[alsa-devel] [PATCH v2 1/3] ALSA: hda - divide controller and codec dependency on i915 gfx power well
Takashi Iwai
tiwai at suse.de
Tue Apr 28 14:59:44 CEST 2015
At Tue, 28 Apr 2015 20:43:00 +0800,
mengdong.lin at intel.com wrote:
>
> From: Mengdong Lin <mengdong.lin at intel.com>
Please don't continue in the previous thread if you send a new patch
series. It makes harder to follow.
> This patch can improve power saving for Intel platforms on which only the
> display audio codec is in the shared i915 power well:
>
> - divide the controller and codec dependency on i915 power well by adding
> flag "need_i915_power" for the chip (controller) and codec respectively.
>
> - If the controller does not need the power well, the driver will release the
> power after probe, otherwise the power will be held until the controller is
> runtime suspended or S3.
>
> - And if only the codec needs the power, its runtime PM ops will request/
> release the power.
>
> Background:
> - For Haswell/Broadwell, which has a separate HD-A controller for display audio,
> both the controller and the display codec are in the i915 power well.
>
> - For Baytrail/Braswell, the display and analog audio share the same HDA
> controller and link, and only the display codec is in the i915 power well.
>
> - For Skylake, the display and analog audio share the same HDA controller but
> use separate links. Only the display codec is in the i915 power well. And in
> legacy mode we take the two links as one. So it can follow Baytrail/Braswell.
>
> Signed-off-by: Mengdong Lin <mengdong.lin at intel.com>
>
> diff --git a/include/sound/hdaudio.h b/include/sound/hdaudio.h
> index 6a2e030..4fa2d51 100644
> --- a/include/sound/hdaudio.h
> +++ b/include/sound/hdaudio.h
> @@ -74,6 +74,7 @@ struct hdac_device {
>
> /* misc flags */
> atomic_t in_pm; /* suspend/resume being performed */
> + unsigned int need_i915_power:1; /* only codec needs i915 power */
Use bool. A bool can have a bit field, too.
Also, try not to be too specific to certain hardware.
Actually, a generic image about this operation is to control the link
power. Something like link_power_control would fit better.
> /* sysfs */
> struct hdac_widget_tree *widgets;
> @@ -184,6 +185,8 @@ struct hdac_bus_ops {
> /* get a response from the last command */
> int (*get_response)(struct hdac_bus *bus, unsigned int addr,
> unsigned int *res);
> + /* enable/disable the display power */
> + int (*display_power)(struct hdac_bus *bus, bool enable);
Also, this can be link_power() so that it can be used even for other
than HDMI/DP, if any, too.
> };
>
> /*
> @@ -308,6 +311,15 @@ static inline void snd_hdac_codec_link_down(struct hdac_device *codec)
> clear_bit(codec->addr, &codec->bus->codec_powered);
> }
>
> +/*
> + * Enable/disable the display power well, for HDMI/DP audio codecs that can be
> + * in the shared power well with GPU display engine.
> + */
> +static inline int snd_hdac_display_power(struct hdac_device *codec, bool enable)
> +{
> + return codec->bus->ops->display_power(codec->bus, enable);
Put a NULL check of bus->ops->display_power. It's not always set.
Also, the check of need_i915_power flag can be moved here.
Then move into hdac_device.c, as it becomes big as an inline function.
> +}
> +
> int snd_hdac_bus_send_cmd(struct hdac_bus *bus, unsigned int val);
> int snd_hdac_bus_get_response(struct hdac_bus *bus, unsigned int addr,
> unsigned int *res);
> diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c
> index 2d8883f..2de9e84 100644
> --- a/sound/pci/hda/hda_codec.c
> +++ b/sound/pci/hda/hda_codec.c
> @@ -857,6 +857,10 @@ void snd_hda_codec_register(struct hda_codec *codec)
> return;
> if (device_is_registered(hda_codec_dev(codec))) {
> snd_hda_register_beep_device(codec);
> +
> + if (codec->core.need_i915_power)
> + snd_hdac_display_power(&codec->core, true);
> +
> pm_runtime_enable(hda_codec_dev(codec));
> /* it was powered up in snd_hda_codec_new(), now all done */
> snd_hda_power_down(codec);
> @@ -3102,6 +3106,9 @@ static int hda_codec_runtime_suspend(struct device *dev)
> if (codec_has_clkstop(codec) && codec_has_epss(codec) &&
> (state & AC_PWRST_CLK_STOP_OK))
> snd_hdac_codec_link_down(&codec->core);
> +
> + if (codec->core.need_i915_power)
> + snd_hdac_display_power(&codec->core, false);
> return 0;
> }
>
> @@ -3109,6 +3116,9 @@ static int hda_codec_runtime_resume(struct device *dev)
> {
> struct hda_codec *codec = dev_to_hda_codec(dev);
>
> + if (codec->core.need_i915_power)
> + snd_hdac_display_power(&codec->core, true);
> +
> snd_hdac_codec_link_up(&codec->core);
> hda_call_codec_resume(codec);
> pm_runtime_mark_last_busy(dev);
> diff --git a/sound/pci/hda/hda_controller.c b/sound/pci/hda/hda_controller.c
> index e0bb623..e5bdf31 100644
> --- a/sound/pci/hda/hda_controller.c
> +++ b/sound/pci/hda/hda_controller.c
> @@ -775,9 +775,20 @@ static int azx_get_response(struct hdac_bus *bus, unsigned int addr,
> return azx_rirb_get_response(bus, addr, res);
> }
>
> +static int azx_display_power(struct hdac_bus *bus, bool enable)
> +{
> + struct azx *chip = bus_to_azx(bus);
> +
> + if (chip->ops->display_power)
> + return chip->ops->display_power(chip, enable);
> + else
> + return -EINVAL;
> +}
> +
> static const struct hdac_bus_ops bus_core_ops = {
> .command = azx_send_cmd,
> .get_response = azx_get_response,
> + .display_power = azx_display_power,
> };
>
> #ifdef CONFIG_SND_HDA_DSP_LOADER
> diff --git a/sound/pci/hda/hda_controller.h b/sound/pci/hda/hda_controller.h
> index 173bf7c..e2292e4 100644
> --- a/sound/pci/hda/hda_controller.h
> +++ b/sound/pci/hda/hda_controller.h
> @@ -89,6 +89,8 @@ struct hda_controller_ops {
> struct vm_area_struct *area);
> /* Check if current position is acceptable */
> int (*position_check)(struct azx *chip, struct azx_dev *azx_dev);
> + /* enable/disable the shared display power */
> + int (*display_power)(struct azx *chip, bool enable);
> };
>
> struct azx_pcm {
> @@ -152,6 +154,7 @@ struct azx {
> unsigned int align_buffer_size:1;
> unsigned int region_requested:1;
> unsigned int disabled:1; /* disabled by VGA-switcher */
> + unsigned int need_i915_power:1; /* both controller & display codec needs i915 power */
This doesn't have to be in hda_controller.h. hda_controller.c doesn't
refer to this at all. Better to move it into hda_intel.h.
Takashi
> #ifdef CONFIG_SND_HDA_DSP_LOADER
> struct azx_dev saved_azx_dev;
> diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
> index e615556..1b688ba 100644
> --- a/sound/pci/hda/hda_intel.c
> +++ b/sound/pci/hda/hda_intel.c
> @@ -543,6 +543,14 @@ static int azx_position_check(struct azx *chip, struct azx_dev *azx_dev)
> return 0;
> }
>
> +/* Enable/disable display power */
> +static int azx_intel_display_power(struct azx *chip, bool enable)
> +{
> + struct hda_intel *hda = container_of(chip, struct hda_intel, chip);
> +
> + return hda_display_power(hda, enable);
> +}
> +
> /*
> * Check whether the current DMA position is acceptable for updating
> * periods. Returns non-zero if it's OK.
> @@ -809,7 +817,8 @@ static int azx_suspend(struct device *dev)
>
> if (chip->msi)
> pci_disable_msi(chip->pci);
> - if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL)
> + if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL
> + && chip->need_i915_power)
> hda_display_power(hda, false);
> return 0;
> }
> @@ -829,7 +838,8 @@ static int azx_resume(struct device *dev)
> if (chip->disabled || hda->init_failed)
> return 0;
>
> - if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL) {
> + if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL
> + && chip->need_i915_power) {
> hda_display_power(hda, true);
> haswell_set_bclk(hda);
> }
> @@ -872,7 +882,8 @@ static int azx_runtime_suspend(struct device *dev)
> azx_stop_chip(chip);
> azx_enter_link_reset(chip);
> azx_clear_irq_pending(chip);
> - if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL)
> + if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL
> + && chip->need_i915_power)
> hda_display_power(hda, false);
>
> return 0;
> @@ -897,7 +908,8 @@ static int azx_runtime_resume(struct device *dev)
> if (!azx_has_pm_runtime(chip))
> return 0;
>
> - if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL) {
> + if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL
> + && chip->need_i915_power) {
> hda_display_power(hda, true);
> haswell_set_bclk(hda);
> }
> @@ -1118,7 +1130,8 @@ static int azx_free(struct azx *chip)
> release_firmware(chip->fw);
> #endif
> if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL) {
> - hda_display_power(hda, false);
> + if (chip->need_i915_power)
> + hda_display_power(hda, false);
> hda_i915_exit(hda);
> }
> kfree(hda);
> @@ -1789,6 +1802,7 @@ static const struct hda_controller_ops pci_hda_ops = {
> .substream_free_pages = substream_free_pages,
> .pcm_mmap_prepare = pcm_mmap_prepare,
> .position_check = azx_position_check,
> + .display_power = azx_intel_display_power,
> };
>
> static int azx_probe(struct pci_dev *pci,
> @@ -1882,17 +1896,26 @@ static int azx_probe_continue(struct azx *chip)
> int err;
>
> hda->probe_continued = 1;
> - /* Request power well for Haswell HDA controller and codec */
> +
> + /* Request display power well for the HDA controller or codec. For
> + * Haswell/Broadwell, both the display HDA controller and codec need
> + * this power. For other platforms, like Baytrail/Braswell, only the
> + * display codec needs the power and it can be released after probe.
> + */
> if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL) {
> + /* Assume the controller needs the power by default */
> + chip->need_i915_power = 1;
> +
> #ifdef CONFIG_SND_HDA_I915
> err = hda_i915_init(hda);
> if (err < 0)
> - goto out_free;
> + goto i915_power_fail;
> +
> err = hda_display_power(hda, true);
> if (err < 0) {
> dev_err(chip->card->dev,
> "Cannot turn on display power on i915\n");
> - goto out_free;
> + goto i915_power_fail;
> }
> #endif
> }
> @@ -1939,6 +1962,11 @@ static int azx_probe_continue(struct azx *chip)
> pm_runtime_put_noidle(&pci->dev);
>
> out_free:
> + if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL
> + && !chip->need_i915_power)
> + hda_display_power(hda, false);
> +
> +i915_power_fail:
> if (err < 0)
> hda->init_failed = 1;
> complete_all(&hda->probe_wait);
> --
> 1.9.1
>
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