diff mbox series

[1/2] soundwire: cadence_master: set frame shape and divider based on actual clk freq

Message ID 20250107015824.5046-2-yung-chuan.liao@linux.intel.com (mailing list archive)
State New
Headers show
Series soundwire: set frame shape and divider based on actual clk freq | expand

Commit Message

Bard Liao Jan. 7, 2025, 1:58 a.m. UTC 
Frame shape and curr_dr_freq could be updated by sdw_compute_bus_params().
Peripherals will set curr_dr_freq as their frequency. Managers
should do the same. Then update frame shape according to the actual
bus frequency.

Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
---
 drivers/soundwire/cadence_master.c | 24 +++++++++++++++++++++---
 1 file changed, 21 insertions(+), 3 deletions(-)

Comments

Pierre-Louis Bossart Jan. 7, 2025, 7:19 p.m. UTC | #1 
> -static void cdns_init_clock_ctrl(struct sdw_cdns *cdns)
> +static int cdns_init_clock_ctrl(struct sdw_cdns *cdns)
>  {
>  	struct sdw_bus *bus = &cdns->bus;
>  	struct sdw_master_prop *prop = &bus->prop;
>  	u32 val;
>  	u32 ssp_interval;
>  	int divider;
> +	int freq;
>  
>  	dev_dbg(cdns->dev, "mclk %d max %d row %d col %d\n",
>  		prop->mclk_freq,
> @@ -1356,13 +1357,25 @@ static void cdns_init_clock_ctrl(struct sdw_cdns *cdns)
>  		prop->default_col);
>  
>  	/* Set clock divider */
> -	divider	= (prop->mclk_freq / prop->max_clk_freq) - 1;
> +	divider	= (prop->mclk_freq * SDW_DOUBLE_RATE_FACTOR /
> +		bus->params.curr_dr_freq) - 1;
> +	freq = bus->params.curr_dr_freq >> 1;

do you actually need this intermediate variable? see below [1] ...

>  
>  	cdns_updatel(cdns, CDNS_MCP_CLK_CTRL0,
>  		     CDNS_MCP_CLK_MCLKD_MASK, divider);
>  	cdns_updatel(cdns, CDNS_MCP_CLK_CTRL1,
>  		     CDNS_MCP_CLK_MCLKD_MASK, divider);
>  
> +	/* Set frame shape base on the actual bus frequency. */
> +	if (!prop->default_frame_rate || !prop->default_row) {
> +		dev_err(cdns->dev, "Default frame_rate %d or row %d is invalid\n",
> +			prop->default_frame_rate, prop->default_row);
> +		return -EINVAL;
> +	}

maybe check the values before writing the divider registers?

> +
> +	prop->default_col = freq * SDW_DOUBLE_RATE_FACTOR /
> +			    prop->default_frame_rate / prop->default_row;

[1] ... this is the only place where 'freq' is used, and you multiply it by two after dividing it by two.

couldn't this just be:

prop->default_col = bus->params.curr_dr_freq /
		    prop->default_frame_rate / prop->default_row;
diff mbox series

Patch

diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c
index f367670ea991..a49d4e521a8f 100644
--- a/drivers/soundwire/cadence_master.c
+++ b/drivers/soundwire/cadence_master.c
@@ -1341,13 +1341,14 @@  static u32 cdns_set_initial_frame_shape(int n_rows, int n_cols)
 	return val;
 }
 
-static void cdns_init_clock_ctrl(struct sdw_cdns *cdns)
+static int cdns_init_clock_ctrl(struct sdw_cdns *cdns)
 {
 	struct sdw_bus *bus = &cdns->bus;
 	struct sdw_master_prop *prop = &bus->prop;
 	u32 val;
 	u32 ssp_interval;
 	int divider;
+	int freq;
 
 	dev_dbg(cdns->dev, "mclk %d max %d row %d col %d\n",
 		prop->mclk_freq,
@@ -1356,13 +1357,25 @@  static void cdns_init_clock_ctrl(struct sdw_cdns *cdns)
 		prop->default_col);
 
 	/* Set clock divider */
-	divider	= (prop->mclk_freq / prop->max_clk_freq) - 1;
+	divider	= (prop->mclk_freq * SDW_DOUBLE_RATE_FACTOR /
+		bus->params.curr_dr_freq) - 1;
+	freq = bus->params.curr_dr_freq >> 1;
 
 	cdns_updatel(cdns, CDNS_MCP_CLK_CTRL0,
 		     CDNS_MCP_CLK_MCLKD_MASK, divider);
 	cdns_updatel(cdns, CDNS_MCP_CLK_CTRL1,
 		     CDNS_MCP_CLK_MCLKD_MASK, divider);
 
+	/* Set frame shape base on the actual bus frequency. */
+	if (!prop->default_frame_rate || !prop->default_row) {
+		dev_err(cdns->dev, "Default frame_rate %d or row %d is invalid\n",
+			prop->default_frame_rate, prop->default_row);
+		return -EINVAL;
+	}
+
+	prop->default_col = freq * SDW_DOUBLE_RATE_FACTOR /
+			    prop->default_frame_rate / prop->default_row;
+
 	/*
 	 * Frame shape changes after initialization have to be done
 	 * with the bank switch mechanism
@@ -1375,6 +1388,8 @@  static void cdns_init_clock_ctrl(struct sdw_cdns *cdns)
 	ssp_interval = prop->default_frame_rate / SDW_CADENCE_GSYNC_HZ;
 	cdns_writel(cdns, CDNS_MCP_SSP_CTRL0, ssp_interval);
 	cdns_writel(cdns, CDNS_MCP_SSP_CTRL1, ssp_interval);
+
+	return 0;
 }
 
 /**
@@ -1408,9 +1423,12 @@  EXPORT_SYMBOL(sdw_cdns_soft_reset);
  */
 int sdw_cdns_init(struct sdw_cdns *cdns)
 {
+	int ret;
 	u32 val;
 
-	cdns_init_clock_ctrl(cdns);
+	ret = cdns_init_clock_ctrl(cdns);
+	if (ret)
+		return ret;
 
 	sdw_cdns_check_self_clearing_bits(cdns, __func__, false, 0);