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path: root/arch/arm/mach-omap2/pm34xx.c
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2009-11-11OMAP3: PM: Added resched check into idle callsTero Kristo
Fixes a bug where scheduling is delayed until next wakeup due to race condition (e.g. interrupt requests scheduling just before omap_sram_idle is entered.) Signed-off-by: Tero Kristo <tero.kristo@nokia.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-11OMAP3: PM: idle: Remove fclk check for idle loopPeter 'p2' De Schrijver
This patch removes the check to see if some functional clocks are still enabled before entering sleep. This is no longer needed when using safe state (C1) that keeps CORE active. Signed-off-by: Peter 'p2' De Schrijver <peter.de-schrijver@nokia.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-11OMAP3: PM: Use pwrdm_set_next_pwrst instead of set_pwrdm_state in idle loopJouni Hogander
It is more efficient to use pwrdm_set_next_pwrst for mpu, core and neon instead of set_pwrdm_state in idle loop. It is anyway known that those are active in idle loop. So no need to use set_pwrdm_state. Signed-off-by: Jouni Hogander <jouni.hogander@nokia.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-11OMAP3: PM: CPUidle: fix init sequencingKalle Jokiniemi
Previously omap3_idle_init() was called in device_init, while omap_pm_init() is called at late_initcall. This causes the cpu idle driver to call omap_sram_idle before it is properly initialized. This patch fixes the issue by moving omap3_idle_init into omap3_pm_init. Signed-off-by: Kalle Jokiniemi <ext-kalle.jokiniemi@nokia.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-11OMAP3: PM: CPUidle: support retention and off-mode C-statesRajendra Nayak
This patch adds support and enables state C4(MPU RET + CORE RET) and MPU OFF states (C3 and C5.) Signed-off-by: Rajendra Nayak <rnayak@ti.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-11OMAP3: PM: CPUidle: base driver and support for C1-C2Rajendra Nayak
Basic CPUidle driver for OMAP3 with deepest sleep state supported being MPU CSWR. Signed-off-by: Rajendra Nayak <rnayak@ti.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-11OMAP3: PM: Program SDRC to send self refresh on timeout of AUTO_CNTRajendra Nayak
Due to an OMAP3 errata (1.142), on HS/EMU devices SDRC should be programed to issue automatic self refresh on timeout of AUTO_CNT = 1 prior to any transition to OFF mode. This is needed only on sil rev's ES3.0 and above. This patch enables the above needed WA in the SDRC power register value stored in scratchpad, so that ROM code restores this value in SDRC POWER on the wakeup path. The original SDRC POWER register value is stored and restored back in omap_sram_idle() function. This fixes some random crashes observed while stressing suspend on HS/EMU devices. Signed-off-by: Rajendra Nayak <rnayak@ti.com> Signed-off-by: Kalle Jokiniemi <kalle.jokiniemi@digia.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-11OMAP3: PM: Enable IO-CHAIN wakeupKalle Jokiniemi
OMAP 3430 ES3.1 chips have a separate bit for IO daisy-chain wake up enabling. It needs to be enabled when entering retention or off state, otherwise waking up might not work in all situations. Signed-off-by: Kalle Jokiniemi <kalle.jokiniemi@digia.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-11OMAP3: PM: MPU and CORE should stay awake if there is CAM domain ACTIVETero Kristo
MPU and CORE should stay awake if there is CAM domain ACTIVE. This is because that module doesn't have wake-up capability. This should replace the patch that is currently in the PM branch. Signed-off-by: Jouni Hogander <jouni.hogander@nokia.com> Signed-off-by: Tero Kristo <tero.kristo@nokia.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-11OMAP3: PM: Prevent PER from going OFF when CORE is going INATero Kristo
OMAP3 can't generate wakeups in this state, thus it is not permitted. Signed-off-by: Tero Kristo <tero.kristo@nokia.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-11OMAP3: PM: decouple PER and CORE context save and restoreKevin Hilman
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-11PM debug: allow configurable wakeup from suspend on OMAP GPtimerKevin Hilman
Using debugfs, export a configurable wakeup timer to be used to wakeup system from suspend. If a non-zero value is written to /debug/pm_debug/wakeup_timer_seconds, A timer wakeup event will wake the system and resume after the configured number of seconds. Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-11OMAP3: PM debug: allow runtime toggle of PM featuresKevin Hilman
Allow enable/disable of low-power states during idle. To enable low-power idle: echo 1 > /debug/pm_debug/sleep_while_idle to disable: echo 0 > /debug/pm_debug/sleep_while_idle Also allow enable/disable of OFF-mode. To enable: echo 1 > /debug/pm_debug/enable_off_mode to disable: echo 0 > /debug/pm_debug/enable_off_mode Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-11ARM: OMAP: SMS: save/restore of SMS_SYSCONFIG for off-modeKalle Jokiniemi
The SMS_SYSCONFIG register gets reset in off mode, added a save/restore mechanism for that. Signed-off-by: Kalle Jokiniemi <kalle.jokiniemi@digia.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-11OMAP3: PM: Fix secure SRAM context save/restoreKalle Jokiniemi
The secure sram context save uses dma channels 0 and 1. In order to avoid collision between kernel DMA transfers and ROM code dma transfers, we need to reserve DMA channels 0 1 on high security devices. A bug in ROM code leaves dma irq status bits uncleared. Hence those irq status bits need to be cleared when restoring DMA context after off mode. There was also a faulty parameter given to PPA in the secure ram context save assembly code, which caused interrupts to be enabled during secure ram context save. This caused the save to fail sometimes, which resulted the saved context to be corrupted, but also left DMA channels in secure mode. The secure mode DMA channels caused "DMA secure error with device 0" errors to be displayed. Signed-off-by: Kalle Jokiniemi <kalle.jokiniemi@digia.com> Signed-off-by: Jouni Hogander <jouni.hogander@nokia.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-11OMAP3: PM: Enable SDRAM auto-refresh during sleepTero Kristo
Fix for ES3.0 bug: SDRC not sending auto-refresh when OMAP wakes-up from OFF mode (warning for HS devices.) Signed-off-by: Tero Kristo <tero.kristo@nokia.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-11OMAP3: PM: save secure RAM only during initTero Kristo
The function omap3_save_secure_ram() is now called only once during the initialization of the device and consequent sleep cycles will re-use the same saved contents for secure RAM. Users who need secure services should do secure RAM saving before entering off-mode, if a secure service has been accessed after last save. There are both latency and reliability issues with saving secure RAM context in the idle path. The context save uses a hardware resource which takes an order of hundreds of milliseconds to initialize after a wake up from off-mode, and also there is no way of checking whether it is ready from kernel side or not. It just crashes if you use it too quickly Additional fix to ensure scratchpad save is done after secure RAM by Roger Quadros. Signed-off-by: Tero Kristo <tero.kristo@nokia.com> Signed-off-by: Roger Quadros <ext-roger.quadros@nokia.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-11OMAP3 PM: off-mode support for HS/EMU devicesTero Kristo
For HS/EMU devices, some additional resources need to be saved/restored for off-mode support. Namely, saving the secure RAM and a pointer to it in the scratchpad. Signed-off-by: Tero Kristo <tero.kristo@nokia.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-11OMAP: PM: DMA context save/restore for off-mode supportTero Kristo
For HS/EMU devices, these additional features are also used: - DMA interrupt disable routine added - Added DMA controller reset to DMA context restore Signed-off-by: Tero Kristo <tero.kristo@nokia.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-11OMAP3: PM: CORE domain off-mode supportRajendra Nayak
Add context save and restore for CORE powerdomain resources in order to support off-mode. Signed-off-by: Rajendra Nayak <rnayak@ti.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-11OMAP3: PM: MPU off-mode supportRajendra Nayak
Adds a 'save_state' option when calling into SRAM idle function and adds some minor cleanups of SRAM asm code. Signed-off-by: Rajendra Nayak <rnayak@ti.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-11OMAP3: PM: Restore MMU table entryRajendra Nayak
During the MMU restoration on the restore path from MPU OFF, the page table entry for the page consisting of the code being executed is modified to make MMU return VA=PA. The MMU is then enabled and the original entry is being stored in scratchpad. This patch reads the original values stored in scratchpad, and restores them back. Signed-off-by: Rajendra Nayak <rnayak@ti.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-11OMAP3: PM: handle PER/NEON/CORE in idleRajendra Nayak
Expand the powerdomains handled in the idle path to include PER, NEON and CORE. This includes properly clearing the previous powerstates, linking NEON state to MPU state and calling the UART prepare functions for only the appropraite powerdomain transitions (CORE for UART1,2, PER for UART3.) Signed-off-by: Rajendra Nayak <rnayak@ti.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-11OMAP3: PM: restore SRAM functions after off-mode.Rajendra Nayak
Generalize the copy of SRAM functions into omap_push_sram_idle() so it can be used on init but also after off-mode transitions. Signed-off-by: Rajendra Nayak <rnayak@ti.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-11-10Merge branch '7xx-iosplit-plat' with omap-fixesTony Lindgren
2009-10-22omap3: PM: enable UART3 module wakeupsKevin Hilman
UART3 is in the PER powerdomain. If PER goes idle/inactive independently of CORE, for UART3 to wakeup it must have its wakeup enable bits setup in PM_WKEN_PER. This patch enables these bits. The reason it works when PER and CORE work together is because when CORE goes inactive/retention, the IOPAD wakeups are enabled and trigger UART3 wakeup. Without this patch, when the UART inactivity timer fires for UART3, its clocks are disabled and it's unable to wakeup so will be unusable until PER is awoken by another source. Another way of testing is by keeping CORE on during suspend but allowing PER to hit retention # echo 3 > /debug/pm_debug/core_pwrdm/suspend then enter suspend # echo mem > /sys/power/state Without this patch, UART3 will be unable to wakeup the system. Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com> Signed-off-by: Tony Lindgren <tony@atomide.com>
2009-10-20omap: headers: Move remaining headers from include/mach to include/platTony Lindgren
Move the remaining headers under plat-omap/include/mach to plat-omap/include/plat. Also search and replace the files using these headers to include using the right path. This was done with: #!/bin/bash mach_dir_old="arch/arm/plat-omap/include/mach" plat_dir_new="arch/arm/plat-omap/include/plat" headers=$(cd $mach_dir_old && ls *.h) omap_dirs="arch/arm/*omap*/ \ drivers/video/omap \ sound/soc/omap" other_files="drivers/leds/leds-ams-delta.c \ drivers/mfd/menelaus.c \ drivers/mfd/twl4030-core.c \ drivers/mtd/nand/ams-delta.c" for header in $headers; do old="#include <mach\/$header" new="#include <plat\/$header" for dir in $omap_dirs; do find $dir -type f -name \*.[chS] | \ xargs sed -i "s/$old/$new/" done find drivers/ -type f -name \*omap*.[chS] | \ xargs sed -i "s/$old/$new/" for file in $other_files; do sed -i "s/$old/$new/" $file done done for header in $(ls $mach_dir_old/*.h); do git mv $header $plat_dir_new/ done Signed-off-by: Tony Lindgren <tony@atomide.com>
2009-10-05OMAP3: PM: Enable GPIO module-level wakeupsKevin Hilman
Currently, only GPIOs in the wakeup domain (GPIOs in bank 0) are enabled as wakups. This patch also enables GPIOs in the PER powerdomain (banks 2-6) to be used as possible wakeup sources. In addition, this patch ensures that all GPIO wakeups can wakeup the MPU using the PM_MPUGRPSEL_<pwrdm> registers. NOTE: this doesn't enable the individual GPIOs as wakeups, this simply enables the per-bank wakeups at the powerdomain level. This problem was discovered by Mike Chan when preventing the CORE powerdomain from going into retention/off. When CORE was allowed to hit retention, GPIO wakeups via IO pad were working fine, but when CORE remained on, GPIO module-level wakeups were not working properly. To test, prevent CORE from going inactive/retention/off, thus preventing the IO chain from being armed: # echo 3 > /debug/pm_debug/core_pwrdm/suspend This ensures that GPIO wakeups happen via module-level wakeups and not via IO pad. Tested on 3430SDP using the touchscreen GPIO (gpio 2, in WKUP) Tested on Zoom2 using the QUART interrup GPIO (gpio 102, in PER) Also, c.f. OMAP PM wiki for troubleshooting GPIO wakeup issues: http://elinux.org/OMAP_Power_Management Reported-by: Mike Chan <mikechan@google.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-10-05OMAP3: PM: USBHOST: clear wakeup events on both hostsVikram Pandita
USBHOST module has 2 fclocks (for HOST1 and HOST2), only one iclock and only a single bit in the WKST register to indicate a wakeup event. Because of the single WKST bit, we cannot know whether a wakeup event was on HOST1 or HOST2, so enable both fclocks before clearing the wakeup event to ensure both hosts can properly clear the event. Signed-off-by: Vikram Pandita <vikram.pandita@ti.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-10-05OMAP3: PM: PRCM interrupt: only handle selected PRCM interruptsPaul Walmsley
Clearing wakeup sources is now only done when the PRM indicates a wakeup source interrupt. Since we don't handle any other types of PRCM interrupts right now, warn if we get any other type of PRCM interrupt. Either code needs to be added to the PRCM interrupt handler to react to these, or these other interrupts should be masked off at init. Updated after Jon Hunter's PRCM IRQ rework by Kevin Hilman. Signed-off-by: Paul Walmsley <paul@pwsan.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-10-05OMAP3: PM: PRCM interrupt: check MPUGRPSEL registerPaul Walmsley
PM_WKST register contents should be ANDed with the contents of the MPUGRPSEL registers. Otherwise the MPU PRCM interrupt handler could wind up clearing wakeup events meant for the IVA PRCM interrupt handler. A future revision to this code should be to read a cached version of MPUGRPSEL from the powerdomain code, since PRM reads are relatively slow. Updated after Jon Hunter's PRCM IRQ change by Kevin Hilman Signed-off-by: Paul Walmsley <paul@pwsan.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-10-05OMAP3: PM: Prevent hang in prcm_interrupt_handlerJon Hunter
There are two scenarios where a race condition could result in a hang in the prcm_interrupt handler. These are: 1). Waiting for PRM_IRQSTATUS_MPU register to clear. Bit 0 of the PRM_IRQSTATUS_MPU register indicates that a wake-up event is pending for the MPU. This bit can only be cleared if the all the wake-up events latched in the various PM_WKST_x registers have been cleared. If a wake-up event occurred during the processing of the prcm interrupt handler, after the corresponding PM_WKST_x register was checked but before the PRM_IRQSTATUS_MPU was cleared, then the CPU would be stuck forever waiting for bit 0 in PRM_IRQSTATUS_MPU to be cleared. 2). Waiting for the PM_WKST_x register to clear. Some power domains have more than one wake-up source. The PM_WKST_x registers indicate the source of a wake-up event and need to be cleared after a wake-up event occurs. When the PM_WKST_x registers are read and before they are cleared, it is possible that another wake-up event could occur causing another bit to be set in one of the PM_WKST_x registers. If this did occur after reading a PM_WKST_x register then the CPU would miss this event and get stuck forever in a loop waiting for that PM_WKST_x register to clear. This patch address the above race conditions that would result in a hang. Signed-off-by: Jon Hunter <jon-hunter@ti.com> Reviewed-by: Paul Walmsley <paul@pwsan.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-09-02Merge branch 'pm-upstream/debug' of ↵Tony Lindgren
git://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux-omap-pm into for-next
2009-09-02OMAP: PM: Added suspend target state control to debugfs for OMAP3Tero Kristo
Target state can be read / programmed via files under: [debugfs]/pm_debug/[pwrdm]/suspend Signed-off-by: Tero Kristo <tero.kristo@nokia.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-09-02OMAP: PM: Add closures to clkdm_for_each and pwrdm_for_each.Peter 'p2' De Schrijver
Add some infrastructure to easily iterate over clock and power domains. Signed-off-by: Peter 'p2' De Schrijver <peter.de-schrijver@nokia.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-09-02OMAP: PM: Hook into PM countersPeter 'p2' De Schrijver
This patch modifies the clock, clockdomain and OMAP3 specific powerdomain code to call the PM counter infrastructure whenever one or more powerdomains might have changed state. Signed-off-by: Peter 'p2' De Schrijver <peter.de-schrijver@nokia.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-09-02OMAP3: PM: fix lockdep warning caused by omap3_pm_initMing Lei
This patch uses kmalloc(size,GFP_ATOMIC) instead of kmalloc(size,GFP_KERNEL) to allocate memory for instance of struct power_state in pwrdms_setup(), since it may be called by pwrdm_for_each() with irq disabled. It is a easy fix for the following lockdep warning caused by kmalloc(size,GFP_KERNEL) in pwrdms_setup(): Power Management for TI OMAP3. ------------[ cut here ]------------ WARNING: at kernel/lockdep.c:2282 lockdep_trace_alloc+0xe8/0xfc() Modules linked in: [<c0032ccc>] (unwind_backtrace+0x0/0xec) from [<c0056934>] (warn_slowpath_common+0x48/0x60) [<c0056934>] (warn_slowpath_common+0x48/0x60) from [<c007da10>] (lockdep_trace_alloc+0xe8/0xfc) [<c007da10>] (lockdep_trace_alloc+0xe8/0xfc) from [<c00cd9bc>] (kmem_cache_alloc+0x28/0x178) [<c00cd9bc>] (kmem_cache_alloc+0x28/0x178) from [<c000f184>] (pwrdms_setup+0x30/0xf8) [<c000f184>] (pwrdms_setup+0x30/0xf8) from [<c00381c4>] (pwrdm_for_each+0x64/0x84) [<c00381c4>] (pwrdm_for_each+0x64/0x84) from [<c000ef60>] (omap3_pm_init+0x3f4/0x5ac) [<c000ef60>] (omap3_pm_init+0x3f4/0x5ac) from [<c002c2c0>] (do_one_initcall+0x30/0x1d4) [<c002c2c0>] (do_one_initcall+0x30/0x1d4) from [<c00088d8>] (kernel_init+0xa4/0x118) [<c00088d8>] (kernel_init+0xa4/0x118) from [<c002ddf8>] (kernel_thread_exit+0x0/0x8) ---[ end trace 1e06f8d97dc5a19b ]--- Signed-off-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-08-05OMAP3: PM: Fix wrong sequence in suspend.Jouni Hogander
Powerdomain previous state is checked after restoring new states in suspend. This patch fixes this problem. Signed-off-by: Jouni Hogander <jouni.hogander@nokia.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-08-05OMAP3: Fixed crash bug with serial + suspendTero Kristo
It was possible for an unhandled interrupt to occur if there was incoming serial traffic during wakeup from suspend. This was caused by the code in arch-arm/mach-omap2/serial.c keeping interrupt enabled all the time, but not acking its interrupts. Applies on top of PM branch. Use the PM begin/end hooks to ensure that the "serial idle" interrupts are disabled during the suspend path. Also, since begin/end hooks are now used, use the suspend_state that is passed in the begin hook instead of the enter hook as per the platform_suspend_ops docs. Signed-off-by: Tero Kristo <tero.kristo@nokia.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-08-05OMAP3: PM: Do not build suspend code if SUSPEND is not enabledKevin Hilman
Signed-off-by: Jouni Hogander <jouni.hogander@nokia.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-08-05OMAP3: PM: prevent module wakeups from waking IVA2Kevin Hilman
By default, prevent functional wakeups from inside a module from waking up the IVA2. Let DSP Bridge code handle this when loaded. Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-08-05OMAP3: PM: Clear pending PRCM reset flags on initKevin Hilman
Any pending reset flags can prevent retention. Ensure they are all cleared during boot. Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-08-05OMAP3: PM: Ensure PRCM interrupts are cleared at bootKevin Hilman
Any pending PRCM interrupts can prevent retention. Ensure they are cleared during boot. Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-08-05OMAP2/3: PM: make PM __init calls staticKevin Hilman
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-05-28OMAP3: PM: prevent module wakeups from waking IVA2Kevin Hilman
By default, prevent functional wakeups from inside a module from waking up the IVA2. Let DSP Bridge code handle this when loaded. Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-05-28OMAP3: PM: Clear pending PRCM reset flags on initKevin Hilman
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-05-28OMAP3: PM: Ensure PRCM interrupts are cleared at bootKevin Hilman
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-05-28OMAP3: PM: Add D2D clocks and auto-idle setup to PRCM initKevin Hilman
Add D2D clocks (modem_fck, sad2d_ick, mad2d_ick) to clock framework and ensure that auto-idle bits are set for these clocks during PRCM init. Also add omap3_d2d_idle() function called durint PRCM setup which ensures D2D pins are MUX'd correctly to enable retention for standalone (no-modem) devices. Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-05-28OMAP3: PM: UART: disable clocks when idle and off-mode supportKevin Hilman
This patch allows the UART clocks to be disabled when the OMAP UARTs are inactive, thus permitting the chip to hit retention in idle. After the expiration of an activity timer, each UART is allowed to disable its clocks so the system can enter retention. The activity timer is (re)activated on any UART interrupt, UART wake event or any IO pad wakeup. The actual disable of the UART clocks is done in the 'prepare_idle' hook called from the OMAP idle loop. While the activity timer is active, the smart-idle mode of the UART is also disabled. This is due to a "feature" of the UART module that after a UART wakeup, the smart-idle mode may be entered before the UART has communicated the interrupt, or upon TX, an idle mode may be entered before the TX FIFOs are emptied. Upon suspend, the 'prepare_suspend' hook cancels any pending activity timers and allows the clocks to be disabled immediately. In addition, upon disabling clocks the UART state is saved in case of an off-mode transition while clocks are off. Special thanks to Tero Kristo for the initial ideas and first versions of UART idle support, and to Jouni Hogander for extra testing and bugfixes. Tested on OMAP3 (Beagle, RX51, SDP, EVM) and OMAP2 (n810) Cc: Tero Kristo <tero.kristo@nokia.com> Cc: Jouni Hogander <jouni.hogander@nokia.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-05-28OMAP3: PM: Force IVA2 into idle during bootupKevin Hilman
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>