X-Git-Url: https://git.proxmox.com/?a=blobdiff_plain;f=arch%2Fpowerpc%2Fkernel%2Fentry_64.S;h=7188fc900db6bd52b4aadfdbe72e4d493a6a4776;hb=4dcfe4ccc3449aa363215a32747c1a7e87af8114;hp=250bc8e822058f9ee4a0cf320150d355ed9516a2;hpb=85e6bb465c55985059dbad19aa9e12f0a7bb94d5;p=mirror_ubuntu-bionic-kernel.git

diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 250bc8e82205..7188fc900db6 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -25,6 +25,7 @@
 #include <asm/page.h>
 #include <asm/mmu.h>
 #include <asm/thread_info.h>
+#include <asm/code-patching-asm.h>
 #include <asm/ppc_asm.h>
 #include <asm/asm-offsets.h>
 #include <asm/cputable.h>
@@ -497,6 +498,57 @@ _GLOBAL(ret_from_kernel_thread)
 	li	r3,0
 	b	.Lsyscall_exit
 
+#ifdef CONFIG_PPC_BOOK3S_64
+
+#define FLUSH_COUNT_CACHE	\
+1:	nop;			\
+	patch_site 1b, patch__call_flush_count_cache
+
+
+#define BCCTR_FLUSH	.long 0x4c400420
+
+.macro nops number
+	.rept \number
+	nop
+	.endr
+.endm
+
+.balign 32
+.global flush_count_cache
+flush_count_cache:
+	/* Save LR into r9 */
+	mflr	r9
+
+	.rept 64
+	bl	.+4
+	.endr
+	b	1f
+	nops	6
+
+	.balign 32
+	/* Restore LR */
+1:	mtlr	r9
+	li	r9,0x7fff
+	mtctr	r9
+
+	BCCTR_FLUSH
+
+2:	nop
+	patch_site 2b patch__flush_count_cache_return
+
+	nops	3
+
+	.rept 278
+	.balign 32
+	BCCTR_FLUSH
+	nops	7
+	.endr
+
+	blr
+#else
+#define FLUSH_COUNT_CACHE
+#endif /* CONFIG_PPC_BOOK3S_64 */
+
 /*
  * This routine switches between two different tasks.  The process
  * state of one is saved on its kernel stack.  Then the state
@@ -528,6 +580,8 @@ _GLOBAL(_switch)
 	std	r23,_CCR(r1)
 	std	r1,KSP(r3)	/* Set old stack pointer */
 
+	FLUSH_COUNT_CACHE
+
 	/*
 	 * On SMP kernels, care must be taken because a task may be
 	 * scheduled off CPUx and on to CPUy. Memory ordering must be