From: khilman@ti.com (Kevin Hilman) Date: Tue, 08 Mar 2011 09:33:45 -0800 Subject: [PATCH 2/2] OMAP: PM: implement devices wakeup latency constraints APIs In-Reply-To: (Jean Pihet's message of "Tue, 8 Mar 2011 16:54:48 +0100") References: <1299250375-26134-1-git-send-email-j-pihet@ti.com> <1299250375-26134-3-git-send-email-j-pihet@ti.com> <87aah6xsqk.fsf@ti.com> Message-ID: <87ipvttt3a.fsf@ti.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Jean Pihet writes: > On Tue, Mar 8, 2011 at 3:15 AM, Kevin Hilman wrote: >> Jean Pihet writes: >> >>> Implement OMAP PM layer omap_pm_set_max_dev_wakeup_lat API by >>> creating similar APIs at the omap_device and omap_hwmod levels. The >>> omap_hwmod level call is the layer with access to the powerdomain >>> core, so it is the place where the powerdomain is queried to set and >>> release the constraints. >>> >>> NOTE: only works for devices which have been converted to use >>> ? ? ? omap_device/omap_hwmod. >>> >>> Longer term, we could possibly remove this API from the OMAP PM layer, >>> and instead directly use the device level API. >>> >>> The power domains get the next power state programmed directly in >>> the registers via pwrdm_wakeuplat_update_pwrst. >>> >>> Note about PM QOS: the MPU and CORE power domains get the next power >>> state via cpuidle, which get the strongest wake-up latency constraint >>> by querying PM QOS. The usage of PM QOS is temporary, until a generic >>> solution is in place. >>> >>> Based on Vibhore's original patch, adapted to omap_device, omap_hwmod >>> and PM QOS frameworks. >> >> I haven't got to a detailed review of this code yet, but did do some >> experiements and have some general comments on the code/design to get >> started. >> >> Also, I had a problem doing a real dumb test until I figured out the >> problem with the init sequence. ?I tried setting a constraint in the >> device init code for UART (mach-omap2/serial.c:omap_serial_init_port()), >> and then I realized that that runs before >> mach-omap2/pm34xx.c:pwrdms_setup() which also calls >> omap_set_pwrdm_state() for each powerdomain to initialize. > > Do we need to change the behavior at init? > I think so. At a minimum, it should be documented somewhere that the constraints API cannot be used before pwrdms_setup(). But since that happens much later in the boot process than device init code, that might be too strict. >> Also, for debug purposes, it might be useful to have a per-device sysfs >> interface to setting this wakeup latency constraint. ?Something like >> >> ? /sys/devices/platform/omap/.../power/wakeup_latency > I do not see this as a debug interface but rather an API to the user space. > If that is the case there are some issues to deal with, cf. below. By debug, I was thinking under '#ifdef CONFIG_PM_DEBUG'. Even if you did this as a separate patch that we did not try to get upstream, it would be extremely valuable for testing this framework. >> I'm not sure exactly what to set the requesting device to though. > And also, how to track the requesters? PM QOS is using a /dev node > that must be kept open as long as the constraints remains valid. A dummy device could be created for all sysfs requesters since you would want subsequent writes to override previous ones. >> As far as implementation goes, you've so far implemented only wakeup >> latencies, but not througput. ?When you implement throughput you will >> have to duplicate large parts of this code and data structures for >> throughput, and if ever add some other constraint (frequency, voltage) >> it would need to be duplicated again. >> >> Maybe now is the time to consider an interface to add a generic >> per-device constraint, with a type (latency, throughput, etc.), or >> "class" as it's called in PM QoS. ?For now the type/class does not need >> to be exposed externally, but will make implementing new constraint >> types much easer. > Ok that makes sense. > In the current patch the constraints plist is stored inside the > powerdomain structure. This does not apply to throughput, frequency > and voltage constraints. > Should the list constraint be managed in the OMAP PM layer instead of > in the power domain code? If so where to store the constraints? I was thinking at the omap_device layer, where there would be a constraint plist managed for each class of constraint. >> Some other comments below... >> >>> Signed-off-by: Jean Pihet >>> Cc: Vibhore Vardhan >>> --- >>> Based on khilman's pm-core branch >>> >>> ?arch/arm/mach-omap2/omap_hwmod.c ? ? ? ? ? ? ?| ? 62 ++++++++- >>> ?arch/arm/mach-omap2/powerdomain.c ? ? ? ? ? ? | ?197 +++++++++++++++++++++++++ >>> ?arch/arm/mach-omap2/powerdomain.h ? ? ? ? ? ? | ? 39 +++++- >>> ?arch/arm/mach-omap2/powerdomains3xxx_data.c ? | ? 60 ++++++++ >>> ?arch/arm/plat-omap/include/plat/omap_device.h | ? ?2 + >>> ?arch/arm/plat-omap/include/plat/omap_hwmod.h ?| ? ?2 + >>> ?arch/arm/plat-omap/omap-pm-constraints.c ? ? ?| ?121 +++++++-------- >>> ?arch/arm/plat-omap/omap_device.c ? ? ? ? ? ? ?| ? 28 ++++ >>> ?8 files changed, 446 insertions(+), 65 deletions(-) >>> >>> diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c >>> index 028efda..bad8248 100644 >>> --- a/arch/arm/mach-omap2/omap_hwmod.c >>> +++ b/arch/arm/mach-omap2/omap_hwmod.c >>> @@ -142,6 +142,7 @@ >>> ?#include "powerdomain.h" >>> ?#include >>> ?#include >>> +#include >>> ?#include >>> >>> ?#include "cm2xxx_3xxx.h" >>> @@ -2267,10 +2268,69 @@ ohsps_unlock: >>> ?} >>> >>> ?/** >>> + * omap_hwmod_set_max_dev_wakeup_lat - set a device wake-up constraint >>> + * @oh: the device of @oh to set a constraint on. >>> + * @req_oh: the device of @req_oh is the requester of the constraint. >>> + * @t: wakeup latency constraint (us). -1 removes the existing constraint. >>> + * >>> + * Query the powerdomain of @oh to set/release the wake-up constraint. >>> + * @oh is used to determine which power domain to set a constraint on. >>> + * @req_oh is used to record the requester for later update or removal >>> + * of a constraint. >>> + * >>> + * Returns -EINVAL if @oh or @req_oh have no power domain, or the return >>> + * code from the pwrdm function (pwrdm_wakeuplat_set/release_constraint) >>> + * of the powerdomain assocated with @oh. >>> + */ >>> +int omap_hwmod_set_max_dev_wakeup_lat(struct omap_hwmod *req_oh, >>> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? struct omap_hwmod *oh, long t) >>> +{ >>> + ? ? struct device *req_dev; >>> + ? ? struct platform_device *req_pdev; >>> + ? ? struct powerdomain *pwrdm; >>> + >>> + ? ? pwrdm = omap_hwmod_get_pwrdm(oh); >>> + >>> + ? ? /* Catch devices with undefined powerdomains */ >>> + ? ? if (!PTR_ERR(pwrdm)) { >>> + ? ? ? ? ? ? pr_err("omap_hwmod: Error: could not find parent " >>> + ? ? ? ? ? ? ? ? ? ? "powerdomain for %s\n", oh->name); >>> + ? ? ? ? ? ? return -EINVAL; >>> + ? ? } >>> + >>> + ? ? req_pdev = &(req_oh->od->pdev); >>> + ? ? if (!PTR_ERR(req_pdev)) { >>> + ? ? ? ? ? ? pr_err("omap_hwmod: Error: pdev not found for oh %s\n", >>> + ? ? ? ? ? ? ? ? ? ?oh->name); >>> + ? ? ? ? ? ? return -EINVAL; >>> + ? ? } >>> + >>> + ? ? req_dev = &(req_pdev->dev); >>> + ? ? if (!PTR_ERR(req_dev)) { >>> + ? ? ? ? ? ? pr_err("omap_hwmod: Error: device not found for oh %s\n", >>> + ? ? ? ? ? ? ? ? ? ?oh->name); >>> + ? ? ? ? ? ? return -EINVAL; >>> + ? ? } >>> + >>> + ? ? /* Call set/release_constraint for the given pwrdm */ >>> + ? ? if (t == -1) { >>> + ? ? ? ? ? ? pr_debug("omap_hwmod: remove max device latency constraint: " >>> + ? ? ? ? ? ? ? ? ? ? ?"oh %s, pwrdm %s, req by oh %s\n", >>> + ? ? ? ? ? ? ? ? ? ? ?oh->name, pwrdm->name, req_oh->name); >>> + ? ? } else { >>> + ? ? ? ? ? ? pr_debug("omap_hwmod: add max device latency constraint: " >>> + ? ? ? ? ? ? ? ? ? ? ?"oh %s, t = %ld usec, pwrdm %s, req by oh %s\n", >>> + ? ? ? ? ? ? ? ? ? ? ?oh->name, t, pwrdm->name, req_oh->name); >>> + ? ? } >>> + >>> + ? ? return pwrdm_wakeuplat_set_constraint(pwrdm, req_dev, t); >>> +} >>> + >>> +/** >>> ? * omap_hwmod_get_context_loss_count - get lost context count >>> ? * @oh: struct omap_hwmod * >>> ? * >>> - * Query the powerdomain of of @oh to get the context loss >>> + * Query the powerdomain of @oh to get the context loss >>> ? * count for this device. >>> ? * >>> ? * Returns the context loss count of the powerdomain assocated with @oh >>> diff --git a/arch/arm/mach-omap2/powerdomain.c b/arch/arm/mach-omap2/powerdomain.c >>> index eaed0df..6fb4741 100644 >>> --- a/arch/arm/mach-omap2/powerdomain.c >>> +++ b/arch/arm/mach-omap2/powerdomain.c >>> @@ -19,6 +19,8 @@ >>> ?#include >>> ?#include >>> ?#include >>> +#include >>> + >>> ?#include "cm2xxx_3xxx.h" >>> ?#include "prcm44xx.h" >>> ?#include "cm44xx.h" >>> @@ -103,6 +105,13 @@ static int _pwrdm_register(struct powerdomain *pwrdm) >>> ? ? ? pwrdm->state = pwrdm_read_pwrst(pwrdm); >>> ? ? ? pwrdm->state_counter[pwrdm->state] = 1; >>> >>> + ? ? /* Initialize priority ordered list for wakeup latency constraint */ >>> + ? ? spin_lock_init(&pwrdm->wakeuplat_lock); >>> + ? ? plist_head_init(&pwrdm->wakeuplat_dev_list, &pwrdm->wakeuplat_lock); >>> + >>> + ? ? /* res_mutex protects res_list add and del ops */ >>> + ? ? mutex_init(&pwrdm->wakeuplat_mutex); >>> + >>> ? ? ? pr_debug("powerdomain: registered %s\n", pwrdm->name); >>> >>> ? ? ? return 0; >>> @@ -176,6 +185,74 @@ static int _pwrdm_post_transition_cb(struct powerdomain *pwrdm, void *unused) >>> ? ? ? return 0; >>> ?} >>> >>> +/** >>> + * pwrdm_wakeuplat_update_pwrst - Update power domain power state if needed >>> + * @pwrdm: struct powerdomain * to which requesting device belongs to. >>> + * >>> + * Finds the minimum allowed wake-up latency value from all entries >>> + * in the list and the power domain power state needing the constraint. >>> + * Programs a new target state if it is different from current power state. >>> + * >>> + * Only OMAP3xxx is supported for now >>> + * >>> + * Returns 0 upon success. >>> + */ >>> +static int pwrdm_wakeuplat_update_pwrst(struct powerdomain *pwrdm) >>> +{ >>> + ? ? struct plist_node *node; >>> + ? ? int ret = 0, new_state; >>> + ? ? long min_latency = -1; >>> + >>> + ? ? /* Find the strongest constraint from the plist */ >>> + ? ? if (!plist_head_empty(&pwrdm->wakeuplat_dev_list)) { >>> + ? ? ? ? ? ? node = plist_first(&pwrdm->wakeuplat_dev_list); >>> + ? ? ? ? ? ? min_latency = node->prio; >>> + ? ? } >>> + >>> + ? ? /* Find power state with wakeup latency < minimum constraint. */ >>> + ? ? for (new_state = 0x0; new_state < PWRDM_MAX_PWRSTS; new_state++) { >>> + ? ? ? ? ? ? if (min_latency == -1 || >>> + ? ? ? ? ? ? ? ? pwrdm->wakeup_lat[new_state] <= min_latency) >>> + ? ? ? ? ? ? ? ? ? ? break; >>> + ? ? } >>> + >>> + ? ? switch (new_state) { >>> + ? ? case PWRDM_FUNC_PWRST_OFF: >>> + ? ? ? ? ? ? new_state = PWRDM_POWER_OFF; >>> + ? ? ? ? ? ? break; >>> + ? ? case PWRDM_FUNC_PWRST_OSWR: >>> + ? ? ? ? ? ? if (cpu_is_omap34xx()) >>> + ? ? ? ? ? ? ? ? ? ? pwrdm_set_logic_retst(pwrdm, PWRDM_POWER_OFF); >> >> cpu_is_* checks here aren't right. >> >> You should use SoC specific function pointers as are done for many of the >> other powerdomain calls after Rajendra's splitup series. > The cpu_is_* tests are not related to the SoC specific function > pointers but rather to the comment in the function description 'Only > OMAP3xxx is supported for now'. > In fact the function that are conditionally called > (pwrdm_set_logic_retst and omap_set_pwrdm_state) are correctly using > the SoC specific pointers. > > Is this test needed? If so is it the correct way to do it? Right, I think you can just drop the cpu_is_* checks here since as you pointed out, the called functions already handle SoC specifics. >> >>> + ? ? ? ? ? ? new_state = PWRDM_POWER_RET; >>> + ? ? ? ? ? ? break; >>> + ? ? case PWRDM_FUNC_PWRST_CSWR: >>> + ? ? ? ? ? ? if (cpu_is_omap34xx()) >>> + ? ? ? ? ? ? ? ? ? ? pwrdm_set_logic_retst(pwrdm, PWRDM_POWER_RET); >>> + ? ? ? ? ? ? new_state = PWRDM_POWER_RET; >>> + ? ? ? ? ? ? break; >>> + ? ? case PWRDM_FUNC_PWRST_ON: >>> + ? ? ? ? ? ? new_state = PWRDM_POWER_ON; >>> + ? ? ? ? ? ? break; >>> + ? ? default: >>> + ? ? ? ? ? ? pr_warn("powerdomain: requested latency constraint not " >>> + ? ? ? ? ? ? ? ? ? ? "supported %s set to ON state\n", pwrdm->name); >>> + ? ? ? ? ? ? new_state = PWRDM_POWER_ON; >>> + ? ? ? ? ? ? break; >>> + ? ? } >>> + >>> + ? ? if (pwrdm_read_pwrst(pwrdm) != new_state) { >>> + ? ? ? ? ? ? if (cpu_is_omap34xx()) >>> + ? ? ? ? ? ? ? ? ? ? ret = omap_set_pwrdm_state(pwrdm, new_state); >>> + ? ? } >>> + >>> + ? ? pr_debug("powerdomain: %s pwrst: curr=%d, prev=%d next=%d " >>> + ? ? ? ? ? ? ?"min_latency=%ld, set_state=%d\n", pwrdm->name, >>> + ? ? ? ? ? ? ?pwrdm_read_pwrst(pwrdm), pwrdm_read_prev_pwrst(pwrdm), >>> + ? ? ? ? ? ? ?pwrdm_read_next_pwrst(pwrdm), min_latency, new_state); >>> + >>> + ? ? return ret; >>> +} >>> + >> >> [...] >> >>> diff --git a/arch/arm/mach-omap2/powerdomains3xxx_data.c b/arch/arm/mach-omap2/powerdomains3xxx_data.c >>> index e1bec56..4f7e44d 100644 >>> --- a/arch/arm/mach-omap2/powerdomains3xxx_data.c >>> +++ b/arch/arm/mach-omap2/powerdomains3xxx_data.c >>> @@ -52,6 +52,12 @@ static struct powerdomain iva2_pwrdm = { >>> ? ? ? ? ? ? ? [2] = PWRSTS_OFF_ON, >>> ? ? ? ? ? ? ? [3] = PWRDM_POWER_ON, >>> ? ? ? }, >>> + ? ? .wakeup_lat = { >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_OFF] = 1100, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_OSWR] = UNSUP_STATE, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_CSWR] = 350, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_ON] = 0, >>> + ? ? }, >>> ?}; >>> >>> ?static struct powerdomain mpu_3xxx_pwrdm = { >>> @@ -68,6 +74,12 @@ static struct powerdomain mpu_3xxx_pwrdm = { >>> ? ? ? .pwrsts_mem_on ? ?= { >>> ? ? ? ? ? ? ? [0] = PWRSTS_OFF_ON, >>> ? ? ? }, >>> + ? ? .wakeup_lat = { >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_OFF] = 95, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_OSWR] = UNSUP_STATE, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_CSWR] = 45, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_ON] = 0, >>> + ? ? }, >>> ?}; >>> >>> ?/* >>> @@ -98,6 +110,12 @@ static struct powerdomain core_3xxx_pre_es3_1_pwrdm = { >>> ? ? ? ? ? ? ? [0] = PWRSTS_OFF_RET_ON, /* MEM1ONSTATE */ >>> ? ? ? ? ? ? ? [1] = PWRSTS_OFF_RET_ON, /* MEM2ONSTATE */ >>> ? ? ? }, >>> + ? ? .wakeup_lat = { >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_OFF] = 100, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_OSWR] = UNSUP_STATE, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_CSWR] = 60, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_ON] = 0, >>> + ? ? }, >>> ?}; >>> >>> ?static struct powerdomain core_3xxx_es3_1_pwrdm = { >>> @@ -121,6 +139,12 @@ static struct powerdomain core_3xxx_es3_1_pwrdm = { >>> ? ? ? ? ? ? ? [0] = PWRSTS_OFF_RET_ON, /* MEM1ONSTATE */ >>> ? ? ? ? ? ? ? [1] = PWRSTS_OFF_RET_ON, /* MEM2ONSTATE */ >>> ? ? ? }, >>> + ? ? .wakeup_lat = { >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_OFF] = 100, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_OSWR] = UNSUP_STATE, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_CSWR] = 60, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_ON] = 0, >>> + ? ? }, >>> ?}; >>> >>> ?static struct powerdomain dss_pwrdm = { >>> @@ -136,6 +160,12 @@ static struct powerdomain dss_pwrdm = { >>> ? ? ? .pwrsts_mem_on ? ?= { >>> ? ? ? ? ? ? ? [0] = PWRDM_POWER_ON, ?/* MEMONSTATE */ >>> ? ? ? }, >>> + ? ? .wakeup_lat = { >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_OFF] = 70, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_OSWR] = UNSUP_STATE, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_CSWR] = 20, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_ON] = 0, >>> + ? ? }, >>> ?}; >>> >>> ?/* >>> @@ -157,6 +187,12 @@ static struct powerdomain sgx_pwrdm = { >>> ? ? ? .pwrsts_mem_on ? ?= { >>> ? ? ? ? ? ? ? [0] = PWRDM_POWER_ON, ?/* MEMONSTATE */ >>> ? ? ? }, >>> + ? ? .wakeup_lat = { >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_OFF] = 1000, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_OSWR] = UNSUP_STATE, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_CSWR] = UNSUP_STATE, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_ON] = 0, >>> + ? ? }, >>> ?}; >>> >>> ?static struct powerdomain cam_pwrdm = { >>> @@ -172,6 +208,12 @@ static struct powerdomain cam_pwrdm = { >>> ? ? ? .pwrsts_mem_on ? ?= { >>> ? ? ? ? ? ? ? [0] = PWRDM_POWER_ON, ?/* MEMONSTATE */ >>> ? ? ? }, >>> + ? ? .wakeup_lat = { >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_OFF] = 850, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_OSWR] = UNSUP_STATE, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_CSWR] = 35, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_ON] = 0, >>> + ? ? }, >>> ?}; >>> >>> ?static struct powerdomain per_pwrdm = { >>> @@ -187,6 +229,12 @@ static struct powerdomain per_pwrdm = { >>> ? ? ? .pwrsts_mem_on ? ?= { >>> ? ? ? ? ? ? ? [0] = PWRDM_POWER_ON, ?/* MEMONSTATE */ >>> ? ? ? }, >>> + ? ? .wakeup_lat = { >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_OFF] = 200, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_OSWR] = UNSUP_STATE, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_CSWR] = 110, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_ON] = 0, >>> + ? ? }, >>> ?}; >>> >>> ?static struct powerdomain emu_pwrdm = { >>> @@ -201,6 +249,12 @@ static struct powerdomain neon_pwrdm = { >>> ? ? ? .omap_chip ? ? ? ?= OMAP_CHIP_INIT(CHIP_IS_OMAP3430), >>> ? ? ? .pwrsts ? ? ? ? ? = PWRSTS_OFF_RET_ON, >>> ? ? ? .pwrsts_logic_ret = PWRDM_POWER_RET, >>> + ? ? .wakeup_lat = { >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_OFF] = 200, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_OSWR] = UNSUP_STATE, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_CSWR] = 35, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_ON] = 0, >>> + ? ? }, >>> ?}; >>> >>> ?static struct powerdomain usbhost_pwrdm = { >>> @@ -223,6 +277,12 @@ static struct powerdomain usbhost_pwrdm = { >>> ? ? ? .pwrsts_mem_on ? ?= { >>> ? ? ? ? ? ? ? [0] = PWRDM_POWER_ON, ?/* MEMONSTATE */ >>> ? ? ? }, >>> + ? ? .wakeup_lat = { >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_OFF] = 800, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_OSWR] = UNSUP_STATE, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_CSWR] = 150, >>> + ? ? ? ? ? ? [PWRDM_FUNC_PWRST_ON] = 0, >>> + ? ? }, >>> ?}; >> >> A summary about where the latency numbers for each powerdomain come from >> would be useful. > Ok > >> >> [...] >> >>> @@ -87,64 +60,86 @@ int omap_pm_set_min_bus_tput(struct device *dev, u8 agent_id, unsigned long r) >>> ? ? ? return 0; >>> ?} >>> >>> +/* >>> + * omap_pm_set_max_dev_wakeup_lat - set/release devices wake-up latency >>> + * constraints >>> + */ >>> ?int omap_pm_set_max_dev_wakeup_lat(struct device *req_dev, struct device *dev, >>> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?long t) >>> ?{ >>> + ? ? struct platform_device *pdev, *req_pdev; >>> + ? ? int ret = 0; >>> + >>> ? ? ? if (!req_dev || !dev || t < -1) { >>> ? ? ? ? ? ? ? WARN(1, "OMAP PM: %s: invalid parameter(s)", __func__); >>> ? ? ? ? ? ? ? return -EINVAL; >>> + ? ? } >>> + >>> + ? ? /* Look for the platform devices */ >>> + ? ? pdev = to_platform_device(dev); >>> + ? ? req_pdev = to_platform_device(req_dev); >>> + >>> + ? ? /* Try to catch non platform devices. */ >>> + ? ? if ((pdev->name == NULL) || (req_pdev->name == NULL)) { >>> + ? ? ? ? ? ? pr_err("OMAP-PM set_wakeup_lat: Error: platform devices " >>> + ? ? ? ? ? ? ? ? ? ?"not valid\n"); >>> + ? ? ? ? ? ? return -EINVAL; >>> + ? ? } else { >>> + ? ? ? ? ? ? /* Call the omap_device API */ >>> + ? ? ? ? ? ? ret = omap_device_set_max_dev_wakeup_lat(req_pdev, pdev, t); >>> + ? ? } >> >> I don't think a NULL name check is the right sanity check here. ?WHat >> you really need to know is whether the target device is an omap_device. >> The requesting device can be anything (I think.) >> >> Here's a simpler check: >> >> ? ? ? ?if (pdev->dev->parent == &omap_device_parent) >> ? ? ? ? ? ? ? ?ret = omap_device_set_max_dev_wakeup_lat(req_pdev, pdev, t); >> ? ? ? ?else >> ? ? ? ? ? ? ? ?... > Ok I will use this test. Note: the dev parameter is already checked > for NULL above. > > Also I think the requester parameter needs to keep the device* type > across all layers. In any case only this type is used by the low level > code (in powerdomain.c). This allows for any device (i.e. that does > not necessarily have an associated omap_device) to request > constraints. > What do you think? I agree that the only the target device needs to be an omap_device, the requester can be any device. Kevin