The __omap_dm_timer_set_source() function is only used by the system timer
(clock-events and clock-source) code for OMAP2+ devices. Therefore, we can
remove this code from the dmtimer driver and move it to the system timer
code for OMAP2+ devices.
The current __omap_dm_timer_set_source() function calls clk_disable() before
calling clk_set_parent() and clk_enable() afterwards. We can avoid these calls
to clk_disable/enable by moving the calls to omap_hwmod_setup_one() and
omap_hwmod_enable() to after the call to clk_set_parent() in
omap_dm_timer_init_one().
The function omap_hwmod_setup_one() will enable the timers functional clock
and therefore increment the use-count of the functional clock to 1.
clk_set_parent() will fail if the use-count is not 0 when called. Hence, if
omap_hwmod_setup_one() is called before clk_set_parent(), we will need to call
clk_disable() before calling clk_set_parent() to decrement the use-count.
Hence, avoid these extra calls to disable and enable the functional clock by
moving the calls to omap_hwmod_setup_one() and omap_hwmod_enable() to after
clk_set_parent().
We can also remove the delay from the __omap_dm_timer_set_source() function
because enabling the clock will now be handled via the HWMOD framework by
calling omap_hwmod_setup_one(). Therefore, by moving the calls to
omap_hwmod_setup_one() and omap_hwmod_enable() to after the call to
clk_set_parent(), we can simply replace __omap_dm_timer_set_source() with
clk_set_parent().
It should be safe to move these hwmod calls to later in the
omap_dm_timer_init_one() because other calls to the hwmod layer that occur
before are just requesting resource information.
Testing includes boot testing on OMAP2420 H4, OMAP3430 SDP and OMAP4430 Blaze
with the following configurations:
1. CONFIG_OMAP_32K_TIMER=y
2. CONFIG_OMAP_32K_TIMER=y and boot parameter "clocksource=gp_timer"
3. CONFIG_OMAP_32K_TIMER not set
4. CONFIG_OMAP_32K_TIMER not set and boot parameter "clocksource=gp_timer"
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Whenever we call the function omap_dm_timer_set_source() to set the clock
source of a dmtimer we look-up the dmtimer functional clock source by
calling clk_get(). This is not necessary because on requesting a dmtimer
we look-up the functional clock source and store it in the omap_dm_timer
structure. So instead of looking up the clock again used the clock handle
that stored in the omap_dm_timer structure.
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
The OMAP dmtimer driver does not currently have a function to disable the
timer interrupts. For some timer instances the timer interrupt enable
function can be used to disable the interrupts because the same interrupt
enable register is used to disable interrupts. However, some timer instances
have separate interrupt enable/disable registers and so this will not work.
Therefore, add a dedicated function to disable interrupts.
This change is required for OMAP4+ devices. For OMAP4, all timers apart from 1,
2 and 10 need this function and for OMAP5 all timers need this function.
Please note that the interrupt disable function has been written so that it
can be used by all OMAP devices.
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
The OMAP DMTIMERs can generate an interrupt when the timer counter value
matches the value stored in the timer's match register. When using this
feature spurious interrupts were seen, because the compare logic is being
enabled before the match value is loaded and according to the documentation
the match value must be loaded before the compare logic is enable.
The reset value for the timer counter and match registers is 0 and hence,
by enabling the compare logic before the actual match value is loaded a
spurious interrupt can be generated as the reset values match.
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Restoring the timer interrupt status is not possible because writing a 1 to any
bit in the register clears that bit if set and writing a 0 has no affect.
Furthermore, if an interrupt is pending when someone attempts to disable a
timer, the timer will fail to transition to the idle state and hence it's
context will not be lost. Users should take care to service all interrupts
before disabling the timer.
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
The timer TISTAT register is a read-only register and therefore restoring the
context is not needed. Furthermore, the context of TISTAT is never saved
anywhere in the current code. The TISTAT register is read-only for all OMAP
devices from OMAP1 to OMAP4. OMAP5 timers no longer have this register.
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
In commit e32f7ec2 (ARM: OMAP: Fix 32 kHz timer and modify GP timer to use GPT1)
a fix was added to prevent timer1 being reset in the function
omap_dm_timer_reset() because timer1 was being used as the system timer for
OMAP2 devices. Although timer1 is still used by most OMAP2+ devices as a system
timer, the function omap_dm_timer_reset() is now only being called for OMAP1
devices and OMAP1 does not use timer1 as a system timer. Therefore, remove the
check in omap_dm_timer_reset() so that timer1 is reset for OMAP1 devices.
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Currently the dmtimer posted mode is being enabled when the function
omap_dm_timer_enable_posted() is called. This function is only being called
for OMAP1 timers and OMAP2+ timers that are being used as system timers. Hence,
for OMAP2+ timers that are NOT being used as a system timer, posted mode is
not enabled but the "timer->posted" variable is still set (incorrectly) in
the omap_dm_timer_prepare() function.
This is a regression introduced by commit 3392cdd3 (ARM: OMAP: dmtimer:
switch-over to platform device driver) which was before the
omap_dm_timer_enable_posted() function was introduced. Although this is a
regression from the original code it only impacts performance and so is not
needed for stable.
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Errata Titles:
i103: Delay needed to read some GP timer, WD timer and sync timer
registers after wakeup (OMAP3/4)
i767: Delay needed to read some GP timer registers after wakeup (OMAP5)
Description (i103/i767):
If a General Purpose Timer (GPTimer) is in posted mode
(TSICR [2].POSTED=1), due to internal resynchronizations, values read in
TCRR, TCAR1 and TCAR2 registers right after the timer interface clock
(L4) goes from stopped to active may not return the expected values. The
most common event leading to this situation occurs upon wake up from
idle.
GPTimer non-posted synchronization mode is not impacted by this
limitation.
Workarounds:
1). Disable posted mode
2). Use static dependency between timer clock domain and MPUSS clock
domain
3). Use no-idle mode when the timer is active
Workarounds #2 and #3 are not pratical from a power standpoint and so
workaround #1 has been implemented. Disabling posted mode adds some CPU
overhead for configuring and reading the timers as the CPU has to wait
for accesses to be re-synchronised within the timer. However, disabling
posted mode guarantees correct operation.
Please note that it is safe to use posted mode for timers if the counter
(TCRR) and capture (TCARx) registers will never be read. An example of
this is the clock-event system timer. This is used by the kernel to
schedule events however, the timers counter is never read and capture
registers are not used. Given that the kernel configures this timer
often yet never reads the counter register it is safe to enable posted
mode in this case. Hence, for the timer used for kernel clock-events,
posted mode is enabled by overriding the errata for devices that are
impacted by this defect.
For drivers using the timers that do not read the counter or capture
registers and wish to use posted mode, can override the errata and
enable posted mode by making the following function calls.
__omap_dm_timer_override_errata(timer, OMAP_TIMER_ERRATA_I103_I767);
__omap_dm_timer_enable_posted(timer);
Both dmtimers and watchdogs are impacted by this defect this patch only
implements the workaround for the dmtimer. Currently the watchdog driver
does not read the counter register and so no workaround is necessary.
Posted mode will be disabled for all OMAP2+ devices (including AM33xx)
using a GP timer as a clock-source timer to guarantee correct operation.
This is not necessary for OMAP24xx devices but the default clock-source
timer for OMAP24xx devices is the 32k-sync timer and not the GP timer
and so should not have any impact. This should be re-visited for future
devices if this errata is fixed.
Confirmed with Vaibhav Hiremath that this bug also impacts AM33xx
devices.
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
For OMAP2+ devices, when using DMTIMERs for system timers (clock-events and
clock-source) the posted mode configuration of the timers is used. To allow
the compiler to optimise the functions for configuring and reading the system
timers, the posted flag variable is hard-coded with the value 1. To make it
clear that posted mode is being used add some definitions so that it is more
readable.
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
From Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>:
arm: at91: mach header cleanup
This first patch serie start the cleanup of the header in mach
by moving all the platform data to include/linux/platform_data
and move the board header and drivers header next to them
* tag 'for-3.8-at91_header_clean' of git://github.com/at91linux/linux-at91:
arm: at91: move at91rm9200 rtc header in drivers/rtc
arm: at91: move reset controller header to arm/arm/mach-at91
arm: at91: move pit define to the driver
arm: at91: move at91_shdwc.h to arch/arm/mach-at91
arm: at91: move board header to arch/arm/mach-at91
arn: at91: move at91_tc.h to arch/arm/mach-at91
arm: at91 move at91_aic.h to arch/arm/mach-at91
arm: at91 move board.h to arch/arm/mach-at91
arm: at91: move platfarm_data to include/linux/platform_data/atmel.h
arm: at91: drop machine defconfig
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The debug-leds driver should not rely on hard coded macro for
the iomem size but use the resource size instead.
Signed-off-by: Benoit Cousson <b-cousson@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
arch/arm/mach-omap2/prcm.c and arch/arm/plat-omap/include/plat/prcm.h
are now completely unused and can be removed.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Tested-by: Vaibhav Hiremath <hvaibhav@ti.com>
Split omap2_set_globals_prcm() into PRM, CM, and PRCM_MPU variants, since
these are all separate IP blocks. This should make it easier to move the
PRM, CM, PRCM_MPU code into drivers/ in future patchsets.
At this point arch/arm/plat-omap/include/plat/prcm.h is empty; a
subsequent patch will remove it, and remove the #include from all the
files that #include it.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Tested-by: Vaibhav Hiremath <hvaibhav@ti.com>
Now that all users of mach-omap2/omap2_cm_wait_idlest() have been removed,
delete the function and its supporting macros and prototypes.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Tested-by: Vaibhav Hiremath <hvaibhav@ti.com>
Get rid of the mach-omap2/common.c globals by moving the global
initialization for IP block addresses that must occur early into
mach-omap2/io.c. In the process, remove the *_map_common_io*() and
SoC-specific *set_globals* functions.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Tested-by: Vaibhav Hiremath <hvaibhav@ti.com>
omap_prcm_get_reset_sources() is now unused; so, remove it.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Tested-by: Vaibhav Hiremath <hvaibhav@ti.com>
The only thing omap_init_consistent_dma_size() does is increase the
consistent DMA size if CONFIG_FB_OMAP_CONSISTENT_DMA_SIZE is defined.
Increasing the consistent DMA size should no longer be needed with CMA
in place.
This patch removes omap_init_consistent_dma_size() and also
arch/arm/mach-omap2/io.c:omap_common_init_early() which becomes an empty
function.
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
[tony@atomide.com: updated for moved dma.h]
Signed-off-by: Tony Lindgren <tony@atomide.com>
struct uart_omap_port and struct uart_omap_dma, and associated
definitions are private to the driver, so there's no point them sitting
in an include file under arch/arm. Move them into the driver itself.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Now mach/hardware.h is empty for omap2+ and can be
removed except for plat-omap/dmtimer.c for omap1.
Also the include of mach/irqs.h can now be removed
for shared plat-omap/i2c.c as it's no longer needed.
Signed-off-by: Tony Lindgren <tony@atomide.com>
In order to add device-tree support to the timer driver the following changes
were made ...
1. Allocate system timers (used for clock-events and clock-source) based upon
timer properties rather than using an hard-coded timer instance ID. To allow
this a new helper function called omap_dmtimer_find_by_property() has been
added for finding a timer with the particular properties in the device-tree
blob. Please note that this is an internal helper function for system timers
only to find a timer in the device-tree blob. This cannot be used by device
drivers, another API has been added for that (see below). Timers that are
allocated for system timers are dynamically disabled at boot time by adding
a status property with the value "disabled" to the timer's device-tree node.
Please note that when allocating system timers we now pass a timer ID and
timer property. The timer ID is only be used for allocating a timer when
booting without device-tree. Once device-tree migration is complete, all
the timer ID references will be removed.
2. System timer resources (memory and interrupts) are directly obtained from
the device-tree timer node when booting with device-tree, so that system
timers are no longer reliant upon the OMAP HWMOD framework to provide these
resources.
3. If DT blob is present, then let device-tree create the timer devices
dynamically.
4. When device-tree is present the "id" field in the platform_device structure
(pdev->id) is initialised to -1 and hence cannot be used to identify a timer
instance. Due to this the following changes were made ...
a). The API omap_dm_timer_request_specific() is not supported when using
device-tree, because it uses the device ID to request a specific timer.
This function will return an error if called when device-tree is present.
Users of this API should use omap_dm_timer_request_by_cap() instead.
b). When removing the DMTIMER driver, the timer "id" was used to identify the
timer instance. The remove function has been modified to use the device
name instead of the "id".
5. When device-tree is present the platform_data structure will be NULL and so
check for this.
6. The OMAP timer device tree binding has the following optional parameters ...
a). ti,timer-alwon --> Timer is in an always-on power domain
b). ti,timer-dsp --> Timer can generate an interrupt to the on-chip DSP
c). ti,timer-pwm --> Timer can generate a PWM output
d). ti,timer-secure --> Timer is reserved on a secure OMAP device
Search for the above parameters and set the appropriate timer attribute
flags.
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Currently OMAP timers can be requested by requesting any available or by a
numerical device ID. If a specific timer is required because it has a particular
capability, such as can interrupt the on-chip DSP in addition to the ARM CPU,
then the user needs to know the device ID of the timer with this feature.
Therefore, add a new API called omap_dm_timer_request_by_cap() that allows
drivers to request a timer by capability.
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Jon Hunter
Arnd Bergmann
Benoit Cousson
Tony Lindgren
Paul Walmsley
Tomi Valkeinen
Russell King