Commit 99b22916 authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc/8xx: Enable CONFIG_VMAP_STACK 



This patch enables CONFIG_VMAP_STACK. For that, a few changes are
done in head_8xx.S.

Signed-off-by: default avatarChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/d7ba1e34e80898310d6a314cbebe48baa32894ef.1576916812.git.christophe.leroy@c-s.fr
parent d52668f6

arch/powerpc/kernel/head_8xx.S

+26 −6
Original line number Diff line number Diff line
@@ -127,7 +127,7 @@ instruction_counter: 
/* Machine check */

	. = 0x200

MachineCheck:

	EXCEPTION_PROLOG

	EXCEPTION_PROLOG handle_dar_dsisr=1

	save_dar_dsisr_on_stack r4, r5, r11

	li	r6, RPN_PATTERN

	mtspr	SPRN_DAR, r6	/* Tag DAR, to be used in DTLB Error */
@@ -140,7 +140,7 @@ MachineCheck: 
/* Alignment exception */

	. = 0x600

Alignment:

	EXCEPTION_PROLOG

	EXCEPTION_PROLOG handle_dar_dsisr=1

	save_dar_dsisr_on_stack r4, r5, r11

	li	r6, RPN_PATTERN

	mtspr	SPRN_DAR, r6	/* Tag DAR, to be used in DTLB Error */
@@ -462,20 +462,26 @@ InstructionTLBError: 
 */

	. = 0x1400

DataTLBError:

	EXCEPTION_PROLOG_0

	EXCEPTION_PROLOG_0 handle_dar_dsisr=1

	mfspr	r11, SPRN_DAR

	cmpwi	cr1, r11, RPN_PATTERN

	beq-	cr1, FixupDAR	/* must be a buggy dcbX, icbi insn. */

DARFixed:/* Return from dcbx instruction bug workaround */

#ifdef CONFIG_VMAP_STACK

	li	r11, RPN_PATTERN

	mtspr	SPRN_DAR, r11	/* Tag DAR, to be used in DTLB Error */

#endif

	EXCEPTION_PROLOG_1

	EXCEPTION_PROLOG_2

	EXCEPTION_PROLOG_2 handle_dar_dsisr=1

	get_and_save_dar_dsisr_on_stack r4, r5, r11

	andis.	r10,r5,DSISR_NOHPTE@h

	beq+	.Ldtlbie

	tlbie	r4

.Ldtlbie:

#ifndef CONFIG_VMAP_STACK

	li	r10,RPN_PATTERN

	mtspr	SPRN_DAR,r10	/* Tag DAR, to be used in DTLB Error */

#endif

	/* 0x300 is DataAccess exception, needed by bad_page_fault() */

	EXC_XFER_LITE(0x300, handle_page_fault)
@@ -491,22 +497,29 @@ DARFixed:/* Return from dcbx instruction bug workaround */ 
	rfi

#endif



stack_overflow:

	vmap_stack_overflow_exception



/* On the MPC8xx, these next four traps are used for development

 * support of breakpoints and such.  Someday I will get around to

 * using them.

 */

do_databreakpoint:

	EXCEPTION_PROLOG_1

	EXCEPTION_PROLOG_2

	EXCEPTION_PROLOG_2 handle_dar_dsisr=1

	addi	r3,r1,STACK_FRAME_OVERHEAD

	mfspr	r4,SPRN_BAR

	stw	r4,_DAR(r11)

#ifdef CONFIG_VMAP_STACK

	lwz	r5,_DSISR(r11)

#else

	mfspr	r5,SPRN_DSISR

#endif

	EXC_XFER_STD(0x1c00, do_break)



	. = 0x1c00

DataBreakpoint:

	EXCEPTION_PROLOG_0

	EXCEPTION_PROLOG_0 handle_dar_dsisr=1

	mfspr	r11, SPRN_SRR0

	cmplwi	cr1, r11, (.Ldtlbie - PAGE_OFFSET)@l

	cmplwi	cr7, r11, (.Litlbie - PAGE_OFFSET)@l
@@ -655,7 +668,14 @@ FixupDAR:/* Entry point for dcbx workaround. */ 
152:

	mfdar	r11

	mtctr	r11			/* restore ctr reg from DAR */

#ifdef CONFIG_VMAP_STACK

	mfspr	r11, SPRN_SPRG_THREAD

	stw	r10, DAR(r11)

	mfspr	r10, SPRN_DSISR

	stw	r10, DSISR(r11)

#else

	mtdar	r10			/* save fault EA to DAR */

#endif

	mfspr	r10,SPRN_M_TW

	b	DARFixed		/* Go back to normal TLB handling */

arch/powerpc/platforms/Kconfig.cputype

+1 −0
Original line number Diff line number Diff line
@@ -49,6 +49,7 @@ config PPC_8xx 
	select PPC_HAVE_KUEP

	select PPC_HAVE_KUAP

	select PPC_MM_SLICES if HUGETLB_PAGE

	select HAVE_ARCH_VMAP_STACK



config 40x

	bool "AMCC 40x"

CRA Git | Maintained and supported by SUSTech CRA and CCSE