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2021-10-20clk: socfpga: agilex: fix duplicate s2f_user0_clkDinh Nguyen1-9/+0
commit 09540fa337196be20e9f0241652364f09275d374 upstream. Remove the duplicate s2f_user0_clk and the unused s2f_usr0_mux define. Fixes: f817c132db67 ("clk: socfpga: agilex: fix up s2f_user0_clk representation") Cc: stable@vger.kernel.org Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> Link: https://lore.kernel.org/r/20210916225126.1427700-1-dinguyen@kernel.org Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-30treewide: Change list_sort to use const pointersSami Tolvanen1-2/+2
[ Upstream commit 4f0f586bf0c898233d8f316f471a21db2abd522d ] list_sort() internally casts the comparison function passed to it to a different type with constant struct list_head pointers, and uses this pointer to call the functions, which trips indirect call Control-Flow Integrity (CFI) checking. Instead of removing the consts, this change defines the list_cmp_func_t type and changes the comparison function types of all list_sort() callers to use const pointers, thus avoiding type mismatches. Suggested-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Sami Tolvanen <samitolvanen@google.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Kees Cook <keescook@chromium.org> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210408182843.1754385-10-samitolvanen@google.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-18clk: at91: clk-generated: Limit the requested rate to our rangeCodrin Ciubotariu1-0/+6
[ Upstream commit af7651e67b9d5f7e63ea23b118e3672ac662244a ] On clk_generated_determine_rate(), the requested rate could be outside of clk's range. Limit the rate to the clock's range to not return an error. Fixes: df70aeef6083 ("clk: at91: add generated clock driver") Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com> Link: https://lore.kernel.org/r/20210707131213.3283509-1-codrin.ciubotariu@microchip.com Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com> Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-18clk: imx8m: fix clock tree update of TF-A managed clocksAhmad Fatoum5-12/+28
[ Upstream commit d36207b848a6490e14664e2197a1c8ab51d8148e ] On the i.MX8M*, the TF-A exposes a SiP (Silicon Provider) service for DDR frequency scaling. The imx8m-ddrc-devfreq driver calls the SiP and then does clk_set_parent on the DDR muxes to synchronize the clock tree. Since 936c383673b9 ("clk: imx: fix composite peripheral flags"), these TF-A managed muxes have SET_PARENT_GATE set, which results in imx8m-ddrc-devfreq's clk_set_parent after SiP failing with -EBUSY: echo 25000000 > userspace/set_freq imx8m-ddrc-devfreq 3d400000.memory-controller: failed to set dram_apb parent: -16 Fix this by adding a new i.MX composite flag for firmware managed clocks, which clears SET_PARENT_GATE. This is safe to do, because updating the Linux clock tree to reflect reality will always be glitch-free. Fixes: 936c383673b9 ("clk: imx: fix composite peripheral flags") Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de> Reviewed-by: Abel Vesa <abel.vesa@nxp.com> Link: https://lore.kernel.org/r/20210810151432.9228-1-a.fatoum@pengutronix.de Signed-off-by: Abel Vesa <abel.vesa@nxp.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-18clk: rockchip: drop GRF dependency for rk3328/rk3036 pll typesPeter Geis1-1/+1
[ Upstream commit 6fffe52fb336ec2063270a7305652a93ea677ca1 ] The rk3036/rk3328 pll types were converted to checking the lock status via the internal register in january 2020, so don't need the grf reference since then. But it was forgotten to remove grf check when deciding between the pll rate ops (read-only vs. read-write), so a clock driver without the needed grf reference might've been put into the read-only mode just because the grf reference was missing. This affected the rk356x that needs to reclock certain plls at boot. Fix this by removing the check for the grf for selecting the utilized operations. Suggested-by: Heiko Stuebner <heiko@sntech.de> Fixes: 7f6ffbb885d1 ("clk: rockchip: convert rk3036 pll type to use internal lock status") Signed-off-by: Peter Geis <pgwipeout@gmail.com> [adjusted the commit message, adjusted the fixes tag] Link: https://lore.kernel.org/r/20210728180034.717953-3-pgwipeout@gmail.com Signed-off-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-18clk: socfpga: agilex: add the bypass register for s2f_usr0 clockDinh Nguyen1-1/+1
commit d17929eb1066d1c1653aae9bb4396a9f1d6602ac upstream. Add the bypass register for the s2f_user0_clk. Fixes: 80c6b7a0894f ("clk: socfpga: agilex: add clock driver for the Agilex platform") Cc: stable@vger.kernel.org Signed-off-by: Kris Chaplin <kris.chaplin@intel.com> Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> Link: https://lore.kernel.org/r/20210713144621.605140-3-dinguyen@kernel.org Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-18clk: socfpga: agilex: fix up s2f_user0_clk representationDinh Nguyen1-0/+9
commit f817c132db679d492d96c60993fa2f2c67ab18d0 upstream. Correct the s2f_user0_mux clock representation. Fixes: 80c6b7a0894f ("clk: socfpga: agilex: add clock driver for the Agilex platform") Cc: stable@vger.kernel.org Signed-off-by: Kris Chaplin <kris.chaplin@intel.com> Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> Link: https://lore.kernel.org/r/20210713144621.605140-2-dinguyen@kernel.org Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-18clk: socfpga: agilex: fix the parents of the psi_ref_clkDinh Nguyen1-4/+4
commit 9d563236cca43fc4fe190b3be173444bd48e2a3b upstream. The psi_ref_clk comes from the C2 node of the main_pll and periph_pll, not the C3. Fixes: 80c6b7a0894f ("clk: socfpga: agilex: add clock driver for the Agilex platform") Cc: stable@vger.kernel.org Signed-off-by: Kris Chaplin <kris.chaplin@intel.com> Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> Link: https://lore.kernel.org/r/20210713144621.605140-1-dinguyen@kernel.org Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-15clk: kirkwood: Fix a clocking boot regressionLinus Walleij1-0/+1
commit aaedb9e00e5400220a8871180d23a83e67f29f63 upstream. Since a few kernel releases the Pogoplug 4 has crashed like this during boot: Unable to handle kernel NULL pointer dereference at virtual address 00000002 (...) [<c04116ec>] (strlen) from [<c00ead80>] (kstrdup+0x1c/0x4c) [<c00ead80>] (kstrdup) from [<c04591d8>] (__clk_register+0x44/0x37c) [<c04591d8>] (__clk_register) from [<c04595ec>] (clk_hw_register+0x20/0x44) [<c04595ec>] (clk_hw_register) from [<c045bfa8>] (__clk_hw_register_mux+0x198/0x1e4) [<c045bfa8>] (__clk_hw_register_mux) from [<c045c050>] (clk_register_mux_table+0x5c/0x6c) [<c045c050>] (clk_register_mux_table) from [<c0acf3e0>] (kirkwood_clk_muxing_setup.constprop.0+0x13c/0x1ac) [<c0acf3e0>] (kirkwood_clk_muxing_setup.constprop.0) from [<c0aceae0>] (of_clk_init+0x12c/0x214) [<c0aceae0>] (of_clk_init) from [<c0ab576c>] (time_init+0x20/0x2c) [<c0ab576c>] (time_init) from [<c0ab3d18>] (start_kernel+0x3dc/0x56c) [<c0ab3d18>] (start_kernel) from [<00000000>] (0x0) Code: e3130020 1afffffb e12fff1e c08a1078 (e5d03000) This is because the "powersave" mux clock 0 was provided in an unterminated array, which is required by the loop in the driver: /* Count, allocate, and register clock muxes */ for (n = 0; desc[n].name;) n++; Here n will go out of bounds and then call clk_register_mux() on random memory contents after the mux clock. Fix this by terminating the array with a blank entry. Fixes: 105299381d87 ("cpufreq: kirkwood: use the powersave multiplexer") Cc: stable@vger.kernel.org Cc: Andrew Lunn <andrew@lunn.ch> Cc: Chris Packham <chris.packham@alliedtelesis.co.nz> Cc: Gregory CLEMENT <gregory.clement@bootlin.com> Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20210814235514.403426-1-linus.walleij@linaro.org Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-03clk: renesas: rcar-usb2-clock-sel: Fix kernel NULL pointer dereferenceAdam Ford1-1/+1
[ Upstream commit 1669a941f7c4844ae808cf441db51dde9e94db07 ] The probe was manually passing NULL instead of dev to devm_clk_hw_register. This caused a Unable to handle kernel NULL pointer dereference error. Fix this by passing 'dev'. Signed-off-by: Adam Ford <aford173@gmail.com> Fixes: a20a40a8bbc2 ("clk: renesas: rcar-usb2-clock-sel: Fix error handling in .probe()") Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-08-26clk: qcom: gdsc: Ensure regulator init state matches GDSC stateBjorn Andersson1-18/+36
[ Upstream commit 9711759a87a041705148161b937ec847048d882e ] As GDSCs are registered and found to be already enabled gdsc_init() ensures that 1) the kernel state matches the hardware state, and 2) votable GDSCs are properly enabled from this master as well. But as the (optional) supply regulator is enabled deep into gdsc_toggle_logic(), which is only executed for votable GDSCs, the kernel's state of the regulator might not match the hardware. The regulator might be automatically turned off if no other users are present or the next call to gdsc_disable() would cause an unbalanced regulator_disable(). Given that the votable case deals with an already enabled GDSC, most of gdsc_enable() and gdsc_toggle_logic() can be skipped. Reduce it to just clearing the SW_COLLAPSE_MASK and enabling hardware control to simply call regulator_enable() in both cases. The enablement of hardware control seems to be an independent property from the GDSC being enabled, so this is moved outside that conditional segment. Lastly, as the propagation of ALWAYS_ON to GENPD_FLAG_ALWAYS_ON needs to happen regardless of the initial state this is grouped together with the other sc->pd updates at the end of the function. Cc: stable@vger.kernel.org Fixes: 37416e554961 ("clk: qcom: gdsc: Handle GDSC regulator supplies") Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> Link: https://lore.kernel.org/r/20210721224056.3035016-1-bjorn.andersson@linaro.org [sboyd@kernel.org: Rephrase commit text] Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-08-26clk: imx6q: fix uart earlycon unworkDong Aisheng1-1/+1
[ Upstream commit 283f1b9a0401859c53fdd6483ab66f1c4fadaea5 ] The earlycon depends on the bootloader setup UART clocks being retained. There're actually two uart clocks (ipg, per) on MX6QDL, but the 'Fixes' commit change to register only one which means another clock may be disabled during booting phase and result in the earlycon unwork. Cc: stable@vger.kernel.org # v5.10+ Fixes: 379c9a24cc23 ("clk: imx: Fix reparenting of UARTs not associated with stdout") Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com> Link: https://lore.kernel.org/r/20210702085438.1988087-1-aisheng.dong@nxp.com Reviewed-by: Abel Vesa <abel.vesa@nxp.com> Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-08-12clk: fix leak on devm_clk_bulk_get_all() unwindBrian Norris1-1/+8
commit f828b0bcacef189edbd247e9f48864fc36bfbe33 upstream. clk_bulk_get_all() allocates an array of struct clk_bulk data for us (unlike clk_bulk_get()), so we need to free it. Let's use the clk_bulk_put_all() helper. kmemleak complains, on an RK3399 Gru/Kevin system: unreferenced object 0xffffff80045def00 (size 128): comm "swapper/0", pid 1, jiffies 4294667682 (age 86.394s) hex dump (first 32 bytes): 44 32 60 fe fe ff ff ff 00 00 00 00 00 00 00 00 D2`............. 48 32 60 fe fe ff ff ff 00 00 00 00 00 00 00 00 H2`............. backtrace: [<00000000742860d6>] __kmalloc+0x22c/0x39c [<00000000b0493f2c>] clk_bulk_get_all+0x64/0x188 [<00000000325f5900>] devm_clk_bulk_get_all+0x58/0xa8 [<00000000175b9bc5>] dwc3_probe+0x8ac/0xb5c [<000000009169e2f9>] platform_drv_probe+0x9c/0xbc [<000000005c51e2ee>] really_probe+0x13c/0x378 [<00000000c47b1f24>] driver_probe_device+0x84/0xc0 [<00000000f870fcfb>] __device_attach_driver+0x94/0xb0 [<000000004d1b92ae>] bus_for_each_drv+0x8c/0xd8 [<00000000481d60c3>] __device_attach+0xc4/0x150 [<00000000a163bd36>] device_initial_probe+0x1c/0x28 [<00000000accb6bad>] bus_probe_device+0x3c/0x9c [<000000001a199f89>] device_add+0x218/0x3cc [<000000001bd84952>] of_device_add+0x40/0x50 [<000000009c658c29>] of_platform_device_create_pdata+0xac/0x100 [<0000000021c69ba4>] of_platform_bus_create+0x190/0x224 Fixes: f08c2e2865f6 ("clk: add managed version of clk_bulk_get_all") Cc: Dong Aisheng <aisheng.dong@nxp.com> Cc: stable@vger.kernel.org Signed-off-by: Brian Norris <briannorris@chromium.org> Link: https://lore.kernel.org/r/20210731025950.2238582-1-briannorris@chromium.org Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12clk: tegra: Implement disable_unused() of tegra_clk_sdmmc_mux_opsDmitry Osipenko1-0/+10
[ Upstream commit 2bcc025ab9bbd029b1730cde71cb4e4f0ed35d0f ] Implement disable_unused() callback of tegra_clk_sdmmc_mux_ops to fix imbalanced disabling of the unused MMC clock on Tegra210 Jetson Nano. Fixes: c592c8a28f58 ("clk: tegra: Fix refcounting of gate clocks") Reported-by: Jon Hunter <jonathanh@nvidia.com> # T210 Nano Tested-by: Jon Hunter <jonathanh@nvidia.com> # T210 Nano Acked-by: Jon Hunter <jonathanh@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Link: https://lore.kernel.org/r/20210717112742.7196-1-digetx@gmail.com Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-08-12clk: stm32f4: fix post divisor setup for I2S/SAI PLLsDario Binacchi1-5/+5
[ Upstream commit 24b5b1978cd5a80db58e2a19db2f9c36fe8d4f7a ] Enabling the framebuffer leads to a system hang. Running, as a debug hack, the store_pan() function in drivers/video/fbdev/core/fbsysfs.c without taking the console_lock, allows to see the crash backtrace on the serial line. ~ # echo 0 0 > /sys/class/graphics/fb0/pan [ 9.719414] Unhandled exception: IPSR = 00000005 LR = fffffff1 [ 9.726937] CPU: 0 PID: 49 Comm: sh Not tainted 5.13.0-rc5 #9 [ 9.733008] Hardware name: STM32 (Device Tree Support) [ 9.738296] PC is at clk_gate_is_enabled+0x0/0x28 [ 9.743426] LR is at stm32f4_pll_div_set_rate+0xf/0x38 [ 9.748857] pc : [<0011e4be>] lr : [<0011f9e3>] psr: 0100000b [ 9.755373] sp : 00bc7be0 ip : 00000000 fp : 001f3ac4 [ 9.760812] r10: 002610d0 r9 : 01efe920 r8 : 00540560 [ 9.766269] r7 : 02e7ddb0 r6 : 0173eed8 r5 : 00000000 r4 : 004027c0 [ 9.773081] r3 : 0011e4bf r2 : 02e7ddb0 r1 : 0173eed8 r0 : 1d3267b8 [ 9.779911] xPSR: 0100000b [ 9.782719] CPU: 0 PID: 49 Comm: sh Not tainted 5.13.0-rc5 #9 [ 9.788791] Hardware name: STM32 (Device Tree Support) [ 9.794120] [<0000afa1>] (unwind_backtrace) from [<0000a33f>] (show_stack+0xb/0xc) [ 9.802421] [<0000a33f>] (show_stack) from [<0000a8df>] (__invalid_entry+0x4b/0x4c) The `pll_num' field in the post_div_data configuration contained a wrong value which also referenced an uninitialized hardware clock when clk_register_pll_div() was called. Fixes: 517633ef630e ("clk: stm32f4: Add post divisor for I2S & SAI PLLs") Signed-off-by: Dario Binacchi <dariobin@libero.it> Reviewed-by: Gabriel Fernandez <gabriel.fernandez@st.com> Link: https://lore.kernel.org/r/20210725160725.10788-1-dariobin@libero.it Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-19clk: tegra: Ensure that PLLU configuration is applied properlyDmitry Osipenko1-5/+4
[ Upstream commit a7196048cd5168096c2c4f44a3939d7a6dcd06b9 ] The PLLU (USB) consists of the PLL configuration itself and configuration of the PLLU outputs. The PLLU programming is inconsistent on T30 vs T114, where T114 immediately bails out if PLLU is enabled and T30 re-enables a potentially already enabled PLL (left after bootloader) and then fully reprograms it, which could be unsafe to do. The correct way should be to skip enabling of the PLL if it's already enabled and then apply configuration to the outputs. This patch doesn't fix any known problems, it's a minor improvement. Acked-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-19clk: tegra: Fix refcounting of gate clocksDmitry Osipenko2-25/+58
[ Upstream commit c592c8a28f5821e880ac6675781cd8a151b0737c ] The refcounting of the gate clocks has a bug causing the enable_refcnt to underflow when unused clocks are disabled. This happens because clk provider erroneously bumps the refcount if clock is enabled at a boot time, which it shouldn't be doing, and it does this only for the gate clocks, while peripheral clocks are using the same gate ops and the peripheral clocks are missing the initial bump. Hence the refcount of the peripheral clocks is 0 when unused clocks are disabled and then the counter is decremented further by the gate ops, causing the integer underflow. Fix this problem by removing the erroneous bump and by implementing the disable_unused() callback, which disables the unused gates properly. The visible effect of the bug is such that the unused clocks are never gated if a loaded kernel module grabs the unused clocks and starts to use them. In practice this shouldn't cause any real problems for the drivers and boards supported by the kernel today. Acked-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-19clk: renesas: r8a77995: Add ZA2 clockKuninori Morimoto1-0/+1
[ Upstream commit 790c06cc5df263cdaff748670cc65958c81b0951 ] R-Car D3 ZA2 clock is from PLL0D3 or S0, and it can be controlled by ZA2CKCR. It is needed for R-Car Sound, but is not used so far. Using default settings is very enough at this point. This patch adds it by DEF_FIXED(). Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> Link: https://lore.kernel.org/r/87pmxclrmy.wl-kuninori.morimoto.gx@renesas.com Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-19clk: renesas: rcar-usb2-clock-sel: Fix error handling in .probe()Dinghao Liu1-9/+15
[ Upstream commit a20a40a8bbc2cf4b29d7248ea31e974e9103dd7f ] The error handling paths after pm_runtime_get_sync() have no refcount decrement, which leads to refcount leak. Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn> Link: https://lore.kernel.org/r/20210415073338.22287-1-dinghao.liu@zju.edu.cn [geert: Remove now unused variable priv] Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-14clk: si5341: Update initialization magicRobert Hancock1-1/+3
[ Upstream commit 3c9b49b0031aefb81adfdba5ab0ddf3ca3a2cdc9 ] Update the default register settings to include the VCO_RESET_CALCODE settings (set by the SiLabs ClockBuilder software but not described in the datasheet). Also update part of the initialization sequence to match ClockBuilder and the datasheet. Fixes: 3044a860fd ("clk: Add Si5341/Si5340 driver") Signed-off-by: Robert Hancock <robert.hancock@calian.com> Link: https://lore.kernel.org/r/20210325192643.2190069-6-robert.hancock@calian.com Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-14clk: si5341: Check for input clock presence and PLL lock on startupRobert Hancock1-0/+26
[ Upstream commit 71dcc4d1f7d2ad97ff7ab831281bc6893ff713a2 ] After initializing the device, wait for it to report that the input clock is present and the PLL has locked before declaring success. Fixes: 3044a860fd ("clk: Add Si5341/Si5340 driver") Signed-off-by: Robert Hancock <robert.hancock@calian.com> Link: https://lore.kernel.org/r/20210325192643.2190069-5-robert.hancock@calian.com Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-14clk: si5341: Avoid divide errors due to bogus register contentsRobert Hancock1-2/+13
[ Upstream commit 78f6f406026d688868223d5dbeb197a4f7e9a9fd ] If the Si5341 is being initially programmed and has no stored NVM configuration, some of the register contents may contain unexpected values, such as zeros, which could cause divide by zero errors during driver initialization. Trap errors caused by zero registers or zero clock rates which could result in divide errors later in the code. Fixes: 3044a860fd ("clk: Add Si5341/Si5340 driver") Signed-off-by: Robert Hancock <robert.hancock@calian.com> Link: https://lore.kernel.org/r/20210325192643.2190069-4-robert.hancock@calian.com Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-14clk: si5341: Wait for DEVICE_READY on startupRobert Hancock1-0/+32
[ Upstream commit 6e7d2de1e000d36990923ed80d2e78dfcb545cee ] The Si5341 datasheet warns that before accessing any other registers, including the PAGE register, we need to wait for the DEVICE_READY register to indicate the device is ready, or the process of the device loading its state from NVM can be corrupted. Wait for DEVICE_READY on startup before continuing initialization. This is done using a raw I2C register read prior to setting up regmap to avoid any potential unwanted automatic PAGE register accesses from regmap at this stage. Fixes: 3044a860fd ("clk: Add Si5341/Si5340 driver") Signed-off-by: Robert Hancock <robert.hancock@calian.com> Link: https://lore.kernel.org/r/20210325192643.2190069-3-robert.hancock@calian.com Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-14clk: qcom: clk-alpha-pll: fix CAL_L write in alpha_pll_fabia_prepareJonathan Marek1-1/+1
[ Upstream commit 7f54bf2640e877c8a9b4cc7e2b29f82e3ca1a284 ] Caught this when looking at alpha-pll code. Untested but it is clear that this was intended to write to PLL_CAL_L_VAL and not PLL_ALPHA_VAL. Fixes: 691865bad627 ("clk: qcom: clk-alpha-pll: Add support for Fabia PLL calibration") Signed-off-by: Jonathan Marek <jonathan@marek.ca> Link: https://lore.kernel.org/r/20210609022852.4151-1-jonathan@marek.ca Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-14clk: actions: Fix AHPPREDIV-H-AHB clock chain on Owl S500 SoCCristian Ciocaltea1-8/+11
[ Upstream commit fd90b5b9045274360b12cea0f2ce50f3bcfb25cc ] There are a few issues with the setup of the Actions Semi Owl S500 SoC's clock chain involving AHPPREDIV, H and AHB clocks: * AHBPREDIV clock is defined as a muxer only, although it also acts as a divider. * H clock is using a wrong divider register offset * AHB is defined as a multi-rate factor clock, but it is actually just a fixed pass clock. Let's provide the following fixes: * Change AHBPREDIV clock to an ungated OWL_COMP_DIV definition. * Use the correct register shift value in the OWL_DIVIDER definition for H clock * Drop the unneeded 'ahb_factor_table[]' and change AHB clock to an ungated OWL_COMP_FIXED_FACTOR definition. Fixes: ed6b4795ece4 ("clk: actions: Add clock driver for S500 SoC") Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@gmail.com> Link: https://lore.kernel.org/r/21c1abd19a7089b65a34852ac6513961be88cbe1.1623354574.git.cristian.ciocaltea@gmail.com Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-14clk: actions: Fix bisp_factor_table based clocks on Owl S500 SoCCristian Ciocaltea1-15/+29
[ Upstream commit a8f1f03caa51aa7a69c671aa87c475034db7d368 ] The following clocks of the Actions Semi Owl S500 SoC have been defined to use a shared clock factor table 'bisp_factor_table[]': DE[1-2], VCE, VDE, BISP, SENSOR[0-1] There are several issues involved in this approach: * 'bisp_factor_table[]' describes the configuration of a regular 8-rates divider, so its usage is redundant. Additionally, judging by the BISP clock context, it is incomplete since it maps only 8 out of 12 possible entries. * The clocks mentioned above are not identical in terms of the available rates, therefore cannot rely on the same factor table. Specifically, BISP and SENSOR* are standard 12-rate dividers so their configuration should rely on a proper clock div table, while VCE and VDE require a factor table that is a actually a subset of the one needed for DE[1-2] clocks. Let's fix this by implementing the following: * Add new factor tables 'de_factor_table' and 'hde_factor_table' to properly handle DE[1-2], VCE and VDE clocks. * Add a common div table 'std12rate_div_table' for BISP and SENSOR[0-1] clocks converted to OWL_COMP_DIV. * Drop the now unused 'bisp_factor_table[]'. Additionally, drop the CLK_IGNORE_UNUSED flag for SENSOR[0-1] since there is no reason to always keep ON those clocks. Fixes: ed6b4795ece4 ("clk: actions: Add clock driver for S500 SoC") Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@gmail.com> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> Link: https://lore.kernel.org/r/e675820a46cd9930d8d576c6cae61d41c1a8416f.1623354574.git.cristian.ciocaltea@gmail.com Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-14clk: actions: Fix SD clocks factor table on Owl S500 SoCCristian Ciocaltea1-4/+2
[ Upstream commit fe1f71e338d77814da3ef44e9f64d32981a6ccdf ] Drop the unsupported entries in the factor table used for the SD[0-2] clocks definitions on the Actions Semi Owl S500 SoC. Fixes: ed6b4795ece4 ("clk: actions: Add clock driver for S500 SoC") Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@gmail.com> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> Link: https://lore.kernel.org/r/196c948d708a22b8198c95f064a0f6b6820f9980.1623354574.git.cristian.ciocaltea@gmail.com Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-14clk: actions: Fix UART clock dividers on Owl S500 SoCCristian Ciocaltea1-6/+6
[ Upstream commit 2dca2a619a907579e3e65e7c1789230c2b912e88 ] Use correct divider registers for the Actions Semi Owl S500 SoC's UART clocks. Fixes: ed6b4795ece4 ("clk: actions: Add clock driver for S500 SoC") Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@gmail.com> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> Link: https://lore.kernel.org/r/4714d05982b19ac5fec2ed74f54be42d8238e392.1623354574.git.cristian.ciocaltea@gmail.com Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-14clk: imx8mq: remove SYS PLL 1/2 clock gatesLucas Stach1-38/+18
[ Upstream commit c586f53ae159c6c1390f093a1ec94baef2df9f3a ] Remove the PLL clock gates as the allowing to gate the sys1_pll_266m breaks the uSDHC module which is sporadically unable to enumerate devices after this change. Also it makes AMP clock management harder with no obvious benefit to Linux, so just revert the change. Link: https://lore.kernel.org/r/20210528180135.1640876-1-l.stach@pengutronix.de Fixes: b04383b6a558 ("clk: imx8mq: Define gates for pll1/2 fixed dividers") Signed-off-by: Lucas Stach <l.stach@pengutronix.de> Reviewed-by: Abel Vesa <abel.vesa@nxp.com> Signed-off-by: Abel Vesa <abel.vesa@nxp.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-14clk: vc5: fix output disabling when enabling a FODLuca Ceresoli1-3/+24
[ Upstream commit fc336ae622df0ec114dbe5551a4d2760c535ecd0 ] On 5P49V6965, when an output is enabled we enable the corresponding FOD. When this happens for the first time, and specifically when writing register VC5_OUT_DIV_CONTROL in vc5_clk_out_prepare(), all other outputs are stopped for a short time and then restarted. According to Renesas support this is intended: "The reason for that is VC6E has synced up all output function". This behaviour can be disabled at least on VersaClock 6E devices, of which only the 5P49V6965 is currently implemented by this driver. This requires writing bit 7 (bypass_sync{1..4}) in register 0x20..0x50. Those registers are named "Unused Factory Reserved Register", and the bits are documented as "Skip VDDO<N> verification", which does not clearly explain the relation to FOD sync. However according to Renesas support as well as my testing setting this bit does prevent disabling of all clock outputs when enabling a FOD. See "VersaClock ® 6E Family Register Descriptions and Programming Guide" (August 30, 2018), Table 116 "Power Up VDD check", page 58: https://www.renesas.com/us/en/document/mau/versaclock-6e-family-register-descriptions-and-programming-guide Signed-off-by: Luca Ceresoli <luca@lucaceresoli.net> Reviewed-by: Adam Ford <aford173@gmail.com> Link: https://lore.kernel.org/r/20210527211647.1520720-1-luca@lucaceresoli.net Fixes: 2bda748e6ad8 ("clk: vc5: Add support for IDT VersaClock 5P49V6965") Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-14clk: tegra30: Use 300MHz for video decoder by defaultDmitry Osipenko1-1/+1
[ Upstream commit 56bb7c28ad00e7bcfc851c4e183c42d148d3ad4e ] The 600MHz is a too high clock rate for some SoC versions for the video decoder hardware and this may cause stability issues. Use 300MHz for the video decoder by default, which is supported by all hardware versions. Fixes: ed1a2459e20c ("clk: tegra: Add Tegra20/30 EMC clock implementation") Acked-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-14clk: meson: g12a: fix gp0 and hifi rangesJerome Brunet1-1/+1
[ Upstream commit bc794f8c56abddf709f1f84fcb2a3c9e7d9cc9b4 ] While some SoC samples are able to lock with a PLL factor of 55, others samples can't. ATM, a minimum of 60 appears to work on all the samples I have tried. Even with 60, it sometimes takes a long time for the PLL to eventually lock. The documentation says that the minimum rate of these PLLs DCO should be 3GHz, a factor of 125. Let's use that to be on the safe side. With factor range changed, the PLL seems to lock quickly (enough) so far. It is still unclear if the range was the only reason for the delay. Fixes: 085a4ea93d54 ("clk: meson: g12a: add peripheral clock controller") Signed-off-by: Jerome Brunet <jbrunet@baylibre.com> Acked-by: Neil Armstrong <narmstrong@baylibre.com> Link: https://lore.kernel.org/r/20210429090325.60970-1-jbrunet@baylibre.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-14clk: agilex/stratix10: fix bypass representationDinh Nguyen2-21/+91
commit 6855ee839699bdabb4b16cf942557fd763bcb1fa upstream. Each of these clocks(s2f_usr0/1, sdmmc_clk, gpio_db, emac_ptp, emac0/1/2) have a bypass setting that can use the boot_clk. The previous representation was not correct. Fix the representation. Fixes: 80c6b7a0894f ("clk: socfpga: agilex: add clock driver for the Agilex platform") Cc: stable@vger.kernel.org Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> Link: https://lore.kernel.org/r/20210611025201.118799-2-dinguyen@kernel.org Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-14clk: agilex/stratix10: remove noc_clkDinh Nguyen2-34/+30
commit efbe21df3e889c0f4bf682c2b7e2465d60b0127c upstream. Early documentation had a noc_clk, but in reality, it's just the noc_free_clk. Remove the noc_clk clock and just use the noc_free_clk. Fixes: 80c6b7a0894f ("clk: socfpga: agilex: add clock driver for the Agilex platform") Cc: stable@vger.kernel.org Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> Link: https://lore.kernel.org/r/20210611025201.118799-1-dinguyen@kernel.org Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-14clk: agilex/stratix10/n5x: fix how the bypass_reg is handledDinh Nguyen1-3/+8
commit dfd1427c3769ba51297777dbb296f1802d72dbf6 upstream. If the bypass_reg is set, then we can return the bypass parent, however, if there is not a bypass_reg, we need to figure what the correct parent mux is. The previous code never handled the parent mux if there was a bypass_reg. Fixes: 80c6b7a0894f ("clk: socfpga: agilex: add clock driver for the Agilex platform") Cc: stable@vger.kernel.org Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> Link: https://lore.kernel.org/r/20210611025201.118799-4-dinguyen@kernel.org Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-19clk: exynos7: Mark aclk_fsys1_200 as criticalPaweł Chmiel1-1/+6
commit 34138a59b92c1a30649a18ec442d2e61f3bc34dd upstream. This clock must be always enabled to allow access to any registers in fsys1 CMU. Until proper solution based on runtime PM is applied (similar to what was done for Exynos5433), mark that clock as critical so it won't be disabled. It was observed on Samsung Galaxy S6 device (based on Exynos7420), where UFS module is probed before pmic used to power that device. In this case defer probe was happening and that clock was disabled by UFS driver, causing whole boot to hang on next CMU access. Fixes: 753195a749a6 ("clk: samsung: exynos7: Correct CMU_FSYS1 clocks names") Signed-off-by: Paweł Chmiel <pawel.mikolaj.chmiel@gmail.com> Acked-by: Krzysztof Kozlowski <krzk@kernel.org> Link: https://lore.kernel.org/linux-clk/20201024154346.9589-1-pawel.mikolaj.chmiel@gmail.com [s.nawrocki: Added comment in the code] Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-14clk: uniphier: Fix potential infinite loopColin Ian King1-2/+2
[ Upstream commit f6b1340dc751a6caa2a0567b667d0f4f4172cd58 ] The for-loop iterates with a u8 loop counter i and compares this with the loop upper limit of num_parents that is an int type. There is a potential infinite loop if num_parents is larger than the u8 loop counter. Fix this by making the loop counter the same type as num_parents. Also make num_parents an unsigned int to match the return type of the call to clk_hw_get_num_parents. Addresses-Coverity: ("Infinite loop") Fixes: 734d82f4a678 ("clk: uniphier: add core support code for UniPhier clock driver") Signed-off-by: Colin Ian King <colin.king@canonical.com> Reviewed-by: Masahiro Yamada <masahiroy@kernel.org> Link: https://lore.kernel.org/r/20210409090104.629722-1-colin.king@canonical.com Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14clk: qcom: apss-ipq-pll: Add missing MODULE_DEVICE_TABLEChen Hui1-0/+1
[ Upstream commit d0a859edda46b45baeab9687d173102300d76e2b ] CONFIG_IPQ_APSS_PLL is tristate option and therefore this driver can be compiled as a module. This patch adds missing MODULE_DEVICE_TABLE definition which generates correct modalias for automatic loading of this driver when it is built as an external module. Fixes: ecd2bacfbbc4 ("clk: qcom: Add ipq apss pll driver") Signed-off-by: Chen Hui <clare.chenhui@huawei.com> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> Link: https://lore.kernel.org/r/20210409082352.233810-4-clare.chenhui@huawei.com Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14clk: qcom: a53-pll: Add missing MODULE_DEVICE_TABLEChen Hui1-0/+1
[ Upstream commit 790b516ada10a4dcc0f0a56dc0ced475d86d5820 ] CONFIG_QCOM_A53PLL is tristate option and therefore this driver can be compiled as a module. This patch adds missing MODULE_DEVICE_TABLE definition which generates correct modalias for automatic loading of this driver when it is built as an external module. Fixes: 0c6ab1b8f894 ("clk: qcom: Add A53 PLL support") Signed-off-by: Chen Hui <clare.chenhui@huawei.com> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> Link: https://lore.kernel.org/r/20210409082352.233810-3-clare.chenhui@huawei.com Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14clk: zynqmp: pll: add set_pll_mode to check condition in zynqmp_pll_enableQuanyang Wang1-1/+11
[ Upstream commit 394cdb69a3c30b33524cf1204afe5cceaba69cdc ] If there is a IOCTL_SET_PLL_FRAC_MODE request sent to ATF ever, we shouldn't skip invoking PM_CLOCK_ENABLE fn even though this pll has been enabled. In ATF implementation, it will only assign the mode to the variable (struct pm_pll *)pll->mode when handling IOCTL_SET_PLL_FRAC_MODE call. Invoking PM_CLOCK_ENABLE can force ATF send request to PWU to set the pll mode to PLL's register. There is a scenario that happens in enabling VPLL_INT(clk_id:96): 1) VPLL_INT has been enabled during booting. 2) A driver calls clk_set_rate and according to the rate, the VPLL_INT should be set to FRAC mode. Then zynqmp_pll_set_mode is called to pass IOCTL_SET_PLL_FRAC_MODE to ATF. Note that at this point ATF just stores the mode to a variable. 3) This driver calls clk_prepare_enable and zynqmp_pll_enable is called to try to enable VPLL_INT pll. Because of 1), the function zynqmp_pll_enable just returns without doing anything after checking that this pll has been enabled. In the scenario above, the pll mode of VPLL_INT will never be set successfully. So adding set_pll_mode to check condition to fix it. Fixes: 3fde0e16d016 ("drivers: clk: Add ZynqMP clock driver") Signed-off-by: Quanyang Wang <quanyang.wang@windriver.com> Tested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Link: https://lore.kernel.org/r/20210406153131.601701-1-quanyang.wang@windriver.com Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14clk: zynqmp: move zynqmp_pll_set_mode out of round_rate callbackQuanyang Wang1-6/+6
[ Upstream commit d7fd3f9f53df8bb2212dff70f66f12cae0e1a653 ] The round_rate callback should only perform rate calculation and not involve calling zynqmp_pll_set_mode to change the pll mode. So let's move zynqmp_pll_set_mode out of round_rate and to set_rate callback. Fixes: 3fde0e16d016 ("drivers: clk: Add ZynqMP clock driver") Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Quanyang Wang <quanyang.wang@windriver.com> Link: https://lore.kernel.org/r/20210406154015.602779-1-quanyang.wang@windriver.com Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14clk: imx: Fix reparenting of UARTs not associated with stdoutAdam Ford16-252/+54
[ Upstream commit 379c9a24cc239000b1dec53db02fe17a86947423 ] Most if not all i.MX SoC's call a function which enables all UARTS. This is a problem for users who need to re-parent the clock source, because any attempt to change the parent results in an busy error due to the fact that the clocks have been enabled already. clk: failed to reparent uart1 to sys_pll1_80m: -16 Instead of pre-initializing all UARTS, scan the device tree to see which UART clocks are associated to stdout, and only enable those UART clocks if it's needed early. This will move initialization of the remaining clocks until after the parenting of the clocks. When the clocks are shutdown, this mechanism will also disable any clocks that were pre-initialized. Fixes: 9461f7b33d11c ("clk: fix CLK_SET_RATE_GATE with clock rate protection") Suggested-by: Aisheng Dong <aisheng.dong@nxp.com> Signed-off-by: Adam Ford <aford173@gmail.com> Reviewed-by: Abel Vesa <abel.vesa@nxp.com> Tested-by: Ahmad Fatoum <a.fatoum@pengutronix.de> Signed-off-by: Abel Vesa <abel.vesa@nxp.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14media: aspeed: fix clock handling logicJae Hyun Yoo1-2/+2
[ Upstream commit 3536169f8531c2c5b153921dc7d1ac9fd570cda7 ] Video engine uses eclk and vclk for its clock sources and its reset control is coupled with eclk so the current clock enabling sequence works like below. Enable eclk De-assert Video Engine reset 10ms delay Enable vclk It introduces improper reset on the Video Engine hardware and eventually the hardware generates unexpected DMA memory transfers that can corrupt memory region in random and sporadic patterns. This issue is observed very rarely on some specific AST2500 SoCs but it causes a critical kernel panic with making a various shape of signature so it's extremely hard to debug. Moreover, the issue is observed even when the video engine is not actively used because udevd turns on the video engine hardware for a short time to make a query in every boot. To fix this issue, this commit changes the clock handling logic to make the reset de-assertion triggered after enabling both eclk and vclk. Also, it adds clk_unprepare call for a case when probe fails. clk: ast2600: fix reset settings for eclk and vclk Video engine reset setting should be coupled with eclk to match it with the setting for previous Aspeed SoCs which is defined in clk-aspeed.c since all Aspeed SoCs are sharing a single video engine driver. Also, reset bit 6 is defined as 'Video Engine' reset in datasheet so it should be de-asserted when eclk is enabled. This commit fixes the setting. Fixes: d2b4387f3bdf ("media: platform: Add Aspeed Video Engine driver") Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com> Reviewed-by: Joel Stanley <joel@jms.id.au> Reviewed-by: Eddie James <eajames@linux.ibm.com> Fixes: d3d04f6c330a ("clk: Add support for AST2600 SoC") Reviewed-by: Joel Stanley <joel@jms.id.au> Acked-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14clk: mvebu: armada-37xx-periph: Fix workaround for switching from L1 to L0Pali Rohár1-6/+39
[ Upstream commit e93033aff684641f71a436ca7a9d2a742126baaf ] When CPU frequency is at 250 MHz and set_rate() is called with 500 MHz (L1) quickly followed by a call with 1 GHz (L0), the CPU does not necessarily stay in L1 for at least 20ms as is required by Marvell errata. This situation happens frequently with the ondemand cpufreq governor and can be also reproduced with userspace governor. In most cases it causes CPU to crash. This change fixes the above issue and ensures that the CPU always stays in L1 for at least 20ms when switching from any state to L0. Signed-off-by: Marek Behún