PACA_EXSLB+EX_R3(r13)
mfspr r3,SPRN_SRR0 /* SRR0 is faulting address */
-#ifdef __DISABLED__
- /* Keep that around for when we re-implement dynamic VSIDs */
- cmpdi r3,0
- bge slb_miss_user_pseries
-#endif /* __DISABLED__ */
mfspr r12,SPRN_SRR1
#ifndef CONFIG_RELOCATABLE
b slb_miss_realmode
@@ -709,34 +699,6 @@ system_reset_fwnmi:
#endif /* CONFIG_PPC_PSERIES */
-#ifdef __DISABLED__
-/*
- * This is used for when the SLB miss handler has to go virtual,
- * which doesn't happen for now anymore but will once we re-implement
- * dynamic VSIDs for shared page tables
- */
-slb_miss_user_pseries:
- std r10,PACA_EXGEN+EX_R10(r13)
- std r11,PACA_EXGEN+EX_R11(r13)
- std r12,PACA_EXGEN+EX_R12(r13)
- GET_SCRATCH0(r10)
- ld r11,PACA_EXSLB+EX_R9(r13)
- ld r12,PACA_EXSLB+EX_R3(r13)
- std r10,PACA_EXGEN+EX_R13(r13)
- std r11,PACA_EXGEN+EX_R9(r13)
- std r12,PACA_EXGEN+EX_R3(r13)
- clrrdi r12,r13,32
- mfmsr r10
- mfspr r11,SRR0 /* save SRR0 */
- ori r12,r12,slb_miss_user_common at l /* virt addr of handler */
- ori r10,r10,MSR_IR|MSR_DR|MSR_RI
- mtspr SRR0,r12
- mfspr r12,SRR1 /* and SRR1 */
- mtspr SRR1,r10
- rfid
- b . /* prevent spec. execution */
-#endif /* __DISABLED__ */
-
#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
kvmppc_skip_interrupt:
/*
@@ -1012,70 +974,6 @@ instruction_access_common:
STD_EXCEPTION_COMMON(0xe20, h_instr_storage, unknown_exception)
-/*
- * Here is the common SLB miss user that is used when going to virtual
- * mode for SLB misses, that is currently not used
- */
-#ifdef __DISABLED__
- .align 7
- .globl slb_miss_user_common
-slb_miss_user_common:
- mflr r10
- std r3,PACA_EXGEN+EX_DAR(r13)
- stw r9,PACA_EXGEN+EX_CCR(r13)
- std r10,PACA_EXGEN+EX_LR(r13)
- std r11,PACA_EXGEN+EX_SRR0(r13)
- bl slb_allocate_user
-
- ld r10,PACA_EXGEN+EX_LR(r13)
- ld r3,PACA_EXGEN+EX_R3(r13)
- lwz r9,PACA_EXGEN+EX_CCR(r13)
- ld r11,PACA_EXGEN+EX_SRR0(r13)
- mtlr r10
- beq- slb_miss_fault
-
- andi. r10,r12,MSR_RI /* check for unrecoverable exception */
- beq- unrecov_user_slb
- mfmsr r10
-
-.machine push
-.machine "power4"
- mtcrf 0x80,r9
-.machine pop
-
- clrrdi r10,r10,2 /* clear RI before setting SRR0/1 */
- mtmsrd r10,1
-
- mtspr SRR0,r11
- mtspr SRR1,r12
-
- ld r9,PACA_EXGEN+EX_R9(r13)
- ld r10,PACA_EXGEN+EX_R10(r13)
- ld r11,PACA_EXGEN+EX_R11(r13)
- ld r12,PACA_EXGEN+EX_R12(r13)
- ld r13,PACA_EXGEN+EX_R13(r13)
- rfid
- b .
-
-slb_miss_fault:
- EXCEPTION_PROLOG_COMMON(0x380, PACA_EXGEN)
- ld r4,PACA_EXGEN+EX_DAR(r13)
- li r5,0
- std r4,_DAR(r1)
- std r5,_DSISR(r1)
- b handle_page_fault
-
-unrecov_user_slb:
- EXCEPTION_PROLOG_COMMON(0x4200, PACA_EXGEN)
- RECONCILE_IRQ_STATE(r10, r11)
- bl save_nvgprs
-1: addi r3,r1,STACK_FRAME_OVERHEAD
- bl unrecoverable_exception
- b 1b
-
-#endif /* __DISABLED__ */
-
-
/*
* Machine check is different because we use a different
* save area: PACA_EXMC instead of PACA_EXGEN.
diff --git a/arch/powerpc/mm/slb.c b/arch/powerpc/mm/slb.c
index 825b6873391f..48fc28bab544 100644
--- a/arch/powerpc/mm/slb.c
+++ b/arch/powerpc/mm/slb.c
@@ -32,7 +32,6 @@ enum slb_index {
};
extern void slb_allocate_realmode(unsigned long ea);
-extern void slb_allocate_user(unsigned long ea);
static void slb_allocate(unsigned long ea)
{
diff --git a/arch/powerpc/mm/slb_low.S b/arch/powerpc/mm/slb_low.S
index 736d18b3cefd..d3374004d20d 100644
--- a/arch/powerpc/mm/slb_low.S
+++ b/arch/powerpc/mm/slb_low.S
@@ -179,56 +179,6 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_1T_SEGMENT)
li r11,SLB_VSID_USER /* flags don't much matter */
b slb_finish_load
-#ifdef __DISABLED__
-
-/* void slb_allocate_user(unsigned long ea);
- *
- * Create an SLB entry for the given EA (user or kernel).
- * r3 = faulting address, r13 = PACA
- * r9, r10, r11 are clobbered by this function
- * No other registers are examined or changed.
- *
- * It is called with translation enabled in order to be able to walk the
- * page tables. This is not currently used.
- */
-_GLOBAL(slb_allocate_user)
- /* r3 = faulting address */
- srdi r10,r3,28 /* get esid */
-
- crset 4*cr7+lt /* set "user" flag for later */
-
- /* check if we fit in the range covered by the pagetables*/
- srdi. r9,r3,PGTABLE_EADDR_SIZE
- crnot 4*cr0+eq,4*cr0+eq
- beqlr
-
- /* now we need to get to the page tables in order to get the page
- * size encoding from the PMD. In the future, we'll be able to deal
- * with 1T segments too by getting the encoding from the PGD instead
- */
- ld r9,PACAPGDIR(r13)
- cmpldi cr0,r9,0
- beqlr
- rlwinm r11,r10,8,25,28
- ldx r9,r9,r11 /* get pgd_t */
- cmpldi cr0,r9,0
- beqlr
- rlwinm r11,r10,3,17,28
- ldx r9,r9,r11 /* get pmd_t */
- cmpldi cr0,r9,0
- beqlr
-
- /* build vsid flags */
- andi. r11,r9,SLB_VSID_LLP
- ori r11,r11,SLB_VSID_USER
-
- /* get context to calculate proto-VSID */
- ld r9,PACACONTEXTID(r13)
- /* fall through slb_finish_load */
-
-#endif /* __DISABLED__ */
-
-
/*
* Finish loading of an SLB entry and return
*
--
2.5.0
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