1 files changed, 240 insertions, 42 deletions

diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c
index 9bec270d0fa4..ecd357d1c63d 100644
--- a/drivers/soundwire/cadence_master.c
+++ b/drivers/soundwire/cadence_master.c
@@ -183,7 +183,6 @@ MODULE_PARM_DESC(cdns_mcp_int_mask, "Cadence MCP IntMask");
 #define CDNS_PDI_CONFIG_PORT			GENMASK(4, 0)
 
 /* Driver defaults */
-#define CDNS_DEFAULT_SSP_INTERVAL		0x18
 #define CDNS_TX_TIMEOUT				2000
 
 #define CDNS_SCP_RX_FIFOLEVEL			0x2
@@ -211,34 +210,45 @@ static inline void cdns_updatel(struct sdw_cdns *cdns,
 	cdns_writel(cdns, offset, tmp);
 }
 
-static int cdns_clear_bit(struct sdw_cdns *cdns, int offset, u32 value)
+static int cdns_set_wait(struct sdw_cdns *cdns, int offset, u32 mask, u32 value)
 {
 	int timeout = 10;
 	u32 reg_read;
 
-	writel(value, cdns->registers + offset);
-
-	/* Wait for bit to be self cleared */
+	/* Wait for bit to be set */
 	do {
 		reg_read = readl(cdns->registers + offset);
-		if ((reg_read & value) == 0)
+		if ((reg_read & mask) == value)
 			return 0;
 
 		timeout--;
-		udelay(50);
+		usleep_range(50, 100);
 	} while (timeout != 0);
 
-	return -EAGAIN;
+	return -ETIMEDOUT;
+}
+
+static int cdns_clear_bit(struct sdw_cdns *cdns, int offset, u32 value)
+{
+	writel(value, cdns->registers + offset);
+
+	/* Wait for bit to be self cleared */
+	return cdns_set_wait(cdns, offset, value, 0);
 }
 
 /*
  * 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)
+static int cdns_config_update(struct sdw_cdns *cdns)
 {
 	int ret;
 
+	if (sdw_cdns_is_clock_stop(cdns)) {
+		dev_err(cdns->dev, "Cannot program MCP_CONFIG_UPDATE in ClockStopMode\n");
+		return -EINVAL;
+	}
+
 	ret = cdns_clear_bit(cdns, CDNS_MCP_CONFIG_UPDATE,
 			     CDNS_MCP_CONFIG_UPDATE_BIT);
 	if (ret < 0)
@@ -832,17 +842,36 @@ int sdw_cdns_exit_reset(struct sdw_cdns *cdns)
 		     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);
+	cdns_updatel(cdns, CDNS_MCP_CONFIG_UPDATE,
+		     CDNS_MCP_CONFIG_UPDATE_BIT,
+		     CDNS_MCP_CONFIG_UPDATE_BIT);
+
+	/* don't wait here */
+	return 0;
+
 }
 EXPORT_SYMBOL(sdw_cdns_exit_reset);
 
 /**
+ * sdw_cdns_enable_slave_interrupt() - Enable SDW slave interrupts
+ * @cdns: Cadence instance
+ * @state: boolean for true/false
+ */
+static void cdns_enable_slave_interrupts(struct sdw_cdns *cdns, bool state)
+{
+	u32 mask;
+
+	mask = cdns_readl(cdns, CDNS_MCP_INTMASK);
+	if (state)
+		mask |= CDNS_MCP_INT_SLAVE_MASK;
+	else
+		mask &= ~CDNS_MCP_INT_SLAVE_MASK;
+
+	cdns_writel(cdns, CDNS_MCP_INTMASK, mask);
+}
+
+/**
  * sdw_cdns_enable_interrupt() - Enable SDW interrupts
  * @cdns: Cadence instance
  * @state: True if we are trying to enable interrupt.
@@ -1014,26 +1043,13 @@ static u32 cdns_set_initial_frame_shape(int n_rows, int n_cols)
 	return val;
 }
 
-/**
- * sdw_cdns_init() - Cadence initialization
- * @cdns: Cadence instance
- */
-int sdw_cdns_init(struct sdw_cdns *cdns, bool clock_stop_exit)
+static void 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 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 */
 	divider	= (prop->mclk_freq / prop->max_clk_freq) - 1;
@@ -1052,8 +1068,23 @@ int sdw_cdns_init(struct sdw_cdns *cdns, bool clock_stop_exit)
 	cdns_writel(cdns, CDNS_MCP_FRAME_SHAPE_INIT, val);
 
 	/* Set SSP interval to default value */
-	cdns_writel(cdns, CDNS_MCP_SSP_CTRL0, CDNS_DEFAULT_SSP_INTERVAL);
-	cdns_writel(cdns, CDNS_MCP_SSP_CTRL1, CDNS_DEFAULT_SSP_INTERVAL);
+	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);
+}
+
+/**
+ * sdw_cdns_init() - Cadence initialization
+ * @cdns: Cadence instance
+ */
+int sdw_cdns_init(struct sdw_cdns *cdns)
+{
+	u32 val;
+
+	cdns_init_clock_ctrl(cdns);
+
+	/* reset msg_count to default value of FIFOLEVEL */
+	cdns->msg_count = cdns_readl(cdns, CDNS_MCP_FIFOLEVEL);
 
 	/* flush command FIFOs */
 	cdns_updatel(cdns, CDNS_MCP_CONTROL, CDNS_MCP_CONTROL_CMD_RST,
@@ -1066,25 +1097,31 @@ int sdw_cdns_init(struct sdw_cdns *cdns, bool clock_stop_exit)
 	/* Configure mcp config */
 	val = cdns_readl(cdns, CDNS_MCP_CONFIG);
 
-	/* Set Max cmd retry to 15 */
-	val |= CDNS_MCP_CONFIG_MCMD_RETRY;
+	/* enable bus operations with clock and data */
+	val &= ~CDNS_MCP_CONFIG_OP;
+	val |= CDNS_MCP_CONFIG_OP_NORMAL;
 
-	/* Set frame delay between PREQ and ping frame to 15 frames */
-	val |= 0xF << SDW_REG_SHIFT(CDNS_MCP_CONFIG_MPREQ_DELAY);
+	/* Set cmd mode for Tx and Rx cmds */
+	val &= ~CDNS_MCP_CONFIG_CMD;
+
+	/* Disable sniffer mode */
+	val &= ~CDNS_MCP_CONFIG_SNIFFER;
 
 	/* Disable auto bus release */
 	val &= ~CDNS_MCP_CONFIG_BUS_REL;
 
-	/* Disable sniffer mode */
-	val &= ~CDNS_MCP_CONFIG_SNIFFER;
+	if (cdns->bus.multi_link)
+		/* Set Multi-master mode to take gsync into account */
+		val |= CDNS_MCP_CONFIG_MMASTER;
 
-	/* Set cmd mode for Tx and Rx cmds */
-	val &= ~CDNS_MCP_CONFIG_CMD;
+	/* leave frame delay to hardware default of 0x1F */
+
+	/* leave command retry to hardware default of 0 */
 
 	cdns_writel(cdns, CDNS_MCP_CONFIG, val);
 
-	/* commit changes */
-	return cdns_update_config(cdns);
+	/* changes will be committed later */
+	return 0;
 }
 EXPORT_SYMBOL(sdw_cdns_init);
 
@@ -1218,6 +1255,166 @@ static const struct sdw_master_port_ops cdns_port_ops = {
 };
 
 /**
+ * sdw_cdns_is_clock_stop: Check clock status
+ *
+ * @cdns: Cadence instance
+ */
+bool sdw_cdns_is_clock_stop(struct sdw_cdns *cdns)
+{
+	return !!(cdns_readl(cdns, CDNS_MCP_STAT) & CDNS_MCP_STAT_CLK_STOP);
+}
+EXPORT_SYMBOL(sdw_cdns_is_clock_stop);
+
+/**
+ * sdw_cdns_clock_stop: Cadence clock stop configuration routine
+ *
+ * @cdns: Cadence instance
+ * @block_wake: prevent wakes if required by the platform
+ */
+int sdw_cdns_clock_stop(struct sdw_cdns *cdns, bool block_wake)
+{
+	bool slave_present = false;
+	struct sdw_slave *slave;
+	int ret;
+
+	/* Check suspend status */
+	if (sdw_cdns_is_clock_stop(cdns)) {
+		dev_dbg(cdns->dev, "Clock is already stopped\n");
+		return 0;
+	}
+
+	/*
+	 * Before entering clock stop we mask the Slave
+	 * interrupts. This helps avoid having to deal with e.g. a
+	 * Slave becoming UNATTACHED while the clock is being stopped
+	 */
+	cdns_enable_slave_interrupts(cdns, false);
+
+	/*
+	 * For specific platforms, it is required to be able to put
+	 * master into a state in which it ignores wake-up trials
+	 * in clock stop state
+	 */
+	if (block_wake)
+		cdns_updatel(cdns, CDNS_MCP_CONTROL,
+			     CDNS_MCP_CONTROL_BLOCK_WAKEUP,
+			     CDNS_MCP_CONTROL_BLOCK_WAKEUP);
+
+	list_for_each_entry(slave, &cdns->bus.slaves, node) {
+		if (slave->status == SDW_SLAVE_ATTACHED ||
+		    slave->status == SDW_SLAVE_ALERT) {
+			slave_present = true;
+			break;
+		}
+	}
+
+	/*
+	 * This CMD_ACCEPT should be used when there are no devices
+	 * attached on the link when entering clock stop mode. If this is
+	 * not set and there is a broadcast write then the command ignored
+	 * will be treated as a failure
+	 */
+	if (!slave_present)
+		cdns_updatel(cdns, CDNS_MCP_CONTROL,
+			     CDNS_MCP_CONTROL_CMD_ACCEPT,
+			     CDNS_MCP_CONTROL_CMD_ACCEPT);
+	else
+		cdns_updatel(cdns, CDNS_MCP_CONTROL,
+			     CDNS_MCP_CONTROL_CMD_ACCEPT, 0);
+
+	/* commit changes */
+	ret = cdns_config_update(cdns);
+	if (ret < 0) {
+		dev_err(cdns->dev, "%s: config_update failed\n", __func__);
+		return ret;
+	}
+
+	/* Prepare slaves for clock stop */
+	ret = sdw_bus_prep_clk_stop(&cdns->bus);
+	if (ret < 0) {
+		dev_err(cdns->dev, "prepare clock stop failed %d", ret);
+		return ret;
+	}
+
+	/*
+	 * Enter clock stop mode and only report errors if there are
+	 * Slave devices present (ALERT or ATTACHED)
+	 */
+	ret = sdw_bus_clk_stop(&cdns->bus);
+	if (ret < 0 && slave_present && ret != -ENODATA) {
+		dev_err(cdns->dev, "bus clock stop failed %d", ret);
+		return ret;
+	}
+
+	ret = cdns_set_wait(cdns, CDNS_MCP_STAT,
+			    CDNS_MCP_STAT_CLK_STOP,
+			    CDNS_MCP_STAT_CLK_STOP);
+	if (ret < 0)
+		dev_err(cdns->dev, "Clock stop failed %d\n", ret);
+
+	return ret;
+}
+EXPORT_SYMBOL(sdw_cdns_clock_stop);
+
+/**
+ * sdw_cdns_clock_restart: Cadence PM clock restart configuration routine
+ *
+ * @cdns: Cadence instance
+ * @bus_reset: context may be lost while in low power modes and the bus
+ * may require a Severe Reset and re-enumeration after a wake.
+ */
+int sdw_cdns_clock_restart(struct sdw_cdns *cdns, bool bus_reset)
+{
+	int ret;
+
+	/* unmask Slave interrupts that were masked when stopping the clock */
+	cdns_enable_slave_interrupts(cdns, true);
+
+	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;
+	}
+
+	ret = cdns_set_wait(cdns, CDNS_MCP_STAT, CDNS_MCP_STAT_CLK_STOP, 0);
+	if (ret < 0) {
+		dev_err(cdns->dev, "clock stop exit failed %d\n", ret);
+		return ret;
+	}
+
+	cdns_updatel(cdns, CDNS_MCP_CONTROL,
+		     CDNS_MCP_CONTROL_BLOCK_WAKEUP, 0);
+
+	/*
+	 * clear CMD_ACCEPT so that the command ignored
+	 * will be treated as a failure during a broadcast write
+	 */
+	cdns_updatel(cdns, CDNS_MCP_CONTROL, CDNS_MCP_CONTROL_CMD_ACCEPT, 0);
+
+	if (!bus_reset) {
+
+		/* enable bus operations with clock and data */
+		cdns_updatel(cdns, CDNS_MCP_CONFIG,
+			     CDNS_MCP_CONFIG_OP,
+			     CDNS_MCP_CONFIG_OP_NORMAL);
+
+		ret = cdns_config_update(cdns);
+		if (ret < 0) {
+			dev_err(cdns->dev, "%s: config_update failed\n", __func__);
+			return ret;
+		}
+
+		ret = sdw_bus_exit_clk_stop(&cdns->bus);
+		if (ret < 0)
+			dev_err(cdns->dev, "bus failed to exit clock stop %d\n", ret);
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL(sdw_cdns_clock_restart);
+
+/**
  * sdw_cdns_probe() - Cadence probe routine
  * @cdns: Cadence instance
  */
@@ -1306,6 +1503,7 @@ void sdw_cdns_config_stream(struct sdw_cdns *cdns,
 	cdns_updatel(cdns, offset, CDNS_PORTCTRL_DIRN, val);
 
 	val = pdi->num;
+	val |= CDNS_PDI_CONFIG_SOFT_RESET;
 	val |= ((1 << ch) - 1) << SDW_REG_SHIFT(CDNS_PDI_CONFIG_CHANNEL);
 	cdns_writel(cdns, CDNS_PDI_CONFIG(pdi->num), val);
 }