[PATCH v9 17/20] PCI: plda: Add event interrupt codes and host init/deinit functions

[Minda Chen <minda.chen@starfivetech.com>]

PLDA implements new codes and IRQ domain ops like PolarFire.

plda_get_events() adds interrupt register to event num mapping codes
for PLDA local event except DMA engine interrupt events. The DMA engine
interrupt events are implemented by vendors.

Add PLDA host init and deinit functions. So vendor can use it to init
PLDA PCIe host core.

Signed-off-by: Minda Chen <minda.chen@starfivetech.com>
---
 drivers/pci/controller/plda/pcie-plda-host.c | 221 +++++++++++++++++--
 drivers/pci/controller/plda/pcie-plda.h      |  47 ++++
 2 files changed, 255 insertions(+), 13 deletions(-)

diff --git a/drivers/pci/controller/plda/pcie-plda-host.c b/drivers/pci/controller/plda/pcie-plda-host.c
index 4a4a2b5ef8fb..052db70c3128 100644
--- a/drivers/pci/controller/plda/pcie-plda-host.c
+++ b/drivers/pci/controller/plda/pcie-plda-host.c
@@ -3,6 +3,7 @@
  * PLDA PCIe XpressRich host controller driver
  *
  * Copyright (C) 2023 Microchip Co. Ltd
+ *		      StarFive Co. Ltd
  *
  * Author: Daire McNamara <daire.mcnamara@microchip.com>
  */
@@ -257,6 +258,107 @@ static irqreturn_t plda_event_handler(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
+static u32 plda_get_events(struct plda_pcie_rp *port)
+{
+	u32 events, val, origin;
+
+	origin = readl_relaxed(port->bridge_addr + ISTATUS_LOCAL);
+
+	/* Error events and doorbell events */
+	events = (origin & ERROR_AND_DOORBELL_MASK) >> A_ATR_EVT_POST_ERR_SHIFT;
+
+	/* INTx events */
+	if (origin & PM_MSI_INT_INTX_MASK)
+		events |= BIT(EVENT_PM_MSI_INT_INTX);
+
+	/* MSI event and sys events */
+	val = (origin & SYS_AND_MSI_MASK) >> PM_MSI_INT_MSI_SHIFT;
+	events |= val << EVENT_PM_MSI_INT_MSI;
+
+	return events;
+}
+
+static u32 plda_hwirq_to_mask(int hwirq)
+{
+	u32 mask;
+
+	if (hwirq < EVENT_PM_MSI_INT_INTX)
+		mask = BIT(hwirq + A_ATR_EVT_POST_ERR_SHIFT);
+	else if (hwirq == EVENT_PM_MSI_INT_INTX)
+		mask = PM_MSI_INT_INTX_MASK;
+	else
+		mask = BIT(hwirq + PM_MSI_TO_MASK_OFFSET);
+
+	return mask;
+}
+
+static void plda_ack_event_irq(struct irq_data *data)
+{
+	struct plda_pcie_rp *port = irq_data_get_irq_chip_data(data);
+
+	writel_relaxed(plda_hwirq_to_mask(data->hwirq),
+		       port->bridge_addr + ISTATUS_LOCAL);
+}
+
+static void plda_mask_event_irq(struct irq_data *data)
+{
+	struct plda_pcie_rp *port = irq_data_get_irq_chip_data(data);
+	u32 mask, val;
+
+	mask = plda_hwirq_to_mask(data->hwirq);
+
+	raw_spin_lock(&port->lock);
+	val = readl_relaxed(port->bridge_addr + IMASK_LOCAL);
+	val &= ~mask;
+	writel_relaxed(val, port->bridge_addr + IMASK_LOCAL);
+	raw_spin_unlock(&port->lock);
+}
+
+static void plda_unmask_event_irq(struct irq_data *data)
+{
+	struct plda_pcie_rp *port = irq_data_get_irq_chip_data(data);
+	u32 mask, val;
+
+	mask = plda_hwirq_to_mask(data->hwirq);
+
+	raw_spin_lock(&port->lock);
+	val = readl_relaxed(port->bridge_addr + IMASK_LOCAL);
+	val |= mask;
+	writel_relaxed(val, port->bridge_addr + IMASK_LOCAL);
+	raw_spin_unlock(&port->lock);
+}
+
+static struct irq_chip plda_event_irq_chip = {
+	.name = "PLDA PCIe EVENT",
+	.irq_ack = plda_ack_event_irq,
+	.irq_mask = plda_mask_event_irq,
+	.irq_unmask = plda_unmask_event_irq,
+};
+
+static int plda_pcie_event_map(struct irq_domain *domain, unsigned int irq,
+			       irq_hw_number_t hwirq)
+{
+	irq_set_chip_and_handler(irq, &plda_event_irq_chip, handle_level_irq);
+	irq_set_chip_data(irq, domain->host_data);
+
+	return 0;
+}
+
+static const struct irq_domain_ops plda_evt_dom_ops = {
+	.map = plda_pcie_event_map,
+};
+
+static const struct plda_event_ops plda_event_ops = {
+	.get_events = plda_get_events,
+};
+
+static const struct plda_event plda_default_event = {
+	.domain_ops = &plda_evt_dom_ops,
+	.event_ops  = &plda_event_ops,
+	.intx_event = EVENT_PM_MSI_INT_INTX,
+	.msi_event  = EVENT_PM_MSI_INT_MSI
+};
+
 static void plda_handle_event(struct irq_desc *desc)
 {
 	struct plda_pcie_rp *port = irq_desc_get_handler_data(desc);
@@ -320,8 +422,7 @@ int plda_init_interrupts(struct platform_device *pdev,
 			 const struct plda_event *event)
 {
 	struct device *dev = &pdev->dev;
-	int irq;
-	int i, intx_irq, msi_irq, event_irq;
+	int i, event_irq;
 	int ret;
 
 	if (!event->event_ops || !event->event_ops->get_events) {
@@ -335,8 +436,8 @@ int plda_init_interrupts(struct platform_device *pdev,
 		return ret;
 	}
 
-	irq = platform_get_irq(pdev, 0);
-	if (irq < 0)
+	port->irq = platform_get_irq(pdev, 0);
+	if (port->irq < 0)
 		return -ENODEV;
 
 	port->event_ops = event->event_ops;
@@ -360,26 +461,26 @@ int plda_init_interrupts(struct platform_device *pdev,
 		}
 	}
 
-	intx_irq = irq_create_mapping(port->event_domain,
-				      event->intx_event);
-	if (!intx_irq) {
+	port->intx_irq = irq_create_mapping(port->event_domain,
+					    event->intx_event);
+	if (!port->intx_irq) {
 		dev_err(dev, "failed to map INTx interrupt\n");
 		return -ENXIO;
 	}
 
 	/* Plug the INTx chained handler */
-	irq_set_chained_handler_and_data(intx_irq, plda_handle_intx, port);
+	irq_set_chained_handler_and_data(port->intx_irq, plda_handle_intx, port);
 
-	msi_irq = irq_create_mapping(port->event_domain,
-				     event->msi_event);
-	if (!msi_irq)
+	port->msi_irq = irq_create_mapping(port->event_domain,
+					   event->msi_event);
+	if (!port->msi_irq)
 		return -ENXIO;
 
 	/* Plug the MSI chained handler */
-	irq_set_chained_handler_and_data(msi_irq, plda_handle_msi, port);
+	irq_set_chained_handler_and_data(port->msi_irq, plda_handle_msi, port);
 
 	/* Plug the main event chained handler */
-	irq_set_chained_handler_and_data(irq, plda_handle_event, port);
+	irq_set_chained_handler_and_data(port->irq, plda_handle_event, port);
 
 	return 0;
 }
@@ -445,3 +546,97 @@ int plda_pcie_setup_iomems(struct pci_host_bridge *bridge,
 	return 0;
 }
 EXPORT_SYMBOL_GPL(plda_pcie_setup_iomems);
+
+static void plda_pcie_irq_domain_deinit(struct plda_pcie_rp *pcie)
+{
+	irq_set_chained_handler_and_data(pcie->irq, NULL, NULL);
+	irq_set_chained_handler_and_data(pcie->msi_irq, NULL, NULL);
+	irq_set_chained_handler_and_data(pcie->intx_irq, NULL, NULL);
+
+	irq_domain_remove(pcie->msi.msi_domain);
+	irq_domain_remove(pcie->msi.dev_domain);
+
+	irq_domain_remove(pcie->intx_domain);
+	irq_domain_remove(pcie->event_domain);
+}
+
+int plda_pcie_host_init(struct plda_pcie_rp *port, struct pci_ops *ops)
+{
+	struct device *dev = port->dev;
+	struct pci_host_bridge *bridge;
+	struct platform_device *pdev = to_platform_device(dev);
+	struct resource *cfg_res;
+	int ret;
+
+	pdev = to_platform_device(dev);
+
+	port->bridge_addr =
+		devm_platform_ioremap_resource_byname(pdev, "apb");
+
+	if (IS_ERR(port->bridge_addr))
+		return dev_err_probe(dev, PTR_ERR(port->bridge_addr),
+				     "failed to map reg memory\n");
+
+	cfg_res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
+	if (!cfg_res)
+		return dev_err_probe(dev, -ENODEV,
+				     "failed to get config memory\n");
+
+	port->config_base = devm_ioremap_resource(dev, cfg_res);
+	if (IS_ERR(port->config_base))
+		return dev_err_probe(dev, PTR_ERR(port->config_base),
+				     "failed to map config memory\n");
+
+	bridge = devm_pci_alloc_host_bridge(dev, 0);
+	if (!bridge)
+		return dev_err_probe(dev, -ENOMEM,
+				     "failed to alloc bridge\n");
+
+	if (port->host_ops && port->host_ops->host_init) {
+		ret = port->host_ops->host_init(port);
+		if (ret)
+			return ret;
+	}
+
+	port->bridge = bridge;
+	plda_pcie_setup_window(port->bridge_addr, 0, cfg_res->start, 0,
+			       resource_size(cfg_res));
+	plda_pcie_setup_iomems(bridge, port);
+	plda_set_default_msi(&port->msi);
+	ret = plda_init_interrupts(pdev, port, &plda_default_event);
+	if (ret)
+		goto err_host;
+
+	/* Set default bus ops */
+	bridge->ops = ops;
+	bridge->sysdata = port;
+
+	ret = pci_host_probe(bridge);
+	if (ret < 0) {
+		dev_err_probe(dev, ret, "failed to probe pci host\n");
+		goto err_probe;
+	}
+
+	return ret;
+
+err_probe:
+	plda_pcie_irq_domain_deinit(port);
+err_host:
+	if (port->host_ops && port->host_ops->host_deinit)
+		port->host_ops->host_deinit(port);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(plda_pcie_host_init);
+
+void plda_pcie_host_deinit(struct plda_pcie_rp *port)
+{
+	pci_stop_root_bus(port->bridge->bus);
+	pci_remove_root_bus(port->bridge->bus);
+
+	plda_pcie_irq_domain_deinit(port);
+
+	if (port->host_ops && port->host_ops->host_deinit)
+		port->host_ops->host_deinit(port);
+}
+EXPORT_SYMBOL_GPL(plda_pcie_host_deinit);
diff --git a/drivers/pci/controller/plda/pcie-plda.h b/drivers/pci/controller/plda/pcie-plda.h
index ce7787aef4b7..ed99a51dd6e8 100644
--- a/drivers/pci/controller/plda/pcie-plda.h
+++ b/drivers/pci/controller/plda/pcie-plda.h
@@ -40,6 +40,7 @@
 #define  P_ATR_EVT_DISCARD_ERR_SHIFT		22
 #define  P_ATR_EVT_DOORBELL_MASK		0x00000000u
 #define  P_ATR_EVT_DOORBELL_SHIFT		23
+#define  ERROR_AND_DOORBELL_MASK		GENMASK(23, 16)
 #define  PM_MSI_INT_INTA_MASK			0x01000000u
 #define  PM_MSI_INT_INTA_SHIFT			24
 #define  PM_MSI_INT_INTB_MASK			0x02000000u
@@ -58,6 +59,7 @@
 #define  PM_MSI_INT_EVENTS_SHIFT		30
 #define  PM_MSI_INT_SYS_ERR_MASK		0x80000000u
 #define  PM_MSI_INT_SYS_ERR_SHIFT		31
+#define  SYS_AND_MSI_MASK			GENMASK(31, 28)
 #define  NUM_LOCAL_EVENTS			15
 #define ISTATUS_LOCAL				0x184
 #define IMASK_HOST				0x188
@@ -102,12 +104,43 @@
 #define EVENT_PM_MSI_INT_SYS_ERR		12
 #define NUM_PLDA_EVENTS				13
 
+/*
+ * PLDA local interrupt register
+ *
+ * 31         27     23              15           7          0
+ * +--+--+--+-+------+-+-+-+-+-+-+-+-+-----------+-----------+
+ * |12|11|10|9| intx |7|6|5|4|3|2|1|0| DMA error | DMA end   |
+ * +--+--+--+-+------+-+-+-+-+-+-+-+-+-----------+-----------+
+ * 0:  AXI post error
+ * 1:  AXI fetch error
+ * 2:  AXI discard error
+ * 3:  AXI doorbell
+ * 4:  PCIe post error
+ * 5:  PCIe fetch error
+ * 6:  PCIe discard error
+ * 7:  PCIe doorbell
+ * 8:  4 INTx interruts
+ * 9:  MSI interrupt
+ * 10: AER event
+ * 11: PM/LTR/Hotplug
+ * 12: System error
+ * DMA error : reserved for vendor implement
+ * DMA end : reserved for vendor implement
+ */
+
+#define PM_MSI_TO_MASK_OFFSET			19
+
 struct plda_pcie_rp;
 
 struct plda_event_ops {
 	u32 (*get_events)(struct plda_pcie_rp *pcie);
 };
 
+struct plda_pcie_host_ops {
+	int (*host_init)(struct plda_pcie_rp *pcie);
+	void (*host_deinit)(struct plda_pcie_rp *pcie);
+};
+
 struct plda_msi {
 	struct mutex lock;		/* Protect used bitmap */
 	struct irq_domain *msi_domain;
@@ -119,12 +152,18 @@ struct plda_msi {
 
 struct plda_pcie_rp {
 	struct device *dev;
+	struct pci_host_bridge *bridge;
 	struct irq_domain *intx_domain;
 	struct irq_domain *event_domain;
 	raw_spinlock_t lock;
 	struct plda_msi msi;
 	const struct plda_event_ops *event_ops;
+	const struct plda_pcie_host_ops *host_ops;
 	void __iomem *bridge_addr;
+	void __iomem *config_base;
+	int irq;
+	int msi_irq;
+	int intx_irq;
 	int num_events;
 };
 
@@ -145,4 +184,12 @@ void plda_pcie_setup_window(void __iomem *bridge_base_addr, u32 index,
 			    size_t size);
 int plda_pcie_setup_iomems(struct pci_host_bridge *bridge,
 			   struct plda_pcie_rp *port);
+int plda_pcie_host_init(struct plda_pcie_rp *pcie, struct pci_ops *ops);
+void plda_pcie_host_deinit(struct plda_pcie_rp *pcie);
+
+static inline void plda_set_default_msi(struct plda_msi *msi)
+{
+	msi->vector_phy = IMSI_ADDR;
+	msi->num_vectors = PLDA_MAX_NUM_MSI_IRQS;
+}
 #endif
-- 
2.17.1