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Commit 1f4c66e8 authored by Michael Ellerman's avatar Michael Ellerman
Browse files

powerpc/mm: Remove long disabled SLB code 



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 3c726f8d ("[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: default avatarMichael Ellerman <mpe@ellerman.id.au>
Acked-by: default avatarBalbir Singh <bsingharora@gmail.com>
parent f8a25db4

arch/powerpc/kernel/exceptions-64s.S

+0 −102
Original line number Diff line number Diff line
@@ -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@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.

arch/powerpc/mm/slb.c

+0 −1
Original line number Diff line number Diff line
@@ -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)

{

arch/powerpc/mm/slb_low.S

+0 −50
Original line number Diff line number Diff line
@@ -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

 *