Patch "powerpc: Set missing wakeup bit in LPCR on POWER9" has been added to the 4.8-stable tree

Patch "powerpc: Set missing wakeup bit in LPCR on POWER9" has been added to the 4.8-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    powerpc: Set missing wakeup bit in LPCR on POWER9

to the 4.8-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     powerpc-set-missing-wakeup-bit-in-lpcr-on-power9.patch
and it can be found in the queue-4.8 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 7a43906f5cbfb74712af168988455e350707e310 Mon Sep 17 00:00:00 2001
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Mon, 21 Nov 2016 18:08:05 +1100
Subject: powerpc: Set missing wakeup bit in LPCR on POWER9

From: Benjamin Herrenschmidt <benh@kernel.crashing.org>

commit 7a43906f5cbfb74712af168988455e350707e310 upstream.

There is a new bit, LPCR_PECE_HVEE (Hypervisor Virtualization Exit
Enable), which controls wakeup from STOP states on Hypervisor
Virtualization Interrupts (which happen to also be all external
interrupts in host or bare metal mode).

It needs to be set or we will miss wakeups.

Fixes: 9baaef0a22c8 ("powerpc/irq: Add support for HV virtualization interrupts")
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[mpe: Rename it to HVEE to match the name in the ISA]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/powerpc/include/asm/reg.h        |    1 +
 arch/powerpc/kernel/cpu_setup_power.S |    8 ++++----
 2 files changed, 5 insertions(+), 4 deletions(-)

--- 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 */
--- 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


Patches currently in stable-queue which might be from benh@kernel.crashing.org are

queue-4.8/powerpc-set-missing-wakeup-bit-in-lpcr-on-power9.patch