Kevin discovered that commit c8d82ff68f
("ARM: OMAP2/3: hwmod data: Add 32k-sync timer data to hwmod
database") broke CORE idle on OMAP3. This prevents device low power
states.
The root cause is that the 32K sync timer IP block does not support
smart-idle mode[1], and so the hwmod code keeps the IP block in
no-idle mode while it is active. This in turn prevents the WKUP
clockdomain from transitioning to idle. There is a hardcoded sleep
dependency that prevents the CORE_L3 and CORE_CM clockdomains from
transitioning to idle when the WKUP clockdomain is active[2], so the
chip cannot enter any device low power states.
It turns out that there is no need to take the 32k sync timer out of
idle. The IP block itself probably does not have any native idle
handling at all, due to its simplicity. Furthermore, the PRCM will
never request target idle for this IP block while the kernel is
running, due to the sleep dependency that prevents the WKUP
clockdomain from idling while the CORE_L3 clockdomain is active. So
we can safely leave the 32k sync timer in target-force-idle mode, even
while we continue to access it.
This workaround is implemented by defining a new clockdomain flag,
CLKDM_ACTIVE_WITH_MPU, that indicates that the clockdomain is
guaranteed to be active whenever the MPU is inactive. If an IP
block's main functional clock exists inside this clockdomain, and the
IP block does not support smart-idle modes, then the hwmod code will
place the IP block into target force-idle mode even when enabled. The
WKUP clockdomains on OMAP3/4 are marked with this flag. (On OMAP2xxx,
no OCP header existed on the 32k sync timer.) Other clockdomains also
should be marked with this flag, but those changes are deferred until
a later merge window, to create a minimal fix.
Another theoretically clean fix for this problem would be to implement
PM runtime-based control for 32k sync timer accesses. These PM
runtime calls would need to located in a custom clocksource, since the
32k sync timer is currently used as an MMIO clocksource. But in
practice, there would be little benefit to doing so; and there would
be some cost, due to the addition of unnecessary lines of code and the
additional CPU overhead of the PM runtime and hwmod code - unnecessary
in this case.
Another possible fix would have been to modify the pm34xx.c code to
force the IP block idle before entering WFI. But this would not have
been an acceptable approach: we are trying to remove this type of
centralized IP block idle control from the PM code.
This patch is a collaboration between Kevin Hilman <khilman@ti.com>
and Paul Walmsley <paul@pwsan.com>.
Thanks to Vaibhav Hiremath <hvaibhav@ti.com> for providing comments on
an earlier version of this patch. Thanks to Tero Kristo
<t-kristo@ti.com> for identifying a bug in an earlier version of this
patch. Thanks to Benoît Cousson <b-cousson@ti.com> for identifying
some bugs in several versions of this patch and for implementation
comments.
References:
1. Table 16-96 "REG_32KSYNCNT_SYSCONFIG" of the OMAP34xx TRM Rev. ZU
(SWPU223U), available from:
http://www.ti.com/pdfs/wtbu/OMAP34x_ES3.1.x_PUBLIC_TRM_vzU.zip
2. Table 4-72 "Sleep Dependencies" of the OMAP34xx TRM Rev. ZU
(SWPU223U)
3. ibid.
Cc: Tony Lindgren <tony@atomide.com>
Cc: Vaibhav Hiremath <hvaibhav@ti.com>
Cc: Benoît Cousson <b-cousson@ti.com>
Cc: Tero Kristo <t-kristo@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
The PRM and CM implicit clockdomains will soon be used by OMAP44xx.
So, make them common to OMAP2+ and modify the OMAP4 clockdomains code
so use of these clockdomains doesn't crash the system.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Rajendra Nayak <rnayak@ti.com>
At Tony's request, remove the omap_chip bitmasks from the clockdomain
and clockdomain dependency definitions. Instead, initialize
clockdomains based on one or more lists that are applicable to a
particular SoC family, variant, and silicon revision.
Tony Lindgren <tony@atomide.com> found a bug in a previous version of this
patch - thanks Tony.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Tony Lindgren <tony@atomide.com>
In preparation for OMAP_CHIP() removal, split clkdm_init() into four
functions. This allows some of them to be called multiple times: for
example, clkdm_register_clkdms() can be called once to register
clockdomains that are common to a group of SoCs, and once to register
clockdomains that are specific to a single SoC.
The appropriate order to call these functions - which is enforced
by the code - is:
1. clkdm_register_platform_funcs()
2. clkdm_register_clkdms() (can be called multiple times)
3. clkdm_register_autodeps() (optional; deprecated)
4. clkdm_complete_init()
Convert the OMAP2, 3, and 4 clockdomain init code to use these new
functions.
While here, improve documentation, and increase CodingStyle
conformance by shortening some local variable names.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
This patch fixes these warnings when building kernel for OMAP3EVM
only.
CC arch/arm/mach-omap2/clockdomains2xxx_3xxx_data.o
arch/arm/mach-omap2/clockdomains2xxx_3xxx_data.c:95: warning:
'dsp_24xx_wkdeps' defined but not used
arch/arm/mach-omap2/clockdomains2xxx_3xxx_data.c:119: warning:
'mpu_24xx_wkdeps' defined but not used
arch/arm/mach-omap2/clockdomains2xxx_3xxx_data.c:147: warning:
'core_24xx_wkdeps' defined but not used
The problem should be noticed when building for other OMAP3
platforms (only) as well.
Signed-off-by: Sanjeev Premi <premi@ti.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Define the following architecture specific funtions for omap2/3
.clkdm_add_wkdep
.clkdm_del_wkdep
.clkdm_read_wkdep
.clkdm_clear_all_wkdeps
.clkdm_add_sleepdep
.clkdm_del_sleepdep
.clkdm_read_sleepdep
.clkdm_clear_all_sleepdeps
Convert the platform-independent framework to call these functions.
With this also move the clkdm lookups for all wkdep_srcs and
sleepdep_srcs at clkdm_init.
Signed-off-by: Rajendra Nayak <rnayak@ti.com>
[paul@pwsan.com: fixed loop termination conditions in omap*_clkdm_clear_all_*();
thanks to Kevin Hilman for finding and helping fix those bugs; also
avoid re-resolving clockdomains during init; abstracted out clkdm_dep walk]
Cc: Kevin Hilman <khilman@ti.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Put infrastructure in place, so arch specific func pointers
can be hooked up to the platform-independent part of the
framework.
This is in preparation of splitting the clockdomain framework into
platform-independent part (for all omaps) and platform-specific
parts.
Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
We want to have just CONFIG_ARCH_OMAP2, 3 and 4. The rest
are nowadays just subcategories of these.
Search and replace the following:
ARCH_OMAP2420 SOC_OMAP2420
ARCH_OMAP2430 SOC_OMAP2430
ARCH_OMAP3430 SOC_OMAP3430
No functional changes.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Thomas Weber <weber@corscience.de>
Acked-by: Sourav Poddar <sourav.poddar@ti.com>
The OMAP clockdomain code and data is all OMAP2+-specific. This seems
unlikely to change any time soon. Move plat-omap/include/plat/clockdomain.h
to mach-omap2/clockdomain.h. The primary point of doing this is to remove
the temptation for unrelated upper-layer code to access clockdomain code
and data directly.
DSPBridge also uses the clockdomain headers for some reason, so,
modify it also. The DSPBridge code should not be including the
clockdomain headers; these should be removed.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@deeprootsystems.com>
Cc: Omar Ramirez Luna <omar.ramirez@ti.com>
Cc: Felipe Contreras <felipe.contreras@gmail.com>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Tested-by: Rajendra Nayak <rnayak@ti.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reverse some of the effects of commit
84c0c39aec ("ARM: OMAP4: PM: Make OMAP3
Clock-domain framework compatible for OMAP4"). On OMAP2/3, the
CM_CLKSTCTRL register is at a constant offset from the powerdomain's
CM instance.
Also, remove some of the direct CM register access from the
clockdomain code, moving it to the OMAP2/3 CM code instead. The
intention here is to simplify the clockdomain code. (The long-term
goal is to move all direct CM register access across the OMAP core
code to the appropriate cm*.c file.)
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Tested-by: Rajendra Nayak <rnayak@ti.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
In preparation for adding OMAP4-specific PRCM accessor/mutator
functions, split the existing OMAP2/3 PRCM code into OMAP2/3-specific
files. Most of what was in mach-omap2/{cm,prm}.{c,h} has now been
moved into mach-omap2/{cm,prm}2xxx_3xxx.{c,h}, since it was
OMAP2xxx/3xxx-specific.
This process also requires the #includes in each of these files to be
changed to reference the new file name. As part of doing so, add some
comments into plat-omap/sram.c and plat-omap/mcbsp.c, which use
"sideways includes", to indicate that these users of the PRM/CM includes
should not be doing so.
Thanks to Felipe Contreras <felipe.contreras@gmail.com> for comments on this
patch.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Jarkko Nikula <jhnikula@gmail.com>
Cc: Peter Ujfalusi <peter.ujfalusi@nokia.com>
Cc: Liam Girdwood <lrg@slimlogic.co.uk>
Cc: Omar Ramirez Luna <omar.ramirez@ti.com>
Acked-by: Omar Ramirez Luna <omar.ramirez@ti.com>
Cc: Felipe Contreras <felipe.contreras@gmail.com>
Acked-by: Felipe Contreras <felipe.contreras@gmail.com>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Reviewed-by: Kevin Hilman <khilman@deeprootsystems.com>
Tested-by: Kevin Hilman <khilman@deeprootsystems.com>
Tested-by: Rajendra Nayak <rnayak@ti.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Static data should be declared in .c files, not .h files. It should be
possible to #include .h files at any point without creating multiple
copies of the same data.
We converted the clock data to .c files some time ago. This patch does
the same for the clockdomain data.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Reviewed-by: Kevin Hilman <khilman@deeprootsystems.com>
Tested-by: Kevin Hilman <khilman@deeprootsystems.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Rajendra Nayak <rnayak@ti.com>
