linux/arch/arm/mach-realview
Stephen Boyd 7fa22bd546 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>
2011-07-07 14:45:07 +01:00
..
include/mach Merge branches 'consolidate-clksrc', 'consolidate-flash', 'consolidate-generic', 'consolidate-smp', 'consolidate-stmp' and 'consolidate-zones' into consolidate 2011-05-23 18:05:10 +01:00
Kconfig ARM: 6986/1: mach-realview: add TCM support for PB1176 2011-07-06 20:49:45 +01:00
Makefile ARM: realview/vexpress: consolidate SMP bringup code 2011-02-19 11:11:41 +00:00
Makefile.boot RealView: Allow PHYS_OFFSET at 0x70000000 2008-12-01 14:54:55 +00:00
core.c Merge branches 'consolidate-clksrc', 'consolidate-flash', 'consolidate-generic', 'consolidate-smp', 'consolidate-stmp' and 'consolidate-zones' into consolidate 2011-05-23 18:05:10 +01:00
core.h ARM: realview: remove old AMBA device DMA definitions 2011-02-19 11:11:24 +00:00
hotplug.c ARM: CPU hotplug: fix hard-coded control register constants 2010-12-20 15:09:16 +00:00
platsmp.c ARM: 6993/1: platsmp: Allow secondary cpu hotplug with maxcpus=1 2011-07-07 14:45:07 +01:00
realview_eb.c ARM: 6807/1: realview: Fix secondary GIC initialisation for EB with MPCore tile 2011-03-26 10:06:08 +00:00
realview_pb11mp.c Merge branches 'fixes', 'pgt-next' and 'versatile' into devel 2011-03-20 09:32:12 +00:00
realview_pb1176.c Merge branches 'fixes', 'pgt-next' and 'versatile' into devel 2011-03-20 09:32:12 +00:00
realview_pba8.c Merge branches 'fixes', 'pgt-next' and 'versatile' into devel 2011-03-20 09:32:12 +00:00
realview_pbx.c Merge branches 'fixes', 'pgt-next' and 'versatile' into devel 2011-03-20 09:32:12 +00:00