path: root/arch/arm/mach-realview/platsmp.c
diff options
authorStephen Boyd <sboyd@codeaurora.org>2011-07-07 01:56:51 +0100
committerRussell King <rmk+kernel@arm.linux.org.uk>2011-07-07 14:45:07 +0100
commit7fa22bd5460bb2021729fa5a1012c60b9b3a56e2 (patch)
treef17dd732f1c915b52a3d5de968ed0e26596a4feb /arch/arm/mach-realview/platsmp.c
parent10cdc7e5129ac26aefece4c7a7d5b1a0285237c2 (diff)
ARM: 6993/1: platsmp: Allow secondary cpu hotplug with maxcpus=1
If an ARM system has multiple cpus in the same socket and the kernel is booted with maxcpus=1, secondary cpus are possible but not present due to how platform_smp_prepare_cpus() is called. Since most typical ARM processors don't actually support physical hotplug, initialize the present map to be equal to the possible map in generic ARM SMP code. Also, always call platform_smp_prepare_cpus() as long as max_cpus is non-zero (0 means no SMP) to allow platform code to do any SMP setup. After applying this patch it's possible to boot an ARM system with maxcpus=1 on the command line and then hotplug in secondary cpus via sysfs. This is more in line with how x86 does things. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Kukjin Kim <kgene.kim@samsung.com> Cc: David Brown <davidb@codeaurora.org> Cc: Tony Lindgren <tony@atomide.com> Cc: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com> Cc: Linus Walleij <linus.walleij@stericsson.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/mach-realview/platsmp.c')
1 files changed, 0 insertions, 8 deletions
diff --git a/arch/arm/mach-realview/platsmp.c b/arch/arm/mach-realview/platsmp.c
index 963bf0d8119..4ae943bafa9 100644
--- a/arch/arm/mach-realview/platsmp.c
+++ b/arch/arm/mach-realview/platsmp.c
@@ -68,14 +68,6 @@ void __init smp_init_cpus(void)
void __init platform_smp_prepare_cpus(unsigned int max_cpus)
- int i;
- /*
- * Initialise the present map, which describes the set of CPUs
- * actually populated at the present time.
- */
- for (i = 0; i < max_cpus; i++)
- set_cpu_present(i, true);