From 9ce978567b108f152c0f16ccc3259bbdb41404e8 Mon Sep 17 00:00:00 2001 From: Pierre-Louis Bossart Date: Mon, 6 Mar 2023 14:42:13 -0600 Subject: [PATCH 1/4] soundwire: intel_bus_common: enable interrupts last It's not clear why we enabled interrupts in the Cadence IP first. The logical programming sequence should be to first start the bus, and only second to enable the interrupts. Signed-off-by: Pierre-Louis Bossart --- drivers/soundwire/intel_bus_common.c | 57 +++++++++++++--------------- 1 file changed, 26 insertions(+), 31 deletions(-) diff --git a/drivers/soundwire/intel_bus_common.c b/drivers/soundwire/intel_bus_common.c index f180e3bea9897c..901d4f5736c18e 100644 --- a/drivers/soundwire/intel_bus_common.c +++ b/drivers/soundwire/intel_bus_common.c @@ -16,12 +16,6 @@ int intel_start_bus(struct sdw_intel *sdw) struct sdw_bus *bus = &cdns->bus; int ret; - ret = sdw_cdns_enable_interrupt(cdns, true); - if (ret < 0) { - dev_err(dev, "%s: cannot enable interrupts: %d\n", __func__, ret); - return ret; - } - /* * follow recommended programming flows to avoid timeouts when * gsync is enabled @@ -32,30 +26,33 @@ int intel_start_bus(struct sdw_intel *sdw) ret = sdw_cdns_init(cdns); if (ret < 0) { dev_err(dev, "%s: unable to initialize Cadence IP: %d\n", __func__, ret); - goto err_interrupt; + return ret; } ret = sdw_cdns_exit_reset(cdns); if (ret < 0) { dev_err(dev, "%s: unable to exit bus reset sequence: %d\n", __func__, ret); - goto err_interrupt; + return ret; } if (bus->multi_link) { ret = sdw_intel_sync_go(sdw); if (ret < 0) { dev_err(dev, "%s: sync go failed: %d\n", __func__, ret); - goto err_interrupt; + return ret; } } + + ret = sdw_cdns_enable_interrupt(cdns, true); + if (ret < 0) { + dev_err(dev, "%s: cannot enable interrupts: %d\n", __func__, ret); + return ret; + } + sdw_cdns_check_self_clearing_bits(cdns, __func__, true, INTEL_MASTER_RESET_ITERATIONS); return 0; - -err_interrupt: - sdw_cdns_enable_interrupt(cdns, false); - return ret; } int intel_start_bus_after_reset(struct sdw_intel *sdw) @@ -86,12 +83,6 @@ int intel_start_bus_after_reset(struct sdw_intel *sdw) status = SDW_UNATTACH_REQUEST_MASTER_RESET; sdw_clear_slave_status(bus, status); - ret = sdw_cdns_enable_interrupt(cdns, true); - if (ret < 0) { - dev_err(dev, "cannot enable interrupts during resume\n"); - return ret; - } - /* * follow recommended programming flows to avoid * timeouts when gsync is enabled @@ -115,31 +106,36 @@ int intel_start_bus_after_reset(struct sdw_intel *sdw) ret = sdw_cdns_clock_restart(cdns, !clock_stop0); if (ret < 0) { dev_err(dev, "unable to restart clock during resume\n"); - goto err_interrupt; + if (!clock_stop0) + sdw_cdns_enable_interrupt(cdns, false); + return ret; } if (!clock_stop0) { ret = sdw_cdns_exit_reset(cdns); if (ret < 0) { dev_err(dev, "unable to exit bus reset sequence during resume\n"); - goto err_interrupt; + return ret; } if (bus->multi_link) { ret = sdw_intel_sync_go(sdw); if (ret < 0) { dev_err(sdw->cdns.dev, "sync go failed during resume\n"); - goto err_interrupt; + return ret; } } + + ret = sdw_cdns_enable_interrupt(cdns, true); + if (ret < 0) { + dev_err(dev, "cannot enable interrupts during resume\n"); + return ret; + } + } sdw_cdns_check_self_clearing_bits(cdns, __func__, true, INTEL_MASTER_RESET_ITERATIONS); return 0; - -err_interrupt: - sdw_cdns_enable_interrupt(cdns, false); - return ret; } void intel_check_clock_stop(struct sdw_intel *sdw) @@ -158,16 +154,15 @@ int intel_start_bus_after_clock_stop(struct sdw_intel *sdw) struct sdw_cdns *cdns = &sdw->cdns; int ret; - ret = sdw_cdns_enable_interrupt(cdns, true); + ret = sdw_cdns_clock_restart(cdns, false); if (ret < 0) { - dev_err(dev, "%s: cannot enable interrupts: %d\n", __func__, ret); + dev_err(dev, "%s: unable to restart clock: %d\n", __func__, ret); return ret; } - ret = sdw_cdns_clock_restart(cdns, false); + ret = sdw_cdns_enable_interrupt(cdns, true); if (ret < 0) { - dev_err(dev, "%s: unable to restart clock: %d\n", __func__, ret); - sdw_cdns_enable_interrupt(cdns, false); + dev_err(dev, "%s: cannot enable interrupts: %d\n", __func__, ret); return ret; } From f6df873bccc5a55cf061d9baf689eef79c85d4ba Mon Sep 17 00:00:00 2001 From: Pierre-Louis Bossart Date: Mon, 6 Mar 2023 13:46:15 -0600 Subject: [PATCH 2/4] soundwire: intel/cadence: update hardware reset sequence Combining hardware reset with the multi-link mode leads to a shortened hardware reset pattern observed on the bus. The updated hardware programming sequence is to first enable the clock with the sync_arm/sync_go pattern, and only in a second step to issue the hardware reset sequence. Since there is no longer a dependency between sync_arm/sync_go and hw_reset, the behavior of sdw_cdns_exit_reset() is changed to wait for the self-clearing CONFIG_UPDATE to go back to zero, Link: https://github.com/thesofproject/linux/issues/4170 Signed-off-by: Pierre-Louis Bossart --- drivers/soundwire/cadence_master.c | 31 ++++++++++++++++++------ drivers/soundwire/cadence_master.h | 3 +++ drivers/soundwire/intel_bus_common.c | 36 ++++++++++++++++++++-------- 3 files changed, 53 insertions(+), 17 deletions(-) diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c index 3dc49942dc0e6b..b7b03ad3612f8d 100644 --- a/drivers/soundwire/cadence_master.c +++ b/drivers/soundwire/cadence_master.c @@ -283,6 +283,29 @@ static int cdns_config_update(struct sdw_cdns *cdns) return ret; } +/** + * sdw_cdns_config_update() - Update configurations + * @cdns: Cadence instance + */ +void sdw_cdns_config_update(struct sdw_cdns *cdns) +{ + /* commit changes */ + cdns_writel(cdns, CDNS_MCP_CONFIG_UPDATE, CDNS_MCP_CONFIG_UPDATE_BIT); +} +EXPORT_SYMBOL(sdw_cdns_config_update); + +/** + * sdw_cdns_config_update_set_wait() - wait until configuration update bit is self-cleared + * @cdns: Cadence instance + */ +int sdw_cdns_config_update_set_wait(struct sdw_cdns *cdns) +{ + /* the hardware recommendation is to wait at least 300us */ + return cdns_set_wait(cdns, CDNS_MCP_CONFIG_UPDATE, + CDNS_MCP_CONFIG_UPDATE_BIT, 0); +} +EXPORT_SYMBOL(sdw_cdns_config_update_set_wait); + /* * debugfs */ @@ -1116,13 +1139,7 @@ int sdw_cdns_exit_reset(struct sdw_cdns *cdns) CDNS_MCP_CONTROL_HW_RST); /* commit changes */ - cdns_updatel(cdns, CDNS_MCP_CONFIG_UPDATE, - CDNS_MCP_CONFIG_UPDATE_BIT, - CDNS_MCP_CONFIG_UPDATE_BIT); - - /* don't wait here */ - return 0; - + return cdns_config_update(cdns); } EXPORT_SYMBOL(sdw_cdns_exit_reset); diff --git a/drivers/soundwire/cadence_master.h b/drivers/soundwire/cadence_master.h index b0f0bf90640bf9..46d77579804298 100644 --- a/drivers/soundwire/cadence_master.h +++ b/drivers/soundwire/cadence_master.h @@ -201,4 +201,7 @@ int cdns_set_sdw_stream(struct snd_soc_dai *dai, void sdw_cdns_check_self_clearing_bits(struct sdw_cdns *cdns, const char *string, bool initial_delay, int reset_iterations); +void sdw_cdns_config_update(struct sdw_cdns *cdns); +int sdw_cdns_config_update_set_wait(struct sdw_cdns *cdns); + #endif /* __SDW_CADENCE_H */ diff --git a/drivers/soundwire/intel_bus_common.c b/drivers/soundwire/intel_bus_common.c index 901d4f5736c18e..be0c93106fc89e 100644 --- a/drivers/soundwire/intel_bus_common.c +++ b/drivers/soundwire/intel_bus_common.c @@ -29,11 +29,7 @@ int intel_start_bus(struct sdw_intel *sdw) return ret; } - ret = sdw_cdns_exit_reset(cdns); - if (ret < 0) { - dev_err(dev, "%s: unable to exit bus reset sequence: %d\n", __func__, ret); - return ret; - } + sdw_cdns_config_update(cdns); if (bus->multi_link) { ret = sdw_intel_sync_go(sdw); @@ -43,6 +39,18 @@ int intel_start_bus(struct sdw_intel *sdw) } } + ret = sdw_cdns_config_update_set_wait(cdns); + if (ret < 0) { + dev_err(dev, "%s: CONFIG_UPDATE BIT still set\n", __func__); + return ret; + } + + ret = sdw_cdns_exit_reset(cdns); + if (ret < 0) { + dev_err(dev, "%s: unable to exit bus reset sequence: %d\n", __func__, ret); + return ret; + } + ret = sdw_cdns_enable_interrupt(cdns, true); if (ret < 0) { dev_err(dev, "%s: cannot enable interrupts: %d\n", __func__, ret); @@ -112,11 +120,7 @@ int intel_start_bus_after_reset(struct sdw_intel *sdw) } if (!clock_stop0) { - ret = sdw_cdns_exit_reset(cdns); - if (ret < 0) { - dev_err(dev, "unable to exit bus reset sequence during resume\n"); - return ret; - } + sdw_cdns_config_update(cdns); if (bus->multi_link) { ret = sdw_intel_sync_go(sdw); @@ -126,6 +130,18 @@ int intel_start_bus_after_reset(struct sdw_intel *sdw) } } + ret = sdw_cdns_config_update_set_wait(cdns); + if (ret < 0) { + dev_err(dev, "%s: CONFIG_UPDATE BIT still set\n", __func__); + return ret; + } + + ret = sdw_cdns_exit_reset(cdns); + if (ret < 0) { + dev_err(dev, "unable to exit bus reset sequence during resume\n"); + return ret; + } + ret = sdw_cdns_enable_interrupt(cdns, true); if (ret < 0) { dev_err(dev, "cannot enable interrupts during resume\n"); From b46b3d368121c4fbb6314407a514d993386eefc8 Mon Sep 17 00:00:00 2001 From: Pierre-Louis Bossart Date: Mon, 10 Apr 2023 11:08:52 -0500 Subject: [PATCH 3/4] soundwire: cadence: revisit parity injection We want to wait for the CONFIG_UPDATE bit to clear before doing something else. Signed-off-by: Pierre-Louis Bossart --- drivers/soundwire/cadence_master.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c index b7b03ad3612f8d..eb1b87ad1681c2 100644 --- a/drivers/soundwire/cadence_master.c +++ b/drivers/soundwire/cadence_master.c @@ -456,9 +456,9 @@ static int cdns_parity_error_injection(void *data, u64 value) CDNS_IP_MCP_CMDCTRL_INSERT_PARITY_ERR); /* commit changes */ - cdns_updatel(cdns, CDNS_MCP_CONFIG_UPDATE, - CDNS_MCP_CONFIG_UPDATE_BIT, - CDNS_MCP_CONFIG_UPDATE_BIT); + ret = cdns_clear_bit(cdns, CDNS_MCP_CONFIG_UPDATE, CDNS_MCP_CONFIG_UPDATE_BIT); + if (ret < 0) + goto unlock; /* do a broadcast dummy read to avoid bus clashes */ ret = sdw_bread_no_pm_unlocked(&cdns->bus, 0xf, SDW_SCP_DEVID_0); @@ -470,16 +470,17 @@ static int cdns_parity_error_injection(void *data, u64 value) 0); /* commit changes */ - cdns_updatel(cdns, CDNS_MCP_CONFIG_UPDATE, - CDNS_MCP_CONFIG_UPDATE_BIT, - CDNS_MCP_CONFIG_UPDATE_BIT); - - /* Continue bus operation with parity error injection disabled */ - mutex_unlock(&bus->bus_lock); + ret = cdns_clear_bit(cdns, CDNS_MCP_CONFIG_UPDATE, CDNS_MCP_CONFIG_UPDATE_BIT); + if (ret < 0) + goto unlock; /* Userspace changed the hardware state behind the kernel's back */ add_taint(TAINT_USER, LOCKDEP_STILL_OK); +unlock: + /* Continue bus operation with parity error injection disabled */ + mutex_unlock(&bus->bus_lock); + /* * allow Master device to enter pm_runtime suspend. This may * also result in Slave devices suspending. From 0e1e69ee729b01f5015e5c75cfd7d15d10ed5ae8 Mon Sep 17 00:00:00 2001 From: Pierre-Louis Bossart Date: Mon, 10 Apr 2023 14:07:52 -0500 Subject: [PATCH 4/4] soundwire: intel_bus_common: update error log We use __func__ in all calls of sdw_cdns_check_self_clearing_bits(), except in one case. Likely an editing miss when the code was refactored. Signed-off-by: Pierre-Louis Bossart --- drivers/soundwire/intel_bus_common.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/soundwire/intel_bus_common.c b/drivers/soundwire/intel_bus_common.c index be0c93106fc89e..e5ac3cc7cb79b1 100644 --- a/drivers/soundwire/intel_bus_common.c +++ b/drivers/soundwire/intel_bus_common.c @@ -182,8 +182,7 @@ int intel_start_bus_after_clock_stop(struct sdw_intel *sdw) return ret; } - sdw_cdns_check_self_clearing_bits(cdns, "intel_resume_runtime no_quirks", - true, INTEL_MASTER_RESET_ITERATIONS); + sdw_cdns_check_self_clearing_bits(cdns, __func__, true, INTEL_MASTER_RESET_ITERATIONS); return 0; }