[PATCH AUTOSEL 3.18 05/19] MIPS: ath79: fix system restart

From: Sasha Levin
Date: Thu Sep 06 2018 - 20:43:35 EST


From: Felix Fietkau <nbd@xxxxxxxx>

[ Upstream commit f8a7bfe1cb2c1ebfa07775c9c8ac0ad3ba8e5ff5 ]

This patch disables irq on reboot to fix hang issues that were observed
due to pending interrupts.

Signed-off-by: Felix Fietkau <nbd@xxxxxxxx>
Signed-off-by: John Crispin <john@xxxxxxxxxxx>
Signed-off-by: Paul Burton <paul.burton@xxxxxxxx>
Patchwork: https://patchwork.linux-mips.org/patch/19913/
Cc: James Hogan <jhogan@xxxxxxxxxx>
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxx
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
arch/mips/ath79/setup.c | 1 +
arch/mips/include/asm/mach-ath79/ath79.h | 1 +
2 files changed, 2 insertions(+)

diff --git a/arch/mips/ath79/setup.c b/arch/mips/ath79/setup.c
index 64807a4809d0..2b3b66780152 100644
--- a/arch/mips/ath79/setup.c
+++ b/arch/mips/ath79/setup.c
@@ -40,6 +40,7 @@ static char ath79_sys_type[ATH79_SYS_TYPE_LEN];

static void ath79_restart(char *command)
{
+ local_irq_disable();
ath79_device_reset_set(AR71XX_RESET_FULL_CHIP);
for (;;)
if (cpu_wait)
diff --git a/arch/mips/include/asm/mach-ath79/ath79.h b/arch/mips/include/asm/mach-ath79/ath79.h
index 1557934aaca9..39a10a136f53 100644
--- a/arch/mips/include/asm/mach-ath79/ath79.h
+++ b/arch/mips/include/asm/mach-ath79/ath79.h
@@ -132,6 +132,7 @@ static inline u32 ath79_pll_rr(unsigned reg)
static inline void ath79_reset_wr(unsigned reg, u32 val)
{
__raw_writel(val, ath79_reset_base + reg);
+ (void) __raw_readl(ath79_reset_base + reg); /* flush */
}

static inline u32 ath79_reset_rr(unsigned reg)
--
2.17.1