linux/arch
Nishanth Menon e13d8f3839 OMAP3+: SR: ensure pm-runtime callbacks can be invoked with IRQs disabled
SmartReflex should be disabled while entering low power mode due to
a) SmartReflex values are not defined for retention voltage, further
b) with SmartReflex enabled, if CPU enters lower c-states, FSM will try
to bump the voltage to current OPP's voltage for which it has entered c-state;
hence SmartReflex needs to be disabled for MPU, CORE and IVA voltage
domains in idle path before enabling auto retention voltage achievement
on the device.

However, since the current pm_runtime setup for SmartReflex devices are
setup to allow callbacks to be invoked with interrupts enabled, calling
SmartReflex enable/disable from other contexts such as idle paths
where preemption is disabled causes warnings such as the following
indicating of a potential race.
[   82.023895] [<c04d079c>] (__irq_svc+0x3c/0x120) from [<c04d0484>] (_raw_spin_unlock_irq+0x28/0x2c)
[   82.023895] [<c04d0484>] (_raw_spin_unlock_irq+0x28/0x2c) from [<c0323234>] (rpm_callback+0x4c/0x68)
[   82.023956] [<c0323234>] (rpm_callback+0x4c/0x68) from [<c0323f7c>] (rpm_resume+0x338/0x53c)
[   82.023956] [<c0323f7c>] (rpm_resume+0x338/0x53c) from [<c03243f4>] (__pm_runtime_resume+0x48/0x60)
[   82.023986] [<c03243f4>] (__pm_runtime_resume+0x48/0x60) from [<c008aee0>] (sr_enable+0xa8/0x19c)
[   82.023986] [<c008aee0>] (sr_enable+0xa8/0x19c) from [<c008b2fc>] (omap_sr_enable+0x50/0x90)
[   82.024017] [<c008b2fc>] (omap_sr_enable+0x50/0x90) from [<c00888c0>] (omap4_enter_sleep+0x138/0x168)

Instead, we use pm_runtime_irq_safe to tell the PM core that callbacks can be
invoked in interrupt disabled contexts.

Acked-by: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
[khilman@ti.com: minor changelog edits]
Signed-off-by: Kevin Hilman <khilman@ti.com>
2011-08-05 11:54:55 -07:00
..
alpha Merge branch 'apei' into apei-release 2011-08-03 11:30:42 -04:00
arm OMAP3+: SR: ensure pm-runtime callbacks can be invoked with IRQs disabled 2011-08-05 11:54:55 -07:00
avr32 Merge branch 'apei' into apei-release 2011-08-03 11:30:42 -04:00
blackfin atomic: cleanup asm-generic atomic*.h inclusion 2011-07-26 16:49:47 -07:00
cris cris: add missing declaration of kgdb_init() and breakpoint() 2011-08-03 14:25:22 -10:00
frv Merge branch 'apei' into apei-release 2011-08-03 11:30:42 -04:00
h8300 atomic: cleanup asm-generic atomic*.h inclusion 2011-07-26 16:49:47 -07:00
ia64 Merge branch 'apei' into apei-release 2011-08-03 11:30:42 -04:00
m32r atomic: cleanup asm-generic atomic*.h inclusion 2011-07-26 16:49:47 -07:00
m68k Merge branch 'apei' into apei-release 2011-08-03 11:30:42 -04:00
microblaze Merge branch 'next' of git://git.monstr.eu/linux-2.6-microblaze 2011-07-27 09:24:20 -07:00
mips atomic: cleanup asm-generic atomic*.h inclusion 2011-07-26 16:49:47 -07:00
mn10300 atomic: cleanup asm-generic atomic*.h inclusion 2011-07-26 16:49:47 -07:00
openrisc OpenRISC: Miscellaneous 2011-07-22 18:46:41 +02:00
parisc Merge branch 'apei' into apei-release 2011-08-03 11:30:42 -04:00
powerpc Merge branch 'apei' into apei-release 2011-08-03 11:30:42 -04:00
s390 Merge branch 'apei' into apei-release 2011-08-03 11:30:42 -04:00
score modules: make arch's use default loader hooks 2011-07-24 22:06:04 +09:30
sh Merge branch 'idle-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6 2011-08-03 21:54:15 -10:00
sparc Merge branch 'apei' into apei-release 2011-08-03 11:30:42 -04:00
tile Merge branch 'apei-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 2011-08-03 21:53:27 -10:00
um ptrace: unify show_regs() prototype 2011-07-26 16:49:43 -07:00
unicore32 Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6 2011-07-29 23:35:05 -07:00
x86 x86: don't include xen/xen.h in <asm/io.h> unless XEN is enabled 2011-08-03 22:00:38 -10:00
xtensa atomic: cleanup asm-generic atomic*.h inclusion 2011-07-26 16:49:47 -07:00
.gitignore
Kconfig Add Kconfig option ARCH_HAVE_NMI_SAFE_CMPXCHG 2011-08-03 11:12:37 -04:00