Multiple changes squashed in single patch to avoid tick-tock effect and avoid breaking compilation/bisect

1. Per the hardware documentation, all changes to MCP_CONFIG, MCP_CONTROL, MCP_CMDCTRL and MCP_PHYCTRL need to be validated with a self-clearing write to MCP_CONFIG_UPDATE. Add a helper and do the update when the CONFIG is changed.

2. Move interrupt enable after interrupt handler registration

3. Add a new helper to start the hardware bus reset with maximum duration to make sure the Slave(s) correctly detect the reset pattern and to ensure electrical conflicts can be resolved.

4. flush command FIFOs

Better error handling will be provided after interrupt disable is provided in follow-up patches.

Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com --- drivers/soundwire/cadence_master.c | 80 +++++++++++++++++++++--------- drivers/soundwire/cadence_master.h | 1 + drivers/soundwire/intel.c | 14 +++++- 3 files changed, 69 insertions(+), 26 deletions(-)

diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c index dbe386e179b4..5337ccacccd1 100644 --- a/drivers/soundwire/cadence_master.c +++ b/drivers/soundwire/cadence_master.c @@ -228,6 +228,22 @@ static int cdns_clear_bit(struct sdw_cdns *cdns, int offset, u32 value) return -EAGAIN; }

+/* + * all changes to the MCP_CONFIG, MCP_CONTROL, MCP_CMDCTRL and MCP_PHYCTRL + * need to be confirmed with a write to MCP_CONFIG_UPDATE + */ +static int cdns_update_config(struct sdw_cdns *cdns) +{ + int ret; + + ret = cdns_clear_bit(cdns, CDNS_MCP_CONFIG_UPDATE, + CDNS_MCP_CONFIG_UPDATE_BIT); + if (ret < 0) + dev_err(cdns->dev, "Config update timedout\n"); + + return ret; +} + /* * debugfs */ @@ -745,7 +761,38 @@ EXPORT_SYMBOL(sdw_cdns_thread); /* * init routines */ -static int _cdns_enable_interrupt(struct sdw_cdns *cdns) + +/** + * sdw_cdns_exit_reset() - Program reset parameters and start bus operations + * @cdns: Cadence instance + */ +int sdw_cdns_exit_reset(struct sdw_cdns *cdns) +{ + /* program maximum length reset to be safe */ + cdns_updatel(cdns, CDNS_MCP_CONTROL, + CDNS_MCP_CONTROL_RST_DELAY, + CDNS_MCP_CONTROL_RST_DELAY); + + /* use hardware generated reset */ + cdns_updatel(cdns, CDNS_MCP_CONTROL, + CDNS_MCP_CONTROL_HW_RST, + CDNS_MCP_CONTROL_HW_RST); + + /* enable bus operations with clock and data */ + cdns_updatel(cdns, CDNS_MCP_CONFIG, + CDNS_MCP_CONFIG_OP, + CDNS_MCP_CONFIG_OP_NORMAL); + + /* commit changes */ + return cdns_update_config(cdns); +} +EXPORT_SYMBOL(sdw_cdns_exit_reset); + +/** + * sdw_cdns_enable_interrupt() - Enable SDW interrupts and update config + * @cdns: Cadence instance + */ +int sdw_cdns_enable_interrupt(struct sdw_cdns *cdns) { u32 mask;

@@ -777,24 +824,8 @@ static int _cdns_enable_interrupt(struct sdw_cdns *cdns)

cdns_writel(cdns, CDNS_MCP_INTMASK, mask);

- return 0; -} - -/** - * sdw_cdns_enable_interrupt() - Enable SDW interrupts and update config - * @cdns: Cadence instance - */ -int sdw_cdns_enable_interrupt(struct sdw_cdns *cdns) -{ - int ret; - - _cdns_enable_interrupt(cdns); - ret = cdns_clear_bit(cdns, CDNS_MCP_CONFIG_UPDATE, - CDNS_MCP_CONFIG_UPDATE_BIT); - if (ret < 0) - dev_err(cdns->dev, "Config update timedout\n"); - - return ret; + /* commit changes */ + return cdns_update_config(cdns); } EXPORT_SYMBOL(sdw_cdns_enable_interrupt);

@@ -955,6 +986,10 @@ int sdw_cdns_init(struct sdw_cdns *cdns) cdns_writel(cdns, CDNS_MCP_SSP_CTRL0, CDNS_DEFAULT_SSP_INTERVAL); cdns_writel(cdns, CDNS_MCP_SSP_CTRL1, CDNS_DEFAULT_SSP_INTERVAL);

+ /* flush command FIFOs */ + cdns_updatel(cdns, CDNS_MCP_CONTROL, CDNS_MCP_CONTROL_CMD_RST, + CDNS_MCP_CONTROL_CMD_RST); + /* Set cmd accept mode */ cdns_updatel(cdns, CDNS_MCP_CONTROL, CDNS_MCP_CONTROL_CMD_ACCEPT, CDNS_MCP_CONTROL_CMD_ACCEPT); @@ -977,13 +1012,10 @@ int sdw_cdns_init(struct sdw_cdns *cdns) /* Set cmd mode for Tx and Rx cmds */ val &= ~CDNS_MCP_CONFIG_CMD;

- /* Set operation to normal */ - val &= ~CDNS_MCP_CONFIG_OP; - val |= CDNS_MCP_CONFIG_OP_NORMAL; - cdns_writel(cdns, CDNS_MCP_CONFIG, val);

- return 0; + /* commit changes */ + return cdns_update_config(cdns); } EXPORT_SYMBOL(sdw_cdns_init);

diff --git a/drivers/soundwire/cadence_master.h b/drivers/soundwire/cadence_master.h index fbabd8afd3f5..6199e71edeab 100644 --- a/drivers/soundwire/cadence_master.h +++ b/drivers/soundwire/cadence_master.h @@ -141,6 +141,7 @@ irqreturn_t sdw_cdns_thread(int irq, void *dev_id); int sdw_cdns_init(struct sdw_cdns *cdns); int sdw_cdns_pdi_init(struct sdw_cdns *cdns, struct sdw_cdns_stream_config config); +int sdw_cdns_exit_reset(struct sdw_cdns *cdns); int sdw_cdns_enable_interrupt(struct sdw_cdns *cdns);

#ifdef CONFIG_DEBUG_FS diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c index c984261fcc33..748f832e14f6 100644 --- a/drivers/soundwire/intel.c +++ b/drivers/soundwire/intel.c @@ -953,8 +953,6 @@ static int intel_probe(struct platform_device *pdev) if (ret) goto err_init;

- ret = sdw_cdns_enable_interrupt(&sdw->cdns); - /* Read the PDI config and initialize cadence PDI */ intel_pdi_init(sdw, &config); ret = sdw_cdns_pdi_init(&sdw->cdns, config); @@ -972,6 +970,18 @@ static int intel_probe(struct platform_device *pdev) goto err_init; }

+ ret = sdw_cdns_enable_interrupt(&sdw->cdns); + if (ret < 0) { + dev_err(sdw->cdns.dev, "cannot enable interrupts\n"); + goto err_init; + } + + ret = sdw_cdns_exit_reset(&sdw->cdns); + if (ret < 0) { + dev_err(sdw->cdns.dev, "unable to exit bus reset sequence\n"); + goto err_init; + } + /* Register DAIs */ ret = intel_register_dai(sdw); if (ret) {

Move code to helper for reuse in power management routines

Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com --- drivers/soundwire/intel.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c index 748f832e14f6..891cd08e6037 100644 --- a/drivers/soundwire/intel.c +++ b/drivers/soundwire/intel.c @@ -903,6 +903,15 @@ static struct sdw_master_ops sdw_intel_ops = { .post_bank_switch = intel_post_bank_switch, };

+static int intel_init(struct sdw_intel *sdw) +{ + /* Initialize shim and controller */ + intel_link_power_up(sdw); + intel_shim_init(sdw); + + return sdw_cdns_init(&sdw->cdns); +} + /* * probe and init */ @@ -945,11 +954,8 @@ static int intel_probe(struct platform_device *pdev) return 0; }

- /* Initialize shim and controller */ - intel_link_power_up(sdw); - intel_shim_init(sdw); - - ret = sdw_cdns_init(&sdw->cdns); + /* Initialize shim, controller and Cadence IP */ + ret = intel_init(sdw); if (ret) goto err_init;

The use of clock stop is not a requirement, the IP can e.g. be completely power gated and not detect any wakes while in s2idle/deep sleep.

For now clock-stop is not supported anyways so the control parameter is always false. This will be revisited when we add clock stop.

Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com --- drivers/soundwire/cadence_master.c | 15 ++++++++------- drivers/soundwire/cadence_master.h | 2 +- drivers/soundwire/intel.c | 2 +- 3 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c index d2c44bfff53a..fed21e2b2277 100644 --- a/drivers/soundwire/cadence_master.c +++ b/drivers/soundwire/cadence_master.c @@ -979,7 +979,7 @@ static u32 cdns_set_initial_frame_shape(int n_rows, int n_cols) * sdw_cdns_init() - Cadence initialization * @cdns: Cadence instance */ -int sdw_cdns_init(struct sdw_cdns *cdns) +int sdw_cdns_init(struct sdw_cdns *cdns, bool clock_stop_exit) { struct sdw_bus *bus = &cdns->bus; struct sdw_master_prop *prop = &bus->prop; @@ -987,12 +987,13 @@ int sdw_cdns_init(struct sdw_cdns *cdns) int divider; int ret;

- /* Exit clock stop */ - ret = cdns_clear_bit(cdns, CDNS_MCP_CONTROL, - CDNS_MCP_CONTROL_CLK_STOP_CLR); - if (ret < 0) { - dev_err(cdns->dev, "Couldn't exit from clock stop\n"); - return ret; + if (clock_stop_exit) { + ret = cdns_clear_bit(cdns, CDNS_MCP_CONTROL, + CDNS_MCP_CONTROL_CLK_STOP_CLR); + if (ret < 0) { + dev_err(cdns->dev, "Couldn't exit from clock stop\n"); + return ret; + } }

/* Set clock divider */ diff --git a/drivers/soundwire/cadence_master.h b/drivers/soundwire/cadence_master.h index a106aea6fe53..001457cbe5ad 100644 --- a/drivers/soundwire/cadence_master.h +++ b/drivers/soundwire/cadence_master.h @@ -138,7 +138,7 @@ extern struct sdw_master_ops sdw_cdns_master_ops; irqreturn_t sdw_cdns_irq(int irq, void *dev_id); irqreturn_t sdw_cdns_thread(int irq, void *dev_id);

-int sdw_cdns_init(struct sdw_cdns *cdns); +int sdw_cdns_init(struct sdw_cdns *cdns, bool clock_stop_exit); int sdw_cdns_pdi_init(struct sdw_cdns *cdns, struct sdw_cdns_stream_config config); int sdw_cdns_exit_reset(struct sdw_cdns *cdns); diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c index d2fd8bdca55d..99dc61021211 100644 --- a/drivers/soundwire/intel.c +++ b/drivers/soundwire/intel.c @@ -909,7 +909,7 @@ static int intel_init(struct sdw_intel *sdw) intel_link_power_up(sdw); intel_shim_init(sdw);

- return sdw_cdns_init(&sdw->cdns); + return sdw_cdns_init(&sdw->cdns, false); }

/*