Commit Graph

8 Commits

Author SHA1 Message Date
Marek Szyprowski
ecb1f1f731 clk: samsung: Convert common drivers to the new clk_hw API
Clock providers should use the new struct clk_hw based API, so convert
Samsung clock providers and their helper functions to the new approach.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
2017-06-07 22:47:57 +02:00
Marek Szyprowski
7288de7451 clk: samsung: Add local variable to match its purpose
Add new variable to avoid using clk pointer for different purposes across
the exynos_register_cpu_clock() function. This will help in future rewrite
for the new clk_hw API.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
2017-06-07 22:47:56 +02:00
Bartlomiej Zolnierkiewicz
53f69967dc clk: samsung: cpu: prepare for adding Exynos5433 CPU clocks
Exynos5433 uses different register layout for CPU clock registers
than earlier SoCs so add new code for handling this layout.  Also
add new CLK_CPU_HAS_E5433_REGS_LAYOUT flag to request using it.

There should be no functional change resulting from this patch.

Cc: Kukjin Kim <kgene@kernel.org>
CC: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
2016-06-02 11:18:20 +02:00
Marek Szyprowski
6b4feaea25 clk: exynos: use irqsave version of spin_lock to avoid deadlock with irqs
It is allowed to enable/disable clocks from interrupts, so common Exynos
ARM clock management code for CPUfreq should use 'irqsave' version of
spin_lock calls to avoid potential deadlock caused by spin_lock recursion.
The same spin_lock is used by gate/mux clocks during enable/disable calls.

This deadlock, can be reproduced by enabling CPUfreq (ondemand or
userspace) and decoding video with s5p-mfc driver.

Relevant stack trace:
[ 5928.061534] BUG: spinlock recursion on CPU#0, bash/1252
[ 5928.061609]  lock: 0xee80454c, .magic: dead4ead, .owner: bash/1252, .owner_cpu: 0
[ 5928.068586] CPU: 0 PID: 1252 Comm: bash Tainted: G        W       4.4.0-rc4-00001-g447a7fd #678
[ 5928.077260] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
[ 5928.083359] [<c00153dc>] (unwind_backtrace) from [<c00121b4>] (show_stack+0x10/0x14)
[ 5928.091072] [<c00121b4>] (show_stack) from [<c0213e28>] (dump_stack+0x68/0xb8)
[ 5928.098275] [<c0213e28>] (dump_stack) from [<c005c1ec>] (do_raw_spin_lock+0x184/0x1ac)
[ 5928.106177] [<c005c1ec>] (do_raw_spin_lock) from [<c05cfa98>] (_raw_spin_lock_irqsave+0x20/0x28)
[ 5928.114943] [<c05cfa98>] (_raw_spin_lock_irqsave) from [<c0468698>] (clk_gate_endisable+0x24/0x98)
[ 5928.123882] [<c0468698>] (clk_gate_endisable) from [<c0464d40>] (clk_core_disable+0x60/0x84)
[ 5928.132299] [<c0464d40>] (clk_core_disable) from [<c0465e00>] (clk_disable+0x24/0x30)
[ 5928.140117] [<c0465e00>] (clk_disable) from [<c03f3b80>] (s5p_mfc_handle_frame+0x254/0x860)
[ 5928.148445] [<c03f3b80>] (s5p_mfc_handle_frame) from [<c03f4b34>] (s5p_mfc_irq+0x890/0xa24)
[ 5928.156778] [<c03f4b34>] (s5p_mfc_irq) from [<c00627bc>] (handle_irq_event_percpu+0x50/0x14c)
[ 5928.165283] [<c00627bc>] (handle_irq_event_percpu) from [<c00628f0>] (handle_irq_event+0x38/0x5c)
[ 5928.174143] [<c00628f0>] (handle_irq_event) from [<c0065864>] (handle_fasteoi_irq+0xdc/0x1a4)
[ 5928.182645] [<c0065864>] (handle_fasteoi_irq) from [<c0062090>] (generic_handle_irq+0x18/0x28)
[ 5928.191236] [<c0062090>] (generic_handle_irq) from [<c00621a4>] (__handle_domain_irq+0x6c/0xdc)
[ 5928.199917] [<c00621a4>] (__handle_domain_irq) from [<c0009470>] (gic_handle_irq+0x4c/0x98)
[ 5928.208249] [<c0009470>] (gic_handle_irq) from [<c0012c54>] (__irq_svc+0x54/0x90)
[ 5928.215709] Exception stack(0xeddb5cb8 to 0xeddb5d00)
[ 5928.220745] 5ca0:                                                       ee80454c faddfadc
[ 5928.228906] 5cc0: 00000000 01000001 ee831ce0 f8114200 ee807c00 01130520 00000403 eddb5d84
[ 5928.237063] 5ce0: ee807c48 2faf0800 ee807c0c eddb5d08 c046b618 c046b634 20000053 ffffffff
[ 5928.245225] [<c0012c54>] (__irq_svc) from [<c046b634>] (exynos_cpuclk_notifier_cb+0x170/0x270)
[ 5928.253823] [<c046b634>] (exynos_cpuclk_notifier_cb) from [<c003cb58>] (notifier_call_chain+0x44/0x84)
[ 5928.263106] [<c003cb58>] (notifier_call_chain) from [<c003ccd4>] (__srcu_notifier_call_chain+0x6c/0x9c)
[ 5928.272480] [<c003ccd4>] (__srcu_notifier_call_chain) from [<c003cd1c>] (srcu_notifier_call_chain+0x18/0x20)
[ 5928.282288] [<c003cd1c>] (srcu_notifier_call_chain) from [<c0464ed0>] (__clk_notify+0x6c/0x74)
[ 5928.290881] [<c0464ed0>] (__clk_notify) from [<c0465388>] (clk_propagate_rate_change+0xa0/0xac)
[ 5928.299561] [<c0465388>] (clk_propagate_rate_change) from [<c0465378>] (clk_propagate_rate_change+0x90/0xac)
[ 5928.309370] [<c0465378>] (clk_propagate_rate_change) from [<c04666fc>] (clk_core_set_rate_nolock+0x64/0xa8)
[ 5928.319091] [<c04666fc>] (clk_core_set_rate_nolock) from [<c0466760>] (clk_set_rate+0x20/0x30)
[ 5928.327686] [<c0466760>] (clk_set_rate) from [<c0428c70>] (set_target+0xe8/0x23c)
[ 5928.335152] [<c0428c70>] (set_target) from [<c04244d0>] (__cpufreq_driver_target+0x184/0x29c)
[ 5928.343655] [<c04244d0>] (__cpufreq_driver_target) from [<c0427128>] (cpufreq_set+0x44/0x64)
[ 5928.352074] [<c0427128>] (cpufreq_set) from [<c0423948>] (store_scaling_setspeed+0x5c/0x74)
[ 5928.360407] [<c0423948>] (store_scaling_setspeed) from [<c04238d0>] (store+0x7c/0x98)
[ 5928.368221] [<c04238d0>] (store) from [<c0132540>] (sysfs_kf_write+0x44/0x48)
[ 5928.375338] [<c0132540>] (sysfs_kf_write) from [<c0131b9c>] (kernfs_fop_write+0xb8/0x1bc)
[ 5928.383496] [<c0131b9c>] (kernfs_fop_write) from [<c00d71f8>] (__vfs_write+0x2c/0xd4)
[ 5928.391308] [<c00d71f8>] (__vfs_write) from [<c00d7de8>] (vfs_write+0xa0/0x144)
[ 5928.398598] [<c00d7de8>] (vfs_write) from [<c00d8048>] (SyS_write+0x44/0x84)
[ 5928.405631] [<c00d8048>] (SyS_write) from [<c000f540>] (ret_fast_syscall+0x0/0x3c)

CC: stable@vger.kernel.org  # v4.2+
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
2015-12-16 16:36:03 +01:00
Bartlomiej Zolnierkiewicz
9e294bf88a clk: samsung: fix cpu clock's flags checking
CLK_CPU_HAS_DIV1 and CLK_CPU_NEEDS_DEBUG_ALT_DIV masks were
incorrectly used as a bit numbers.  Fix it.

Tested on Exynos4210 based Origen board and on Exynos5250 based
Arndale board.

Cc: Tomasz Figa <tomasz.figa@gmail.com>
Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Thomas Abraham <thomas.ab@samsung.com>
Fixes: ddeac8d96 ("clk: samsung: add infrastructure to register cpu clocks")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Javier Martinez Canillas <javier@dowhile0.org>
Acked-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-09-22 09:53:51 -07:00
Stephen Boyd
0454159fa9 clk: samsung: Convert to clk_hw based provider APIs
We're removing struct clk from the clk provider API, so switch
this code to using the clk_hw based provider APIs.

Cc: Chanwoo Choi <cw00.choi@samsung.com>
Acked-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Cc: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-08-24 16:48:53 -07:00
Stephen Boyd
6f1ed07a14 clk: samsung: Properly include clk.h and clkdev.h
Clock provider drivers generally shouldn't include clk.h because
it's the consumer API. Only include clk.h in files that are
using it. The clkdev.h header isn't always used either, so remove
it and add in slab.h where files were relying on it to include
slab for them.

Cc: Chanwoo Choi <cw00.choi@samsung.com>
Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>
Cc: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-07-20 11:11:11 -07:00
Thomas Abraham
ddeac8d968 clk: samsung: add infrastructure to register cpu clocks
The CPU clock provider supplies the clock to the CPU clock domain. The
composition and organization of the CPU clock provider could vary among
Exynos SoCs. A CPU clock provider can be composed of clock mux, dividers
and gates. This patch defines a new clock type for CPU clock provider and
adds infrastructure to register the CPU clock providers for Samsung
platforms.

Changes by Bartlomiej:
- fixed issue with setting lower dividers before the parent clock speed
  was lowered (the issue resulted in lockup on Exynos4210 SoC based
  Origen board when "ondemand" cpufreq governor was stress tested)
- fixed missing spin_unlock on error in exynos_cpuclk_post_rate_change()
  problem by moving cfg_data search outside of the spin locked area
- removed leftover kfree() in exynos_register_cpu_clock() that could
  result in dereferencing the NULL pointer on error
- moved spin_lock earlier in exynos_cpuclk_pre_rate_change() to cover
  reading of E4210_SRC_CPU and E4210_DIV_CPU1 registers
- added missing "last chance" checks to wait_until_divider_stable() and
  wait_until_mux_stable() (needed in case that IRQ handling took long
  time to proceed and resulted in function printing incorrect error
  message about timeout)
- moved E4210_CPU_DIV[0,1]() macros just before their only users,
  this resulted in moving them from patch #2 to patch #3/6 ("clk:
  samsung: exynos4: add cpu clock configuration data and instantiate
  cpu clock")
- removed E5250_CPU_DIV[0,1](), E5420_EGL_DIV0() and E5420_KFC_DIV()
  macros for now
- added my Copyrights to drivers/clk/samsung/clk-cpu.c

Cc: Tomasz Figa <tomasz.figa@gmail.com>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Thomas Abraham <thomas.ab@samsung.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
2015-06-20 12:17:42 -07:00