MIPS: kexec: Make a framework for both jumping and halting on nonboot CPUs

The existing implementation lets machine_kexec() CPU jump to reboot code
buffer, whereas other CPUs to relocated_kexec_smp_wait. The natural way to
bring up an SMP new kernel would be to let CPU0 do it while others being
halted. For those failing to do so, fall back to the jumping method.

Signed-off-by: Dengcheng Zhu <dzhu@wavecomp.com>
[paul.burton@mips.com: Guard kexec_nonboot_cpu_jump with CONFIG_SMP]
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/20570/
Cc: pburton@wavecomp.com
Cc: ralf@linux-mips.org
Cc: linux-mips@linux-mips.org
Cc: rachel.mozes@intel.com

1 files changed, 16 insertions, 0 deletions

diff --git a/arch/mips/include/asm/smp.h b/arch/mips/include/asm/smp.h
index 056a6bf13491..7990c1c70471 100644
--- a/arch/mips/include/asm/smp.h
+++ b/arch/mips/include/asm/smp.h
@@ -91,6 +91,22 @@ static inline void __cpu_die(unsigned int cpu)
 extern void play_dead(void);
 #endif
 
+#ifdef CONFIG_KEXEC
+static inline void kexec_nonboot_cpu(void)
+{
+	extern const struct plat_smp_ops *mp_ops;	/* private */
+
+	return mp_ops->kexec_nonboot_cpu();
+}
+
+static inline void *kexec_nonboot_cpu_func(void)
+{
+	extern const struct plat_smp_ops *mp_ops;	/* private */
+
+	return mp_ops->kexec_nonboot_cpu;
+}
+#endif
+
 /*
  * This function will set up the necessary IPIs for Linux to communicate
  * with the CPUs in mask.