powerpc/64s/exception: Introduce INT_DEFINE parameter block for code generation

The code generation macro arguments are difficult to read, and
defaults can't easily be used.

This introduces a block where parameters can be set for interrupt
handler code generation by the subsequent macros, and adds the first
generation macro for interrupt entry.

One interrupt handler is converted to the new macros to demonstrate
the change, the rest will be coverted all at once.

No generated code change.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200225173541.1549955-2-npiggin@gmail.com

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

@@ -193,6 +193,61 @@ END_FTR_SECTION_NESTED(ftr,ftr,943)
 	mtctr	reg;							\
 	bctr
 
+/*
+ * Interrupt code generation macros
+ */
+#define IVEC		.L_IVEC_\name\()
+#define IHSRR		.L_IHSRR_\name\()
+#define IAREA		.L_IAREA_\name\()
+#define IDAR		.L_IDAR_\name\()
+#define IDSISR		.L_IDSISR_\name\()
+#define ISET_RI		.L_ISET_RI_\name\()
+#define IEARLY		.L_IEARLY_\name\()
+#define IMASK		.L_IMASK_\name\()
+#define IKVM_REAL	.L_IKVM_REAL_\name\()
+#define IKVM_VIRT	.L_IKVM_VIRT_\name\()
+
+#define INT_DEFINE_BEGIN(n)						\
+.macro int_define_ ## n name
+
+#define INT_DEFINE_END(n)						\
+.endm ;									\
+int_define_ ## n n ;							\
+do_define_int n
+
+.macro do_define_int name
+	.ifndef IVEC
+		.error "IVEC not defined"
+	.endif
+	.ifndef IHSRR
+		IHSRR=EXC_STD
+	.endif
+	.ifndef IAREA
+		IAREA=PACA_EXGEN
+	.endif
+	.ifndef IDAR
+		IDAR=0
+	.endif
+	.ifndef IDSISR
+		IDSISR=0
+	.endif
+	.ifndef ISET_RI
+		ISET_RI=1
+	.endif
+	.ifndef IEARLY
+		IEARLY=0
+	.endif
+	.ifndef IMASK
+		IMASK=0
+	.endif
+	.ifndef IKVM_REAL
+		IKVM_REAL=0
+	.endif
+	.ifndef IKVM_VIRT
+		IKVM_VIRT=0
+	.endif
+.endm
+
 .macro INT_KVM_HANDLER name, vec, hsrr, area, skip
 	TRAMP_KVM_BEGIN(\name\()_kvm)
 	KVM_HANDLER \vec, \hsrr, \area, \skip
@@ -474,7 +529,7 @@ END_FTR_SECTION_NESTED(CPU_FTR_HAS_PPR,CPU_FTR_HAS_PPR,948)
 	 */
 	GET_SCRATCH0(r10)
 	std	r10,\area\()+EX_R13(r13)
-	.if \dar
+	.if \dar == 1
 	.if \hsrr
 	mfspr	r10,SPRN_HDAR
 	.else
@@ -482,7 +537,7 @@ END_FTR_SECTION_NESTED(CPU_FTR_HAS_PPR,CPU_FTR_HAS_PPR,948)
 	.endif
 	std	r10,\area\()+EX_DAR(r13)
 	.endif
-	.if \dsisr
+	.if \dsisr == 1
 	.if \hsrr
 	mfspr	r10,SPRN_HDSISR
 	.else
@@ -506,6 +561,14 @@ END_FTR_SECTION_NESTED(CPU_FTR_HAS_PPR,CPU_FTR_HAS_PPR,948)
 	.endif
 .endm
 
+.macro GEN_INT_ENTRY name, virt, ool=0
+	.if ! \virt
+		INT_HANDLER \name, IVEC, \ool, IEARLY, \virt, IHSRR, IAREA, ISET_RI, IDAR, IDSISR, IMASK, IKVM_REAL
+	.else
+		INT_HANDLER \name, IVEC, \ool, IEARLY, \virt, IHSRR, IAREA, ISET_RI, IDAR, IDSISR, IMASK, IKVM_VIRT
+	.endif
+.endm
+
 /*
  * On entry r13 points to the paca, r9-r13 are saved in the paca,
  * r9 contains the saved CR, r11 and r12 contain the saved SRR0 and
@@ -1143,12 +1206,18 @@ END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
 	bl	unrecoverable_exception
 	b	.
 
+INT_DEFINE_BEGIN(data_access)
+	IVEC=0x300
+	IDAR=1
+	IDSISR=1
+	IKVM_REAL=1
+INT_DEFINE_END(data_access)
 
 EXC_REAL_BEGIN(data_access, 0x300, 0x80)
-	INT_HANDLER data_access, 0x300, ool=1, dar=1, dsisr=1, kvm=1
+	GEN_INT_ENTRY data_access, virt=0, ool=1
 EXC_REAL_END(data_access, 0x300, 0x80)
 EXC_VIRT_BEGIN(data_access, 0x4300, 0x80)
-	INT_HANDLER data_access, 0x300, virt=1, dar=1, dsisr=1
+	GEN_INT_ENTRY data_access, virt=1
 EXC_VIRT_END(data_access, 0x4300, 0x80)
 INT_KVM_HANDLER data_access, 0x300, EXC_STD, PACA_EXGEN, 1
 EXC_COMMON_BEGIN(data_access_common)