Current OMAP code supports couple of clocksource options based
on compilation flag (CONFIG_OMAP_32K_TIMER). The 32KHz sync-timer
and a gptimer which can run on 32KHz or system clock (e.g 38.4 MHz).
So there can be 3 options -
1. 32KHz sync-timer
2. Sys_clock based (e.g 13/19.2/26/38.4 MHz) gptimer
3. 32KHz based gptimer.
The optional gptimer based clocksource was added so that it can
give the high precision than sync-timer, so expected usage was 2
and not 3.
Unfortunately option 2, clocksource doesn't meet the requirement of
free-running clock as per clocksource need. It stops in low power states
when sys_clock is cut. That makes gptimer based clocksource option
useless for OMAP2/3/4 devices with sys_clock as a clock input.
So, in order to use option 2, deeper idle state MUST be disabled.
Option 3 will still work but it is no better than 32K sync-timer
based clocksource.
We must support both sync timer and gptimer based clocksource as
some OMAP based derivative SoCs like AM33XX does not have the
sync timer.
Considering above, make sync-timer and gptimer clocksource runtime
selectable so that both OMAP and AMXXXX continue to use the same code.
And, in order to precisely configure/setup sched_clock for given
clocksource, decision has to be made early enough in boot sequence.
So, the solution is,
Use standard kernel parameter ("clocksource=") to override
default 32k_sync-timer, in addition to this, we also use hwmod database
lookup mechanism, through which at run-time we can identify availability
of 32k-sync timer on the device, else fall back to gptimer.
Also, moved low-level SoC specific init code to respective files,
(mach-omap1/timer32k.c and mach-omap2/timer.c)
Signed-off-by: Vaibhav Hiremath <hvaibhav@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Kevin Hilman <khilman@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Tarun Kanti DebBarma <tarun.kanti@ti.com>
Cc: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Depending on the bootloader, passing command-line arguments
with spaces may have issues. Some bootloaders doesn't seem
to pass along the quotes, passing only 'gp' part of the string,
which leads to wrong override configuration.
The only affected kernel parameter configuration for OMAP family
is "clocksource=", used to override kernel clocksource.
So this patch changes "gp timer" => "gp_timer", for clockevent,
clocksource and timer irq_handler.
Signed-off-by: Vaibhav Hiremath <hvaibhav@ti.com>
Acked-by: Kevin Hilman <khilman@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
We do not use iclk anywhere in the dmtimer driver and so removing it.
Hence removing the timer iclk entries from OMAP4 clkdev table as well.
Signed-off-by: Tarun Kanti DebBarma <tarun.kanti@ti.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
arch/arm/mach-omap2/timer.c pokes around inside the hwmod data
structures. Since the hwmod data structures are about to change, this
code will break. This patch modifies the timer code to use
recently-added hwmod functions instead.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Tony Lindgren <tony@atomide.com>
Add support for the new smp_twd runtime registration interface
to the OMAP4 platforms, and remove the old compile-time support.
Tested on Panda.
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Commit 2f0778af (ARM: 7205/2: sched_clock: allow sched_clock to be
selected at runtime) had a typo for the case when CONFIG_OMAP_32K_TIMER
is not set.
In dmtimer_read_sched_clock(), wrong argument was getting passed to
__omap_dm_timer_read_counter() function call; instead of "&clksrc",
we were passing "clksrc.io_base", which results into kernel crash.
To reproduce kernel crash, just disable the CONFIG_OMAP_32K_TIMER config
option (and DEBUG_LL) and build/boot the kernel.
This will use dmtimer as a kernel clocksource and lead to kernel
crash during boot -
[ 0.000000] OMAP clocksource: GPTIMER2 at 26000000 Hz
[ 0.000000] sched_clock: 32 bits at 26MHz, resolution 38ns, wraps every
165191ms
[ 0.000000] Unable to handle kernel paging request at virtual address
00030ef1
[ 0.000000] pgd = c0004000
[ 0.000000] [00030ef1] *pgd=00000000
[ 0.000000] Internal error: Oops: 5 [#1] SMP
[ 0.000000] Modules linked in:
[ 0.000000] CPU: 0 Not tainted (3.3.0-rc1-11574-g0c76665-dirty #3)
[ 0.000000] PC is at dmtimer_read_sched_clock+0x18/0x4c
[ 0.000000] LR is at update_sched_clock+0x10/0x84
[ 0.000000] pc : [<c00243b8>] lr : [<c0018684>] psr: 200001d3
[ 0.000000] sp : c0641f38 ip : c0641e18 fp : 0000000a
[ 0.000000] r10: 151c3303 r9 : 00000026 r8 : 76276259
[ 0.000000] r7 : 00028547 r6 : c065ac80 r5 : 431bde82 r4 : c0655968
[ 0.000000] r3 : 00030ef1 r2 : fb032000 r1 : 00000028 r0 : 00000001
Signed-off-by: Vaibhav Hiremath <hvaibhav@ti.com>
[tony@atomide.com: updated comments]
Signed-off-by: Tony Lindgren <tony@atomide.com>
sched_clock() is yet another blocker on the road to the single
image. This patch implements an idea by Russell King:
http://www.spinics.net/lists/linux-omap/msg49561.html
Instead of asking the platform to implement both sched_clock()
itself and the rollover callback, simply register a read()
function, and let the ARM code care about sched_clock() itself,
the conversion to ns and the rollover. sched_clock() uses
this read() function as an indirection to the platform code.
If the platform doesn't provide a read(), the code falls back
to the jiffy counter (just like the default sched_clock).
This allow some simplifications and possibly some footprint gain
when multiple platforms are compiled in. Among the drawbacks,
the removal of the *_fixed_sched_clock optimization which could
negatively impact some platforms (sa1100, tegra, versatile
and omap).
Tested on 11MPCore, OMAP4 and Tegra.
Cc: Imre Kaloz <kaloz@openwrt.org>
Cc: Eric Miao <eric.y.miao@gmail.com>
Cc: Colin Cross <ccross@android.com>
Cc: Erik Gilling <konkers@android.com>
Cc: Olof Johansson <olof@lixom.net>
Cc: Sascha Hauer <kernel@pengutronix.de>
Cc: Alessandro Rubini <rubini@unipv.it>
Cc: STEricsson <STEricsson_nomadik_linux@list.st.com>
Cc: Lennert Buytenhek <kernel@wantstofly.org>
Cc: Ben Dooks <ben-linux@fluff.org>
Tested-by: Jamie Iles <jamie@jamieiles.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Krzysztof Halasa <khc@pm.waw.pl>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
As suggested by Russell King - ARM Linux <linux@arm.linux.org.uk>,
there's no need to keep local prototypes in non-local headers.
Add mach-omap1/common.h and mach-omap2/common.h and move the
local prototypes there from plat/common.h and mach/omap4-common.h.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Remove the structure since a default one is now available.
Signed-off-by: Benoit Cousson <b-cousson@ti.com>
Cc: Kevin Hilman <khilman@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Clock is enabled only when timer is started and disabled when the the timer
is stopped. Therefore before accessing registers in functions clock is enabled
and then disabled back at the end of access. Context save is done dynamically
whenever the registers are modified. Context restore is called when context is
lost.
Signed-off-by: Tarun Kanti DebBarma <tarun.kanti@ti.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
[tony@atomide.com: updated to use revision instead of tidr]
Signed-off-by: Tony Lindgren <tony@atomide.com>
Pass the reserved flag in pdata and use it. We can
now make sys_timer_reserved static to mach-omap2/timer.c.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Register timer devices by going through hwmod database using
hwmod API. The driver probes each of the registered devices.
Functionality which are already performed by hwmod framework
are removed from timer code. New set of timers present on
OMAP4 are now supported.
Signed-off-by: Tarun Kanti DebBarma <tarun.kanti@ti.com>
Acked-by: Cousson, Benoit <b-cousson@ti.com>
[tony@atomide.com: folded in spinlock changes, left out is_omap2]
Signed-off-by: Tony Lindgren <tony@atomide.com>
Add routines to converts dmtimers to platform devices. The device data
is obtained from hwmod database of respective platform and is registered
to device model after successful binding to driver.
In addition, capability attribute of each of the timers is added in
hwmod database.
Signed-off-by: Tarun Kanti DebBarma <tarun.kanti@ti.com>
Signed-off-by: Thara Gopinath <thara@ti.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Cousson, Benoit <b-cousson@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
The registers are slightly different between v1 and v2 ip that
is available in omap4 and later for some timers.
Add support for v2 ip by mapping the interrupt related registers
separately and adding func_base for the functional registers.
Also disable dmtimer driver features on omap4 for now as
those need the hwmod conversion series to deal with enabling
the timers properly in omap_dm_timer_init.
Signed-off-by: Afzal Mohammed <afzal@ti.com>
Tested-by: Hemant Pedanekar <hemantp@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
If CONFIG_OMAP_32K_TIMER is not selected and dmtimer is used as clocksource, the
timer stops counting once overflow occurs as it was not set in autoreload mode.
This results into timekeeping failure: for example, 'sleep 1' at the shell after
the timer counter overflow would hang.
This patch sets up autoreload when starting the clocksource timer which fixes
the above issue.
Signed-off-by: Hemant Pedanekar <hemantp@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
We can keep everything sys_timer and gptimer.c related code in
timer.c as the code will be very minimal.
Later on we can also remove timer-mpu.c, as it can be called from
omap4_timer_init function.
This allows us to get rid of confusing existing files. We currently
have timer-gp.c, timer-mpu.c, and patches have been posted to add
dmtimer.c. There's no need to have these multiple files, we can
put everything into timer.c.
Signed-off-by: Tony Lindgren <tony@atomide.com>
2011-06-27 12:14:02 -07:00
Renamed from arch/arm/mach-omap2/timer-gp.c (Browse further)
