Re: [alsa-devel] [RFC PATCH 25/40] soundwire: intel: use BIOS information to set clock dividers

On 25-07-19, 18:40, Pierre-Louis Bossart wrote:

The BIOS provides an Intel-specific property, let's use it to avoid hard-coded clock dividers.

Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com

drivers/soundwire/cadence_master.c | 26 ++++++++++++++++++++++---- drivers/soundwire/intel.c | 26 ++++++++++++++++++++++++++ include/linux/soundwire/sdw.h | 2 ++

ah, intel patch touching bunch of things!

3 files changed, 50 insertions(+), 4 deletions(-)

diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c index d84344e29f71..10ebcef2e84e 100644 --- a/drivers/soundwire/cadence_master.c +++ b/drivers/soundwire/cadence_master.c @@ -173,8 +173,6 @@ #define CDNS_PDI_CONFIG_PORT GENMASK(4, 0)

/* Driver defaults */

-#define CDNS_DEFAULT_CLK_DIVIDER 0 #define CDNS_DEFAULT_SSP_INTERVAL 0x18 #define CDNS_TX_TIMEOUT 2000

@@ -973,7 +971,10 @@ static u32 cdns_set_default_frame_shape(int n_rows, int n_cols) */ int sdw_cdns_init(struct sdw_cdns *cdns) {

• struct sdw_bus *bus = &cdns->bus;

• struct sdw_master_prop *prop = &bus->prop; u32 val;

• int divider; int ret;

  /* Exit clock stop */

@@ -985,9 +986,17 @@ int sdw_cdns_init(struct sdw_cdns *cdns) }

/* Set clock divider */

• divider = (prop->mclk_freq / prop->max_clk_freq) - 1; val = cdns_readl(cdns, CDNS_MCP_CLK_CTRL0);

• val |= CDNS_DEFAULT_CLK_DIVIDER;

• val |= divider; cdns_writel(cdns, CDNS_MCP_CLK_CTRL0, val);
• cdns_writel(cdns, CDNS_MCP_CLK_CTRL1, val);
• pr_err("plb: mclk %d max_freq %d divider %d register %x\n",

•       prop->mclk_freq,
  

•       prop->max_clk_freq,
  

•       divider,
  

•       val);
  

I guess you forgot to remove this!

/* Set the default frame shape */ val = cdns_set_default_frame_shape(prop->default_row, @@ -1035,6 +1044,7 @@ EXPORT_SYMBOL(sdw_cdns_init);

int cdns_bus_conf(struct sdw_bus *bus, struct sdw_bus_params *params) {

• struct sdw_master_prop *prop = &bus->prop; struct sdw_cdns *cdns = bus_to_cdns(bus); int mcp_clkctrl_off, mcp_clkctrl; int divider;

@@ -1044,7 +1054,9 @@ int cdns_bus_conf(struct sdw_bus *bus, struct sdw_bus_params *params) return -EINVAL; }

• divider = (params->max_dr_freq / params->curr_dr_freq) - 1;

• divider = prop->mclk_freq * SDW_DOUBLE_RATE_FACTOR /

• params->curr_dr_freq;
  

• divider--; /* divider is 1/(N+1) */

  if (params->next_bank) mcp_clkctrl_off = CDNS_MCP_CLK_CTRL1;

@@ -1055,6 +1067,12 @@ int cdns_bus_conf(struct sdw_bus *bus, struct sdw_bus_params *params) mcp_clkctrl |= divider; cdns_writel(cdns, mcp_clkctrl_off, mcp_clkctrl);

• pr_err("plb: mclk * 2 %d curr_dr_freq %d divider %d register %x\n",

•       prop->mclk_freq * SDW_DOUBLE_RATE_FACTOR,
  

•       params->curr_dr_freq,
  

•       divider,
  

•       mcp_clkctrl);
  

here too!

• return 0;

} EXPORT_SYMBOL(cdns_bus_conf); diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c index c718c9c67a37..796ac2bc8cea 100644 --- a/drivers/soundwire/intel.c +++ b/drivers/soundwire/intel.c @@ -917,11 +917,37 @@ static int intel_register_dai(struct sdw_intel *sdw) dais, num_dai); }

+static int sdw_master_read_intel_prop(struct sdw_bus *bus) +{

• struct sdw_master_prop *prop = &bus->prop;
• struct fwnode_handle *link;
• char name[32];
• int nval, i;
• /* Find master handle */
• snprintf(name, sizeof(name),

•  "mipi-sdw-link-%d-subproperties", bus->link_id);
  

• link = device_get_named_child_node(bus->dev, name);
• if (!link) {

• dev_err(bus->dev, "Master node %s not found\n", name);
  

• return -EIO;
  

• }
• fwnode_property_read_u32(link,

• 		 "intel-sdw-ip-clock",
  

• 		 &prop->mclk_freq);
  

• return 0;

+}

static int intel_prop_read(struct sdw_bus *bus) { /* Initialize with default handler to read all DisCo properties */ sdw_master_read_prop(bus);

• /* read Intel-specific properties */
• sdw_master_read_intel_prop(bus);
• return 0;

}

diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h index 31d1e8acf25b..b6acc436ac80 100644 --- a/include/linux/soundwire/sdw.h +++ b/include/linux/soundwire/sdw.h @@ -379,6 +379,7 @@ struct sdw_slave_prop {

• @dynamic_frame: Dynamic frame shape supported
• @err_threshold: Number of times that software may retry sending a single
• command

• • @mclk_freq: clock reference passed to SoundWire Master, in Hz.
  */

struct sdw_master_prop { u32 revision; @@ -393,6 +394,7 @@ struct sdw_master_prop { u32 default_col; bool dynamic_frame; u32 err_threshold;

• u32 mclk_freq;

Other than debug artifacts this looks sane, but can you split up the cadence and intel parts into different patches please