Re: [PATCH 2/3] ASoC: qcom: q6afe: check ADSP version when setting clocks

[Srinivas Kandagatla <srinivas.kandagatla@linaro.org>]

Thanks Otto for the patch,
some comments below

On 14/10/2023 18:26, Otto Pflüger wrote:
> There are two APIs for setting clocks: the old one that uses
> AFE_PARAM_ID_INT_DIGITAL_CDC_CLK_CONFIG and AFE_PARAM_ID_LPAIF_CLK_CONFIG,
> and the new one which uses AFE_PARAM_ID_CLOCK_SET.
> 
> ADSP firmware version 2.6 only provides the old API, while newer
> firmware versions only provide the new API.
> 
> Implement LPAIF_BIT_CLK and LPAIF_DIG_CLK for both APIs so that users
> don't have to care about the firmware version. Also fall back to
> setting AFE_PARAM_ID_INT_DIGITAL_CDC_CLK_CONFIG in q6afe_set_lpass_clock
> when setting the new Q6AFE_LPASS_CLK_ID_INTERNAL_DIGITAL_CODEC_CORE
> clock is requested to allow specifying it in the device tree on older
> platforms too.
> 
> Signed-off-by: Otto Pflüger <otto.pflueger@abscue.de>
> ---
>   sound/soc/qcom/qdsp6/q6afe.c | 81 ++++++++++++++++++++++++++++++++++++
>   1 file changed, 81 insertions(+)
> 
> diff --git a/sound/soc/qcom/qdsp6/q6afe.c b/sound/soc/qcom/qdsp6/q6afe.c
> index 91d39f6ad0bd..87bdf741e5f6 100644
> --- a/sound/soc/qcom/qdsp6/q6afe.c
> +++ b/sound/soc/qcom/qdsp6/q6afe.c
> @@ -1111,6 +1111,32 @@ int q6afe_set_lpass_clock(struct device *dev, int clk_id, int attri,
>   	struct q6afe *afe = dev_get_drvdata(dev->parent);
>   	struct afe_clk_set cset = {0,};
>   
> +	/*
> +	 * v2 clocks specified in the device tree may not be supported by the
> +	 * firmware. If this is the digital codec core clock, fall back to the
> +	 * old method for setting it.
> +	 */
> +	if (q6core_get_adsp_version() < Q6_ADSP_VERSION_2_7) {
> +		struct q6afe_port *port;
> +		struct afe_digital_clk_cfg dcfg = {0,};
> +		int ret;
> +
> +		if (clk_id != Q6AFE_LPASS_CLK_ID_INTERNAL_DIGITAL_CODEC_CORE)
> +			return -EINVAL;
> +

<---
> +		port = q6afe_port_get_from_id(dev, PRIMARY_MI2S_RX);
> +		if (IS_ERR(port))
> +			return PTR_ERR(port);
> +
> +		dcfg.i2s_cfg_minor_version = AFE_API_VERSION_I2S_CONFIG;
> +		dcfg.clk_val = freq;
> +		dcfg.clk_root = 5;
> +		ret = q6afe_set_digital_codec_core_clock(port, &dcfg);
> +
> +		q6afe_port_put(port);
--->

Could you pl explain what are we doing in this snippet?

Isn't this what is exactly done in q6afe_mi2s_set_sysclk(LPAIF_DIG_CLK...)




> +		return ret;
> +	}
> +
>   	cset.clk_set_minor_version = AFE_API_VERSION_CLOCK_SET;
>   	cset.clk_id = clk_id;
>   	cset.clk_freq_in_hz = freq;
> @@ -1124,6 +1150,41 @@ int q6afe_set_lpass_clock(struct device *dev, int clk_id, int attri,
>   }
>   EXPORT_SYMBOL_GPL(q6afe_set_lpass_clock);
>   
...

>   int q6afe_port_set_sysclk(struct q6afe_port *port, int clk_id,
>   			  int clk_src, int clk_root,
>   			  unsigned int freq, int dir)
> @@ -1133,6 +1194,26 @@ int q6afe_port_set_sysclk(struct q6afe_port *port, int clk_id,
>   	struct afe_digital_clk_cfg dcfg = {0,};
>   	int ret;
>   
> +	if (q6core_get_adsp_version() >= Q6_ADSP_VERSION_2_7) {
> +		/* Always use the new clock API on newer platforms. */
> +		switch (clk_id) {
> +		case LPAIF_DIG_CLK:
> +			clk_src = Q6AFE_LPASS_CLK_ATTRIBUTE_COUPLE_NO;
> +			clk_root = Q6AFE_LPASS_CLK_ROOT_DEFAULT;
> +			clk_id = Q6AFE_LPASS_CLK_ID_INTERNAL_DIGITAL_CODEC_CORE;
> +			break;
> +		case LPAIF_BIT_CLK:
> +			clk_src = Q6AFE_LPASS_CLK_ATTRIBUTE_COUPLE_NO;
> +			clk_root = Q6AFE_LPASS_CLK_ROOT_DEFAULT;
> +			clk_id = q6afe_get_v2_bit_clk_id(port);
> +			if (clk_id < 0)
> +				return clk_id;
> +			break;
> +		default:
> +			break;
> +		}
> +	}

This should be probably done in machine driver or q6afe-dai, not in q6afe.


> +
>   	switch (clk_id) {
>   	case LPAIF_DIG_CLK:
>   		dcfg.i2s_cfg_minor_version = AFE_API_VERSION_I2S_CONFIG;