powerpc: flexible GPR range save/restore macros

Introduce macros that operate on a (start, end) range of GPRs, which
reduces lines of code and need to do mental arithmetic while reading the
code.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211022061322.2671178-1-npiggin@gmail.com

9 files changed, 42 insertions, 75 deletions

diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 61fdd53cdd9a..c62dd9815965 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -90,8 +90,7 @@ transfer_to_syscall:
 	stw	r12,8(r1)
 	stw	r2,_TRAP(r1)
 	SAVE_GPR(0, r1)
-	SAVE_4GPRS(3, r1)
-	SAVE_2GPRS(7, r1)
+	SAVE_GPRS(3, 8, r1)
 	addi	r2,r10,-THREAD
 	SAVE_NVGPRS(r1)
 
@@ -139,7 +138,7 @@ syscall_exit_finish:
 	mtxer	r5
 	lwz	r0,GPR0(r1)
 	lwz	r3,GPR3(r1)
-	REST_8GPRS(4,r1)
+	REST_GPRS(4, 11, r1)
 	lwz	r12,GPR12(r1)
 	b	1b
 
@@ -232,9 +231,9 @@ fast_exception_return:
 	beq	3f			/* if not, we've got problems */
 #endif
 
-2:	REST_4GPRS(3, r11)
+2:	REST_GPRS(3, 6, r11)
 	lwz	r10,_CCR(r11)
-	REST_2GPRS(1, r11)
+	REST_GPRS(1, 2, r11)
 	mtcr	r10
 	lwz	r10,_LINK(r11)
 	mtlr	r10
@@ -298,16 +297,14 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
 	 * the reliable stack unwinder later on. Clear it.
 	 */
 	stw	r0,8(r1)
-	REST_4GPRS(7, r1)
-	REST_2GPRS(11, r1)
+	REST_GPRS(7, 12, r1)
 
 	mtcr	r3
 	mtlr	r4
 	mtctr	r5
 	mtspr	SPRN_XER,r6
 
-	REST_4GPRS(2, r1)
-	REST_GPR(6, r1)
+	REST_GPRS(2, 6, r1)
 	REST_GPR(0, r1)
 	REST_GPR(1, r1)
 	rfi
@@ -341,8 +338,7 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
 	lwz	r6,_CCR(r1)
 	li	r0,0
 
-	REST_4GPRS(7, r1)
-	REST_2GPRS(11, r1)
+	REST_GPRS(7, 12, r1)
 
 	mtlr	r3
 	mtctr	r4
@@ -354,7 +350,7 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
 	 */
 	stw	r0,8(r1)
 
-	REST_4GPRS(2, r1)
+	REST_GPRS(2, 5, r1)
 
 	bne-	cr1,1f /* emulate stack store */
 	mtcr	r6
@@ -430,8 +426,7 @@ _ASM_NOKPROBE_SYMBOL(interrupt_return)
 	bne	interrupt_return;					\
 	lwz	r0,GPR0(r1);						\
 	lwz	r2,GPR2(r1);						\
-	REST_4GPRS(3, r1);						\
-	REST_2GPRS(7, r1);						\
+	REST_GPRS(3, 8, r1);						\
 	lwz	r10,_XER(r1);						\
 	lwz	r11,_CTR(r1);						\
 	mtspr	SPRN_XER,r10;						\
diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S
index 711c66b76df1..67dc4e3179a0 100644
--- a/arch/powerpc/kernel/exceptions-64e.S
+++ b/arch/powerpc/kernel/exceptions-64e.S
@@ -198,8 +198,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV)
 
 	stdcx.	r0,0,r1		/* to clear the reservation */
 
-	REST_4GPRS(2, r1)
-	REST_4GPRS(6, r1)
+	REST_GPRS(2, 9, r1)
 
 	ld	r10,_CTR(r1)
 	ld	r11,_XER(r1)
@@ -375,9 +374,7 @@ ret_from_mc_except:
 exc_##n##_common:							    \
 	std	r0,GPR0(r1);		/* save r0 in stackframe */	    \
 	std	r2,GPR2(r1);		/* save r2 in stackframe */	    \
-	SAVE_4GPRS(3, r1);		/* save r3 - r6 in stackframe */    \
-	SAVE_2GPRS(7, r1);		/* save r7, r8 in stackframe */	    \
-	std	r9,GPR9(r1);		/* save r9 in stackframe */	    \
+	SAVE_GPRS(3, 9, r1);		/* save r3 - r9 in stackframe */    \
 	std	r10,_NIP(r1);		/* save SRR0 to stackframe */	    \
 	std	r11,_MSR(r1);		/* save SRR1 to stackframe */	    \
 	beq	2f;			/* if from kernel mode */	    \
@@ -1061,9 +1058,7 @@ bad_stack_book3e:
 	std	r11,_ESR(r1)
 	std	r0,GPR0(r1);		/* save r0 in stackframe */	    \
 	std	r2,GPR2(r1);		/* save r2 in stackframe */	    \
-	SAVE_4GPRS(3, r1);		/* save r3 - r6 in stackframe */    \
-	SAVE_2GPRS(7, r1);		/* save r7, r8 in stackframe */	    \
-	std	r9,GPR9(r1);		/* save r9 in stackframe */	    \
+	SAVE_GPRS(3, 9, r1);		/* save r3 - r9 in stackframe */    \
 	ld	r3,PACA_EXGEN+EX_R10(r13);/* get back r10 */		    \
 	ld	r4,PACA_EXGEN+EX_R11(r13);/* get back r11 */		    \
 	mfspr	r5,SPRN_SPRG_GEN_SCRATCH;/* get back r13 XXX can be wrong */ \
@@ -1077,8 +1072,7 @@ bad_stack_book3e:
 	std	r10,_LINK(r1)
 	std	r11,_CTR(r1)
 	std	r12,_XER(r1)
-	SAVE_10GPRS(14,r1)
-	SAVE_8GPRS(24,r1)
+	SAVE_GPRS(14, 31, r1)
 	lhz	r12,PACA_TRAP_SAVE(r13)
 	std	r12,_TRAP(r1)
 	addi	r11,r1,INT_FRAME_SIZE
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index eaf1f72131a1..277eccf0f086 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -574,8 +574,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
 	ld	r10,IAREA+EX_CTR(r13)
 	std	r10,_CTR(r1)
 	std	r2,GPR2(r1)		/* save r2 in stackframe	*/
-	SAVE_4GPRS(3, r1)		/* save r3 - r6 in stackframe   */
-	SAVE_2GPRS(7, r1)		/* save r7, r8 in stackframe	*/
+	SAVE_GPRS(3, 8, r1)		/* save r3 - r8 in stackframe   */
 	mflr	r9			/* Get LR, later save to stack	*/
 	ld	r2,PACATOC(r13)		/* get kernel TOC into r2	*/
 	std	r9,_LINK(r1)
@@ -693,8 +692,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
 	mtlr	r9
 	ld	r9,_CCR(r1)
 	mtcr	r9
-	REST_8GPRS(2, r1)
-	REST_4GPRS(10, r1)
+	REST_GPRS(2, 13, r1)
 	REST_GPR(0, r1)
 	/* restore original r1. */
 	ld	r1,GPR1(r1)
diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
index 6b1ec9e3541b..25887303651a 100644
--- a/arch/powerpc/kernel/head_32.h
+++ b/arch/powerpc/kernel/head_32.h
@@ -115,8 +115,7 @@ _ASM_NOKPROBE_SYMBOL(\name\()_virt)
 	stw	r10,8(r1)
 	li	r10, \trapno
 	stw	r10,_TRAP(r1)
-	SAVE_4GPRS(3, r1)
-	SAVE_2GPRS(7, r1)
+	SAVE_GPRS(3, 8, r1)
 	SAVE_NVGPRS(r1)
 	stw	r2,GPR2(r1)
 	stw	r12,_NIP(r1)
diff --git a/arch/powerpc/kernel/head_booke.h b/arch/powerpc/kernel/head_booke.h
index ef8d1b1c234e..bb6d5d0fc4ac 100644
--- a/arch/powerpc/kernel/head_booke.h
+++ b/arch/powerpc/kernel/head_booke.h
@@ -87,8 +87,7 @@ END_BTB_FLUSH_SECTION
 	stw	r10, 8(r1)
 	li	r10, \trapno
 	stw	r10,_TRAP(r1)
-	SAVE_4GPRS(3, r1)
-	SAVE_2GPRS(7, r1)
+	SAVE_GPRS(3, 8, r1)
 	SAVE_NVGPRS(r1)
 	stw	r2,GPR2(r1)
 	stw	r12,_NIP(r1)
diff --git a/arch/powerpc/kernel/interrupt_64.S b/arch/powerpc/kernel/interrupt_64.S
index ec950b08a8dc..2ad223597ca2 100644
--- a/arch/powerpc/kernel/interrupt_64.S
+++ b/arch/powerpc/kernel/interrupt_64.S
@@ -162,10 +162,9 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
 	 * The value of AMR only matters while we're in the kernel.
 	 */
 	mtcr	r2
-	ld	r2,GPR2(r1)
-	ld	r3,GPR3(r1)
-	ld	r13,GPR13(r1)
-	ld	r1,GPR1(r1)
+	REST_GPRS(2, 3, r1)
+	REST_GPR(13, r1)
+	REST_GPR(1, r1)
 	RFSCV_TO_USER
 	b	.	/* prevent speculative execution */
 
@@ -183,9 +182,8 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
 	mtctr	r3
 	mtlr	r4
 	mtspr	SPRN_XER,r5
-	REST_10GPRS(2, r1)
-	REST_2GPRS(12, r1)
-	ld	r1,GPR1(r1)
+	REST_GPRS(2, 13, r1)
+	REST_GPR(1, r1)
 	RFI_TO_USER
 .Lsyscall_vectored_\name\()_rst_end:
 
@@ -374,10 +372,9 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
 	 * The value of AMR only matters while we're in the kernel.
 	 */
 	mtcr	r2
-	ld	r2,GPR2(r1)
-	ld	r3,GPR3(r1)
-	ld	r13,GPR13(r1)
-	ld	r1,GPR1(r1)
+	REST_GPRS(2, 3, r1)
+	REST_GPR(13, r1)
+	REST_GPR(1, r1)
 	RFI_TO_USER
 	b	.	/* prevent speculative execution */
 
@@ -388,8 +385,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
 	mtctr	r3
 	mtspr	SPRN_XER,r4
 	ld	r0,GPR0(r1)
-	REST_8GPRS(4, r1)
-	ld	r12,GPR12(r1)
+	REST_GPRS(4, 12, r1)
 	b	.Lsyscall_restore_regs_cont
 .Lsyscall_rst_end:
 
@@ -518,17 +514,14 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
 	ld	r6,_XER(r1)
 	li	r0,0
 
-	REST_4GPRS(7, r1)
-	REST_2GPRS(11, r1)
-	REST_GPR(13, r1)
+	REST_GPRS(7, 13, r1)
 
 	mtcr	r3
 	mtlr	r4
 	mtctr	r5
 	mtspr	SPRN_XER,r6
 
-	REST_4GPRS(2, r1)
-	REST_GPR(6, r1)
+	REST_GPRS(2, 6, r1)
 	REST_GPR(0, r1)
 	REST_GPR(1, r1)
 	.ifc \srr,srr
@@ -625,8 +618,7 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
 	ld	r6,_CCR(r1)
 	li	r0,0
 
-	REST_4GPRS(7, r1)
-	REST_2GPRS(11, r1)
+	REST_GPRS(7, 12, r1)
 
 	mtlr	r3
 	mtctr	r4
@@ -638,7 +630,7 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
 	 */
 	std	r0,STACK_FRAME_OVERHEAD-16(r1)
 
-	REST_4GPRS(2, r1)
+	REST_GPRS(2, 5, r1)
 
 	bne-	cr1,1f /* emulate stack store */
 	mtcr	r6
diff --git a/arch/powerpc/kernel/optprobes_head.S b/arch/powerpc/kernel/optprobes_head.S
index 19ea3312403c..5c7f0b4b784b 100644
--- a/arch/powerpc/kernel/optprobes_head.S
+++ b/arch/powerpc/kernel/optprobes_head.S
@@ -10,8 +10,8 @@
 #include <asm/asm-offsets.h>
 
 #ifdef CONFIG_PPC64
-#define SAVE_30GPRS(base) SAVE_10GPRS(2,base); SAVE_10GPRS(12,base); SAVE_10GPRS(22,base)
-#define REST_30GPRS(base) REST_10GPRS(2,base); REST_10GPRS(12,base); REST_10GPRS(22,base)
+#define SAVE_30GPRS(base) SAVE_GPRS(2, 31, base)
+#define REST_30GPRS(base) REST_GPRS(2, 31, base)
 #define TEMPLATE_FOR_IMM_LOAD_INSNS	nop; nop; nop; nop; nop
 #else
 #define SAVE_30GPRS(base) stmw	r2, GPR2(base)
diff --git a/arch/powerpc/kernel/tm.S b/arch/powerpc/kernel/tm.S
index 2b91f233b05d..3beecc32940b 100644
--- a/arch/powerpc/kernel/tm.S
+++ b/arch/powerpc/kernel/tm.S
@@ -226,11 +226,8 @@ _GLOBAL(tm_reclaim)
 
 	/* Sync the userland GPRs 2-12, 14-31 to thread->regs: */
 	SAVE_GPR(0, r7)				/* user r0 */
-	SAVE_GPR(2, r7)				/* user r2 */
-	SAVE_4GPRS(3, r7)			/* user r3-r6 */
-	SAVE_GPR(8, r7)				/* user r8 */
-	SAVE_GPR(9, r7)				/* user r9 */
-	SAVE_GPR(10, r7)			/* user r10 */
+	SAVE_GPRS(2, 6, r7)			/* user r2-r6 */
+	SAVE_GPRS(8, 10, r7)			/* user r8-r10 */
 	ld	r3, GPR1(r1)			/* user r1 */
 	ld	r4, GPR7(r1)			/* user r7 */
 	ld	r5, GPR11(r1)			/* user r11 */
@@ -445,12 +442,8 @@ restore_gprs:
 	ld	r6, THREAD_TM_PPR(r3)
 
 	REST_GPR(0, r7)				/* GPR0 */
-	REST_2GPRS(2, r7)			/* GPR2-3 */
-	REST_GPR(4, r7)				/* GPR4 */
-	REST_4GPRS(8, r7)			/* GPR8-11 */
-	REST_2GPRS(12, r7)			/* GPR12-13 */
-
-	REST_NVGPRS(r7)				/* GPR14-31 */
+	REST_GPRS(2, 4, r7)			/* GPR2-4 */
+	REST_GPRS(8, 31, r7)			/* GPR8-31 */
 
 	/* Load up PPR and DSCR here so we don't run with user values for long */
 	mtspr	SPRN_DSCR, r5
diff --git a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
index f9fd5f743eba..d636fc755f60 100644
--- a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
+++ b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
@@ -41,15 +41,14 @@ _GLOBAL(ftrace_regs_caller)
 
 	/* Save all gprs to pt_regs */
 	SAVE_GPR(0, r1)
-	SAVE_10GPRS(2, r1)
+	SAVE_GPRS(2, 11, r1)
 
 	/* Ok to continue? */
 	lbz	r3, PACA_FTRACE_ENABLED(r13)
 	cmpdi	r3, 0
 	beq	ftrace_no_trace
 
-	SAVE_10GPRS(12, r1)
-	SAVE_10GPRS(22, r1)
+	SAVE_GPRS(12, 31, r1)
 
 	/* Save previous stack pointer (r1) */
 	addi	r8, r1, SWITCH_FRAME_SIZE
@@ -108,10 +107,8 @@ ftrace_regs_call:
 #endif
 
 	/* Restore gprs */
-	REST_GPR(0,r1)
-	REST_10GPRS(2,r1)
-	REST_10GPRS(12,r1)
-	REST_10GPRS(22,r1)
+	REST_GPR(0, r1)
+	REST_GPRS(2, 31, r1)
 
 	/* Restore possibly modified LR */
 	ld	r0, _LINK(r1)
@@ -157,7 +154,7 @@ _GLOBAL(ftrace_caller)
 	stdu	r1, -SWITCH_FRAME_SIZE(r1)
 
 	/* Save all gprs to pt_regs */
-	SAVE_8GPRS(3, r1)
+	SAVE_GPRS(3, 10, r1)
 
 	lbz	r3, PACA_FTRACE_ENABLED(r13)
 	cmpdi	r3, 0
@@ -194,7 +191,7 @@ ftrace_call:
 	mtctr	r3
 
 	/* Restore gprs */
-	REST_8GPRS(3,r1)
+	REST_GPRS(3, 10, r1)
 
 	/* Restore callee's TOC */
 	ld	r2, 24(r1)