Le mercredi 21 février 2024 à 02:27 +0000, jackson.lee a écrit : > Hello Nicolas > > > Thanks for your comment > > > Le mardi 20 février 2024 à 05:12 +0000, jackson.lee a écrit : > > > A pause is common state for media player, but our VPU could trigger an > > interrupt regardless of a player state. > > > So at a pause state if a power turns off, our driver becomes hang-up. > > > I think power on/off should be controlled in the open/close function. > > > > Please, avoid top posting, this breaks the discussion completely. Walk > > through the comments, and reply to them underneath so we can have a proper > > discussion. > > > > In our experience, and with the rework of the driver we did during up- > > streaming, there is no more un-solicited IRQ. The way the driver state > > machine has been built, when the m2m framework is idle (no jobs are active > > or pending), it means the firmware is stalled, waiting on some application > > action. Combined with a timer of course, so we don't actively > > suspend/resume, this seems adequate place to do power management. If that > > application action never occurred passed a decent delay, we can suspend. > > Later on, user actions like qbuf, will lead to > > device_run() to be called again, and it would be a good place to resume it. > > The above comment means like the below ? > The wave5_vpu_dec_finish_decode is called by IRQ if there is a decoded frame. > And at the end of the function, if there is no data queued, v4l2_m2m_job_finish is called. > You means suspend is called in that function and if app feeds new data into v4l2 driver, the device_run then is called, > In the device_run, resume is called. That is the general idea. (Note that we don't forcefully suspect, for this type of HW, we should configure a delay. Just saying in case someone miss-interpret what was written here) > > > I have a question, > If app is paused or resumed , the v4l2's vidioc_decoder_cmd is always called ? There is no indication if an app is paused / resumed. Runtime PM in fact should not depend on application actions in general. In the case of V4L2, most driver will configure a delay (like 5 seconds). If the driver has been idle (no pending work, no jobs) withing that delay, it will auto suspend. Then whenever new activity comes, like a QBUF, we resume. Nicolas > > Thanks. > > > > There is of course other places where you'll have to make sure the > > hardware is resumed, like on close, as you want to remove the instance. > > There is also small queries here and there that need to be surrounded with > > resume/put, but with the redesign, most of the HW access now take place > > inside device_run() only. > > > > Open/Close is not invalid, but it has a lot of issues, as any random > > application can endup disabling the kernel ability to save power. > > Personally, I think we should at least give it a try, and document valid > > reason not to do so if we find hardware issues. Otherwise, this sounds > > like all we care is ticking the box "this driver has runtime PM" without > > actually caring about effective power saving. > > > > Nicolas > > > > > > > > Thanks. > > > > > > > Le lundi 19 février 2024 à 04:04 +0000, jackson.lee a écrit : > > > > > Hi Nicolas > > > > > > > > > > > > > > > > This seems very unnatural. We do the get() in > > > > > > "start_streaming()", but the > > > > > > put() is only done when the device is closed, or when the driver > > > > > > is removed. As this is not balanced, you seem to have to check > > > > > > the suspended condition all over the place. > > > > > > > > > > > > I think we could aim for start_streaming()/stop_streaming() for > > > > > > your get/put placement. At least they will be bound to an > > > > > > entirely balanced > > > > API. > > > > > > But then, a media player in paused sate will prevent that device > > > > > > from being suspended. > > > > > > > > > > > > If the HW is capable of preserving enough state, and From the > > > > > > short doc I have it gives me the impression it can preserve > > > > > > that, I'd suggest to follow what hantro driver is doing. What is > > > > > > does is that it will do get() in device_run(), and put() > > > > > > whenever the job completes. This driver has been designed so > > > > > > when there is no job, it means the firmware is currently idle > > > > > > and looking for more work. So it seems like the perfect moment to > > do suspend it. > > > > > > > > > > > > > > > > Thanks your comment, > > > > > > > > > > Currently they are not balanced, > > > > > If we puts "the put functon" into the stop_streaming, our hw is > > > > > stalled > > > > until doing wake-up command, so our v4l2 device become block. > > > > > so I'd like to update the below instead of calling get at the > > > > start_streaming function. > > > > > > > > > > > > > > > @@ -1867,6 +1868,13 @@ static int wave5_vpu_open_dec(struct file > > > > > *filp) > > > > > > > > > > wave5_vdi_allocate_sram(inst->dev); > > > > > > > > > > + err = pm_runtime_resume_and_get(inst->dev->dev); > > > > > + if (err) { > > > > > + dev_err(inst->dev->dev, "decoder runtime resume > > > > failed %d\n", err); > > > > > + ret = -EINVAL; > > > > > + goto cleanup_inst; > > > > > + } > > > > > + > > > > > return 0; > > > > > > > > I guess we need to discuss the power management strategy for this > > device. > > > > If you do resume_and_get() in open(), and then put in close(), that > > > > seems balanced. But in term of power saving, it might not be very > > > > strong. If you have a media player that is set to pause and then > > > > placed in the background, you still keep the IP running. This is > > > > extremely common, since application cannot close their device > > > > without loosing the reference frames, and thus having to do extra > > > > work on resume to seek back to the previous sync point and drop > > unneeded frames. > > > > > > > > It seems like the whole point of asking the firmware to save the > > > > state and suspend is to be able to do so while there is meaningful > > > > sate in the firt place. > > > > If we are to suspend only when there is no meaningful state, we > > > > could just free all resources and power it off completely. (This is > > > > just for illustration, its probably to slow to boot the firmware at > > > > runtime) > > > > > > > > > > > > I understand you suffered lockup with a start_streaming() for > > > > resume_and_get(), and stop_streaming() for put(), this may simply > > > > indicate that some hardware access are needed between these two. Can > > > > you write down a power management plan that would effectively save > > > > power in common use cases ? We can certainly help in refactoring the > > code to make that happen. > > > > > > > > Nicolas > > > > > > > > > > > > > > > Le mercredi 31 janvier 2024 à 10:30 +0900, jackson.lee a écrit : > > > > > > > There are two device run-time PM callbacks defined in 'struct > > > > > > dev_pm_ops' > > > > > > > int (*runtime_suspend)(struct device *dev); int > > > > > > > (*runtime_resume)(struct device *dev); > > > > > > > > > > > > I wonder how useful is it to teach everyone what the generic > > > > > > 'struct dev_pm_ops' > > > > > > contains. Perhaps you simply wanted that this patch implement > > > > > > both suspend and resume ops ? > > > > > > > > > > > > > > > > > > > > Signed-off-by: Jackson Lee <jackson.lee@xxxxxxxxxxxxxxx> > > > > > > > Signed-off-by: Nas Chung <nas.chung@xxxxxxxxxxxxxxx> > > > > > > > --- > > > > > > > .../platform/chips-media/wave5/wave5-hw.c | 5 +- > > > > > > > .../chips-media/wave5/wave5-vpu-dec.c | 9 +++ > > > > > > > .../chips-media/wave5/wave5-vpu-enc.c | 9 +++ > > > > > > > .../platform/chips-media/wave5/wave5-vpu.c | 68 > > > > +++++++++++++++++++ > > > > > > > .../platform/chips-media/wave5/wave5-vpuapi.c | 7 ++ > > > > > > > .../media/platform/chips-media/wave5/wave5.h | 3 + > > > > > > > 6 files changed, 99 insertions(+), 2 deletions(-) > > > > > > > > > > > > > > diff --git > > > > > > > a/drivers/media/platform/chips-media/wave5/wave5-hw.c > > > > > > > b/drivers/media/platform/chips-media/wave5/wave5-hw.c > > > > > > > index 8ad7f3a28ae1..8aade5a38439 100644 > > > > > > > --- a/drivers/media/platform/chips-media/wave5/wave5-hw.c > > > > > > > +++ b/drivers/media/platform/chips-media/wave5/wave5-hw.c > > > > > > > @@ -503,6 +503,7 @@ int wave5_vpu_build_up_dec_param(struct > > > > > > > vpu_instance > > > > > > *inst, > > > > > > > /* This register must be reset explicitly */ > > > > > > > vpu_write_reg(inst->dev, W5_CMD_EXT_ADDR, 0); > > > > > > > vpu_write_reg(inst->dev, W5_CMD_NUM_CQ_DEPTH_M1, > > > > > > > (COMMAND_QUEUE_DEPTH - 1)); > > > > > > > + vpu_write_reg(inst->dev, W5_CMD_ERR_CONCEAL, 0); > > > > > > > > > > > > In some way, the relation between suspend and this register > > > > > > write is not obvious. If its not related, please do this in its > > own patch. > > > > > > Otherwise you want to explain why you needed this (possibly just > > > > > > in the commit message). > > > > > > > > > > > > > > > > > > > > ret = send_firmware_command(inst, W5_CREATE_INSTANCE, true, > > > > > > > NULL, > > > > > > NULL); > > > > > > > if (ret) { > > > > > > > @@ -1075,8 +1076,8 @@ int wave5_vpu_re_init(struct device > > > > > > > *dev, u8 *fw, > > > > > > size_t size) > > > > > > > return setup_wave5_properties(dev); } > > > > > > > > > > > > > > -static int wave5_vpu_sleep_wake(struct device *dev, bool > > > > > > > i_sleep_wake, > > > > > > const uint16_t *code, > > > > > > > - size_t size) > > > > > > > +int wave5_vpu_sleep_wake(struct device *dev, bool > > > > > > > +i_sleep_wake, const > > > > > > uint16_t *code, > > > > > > > + size_t size) > > > > > > > { > > > > > > > u32 reg_val; > > > > > > > struct vpu_buf *common_vb; > > > > > > > diff --git > > > > > > > a/drivers/media/platform/chips-media/wave5/wave5-vpu-dec.c > > > > > > > b/drivers/media/platform/chips-media/wave5/wave5-vpu-dec.c > > > > > > > index ef227af72348..328a7a8f26c5 100644 > > > > > > > --- a/drivers/media/platform/chips-media/wave5/wave5-vpu-dec.c > > > > > > > +++ b/drivers/media/platform/chips-media/wave5/wave5-vpu-dec.c > > > > > > > @@ -5,6 +5,7 @@ > > > > > > > * Copyright (C) 2021-2023 CHIPS&MEDIA INC > > > > > > > */ > > > > > > > > > > > > > > +#include <linux/pm_runtime.h> > > > > > > > #include "wave5-helper.h" > > > > > > > > > > > > > > #define VPU_DEC_DEV_NAME "C&M Wave5 VPU decoder" > > > > > > > @@ -1387,9 +1388,17 @@ static int > > > > > > > wave5_vpu_dec_start_streaming(struct > > > > > > > vb2_queue *q, unsigned int count > > > > > > > > > > > > > > if (q->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE && inst- > > > > > state > > > > > > > == > > > > > > VPU_INST_STATE_NONE) { > > > > > > > struct dec_open_param open_param; > > > > > > > + int err = 0; > > > > > > > > > > > > > > memset(&open_param, 0, sizeof(struct dec_open_param)); > > > > > > > > > > > > > > + err = pm_runtime_resume_and_get(inst->dev->dev); > > > > > > > + if (err) { > > > > > > > + dev_err(inst->dev->dev, "decoder runtime resume > > > > > > failed %d\n", err); > > > > > > > + ret = -EINVAL; > > > > > > > + goto return_buffers; > > > > > > > + } > > > > > > > + > > > > > > > ret = wave5_vpu_dec_allocate_ring_buffer(inst); > > > > > > > if (ret) > > > > > > > goto return_buffers; > > > > > > > diff --git > > > > > > > a/drivers/media/platform/chips-media/wave5/wave5-vpu-enc.c > > > > > > > b/drivers/media/platform/chips-media/wave5/wave5-vpu-enc.c > > > > > > > index 761775216cd4..ff73d69de41c 100644 > > > > > > > --- a/drivers/media/platform/chips-media/wave5/wave5-vpu-enc.c > > > > > > > +++ b/drivers/media/platform/chips-media/wave5/wave5-vpu-enc.c > > > > > > > @@ -5,6 +5,7 @@ > > > > > > > * Copyright (C) 2021-2023 CHIPS&MEDIA INC > > > > > > > */ > > > > > > > > > > > > > > +#include <linux/pm_runtime.h> > > > > > > > #include "wave5-helper.h" > > > > > > > > > > > > > > #define VPU_ENC_DEV_NAME "C&M Wave5 VPU encoder" > > > > > > > @@ -1387,9 +1388,17 @@ static int > > > > > > > wave5_vpu_enc_start_streaming(struct > > > > > > > vb2_queue *q, unsigned int count > > > > > > > > > > > > > > if (inst->state == VPU_INST_STATE_NONE && q->type == > > > > > > V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) { > > > > > > > struct enc_open_param open_param; > > > > > > > + int err = 0; > > > > > > > > > > > > > > memset(&open_param, 0, sizeof(struct enc_open_param)); > > > > > > > > > > > > > > + err = pm_runtime_resume_and_get(inst->dev->dev); > > > > > > > + if (err) { > > > > > > > + dev_err(inst->dev->dev, "encoder runtime resume > > > > > > failed %d\n", err); > > > > > > > + ret = -EINVAL; > > > > > > > + goto return_buffers; > > > > > > > + } > > > > > > > + > > > > > > > wave5_set_enc_openparam(&open_param, inst); > > > > > > > > > > > > > > ret = wave5_vpu_enc_open(inst, &open_param); diff -- > > > > git > > > > > > > a/drivers/media/platform/chips-media/wave5/wave5-vpu.c > > > > > > > b/drivers/media/platform/chips-media/wave5/wave5-vpu.c > > > > > > > index 0d90b5820bef..f81409740a56 100644 > > > > > > > --- a/drivers/media/platform/chips-media/wave5/wave5-vpu.c > > > > > > > +++ b/drivers/media/platform/chips-media/wave5/wave5-vpu.c > > > > > > > @@ -10,6 +10,7 @@ > > > > > > > #include <linux/clk.h> > > > > > > > #include <linux/firmware.h> > > > > > > > #include <linux/interrupt.h> > > > > > > > +#include <linux/pm_runtime.h> > > > > > > > #include "wave5-vpu.h" > > > > > > > #include "wave5-regdefine.h" > > > > > > > #include "wave5-vpuconfig.h" > > > > > > > @@ -117,6 +118,65 @@ static int wave5_vpu_load_firmware(struct > > > > > > > device > > > > > > *dev, const char *fw_name, > > > > > > > return 0; > > > > > > > } > > > > > > > > > > > > > > +static __maybe_unused int wave5_pm_suspend(struct device *dev) > > { > > > > > > > + struct vpu_device *vpu = dev_get_drvdata(dev); > > > > > > > + > > > > > > > + if (pm_runtime_suspended(dev)) > > > > > > > + return 0; > > > > > > > + > > > > > > > + wave5_vpu_sleep_wake(dev, true, NULL, 0); > > > > > > > + clk_bulk_disable_unprepare(vpu->num_clks, vpu->clks); > > > > > > > + > > > > > > > + return 0; > > > > > > > +} > > > > > > > + > > > > > > > +static __maybe_unused int wave5_pm_resume(struct device *dev) { > > > > > > > + struct vpu_device *vpu = dev_get_drvdata(dev); > > > > > > > + int ret = 0; > > > > > > > + > > > > > > > + wave5_vpu_sleep_wake(dev, false, NULL, 0); > > > > > > > + ret = clk_bulk_prepare_enable(vpu->num_clks, vpu->clks); > > > > > > > + if (ret) { > > > > > > > + dev_err(dev, "Enabling clocks, fail: %d\n", ret); > > > > > > > + return ret; > > > > > > > + } > > > > > > > + > > > > > > > + return ret; > > > > > > > +} > > > > > > > + > > > > > > > +static __maybe_unused int wave5_suspend(struct device *dev) { > > > > > > > + struct vpu_device *vpu = dev_get_drvdata(dev); > > > > > > > + struct vpu_instance *inst; > > > > > > > + > > > > > > > + list_for_each_entry(inst, &vpu->instances, list) > > > > > > > + v4l2_m2m_suspend(inst->v4l2_m2m_dev); > > > > > > > + > > > > > > > + return pm_runtime_force_suspend(dev); } > > > > > > > + > > > > > > > +static __maybe_unused int wave5_resume(struct device *dev) { > > > > > > > + struct vpu_device *vpu = dev_get_drvdata(dev); > > > > > > > + struct vpu_instance *inst; > > > > > > > + int ret = 0; > > > > > > > + > > > > > > > + ret = pm_runtime_force_resume(dev); > > > > > > > + if (ret < 0) > > > > > > > + return ret; > > > > > > > + > > > > > > > + list_for_each_entry(inst, &vpu->instances, list) > > > > > > > + v4l2_m2m_resume(inst->v4l2_m2m_dev); > > > > > > > + > > > > > > > + return ret; > > > > > > > +} > > > > > > > > > > > > The functions wave5_suspend() and wave5_resume() are not just > > > > > > "maybe_unsued" but actually never used. What was the intention ? > > > > > > Considering the usage of __maybe_unused has been such a bad > > > > > > friend for this one, could you instead bracket the functions > > > > > > with an > > > > explicit ? > > > > > > > > > > > > #ifdef CONFIG_PM > > > > > > #endif > > > > > > > > > > > > This way the compiler will have a word if you implement > > > > > > something that you forgot to actually use. > > > > > > > > > > > > > + > > > > > > > +static const struct dev_pm_ops wave5_pm_ops = { > > > > > > > + SET_RUNTIME_PM_OPS(wave5_pm_suspend, wave5_pm_resume, > > > > NULL) }; > > > > > > > + > > > > > > > static int wave5_vpu_probe(struct platform_device *pdev) { > > > > > > > int ret; > > > > > > > @@ -232,6 +292,10 @@ static int wave5_vpu_probe(struct > > > > > > > platform_device > > > > > > *pdev) > > > > > > > (match_data->flags & WAVE5_IS_DEC) ? "'DECODE'" : ""); > > > > > > > dev_info(&pdev->dev, "Product Code: 0x%x\n", dev- > > > > > product_code); > > > > > > > dev_info(&pdev->dev, "Firmware Revision: %u\n", > > > > > > > fw_revision); > > > > > > > + > > > > > > > + pm_runtime_enable(&pdev->dev); > > > > > > > + wave5_vpu_sleep_wake(&pdev->dev, true, NULL, 0); > > > > > > > + > > > > > > > return 0; > > > > > > > > > > > > > > err_enc_unreg: > > > > > > > @@ -254,6 +318,9 @@ static int wave5_vpu_remove(struct > > > > > > > platform_device > > > > > > > *pdev) { > > > > > > > struct vpu_device *dev = dev_get_drvdata(&pdev->dev); > > > > > > > > > > > > > > + pm_runtime_put_sync(&pdev->dev); > > > > > > > + pm_runtime_disable(&pdev->dev); > > > > > > > + > > > > > > > mutex_destroy(&dev->dev_lock); > > > > > > > mutex_destroy(&dev->hw_lock); > > > > > > > clk_bulk_disable_unprepare(dev->num_clks, dev->clks); @@ - > > > > 281,6 > > > > > > > +348,7 @@ static struct platform_driver wave5_vpu_driver = { > > > > > > > .driver = { > > > > > > > .name = VPU_PLATFORM_DEVICE_NAME, > > > > > > > .of_match_table = of_match_ptr(wave5_dt_ids), > > > > > > > + .pm = &wave5_pm_ops, > > > > > > > }, > > > > > > > .probe = wave5_vpu_probe, > > > > > > > .remove = wave5_vpu_remove, > > > > > > > diff --git > > > > > > > a/drivers/media/platform/chips-media/wave5/wave5-vpuapi.c > > > > > > > b/drivers/media/platform/chips-media/wave5/wave5-vpuapi.c > > > > > > > index 1a3efb638dde..f1f8e4fc8474 100644 > > > > > > > --- a/drivers/media/platform/chips-media/wave5/wave5-vpuapi.c > > > > > > > +++ b/drivers/media/platform/chips-media/wave5/wave5-vpuapi.c > > > > > > > @@ -6,6 +6,7 @@ > > > > > > > */ > > > > > > > > > > > > > > #include <linux/bug.h> > > > > > > > +#include <linux/pm_runtime.h> > > > > > > > #include "wave5-vpuapi.h" > > > > > > > #include "wave5-regdefine.h" > > > > > > > #include "wave5.h" > > > > > > > @@ -232,6 +233,9 @@ int wave5_vpu_dec_close(struct > > > > > > > vpu_instance *inst, > > > > > > > u32 *fail_res) > > > > > > > > > > > > > > wave5_vdi_free_dma_memory(vpu_dev, &p_dec_info->vb_task); > > > > > > > > > > > > > > + if (!pm_runtime_suspended(inst->dev->dev)) > > > > > > > + pm_runtime_put_sync(inst->dev->dev); > > > > > > > + > > > > > > > unlock_and_return: > > > > > > > mutex_unlock(&vpu_dev->hw_lock); > > > > > > > > > > > > > > @@ -734,6 +738,9 @@ int wave5_vpu_enc_close(struct > > > > > > > vpu_instance *inst, > > > > > > > u32 *fail_res) > > > > > > > > > > > > > > wave5_vdi_free_dma_memory(vpu_dev, &p_enc_info->vb_task); > > > > > > > > > > > > > > + if (!pm_runtime_suspended(inst->dev->dev)) > > > > > > > + pm_runtime_put_sync(inst->dev->dev); > > > > > > > > > > > > This seems very unnatural. We do the get() in > > > > > > "start_streaming()", but the > > > > > > put() is only done when the device is closed, or when the driver > > > > > > is removed. As this is not balanced, you seem to have to check > > > > > > the suspended condition all over the place. > > > > > > > > > > > > I think we could aim for start_streaming()/stop_streaming() for > > > > > > your get/put placement. At least they will be bound to an > > > > > > entirely balanced > > > > API. > > > > > > But then, a media player in paused sate will prevent that device > > > > > > from being suspended. > > > > > > > > > > > > If the HW is capable of preserving enough state, and From the > > > > > > short doc I have it gives me the impression it can preserve > > > > > > that, I'd suggest to follow what hantro driver is doing. What is > > > > > > does is that it will do get() in device_run(), and put() > > > > > > whenever the job completes. This driver has been designed so > > > > > > when there is no job, it means the firmware is currently idle > > > > > > and looking for more work. So it seems like the perfect moment to > > do suspend it. > > > > > > > > > > > > Nicolas > > > > > > > > > > > > > + > > > > > > > mutex_unlock(&vpu_dev->hw_lock); > > > > > > > > > > > > > > return 0; > > > > > > > diff --git a/drivers/media/platform/chips-media/wave5/wave5.h > > > > > > > b/drivers/media/platform/chips-media/wave5/wave5.h > > > > > > > index 063028eccd3b..6125eff938a8 100644 > > > > > > > --- a/drivers/media/platform/chips-media/wave5/wave5.h > > > > > > > +++ b/drivers/media/platform/chips-media/wave5/wave5.h > > > > > > > @@ -56,6 +56,9 @@ int wave5_vpu_get_version(struct vpu_device > > > > > > > *vpu_dev, u32 *revision); > > > > > > > > > > > > > > int wave5_vpu_init(struct device *dev, u8 *fw, size_t size); > > > > > > > > > > > > > > +int wave5_vpu_sleep_wake(struct device *dev, bool > > > > > > > +i_sleep_wake, const > > > > > > uint16_t *code, > > > > > > > + size_t size); > > > > > > > + > > > > > > > int wave5_vpu_reset(struct device *dev, enum sw_reset_mode > > > > > > > reset_mode); > > > > > > > > > > > > > > int wave5_vpu_build_up_dec_param(struct vpu_instance *inst, > > > > > > > struct dec_open_param *param); > > > > > > > > >