[PATCH 08/17] riscv: improve the default power off implementation

From: Christoph Hellwig
Date: Mon Jun 24 2019 - 01:43:53 EST


Only call the SBI code if we are not running in M mode, and if we didn't
do the SBI call, or it didn't succeed call wfi in a loop to at least
save some power.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
arch/riscv/kernel/reset.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/riscv/kernel/reset.c b/arch/riscv/kernel/reset.c
index d0fe623bfb8f..2f5ca379747e 100644
--- a/arch/riscv/kernel/reset.c
+++ b/arch/riscv/kernel/reset.c
@@ -8,8 +8,11 @@

static void default_power_off(void)
{
+#ifndef CONFIG_M_MODE
sbi_shutdown();
- while (1);
+#endif
+ while (1)
+ wait_for_interrupt();
}

void (*pm_power_off)(void) = default_power_off;
--
2.20.1