On the r7s72100 Genmai board the MTU2 driver currently triggers a common
clock framework WARN_ON(enable_count) when disabling the clock due to
the MTU2 driver after recent callback rework may call ->set_state_shutdown()
multiple times. A similar issue was spotted for the TMU driver and fixed in:
452b132 clocksource/drivers/sh_tmu: Fix traceback spotted in -next
On r7s72100 Genmai v4.3-rc7 built with shmobile_defconfig spits out the
following during boot:
sh_mtu2 fcff0000.timer: ch0: used for clock events
------------[ cut here ]------------
WARNING: CPU: 0 PID: 1 at drivers/clk/clk.c:675 clk_core_disable+0x2c/0x6c()
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.3.0-rc7 #1
Hardware name: Generic R7S72100 (Flattened Device Tree)
Backtrace:
[<c00133d4>] (dump_backtrace) from [<c0013570>] (show_stack+0x18/0x1c)
[<c0013558>] (show_stack) from [<c01c7aac>] (dump_stack+0x74/0x90)
[<c01c7a38>] (dump_stack) from [<c00272fc>] (warn_slowpath_common+0x88/0xb4)
[<c0027274>] (warn_slowpath_common) from [<c0027400>] (warn_slowpath_null+0x24/0x2c)
[<c00273dc>] (warn_slowpath_null) from [<c03a9320>] (clk_core_disable+0x2c/0x6c)
[<c03a92f4>] (clk_core_disable) from [<c03aa0a0>] (clk_disable+0x40/0x4c)
[<c03aa060>] (clk_disable) from [<c0395d2c>] (sh_mtu2_disable+0x24/0x50)
[<c0395d08>] (sh_mtu2_disable) from [<c0395d6c>] (sh_mtu2_clock_event_shutdown+0x14/0x1c)
[<c0395d58>] (sh_mtu2_clock_event_shutdown) from [<c007d7d0>] (clockevents_switch_state+0xc8/0x114)
[<c007d708>] (clockevents_switch_state) from [<c007d834>] (clockevents_shutdown+0x18/0x28)
[<c007d81c>] (clockevents_shutdown) from [<c007dd58>] (clockevents_exchange_device+0x70/0x78)
[<c007dce8>] (clockevents_exchange_device) from [<c007e578>] (tick_check_new_device+0x88/0xe0)
[<c007e4f0>] (tick_check_new_device) from [<c007daf0>] (clockevents_register_device+0xac/0x120)
[<c007da44>] (clockevents_register_device) from [<c0395be8>] (sh_mtu2_probe+0x230/0x350)
[<c03959b8>] (sh_mtu2_probe) from [<c028b6f0>] (platform_drv_probe+0x50/0x98)
Reported-by: Chris Brandt <chris.brandt@renesas.com>
Fixes: 19a9ffb ("clockevents/drivers/sh_mtu2: Migrate to new 'set-state' interface")
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
The global spinlock is used to protect the shared start/stop register.
Now that all MTU2 channels are handled by a single device instance, use
a per-device spinlock.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Tested-by: Wolfram Sang <wsa@sang-engineering.com>
The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message.
[dlezcano] : refreshed against latest modifications: kmalloc -> kzalloc
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Do not include the paragraph about writing to the Free Software
Foundation's mailing address from the sample GPL notice. The FSF has
changed addresses in the past, and may do so again. Linux already
includes a copy of the GPL.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Tested-by: Wolfram Sang <wsa@sang-engineering.com>
The sh_mtu2 driver gets the MTU2 functional clock using a connection ID
of "mtu2_fck". While all SH SoCs create clock lookup entries with a NULL
device ID and a "mtu2_fck" connection ID, the ARM SoCs use the device ID
only with a NULL connection ID. This works on legacy platforms but will
break on ARM with DT boot.
Fix the situation by using a connection ID of "fck" in the non-legacy
platform data case. Clock lookup entries will be renamed to use the
device ID as well as the connection ID as platforms get moved to new
platform data. The legacy code will eventually be dropped, leaving us
with device ID based clock lookup, compatible with DT boot.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Tested-by: Wolfram Sang <wsa@sang-engineering.com>
MTU2 hardware devices can support multiple channels, with global
registers and per-channel registers. The sh_mtu2 driver currently models
the hardware with one Linux device per channel. This model makes it
difficult to handle global registers in a clean way.
Add support for a new model that uses one Linux device per timer with
multiple channels per device. This requires changes to platform data,
add new channel configuration fields.
Support for the legacy model is kept and will be removed after all
platforms switch to the new model.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Tested-by: Wolfram Sang <wsa@sang-engineering.com>
The channel memory base is channel-specific, add it to the channel
structure in preparation for support of multiple channels per device.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Tested-by: Wolfram Sang <wsa@sang-engineering.com>
The driver claims it needs to register an interrupt handler too early
for request_irq(). This might have been true in the past, but the only
meaningful difference between request_irq() and setup_irq() today is an
additional kzalloc() call in request_irq(). As the driver calls
kmalloc() itself we know that the slab allocator is available, we can
thus switch to request_irq().
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Tested-by: Wolfram Sang <wsa@sang-engineering.com>
Kuninori Morimoto
Kees Cook
Magnus Damm
Viresh Kumar
Laurent Pinchart
Jingoo Han