1 files changed, 369 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-mvebu-icu.c b/drivers/irqchip/irq-mvebu-icu.c
new file mode 100644
index 000000000000..db5dbc6e88b0
--- /dev/null
+++ b/drivers/irqchip/irq-mvebu-icu.c
@@ -0,0 +1,369 @@
+/*
+ * Copyright (C) 2017 Marvell
+ *
+ * Hanna Hawa <hannah@marvell.com>
+ * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqchip.h>
+#include <linux/irqdomain.h>
+#include <linux/jump_label.h>
+#include <linux/kernel.h>
+#include <linux/msi.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+
+#include <linux/irqchip/irq-msi-lib.h>
+
+#include <dt-bindings/interrupt-controller/mvebu-icu.h>
+
+/* ICU registers */
+#define ICU_SETSPI_NSR_AL	0x10
+#define ICU_SETSPI_NSR_AH	0x14
+#define ICU_CLRSPI_NSR_AL	0x18
+#define ICU_CLRSPI_NSR_AH	0x1c
+#define ICU_SET_SEI_AL		0x50
+#define ICU_SET_SEI_AH		0x54
+#define ICU_CLR_SEI_AL		0x58
+#define ICU_CLR_SEI_AH		0x5C
+#define ICU_INT_CFG(x)          (0x100 + 4 * (x))
+#define   ICU_INT_ENABLE	BIT(24)
+#define   ICU_IS_EDGE		BIT(28)
+#define   ICU_GROUP_SHIFT	29
+
+/* ICU definitions */
+#define ICU_MAX_IRQS		207
+#define ICU_SATA0_ICU_ID	109
+#define ICU_SATA1_ICU_ID	107
+
+struct mvebu_icu_subset_data {
+	unsigned int icu_group;
+	unsigned int offset_set_ah;
+	unsigned int offset_set_al;
+	unsigned int offset_clr_ah;
+	unsigned int offset_clr_al;
+};
+
+struct mvebu_icu {
+	void __iomem *base;
+	struct device *dev;
+};
+
+struct mvebu_icu_msi_data {
+	struct mvebu_icu *icu;
+	atomic_t initialized;
+	const struct mvebu_icu_subset_data *subset_data;
+};
+
+static DEFINE_STATIC_KEY_FALSE(legacy_bindings);
+
+static int mvebu_icu_translate(struct irq_domain *d, struct irq_fwspec *fwspec,
+			       unsigned long *hwirq, unsigned int *type)
+{
+	unsigned int param_count = static_branch_unlikely(&legacy_bindings) ? 3 : 2;
+	struct msi_domain_info *info = d->host_data;
+	struct mvebu_icu_msi_data *msi_data = info->chip_data;
+	struct mvebu_icu *icu = msi_data->icu;
+
+	/* Check the count of the parameters in dt */
+	if (WARN_ON(fwspec->param_count != param_count)) {
+		dev_err(icu->dev, "wrong ICU parameter count %d\n",
+			fwspec->param_count);
+		return -EINVAL;
+	}
+
+	if (static_branch_unlikely(&legacy_bindings)) {
+		*hwirq = fwspec->param[1];
+		*type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK;
+		if (fwspec->param[0] != ICU_GRP_NSR) {
+			dev_err(icu->dev, "wrong ICU group type %x\n",
+				fwspec->param[0]);
+			return -EINVAL;
+		}
+	} else {
+		*hwirq = fwspec->param[0];
+		*type = fwspec->param[1] & IRQ_TYPE_SENSE_MASK;
+
+		/*
+		 * The ICU receives level interrupts. While the NSR are also
+		 * level interrupts, SEI are edge interrupts. Force the type
+		 * here in this case. Please note that this makes the interrupt
+		 * handling unreliable.
+		 */
+		if (msi_data->subset_data->icu_group == ICU_GRP_SEI)
+			*type = IRQ_TYPE_EDGE_RISING;
+	}
+
+	if (*hwirq >= ICU_MAX_IRQS) {
+		dev_err(icu->dev, "invalid interrupt number %ld\n", *hwirq);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static void mvebu_icu_init(struct mvebu_icu *icu,
+			   struct mvebu_icu_msi_data *msi_data,
+			   struct msi_msg *msg)
+{
+	const struct mvebu_icu_subset_data *subset = msi_data->subset_data;
+
+	if (atomic_cmpxchg(&msi_data->initialized, false, true))
+		return;
+
+	/* Set 'SET' ICU SPI message address in AP */
+	writel_relaxed(msg[0].address_hi, icu->base + subset->offset_set_ah);
+	writel_relaxed(msg[0].address_lo, icu->base + subset->offset_set_al);
+
+	if (subset->icu_group != ICU_GRP_NSR)
+		return;
+
+	/* Set 'CLEAR' ICU SPI message address in AP (level-MSI only) */
+	writel_relaxed(msg[1].address_hi, icu->base + subset->offset_clr_ah);
+	writel_relaxed(msg[1].address_lo, icu->base + subset->offset_clr_al);
+}
+
+static int mvebu_icu_msi_init(struct irq_domain *domain, struct msi_domain_info *info,
+			      unsigned int virq, irq_hw_number_t hwirq, msi_alloc_info_t *arg)
+{
+	irq_domain_set_hwirq_and_chip(domain, virq, hwirq, info->chip, info->chip_data);
+	return irq_set_irqchip_state(virq, IRQCHIP_STATE_PENDING, false);
+}
+
+static void mvebu_icu_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc)
+{
+	arg->desc = desc;
+	arg->hwirq = (u32)desc->data.icookie.value;
+}
+
+static void mvebu_icu_write_msi_msg(struct irq_data *d, struct msi_msg *msg)
+{
+	struct mvebu_icu_msi_data *msi_data = d->chip_data;
+	unsigned int icu_group = msi_data->subset_data->icu_group;
+	struct msi_desc *desc = irq_data_get_msi_desc(d);
+	struct mvebu_icu *icu = msi_data->icu;
+	unsigned int type;
+	u32 icu_int;
+
+	if (msg->address_lo || msg->address_hi) {
+		/* One off initialization per domain */
+		mvebu_icu_init(icu, msi_data, msg);
+		/* Configure the ICU with irq number & type */
+		icu_int = msg->data | ICU_INT_ENABLE;
+		type = (unsigned int)(desc->data.icookie.value >> 32);
+		if (type & IRQ_TYPE_EDGE_RISING)
+			icu_int |= ICU_IS_EDGE;
+		icu_int |= icu_group << ICU_GROUP_SHIFT;
+	} else {
+		/* De-configure the ICU */
+		icu_int = 0;
+	}
+
+	writel_relaxed(icu_int, icu->base + ICU_INT_CFG(d->hwirq));
+
+	/*
+	 * The SATA unit has 2 ports, and a dedicated ICU entry per
+	 * port. The ahci sata driver supports only one irq interrupt
+	 * per SATA unit. To solve this conflict, we configure the 2
+	 * SATA wired interrupts in the south bridge into 1 GIC
+	 * interrupt in the north bridge. Even if only a single port
+	 * is enabled, if sata node is enabled, both interrupts are
+	 * configured (regardless of which port is actually in use).
+	 */
+	if (d->hwirq == ICU_SATA0_ICU_ID || d->hwirq == ICU_SATA1_ICU_ID) {
+		writel_relaxed(icu_int, icu->base + ICU_INT_CFG(ICU_SATA0_ICU_ID));
+		writel_relaxed(icu_int, icu->base + ICU_INT_CFG(ICU_SATA1_ICU_ID));
+	}
+}
+
+static const struct msi_domain_template mvebu_icu_nsr_msi_template = {
+	.chip = {
+		.name			= "ICU-NSR",
+		.irq_mask		= irq_chip_mask_parent,
+		.irq_unmask		= irq_chip_unmask_parent,
+		.irq_eoi		= irq_chip_eoi_parent,
+		.irq_set_type		= irq_chip_set_type_parent,
+		.irq_write_msi_msg	= mvebu_icu_write_msi_msg,
+		.flags			= IRQCHIP_SUPPORTS_LEVEL_MSI,
+	},
+
+	.ops = {
+		.msi_translate		= mvebu_icu_translate,
+		.msi_init		= mvebu_icu_msi_init,
+		.set_desc		= mvebu_icu_set_desc,
+	},
+
+	.info = {
+		.bus_token		= DOMAIN_BUS_WIRED_TO_MSI,
+		.flags			= MSI_FLAG_LEVEL_CAPABLE |
+					  MSI_FLAG_USE_DEV_FWNODE,
+	},
+};
+
+static const struct msi_domain_template mvebu_icu_sei_msi_template = {
+	.chip = {
+		.name			= "ICU-SEI",
+		.irq_mask		= irq_chip_mask_parent,
+		.irq_unmask		= irq_chip_unmask_parent,
+		.irq_ack		= irq_chip_ack_parent,
+		.irq_set_type		= irq_chip_set_type_parent,
+		.irq_write_msi_msg	= mvebu_icu_write_msi_msg,
+		.flags			= IRQCHIP_SUPPORTS_LEVEL_MSI,
+	},
+
+	.ops = {
+		.msi_translate		= mvebu_icu_translate,
+		.msi_init		= mvebu_icu_msi_init,
+		.set_desc		= mvebu_icu_set_desc,
+	},
+
+	.info = {
+		.bus_token		= DOMAIN_BUS_WIRED_TO_MSI,
+		.flags			= MSI_FLAG_LEVEL_CAPABLE |
+					  MSI_FLAG_USE_DEV_FWNODE,
+	},
+};
+
+static const struct mvebu_icu_subset_data mvebu_icu_nsr_subset_data = {
+	.icu_group = ICU_GRP_NSR,
+	.offset_set_ah = ICU_SETSPI_NSR_AH,
+	.offset_set_al = ICU_SETSPI_NSR_AL,
+	.offset_clr_ah = ICU_CLRSPI_NSR_AH,
+	.offset_clr_al = ICU_CLRSPI_NSR_AL,
+};
+
+static const struct mvebu_icu_subset_data mvebu_icu_sei_subset_data = {
+	.icu_group = ICU_GRP_SEI,
+	.offset_set_ah = ICU_SET_SEI_AH,
+	.offset_set_al = ICU_SET_SEI_AL,
+};
+
+static const struct of_device_id mvebu_icu_subset_of_match[] = {
+	{
+		.compatible = "marvell,cp110-icu-nsr",
+		.data = &mvebu_icu_nsr_subset_data,
+	},
+	{
+		.compatible = "marvell,cp110-icu-sei",
+		.data = &mvebu_icu_sei_subset_data,
+	},
+	{},
+};
+
+static int mvebu_icu_subset_probe(struct platform_device *pdev)
+{
+	const struct msi_domain_template *tmpl;
+	struct mvebu_icu_msi_data *msi_data;
+	struct device *dev = &pdev->dev;
+	bool sei;
+
+	msi_data = devm_kzalloc(dev, sizeof(*msi_data), GFP_KERNEL);
+	if (!msi_data)
+		return -ENOMEM;
+
+	if (static_branch_unlikely(&legacy_bindings)) {
+		msi_data->icu = dev_get_drvdata(dev);
+		msi_data->subset_data = &mvebu_icu_nsr_subset_data;
+	} else {
+		msi_data->icu = dev_get_drvdata(dev->parent);
+		msi_data->subset_data = of_device_get_match_data(dev);
+	}
+
+	dev->msi.domain = of_msi_get_domain(dev, dev->of_node, DOMAIN_BUS_PLATFORM_MSI);
+	if (!dev->msi.domain)
+		return -EPROBE_DEFER;
+
+	if (!irq_domain_get_of_node(dev->msi.domain))
+		return -ENODEV;
+
+	sei = msi_data->subset_data->icu_group == ICU_GRP_SEI;
+	tmpl = sei ? &mvebu_icu_sei_msi_template : &mvebu_icu_nsr_msi_template;
+
+	if (!msi_create_device_irq_domain(dev, MSI_DEFAULT_DOMAIN, tmpl,
+					  ICU_MAX_IRQS, NULL, msi_data)) {
+		dev_err(dev, "Failed to create ICU MSI domain\n");
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static struct platform_driver mvebu_icu_subset_driver = {
+	.probe  = mvebu_icu_subset_probe,
+	.driver = {
+		.name = "mvebu-icu-subset",
+		.of_match_table = mvebu_icu_subset_of_match,
+	},
+};
+builtin_platform_driver(mvebu_icu_subset_driver);
+
+static int mvebu_icu_probe(struct platform_device *pdev)
+{
+	struct mvebu_icu *icu;
+	int i;
+
+	icu = devm_kzalloc(&pdev->dev, sizeof(struct mvebu_icu),
+			   GFP_KERNEL);
+	if (!icu)
+		return -ENOMEM;
+
+	icu->dev = &pdev->dev;
+
+	icu->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(icu->base))
+		return PTR_ERR(icu->base);
+
+	/*
+	 * Legacy bindings: ICU is one node with one MSI parent: force manually
+	 *                  the probe of the NSR interrupts side.
+	 * New bindings: ICU node has children, one per interrupt controller
+	 *               having its own MSI parent: call platform_populate().
+	 * All ICU instances should use the same bindings.
+	 */
+	if (!of_get_child_count(pdev->dev.of_node))
+		static_branch_enable(&legacy_bindings);
+
+	/*
+	 * Clean all ICU interrupts of type NSR and SEI, required to
+	 * avoid unpredictable SPI assignments done by firmware.
+	 */
+	for (i = 0 ; i < ICU_MAX_IRQS ; i++) {
+		u32 icu_int, icu_grp;
+
+		icu_int = readl_relaxed(icu->base + ICU_INT_CFG(i));
+		icu_grp = icu_int >> ICU_GROUP_SHIFT;
+
+		if (icu_grp == ICU_GRP_NSR ||
+		    (icu_grp == ICU_GRP_SEI &&
+		     !static_branch_unlikely(&legacy_bindings)))
+			writel_relaxed(0x0, icu->base + ICU_INT_CFG(i));
+	}
+
+	platform_set_drvdata(pdev, icu);
+
+	if (static_branch_unlikely(&legacy_bindings))
+		return mvebu_icu_subset_probe(pdev);
+	else
+		return devm_of_platform_populate(&pdev->dev);
+}
+
+static const struct of_device_id mvebu_icu_of_match[] = {
+	{ .compatible = "marvell,cp110-icu", },
+	{},
+};
+
+static struct platform_driver mvebu_icu_driver = {
+	.probe  = mvebu_icu_probe,
+	.driver = {
+		.name = "mvebu-icu",
+		.of_match_table = mvebu_icu_of_match,
+	},
+};
+builtin_platform_driver(mvebu_icu_driver);