From 31639c77e0a7f9f742c813ae697f337b44981ed2 Mon Sep 17 00:00:00 2001 From: Suresh Warrier Date: Thu, 17 Dec 2015 14:59:04 -0600 Subject: [PATCH] powerpc/smp: Add smp_muxed_ipi_set_message smp_muxed_ipi_message_pass() invokes smp_ops->cause_ipi, which uses an ioremapped address to access registers on the XICS interrupt controller to cause the IPI. Because of this real mode callers cannot call smp_muxed_ipi_message_pass() for IPI messaging. This patch creates a separate function smp_muxed_ipi_set_message just to set the IPI message without the cause_ipi routine. After calling this function to set the IPI message, real mode callers must cause the IPI by writing to the XICS registers directly. As part of this, we also change smp_muxed_ipi_message_pass to call smp_muxed_ipi_set_message to set the message instead of doing it directly inside the routine. Signed-off-by: Suresh Warrier Acked-by: Michael Ellerman Signed-off-by: Paul Mackerras --- arch/powerpc/include/asm/smp.h | 1 + arch/powerpc/kernel/smp.c | 9 ++++++++- 2 files changed, 9 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/include/asm/smp.h b/arch/powerpc/include/asm/smp.h index 9ef9c37cb398..78083ed20792 100644 --- a/arch/powerpc/include/asm/smp.h +++ b/arch/powerpc/include/asm/smp.h @@ -124,6 +124,7 @@ extern const char *smp_ipi_name[]; /* for irq controllers with only a single ipi */ extern void smp_muxed_ipi_set_data(int cpu, unsigned long data); extern void smp_muxed_ipi_message_pass(int cpu, int msg); +extern void smp_muxed_ipi_set_message(int cpu, int msg); extern irqreturn_t smp_ipi_demux(void); void smp_init_pSeries(void); diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c index a53a13047330..e222efcf6aef 100644 --- a/arch/powerpc/kernel/smp.c +++ b/arch/powerpc/kernel/smp.c @@ -218,7 +218,7 @@ void smp_muxed_ipi_set_data(int cpu, unsigned long data) info->data = data; } -void smp_muxed_ipi_message_pass(int cpu, int msg) +void smp_muxed_ipi_set_message(int cpu, int msg) { struct cpu_messages *info = &per_cpu(ipi_message, cpu); char *message = (char *)&info->messages; @@ -228,6 +228,13 @@ void smp_muxed_ipi_message_pass(int cpu, int msg) */ smp_mb(); message[msg] = 1; +} + +void smp_muxed_ipi_message_pass(int cpu, int msg) +{ + struct cpu_messages *info = &per_cpu(ipi_message, cpu); + + smp_muxed_ipi_set_message(cpu, msg); /* * cause_ipi functions are required to include a full barrier * before doing whatever causes the IPI.