summaryrefslogtreecommitdiffstats
path: root/drivers/clk/clk.c
Commit message (Collapse)AuthorAgeFilesLines
* clk: core: Force setting the phase delay when no changeJean-Francois Moine2016-08-301-5/+0
| | | | | | | | | | | | | | | This patch reverts commit 023bd7166be0 ("clk: skip unnecessary set_phase if nothing to do"), fixing two problems: * in some SoCs, the hardware phase delay depends on the rate ratio of the clock and its parent. So, changing this ratio may imply to set new hardware values, even if the logical delay is the same. * when the delay was the same as previously, an error was returned. Signed-off-by: Jean-Francois Moine <moinejf@free.fr> Fixes: 023bd7166be0 ("clk: skip unnecessary set_phase if nothing to do") Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: Simplify __of_clk_get_hw_from_provider()Stephen Boyd2016-08-261-11/+6
| | | | | | | | | | | | | | | | __of_clk_get_hw_from_provider() is confusing because it will return EPROBE_DEFER if there isn't a ->get() or ->get_hw() function pointer in a provider. That's just a bug though, and we used to NULL pointer exception when ->get() was missing anyway, so let's make this more obvious that they're not optional. The assumption is that most providers will implement ->get_hw() so we only fallback to the ->get() function if necessary. This clarifies the intent and removes any possibility of probe defer happening if clk providers are buggy. Reported-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: Return errors from clk providers in __of_clk_get_from_provider()Stephen Boyd2016-08-151-4/+5
| | | | | | | | | | | | | | | | | | | | Before commit 0861e5b8cf80 (clk: Add clk_hw OF clk providers, 2016-02-05) __of_clk_get_from_provider() would return an error pointer of the provider's choosing if there was a provider registered and EPROBE_DEFER otherwise. After that commit, it would return EPROBE_DEFER regardless of whether or not the provider returned an error. This is odd and can lead to behavior where clk consumers keep probe deferring when they should be seeing some other error. Let's restore the previous behavior where we only return EPROBE_DEFER when there isn't a provider in our of_clk_providers list. Otherwise, return the error from the last provider we find that matches the node. Reported-by: Masahiro Yamada <yamada.masahiro@socionext.com> Fixes: 0861e5b8cf80 ("clk: Add clk_hw OF clk providers") Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: use ERR_CAST() for __clk_create_clk()Masahiro Yamada2016-08-121-1/+1
| | | | | | | | This code is clear enough, but the intention will be even clearer with this. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: core: Avoid double initialization of clocksRicardo Ribalda Delgado2016-08-121-0/+4
| | | | | | | | | | Some clock providers can be initialized via of_clk_init() and also via platform device probe. Avoid double initialization of them by setting the OF_POPULATED flag. Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: migrate ref counts when orphans are reunitedMichael Turquette2016-08-111-2/+10
| | | | | | | | | | | | | | | | | | | It's always nice to see families reunited, and this is equally true when talking about parent clocks and their children. However, if the orphan clk had a positive prepare_count or enable_count, then we would not migrate those counts up the parent chain correctly. This has manifested with the recent critical clocks feature, which often enables clocks very early, before their parents have been registered. Fixed by replacing the call to clk_core_reparent with calls to __clk_set_parent_{before,after}. Cc: James Liao <jamesjj.liao@mediatek.com> Cc: Erin Lo <erin.lo@mediatek.com> Signed-off-by: Michael Turquette <mturquette@baylibre.com> [sboyd@codeaurora.org: Recalc accuracies and rates too] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: core: support clocks which requires parents enable (part 2)Dong Aisheng2016-07-011-15/+33
| | | | | | | | | | | | | | | | | | | | | On Freescale i.MX7D platform, all clocks operations, including enable/disable, rate change and re-parent, requires its parent clock on. Current clock core can not support it well. This patch adding flag CLK_OPS_PARENT_ENABLE to handle this special case in clock core that enable its parent clock firstly for each operation and disable it later after operation complete. The patch part 2 fixes set clock rate and set parent while its parent is off. The most special case is for set_parent() operation which requires all parents including both old and new one to be enabled at the same time during the operation. Cc: Michael Turquette <mturquette@baylibre.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Shawn Guo <shawnguo@kernel.org> Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com> [sboyd@codeaurora.org: Move set_rate tracepoint after prepare_enable] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: core: support clocks which requires parents enable (part 1)Dong Aisheng2016-07-011-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On Freescale i.MX7D platform, all clocks operations, including enable/disable, rate change and re-parent, requires its parent clock enable. Current clock core can not support it well. This patch introduce a new flag CLK_OPS_PARENT_ENABLE to handle this special case in clock core that enable its parent clock firstly for each operation and disable it later after operation complete. The patch part 1 fixes the possible disabling clocks while its parent is off during kernel booting phase in clk_disable_unused_subtree(). Before the completion of kernel booting, clock tree is still not built completely, there may be a case that the child clock is on but its parent is off which could be caused by either HW initial reset state or bootloader initialization. Taking bootloader as an example, we may enable all clocks in HW by default. And during kernel booting time, the parent clock could be disabled in its driver probe due to calling clk_prepare_enable and clk_disable_unprepare. Because it's child clock is only enabled in HW while its SW usecount in clock tree is still 0, so clk_disable of parent clock will gate the parent clock in both HW and SW usecount ultimately. Then there will be a child clock is still on in HW but its parent is already off. Later in clk_disable_unused(), this clock disable accessing while its parent off will cause system hang due to the limitation of HW which must require its parent on. This patch simply enables the parent clock first before disabling if flag CLK_OPS_PARENT_ENABLE is set in clk_disable_unused_subtree(). This is a simple solution and only affects booting time. After kernel booting up the clock tree is already created, there will be no case that child is off but its parent is off. So no need do this checking for normal clk_disable() later. Cc: Michael Turquette <mturquette@baylibre.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Shawn Guo <shawnguo@kernel.org> Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: move clk_disable_unused after clk_core_disable_unprepare functionDong Aisheng2016-07-011-98/+98
| | | | | | | | | | | | | | No function level change, just moving code place. clk_disable_unused function will need to call clk_core_prepare_enable/ clk_core_disable_unprepare when adding CLK_OPS_PARENT_ENABLE features. So move it after clk_core_disable_unprepare to avoid adding forward declared functions later. Cc: Michael Turquette <mturquette@baylibre.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Shawn Guo <shawnguo@kernel.org> Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: introduce clk_core_enable_lock and clk_core_disable_lock functionsDong Aisheng2016-07-011-22/+63
| | | | | | | | | | | | | | | | | | | This can be useful when clock core wants to enable/disable clocks. Then we don't have to convert the struct clk_core to struct clk to call clk_enable/clk_disable which is a bit un-align with exist using. And after introduce clk_core_{enable|disable}_lock, we can refine clk_enable and clk_disable a bit. As well as clk_core_{enable|disable}_lock, we also added clk_core_{prepare|unprepare}_lock and clk_core_prepare_enable/ clk_core_unprepare_disable for clock core to easily use. Cc: Michael Turquette <mturquette@baylibre.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Shawn Guo <shawnguo@kernel.org> Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: correct comments for __clk_determine_ratePeng Fan2016-06-201-3/+1
| | | | | | | | | Correct comments for __clk_determine_rate. Signed-off-by: Peng Fan <van.freenix@gmail.com> Cc: Michael Turquette <mturquette@baylibre.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: Remove unused variableLee Jones2016-06-201-2/+1
| | | | | Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* Merge commit 'f17a0dd1c2e0' into clk-nextMichael Turquette2016-06-161-4/+4
|\
| * clk: Use _rcuidle suffix to allow clk_core_enable() to used from idlePaul E. McKenney2016-06-151-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This commit fixes the RCU use-from-idle bug corresponding the following splat: > [ INFO: suspicious RCU usage. ] > 4.6.0-rc5-next-20160426+ #1127 Not tainted > ------------------------------- > include/trace/events/clk.h:45 suspicious rcu_dereference_check() usage! > > other info that might help us debug this: > > > RCU used illegally from idle CPU! > rcu_scheduler_active = 1, debug_locks = 0 > RCU used illegally from extended quiescent state! > 2 locks held by swapper/0/0: > #0: (&oh->hwmod_key#30){......}, at: [<c0121afc>] omap_hwmod_enable+0x18/0x44 > #1: (enable_lock){......}, at: [<c0630684>] clk_enable_lock+0x18/0x124 > > stack backtrace: > CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1127 > Hardware name: Generic OMAP36xx (Flattened Device Tree) > [<c0110290>] (unwind_backtrace) from [<c010c3a8>] (show_stack+0x10/0x14) > [<c010c3a8>] (show_stack) from [<c047fd68>] (dump_stack+0xb0/0xe4) > [<c047fd68>] (dump_stack) from [<c06315c0>] (clk_core_enable+0x1e0/0x36c) > [<c06315c0>] (clk_core_enable) from [<c0632298>] (clk_enable+0x1c/0x38) > [<c0632298>] (clk_enable) from [<c01204e0>] (_enable_clocks+0x18/0x7c) > [<c01204e0>] (_enable_clocks) from [<c012137c>] (_enable+0x114/0x2ec) > [<c012137c>] (_enable) from [<c0121b08>] (omap_hwmod_enable+0x24/0x44) > [<c0121b08>] (omap_hwmod_enable) from [<c0122ad0>] (omap_device_enable+0x3c/0x90) > [<c0122ad0>] (omap_device_enable) from [<c0122b34>] (_od_runtime_resume+0x10/0x38) > [<c0122b34>] (_od_runtime_resume) from [<c052cc00>] (__rpm_callback+0x2c/0x60) > [<c052cc00>] (__rpm_callback) from [<c052cc54>] (rpm_callback+0x20/0x80) > [<c052cc54>] (rpm_callback) from [<c052df7c>] (rpm_resume+0x3d0/0x6f0) > [<c052df7c>] (rpm_resume) from [<c052e2e8>] (__pm_runtime_resume+0x4c/0x64) > [<c052e2e8>] (__pm_runtime_resume) from [<c04bf2c4>] (omap2_gpio_resume_after_idle+0x54/0x68) > [<c04bf2c4>] (omap2_gpio_resume_after_idle) from [<c01269dc>] (omap3_enter_idle_bm+0xfc/0x1ec) > [<c01269dc>] (omap3_enter_idle_bm) from [<c0601888>] (cpuidle_enter_state+0x80/0x3d4) > [<c0601888>] (cpuidle_enter_state) from [<c0183b08>] (cpu_startup_entry+0x198/0x3a0) > [<c0183b08>] (cpu_startup_entry) from [<c0b00c0c>] (start_kernel+0x354/0x3c8) > [<c0b00c0c>] (start_kernel) from [<8000807c>] (0x8000807c) Reported-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Tested-by: Tony Lindgren <tony@atomide.com> Tested-by: Guenter Roeck <linux@roeck-us.net> Cc: Russell King <linux@arm.linux.org.uk> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Michael Turquette <mturquette@baylibre.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: <linux-omap@vger.kernel.org> Cc: <linux-arm-kernel@lists.infradead.org> Cc: <linux-clk@vger.kernel.org>
| * clk: Add _rcuidle tracepoints to allow clk_core_disable() use from idlePaul E. McKenney2016-06-151-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This commit adds an _rcuidle suffix to a pair of trace events to prevent the following splat: > =============================== > [ INFO: suspicious RCU usage. ] > 4.6.0-rc5-next-20160426+ #1114 Not tainted > ------------------------------- > include/trace/events/clk.h:59 suspicious rcu_dereference_check() usage! > > other info that might help us debug this: > > > RCU used illegally from idle CPU! > rcu_scheduler_active = 1, debug_locks = 0 > RCU used illegally from extended quiescent state! > 2 locks held by swapper/0/0: > #0: (&oh->hwmod_key#30){......}, at: [<c0121b40>] omap_hwmod_idle+0x18/0x44 > #1: (enable_lock){......}, at: [<c0630998>] clk_enable_lock+0x18/0x124 > > stack backtrace: > CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1114 > Hardware name: Generic OMAP36xx (Flattened Device Tree) > [<c0110290>] (unwind_backtrace) from [<c010c3a8>] (show_stack+0x10/0x14) > [<c010c3a8>] (show_stack) from [<c047fd68>] (dump_stack+0xb0/0xe4) > [<c047fd68>] (dump_stack) from [<c0631618>] (clk_core_disable+0x17c/0x348) > [<c0631618>] (clk_core_disable) from [<c0632774>] (clk_disable+0x24/0x30) > [<c0632774>] (clk_disable) from [<c0120590>] (_disable_clocks+0x18/0x7c) > [<c0120590>] (_disable_clocks) from [<c0121680>] (_idle+0x12c/0x230) > [<c0121680>] (_idle) from [<c0121b4c>] (omap_hwmod_idle+0x24/0x44) > [<c0121b4c>] (omap_hwmod_idle) from [<c0122c24>] (omap_device_idle+0x3c/0x90) > [<c0122c24>] (omap_device_idle) from [<c052cc00>] (__rpm_callback+0x2c/0x60) > [<c052cc00>] (__rpm_callback) from [<c052cc54>] (rpm_callback+0x20/0x80) > [<c052cc54>] (rpm_callback) from [<c052d150>] (rpm_suspend+0x100/0x768) > [<c052d150>] (rpm_suspend) from [<c052ec58>] (__pm_runtime_suspend+0x64/0x84) > [<c052ec58>] (__pm_runtime_suspend) from [<c04bf25c>] (omap2_gpio_prepare_for_idle+0x5c/0x70) > [<c04bf25c>] (omap2_gpio_prepare_for_idle) from [<c0125568>] (omap_sram_idle+0x140/0x244) > [<c0125568>] (omap_sram_idle) from [<c01269dc>] (omap3_enter_idle_bm+0xfc/0x1ec) > [<c01269dc>] (omap3_enter_idle_bm) from [<c0601bdc>] (cpuidle_enter_state+0x80/0x3d4) > [<c0601bdc>] (cpuidle_enter_state) from [<c0183b08>] (cpu_startup_entry+0x198/0x3a0) > [<c0183b08>] (cpu_startup_entry) from [<c0b00c0c>] (start_kernel+0x354/0x3c8) > [<c0b00c0c>] (start_kernel) from [<8000807c>] (0x8000807c) Reported-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Tested-by: Tony Lindgren <tony@atomide.com> Tested-by: Guenter Roeck <linux@roeck-us.net> Cc: Russell King <linux@arm.linux.org.uk> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Michael Turquette <mturquette@baylibre.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: <linux-omap@vger.kernel.org> Cc: <linux-arm-kernel@lists.infradead.org> Cc: <linux-clk@vger.kernel.org>
* | clk: fix critical clock lockingMaxime Ripard2016-05-191-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The critical clock handling in __clk_core_init isn't taking the enable lock before calling clk_core_enable, which in turns triggers the warning in the lockdep_assert_held call in that function when lockep is enabled. Add the calls to clk_enable_lock/unlock to make sure it doesn't happen. Fixes: 32b9b1096186 ("clk: Allow clocks to be marked as CRITICAL") Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Reviewed-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* | clk: fix comment of devm_clk_hw_register()Masahiro Yamada2016-05-021-1/+1
| | | | | | | | | | | | | | | | | | Unlike devm_clk_register(), devm_clk_hw_register() returns integer. So, the statement "Clocks returned from this function ..." sounds odd. Adjust the comment for this new API. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* | Merge branch 'clk-hw-register' (early part) into clk-nextStephen Boyd2016-04-211-4/+167
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 'clk-hw-register' (early part): clk: fixed-rate: Add hw based registration APIs clk: gpio: Add hw based registration APIs clk: composite: Add hw based registration APIs clk: fractional-divider: Add hw based registration APIs clk: fixed-factor: Add hw based registration APIs clk: mux: Add hw based registration APIs clk: gate: Add hw based registration APIs clk: divider: Add hw based registration APIs clkdev: Add clk_hw based registration APIs clk: Add clk_hw OF clk providers clk: Add {devm_}clk_hw_{register,unregister}() APIs clkdev: Remove clk_register_clkdevs()
| * | clk: Add clk_hw OF clk providersStephen Boyd2016-04-191-4/+81
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that we have a clk registration API that doesn't return struct clks, we need to have some way to hand out struct clks via the clk_get() APIs that doesn't involve associating struct clk pointers with an OF node. Currently we ask the OF provider to give us a struct clk pointer for some clkspec, turn that struct clk into a struct clk_hw and then allocate a new struct clk to return to the caller. Let's add a clk_hw based OF provider hook that returns a struct clk_hw directly, so that we skip the intermediate step of converting from struct clk to struct clk_hw. Eventually when we've converted all OF clk providers to struct clk_hw based APIs we can remove the struct clk based ones. It should also be noted that we change the onecell provider to have a flex array instead of a pointer for the array of clk_hw pointers. This allows providers to allocate one structure of the correct length in one step instead of two. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
| * | clk: Add {devm_}clk_hw_{register,unregister}() APIsStephen Boyd2016-04-191-0/+86
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We've largely split the clk consumer and provider APIs along struct clk and struct clk_hw, but clk_register() still returns a struct clk pointer for each struct clk_hw that's registered. Eventually we'd like to only allocate struct clks when there's a user, because struct clk is per-user now, so clk_register() needs to change. Let's add new APIs to register struct clk_hws, but this time we'll hide the struct clk from the caller by returning an int error code. Also add an unregistration API that takes the clk_hw structure that was passed to the registration API. This way provider drivers never have to deal with a struct clk pointer unless they're using the clk consumer APIs. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* | clk: Provide OF helper to mark clocks as CRITICALLee Jones2016-04-091-0/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This call matches clocks which have been marked as critical in DT and sets the appropriate flag. These flags can then be used to mark the clock core flags appropriately prior to registration. Legacy bindings requiring this feature must add the clock-critical property to their binding descriptions, as it is not a part of common-clock binding. Cc: devicetree@vger.kernel.org Signed-off-by: Lee Jones <lee.jones@linaro.org> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Michael Turquette <mturquette@baylibre.com> Link: lkml.kernel.org/r/1455225554-13267-4-git-send-email-mturquette@baylibre.com
* | clk: WARN_ON about to disable a critical clockLee Jones2016-04-091-0/+6
| | | | | | | | | | | | | | Signed-off-by: Lee Jones <lee.jones@linaro.org> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Michael Turquette <mturquette@baylibre.com> Link: lkml.kernel.org/r/1455225554-13267-3-git-send-email-mturquette@baylibre.com
* | clk: Allow clocks to be marked as CRITICALLee Jones2016-04-091-0/+5
|/ | | | | | | | | | | Critical clocks are those which must not be gated, else undefined or catastrophic failure would occur. Here we have chosen to ensure the prepare/enable counts are correctly incremented, so as not to confuse users with enabled clocks with no visible users. Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Michael Turquette <mturquette@baylibre.com> Link: lkml.kernel.org/r/1455225554-13267-2-git-send-email-mturquette@baylibre.com
* clk: Make of_clk_get_parent_count() return unsigned intsStephen Boyd2016-02-261-2/+14
| | | | | | | | | | | | | | | | | | Russell King recently pointed out a bug in the clk-gpio code where it fails to register the clk if of_clk_get_parent_count() returns an error because the "clocks" property isn't present in the DT node. If we're trying to count parents from DT we'd like to know the count, not if there is a "clocks" property or not. Furthermore, some drivers are assigning the return value to their clk_init_data::num_parents member which is unsigned, leading to potentially large numbers of parents when the property isn't present. Let's change the API to return an unsigned int instead of an int. All the callers just want to know the count anyway, and this avoids the bug that was in the clk-gpio driver. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: Ignore disabled DT clock providersGeert Uytterhoeven2016-02-261-0/+3
| | | | | | | | | | | | | | | | | | of_clk_init() uses for_each_matching_node_and_match() to find clock providers, which returns all matching device nodes, whether they are enabled or not. Hence clock providers that are disabled explicitly in DT using e.g. "status = "disabled"; are still activated. Add a check to ignore device nodes that are not enabled, like of_irq_init() does. Reported-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: skip unnecessary set_phase if nothing to doShawn Lin2016-02-251-0/+5
| | | | | | | | | | Let's compare the degrees from clk_set_rate with clk->core->phase. If the requested degrees is already there, skip the following steps. Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> [sboyd@codeaurora.org: s/drgrees/degrees/ in commit text] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: Update some outdated commentsStephen Boyd2016-02-221-3/+3
| | | | | | | | __clk_init() was renamed to __clk_core_init() but these comments weren't updated. Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* Revert "clk: avoid circular clock topology"Stephen Boyd2016-02-221-40/+0
| | | | | | | | | | | | | | | | | | | | | | This reverts commit 858d5881564026cbc4e6f5e25ae878a27df5d4c9. Joachim reports that this commit breaks lpc18xx boot. This is because the hardware has circular clk topology where PLLs can feed into dividers and the same dividers can feed into the PLLs. The hardware is designed this way so that you can choose to put the divider before the PLL or after the PLL depending on what you configure to be the parent of the divider and what you configure to be the parent of the PLL. So let's drop this patch for now because we have hardware that actually has loops. A future patch could check for circular parents when we change parents and fail the switch, but that's probably best left to some debugging Kconfig option so that we don't suffer the sanity checking cost all the time. Reported-by: Joachim Eastwood <manabian@gmail.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: Make of_clk_get_from_provider() available to modulesAndrew F. Davis2016-02-171-0/+1
| | | | | | | | Export symbol of_clk_get_from_provider so it can be used in loadable kernel modules Signed-off-by: Andrew F. Davis <afd@ti.com> Signed-off-by: Michael Turquette <mturquette@baylibre.com>
* clk: fix __clk_init_parent() for single parent clocksMasahiro Yamada2016-02-091-1/+1
| | | | | | | | | | | | | | | | | | | Before commit b3d192d5121f ("clk: simplify __clk_init_parent()"), __clk_init_parent() called .get_parent() only for multi-parent clocks. That commit changed the behavior to call .get_parent() if available even for single-parent clocks and root clocks. It turned out a problem because there are some single-parent clocks that implement .get_parent() callback and return non-zero index. The SOCFPGA clock is the case; the commit broke the SOCFPGA boards. To keep the original behavior, invoke .get_parent() only when num_parents is greater than 1. Fixes: b3d192d5121f ("clk: simplify __clk_init_parent()") Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reported-by: Dinh Nguyen <dinguyen@opensource.altera.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: Deprecate CLK_IS_ROOTStephen Boyd2016-02-061-3/+3
| | | | | | | | | | | We don't use CLK_IS_ROOT but in a few places in the common clk framework core. Let's replace those checks with a check for the number of parents a clk has instead of the flag, freeing up one flag for something else. We don't remove the flag yet so that things keep building, but we'll remove it once all drivers have removed their flag usage. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: unlock for handling unregistered clockInsu Yun2016-02-021-2/+2
| | | | | | | | | If clock is already unregistered, it returns with holding lock. It needs to be unlocked. Signed-off-by: Insu Yun <wuninsu@gmail.com> [sboyd@codeaurora.org: Use goto instead] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: slightly optimize clk_core_set_parent()Masahiro Yamada2016-02-021-1/+1
| | | | | | | | | If clk_fetch_parent_index() fails, p_rate is unused. Move the assignment after the error checking. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: simplify clk_fetch_parent_index() functionMasahiro Yamada2016-02-021-16/+2
| | | | | | | | | The clk_core_get_parent_by_index can be used as a helper function to simplify the implementation of clk_fetch_parent_index(). Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: make sure parent is not NULL in clk_fetch_parent_index()Masahiro Yamada2016-02-021-0/+3
| | | | | | | | | | | | If parent is given with NULL, clk_fetch_parent_index() could return a positive index value. Currently, parent is checked by the callers of this function, but it would be safer to do it in this function. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: walk the orphan clock list more simplyMasahiro Yamada2016-02-021-15/+6
| | | | | | | | | This loop can be much simpler. If a new parent is available for orphan clocks, __clk_init_parent(orphan) can detect it. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: avoid circular clock topologyMasahiro Yamada2016-02-021-0/+40
| | | | | | | | | | | | | | | | | | | | | | | | Currently, clk_register() never checks a circular parent looping, but clock providers could register such an insane clock topology. For example, "clk_a" could have "clk_b" as a parent, and vice versa. In this case, clk_core_reparent() creates a circular parent list and __clk_recalc_accuracies() calls itself recursively forever. The core infrastructure should be kind enough to bail out, showing an appropriate error message in such a case. This helps to easily find a bug in clock providers. (uh, I made such a silly mistake when I was implementing my clock providers first. I was upset because the kernel did not respond, without any error message.) This commit adds a new helper function, __clk_is_ancestor(). It returns true if the second argument is a possible ancestor of the first one. If a clock core is a possible ancestor of itself, it would make a loop when it were registered. That should be detected as an error. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: simplify __clk_init_parent()Masahiro Yamada2016-02-021-34/+4
| | | | | | | | | | | | | The translation from the index into clk_core is done by clk_core_get_parent_by_index(). The if-block for num_parents == 1 case is duplicating the code in the clk_core_get_parent_by_index(). Drop the "if (num_parents == 1)" from the special case. Instead, set the index to zero if .get_parent() is missing. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: move checking .get_parent to __clk_core_init()Masahiro Yamada2016-02-021-7/+7
| | | | | | | | | | | The .get_parent is mandatory for multi-parent clocks. Move the check to __clk_core_init(), like other callback checkings. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Vladimir Zapolskiy <vz@mleia.com> [sboyd@codeaurora.org: Squashed in error path handling, fix typos in commit message] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: replace pr_warn() with pr_err() for fatal casesMasahiro Yamada2016-02-011-5/+5
| | | | | | | | | These three cases let clk_register() fail. They should be considered as error messages. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: drop the initial core->parents look-ups from __clk_core_init()Masahiro Yamada2016-02-011-11/+0
| | | | | | | | | The core->parents is a cache to save expensive clock parent look-ups. It will be filled as needed later. We do not have to do it here. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: simplify clk_core_get_parent_by_index()Masahiro Yamada2016-02-011-7/+6
| | | | | | | | | | | Drop the "if (!core->parents)" case and refactor the function a bit because core->parents is always allocated. (Strictly speaking, it is ZERO_SIZE_PTR if core->num_parents == 0, but such a case is omitted by the if-conditional above.) Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: move core->parents allocation to clk_register()Masahiro Yamada2016-02-011-32/+19
| | | | | | | | | | | | | | | | | | | | | | | | Currently, __clk_core_init() allows failure of the kcalloc() for the core->parents. So, clk_fetch_parent_index() and __clk_init_parent() also try to allocate core->parents in case it has not been allocated yet. Scattering memory allocation here and there makes things complicated. Like other clk_core members, allocate core->parents in clk_register() and let it fail in case of memory shortage. If we cannot allocate such a small piece of memory, the system is already insane. There is no point to postpone the memory allocation. Also, allocate core->parents regardless of core->num_parents. We want it even if core->num_parents == 1 because clk_fetch_parent_index() might be called against the clk_core with a single parent. If core->num_parents == 0, core->parents is set to ZERO_SIZE_PTR. It is harmless because no access happens to core->parents in such a case. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: change sizeof(struct clk *) to sizeof(*core->parents)Masahiro Yamada2016-02-011-4/+4
| | | | | | | | | | | | | | Now, the clock parent is not "struct clk *", but "struct clk_core *". Of course, the size of a pointer is always same, but strictly speaking, sizeof(struct clk *) should be sizeof(struct clk_core *) here. This mismatch happened when we split the structure into struct clk and struct clk_core. For the potential possibility of future renaming, sizeof(*core->parents) would be better. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: remove unnecessary !core->parents conditionalMasahiro Yamada2016-02-011-4/+1
| | | | | | | | | | | This if-block has been here since the introduction of the common clock framework. Now no clock drivers are statically initialized. core->parent is always NULL at this point. Drop the redundant check and the confusing comment. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: rename __clk_init() into __clk_core_init()Masahiro Yamada2016-02-011-3/+3
| | | | | | | | | Now this function takes clk_core as its argument. __clk_core_init() would be more suitable for the name of this function. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: change the argument of __clk_init() into pointer to clk_coreMasahiro Yamada2016-02-011-8/+5
| | | | | | | | | The argument clk_user is used only for the clk_user->core. The rest of this function only takes care of clk_core. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk: remove unused first argument of __clk_init()Masahiro Yamada2016-02-011-3/+2
| | | | | | | | The "struct device *dev" is not used at all in this function. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* Merge branch 'clk-rockchip' into clk-nextMichael Turquette2015-12-231-0/+18
|\
| * clk: add flag for clocks that need to be enabled on rate changesHeiko Stuebner2015-12-231-0/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | Some clocks need to be enabled to accept rate changes. This patch adds a new flag CLK_SET_RATE_UNGATE that lets clk_change_rate enable the clock before trying to change the rate and disable it again afterwards. This of course doesn't effect clocks that are already running at that point, as their refcount will only temporarily increase. Signed-off-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk> Reviewed-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk> Signed-off-by: Michael Turquette <mturquette@baylibre.com>
OpenPOWER on IntegriCloud