Re: [PATCH v4 03/13] ALSA: hdac: Add support for hda DMA Resume capability

[Vinod Koul <vinod.koul@intel.com>]

On Fri, Dec 18, 2015 at 03:11:59PM +0530, Vinod Koul wrote:
> From: Jeeja KP <jeeja.kp@intel.com>
> 
> Skylake sports new capability of DMA resume, DRSM where we can
> resume the DMA. This capability is defined by presence of
> AZX_DRSM_CAP_ID.

Hi Takashi,

Can you please ACK this and path 4, 5 and 6 of this series, as they are
on sound/hda/. I think Mark is waiting on that..

> 
> If this capability is present, we use this capability.
> So we add:
> 
> snd_hdac_ext_stream_drsm_enable() - DMA resume caps
> snd_hdac_ext_stream_set_dpibr() - set the DMA position
> snd_hdac_ext_stream_set_lpib() - set the lpib
> 
> Signed-off-by: Jeeja KP <jeeja.kp@intel.com>
> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
> ---
>  include/sound/hda_register.h        |  9 +++++
>  include/sound/hdaudio_ext.h         | 14 ++++++++
>  sound/hda/ext/hdac_ext_controller.c |  6 ++++
>  sound/hda/ext/hdac_ext_stream.c     | 71 +++++++++++++++++++++++++++++++++++++
>  4 files changed, 100 insertions(+)
> 
> diff --git a/include/sound/hda_register.h b/include/sound/hda_register.h
> index 2ae8812d7b1a..28ac1f9a18ac 100644
> --- a/include/sound/hda_register.h
> +++ b/include/sound/hda_register.h
> @@ -230,6 +230,15 @@ enum { SDI0, SDI1, SDI2, SDI3, SDO0, SDO1, SDO2, SDO3 };
>  #define AZX_MLCTL_SPA			(1<<16)
>  #define AZX_MLCTL_CPA			23
>  
> +
> +/* registers for DMA Resume Capability Structure */
> +#define AZX_DRSM_CAP_ID			0x5
> +#define AZX_REG_DRSM_CTL		0x4
> +/* Base used to calculate the iterating register offset */
> +#define AZX_DRSM_BASE			0x08
> +/* Interval used to calculate the iterating register offset */
> +#define AZX_DRSM_INTERVAL		0x08
> +
>  /*
>   * helpers to read the stream position
>   */
> diff --git a/include/sound/hdaudio_ext.h b/include/sound/hdaudio_ext.h
> index 425af0674557..f3454950ee0b 100644
> --- a/include/sound/hdaudio_ext.h
> +++ b/include/sound/hdaudio_ext.h
> @@ -12,6 +12,7 @@
>   * @spbcap: SPIB capabilities pointer
>   * @mlcap: MultiLink capabilities pointer
>   * @gtscap: gts capabilities pointer
> + * @drsmcap: dma resume capabilities pointer
>   * @hlink_list: link list of HDA links
>   */
>  struct hdac_ext_bus {
> @@ -23,6 +24,7 @@ struct hdac_ext_bus {
>  	void __iomem *spbcap;
>  	void __iomem *mlcap;
>  	void __iomem *gtscap;
> +	void __iomem *drsmcap;
>  
>  	struct list_head hlink_list;
>  };
> @@ -72,6 +74,9 @@ enum hdac_ext_stream_type {
>   * @pplc_addr: processing pipe link stream pointer
>   * @spib_addr: software position in buffers stream pointer
>   * @fifo_addr: software position Max fifos stream pointer
> + * @dpibr_addr: DMA position in buffer resume pointer
> + * @dpib: DMA position in buffer
> + * @lpib: Linear position in buffer
>   * @decoupled: stream host and link is decoupled
>   * @link_locked: link is locked
>   * @link_prepared: link is prepared
> @@ -86,6 +91,10 @@ struct hdac_ext_stream {
>  	void __iomem *spib_addr;
>  	void __iomem *fifo_addr;
>  
> +	void __iomem *dpibr_addr;
> +
> +	u32 dpib;
> +	u32 lpib;
>  	bool decoupled:1;
>  	bool link_locked:1;
>  	bool link_prepared;
> @@ -116,6 +125,11 @@ int snd_hdac_ext_stream_set_spib(struct hdac_ext_bus *ebus,
>  				 struct hdac_ext_stream *stream, u32 value);
>  int snd_hdac_ext_stream_get_spbmaxfifo(struct hdac_ext_bus *ebus,
>  				 struct hdac_ext_stream *stream);
> +void snd_hdac_ext_stream_drsm_enable(struct hdac_ext_bus *ebus,
> +				bool enable, int index);
> +int snd_hdac_ext_stream_set_dpibr(struct hdac_ext_bus *ebus,
> +				struct hdac_ext_stream *stream, u32 value);
> +int snd_hdac_ext_stream_set_lpib(struct hdac_ext_stream *stream, u32 value);
>  
>  void snd_hdac_ext_link_stream_start(struct hdac_ext_stream *hstream);
>  void snd_hdac_ext_link_stream_clear(struct hdac_ext_stream *hstream);
> diff --git a/sound/hda/ext/hdac_ext_controller.c b/sound/hda/ext/hdac_ext_controller.c
> index 63215b17247c..556267e75591 100644
> --- a/sound/hda/ext/hdac_ext_controller.c
> +++ b/sound/hda/ext/hdac_ext_controller.c
> @@ -77,6 +77,12 @@ int snd_hdac_ext_bus_parse_capabilities(struct hdac_ext_bus *ebus)
>  			ebus->spbcap = bus->remap_addr + offset;
>  			break;
>  
> +		case AZX_DRSM_CAP_ID:
> +			/* DMA resume  capability found, handler function */
> +			dev_dbg(bus->dev, "Found DRSM capability\n");
> +			ebus->drsmcap = bus->remap_addr + offset;
> +			break;
> +
>  		default:
>  			dev_dbg(bus->dev, "Unknown capability %d\n", cur_cap);
>  			break;
> diff --git a/sound/hda/ext/hdac_ext_stream.c b/sound/hda/ext/hdac_ext_stream.c
> index cb89ec7c8147..8f30e8836818 100644
> --- a/sound/hda/ext/hdac_ext_stream.c
> +++ b/sound/hda/ext/hdac_ext_stream.c
> @@ -59,6 +59,10 @@ void snd_hdac_ext_stream_init(struct hdac_ext_bus *ebus,
>  					AZX_SPB_MAXFIFO;
>  	}
>  
> +	if (ebus->drsmcap)
> +		stream->dpibr_addr = ebus->drsmcap + AZX_DRSM_BASE +
> +					AZX_DRSM_INTERVAL * idx;
> +
>  	stream->decoupled = false;
>  	snd_hdac_stream_init(bus, &stream->hstream, idx, direction, tag);
>  }
> @@ -497,3 +501,70 @@ void snd_hdac_ext_stop_streams(struct hdac_ext_bus *ebus)
>  	}
>  }
>  EXPORT_SYMBOL_GPL(snd_hdac_ext_stop_streams);
> +
> +/**
> + * snd_hdac_ext_stream_drsm_enable - enable DMA resume for a stream
> + * @ebus: HD-audio ext core bus
> + * @enable: flag to enable/disable DRSM
> + * @index: stream index for which DRSM need to be enabled
> + */
> +void snd_hdac_ext_stream_drsm_enable(struct hdac_ext_bus *ebus,
> +				bool enable, int index)
> +{
> +	u32 mask = 0;
> +	u32 register_mask = 0;
> +	struct hdac_bus *bus = &ebus->bus;
> +
> +	if (!ebus->drsmcap) {
> +		dev_err(bus->dev, "Address of DRSM capability is NULL");
> +		return;
> +	}
> +
> +	mask |= (1 << index);
> +
> +	register_mask = readl(ebus->drsmcap + AZX_REG_SPB_SPBFCCTL);
> +
> +	mask |= register_mask;
> +
> +	if (enable)
> +		snd_hdac_updatel(ebus->drsmcap, AZX_REG_DRSM_CTL, 0, mask);
> +	else
> +		snd_hdac_updatel(ebus->drsmcap, AZX_REG_DRSM_CTL, mask, 0);
> +}
> +EXPORT_SYMBOL_GPL(snd_hdac_ext_stream_drsm_enable);
> +
> +/**
> + * snd_hdac_ext_stream_set_dpibr - sets the dpibr value of a stream
> + * @ebus: HD-audio ext core bus
> + * @stream: hdac_ext_stream
> + * @value: dpib value to set
> + */
> +int snd_hdac_ext_stream_set_dpibr(struct hdac_ext_bus *ebus,
> +				 struct hdac_ext_stream *stream, u32 value)
> +{
> +	struct hdac_bus *bus = &ebus->bus;
> +
> +	if (!ebus->drsmcap) {
> +		dev_err(bus->dev, "Address of DRSM capability is NULL");
> +		return -EINVAL;
> +	}
> +
> +	writel(value, stream->dpibr_addr);
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(snd_hdac_ext_stream_set_dpibr);
> +
> +/**
> + * snd_hdac_ext_stream_set_lpib - sets the lpib value of a stream
> + * @ebus: HD-audio ext core bus
> + * @stream: hdac_ext_stream
> + * @value: lpib value to set
> + */
> +int snd_hdac_ext_stream_set_lpib(struct hdac_ext_stream *stream, u32 value)
> +{
> +	snd_hdac_stream_writel(&stream->hstream, SD_LPIB, value);
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(snd_hdac_ext_stream_set_lpib);
> -- 
> 1.9.1
> 

-- 
~Vinod