diff mbox series

[2/4] i3c: master: cdns: add support for mastership request to Cadence I3C master driver.

Message ID 20190218130846.19939-3-pgaj@cadence.com (mailing list archive)
State Superseded
Headers show
Series Add the I3C mastership request | expand

Commit Message

Przemysław Gaj Feb. 18, 2019, 1:08 p.m. UTC
This patch adds support for mastership request to Cadence I3C master driver.

Mastership is requested automatically after secondary master receives
mastership ENEC event. This allows secondary masters to initialize their bus.

Signed-off-by: Przemyslaw Gaj <pgaj@cadence.com>

Main changes between v2 and v3:
- Add mastership type
- Add postponed master registration
- Add update device definition on bus initialization time
- Removed redundant mastership work structs
- Reworked IBI slot lookup
- Reworked Mastership event enabling/disabling

Changes in v2:
- Add work structs for mastership purpose
- Add missing mastership disable feature
---
 drivers/i3c/master/i3c-master-cdns.c | 493 +++++++++++++++++++++++++++++++----
 1 file changed, 442 insertions(+), 51 deletions(-)
diff mbox series

Patch

diff --git a/drivers/i3c/master/i3c-master-cdns.c b/drivers/i3c/master/i3c-master-cdns.c
index 8889a4f..de4c4ad 100644
--- a/drivers/i3c/master/i3c-master-cdns.c
+++ b/drivers/i3c/master/i3c-master-cdns.c
@@ -157,6 +157,7 @@ 
 #define SLV_IMR				0x48
 #define SLV_ICR				0x4c
 #define SLV_ISR				0x50
+#define SLV_INT_DEFSLVS			BIT(21)
 #define SLV_INT_TM			BIT(20)
 #define SLV_INT_ERROR			BIT(19)
 #define SLV_INT_EVENT_UP		BIT(18)
@@ -388,8 +389,19 @@  struct cdns_i3c_xfer {
 	struct cdns_i3c_cmd cmds[0];
 };
 
+enum cdns_i3c_mr {
+	REQUEST,
+	HANDOFF,
+	TAKEOVER
+};
+
 struct cdns_i3c_master {
 	struct work_struct hj_work;
+	struct {
+		struct work_struct work;
+		enum cdns_i3c_mr mr_type;
+		u32 ibir;
+	} mastership;
 	struct i3c_master_controller base;
 	u32 free_rr_slots;
 	unsigned int maxdevs;
@@ -408,6 +420,8 @@  struct cdns_i3c_master {
 	struct clk *pclk;
 	struct cdns_i3c_master_caps caps;
 	unsigned long i3c_scl_lim;
+	struct device *parent;
+	struct workqueue_struct *wq;
 };
 
 static inline struct cdns_i3c_master *
@@ -663,6 +677,88 @@  static void cdns_i3c_master_unqueue_xfer(struct cdns_i3c_master *master,
 	spin_unlock_irqrestore(&master->xferqueue.lock, flags);
 }
 
+static void
+cdns_i3c_master_i3c_dev_rr_to_info(struct cdns_i3c_master *master,
+				   unsigned int slot,
+				   struct i3c_device_info *info)
+{
+	u32 rr;
+
+	memset(info, 0, sizeof(*info));
+	rr = readl(master->regs + DEV_ID_RR0(slot));
+	info->dyn_addr = DEV_ID_RR0_GET_DEV_ADDR(rr);
+	rr = readl(master->regs + DEV_ID_RR2(slot));
+	info->dcr = rr;
+	info->bcr = rr >> 8;
+	info->pid = rr >> 16;
+	info->pid |= (u64)readl(master->regs + DEV_ID_RR1(slot)) << 16;
+}
+
+static void
+cdns_i3c_master_i2c_dev_rr_to_info(struct cdns_i3c_master *master,
+				   unsigned int slot,
+				   u16 *addr, u8 *lvr)
+{
+	u32 rr;
+
+	rr = readl(master->regs + DEV_ID_RR0(slot));
+	*addr = DEV_ID_RR0_GET_DEV_ADDR(rr);
+	rr = readl(master->regs + DEV_ID_RR2(slot));
+	*lvr = rr;
+}
+
+static
+int cdns_i3c_sec_master_request_mastership(struct i3c_master_controller *m)
+{
+	struct cdns_i3c_master *master = to_cdns_i3c_master(m);
+	u32 status;
+	int ret;
+
+	status = readl(master->regs + MST_STATUS0);
+	if (WARN_ON(status & MST_STATUS0_MASTER_MODE))
+		return -EEXIST;
+
+	status = readl(master->regs + SLV_STATUS1);
+	if (status & SLV_STATUS1_MR_DIS)
+		return -EACCES;
+
+	writel(SLV_INT_MR_DONE, master->regs + SLV_IER);
+	writel(readl(master->regs + CTRL) | CTRL_MST_INIT | CTRL_MST_ACK,
+	       master->regs + CTRL);
+
+	ret = readl_poll_timeout(master->regs + MST_STATUS0, status,
+				 status & MST_STATUS0_MASTER_MODE, 100,
+				 100000);
+	return ret;
+}
+
+static void cdns_i3c_master_update_devs(struct i3c_master_controller *m)
+{
+	struct cdns_i3c_master *master = to_cdns_i3c_master(m);
+	u32 val, newdevs;
+	u16 addr;
+	u8 lvr;
+	int slot;
+	struct i3c_device_info i3c_info;
+
+	newdevs = readl(master->regs + DEVS_CTRL) & DEVS_CTRL_DEVS_ACTIVE_MASK;
+	for (slot = 1; slot <= master->maxdevs; slot++) {
+		val = readl(master->regs + DEV_ID_RR0(slot));
+
+		if ((newdevs & BIT(slot)) && (val & DEV_ID_RR0_IS_I3C)) {
+			cdns_i3c_master_i3c_dev_rr_to_info(master, slot,
+							   &i3c_info);
+
+			i3c_master_add_i3c_dev_locked(m, i3c_info.dyn_addr);
+		} else if ((newdevs & BIT(slot)) &&
+			   !(val & DEV_ID_RR0_IS_I3C)) {
+			cdns_i3c_master_i2c_dev_rr_to_info(master, slot,
+							   &addr, &lvr);
+			i3c_master_add_i2c_dev(m, addr, lvr);
+		}
+	}
+}
+
 static enum i3c_error_code cdns_i3c_cmd_get_err(struct cdns_i3c_cmd *cmd)
 {
 	switch (cmd->error) {
@@ -1044,22 +1140,6 @@  static void cdns_i3c_master_bus_cleanup(struct i3c_master_controller *m)
 	cdns_i3c_master_disable(master);
 }
 
-static void cdns_i3c_master_dev_rr_to_info(struct cdns_i3c_master *master,
-					   unsigned int slot,
-					   struct i3c_device_info *info)
-{
-	u32 rr;
-
-	memset(info, 0, sizeof(*info));
-	rr = readl(master->regs + DEV_ID_RR0(slot));
-	info->dyn_addr = DEV_ID_RR0_GET_DEV_ADDR(rr);
-	rr = readl(master->regs + DEV_ID_RR2(slot));
-	info->dcr = rr;
-	info->bcr = rr >> 8;
-	info->pid = rr >> 16;
-	info->pid |= (u64)readl(master->regs + DEV_ID_RR1(slot)) << 16;
-}
-
 static void cdns_i3c_master_upd_i3c_scl_lim(struct cdns_i3c_master *master)
 {
 	struct i3c_master_controller *m = &master->base;
@@ -1187,10 +1267,6 @@  static int cdns_i3c_master_do_daa(struct i3c_master_controller *m)
 
 	cdns_i3c_master_upd_i3c_scl_lim(master);
 
-	/* Unmask Hot-Join and Mastership request interrupts. */
-	i3c_master_enec_locked(m, I3C_BROADCAST_ADDR,
-			       I3C_CCC_EVENT_HJ | I3C_CCC_EVENT_MR);
-
 	return 0;
 }
 
@@ -1254,15 +1330,17 @@  static int cdns_i3c_master_bus_init(struct i3c_master_controller *m)
 	prescl1 = PRESCL_CTRL1_OD_LOW(ncycles);
 	writel(prescl1, master->regs + PRESCL_CTRL1);
 
-	/* Get an address for the master. */
-	ret = i3c_master_get_free_addr(m, 0);
-	if (ret < 0)
-		return ret;
+	if (!m->secondary) {
+		/* Get an address for the master. */
+		ret = i3c_master_get_free_addr(m, 0);
+		if (ret < 0)
+			return ret;
 
-	writel(prepare_rr0_dev_address(ret) | DEV_ID_RR0_IS_I3C,
-	       master->regs + DEV_ID_RR0(0));
+		writel(prepare_rr0_dev_address(ret) | DEV_ID_RR0_IS_I3C,
+		       master->regs + DEV_ID_RR0(0));
+	}
 
-	cdns_i3c_master_dev_rr_to_info(master, 0, &info);
+	cdns_i3c_master_i3c_dev_rr_to_info(master, 0, &info);
 	if (info.bcr & I3C_BCR_HDR_CAP)
 		info.hdr_cap = I3C_CCC_HDR_MODE(I3C_HDR_DDR);
 
@@ -1281,9 +1359,32 @@  static int cdns_i3c_master_bus_init(struct i3c_master_controller *m)
 
 	cdns_i3c_master_enable(master);
 
+	if (m->secondary) {
+		i3c_bus_maintenance_lock(&master->base.bus);
+		cdns_i3c_master_update_devs(&master->base);
+		i3c_bus_maintenance_unlock(&master->base.bus);
+	}
+
 	return 0;
 }
 
+static
+struct i3c_dev_desc *cdns_i3c_get_ibi_device(struct cdns_i3c_master *master,
+					     u32 ibir)
+{
+	struct i3c_dev_desc *dev;
+	u32 id = IBIR_SLVID(ibir);
+
+	if (id >= master->ibi.num_slots || (ibir & IBIR_ERROR))
+		return NULL;
+
+	dev = master->ibi.slots[id];
+	if (!dev)
+		return NULL;
+
+	return dev;
+}
+
 static void cdns_i3c_master_handle_ibi(struct cdns_i3c_master *master,
 				       u32 ibir)
 {
@@ -1361,27 +1462,100 @@  static void cnds_i3c_master_demux_ibis(struct cdns_i3c_master *master)
 
 		case IBIR_TYPE_MR:
 			WARN_ON(IBIR_XFER_BYTES(ibir) || (ibir & IBIR_ERROR));
+			master->mastership.ibir = ibir;
+			master->mastership.mr_type = HANDOFF;
+			queue_work(master->base.wq,
+				   &master->mastership.work);
+			break;
 		default:
 			break;
 		}
 	}
 }
 
+static void cdns_i3c_master_bus_handoff(struct cdns_i3c_master *master)
+{
+	struct i3c_dev_desc *dev;
+
+	dev = cdns_i3c_get_ibi_device(master, master->mastership.ibir);
+
+	writel(MST_INT_MR_DONE, master->regs + MST_ICR);
+
+	master->base.bus.cur_master = dev;
+}
+
+static void cdns_i3c_master_mastership_takeover(struct cdns_i3c_master *master)
+{
+	if (master->base.init_done) {
+		i3c_bus_maintenance_lock(&master->base.bus);
+		cdns_i3c_master_update_devs(&master->base);
+		i3c_bus_maintenance_unlock(&master->base.bus);
+
+		i3c_master_bus_takeover(&master->base);
+	}
+
+	writel(readl(master->regs + CTRL) & ~CTRL_MST_ACK, master->regs + CTRL);
+}
+
+static void cdns_i3c_sec_master_event_up(struct cdns_i3c_master *master)
+{
+	u32 status;
+
+	writel(SLV_INT_EVENT_UP, master->regs + SLV_ICR);
+	status = readl(master->regs + SLV_STATUS1);
+	if (!(status & SLV_STATUS1_MR_DIS) &&
+	    !master->base.this) {
+		master->mastership.mr_type = REQUEST;
+		queue_work(master->wq, &master->mastership.work);
+	}
+}
+
+static void cdns_i3c_sec_mastership_done(struct cdns_i3c_master *master)
+{
+	writel(SLV_INT_MR_DONE, master->regs + SLV_ICR);
+
+	master->base.bus.cur_master = master->base.this;
+
+	if (master->base.this) {
+		master->mastership.mr_type = TAKEOVER;
+		queue_work(master->base.wq, &master->mastership.work);
+	}
+}
+
 static irqreturn_t cdns_i3c_master_interrupt(int irq, void *data)
 {
 	struct cdns_i3c_master *master = data;
 	u32 status;
 
-	status = readl(master->regs + MST_ISR);
-	if (!(status & readl(master->regs + MST_IMR)))
-		return IRQ_NONE;
+	status = readl(master->regs + MST_STATUS0);
+
+	if (!master->base.this ||
+	    master->base.this != master->base.bus.cur_master) {
+		status = readl(master->regs + SLV_ISR);
+
+		if (!(status & readl(master->regs + SLV_IMR)))
+			return IRQ_NONE;
+
+		if (status & SLV_INT_MR_DONE)
+			cdns_i3c_sec_mastership_done(master);
+
+		if (status & SLV_INT_EVENT_UP)
+			cdns_i3c_sec_master_event_up(master);
+	} else {
+		status = readl(master->regs + MST_ISR);
+		if (!(status & readl(master->regs + MST_IMR)))
+			return IRQ_NONE;
+
+		spin_lock(&master->xferqueue.lock);
+		cdns_i3c_master_end_xfer_locked(master, status);
+		spin_unlock(&master->xferqueue.lock);
 
-	spin_lock(&master->xferqueue.lock);
-	cdns_i3c_master_end_xfer_locked(master, status);
-	spin_unlock(&master->xferqueue.lock);
+		if (status & MST_INT_IBIR_THR)
+			cnds_i3c_master_demux_ibis(master);
 
-	if (status & MST_INT_IBIR_THR)
-		cnds_i3c_master_demux_ibis(master);
+		if (status & MST_INT_MR_DONE)
+			cdns_i3c_master_bus_handoff(master);
+	}
 
 	return IRQ_HANDLED;
 }
@@ -1450,30 +1624,54 @@  static int cdns_i3c_master_enable_ibi(struct i3c_dev_desc *dev)
 	return ret;
 }
 
-static int cdns_i3c_master_request_ibi(struct i3c_dev_desc *dev,
-				       const struct i3c_ibi_setup *req)
+static int cdns_i3c_master_find_ibi_slot(struct cdns_i3c_master *master,
+					 struct i3c_dev_desc *dev,
+					 s16 *slot)
 {
-	struct i3c_master_controller *m = i3c_dev_get_master(dev);
-	struct cdns_i3c_master *master = to_cdns_i3c_master(m);
-	struct cdns_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
 	unsigned long flags;
 	unsigned int i;
-
-	data->ibi_pool = i3c_generic_ibi_alloc_pool(dev, req);
-	if (IS_ERR(data->ibi_pool))
-		return PTR_ERR(data->ibi_pool);
+	int ret = -ENOENT;
 
 	spin_lock_irqsave(&master->ibi.lock, flags);
 	for (i = 0; i < master->ibi.num_slots; i++) {
-		if (!master->ibi.slots[i]) {
-			data->ibi = i;
-			master->ibi.slots[i] = dev;
+		/*
+		 * We only need 'SIR' slots to describe IBI-capable devices.
+		 * This slot may be used by mastership request interrupt,
+		 * We can ruse the same 'SIR' map entry.
+		 */
+		if (master->ibi.slots[i] == dev) {
+			*slot = i;
+			ret = 0;
 			break;
 		}
 	}
+
+	if (ret)
+		for (i = 0; i < master->ibi.num_slots; i++) {
+			if (!master->ibi.slots[i]) {
+				master->ibi.slots[i] = dev;
+				*slot = i;
+				ret = 0;
+				break;
+			}
+		}
 	spin_unlock_irqrestore(&master->ibi.lock, flags);
 
-	if (i < master->ibi.num_slots)
+	return ret;
+}
+
+static int cdns_i3c_master_request_ibi(struct i3c_dev_desc *dev,
+				       const struct i3c_ibi_setup *req)
+{
+	struct i3c_master_controller *m = i3c_dev_get_master(dev);
+	struct cdns_i3c_master *master = to_cdns_i3c_master(m);
+	struct cdns_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
+
+	data->ibi_pool = i3c_generic_ibi_alloc_pool(dev, req);
+	if (IS_ERR(data->ibi_pool))
+		return PTR_ERR(data->ibi_pool);
+
+	if (cdns_i3c_master_find_ibi_slot(master, dev, &data->ibi) == 0)
 		return 0;
 
 	i3c_generic_ibi_free_pool(data->ibi_pool);
@@ -1482,6 +1680,51 @@  static int cdns_i3c_master_request_ibi(struct i3c_dev_desc *dev,
 	return -ENOSPC;
 }
 
+static int
+cdns_i3c_master_enable_mastership_events(struct i3c_master_controller *m)
+{
+	struct cdns_i3c_master *master = to_cdns_i3c_master(m);
+	struct cdns_i3c_i2c_dev_data *data;
+	struct i3c_dev_desc *i3cdev;
+	unsigned long flags;
+	u32 sircfg, sirmap;
+	int ret;
+
+	i3c_bus_for_each_i3cdev(&m->bus, i3cdev) {
+		if (I3C_BCR_DEVICE_ROLE(i3cdev->info.bcr) != I3C_BCR_I3C_MASTER)
+			continue;
+
+		data = i3c_dev_get_master_data(i3cdev);
+		if (!data)
+			continue;
+
+		ret = cdns_i3c_master_find_ibi_slot(master, i3cdev, &data->ibi);
+		if (ret)
+			continue;
+
+		spin_lock_irqsave(&master->ibi.lock, flags);
+		sirmap = readl(master->regs + SIR_MAP_DEV_REG(data->ibi));
+		sirmap &= ~SIR_MAP_DEV_CONF_MASK(data->ibi);
+		sircfg = SIR_MAP_DEV_ROLE(i3cdev->info.bcr >> 6) |
+			SIR_MAP_DEV_DA(i3cdev->info.dyn_addr) |
+			SIR_MAP_DEV_PL(i3cdev->info.max_ibi_len) |
+			SIR_MAP_DEV_ACK;
+
+		if (i3cdev->info.bcr & I3C_BCR_MAX_DATA_SPEED_LIM)
+			sircfg |= SIR_MAP_DEV_SLOW;
+
+		sirmap |= SIR_MAP_DEV_CONF(data->ibi, sircfg);
+		writel(sirmap, master->regs + SIR_MAP_DEV_REG(data->ibi));
+		spin_unlock_irqrestore(&master->ibi.lock, flags);
+	}
+
+	/* Unmask Hot-Join and Mastership request interrupts. */
+	i3c_master_enec_locked(&master->base, I3C_BROADCAST_ADDR,
+			       I3C_CCC_EVENT_HJ | I3C_CCC_EVENT_MR);
+
+	return 0;
+}
+
 static void cdns_i3c_master_free_ibi(struct i3c_dev_desc *dev)
 {
 	struct i3c_master_controller *m = i3c_dev_get_master(dev);
@@ -1497,6 +1740,52 @@  static void cdns_i3c_master_free_ibi(struct i3c_dev_desc *dev)
 	i3c_generic_ibi_free_pool(data->ibi_pool);
 }
 
+static int
+cdns_i3c_master_disable_mastership_events(struct i3c_master_controller *m)
+{
+	struct cdns_i3c_master *master = to_cdns_i3c_master(m);
+	struct cdns_i3c_i2c_dev_data *data;
+	struct i3c_dev_desc *i3cdev;
+	unsigned long flags;
+	u32 sirmap;
+	int ret;
+
+	ret = i3c_master_disec_locked(m, I3C_BROADCAST_ADDR,
+				      I3C_CCC_EVENT_MR);
+	if (ret)
+		return ret;
+
+	i3c_bus_for_each_i3cdev(&m->bus, i3cdev) {
+		if (I3C_BCR_DEVICE_ROLE(i3cdev->info.bcr) != I3C_BCR_I3C_MASTER)
+			continue;
+
+		data = i3c_dev_get_master_data(i3cdev);
+
+		ret = cdns_i3c_master_find_ibi_slot(master, i3cdev, &data->ibi);
+		if (ret)
+			continue;
+
+		/*
+		 * Do not modify SIR register and cleanup slots
+		 * if regular IBI is enabled for this device.
+		 */
+		if (master->ibi.slots[data->ibi]->ibi->handler)
+			continue;
+
+		spin_lock_irqsave(&master->ibi.lock, flags);
+		sirmap = readl(master->regs + SIR_MAP_DEV_REG(data->ibi));
+		sirmap &= ~SIR_MAP_DEV_CONF_MASK(data->ibi);
+		sirmap |= SIR_MAP_DEV_CONF(data->ibi,
+					SIR_MAP_DEV_DA(I3C_BROADCAST_ADDR));
+		writel(sirmap, master->regs + SIR_MAP_DEV_REG(data->ibi));
+		spin_unlock_irqrestore(&master->ibi.lock, flags);
+
+		cdns_i3c_master_free_ibi(i3cdev);
+	}
+
+	return ret;
+}
+
 static void cdns_i3c_master_recycle_ibi_slot(struct i3c_dev_desc *dev,
 					     struct i3c_ibi_slot *slot)
 {
@@ -1524,6 +1813,9 @@  static const struct i3c_master_controller_ops cdns_i3c_master_ops = {
 	.request_ibi = cdns_i3c_master_request_ibi,
 	.free_ibi = cdns_i3c_master_free_ibi,
 	.recycle_ibi_slot = cdns_i3c_master_recycle_ibi_slot,
+	.request_mastership = cdns_i3c_sec_master_request_mastership,
+	.enable_mr_events = cdns_i3c_master_enable_mastership_events,
+	.disable_mr_events = cdns_i3c_master_disable_mastership_events
 };
 
 static void cdns_i3c_master_hj(struct work_struct *work)
@@ -1532,13 +1824,84 @@  static void cdns_i3c_master_hj(struct work_struct *work)
 						      struct cdns_i3c_master,
 						      hj_work);
 
-	i3c_master_do_daa(&master->base);
+	if (!master->base.secondary)
+		i3c_master_do_daa(&master->base);
+}
+
+static int cdns_i3c_sec_master_bus_init(struct cdns_i3c_master *master)
+{
+	u32 val;
+	int ret;
+
+	val = readl(master->regs + SLV_STATUS1);
+
+	if (!(val & SLV_STATUS1_HAS_DA))
+		return -EFAULT;
+
+	i3c_bus_maintenance_lock(&master->base.bus);
+	ret = cdns_i3c_sec_master_request_mastership(&master->base);
+	i3c_bus_maintenance_unlock(&master->base.bus);
+
+	return ret;
+}
+
+static void
+cdns_i3c_master_mastership_request(struct cdns_i3c_master *master)
+{
+	int ret;
+
+	ret = cdns_i3c_sec_master_bus_init(master);
+	if (ret)
+		return;
+
+	ret = i3c_master_register(&master->base, master->parent,
+				  &cdns_i3c_master_ops, true);
+	if (ret)
+		dev_err(&master->base.dev, "Master register failed\n");
+}
+
+static void cdns_i3c_master_mastership_handoff(struct cdns_i3c_master *master)
+{
+	int ret;
+
+	struct i3c_dev_desc *dev;
+	u32 ibir = master->mastership.ibir;
+
+	dev = cdns_i3c_get_ibi_device(master, ibir);
+	if (!dev)
+		return;
+
+	ret = i3c_master_mastership_ack(&master->base, dev->info.dyn_addr);
+	if (ret)
+		dev_err(&master->base.dev, "Mastership handoff failed\n");
+}
+
+static void cdns_i3c_master_mastership(struct work_struct *work)
+{
+	struct cdns_i3c_master *master = container_of(work,
+						      struct cdns_i3c_master,
+						      mastership.work);
+
+	switch (master->mastership.mr_type) {
+	case REQUEST:
+		cdns_i3c_master_mastership_request(master);
+		break;
+	case HANDOFF:
+		cdns_i3c_master_mastership_handoff(master);
+		break;
+	case TAKEOVER:
+		cdns_i3c_master_mastership_takeover(master);
+		break;
+	default:
+		break;
+	}
 }
 
 static int cdns_i3c_master_probe(struct platform_device *pdev)
 {
 	struct cdns_i3c_master *master;
 	struct resource *res;
+	bool secondary = false;
 	int ret, irq;
 	u32 val;
 
@@ -1580,6 +1943,9 @@  static int cdns_i3c_master_probe(struct platform_device *pdev)
 	INIT_LIST_HEAD(&master->xferqueue.list);
 
 	INIT_WORK(&master->hj_work, cdns_i3c_master_hj);
+	INIT_WORK(&master->mastership.work,
+		  cdns_i3c_master_mastership);
+
 	writel(0xffffffff, master->regs + MST_IDR);
 	writel(0xffffffff, master->regs + SLV_IDR);
 	ret = devm_request_irq(&pdev->dev, irq, cdns_i3c_master_interrupt, 0,
@@ -1589,6 +1955,10 @@  static int cdns_i3c_master_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, master);
 
+	val = readl(master->regs + MST_STATUS0);
+	if (!(val & MST_STATUS0_MASTER_MODE))
+		secondary = true;
+
 	val = readl(master->regs + CONF_STATUS0);
 
 	/* Device ID0 is reserved to describe this master. */
@@ -1604,6 +1974,7 @@  static int cdns_i3c_master_probe(struct platform_device *pdev)
 
 	spin_lock_init(&master->ibi.lock);
 	master->ibi.num_slots = CONF_STATUS1_IBI_HW_RES(val);
+
 	master->ibi.slots = devm_kcalloc(&pdev->dev, master->ibi.num_slots,
 					 sizeof(*master->ibi.slots),
 					 GFP_KERNEL);
@@ -1612,15 +1983,31 @@  static int cdns_i3c_master_probe(struct platform_device *pdev)
 
 	writel(IBIR_THR(1), master->regs + CMD_IBI_THR_CTRL);
 	writel(MST_INT_IBIR_THR, master->regs + MST_IER);
-	writel(DEVS_CTRL_DEV_CLR_ALL, master->regs + DEVS_CTRL);
+
+	if (secondary) {
+		ret = cdns_i3c_sec_master_bus_init(master);
+		if (ret)
+			goto err_postpone_init;
+	} else
+		writel(DEVS_CTRL_DEV_CLR_ALL, master->regs + DEVS_CTRL);
 
 	ret = i3c_master_register(&master->base, &pdev->dev,
-				  &cdns_i3c_master_ops, false);
+				  &cdns_i3c_master_ops, secondary);
 	if (ret)
 		goto err_disable_sysclk;
 
 	return 0;
 
+err_postpone_init:
+	master->wq = alloc_workqueue("%s", 0, 0, pdev->name);
+	if (!master->wq)
+		return -ENOMEM;
+
+	master->parent = &pdev->dev;
+	writel(SLV_INT_EVENT_UP, master->regs + SLV_IER);
+
+	return 0;
+
 err_disable_sysclk:
 	clk_disable_unprepare(master->sysclk);
 
@@ -1635,6 +2022,9 @@  static int cdns_i3c_master_remove(struct platform_device *pdev)
 	struct cdns_i3c_master *master = platform_get_drvdata(pdev);
 	int ret;
 
+	if (master->wq)
+		destroy_workqueue(master->wq);
+
 	ret = i3c_master_unregister(&master->base);
 	if (ret)
 		return ret;
@@ -1661,6 +2051,7 @@  static struct platform_driver cdns_i3c_master = {
 module_platform_driver(cdns_i3c_master);
 
 MODULE_AUTHOR("Boris Brezillon <boris.brezillon@bootlin.com>");
+MODULE_AUTHOR("Przemyslaw Gaj <pgaj@cadence.com>");
 MODULE_DESCRIPTION("Cadence I3C master driver");
 MODULE_LICENSE("GPL v2");
 MODULE_ALIAS("platform:cdns-i3c-master");