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path: root/drivers/clk/at91/clk-master.c
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2023-06-21clk: at91: clk-master: add support for parent_hwClaudiu Beznea1-9/+19
Add support for parent_hw in master clock drivers. With this parent-child relation is described with pointers rather than strings making registration a bit faster. All the SoC based drivers that rely on clk-master were adapted to the new API change. The switch itself for SoCs will be done in subsequent patches. Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> Reviewed-by: Maxime Ripard <mripard@kernel.org> Link: https://lore.kernel.org/r/20230615093227.576102-4-claudiu.beznea@microchip.com
2022-09-15clk: Stop forwarding clk_rate_requests to the parentMaxime Ripard1-3/+6
If the clock cannot modify its rate and has CLK_SET_RATE_PARENT, clk_mux_determine_rate_flags(), clk_core_round_rate_nolock() and a number of drivers will forward the clk_rate_request to the parent clock. clk_core_round_rate_nolock() will pass the pointer directly, which means that we pass a clk_rate_request to the parent that has the rate, min_rate and max_rate of the child, and the best_parent_rate and best_parent_hw fields will be relative to the child as well, so will point to our current clock and its rate. The most common case for CLK_SET_RATE_PARENT is that the child and parent clock rates will be equal, so the rate field isn't a worry, but the other fields are. Similarly, if the parent clock driver ever modifies the best_parent_rate or best_parent_hw, this will be applied to the child once the call to clk_core_round_rate_nolock() is done. best_parent_hw is probably not going to be a valid parent, and best_parent_rate might lead to a parent rate change different to the one that was initially computed. clk_mux_determine_rate_flags() and the affected drivers will copy the request before forwarding it to the parents, so they won't be affected by the latter issue, but the former is still going to be there and will lead to erroneous data and context being passed to the various clock drivers in the same sub-tree. Let's create two new functions, clk_core_forward_rate_req() and clk_hw_forward_rate_request() for the framework and the clock providers that will copy a request from a child clock and update the context to match the parent's. We also update the relevant call sites in the framework and drivers to use that new function. Let's also add a test to make sure we avoid regressions there. Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com> # imx8mp Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> # exynos4210, meson g12b Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20220816112530.1837489-22-maxime@cerno.tech Tested-by: Linux Kernel Functional Testing <lkft@linaro.org> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-03-08clk: at91: clk-master: remove dead codeClaudiu Beznea1-111/+6
Commit facb87ad7560 ("clk: at91: sama7g5: remove prescaler part of master clock") removed the master clock's prescaler from clock tree of SAMA7G5 as it has been discovered that there is a hardware bug when trying to change it at run-time (bug is described in description of commit facb87ad7560 ("clk: at91: sama7g5: remove prescaler part of master clock")). This was previously changed at CPUFreq driver request. Thus, with commit facb87ad7560 ("clk: at91: sama7g5: remove prescaler part of master clock") there is no need of code that handles run-time changes of master clock's prescaler, thus remove this code. Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com> Link: https://lore.kernel.org/r/20220203110202.18329-1-claudiu.beznea@microchip.com
2021-10-27clk: at91: clk-master: add notifier for dividerClaudiu Beznea1-70/+174
SAMA7G5 supports DVFS by changing cpuck. On SAMA7G5 mck0 shares the same parent with cpuck as seen in the following clock tree: +----------> cpuck | FRAC PLL ---> DIV PLL -+-> DIV ---> mck0 mck0 could go b/w 32KHz and 200MHz on SAMA7G5. To avoid mck0 overclocking while changing FRAC PLL or DIV PLL the commit implements a notifier for mck0 which applies a safe divider to register (maximum value of the divider which is 5) on PRE_RATE_CHANGE events (such that changes on PLL to not overclock mck0) and sets the maximum allowed rate on POST_RATE_CHANGE events. Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> Link: https://lore.kernel.org/r/20211011112719.3951784-13-claudiu.beznea@microchip.com Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2021-10-27clk: at91: clk-master: fix prescaler logicClaudiu Beznea1-1/+1
When prescaler value read from register is MASTER_PRES_MAX it means that the input clock will be divided by 3. Fix the code to reflect this. Fixes: 7a110b9107ed8 ("clk: at91: clk-master: re-factor master clock") Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> Link: https://lore.kernel.org/r/20211011112719.3951784-11-claudiu.beznea@microchip.com Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2021-10-27clk: at91: clk-master: mask mckr against layout->maskClaudiu Beznea1-2/+5
Mask values read/written from/to MCKR against layout->mask as this mask may be different b/w PMC versions. Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> Link: https://lore.kernel.org/r/20211011112719.3951784-10-claudiu.beznea@microchip.com Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2021-10-27clk: at91: clk-master: check if div or pres is zeroClaudiu Beznea1-2/+2
Check if div or pres is zero before using it as argument for ffs(). In case div is zero ffs() will return 0 and thus substracting from zero will lead to invalid values to be setup in registers. Fixes: 7a110b9107ed8 ("clk: at91: clk-master: re-factor master clock") Fixes: 75c88143f3b87 ("clk: at91: clk-master: add master clock support for SAMA7G5") Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> Link: https://lore.kernel.org/r/20211011112719.3951784-9-claudiu.beznea@microchip.com Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2021-10-27clk: at91: clk-master: improve readability by using local variablesClaudiu Beznea1-3/+3
Improve readability in clk_sama7g5_master_set() by using local variables. Suggested-by: Nicolas Ferre <nicolas.ferre@microchip.com> Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> Link: https://lore.kernel.org/r/20211011112719.3951784-6-claudiu.beznea@microchip.com Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2021-10-27clk: at91: clk-master: add register definition for sama7g5's master clockClaudiu Beznea1-27/+23
SAMA7G5 has 4 master clocks (MCK1..4) which are controlled though the register at offset 0x30 (relative to PMC). In the last/first phase of suspend/resume procedure (which is architecture specific) the parent of master clocks are changed (via assembly code) for more power saving (see file arch/arm/mach-at91/pm_suspend.S, macros at91_mckx_ps_enable and at91_mckx_ps_restore). Thus the macros corresponding to register at offset 0x30 need to be shared b/w clk-master.c and pm_suspend.S. commit ec03f18cc222 ("clk: at91: add register definition for sama7g5's master clock") introduced the proper macros but didn't adapted the clk-master.c as well. Thus, this commit adapt the clk-master.c to use the macros introduced in commit ec03f18cc222 ("clk: at91: add register definition for sama7g5's master clock"). Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> Link: https://lore.kernel.org/r/20211011112719.3951784-5-claudiu.beznea@microchip.com Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2021-10-27clk: at91: re-factor clocks suspend/resumeClaudiu Beznea1-12/+182
SAMA5D2 and SAMA7G5 have a special power saving mode (backup mode) where most of the SoC's components are powered off (including PMC). Resuming from this mode is done with the help of bootloader. Peripherals are not aware of the power saving mode thus most of them are disabling clocks in proper suspend API and re-enable them in resume API without taking into account the previously setup rate. Moreover some of the peripherals are acting as wakeup sources and are not disabling the clocks in this scenario, when suspending. Since backup mode cuts the power for peripherals, in resume part these clocks needs to be re-configured. The initial PMC suspend/resume code was designed only for SAMA5D2's PMC (as it was the only one supporting backup mode). SAMA7G supports also backup mode and its PMC is different (few new functionalities, different registers offsets, different offsets in registers for each functionalities). To address both SAMA5D2 and SAMA7G5 PMC add .save_context()/.resume_context() support to each clocks driver and call this from PMC driver. Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> Link: https://lore.kernel.org/r/20211011112719.3951784-2-claudiu.beznea@microchip.com Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2020-12-19clk: at91: clk-master: re-factor master clockClaudiu Beznea1-45/+290
Re-factor master clock driver by splitting it into 2 clocks: prescaller and divider clocks. Based on registered clock flags the prescaler's rate could be changed at runtime. This is necessary for platforms supporting DVFS (e.g. SAMA7G5) where master clock could be changed at run-time. Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> Link: https://lore.kernel.org/r/1605800597-16720-11-git-send-email-claudiu.beznea@microchip.com Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2020-12-19clk: at91: clk-master: add 5th divisor for mck masterEugen Hristev1-1/+1
clk-master can have 5 divisors with a field width of 3 bits on some products. Change the mask and number of divisors accordingly. Reported-by: Mihai Sain <mihai.sain@microchip.com> Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com> Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> Link: https://lore.kernel.org/r/1605800597-16720-5-git-send-email-claudiu.beznea@microchip.com Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2020-07-24clk: at91: clk-master: add master clock support for SAMA7G5Claudiu Beznea1-5/+305
Add master clock support (MCK1..4) for SAMA7G5. SAMA7G5's PMC has multiple master clocks feeding different subsystems. One of them feeds image subsystem and is changeable based on image subsystem needs. Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> Link: https://lore.kernel.org/r/1595403506-8209-13-git-send-email-claudiu.beznea@microchip.com Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2020-07-24clk: at91: replace conditional operator with double logical notClaudiu Beznea1-1/+1
Replace conditional operator with double logical not as code may be simpler to read. Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> Link: https://lore.kernel.org/r/1595403506-8209-10-git-send-email-claudiu.beznea@microchip.com Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner1-6/+1
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 as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25clk: at91: master: Add sam9x60 supportAlexandre Belloni1-3/+5
The sam9x60 cpu clock is located at a different offset but is otherwise similar to the master clock. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2018-10-17clk: at91: move DT compatibility code to its own fileAlexandre Belloni1-82/+0
Move all the DT backward compatibility code to its own file so it can be deleted later. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2018-10-17clk: at91: allow clock registration from C codeAlexandre Belloni1-14/+3
Remove static keyword to allow functions to be used from other units. Also move some struct and function declarations to pmc.h Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> [sboyd@kernel.org: Include pmc.h] Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2016-09-15clk: at91: Migrate to clk_hw based registration and OF APIsStephen Boyd1-9/+12
Now that we have clk_hw based provider APIs to register clks, we can get rid of struct clk pointers in this driver, allowing us to move closer to a clear split of consumer and provider clk APIs. Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org> Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Tested-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-03-23Merge tag 'clk-for-linus' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux Pull clk updates from Stephen Boyd: "The clk changes for this release cycle are mostly dominated by new device support in terms of LoC, but there has been some cleanup in the core as well as the usual minor clk additions to various drivers. Core: - parent tracking has been simplified - CLK_IS_ROOT is now a no-op flag, cleaning up drivers has started - of_clk_init() doesn't consider disabled DT nodes anymore - clk_unregister() had an error path bug squashed - of_clk_get_parent_count() has been fixed to only return unsigned ints - HAVE_MACH_CLKDEV is removed now that the last arch user (ARM) is gone New Drivers: - NXP LPC18xx creg - QCOM IPQ4019 GCC - TI dm814x ADPLL - i.MX6QP Updates: - Cyngus audio clks found on Broadcom iProc devices - Non-critical fixes for BCM2385 PLLs - Samsung exynos5433 updates for clk id errors, HDMI support, suspend/resume simplifications - USB, CAN, LVDS, and FCP clks on shmobile devices - sunxi got support for more clks on new SoCs and went through a minor refactoring/rewrite to use a simpler factor clk construct - rockchip added some more clk ids and added suport for fraction dividers - QCOM GDSCs in msm8996 - A new devm helper to make adding custom actions simpler (acked by Greg)" * tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (197 commits) clk: bcm2835: fix check of error code returned by devm_ioremap_resource() clk: renesas: div6: use RENESAS for #define clk: renesas: Rename header file renesas.h clk: max77{686,802}: Remove CLK_IS_ROOT clk: versatile: Remove CLK_IS_ROOT clk: sunxi: Remove use of variable length array clk: fixed-rate: Remove CLK_IS_ROOT clk: qcom: Remove CLK_IS_ROOT doc: dt: add documentation for lpc1850-creg-clk driver clk: add lpc18xx creg clk driver clk: lpc32xx: fix compilation warning clk: xgene: Add missing parenthesis when clearing divider value clk: mb86s7x: Remove CLK_IS_ROOT clk: x86: Remove clkdev.h and clk.h includes clk: x86: Remove CLK_IS_ROOT clk: mvebu: Remove CLK_IS_ROOT clk: renesas: move drivers to renesas directory clk: si5{14,351,70}: Remove CLK_IS_ROOT clk: scpi: Remove CLK_IS_ROOT clk: s2mps11: Remove CLK_IS_ROOT ...
2016-02-27clk: at91: Remove impossible checks for of_clk_get_parent_count()Stephen Boyd1-2/+2
These checks for < 0 are impossible now that of_clk_get_parent_count() returns an unsigned int. Change the checks for == 0 and update the type. Cc: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-02-17clk: at91: remove IRQ handling and use pollingAlexandre Belloni1-42/+4
The AT91 clock drivers make use of IRQs to avoid polling when waiting for some clocks to be enabled. Unfortunately, this leads to a crash when those IRQs are threaded (which happens when using preempt-rt) because they are registered before thread creation is possible. Use polling on those clocks instead to avoid the problem. Acked-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-02-17clk: at91: make use of syscon/regmap internallyBoris Brezillon1-25/+43
Use the regmap coming from syscon to access the registers instead of using pmc_read/pmc_write. This allows to avoid passing the at91_pmc structure to the child nodes of the PMC. The final benefit is to have each clock register itself instead of having to iterate over the children. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Acked-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-07-28clk: at91: make use of of_clk_parent_fill helper functionDinh Nguyen1-6/+1
Use of_clk_parent_fill to fill in the parent clock names' array. Signed-off-by: Dinh Nguyen <dinguyen@opensource.altera.com> Cc: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-07-02clk: at91: do not leak resourcesDavid Dueck1-2/+6
Do not leak memory and free irqs in case of an error. Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: David Dueck <davidcdueck@googlemail.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-06-04clk: at91: Use of_clk_get_parent_count() instead of open codingGeert Uytterhoeven1-1/+1
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2014-02-27clk:at91: Fix memory leak in of_at91_clk_master_setup()Masanari Iida1-1/+1
cppcheck detected following error [clk-master.c:245]: (error) Memory leak: characteristics The original code forgot to free characteristics when irq_of_parse_and_map() failed. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by Boris BREZILLON <b.brezillon@overkiz.com> Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Signed-off-by: Mike Turquette <mturquette@linaro.org>
2013-12-02clk: at91: add PMC master clockBoris BREZILLON1-0/+270
This patch adds new at91 master clock implementation using common clk framework. The master clock layout describe the MCKR register layout. There are 2 master clock layouts: - at91rm9200 - at91sam9x5 Master clocks are given characteristics: - min/max clock output rate These characteristics are checked during rate change to avoid over/underclocking. These characteristics are described in atmel's SoC datasheet in "Electrical Characteristics" paragraph. Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com> Acked-by: Mike Turquette <mturquette@linaro.org> Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>