8 files changed, 52 insertions, 12 deletions

diff --git a/arch/powerpc/boot/main.c b/arch/powerpc/boot/main.c
index d80161b63..60522d22a 100644
--- a/arch/powerpc/boot/main.c
+++ b/arch/powerpc/boot/main.c
@@ -217,8 +217,12 @@ void start(void)
 		console_ops.close();
 
 	kentry = (kernel_entry_t) vmlinux.addr;
-	if (ft_addr)
-		kentry(ft_addr, 0, NULL);
+	if (ft_addr) {
+		if(platform_ops.kentry)
+			platform_ops.kentry(ft_addr, vmlinux.addr);
+		else
+			kentry(ft_addr, 0, NULL);
+	}
 	else
 		kentry((unsigned long)initrd.addr, initrd.size,
 		       loader_info.promptr);
diff --git a/arch/powerpc/boot/opal-calls.S b/arch/powerpc/boot/opal-calls.S
index ff2f1b97b..2a99fc9a3 100644
--- a/arch/powerpc/boot/opal-calls.S
+++ b/arch/powerpc/boot/opal-calls.S
@@ -12,6 +12,19 @@
 
 	.text
 
+	.globl opal_kentry
+opal_kentry:
+	/* r3 is the fdt ptr */
+	mtctr r4
+	li	r4, 0
+	li	r5, 0
+	li	r6, 0
+	li	r7, 0
+	ld	r11,opal@got(r2)
+	ld	r8,0(r11)
+	ld	r9,8(r11)
+	bctr
+
 #define OPAL_CALL(name, token)				\
 	.globl name;					\
 name:							\
diff --git a/arch/powerpc/boot/opal.c b/arch/powerpc/boot/opal.c
index 1f37e1c1d..d7b4fd47e 100644
--- a/arch/powerpc/boot/opal.c
+++ b/arch/powerpc/boot/opal.c
@@ -23,14 +23,25 @@ struct opal {
 
 static u32 opal_con_id;
 
+/* see opal-wrappers.S */
 int64_t opal_console_write(int64_t term_number, u64 *length, const u8 *buffer);
 int64_t opal_console_read(int64_t term_number, uint64_t *length, u8 *buffer);
 int64_t opal_console_write_buffer_space(uint64_t term_number, uint64_t *length);
 int64_t opal_console_flush(uint64_t term_number);
 int64_t opal_poll_events(uint64_t *outstanding_event_mask);
 
+void opal_kentry(unsigned long fdt_addr, void *vmlinux_addr);
+
 static int opal_con_open(void)
 {
+	/*
+	 * When OPAL loads the boot kernel it stashes the OPAL base and entry
+	 * address in r8 and r9 so the kernel can use the OPAL console
+	 * before unflattening the devicetree. While executing the wrapper will
+	 * probably trash r8 and r9 so this kentry hook restores them before
+	 * entering the decompressed kernel.
+	 */
+	platform_ops.kentry = opal_kentry;
 	return 0;
 }
 
diff --git a/arch/powerpc/boot/ops.h b/arch/powerpc/boot/ops.h
index e19b64ef9..deeae6f6b 100644
--- a/arch/powerpc/boot/ops.h
+++ b/arch/powerpc/boot/ops.h
@@ -30,6 +30,7 @@ struct platform_ops {
 	void *	(*realloc)(void *ptr, unsigned long size);
 	void	(*exit)(void);
 	void *	(*vmlinux_alloc)(unsigned long size);
+	void  	(*kentry)(unsigned long fdt_addr, void *vmlinux_addr);
 };
 extern struct platform_ops platform_ops;
 
diff --git a/arch/powerpc/include/asm/mmu.h b/arch/powerpc/include/asm/mmu.h
index e2fb408f8..fd10b582f 100644
--- a/arch/powerpc/include/asm/mmu.h
+++ b/arch/powerpc/include/asm/mmu.h
@@ -29,6 +29,12 @@
  */
 
 /*
+ * Kernel read only support.
+ * We added the ppp value 0b110 in ISA 2.04.
+ */
+#define MMU_FTR_KERNEL_RO		ASM_CONST(0x00004000)
+
+/*
  * We need to clear top 16bits of va (from the remaining 64 bits )in
  * tlbie* instructions
  */
@@ -103,10 +109,10 @@
 #define MMU_FTRS_POWER4		MMU_FTRS_DEFAULT_HPTE_ARCH_V2
 #define MMU_FTRS_PPC970		MMU_FTRS_POWER4 | MMU_FTR_TLBIE_CROP_VA
 #define MMU_FTRS_POWER5		MMU_FTRS_POWER4 | MMU_FTR_LOCKLESS_TLBIE
-#define MMU_FTRS_POWER6		MMU_FTRS_POWER4 | MMU_FTR_LOCKLESS_TLBIE
-#define MMU_FTRS_POWER7		MMU_FTRS_POWER4 | MMU_FTR_LOCKLESS_TLBIE
-#define MMU_FTRS_POWER8		MMU_FTRS_POWER4 | MMU_FTR_LOCKLESS_TLBIE
-#define MMU_FTRS_POWER9		MMU_FTRS_POWER4 | MMU_FTR_LOCKLESS_TLBIE
+#define MMU_FTRS_POWER6		MMU_FTRS_POWER4 | MMU_FTR_LOCKLESS_TLBIE | MMU_FTR_KERNEL_RO
+#define MMU_FTRS_POWER7		MMU_FTRS_POWER4 | MMU_FTR_LOCKLESS_TLBIE | MMU_FTR_KERNEL_RO
+#define MMU_FTRS_POWER8		MMU_FTRS_POWER4 | MMU_FTR_LOCKLESS_TLBIE | MMU_FTR_KERNEL_RO
+#define MMU_FTRS_POWER9		MMU_FTRS_POWER4 | MMU_FTR_LOCKLESS_TLBIE | MMU_FTR_KERNEL_RO
 #define MMU_FTRS_CELL		MMU_FTRS_DEFAULT_HPTE_ARCH_V2 | \
 				MMU_FTR_CI_LARGE_PAGE
 #define MMU_FTRS_PA6T		MMU_FTRS_DEFAULT_HPTE_ARCH_V2 | \
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index 978dada66..52cbf043e 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -355,6 +355,7 @@
 #define     LPCR_PECE0		ASM_CONST(0x0000000000004000)	/* ext. exceptions can cause exit */
 #define     LPCR_PECE1		ASM_CONST(0x0000000000002000)	/* decrementer can cause exit */
 #define     LPCR_PECE2		ASM_CONST(0x0000000000001000)	/* machine check etc can cause exit */
+#define     LPCR_PECE_HVEE	ASM_CONST(0x0000400000000000)	/* P9 Wakeup on HV interrupts */
 #define   LPCR_MER		ASM_CONST(0x0000000000000800)	/* Mediated External Exception */
 #define   LPCR_MER_SH		11
 #define   LPCR_TC		ASM_CONST(0x0000000000000200)	/* Translation control */
diff --git a/arch/powerpc/kernel/cpu_setup_power.S b/arch/powerpc/kernel/cpu_setup_power.S
index 52ff3f025..37c027ca8 100644
--- a/arch/powerpc/kernel/cpu_setup_power.S
+++ b/arch/powerpc/kernel/cpu_setup_power.S
@@ -98,8 +98,8 @@ _GLOBAL(__setup_cpu_power9)
 	li	r0,0
 	mtspr	SPRN_LPID,r0
 	mfspr	r3,SPRN_LPCR
-	ori	r3, r3, LPCR_PECEDH
-	ori	r3, r3, LPCR_HVICE
+	LOAD_REG_IMMEDIATE(r4, LPCR_PECEDH | LPCR_PECE_HVEE | LPCR_HVICE)
+	or	r3, r3, r4
 	bl	__init_LPCR
 	bl	__init_HFSCR
 	bl	__init_tlb_power9
@@ -118,8 +118,8 @@ _GLOBAL(__restore_cpu_power9)
 	li	r0,0
 	mtspr	SPRN_LPID,r0
 	mfspr   r3,SPRN_LPCR
-	ori	r3, r3, LPCR_PECEDH
-	ori	r3, r3, LPCR_HVICE
+	LOAD_REG_IMMEDIATE(r4, LPCR_PECEDH | LPCR_PECE_HVEE | LPCR_HVICE)
+	or	r3, r3, r4
 	bl	__init_LPCR
 	bl	__init_HFSCR
 	bl	__init_tlb_power9
diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index 28923b2e2..8dff9ce6f 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -190,8 +190,12 @@ unsigned long htab_convert_pte_flags(unsigned long pteflags)
 		/*
 		 * Kernel read only mapped with ppp bits 0b110
 		 */
-		if (!(pteflags & _PAGE_WRITE))
-			rflags |= (HPTE_R_PP0 | 0x2);
+		if (!(pteflags & _PAGE_WRITE)) {
+			if (mmu_has_feature(MMU_FTR_KERNEL_RO))
+				rflags |= (HPTE_R_PP0 | 0x2);
+			else
+				rflags |= 0x3;
+		}
 	} else {
 		if (pteflags & _PAGE_RWX)
 			rflags |= 0x2;