Commit Graph

114 Commits

Author SHA1 Message Date
Markus Elfring
28fd7e9925 ARM: OMAP: Fix typos in two comment lines in _omap_dm_timer_request()
Adjust three words in this description.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2017-10-11 11:13:20 -07:00
Markus Elfring
16e7ea5380 ARM: OMAP: Improve a size determination in two functions
Replace the specification of data structures by pointer dereferences
as the parameter for the operator "sizeof" to make the corresponding size
determination a bit safer according to the Linux coding style convention.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2017-10-11 11:13:04 -07:00
Markus Elfring
d679950cb9 ARM: OMAP: Delete an error message for a failed memory allocation in two functions
Omit extra messages for a memory allocation failure in these functions.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2017-10-11 11:12:53 -07:00
Suman Anna
ea05d2eaf6 ARM: OMAP: dmtimer: check for fixed timers during config
The omap_dm_timer_set_source() function provides a means for client
users to configure the mux parent for a GPTimer's functional clock.
However, not all timers are configurable (Eg: Timer12 on DRA7 is fed
by an internal 32k oscillator clock, and does not have configurable
parent clocks). So, check for such cases and proceed with out throwing
an error.

Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2015-11-30 13:18:23 -08:00
Neil Armstrong
8c0cabd797 ARM: OMAP: add DT support for ti,dm816-timer
Adds ti,dm816-timer to the dmtimer OF match table.

Cc: Brian Hutchinson <b.hutchman@gmail.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2015-11-30 10:35:07 -08:00
Neil Armstrong
31a7448f4f ARM: OMAP: dmtimer: Add clock source from DT
Add a function which sets the timer source from the clocks
binding on dm_timer_prepare call.

In case the clocks property is not valid, it falls back to
the set_source() with 32_KHZ clock as default.

Suggested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2015-11-30 10:00:05 -08:00
Suman Anna
51b7e5728e ARM: OMAP: dmtimer: disable pm runtime on remove
Disable the pm_runtime of the device upon remove. This is
added to balance the pm_runtime_enable() invoked in the probe.

Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2015-03-17 10:44:58 -07:00
Suman Anna
a76fc9dda8 ARM: OMAP: dmtimer: check for pm_runtime_get_sync() failure
The current OMAP dmtimer probe does not check for the return
status of pm_runtime_get_sync() before initializing the timer
registers. Any timer with missing hwmod data would return a
failure here, and the access of registers without enabling the
clocks for the timer would trigger a l3_noc interrupt and a
kernel boot hang. Add proper checking so that the probe would
return a failure graciously without hanging the kernel boot.

Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2015-03-17 10:44:58 -07:00
Victor Kamensky
834cacfbef ARM: OMAP: dmtimer: raw read and write endian fix
All OMAP IP blocks expect LE data, but CPU may operate in BE mode.
Need to use endian neutral functions to read/write h/w registers.
I.e instead of __raw_read[lw] and __raw_write[lw] functions code
need to use read[lw]_relaxed and write[lw]_relaxed functions.
If the first simply reads/writes register, the second will byteswap
it if host operates in BE mode.

Changes are trivial sed like replacement of __raw_xxx functions
with xxx_relaxed variant.

Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org>
Signed-off-by: Taras Kondratiuk <taras.kondratiuk@linaro.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2014-05-08 07:09:54 -07:00
Linus Torvalds
38f56f33ca ARM: arm-soc device tree changes, part 2
These are mostly new device tree bindings for existing drivers, as well
 as changes to the device tree source files to add support for those
 devices, and a couple of new boards, most notably Samsung's Exynos5
 based Chromebook.
 
 The changes depend on earlier platform specific updates and touch
 the usual platforms: omap, exynos, tegra, mxs, mvebu and davinci.
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Merge tag 'dt-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC device tree updates (part 2) from Arnd Bergmann:
 "These are mostly new device tree bindings for existing drivers, as
  well as changes to the device tree source files to add support for
  those devices, and a couple of new boards, most notably Samsung's
  Exynos5 based Chromebook.

  The changes depend on earlier platform specific updates and touch the
  usual platforms: omap, exynos, tegra, mxs, mvebu and davinci."

* tag 'dt-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (169 commits)
  ARM: exynos: dts: cros5250: add EC device
  ARM: dts: Add sbs-battery for exynos5250-snow
  ARM: dts: Add i2c-arbitrator bus for exynos5250-snow
  ARM: dts: add mshc controller node for Exynos4x12 SoCs
  ARM: dts: Add chip-id controller node on Exynos4/5 SoC
  ARM: EXYNOS: Create virtual I/O mapping for Chip-ID controller using device tree
  ARM: davinci: da850-evm: add SPI flash support
  ARM: davinci: da850: override SPI DT node device name
  ARM: davinci: da850: add SPI1 DT node
  spi/davinci: add DT binding documentation
  spi/davinci: no wildcards in DT compatible property
  ARM: dts: mvebu: Convert mvebu device tree files to 64 bits
  ARM: dts: mvebu: introduce internal-regs node
  ARM: dts: mvebu: Convert all the mvebu files to use the range property
  ARM: dts: mvebu: move all peripherals inside soc
  ARM: dts: mvebu: fix cpus section indentation
  ARM: davinci: da850: add EHRPWM & ECAP DT node
  ARM/dts: OMAP3: fix pinctrl-single configuration
  ARM: dts: Add OMAP3430 SDP NOR flash memory binding
  ARM: dts: Add NOR flash bindings for OMAP2420 H4
  ...
2013-05-07 11:06:17 -07:00
Russell King
33b9f582c5 Merge branch 'cleanup' into for-linus
Conflicts:
	arch/arm/plat-omap/dmtimer.c
2013-05-02 21:31:29 +01:00
Russell King
c48cd65989 ARM: OMAP: use consistent error checking
Consistently check errors using the usual method used in the kernel
for much of its history.  For instance:

int gpmc_cs_set_timings(int cs, const struct gpmc_timings *t)
{
	int div;
	div = gpmc_calc_divider(t->sync_clk);
	if (div < 0)
		return div;
static int gpmc_set_async_mode(int cs, struct gpmc_timings *t)
{
...
	return gpmc_cs_set_timings(cs, t);

.....
	ret = gpmc_set_async_mode(gpmc_onenand_data->cs, &t);
	if (IS_ERR_VALUE(ret))
		return ret;

So, gpmc_cs_set_timings() thinks any negative return value is an error,
but where we check that in higher levels, only a limited range are
errors...

There is only _one_ use of IS_ERR_VALUE() in arch/arm which is really
appropriate, and that is in arch/arm/include/asm/syscall.h:

static inline long syscall_get_error(struct task_struct *task,
				     struct pt_regs *regs)
{
	unsigned long error = regs->ARM_r0;
	return IS_ERR_VALUE(error) ? error : 0;
}

because this function really does have to differentiate between error
return values and addresses which look like negative numbers (eg, from
mmap()).

So, here's a patch to remove them from OMAP, except for the above.

Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-05-02 19:54:22 +01:00
Jon Hunter
d1c6ccfe3d ARM: OMAP2+: Populate DMTIMER errata when using device-tree
Currently the DMTIMER errata flags are not being populated when using
device-tree. Add static platform data to populate errata flags when
using device-tree.

Please note that DMTIMER erratum i767 is applicable to OMAP3-5 devices
as well as AM335x devices.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Benoit Cousson <benoit.cousson@linaro.org>
2013-04-09 00:21:32 +02:00
Jon Hunter
002e1ec56d ARM: dts: OMAP2+: Update DMTIMER compatibility property
Update the DMTIMER compatibility property to reflect the register level
compatibilty between devices and update the various OMAP/AM timer
bindings with the appropriate compatibility string.

By doing this we can add platform specific data applicable to specific
timer versions to the driver. For example, errata flags can be populated
for the timer versions that are impacted.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Benoit Cousson <benoit.cousson@linaro.org>
2013-04-09 00:21:31 +02:00
Jon Hunter
8fc7fcb593 ARM: OMAP: Add function to request timer by node
Add a function so that OMAP dmtimers can be requested by device-tree
node. This allows for devices, such as the internal DSP, or drivers,
such as PWM, to reference a specific dmtimer node via the device-tree.

Given that there are several APIs available for requesting dmtimers
(by ID, by capability or by node) consolidate the code for all these
functions into a single helper function that can be used by these
request functions.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Benoit Cousson <benoit.cousson@linaro.org>
2013-04-09 00:21:31 +02:00
Jon Hunter
385c4c7b7c ARM: OMAP: Force dmtimer restore if context loss is not detectable
When booting with device-tree the function pointer for detecting context
loss is not populated. Ideally, the pm_runtime framework should be
enhanced to allow a means for reporting context/state loss and we could
avoid populating such function pointers altogether. In the interim until
a generic non-device specific solution is in place, force a restore of
the dmtimer when enabling the timer.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Benoit Cousson <benoit.cousson@linaro.org>
2013-04-09 00:21:30 +02:00
NeilBrown
9cc268d5bb ARM: OMAP: Simplify dmtimer context-loss handling
The context loss handling in dmtimer appears to assume that
omap_dm_timer_set_load_start() or omap_dm_timer_start() and
omap_dm_timer_stop() bracket all interactions.  Only the first two
restore the context and the last updates the context loss counter.
However omap_dm_timer_set_load() or omap_dm_timer_set_match() can
reasonably be called outside this bracketing, and the fact that they
call omap_dm_timer_enable() / omap_dm_timer_disable() suggest that
is expected.

So if, after a transition into and out of off-mode which would cause
the dm timer to loose all state, omap_dm_timer_set_match() is called
before omap_dm_timer_start(), the value read from OMAP_TIMER_CTRL_REG
will be 'wrong' and this wrong value will be stored context.tclr so
a subsequent omap_dm_timer_start() can fail (As the control register
is wrong).

Simplify this be doing the restore-from-context in
omap_dm_timer_enable() so that whenever the timer is enabled, the
context is correct. Also update the ctx_loss_count at the same time as
we notice it is wrong - these is no value in delaying this until the
omap_dm_timer_disable() as it cannot change while the timer is enabled.

Signed-off-by: NeilBrown <neilb@suse.de>
[jon-hunter@ti.com: minor update to subject and changed variable name]
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Benoit Cousson <benoit.cousson@linaro.org>
2013-04-09 00:21:29 +02:00
Russell King
86287958bd ARM: cleanup: clk_get() error handling
Use the correct IS_ERR() to determine if clk_get() returned an error.
Set timer->fclk to be an error value initially, and check everywhere
using IS_ERR().  This keeps the range of valid values for 'struct clk'
consistent.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-02-24 10:46:59 +00:00
Thierry Reding
5857bd98db ARM: Convert to devm_ioremap_resource()
Convert all uses of devm_request_and_ioremap() to the newly introduced
devm_ioremap_resource() which provides more consistent error handling.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-25 12:21:45 -08:00
Greg Kroah-Hartman
351a102dbf ARM: drivers: remove __dev* attributes.
CONFIG_HOTPLUG is going away as an option.  As a result, the __dev*
markings need to be removed.

This change removes the use of __devinit, __devexit_p, __devinitdata,
and __devexit from these drivers.

Based on patches originally written by Bill Pemberton, but redone by me
in order to handle some of the coding style issues better, by hand.

Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-03 15:57:04 -08:00
Srinivas Kandagatla
e4e9f7ea2e ARM/omap: use module_platform_driver macro
This patch removes some code duplication by using
module_platform_driver.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@st.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-12-17 10:50:41 -08:00
Jon Hunter
40fc3bb56e ARM: OMAP: Add platform data header for DMTIMERs
Move definition of dmtimer platform data structure in to its own header
under <linux/platform_data>.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
2012-11-16 10:35:08 -06:00
Jon Hunter
b0cadb3c86 ARM: OMAP: Define omap_dm_timer_prepare function as static
The omap_dm_timer_prepare function is a local function only used in the
dmtimer.c file. Therefore, make this a static function and remove its
declaration from the dmtimer.h file.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
2012-11-16 10:35:06 -06:00
Jon Hunter
ae6672cb47 ARM: OMAP: Clean-up dmtimer reset code
Only OMAP1 devices use the omap_dm_timer_reset() and so require the
omap_dm_timer_wait_for_reset() and __omap_dm_timer_reset() functions.
Therefore combine these into a single function called omap_dm_timer_reset()
and simplify the code.

The omap_dm_timer_reset() function is now the only place that is using the
omap_dm_timer structure member "sys_stat". Therefore, remove this member and
just use the register offset definition to simplify and clean-up the code. The
TISTAT register is only present on revision 1 timers and so check for this in
the omap_dm_timer_reset() function.

Please note that for OMAP1 devices, the TIOCP_CFG register does not have the
clock-activity field and so when we reset the timer for an OMAP1 device we
only need to configure the idle-mode field in the TIOCP_CFG register.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
2012-11-16 10:35:05 -06:00
Jon Hunter
b153883219 ARM: OMAP: Remove __omap_dm_timer_set_source function
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>
2012-11-12 16:23:57 -06:00
Jon Hunter
d7aba5540d ARM: OMAP: Remove unnecessary call to clk_get()
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>
2012-11-12 16:23:56 -06:00
Jon Hunter
4249d96ca3 ARM: OMAP: Add dmtimer interrupt disable function
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>
2012-11-12 16:23:55 -06:00
Jon Hunter
991ad16a92 ARM: OMAP: Fix spurious interrupts when using timer match feature
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>
2012-11-12 16:23:55 -06:00
Jon Hunter
1eaff71017 ARM: OMAP: Don't restore DMTIMER interrupt status register
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>
2012-11-12 16:23:54 -06:00
Jon Hunter
d3004bb43d ARM: OMAP: Don't restore of DMTIMER TISTAT register
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>
2012-11-12 16:23:53 -06:00
Jon Hunter
ffc957bd83 ARM: OMAP: Fix dmtimer reset for timer1
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>
2012-11-12 16:23:52 -06:00
Jon Hunter
7b44cf2c15 ARM: OMAP: Fix timer posted mode support
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>
2012-11-12 16:23:50 -06:00
Jon Hunter
bfd6d02112 ARM: OMAP3+: Implement timer workaround for errata i103 and i767
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>
2012-11-12 16:23:49 -06:00
Tony Lindgren
f56f52e02a Merge branch 'omap-for-v3.8/cleanup-headers-prepare-multiplatform-v3' into omap-for-v3.8/dt
Conflicts:
	arch/arm/plat-omap/dmtimer.c

Resolved as suggested by Jon Hunter.
2012-11-09 14:54:17 -08:00
Tony Lindgren
7136f8d88c ARM: OMAP: Remove unnecessary mach and plat includes
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>
2012-11-02 12:00:36 -07:00
Jon Hunter
9725f4451a ARM: OMAP: Add DT support for timer driver
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>
2012-11-02 13:16:30 -05:00
Jon Hunter
373fe0bdf9 ARM: OMAP: Add function to request a timer by capability
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>
2012-11-02 13:16:29 -05:00
Tony Lindgren
6e740f9a85 ARM: OMAP: Move omap-pm-noop.c local to mach-omap2
This code should be private to mach-omap2.

The only use for it in for omap1 has been in dmtimer.c
to check for context loss. However, omap1 does not
lose context during idle, so the code is not needed.
Further, omap1 timer has OMAP_TIMER_ALWON set, so omap1
was not hitting omap_pm_get_dev_context_loss_count()
test.

Cc: Jon Hunter <jon-hunter@ti.com>
Cc: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-10-31 15:37:13 -07:00
Tony Lindgren
1d5aef4950 ARM: OMAP: Make plat/omap-pm.h local to mach-omap2
We must move this for ARM common zImage support.

Note that neither drivers/media/rc/ir-rx51.c or
drivers/media/platform/omap3isp/ispvideo.c need
to include omap-pm.h, so this patch removes the
include for those files.

Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: Timo Kokkonen <timo.t.kokkonen@iki.fi>
Cc: linux-media@vger.kernel.org
Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-10-18 16:22:08 -07:00
Timo Kokkonen
c5491d1ae1 ARM: OMAP: dmtimers: Fix locking issue in omap_dm_timer_request*()
Calling omap_dm_timer_prepare while the spinlock is held is not
allowed as sleeping functions are called later on during the
preparation (namely within clk_get()).

dm_timer_lock is only required for protecting the
omap_timer_list. After the timer is marked as reserved, the lock is no
longer needed and should be freed.

Signed-off-by: Timo Kokkonen <timo.t.kokkonen@iki.fi>
Cc: Tarun Kanti DebBarma <tarun.kanti@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-08-13 06:23:16 -07:00
Jon Hunter
54f32a35f4 ARM: OMAP2+: Fix dmtimer set source clock failure
Calling the dmtimer function omap_dm_timer_set_source() fails if following a
call to pm_runtime_put() to disable the timer. For example the following
sequence would fail to set the parent clock ...

	omap_dm_timer_stop(gptimer);
	omap_dm_timer_set_source(gptimer, OMAP_TIMER_SRC_32_KHZ);

The following error message would be seen ...

omap_dm_timer_set_source: failed to set timer_32k_ck as parent

The problem is that, by design, pm_runtime_put() simply decrements the usage
count and returns before the timer has actually been disabled. Therefore,
setting the parent clock failed because the timer was still active when the
trying to set the parent clock. Setting a parent clock will fail if the clock
you are setting the parent of has a non-zero usage count. To ensure that this
does not fail use pm_runtime_put_sync() when disabling the timer.

Note that this will not be seen on OMAP1 devices, because these devices do
not use the clock framework for dmtimers.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Acked-by: Kevin Hilman <khilman@ti.com>
Cc: stable@vger.kernel.org
Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-08-07 23:45:54 -07:00
Tarun Kanti DebBarma
74dd9ec627 ARM: OMAP: dmtimer: use devm_ API and do some cleanup in probe()
Replace the regular kzalloc and ioremap with the devm_ equivalent
to simplify error handling. We don't need kree() any more in
omap_dm_timer_remove().

Also added *dev* pointer to reference pdev->dev which makes the
usage shorter in code.

Cc: Cousson, Benoit <b-cousson@ti.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@ti.com>
Cc: Rajendra Nayak <rnayak@ti.com>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Tarun Kanti DebBarma <tarun.kanti@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-07-05 02:15:55 -07:00
Jon Hunter
c59b537d87 ARM: OMAP2+: Simplify dmtimer clock aliases
The OMAP dmtimer driver allows you to dynamically configure the functional
clock that drives the timer logic. The dmtimer driver uses the device name and
a "con-id" string to search for the appropriate functional clock.

Currently, we define a clock alias for each functional clock source each timer
supports. Some functional clock sources are common to all of the timers on a
device and so for these clock sources we can use a single alias with a unique
con-id string.

The possible functional clock sources for an OMAP device are a 32kHz clock,
a system (MHz range) clock and (for OMAP2 only) an external clock. By defining
a unique con-id name for each of these (timer_32k_ck, timer_sys_ck and
timer_ext_ck) we can eliminate a lot of the clock aliases for timers. This
reduces code, speeds-up searches and clock initialisation time.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Acked-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-06-14 02:39:47 -07:00
Jon Hunter
2b2d352300 ARM: OMAP2+: Move dmtimer clock set function to dmtimer driver
OMAP1 uses an architecture specific function for setting the dmtimer clock
source, where as the OMAP2+ devices use the clock framework. Eventually OMAP1
device should also use the clock framework and hence we should not any
architecture specific functions.

For now move the OMAP2+ function for configuring the clock source into the
dmtimer driver. Therefore, we do no longer need to specify an architecture
specific function for setting the clock source for OMAP2+ devices. This will
simplify device tree migration of the dmtimers for OMAP2+ devices.

From now on, only OMAP1 devices should specify an architecture specific
function for setting the clock source via the platform data set_dmtimer_src()
function pointer.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-06-14 02:39:47 -07:00
Jon Hunter
bca4580845 ARM: OMAP1: Fix dmtimer support
OMAP1 dmtimer support is currently broken. When a dmtimer is requested by the
omap_dm_timer_request() function fails to allocate a dmtimer because the call
to clk_get() inside omap_dm_timer_prepare fails. The clk_get() fails simply
because the clock data for the OMAP1 dmtimers is not present.

Ideally this should be fixed by moving OMAP1 dmtimers to use the clock
framework. For now simply fix this by using the "TIMER_NEEDS_RESET" flag to
identify an OMAP1 device and avoid calling clk_get(). Although this is not
the ideal fix and should be corrected, this flag has already been use for the
same purpose in omap_dm_timer_stop().

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-06-14 02:39:47 -07:00
Jon Hunter
6615975bc5 ARM: OMAP: Add flag to indicate if a timer needs a manual reset
For OMAP1 devices, it is necessary to perform a manual reset of the timer.
Currently, this is indicating by setting the "needs_manual_reset" variable in
the platform data. Instead of using an extra variable to indicate this add a new
timer capabilities flag to indicate this and remove the "needs_manual_reset"
member from the platform data.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-06-14 02:39:47 -07:00
Jon Hunter
0b30ec1cb7 ARM: OMAP: Remove timer function pointer for context loss counter
For OMAP2+ devices, a function pointer that returns the number of times a timer
power domain has lost context is passed to the dmtimer driver. This function
pointer is only populated for OMAP2+ devices and it is pointing to a platform
function. Given that this is a platform function, we can simplify the code by
removing the function pointer and referencing the function directly. We can use
the OMAP_TIMER_ALWON flag to determine if we need to call this function for
OMAP1 and OMAP2+ devices.

The benefit of this change is the we can remove the function pointer from the
platform data and simplifies the dmtimer migration to device-tree.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-06-14 02:39:47 -07:00
Jon Hunter
1c2d076b58 ARM: OMAP: Remove loses_context variable from timer platform data
The platform data variable loses_context is used to determine if the timer may
lose its logic state during power transitions and so needs to be restored. This
information is also provided in the HWMOD device attributes for OMAP2+ devices
via the OMAP_TIMER_ALWON flag. When this flag is set the timer will not lose
context. So use the HWMOD device attributes to determine this.

For OMAP1 devices, loses_context is never set and so set the OMAP_TIMER_ALWON
flag for OMAP1 timers to ensure that code is equivalent.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-06-14 02:39:47 -07:00
Jon Hunter
d1c1691be5 ARM: OMAP: Add DMTIMER capability variable to represent timer features
Although the OMAP timers share a common hardware design, there are some
differences between the timer instances in a given device. For example, a timer
maybe in a power domain that can be powered-of, so can lose its logic state and
need restoring where as another may be in power domain that is always be on.
Another example, is a timer may support different clock sources to drive the
timer. This information is passed to the dmtimer via the following platform data
structure.

struct dmtimer_platform_data {
	int (*set_timer_src)(struct platform_device *pdev, int source);
	int timer_ip_version;
	u32 needs_manual_reset:1;
	bool loses_context;
	int (*get_context_loss_count)(struct device *dev);
};

The above structure uses multiple variables to represent the timer features.
HWMOD also stores the timer capabilities using a bit-mask that represents the
features supported. By using the same format for representing the timer
features in the platform data as used by HWMOD, we can ...

1. Use the flags defined in the plat/dmtimer.h to represent the features
   supported.
2. For devices using HWMOD, we can retrieve the features supported from HWMOD.
3. Eventually, simplify the platform data structure to be ...

struct dmtimer_platform_data {
	int (*set_timer_src)(struct platform_device *pdev, int source);
	u32 timer_capability;
}

Another benefit from doing this, is that it will simplify the migration of the
dmtimer driver to device-tree. For example, in the current OMAP2+ timer code the
"loses_context" variable is configured at runtime by calling an architecture
specific function. For device tree this creates a problem, because we would need
to call the architecture specific function from within the dmtimer driver.
However, such attributes do not need to be queried at runtime and we can look up
the attributes via HWMOD or device-tree.

This changes a new "capability" variable to the platform data and timer
structure so we can start removing and simplifying the platform data structure.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-06-14 02:39:07 -07:00
Jon Hunter
b7b4ff764f ARM: OMAP2+: Add dmtimer platform function to reserve systimers
During early boot, one or two dmtimers are reserved by the kernel as system
timers (for clocksource and clockevents). These timers are marked as reserved
and the dmtimer driver is notified which timers have been reserved via the
platform data information.

For OMAP2+ devices the timers reserved may vary depending on device and compile
flags. Therefore, it is not easy to assume which timers we be reserved for the
system timers. In order to migrate the dmtimer driver to support device-tree we
need a way to pass the timers reserved for system timers to the dmtimer driver.
Using the platform data structure will not work in the same way as it is
currently used because the platform data structure will be stored statically in
the dmtimer itself and the platform data will be selected via the device-tree
match device function (of_match_device).

There are a couple ways to workaround this. One option is to store the system
timers reserved for the kernel in the device-tree and query them on boot.
The downside of this approach is that it adds some delay to parse the DT blob
to search for the system timers. Secondly, for OMAP3 devices we have a
dependency on compile time flags and the device-tree would not be aware of that
kernel compile flags and so we would need to address that.

The second option is to add a function to the dmtimer code to reserved the
system timers during boot and so the dmtimer knows exactly which timers are
being used for system timers. This also allows us to remove the "reserved"
member from the timer platform data. This seemed like the simpler approach and
so was implemented here.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-06-14 02:39:06 -07:00