This patch implements DFLL suspend and resume operation.
During system suspend entry, CPU clock will switch CPU to safe
clock source of PLLP and disables DFLL clock output.
DFLL driver suspend confirms DFLL disable state and errors out on
being active.
DFLL is re-initialized during the DFLL driver resume as it goes
through complete reset during suspend entry.
Acked-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 655 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070034.575739538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
updates this time around. It's the usual pile of new drivers for new
hardware out there and the normal small fixes and updates, but then we
have some core framework changes too.
In the core framework, we introduce support for a clk_get_optional() API
to get clks that may not always be populated and a way to devm manage clkdev
lookups registered by provider drivers. We also do some refactoring to simplify
the interface between clkdev and the common clk framework so we can reuse the DT
parsing and clk_get() path in provider drivers in the future. This work will
continue in the next few cycles while we convert how providers specify clk
parents.
On the driver side, the biggest part of the dirstat is the Amlogic clk driver
that got support for the G12A SoC. It dominates with almost half the overall
diff, while the second largest part of the diff is in the i.MX clk driver
that gained support for imx8mm SoCs. After that, we have the Actions Semiconductor
and Qualcomm drivers rounding out the big part of the dirstat because they both
got new hardware support for SoCs. The rest is just various updates and non-critical
fixes for existing drivers.
Core:
- Convert a few clk bindings to JSON schema format
- Add a {devm_}clk_get_optional() API
- Add devm_clk_hw_register_clkdev() API to manage clkdev lookups
- Start rewriting clk parent registration and supporting device links
by moving around code that supports clk_get() and DT parsing of the
'clocks' property
New Drivers:
- Add Qualcomm MSM8998 RPM managed clks
- IPA clk support on Qualcomm RPMh clk controllers
- Actions Semi S500 SoC clk support
- Support for fixed rate clks populated from an MMIO register
- Add RPC (QSPI/HyperFLASH) clocks on Renesas R-Car V3H
- Add TMU (timer) clocks on Renesas RZ/G2E
- Add Amlogic G12A Always-On Clock Controller
- Add 32k clock generation for Amlogic AXG
- Add support for the Mali GPU clocks on Amlogic Meson8
- Add Amlogic G12A EE clock controller driver
- Add missing CANFD clocks on Renesas RZ/G2M and RZ/G2E
- Add i.MX8MM SoC clk driver support
Removed Drivers:
- Remove clps711x driver as the board support is gone
Updates:
- 3rd ECO fix for Mediatek MT2712 SoCs
- Updates for Qualcomm MSM8998 GCC clks
- Random static analysis fixes for clk drivers
- Support for sleeping gpios in the clk-gpio type
- Minor fixes for STM32MP1 clk driver (parents, critical flag, etc.)
- Split LCDC into two clks on the Marvell MMP2 SoC
- Various DT of_node refcount fixes
- Get rid of CLK_IS_BASIC from TI code (yay!)
- TI Autoidle clk support
- Fix Amlogic Meson8 APB clock ID name
- Claim input clocks through DT for Amlogic AXG and GXBB
- Correct the DU (display unit) parent clock on Renesas RZ/G2E
- Exynos5433 IMEM CMU crypto clk support (SlimSS)
- Fix for the PLL-MIPI on the Allwinner A23
- Fix Rockchip rk3328 PLL rate calculation
- Add SET_RATE_PARENT flag on display clk of Rockhip rk3066
- i.MX SCU clk driver clk_set_parent() and cpufreq support
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Merge tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux
Pull clk subsystem updates from Stephen Boyd:
"We have a fairly balanced mix of clk driver updates and clk framework
updates this time around. It's the usual pile of new drivers for new
hardware out there and the normal small fixes and updates, but then we
have some core framework changes too.
In the core framework, we introduce support for a clk_get_optional()
API to get clks that may not always be populated and a way to devm
manage clkdev lookups registered by provider drivers. We also do some
refactoring to simplify the interface between clkdev and the common
clk framework so we can reuse the DT parsing and clk_get() path in
provider drivers in the future. This work will continue in the next
few cycles while we convert how providers specify clk parents.
On the driver side, the biggest part of the dirstat is the Amlogic clk
driver that got support for the G12A SoC. It dominates with almost
half the overall diff, while the second largest part of the diff is in
the i.MX clk driver that gained support for imx8mm SoCs. After that,
we have the Actions Semiconductor and Qualcomm drivers rounding out
the big part of the dirstat because they both got new hardware support
for SoCs. The rest is just various updates and non-critical fixes for
existing drivers.
Core:
- Convert a few clk bindings to JSON schema format
- Add a {devm_}clk_get_optional() API
- Add devm_clk_hw_register_clkdev() API to manage clkdev lookups
- Start rewriting clk parent registration and supporting device links
by moving around code that supports clk_get() and DT parsing of the
'clocks' property
New Drivers:
- Add Qualcomm MSM8998 RPM managed clks
- IPA clk support on Qualcomm RPMh clk controllers
- Actions Semi S500 SoC clk support
- Support for fixed rate clks populated from an MMIO register
- Add RPC (QSPI/HyperFLASH) clocks on Renesas R-Car V3H
- Add TMU (timer) clocks on Renesas RZ/G2E
- Add Amlogic G12A Always-On Clock Controller
- Add 32k clock generation for Amlogic AXG
- Add support for the Mali GPU clocks on Amlogic Meson8
- Add Amlogic G12A EE clock controller driver
- Add missing CANFD clocks on Renesas RZ/G2M and RZ/G2E
- Add i.MX8MM SoC clk driver support
Removed Drivers:
- Remove clps711x driver as the board support is gone
Updates:
- 3rd ECO fix for Mediatek MT2712 SoCs
- Updates for Qualcomm MSM8998 GCC clks
- Random static analysis fixes for clk drivers
- Support for sleeping gpios in the clk-gpio type
- Minor fixes for STM32MP1 clk driver (parents, critical flag, etc.)
- Split LCDC into two clks on the Marvell MMP2 SoC
- Various DT of_node refcount fixes
- Get rid of CLK_IS_BASIC from TI code (yay!)
- TI Autoidle clk support
- Fix Amlogic Meson8 APB clock ID name
- Claim input clocks through DT for Amlogic AXG and GXBB
- Correct the DU (display unit) parent clock on Renesas RZ/G2E
- Exynos5433 IMEM CMU crypto clk support (SlimSS)
- Fix for the PLL-MIPI on the Allwinner A23
- Fix Rockchip rk3328 PLL rate calculation
- Add SET_RATE_PARENT flag on display clk of Rockhip rk3066
- i.MX SCU clk driver clk_set_parent() and cpufreq support"
* tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (150 commits)
dt-bindings: clock: imx8mq: Fix numbering overlaps and gaps
clk: ti: clkctrl: Fix clkdm_name regression for TI_CLK_CLKCTRL_COMPAT
clk: fixup default index for of_clk_get_by_name()
clk: Move of_clk_*() APIs into clk.c from clkdev.c
clk: Inform the core about consumer devices
clk: Introduce of_clk_get_hw_from_clkspec()
clk: core: clarify the check for runtime PM
clk: Combine __clk_get() and __clk_create_clk()
clk: imx8mq: add GPIO clocks to clock tree
clk: mediatek: correct cpu clock name for MT8173 SoC
clk: imx: Refactor entire sccg pll clk
clk: imx: scu: add cpu frequency scaling support
clk: mediatek: Mark bus and DRAM related clocks as critical
clk: mediatek: Add flags to mtk_gate
clk: mediatek: Add MUX_FLAGS macro
clk: qcom: gcc-sdm845: Define parent of PCIe PIPE clocks
clk: ingenic: Remove set but not used variable 'enable'
clk: at91: programmable: remove unneeded register read
clk: mediatek: using CLK_MUX_ROUND_CLOSEST for the clock of dpi1_sel
clk: mediatek: add MUX_GATE_FLAGS_2
...
Use DEFINE_DEBUGFS_ATTRIBUTE rather than DEFINE_SIMPLE_ATTRIBUTE
for debugfs files.
Semantic patch information:
Rationale: DEFINE_SIMPLE_ATTRIBUTE + debugfs_create_file()
imposes some significant overhead as compared to
DEFINE_DEBUGFS_ATTRIBUTE + debugfs_create_file_unsafe().
Generated by: scripts/coccinelle/api/debugfs/debugfs_simple_attr.cocci
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
When generating the OPP table, the voltages are round down with the
alignment from the regulator. The alignment should be applied for
voltages look up as well.
Based on the work of Penny Chiu <pchiu@nvidia.com>.
Signed-off-by: Joseph Lo <josephl@nvidia.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
The DFLL hardware supports two modes (I2C and PWM) for voltage control
when requesting a frequency. In this patch, we introduce PWM mode support.
To support that, we re-organize the LUT for unifying the table for both
cases of I2C and PWM mode. And generate that based on regulator info.
For the PWM-based regulator, we get this info from DT. And do the same as
the case of I2C LUT, which can help to map the PMIC voltage ID and voltages
that the regulator supported.
The other parts are the support code for initializing the DFLL hardware
to support PWM mode. Also, the register debugfs file is slightly
reworked to only show the i2c registers when I2C mode is in use.
Based on the work of Peter De Schrijver <pdeschrijver@nvidia.com>.
Signed-off-by: Joseph Lo <josephl@nvidia.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Use macro to simplify the code.
Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Actually report the error code from devm_regulator_get() which may as
well just be a probe deferral.
Signed-off-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Reviewed-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.
The return value of these functions were never checked in the end
anyway, so it is obvious this does not change any functionality :)
Cc: Peter De Schrijver <pdeschrijver@nvidia.com>
Cc: Prashant Gaikwad <pgaikwad@nvidia.com>
Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Both tegra124-dfll and clk-dfll are using platform_set_drvdata
to set drvdata of the exact same pdev while they use different
pointers for the drvdata. Once the drvdata has been overwritten
by tegra124-dfll, clk-dfll will never get its td pointer as it
expects.
Since tegra124-dfll merely needs its soc pointer in its remove
function, this patch fixes the bug by removing the overwriting
in the tegra124-dfll file and letting the tegra_dfll_unregister
return an soc pointer for it.
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Acked-By: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
This patch updates dev_pm_opp_find_freq_*() routines to get a reference
to the OPPs returned by them.
Also updates the users of dev_pm_opp_find_freq_*() routines to call
dev_pm_opp_put() after they are done using the OPPs.
As it is guaranteed the that OPPs wouldn't get freed while being used,
the RCU read side locking present with the users isn't required anymore.
Drop it as well.
This patch also updates all users of devfreq_recommended_opp() which was
returning an OPP received from the OPP core.
Note that some of the OPP core routines have gained
rcu_read_{lock|unlock}() calls, as those still use RCU specific APIs
within them.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com> [Devfreq]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Instead of copying parts of the CVB table into a separate structure,
keep track of the selected CVB table and directly reference data from
it.
Signed-off-by: Thierry Reding <treding@nvidia.com>
This flag is a no-op now. Remove usage of the flag.
Acked-by: Rhyland Klein <rklein@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
This contains a patch that allows the DFLL to use clock rates higher
than 2^31-1 Hz by using the ->determine_rate() operation instead of the
->round_rate() operation. Other than that there's a couple of cleanups
in preparation for Tegra210 support.
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Merge tag 'tegra-for-4.4-clk' of git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux into clk-next
clk: tegra: Changes for v4.4-rc1
This contains a patch that allows the DFLL to use clock rates higher
than 2^31-1 Hz by using the ->determine_rate() operation instead of the
->round_rate() operation. Other than that there's a couple of cleanups
in preparation for Tegra210 support.
The monitor code is used with DEBUG_FS only, so move it into the
corresponding #ifdef block to avoid potential compiler warnings.
Signed-off-by: Thierry Reding <treding@nvidia.com>
The OPP list needs to be protected against concurrent accesses. Using
simple RCU read locks does the trick and gets rid of the following
lockdep warning:
===============================
[ INFO: suspicious RCU usage. ]
4.2.0-next-20150908 #1 Not tainted
-------------------------------
drivers/base/power/opp.c:460 Missing rcu_read_lock() or dev_opp_list_lock protection!
other info that might help us debug this:
rcu_scheduler_active = 1, debug_locks = 0
4 locks held by kworker/u8:0/6:
#0: ("%s""deferwq"){++++.+}, at: [<c0040d8c>] process_one_work+0x118/0x4bc
#1: (deferred_probe_work){+.+.+.}, at: [<c0040d8c>] process_one_work+0x118/0x4bc
#2: (&dev->mutex){......}, at: [<c03b8194>] __device_attach+0x20/0x118
#3: (prepare_lock){+.+...}, at: [<c054bc08>] clk_prepare_lock+0x10/0xf8
stack backtrace:
CPU: 2 PID: 6 Comm: kworker/u8:0 Not tainted 4.2.0-next-20150908 #1
Hardware name: NVIDIA Tegra SoC (Flattened Device Tree)
Workqueue: deferwq deferred_probe_work_func
[<c001802c>] (unwind_backtrace) from [<c00135a4>] (show_stack+0x10/0x14)
[<c00135a4>] (show_stack) from [<c02a8418>] (dump_stack+0x94/0xd4)
[<c02a8418>] (dump_stack) from [<c03c6f6c>] (dev_pm_opp_find_freq_ceil+0x108/0x114)
[<c03c6f6c>] (dev_pm_opp_find_freq_ceil) from [<c0551a3c>] (dfll_calculate_rate_request+0xb8/0x170)
[<c0551a3c>] (dfll_calculate_rate_request) from [<c0551b10>] (dfll_clk_round_rate+0x1c/0x2c)
[<c0551b10>] (dfll_clk_round_rate) from [<c054de2c>] (clk_calc_new_rates+0x1b8/0x228)
[<c054de2c>] (clk_calc_new_rates) from [<c054e44c>] (clk_core_set_rate_nolock+0x44/0xac)
[<c054e44c>] (clk_core_set_rate_nolock) from [<c054e4d8>] (clk_set_rate+0x24/0x34)
[<c054e4d8>] (clk_set_rate) from [<c0512460>] (tegra124_cpufreq_probe+0x120/0x230)
[<c0512460>] (tegra124_cpufreq_probe) from [<c03b9cbc>] (platform_drv_probe+0x44/0xac)
[<c03b9cbc>] (platform_drv_probe) from [<c03b84c8>] (driver_probe_device+0x218/0x304)
[<c03b84c8>] (driver_probe_device) from [<c03b69b0>] (bus_for_each_drv+0x60/0x94)
[<c03b69b0>] (bus_for_each_drv) from [<c03b8228>] (__device_attach+0xb4/0x118)
ata1: SATA link down (SStatus 0 SControl 300)
[<c03b8228>] (__device_attach) from [<c03b77c8>] (bus_probe_device+0x88/0x90)
[<c03b77c8>] (bus_probe_device) from [<c03b7be8>] (deferred_probe_work_func+0x58/0x8c)
[<c03b7be8>] (deferred_probe_work_func) from [<c0040dfc>] (process_one_work+0x188/0x4bc)
[<c0040dfc>] (process_one_work) from [<c004117c>] (worker_thread+0x4c/0x4f4)
[<c004117c>] (worker_thread) from [<c0047230>] (kthread+0xe4/0xf8)
[<c0047230>] (kthread) from [<c000f7d0>] (ret_from_fork+0x14/0x24)
Signed-off-by: Thierry Reding <treding@nvidia.com>
Fixes: c4fe70ada4 ("clk: tegra: Add closed loop support for the DFLL")
[vince.h@nvidia.com: Unlock rcu on error path]
Signed-off-by: Vince Hsu <vince.h@nvidia.com>
[sboyd@codeaurora.org: Dropped second hunk that nested the rcu
read lock unnecessarily]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
The new determine_rate prototype allows for clock rates exceeding
2^31-1 Hz to be used. Switch the DFLL clock to use determine_rate
instead of round_rate and unlock the top rates supported by the
Tegra124.
Signed-off-by: Mikko Perttunen <mikko.perttunen@kapsi.fi>
Signed-off-by: Thierry Reding <treding@nvidia.com>
The latest Tegra clk pull had some problems. Fix them.
drivers/clk/tegra/clk-tegra124.c:1450:6: warning: symbol 'tegra124_clock_assert_dfll_dvco_reset' was not declared. Should it be static?
drivers/clk/tegra/clk-tegra124.c:1466:6: warning: symbol 'tegra124_clock_deassert_dfll_dvco_reset' was not declared. Should it be static?
drivers/clk/tegra/clk-tegra124.c:1476:5: warning: symbol 'tegra124_reset_assert' was not declared. Should it be static?
drivers/clk/tegra/clk-tegra124.c:1486:5: warning: symbol 'tegra124_reset_deassert' was not declared. Should it be static?
drivers/clk/tegra/clk-dfll.c:590 dfll_load_i2c_lut() warn: inconsistent indenting
drivers/clk/tegra/clk-dfll.c:1448 dfll_build_i2c_lut() warn: unsigned 'td->i2c_lut[0]' is never less than zero.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Add basic platform driver support for the fast CPU cluster DFLL
clocksource found on Tegra124 SoCs. This small driver selects the
appropriate Tegra124-specific characterization data and integration
code. It relies on the DFLL common code to do most of the work.
Signed-off-by: Tuomas Tynkkynen <ttynkkynen@nvidia.com>
Signed-off-by: Mikko Perttunen <mikko.perttunen@kapsi.fi>
Acked-by: Michael Turquette <mturquette@linaro.org>
[treding@nvidia.com: move setup code into ->probe()]
Signed-off-by: Thierry Reding <treding@nvidia.com>
With closed loop support, the clock rate of the DFLL can be adjusted.
The oscillator itself in the DFLL is a free-running oscillator whose
rate is directly determined the supply voltage. However, the DFLL
module contains logic to compare the DFLL output rate to a fixed
reference clock (51 MHz) and make a decision to either lower or raise
the DFLL supply voltage. The DFLL module can then autonomously change
the supply voltage by communicating with an off-chip PMIC via either I2C
or PWM signals. This driver currently supports only I2C.
Signed-off-by: Tuomas Tynkkynen <ttynkkynen@nvidia.com>
Signed-off-by: Mikko Perttunen <mikko.perttunen@kapsi.fi>
Acked-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Acked-by: Michael Turquette <mturquette@linaro.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Add shared code to support the Tegra DFLL clocksource in open-loop
mode. This root clocksource is present on the Tegra124 SoCs. The
DFLL is the intended primary clock source for the fast CPU cluster.
This code is very closely based on a patch by Paul Walmsley from
December (http://comments.gmane.org/gmane.linux.ports.tegra/15273),
which in turn comes from the internal driver by originally created
by Aleksandr Frid <afrid@nvidia.com>.
Subsequent patches will add support for closed loop mode and drivers
for the Tegra124 fast CPU cluster DFLL devices, which rely on this
code.
Signed-off-by: Paul Walmsley <pwalmsley@nvidia.com>
Signed-off-by: Tuomas Tynkkynen <ttynkkynen@nvidia.com>
Signed-off-by: Mikko Perttunen <mikko.perttunen@kapsi.fi>
Acked-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Acked-by: Michael Turquette <mturquette@linaro.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
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