* [PATCH 1/3] OMAP: omap_device: fix nsec/usec conversion in latency calculations @ 2009-11-23 17:33 Kevin Hilman 2009-11-23 17:33 ` [PATCH 2/3] OMAP: omap_device: track latency in nanoseconds Kevin Hilman 2009-12-01 12:55 ` [PATCH 1/3] OMAP: omap_device: fix nsec/usec conversion in latency calculations Paul Walmsley 0 siblings, 2 replies; 6+ messages in thread From: Kevin Hilman @ 2009-11-23 17:33 UTC (permalink / raw) To: linux-omap Use usecs = nsecs / NSEC_PER_USEC; instead of usecs = nsecs * NSEC_PER_USEC; Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com> --- arch/arm/plat-omap/omap_device.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/arm/plat-omap/omap_device.c b/arch/arm/plat-omap/omap_device.c index 288fd12..722f2c8 100644 --- a/arch/arm/plat-omap/omap_device.c +++ b/arch/arm/plat-omap/omap_device.c @@ -142,7 +142,7 @@ static int _omap_device_activate(struct omap_device *od, u8 ignore_lat) read_persistent_clock(&b); c = timespec_sub(b, a); - act_lat = timespec_to_ns(&c) * NSEC_PER_USEC; + act_lat = timespec_to_ns(&c) / NSEC_PER_USEC; pr_debug("omap_device: %s: pm_lat %d: activate: elapsed time " "%llu usec\n", od->pdev.name, od->pm_lat_level, @@ -198,7 +198,7 @@ static int _omap_device_deactivate(struct omap_device *od, u8 ignore_lat) read_persistent_clock(&b); c = timespec_sub(b, a); - deact_lat = timespec_to_ns(&c) * NSEC_PER_USEC; + deact_lat = timespec_to_ns(&c) / NSEC_PER_USEC; pr_debug("omap_device: %s: pm_lat %d: deactivate: elapsed time " "%llu usec\n", od->pdev.name, od->pm_lat_level, -- 1.6.5.1 ^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 2/3] OMAP: omap_device: track latency in nanoseconds 2009-11-23 17:33 [PATCH 1/3] OMAP: omap_device: fix nsec/usec conversion in latency calculations Kevin Hilman @ 2009-11-23 17:33 ` Kevin Hilman 2009-11-23 17:33 ` [PATCH 3/3] OMAP: omap_device: optionally auto-adjust device activate/deactivate latencies Kevin Hilman 2009-12-01 12:55 ` [PATCH 2/3] OMAP: omap_device: track latency in nanoseconds Paul Walmsley 2009-12-01 12:55 ` [PATCH 1/3] OMAP: omap_device: fix nsec/usec conversion in latency calculations Paul Walmsley 1 sibling, 2 replies; 6+ messages in thread From: Kevin Hilman @ 2009-11-23 17:33 UTC (permalink / raw) To: linux-omap Rather than having to do a usecs = nsecs / NSECS_PER_USEC to track latency in usecs, just track it in nanoseconds. Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com> --- arch/arm/plat-omap/include/plat/omap_device.h | 4 ++-- arch/arm/plat-omap/omap_device.c | 8 ++++---- 2 files changed, 6 insertions(+), 6 deletions(-) diff --git a/arch/arm/plat-omap/include/plat/omap_device.h b/arch/arm/plat-omap/include/plat/omap_device.h index c504780..3b2f3a6 100644 --- a/arch/arm/plat-omap/include/plat/omap_device.h +++ b/arch/arm/plat-omap/include/plat/omap_device.h @@ -50,8 +50,8 @@ * @pm_lats: ptr to an omap_device_pm_latency table * @pm_lats_cnt: ARRAY_SIZE() of what is passed to @pm_lats * @pm_lat_level: array index of the last odpl entry executed - -1 if never - * @dev_wakeup_lat: dev wakeup latency in microseconds - * @_dev_wakeup_lat_limit: dev wakeup latency limit in usec - set by OMAP PM + * @dev_wakeup_lat: dev wakeup latency in nanoseconds + * @_dev_wakeup_lat_limit: dev wakeup latency limit in nsec - set by OMAP PM * @_state: one of OMAP_DEVICE_STATE_* (see above) * @flags: device flags * diff --git a/arch/arm/plat-omap/omap_device.c b/arch/arm/plat-omap/omap_device.c index 722f2c8..7bf665c 100644 --- a/arch/arm/plat-omap/omap_device.c +++ b/arch/arm/plat-omap/omap_device.c @@ -142,10 +142,10 @@ static int _omap_device_activate(struct omap_device *od, u8 ignore_lat) read_persistent_clock(&b); c = timespec_sub(b, a); - act_lat = timespec_to_ns(&c) / NSEC_PER_USEC; + act_lat = timespec_to_ns(&c); pr_debug("omap_device: %s: pm_lat %d: activate: elapsed time " - "%llu usec\n", od->pdev.name, od->pm_lat_level, + "%llu nsec\n", od->pdev.name, od->pm_lat_level, act_lat); WARN(act_lat > odpl->activate_lat, "omap_device: %s.%d: " @@ -198,10 +198,10 @@ static int _omap_device_deactivate(struct omap_device *od, u8 ignore_lat) read_persistent_clock(&b); c = timespec_sub(b, a); - deact_lat = timespec_to_ns(&c) / NSEC_PER_USEC; + deact_lat = timespec_to_ns(&c); pr_debug("omap_device: %s: pm_lat %d: deactivate: elapsed time " - "%llu usec\n", od->pdev.name, od->pm_lat_level, + "%llu nsec\n", od->pdev.name, od->pm_lat_level, deact_lat); WARN(deact_lat > odpl->deactivate_lat, "omap_device: %s.%d: " -- 1.6.5.1 ^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 3/3] OMAP: omap_device: optionally auto-adjust device activate/deactivate latencies 2009-11-23 17:33 ` [PATCH 2/3] OMAP: omap_device: track latency in nanoseconds Kevin Hilman @ 2009-11-23 17:33 ` Kevin Hilman 2009-11-23 18:35 ` Kevin Hilman 2009-12-01 12:55 ` [PATCH 2/3] OMAP: omap_device: track latency in nanoseconds Paul Walmsley 1 sibling, 1 reply; 6+ messages in thread From: Kevin Hilman @ 2009-11-23 17:33 UTC (permalink / raw) To: linux-omap First, this patch adds new worst-case latency values to the omap_device_pm_latency struct. Here the worst-case measured latencies for the activate and deactivate hooks are stored. In addition, add an option to auto-adjust the latency values used for device activate/deactivate. By setting a new 'OMAP_DEVICE_LATENCY_AUTO_ADJUST' flag in the omap_device_pm_latency struct, the omap_device layer automatically adjusts the activate/deactivate latencies to the worst-case measured values. Anytime a new worst-case value is found, it is printed to the console. Here is an example log during boot using UART2 s an example. After boot, the OPP is manually changed to the 125MHz OPP: [...] Freeing init memory: 128K omap_device: serial8250.2: new worst case deactivate latency 0: 30517 omap_device: serial8250.2: new worst case activate latency 0: 30517 omap_device: serial8250.2: new worst case activate latency 0: 218139648 omap_device: serial8250.2: new worst case deactivate latency 0: 61035 omap_device: serial8250.2: new worst case activate latency 0: 278076171 omap_device: serial8250.2: new worst case activate latency 0: 298614501 omap_device: serial8250.2: new worst case activate latency 0: 327331542 / # echo 125000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_setspeed omap_device: serial8250.2: new worst case deactivate latency 0: 91552 Motivation: this can be used as a technique to automatically determine the worst case latency values. The current method of printing a warning on every violation is too noisy to actually interact the console in order to set low OPP to discover latencies. Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com> --- arch/arm/plat-omap/include/plat/omap_device.h | 4 ++ arch/arm/plat-omap/omap_device.c | 41 ++++++++++++++++++++----- 2 files changed, 37 insertions(+), 8 deletions(-) diff --git a/arch/arm/plat-omap/include/plat/omap_device.h b/arch/arm/plat-omap/include/plat/omap_device.h index 3b2f3a6..e0634fe 100644 --- a/arch/arm/plat-omap/include/plat/omap_device.h +++ b/arch/arm/plat-omap/include/plat/omap_device.h @@ -132,11 +132,15 @@ int omap_device_enable_clocks(struct omap_device *od); */ struct omap_device_pm_latency { u32 deactivate_lat; + u32 deactivate_lat_worst; int (*deactivate_func)(struct omap_device *od); u32 activate_lat; + u32 activate_lat_worst; int (*activate_func)(struct omap_device *od); + u32 flags; }; +#define OMAP_DEVICE_LATENCY_AUTO_ADJUST BIT(1) /* Get omap_device pointer from platform_device pointer */ #define to_omap_device(x) container_of((x), struct omap_device, pdev) diff --git a/arch/arm/plat-omap/omap_device.c b/arch/arm/plat-omap/omap_device.c index 7bf665c..8ba12a6 100644 --- a/arch/arm/plat-omap/omap_device.c +++ b/arch/arm/plat-omap/omap_device.c @@ -148,10 +148,22 @@ static int _omap_device_activate(struct omap_device *od, u8 ignore_lat) "%llu nsec\n", od->pdev.name, od->pm_lat_level, act_lat); - WARN(act_lat > odpl->activate_lat, "omap_device: %s.%d: " - "activate step %d took longer than expected (%llu > %d)\n", - od->pdev.name, od->pdev.id, od->pm_lat_level, - act_lat, odpl->activate_lat); + if (act_lat > odpl->activate_lat) { + odpl->activate_lat_worst = act_lat; + if (odpl->flags & OMAP_DEVICE_LATENCY_AUTO_ADJUST) { + odpl->activate_lat = act_lat; + pr_warning("omap_device: %s.%d: new worst case " + "activate latency %d: %llu\n", + od->pdev.name, od->pdev.id, + od->pm_lat_level, act_lat); + } else + pr_warning("omap_device: %s.%d: activate " + "latency %d higher than exptected. " + "(%llu > %d)\n", + od->pdev.name, od->pdev.id, + od->pm_lat_level, act_lat, + odpl->activate_lat); + } od->dev_wakeup_lat -= odpl->activate_lat; } @@ -204,10 +216,23 @@ static int _omap_device_deactivate(struct omap_device *od, u8 ignore_lat) "%llu nsec\n", od->pdev.name, od->pm_lat_level, deact_lat); - WARN(deact_lat > odpl->deactivate_lat, "omap_device: %s.%d: " - "deactivate step %d took longer than expected " - "(%llu > %d)\n", od->pdev.name, od->pdev.id, - od->pm_lat_level, deact_lat, odpl->deactivate_lat); + if (deact_lat > odpl->deactivate_lat) { + odpl->deactivate_lat_worst = deact_lat; + if (odpl->flags & OMAP_DEVICE_LATENCY_AUTO_ADJUST) { + odpl->deactivate_lat = deact_lat; + pr_warning("omap_device: %s.%d: new worst case " + "deactivate latency %d: %llu\n", + od->pdev.name, od->pdev.id, + od->pm_lat_level, deact_lat); + } else + pr_warning("omap_device: %s.%d: deactivate " + "latency %d higher than exptected. " + "(%llu > %d)\n", + od->pdev.name, od->pdev.id, + od->pm_lat_level, deact_lat, + odpl->deactivate_lat); + } + od->dev_wakeup_lat += odpl->activate_lat; -- 1.6.5.1 ^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH 3/3] OMAP: omap_device: optionally auto-adjust device activate/deactivate latencies 2009-11-23 17:33 ` [PATCH 3/3] OMAP: omap_device: optionally auto-adjust device activate/deactivate latencies Kevin Hilman @ 2009-11-23 18:35 ` Kevin Hilman 0 siblings, 0 replies; 6+ messages in thread From: Kevin Hilman @ 2009-11-23 18:35 UTC (permalink / raw) To: linux-omap Kevin Hilman wrote: > First, this patch adds new worst-case latency values to the > omap_device_pm_latency struct. Here the worst-case measured latencies > for the activate and deactivate hooks are stored. > > In addition, add an option to auto-adjust the latency values used for > device activate/deactivate. > > By setting a new 'OMAP_DEVICE_LATENCY_AUTO_ADJUST' flag in the > omap_device_pm_latency struct, the omap_device layer automatically > adjusts the activate/deactivate latencies to the worst-case measured > values. > > Anytime a new worst-case value is found, it is printed to the console. > Here is an example log during boot using UART2 s an example. After > boot, the OPP is manually changed to the 125MHz OPP: > > [...] > Freeing init memory: 128K > omap_device: serial8250.2: new worst case deactivate latency 0: 30517 > omap_device: serial8250.2: new worst case activate latency 0: 30517 > omap_device: serial8250.2: new worst case activate latency 0: 218139648 > omap_device: serial8250.2: new worst case deactivate latency 0: 61035 > omap_device: serial8250.2: new worst case activate latency 0: 278076171 > omap_device: serial8250.2: new worst case activate latency 0: 298614501 > omap_device: serial8250.2: new worst case activate latency 0: 327331542 > > / # echo 125000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_setspeed > > omap_device: serial8250.2: new worst case deactivate latency 0: 91552 > > Motivation: this can be used as a technique to automatically determine > the worst case latency values. The current method of printing a > warning on every violation is too noisy to actually interact the > console in order to set low OPP to discover latencies. Another motivation for this patch is that the activate/deactivate latenices can vary depending on the idlemode of the device. While working on the UART I noticed that when using no-idle, the activate latencies were as high as several hundred msecs as shown above. When the UARTs are in smart-idle, the max latency is well under 100 usecs. Kevin ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 2/3] OMAP: omap_device: track latency in nanoseconds 2009-11-23 17:33 ` [PATCH 2/3] OMAP: omap_device: track latency in nanoseconds Kevin Hilman 2009-11-23 17:33 ` [PATCH 3/3] OMAP: omap_device: optionally auto-adjust device activate/deactivate latencies Kevin Hilman @ 2009-12-01 12:55 ` Paul Walmsley 1 sibling, 0 replies; 6+ messages in thread From: Paul Walmsley @ 2009-12-01 12:55 UTC (permalink / raw) To: Kevin Hilman; +Cc: linux-omap On Mon, 23 Nov 2009, Kevin Hilman wrote: > Rather than having to do a usecs = nsecs / NSECS_PER_USEC to > track latency in usecs, just track it in nanoseconds. > > Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com> Thanks, looks good. Will queue this up with the rest of the hwmod patches for .33. - Paul ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 1/3] OMAP: omap_device: fix nsec/usec conversion in latency calculations 2009-11-23 17:33 [PATCH 1/3] OMAP: omap_device: fix nsec/usec conversion in latency calculations Kevin Hilman 2009-11-23 17:33 ` [PATCH 2/3] OMAP: omap_device: track latency in nanoseconds Kevin Hilman @ 2009-12-01 12:55 ` Paul Walmsley 1 sibling, 0 replies; 6+ messages in thread From: Paul Walmsley @ 2009-12-01 12:55 UTC (permalink / raw) To: Kevin Hilman; +Cc: linux-omap On Mon, 23 Nov 2009, Kevin Hilman wrote: > Use > > usecs = nsecs / NSEC_PER_USEC; > > instead of > > usecs = nsecs * NSEC_PER_USEC; > > Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com> Thanks, looks good. Will queue this up with the rest of the hwmod patches for .33. - Paul ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2009-12-01 12:55 UTC | newest] Thread overview: 6+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2009-11-23 17:33 [PATCH 1/3] OMAP: omap_device: fix nsec/usec conversion in latency calculations Kevin Hilman 2009-11-23 17:33 ` [PATCH 2/3] OMAP: omap_device: track latency in nanoseconds Kevin Hilman 2009-11-23 17:33 ` [PATCH 3/3] OMAP: omap_device: optionally auto-adjust device activate/deactivate latencies Kevin Hilman 2009-11-23 18:35 ` Kevin Hilman 2009-12-01 12:55 ` [PATCH 2/3] OMAP: omap_device: track latency in nanoseconds Paul Walmsley 2009-12-01 12:55 ` [PATCH 1/3] OMAP: omap_device: fix nsec/usec conversion in latency calculations Paul Walmsley
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox