powerpc/book3s: Add flush_tlb operation in cpu_spec.

This patch introduces flush_tlb operation in cpu_spec structure. This will
help us to invoke appropriate CPU-side flush tlb routine. This patch
adds the foundation to invoke CPU specific flush routine for respective
architectures. Currently this patch introduce flush_tlb for p7 and p8.

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/include/asm/cputable.h

@@ -97,6 +97,11 @@ struct cpu_spec {
 	 */
 	long		(*machine_check_early)(struct pt_regs *regs);
 
+	/*
+	 * Processor specific routine to flush tlbs.
+	 */
+	void		(*flush_tlb)(unsigned long inval_selector);
+
 };
 
 extern struct cpu_spec		*cur_cpu_spec;

arch/powerpc/kernel/cpu_setup_power.S

@@ -29,7 +29,7 @@ _GLOBAL(__setup_cpu_power7)
 	mtspr	SPRN_LPID,r0
 	mfspr	r3,SPRN_LPCR
 	bl	__init_LPCR
-	bl	__init_TLB
+	bl	__init_tlb_power7
 	mtlr	r11
 	blr
 
@@ -42,7 +42,7 @@ _GLOBAL(__restore_cpu_power7)
 	mtspr	SPRN_LPID,r0
 	mfspr	r3,SPRN_LPCR
 	bl	__init_LPCR
-	bl	__init_TLB
+	bl	__init_tlb_power7
 	mtlr	r11
 	blr
 
@@ -59,7 +59,7 @@ _GLOBAL(__setup_cpu_power8)
 	oris	r3, r3, LPCR_AIL_3@h
 	bl	__init_LPCR
 	bl	__init_HFSCR
-	bl	__init_TLB
+	bl	__init_tlb_power8
 	bl	__init_PMU_HV
 	mtlr	r11
 	blr
@@ -78,7 +78,7 @@ _GLOBAL(__restore_cpu_power8)
 	oris	r3, r3, LPCR_AIL_3@h
 	bl	__init_LPCR
 	bl	__init_HFSCR
-	bl	__init_TLB
+	bl	__init_tlb_power8
 	bl	__init_PMU_HV
 	mtlr	r11
 	blr
@@ -134,15 +134,31 @@ __init_HFSCR:
 	mtspr	SPRN_HFSCR,r3
 	blr
 
-__init_TLB:
-	/*
-	 * Clear the TLB using the "IS 3" form of tlbiel instruction
-	 * (invalidate by congruence class). P7 has 128 CCs, P8 has 512
-	 * so we just always do 512
-	 */
+/*
+ * Clear the TLB using the specified IS form of tlbiel instruction
+ * (invalidate by congruence class). P7 has 128 CCs., P8 has 512.
+ *
+ * r3 = IS field
+ */
+__init_tlb_power7:
+	li	r3,0xc00	/* IS field = 0b11 */
+_GLOBAL(__flush_tlb_power7)
+	li	r6,128
+	mtctr	r6
+	mr	r7,r3		/* IS field */
+	ptesync
+2:	tlbiel	r7
+	addi	r7,r7,0x1000
+	bdnz	2b
+	ptesync
+1:	blr
+
+__init_tlb_power8:
+	li	r3,0xc00	/* IS field = 0b11 */
+_GLOBAL(__flush_tlb_power8)
 	li	r6,512
 	mtctr	r6
-	li	r7,0xc00	/* IS field = 0b11 */
+	mr	r7,r3		/* IS field */
 	ptesync
 2:	tlbiel	r7
 	addi	r7,r7,0x1000

arch/powerpc/kernel/cputable.c

@@ -71,6 +71,8 @@ extern void __restore_cpu_power7(void);
 extern void __setup_cpu_power8(unsigned long offset, struct cpu_spec* spec);
 extern void __restore_cpu_power8(void);
 extern void __restore_cpu_a2(void);
+extern void __flush_tlb_power7(unsigned long inval_selector);
+extern void __flush_tlb_power8(unsigned long inval_selector);
 #endif /* CONFIG_PPC64 */
 #if defined(CONFIG_E500)
 extern void __setup_cpu_e5500(unsigned long offset, struct cpu_spec* spec);
@@ -440,6 +442,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
 		.oprofile_cpu_type	= "ppc64/ibm-compat-v1",
 		.cpu_setup		= __setup_cpu_power7,
 		.cpu_restore		= __restore_cpu_power7,
+		.flush_tlb		= __flush_tlb_power7,
 		.platform		= "power7",
 	},
 	{	/* 2.07-compliant processor, i.e. Power8 "architected" mode */
@@ -456,6 +459,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
 		.oprofile_cpu_type	= "ppc64/ibm-compat-v1",
 		.cpu_setup		= __setup_cpu_power8,
 		.cpu_restore		= __restore_cpu_power8,
+		.flush_tlb		= __flush_tlb_power8,
 		.platform		= "power8",
 	},
 	{	/* Power7 */
@@ -474,6 +478,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
 		.oprofile_type		= PPC_OPROFILE_POWER4,
 		.cpu_setup		= __setup_cpu_power7,
 		.cpu_restore		= __restore_cpu_power7,
+		.flush_tlb		= __flush_tlb_power7,
 		.platform		= "power7",
 	},
 	{	/* Power7+ */
@@ -492,6 +497,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
 		.oprofile_type		= PPC_OPROFILE_POWER4,
 		.cpu_setup		= __setup_cpu_power7,
 		.cpu_restore		= __restore_cpu_power7,
+		.flush_tlb		= __flush_tlb_power7,
 		.platform		= "power7+",
 	},
 	{	/* Power8E */
@@ -510,6 +516,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
 		.oprofile_type		= PPC_OPROFILE_INVALID,
 		.cpu_setup		= __setup_cpu_power8,
 		.cpu_restore		= __restore_cpu_power8,
+		.flush_tlb		= __flush_tlb_power8,
 		.platform		= "power8",
 	},
 	{	/* Power8 */
@@ -528,6 +535,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
 		.oprofile_type		= PPC_OPROFILE_INVALID,
 		.cpu_setup		= __setup_cpu_power8,
 		.cpu_restore		= __restore_cpu_power8,
+		.flush_tlb		= __flush_tlb_power8,
 		.platform		= "power8",
 	},
 	{	/* Cell Broadband Engine */

arch/powerpc/kvm/book3s_hv_ras.c

@@ -58,18 +58,6 @@ static void reload_slb(struct kvm_vcpu *vcpu)
 	}
 }
 
-/* POWER7 TLB flush */
-static void flush_tlb_power7(struct kvm_vcpu *vcpu)
-{
-	unsigned long i, rb;
-
-	rb = TLBIEL_INVAL_SET_LPID;
-	for (i = 0; i < POWER7_TLB_SETS; ++i) {
-		asm volatile("tlbiel %0" : : "r" (rb));
-		rb += 1 << TLBIEL_INVAL_SET_SHIFT;
-	}
-}
-
 /*
  * On POWER7, see if we can handle a machine check that occurred inside
  * the guest in real mode, without switching to the host partition.
@@ -96,7 +84,8 @@ static long kvmppc_realmode_mc_power7(struct kvm_vcpu *vcpu)
 				   DSISR_MC_SLB_PARITY | DSISR_MC_DERAT_MULTI);
 		}
 		if (dsisr & DSISR_MC_TLB_MULTI) {
-			flush_tlb_power7(vcpu);
+			if (cur_cpu_spec && cur_cpu_spec->flush_tlb)
+				cur_cpu_spec->flush_tlb(TLBIEL_INVAL_SET_LPID);
 			dsisr &= ~DSISR_MC_TLB_MULTI;
 		}
 		/* Any other errors we don't understand? */
@@ -113,7 +102,8 @@ static long kvmppc_realmode_mc_power7(struct kvm_vcpu *vcpu)
 		reload_slb(vcpu);
 		break;
 	case SRR1_MC_IFETCH_TLBMULTI:
-		flush_tlb_power7(vcpu);
+		if (cur_cpu_spec && cur_cpu_spec->flush_tlb)
+			cur_cpu_spec->flush_tlb(TLBIEL_INVAL_SET_LPID);
 		break;
 	default:
 		handled = 0;