3 files changed, 65 insertions, 0 deletions

diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c
index 9a9b6110e763..a9bd56f0d534 100644
--- a/drivers/soundwire/cadence_master.c
+++ b/drivers/soundwire/cadence_master.c
@@ -935,6 +935,49 @@ static void cdns_update_slave_status_work(struct work_struct *work)
 
 }
 
+/* paranoia check to make sure self-cleared bits are indeed cleared */
+void sdw_cdns_check_self_clearing_bits(struct sdw_cdns *cdns, const char *string,
+				       bool initial_delay, int reset_iterations)
+{
+	u32 mcp_control;
+	u32 mcp_config_update;
+	int i;
+
+	if (initial_delay)
+		usleep_range(1000, 1500);
+
+	mcp_control = cdns_readl(cdns, CDNS_MCP_CONTROL);
+
+	/* the following bits should be cleared immediately */
+	if (mcp_control & CDNS_MCP_CONTROL_CMD_RST)
+		dev_err(cdns->dev, "%s failed: MCP_CONTROL_CMD_RST is not cleared\n", string);
+	if (mcp_control & CDNS_MCP_CONTROL_SOFT_RST)
+		dev_err(cdns->dev, "%s failed: MCP_CONTROL_SOFT_RST is not cleared\n", string);
+	if (mcp_control & CDNS_MCP_CONTROL_SW_RST)
+		dev_err(cdns->dev, "%s failed: MCP_CONTROL_SW_RST is not cleared\n", string);
+	if (mcp_control & CDNS_MCP_CONTROL_CLK_STOP_CLR)
+		dev_err(cdns->dev, "%s failed: MCP_CONTROL_CLK_STOP_CLR is not cleared\n", string);
+	mcp_config_update = cdns_readl(cdns, CDNS_MCP_CONFIG_UPDATE);
+	if (mcp_config_update & CDNS_MCP_CONFIG_UPDATE_BIT)
+		dev_err(cdns->dev, "%s failed: MCP_CONFIG_UPDATE_BIT is not cleared\n", string);
+
+	i = 0;
+	while (mcp_control & CDNS_MCP_CONTROL_HW_RST) {
+		if (i == reset_iterations) {
+			dev_err(cdns->dev, "%s failed: MCP_CONTROL_HW_RST is not cleared\n", string);
+			break;
+		}
+
+		dev_dbg(cdns->dev, "%s: MCP_CONTROL_HW_RST is not cleared at iteration %d\n", string, i);
+		i++;
+
+		usleep_range(1000, 1500);
+		mcp_control = cdns_readl(cdns, CDNS_MCP_CONTROL);
+	}
+
+}
+EXPORT_SYMBOL(sdw_cdns_check_self_clearing_bits);
+
 /*
  * init routines
  */
@@ -1212,6 +1255,8 @@ int sdw_cdns_init(struct sdw_cdns *cdns)
 
 	cdns_init_clock_ctrl(cdns);
 
+	sdw_cdns_check_self_clearing_bits(cdns, __func__, false, 0);
+
 	/* reset msg_count to default value of FIFOLEVEL */
 	cdns->msg_count = cdns_readl(cdns, CDNS_MCP_FIFOLEVEL);
 
@@ -1396,6 +1441,8 @@ int sdw_cdns_clock_stop(struct sdw_cdns *cdns, bool block_wake)
 	struct sdw_slave *slave;
 	int ret;
 
+	sdw_cdns_check_self_clearing_bits(cdns, __func__, false, 0);
+
 	/* Check suspend status */
 	if (sdw_cdns_is_clock_stop(cdns)) {
 		dev_dbg(cdns->dev, "Clock is already stopped\n");
diff --git a/drivers/soundwire/cadence_master.h b/drivers/soundwire/cadence_master.h
index 0e7f8b35bb21..b54c161a837f 100644
--- a/drivers/soundwire/cadence_master.h
+++ b/drivers/soundwire/cadence_master.h
@@ -184,4 +184,8 @@ int cdns_bus_conf(struct sdw_bus *bus, struct sdw_bus_params *params);
 
 int cdns_set_sdw_stream(struct snd_soc_dai *dai,
 			void *stream, bool pcm, int direction);
+
+void sdw_cdns_check_self_clearing_bits(struct sdw_cdns *cdns, const char *string,
+				       bool initial_delay, int reset_iterations);
+
 #endif /* __SDW_CADENCE_H */
diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c
index c11e3d8cd308..9794bc222fb5 100644
--- a/drivers/soundwire/intel.c
+++ b/drivers/soundwire/intel.c
@@ -23,6 +23,7 @@
 #include "intel.h"
 
 #define INTEL_MASTER_SUSPEND_DELAY_MS	3000
+#define INTEL_MASTER_RESET_ITERATIONS	10
 
 /*
  * debug/config flags for the Intel SoundWire Master.
@@ -1467,6 +1468,8 @@ int intel_link_startup(struct auxiliary_device *auxdev)
 			goto err_interrupt;
 		}
 	}
+	sdw_cdns_check_self_clearing_bits(cdns, __func__,
+					  true, INTEL_MASTER_RESET_ITERATIONS);
 
 	/* Register DAIs */
 	ret = intel_register_dai(sdw);
@@ -1783,6 +1786,8 @@ static int __maybe_unused intel_resume(struct device *dev)
 			return ret;
 		}
 	}
+	sdw_cdns_check_self_clearing_bits(cdns, __func__,
+					  true, INTEL_MASTER_RESET_ITERATIONS);
 
 	/*
 	 * after system resume, the pm_runtime suspend() may kick in
@@ -1867,6 +1872,9 @@ static int __maybe_unused intel_resume_runtime(struct device *dev)
 				return ret;
 			}
 		}
+		sdw_cdns_check_self_clearing_bits(cdns, "intel_resume_runtime TEARDOWN",
+						  true, INTEL_MASTER_RESET_ITERATIONS);
+
 	} else if (clock_stop_quirks & SDW_INTEL_CLK_STOP_BUS_RESET) {
 		ret = intel_init(sdw);
 		if (ret) {
@@ -1940,6 +1948,9 @@ static int __maybe_unused intel_resume_runtime(struct device *dev)
 				}
 			}
 		}
+		sdw_cdns_check_self_clearing_bits(cdns, "intel_resume_runtime BUS_RESET",
+						  true, INTEL_MASTER_RESET_ITERATIONS);
+
 	} else if (!clock_stop_quirks) {
 
 		clock_stop0 = sdw_cdns_is_clock_stop(&sdw->cdns);
@@ -1963,6 +1974,9 @@ static int __maybe_unused intel_resume_runtime(struct device *dev)
 			dev_err(dev, "unable to resume master during resume\n");
 			return ret;
 		}
+
+		sdw_cdns_check_self_clearing_bits(cdns, "intel_resume_runtime no_quirks",
+						  true, INTEL_MASTER_RESET_ITERATIONS);
 	} else {
 		dev_err(dev, "%s clock_stop_quirks %x unsupported\n",
 			__func__, clock_stop_quirks);