From: Christophe Leroy <christophe.leroy@c-s.fr>
Date: Fri, 9 Nov 2018 17:33:30 +0000 (+0000)
Subject: powerpc/44x: use patch_sites for TLB handlers patching
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=6c16816b91a64a33033930fbe2ae3f02e012d8bd;p=openwrt%2Fstaging%2Fblogic.git

powerpc/44x: use patch_sites for TLB handlers patching

Use patch sites and associated helpers to manage TLB handlers
patching instead of hardcoding.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---

diff --git a/arch/powerpc/include/asm/nohash/32/mmu-44x.h b/arch/powerpc/include/asm/nohash/32/mmu-44x.h
index 295b3dbb2698..28aa3b339c5e 100644
--- a/arch/powerpc/include/asm/nohash/32/mmu-44x.h
+++ b/arch/powerpc/include/asm/nohash/32/mmu-44x.h
@@ -111,6 +111,9 @@ typedef struct {
 	unsigned long	vdso_base;
 } mm_context_t;
 
+/* patch sites */
+extern s32 patch__tlb_44x_hwater_D, patch__tlb_44x_hwater_I;
+
 #endif /* !__ASSEMBLY__ */
 
 #ifndef CONFIG_PPC_EARLY_DEBUG_44x
diff --git a/arch/powerpc/kernel/head_44x.S b/arch/powerpc/kernel/head_44x.S
index 37e4a7cf0065..bf23c19c92d6 100644
--- a/arch/powerpc/kernel/head_44x.S
+++ b/arch/powerpc/kernel/head_44x.S
@@ -40,6 +40,7 @@
 #include <asm/ptrace.h>
 #include <asm/synch.h>
 #include <asm/export.h>
+#include <asm/code-patching-asm.h>
 #include "head_booke.h"
 
 
@@ -382,10 +383,9 @@ interrupt_base:
 	/* Increment, rollover, and store TLB index */
 	addi	r13,r13,1
 
+	patch_site 0f, patch__tlb_44x_hwater_D
 	/* Compare with watermark (instruction gets patched) */
-	.globl tlb_44x_patch_hwater_D
-tlb_44x_patch_hwater_D:
-	cmpwi	0,r13,1			/* reserve entries */
+0:	cmpwi	0,r13,1			/* reserve entries */
 	ble	5f
 	li	r13,0
 5:
@@ -478,10 +478,9 @@ tlb_44x_patch_hwater_D:
 	/* Increment, rollover, and store TLB index */
 	addi	r13,r13,1
 
+	patch_site 0f, patch__tlb_44x_hwater_I
 	/* Compare with watermark (instruction gets patched) */
-	.globl tlb_44x_patch_hwater_I
-tlb_44x_patch_hwater_I:
-	cmpwi	0,r13,1			/* reserve entries */
+0:	cmpwi	0,r13,1			/* reserve entries */
 	ble	5f
 	li	r13,0
 5:
diff --git a/arch/powerpc/mm/44x_mmu.c b/arch/powerpc/mm/44x_mmu.c
index 12d92518e898..ea2b9af08a48 100644
--- a/arch/powerpc/mm/44x_mmu.c
+++ b/arch/powerpc/mm/44x_mmu.c
@@ -29,6 +29,7 @@
 #include <asm/mmu.h>
 #include <asm/page.h>
 #include <asm/cacheflush.h>
+#include <asm/code-patching.h>
 
 #include "mmu_decl.h"
 
@@ -43,22 +44,13 @@ unsigned long tlb_47x_boltmap[1024/8];
 
 static void ppc44x_update_tlb_hwater(void)
 {
-	extern unsigned int tlb_44x_patch_hwater_D[];
-	extern unsigned int tlb_44x_patch_hwater_I[];
-
 	/* The TLB miss handlers hard codes the watermark in a cmpli
 	 * instruction to improve performances rather than loading it
 	 * from the global variable. Thus, we patch the instructions
 	 * in the 2 TLB miss handlers when updating the value
 	 */
-	tlb_44x_patch_hwater_D[0] = (tlb_44x_patch_hwater_D[0] & 0xffff0000) |
-		tlb_44x_hwater;
-	flush_icache_range((unsigned long)&tlb_44x_patch_hwater_D[0],
-			   (unsigned long)&tlb_44x_patch_hwater_D[1]);
-	tlb_44x_patch_hwater_I[0] = (tlb_44x_patch_hwater_I[0] & 0xffff0000) |
-		tlb_44x_hwater;
-	flush_icache_range((unsigned long)&tlb_44x_patch_hwater_I[0],
-			   (unsigned long)&tlb_44x_patch_hwater_I[1]);
+	modify_instruction_site(&patch__tlb_44x_hwater_D, 0xffff, tlb_44x_hwater);
+	modify_instruction_site(&patch__tlb_44x_hwater_I, 0xffff, tlb_44x_hwater);
 }
 
 /*