linux/drivers/acpi
Len Brown b430acbd7c ACPICA: simplify SCI_EN workaround
acpi_hw_set_mode() double checks its effectiveness
by calling acpi_hw_get_mode() -- polling up to 3 seconds.

It would be more logical for its caller, acpi_enable()
acpi_enable() to do the double-checking.  (lets assume
that acpi_disable() isn't interesting)

The ACPI specification is unclear on this point.
Some parts say that the BIOS sets SCI_EN and then returns to the OS,
but one part says "OSPM polls the SCI_EN bit until it is sampled SET".

The systems I have on hand do the former,
SCI_EN is observed to be set upon return from the BIOS.

So we move the check up out of acpi_hw_set_mode()
up into acpi_enable() where it makes logical sense.

Then we replace the 3-second polling loop
with a single check.  If this check fails, we'll see:

	"Hardware did not enter ACPI mode"

and the system will bail out of ACPI initialization
and likely fail to boot.  If we see that in practice,
we can restore the polling, but put it into acpi_enable.

This patch is important if acpi_enable() is used in
the resume from S3 path.  Many systems today are seen
coming back from S3 with SCI_EN off, and then failing
to set SCI_EN in response to acpi_enable().  Those systems
will take 3 seconds longer to resume due to this loop.

However, it is possible that we will not use acpi_enable()
in the S3 resume path, and bang SCI_EN directly, which
would make the loop harmless, as it would be invisible
to all systems except those that need it.

Signed-off-by: Len Brown <len.brown@intel.com>
2010-05-12 00:37:59 -04:00
..
acpica ACPICA: simplify SCI_EN workaround 2010-05-12 00:37:59 -04:00
ac.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
acpi_memhotplug.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
acpi_pad.c acpi_pad: "processor_aggregator" name too long 2010-05-06 02:38:23 -04:00
battery.c Merge branches 'battery', 'bugzilla-14667', 'bugzilla-15096', 'bugzilla-15480', 'bugzilla-15521', 'bugzilla-15605', 'gpe-reference-counters', 'misc', 'pxm-fix' and 'video-random-key' into release 2010-04-06 17:06:22 -04:00
blacklist.c ACPI: disable _OSI(Windows 2009) on Asus K50IJ 2009-12-22 02:39:24 -05:00
bus.c ACPI: silence kmemcheck false positive 2010-04-27 03:15:08 -04:00
button.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
cm_sbs.c ACPI: Move definition of PREFIX from acpi_bus.h to internal..h 2009-08-28 19:57:27 -04:00
container.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
debug.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
dock.c Merge branches 'battery', 'bugzilla-14667', 'bugzilla-15096', 'bugzilla-15480', 'bugzilla-15521', 'bugzilla-15605', 'gpe-reference-counters', 'misc', 'pxm-fix' and 'video-random-key' into release 2010-04-06 17:06:22 -04:00
ec.c Merge branches 'battery', 'bugzilla-14667', 'bugzilla-15096', 'bugzilla-15480', 'bugzilla-15521', 'bugzilla-15605', 'gpe-reference-counters', 'misc', 'pxm-fix' and 'video-random-key' into release 2010-04-06 17:06:22 -04:00
event.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
fan.c ACPI: Remove repeated registered as cooling_device messages 2009-12-16 00:07:10 -05:00
glue.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
hest.c ACPI: fix acpi_hest_firmware_first_pci() caused oops 2010-05-06 02:39:06 -04:00
internal.h Merge branches 'battery-2.6.34', 'bugzilla-10805', 'bugzilla-14668', 'bugzilla-531916-power-state', 'ht-warn-2.6.34', 'pnp', 'processor-rename', 'sony-2.6.34', 'suse-bugzilla-531547', 'tz-check', 'video' and 'misc-2.6.34' into release 2010-03-14 21:30:17 -04:00
Kconfig ACPI: Kconfig, fix proc aggregator text 2009-10-09 13:14:51 -04:00
Makefile ACPI: processor: mv processor_pdc.c processor_core.c 2010-03-14 21:17:17 -04:00
numa.c ACPI: NUMA: map pxms to low node ids 2010-04-04 00:50:01 -04:00
osl.c Merge branches 'battery', 'bugzilla-14667', 'bugzilla-15096', 'bugzilla-15480', 'bugzilla-15521', 'bugzilla-15605', 'gpe-reference-counters', 'misc', 'pxm-fix' and 'video-random-key' into release 2010-04-06 17:06:22 -04:00
pci_bind.c PCI / ACPI / PM: Platform support for PCI PME wake-up 2010-02-22 16:21:02 -08:00
pci_irq.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
pci_link.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
pci_root.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
pci_slot.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
power_meter.c power_meter: acpi_device_class "power_meter_resource" too long 2010-05-06 02:38:24 -04:00
power.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
proc.c Fix misspellings of "separate" in strings. 2010-02-04 11:55:46 +01:00
processor_core.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
processor_driver.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
processor_idle.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
processor_perflib.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
processor_thermal.c ACPI: Remove unnecessary cast. 2010-01-15 23:06:44 -05:00
processor_throttling.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
reboot.c ACPI: reboot.c: use new acpi_reset interface 2008-12-31 01:15:00 -05:00
sbs.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
sbshc.c sbshc: acpi_device_class "smbus_host_controller" too long 2010-05-06 02:38:25 -04:00
sbshc.h ACPI: SBS: Ignore alarms coming from unknown devices 2007-12-14 15:14:06 -05:00
scan.c Merge branches 'battery', 'bugzilla-14667', 'bugzilla-15096', 'bugzilla-15480', 'bugzilla-15521', 'bugzilla-15605', 'gpe-reference-counters', 'misc', 'pxm-fix' and 'video-random-key' into release 2010-04-06 17:06:22 -04:00
sleep.c ACPI: sleep: eliminate duplicate entries in acpisleep_dmi_table[] 2010-05-11 10:07:53 -07:00
sleep.h ACPI: convert acpi_device_lock spinlock to mutex 2009-04-07 00:02:40 -04:00
system.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
tables.c ACPI: fix "acpi=ht" boot option 2010-02-18 03:49:38 -05:00
thermal.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
utils.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
video_detect.c Merge branch 'acpica' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 2009-12-09 19:57:06 -08:00
video.c Merge branches 'battery', 'bugzilla-14667', 'bugzilla-15096', 'bugzilla-15480', 'bugzilla-15521', 'bugzilla-15605', 'gpe-reference-counters', 'misc', 'pxm-fix' and 'video-random-key' into release 2010-04-06 17:06:22 -04:00
wakeup.c ACPI / PM: Add more run-time wake-up fields 2010-02-22 16:20:51 -08:00