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From:   Minda Chen <minda.chen@starfivetech.com>
To:     Conor Dooley <conor@kernel.org>,
        =?UTF-8?q?Krzysztof=20Wilczy=C5=84ski?= <kw@linux.com>,
        Rob Herring <robh+dt@kernel.org>,
        Bjorn Helgaas <bhelgaas@google.com>,
        Lorenzo Pieralisi <lpieralisi@kernel.org>,
        "Daire McNamara" <daire.mcnamara@microchip.com>,
        Emil Renner Berthing <emil.renner.berthing@canonical.com>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>
CC:     <devicetree@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <linux-riscv@lists.infradead.org>, <linux-pci@vger.kernel.org>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        Philipp Zabel <p.zabel@pengutronix.de>,
        Mason Huo <mason.huo@starfivetech.com>,
        Leyfoon Tan <leyfoon.tan@starfivetech.com>,
        Kevin Xie <kevin.xie@starfivetech.com>,
        Minda Chen <minda.chen@starfivetech.com>
Subject: [PATCH v13 14/21] PCI: microchip: Add get_events() callback and add PLDA get_event()
Date:   Thu, 14 Dec 2023 15:28:32 +0800
Message-ID: <20231214072839.2367-15-minda.chen@starfivetech.com>
In-Reply-To: <20231214072839.2367-1-minda.chen@starfivetech.com>
References: <20231214072839.2367-1-minda.chen@starfivetech.com>
MIME-Version: 1.0
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Precedence: bulk

PolarFire implements its own PCIe interrupts, additional to the regular
PCIe interrupts, due to lack of an MSI controller, so the interrupt to
event number mapping is different to the PLDA local interrupts,
necessitating a custom get_events() implementation.

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

Signed-off-by: Minda Chen <minda.chen@starfivetech.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
---
 .../pci/controller/plda/pcie-microchip-host.c | 35 ++++++++++++++++++-
 drivers/pci/controller/plda/pcie-plda.h       | 33 +++++++++++++++++
 2 files changed, 67 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/controller/plda/pcie-microchip-host.c b/drivers/pci/controller/plda/pcie-microchip-host.c
index 00250781b11c..fd0d92c3d03f 100644
--- a/drivers/pci/controller/plda/pcie-microchip-host.c
+++ b/drivers/pci/controller/plda/pcie-microchip-host.c
@@ -627,6 +627,26 @@ static u32 mc_get_events(struct plda_pcie_rp *port)
 	return events;
 }
 
+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 irqreturn_t mc_event_handler(int irq, void *dev_id)
 {
 	struct plda_pcie_rp *port = dev_id;
@@ -657,7 +677,7 @@ static void plda_handle_event(struct irq_desc *desc)
 
 	chained_irq_enter(chip, desc);
 
-	events = mc_get_events(port);
+	events = port->event_ops->get_events(port);
 
 	for_each_set_bit(bit, &events, port->num_events)
 		generic_handle_domain_irq(port->event_domain, bit);
@@ -751,6 +771,10 @@ static struct irq_chip mc_event_irq_chip = {
 	.irq_unmask = mc_unmask_event_irq,
 };
 
+static const struct plda_event_ops plda_event_ops = {
+	.get_events = plda_get_events,
+};
+
 static int plda_pcie_event_map(struct irq_domain *domain, unsigned int irq,
 			       irq_hw_number_t hwirq)
 {
@@ -816,6 +840,10 @@ static int mc_request_event_irq(struct plda_pcie_rp *plda, int event_irq,
 				0, event_cause[event].sym, plda);
 }
 
+static const struct plda_event_ops mc_event_ops = {
+	.get_events = mc_get_events,
+};
+
 static const struct plda_event mc_event = {
 	.request_event_irq = mc_request_event_irq,
 	.intx_event        = EVENT_LOCAL_PM_MSI_INT_INTX,
@@ -932,6 +960,9 @@ static int plda_init_interrupts(struct platform_device *pdev,
 	int i, intx_irq, msi_irq, event_irq;
 	int ret;
 
+	if (!port->event_ops)
+		port->event_ops = &plda_event_ops;
+
 	ret = plda_pcie_init_irq_domains(port);
 	if (ret) {
 		dev_err(dev, "failed creating IRQ domains\n");
@@ -1008,6 +1039,8 @@ static int mc_platform_init(struct pci_config_window *cfg)
 	if (ret)
 		return ret;
 
+	port->plda.event_ops = &mc_event_ops;
+
 	/* Address translation is up; safe to enable interrupts */
 	ret = plda_init_interrupts(pdev, &port->plda, &mc_event);
 	if (ret)
diff --git a/drivers/pci/controller/plda/pcie-plda.h b/drivers/pci/controller/plda/pcie-plda.h
index fba7343f9a96..dd8bc2750bfc 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
@@ -102,6 +104,36 @@
 #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
+ */
+
+struct plda_pcie_rp;
+
+struct plda_event_ops {
+	u32 (*get_events)(struct plda_pcie_rp *pcie);
+};
+
 struct plda_msi {
 	struct mutex lock;		/* Protect used bitmap */
 	struct irq_domain *msi_domain;
@@ -117,6 +149,7 @@ struct plda_pcie_rp {
 	struct irq_domain *event_domain;
 	raw_spinlock_t lock;
 	struct plda_msi msi;
+	const struct plda_event_ops *event_ops;
 	void __iomem *bridge_addr;
 	int num_events;
 };
-- 
2.17.1