[PATCH] irqchip: irq-mvebu-odmi: new driver

From: Thomas Petazzoni
Date: Mon Feb 15 2016 - 02:43:22 EST


This commits adds a new irqchip driver that handles the ODMI
controller found on Marvell 7K/8K processors. The ODMI controller
provide MSI interrupt functionality to on-board peripherals, much like
the GIC-v2m.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx>
---
.../marvell,odmi-controller.txt | 36 +++
drivers/irqchip/Kconfig | 4 +
drivers/irqchip/Makefile | 1 +
drivers/irqchip/irq-mvebu-odmi.c | 270 +++++++++++++++++++++
4 files changed, 311 insertions(+)
create mode 100644 Documentation/devicetree/bindings/interrupt-controller/marvell,odmi-controller.txt
create mode 100644 drivers/irqchip/irq-mvebu-odmi.c

diff --git a/Documentation/devicetree/bindings/interrupt-controller/marvell,odmi-controller.txt b/Documentation/devicetree/bindings/interrupt-controller/marvell,odmi-controller.txt
new file mode 100644
index 0000000..a2470af
--- /dev/null
+++ b/Documentation/devicetree/bindings/interrupt-controller/marvell,odmi-controller.txt
@@ -0,0 +1,36 @@
+
+* Marvell ODMI for MSI support
+
+Some Marvell SoCs have an On-Die Message Interrupt (ODMI) controller
+which can be used by on-board peripheral for MSI interrupts.
+
+Required properties:
+
+- compatible : The value here should contain "marvell,odmi-controller".
+
+- interrupt,controller : Identifies the node as an interrupt controller.
+
+- msi-controller : Identifies the node as an MSI controller.
+
+- marvell,odmi-frames : Number of ODMI frames available. Each frame
+ provides a number of events.
+
+- reg : List of register definitions, one for each
+ ODMI frame.
+
+- marvell,spi-base : List of GIC base SPI interrupts, one for each
+ ODMI frame.
+
+Example:
+
+ odmi: odmi@300000 {
+ compatible = "marvell,odmi-controller";
+ interrupt-controller;
+ msi-controller;
+ marvell,odmi-frames = <4>;
+ reg = <0x300000 0x4000>,
+ <0x304000 0x4000>,
+ <0x308000 0x4000>,
+ <0x30C000 0x4000>;
+ marvell,spi-base = <128>, <136>, <144>, <152>;
+ };
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 715923d..18bed3c 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -217,3 +217,7 @@ config IRQ_MXS
def_bool y if MACH_ASM9260 || ARCH_MXS
select IRQ_DOMAIN
select STMP_DEVICE
+
+config MVEBU_ODMI
+ bool
+ select GENERIC_MSI_IRQ_DOMAIN
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 18caacb..29c388f 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -59,3 +59,4 @@ obj-$(CONFIG_ARCH_SA1100) += irq-sa11x0.o
obj-$(CONFIG_INGENIC_IRQ) += irq-ingenic.o
obj-$(CONFIG_IMX_GPCV2) += irq-imx-gpcv2.o
obj-$(CONFIG_PIC32_EVIC) += irq-pic32-evic.o
+obj-$(CONFIG_MVEBU_ODMI) += irq-mvebu-odmi.o
diff --git a/drivers/irqchip/irq-mvebu-odmi.c b/drivers/irqchip/irq-mvebu-odmi.c
new file mode 100644
index 0000000..c3e00b9
--- /dev/null
+++ b/drivers/irqchip/irq-mvebu-odmi.c
@@ -0,0 +1,270 @@
+/*
+ * Copyright (C) 2016 Marvell
+ *
+ * Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx>
+ *
+ * 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.
+ */
+
+#define pr_fmt(fmt) "GIC-ODMI: " fmt
+
+#include <linux/irq.h>
+#include <linux/irqchip.h>
+#include <linux/irqdomain.h>
+#include <linux/kernel.h>
+#include <linux/msi.h>
+#include <linux/of_address.h>
+#include <linux/slab.h>
+#include <dt-bindings/interrupt-controller/arm-gic.h>
+
+#define GICP_ODMIN_SET 0x40
+#define GICP_ODMI_INT_NUM_SHIFT 12
+#define GICP_ODMIN_GM_EP_R0 0x110
+#define GICP_ODMIN_GM_EP_R1 0x114
+#define GICP_ODMIN_GM_EA_R0 0x108
+#define GICP_ODMIN_GM_EA_R1 0x118
+
+/*
+ * We don't support the group events, so we simply have 8 interrupts
+ * per frame.
+ */
+#define NODMIS_PER_FRAME 8
+
+struct odmi_data {
+ struct resource res;
+ void __iomem *base;
+ unsigned int spi_base;
+ unsigned long bm;
+};
+
+static struct odmi_data *odmis;
+static unsigned int odmis_count;
+
+/*
+ * Lock protecting the allocation bitmap embedded in the odmi_data
+ * structure. Only one spinlock is used, since allocation/freeing of
+ * MSI interrupts is infrequent.
+ */
+static DEFINE_SPINLOCK(odmis_lock);
+
+static int odmi_set_affinity(struct irq_data *irq_data,
+ const struct cpumask *mask, bool force)
+{
+ int ret;
+
+ ret = irq_chip_set_affinity_parent(irq_data, mask, force);
+ if (ret == IRQ_SET_MASK_OK)
+ ret = IRQ_SET_MASK_OK_DONE;
+
+ return ret;
+}
+
+static void odmi_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
+{
+ struct odmi_data *odmi = NULL;
+ phys_addr_t addr;
+ unsigned int odmi_offset, i;
+
+ /* Search the ODMI frame handling this interrupt */
+ for (i = 0; i < odmis_count; i++) {
+ if (data->hwirq >= odmis[i].spi_base &&
+ data->hwirq < (odmis[i].spi_base + NODMIS_PER_FRAME)) {
+ odmi = &odmis[i];
+ break;
+ }
+ }
+
+ if (WARN_ON(!odmi))
+ return;
+
+ odmi_offset = (data->hwirq - odmi->spi_base);
+
+ addr = odmi->res.start + GICP_ODMIN_SET;
+
+ msg->address_hi = upper_32_bits(addr);
+ msg->address_lo = lower_32_bits(addr);
+ msg->data = odmi_offset << GICP_ODMI_INT_NUM_SHIFT;
+}
+
+static struct irq_chip odmi_irq_chip = {
+ .name = "ODMI",
+ .irq_mask = irq_chip_mask_parent,
+ .irq_unmask = irq_chip_unmask_parent,
+ .irq_eoi = irq_chip_eoi_parent,
+ .irq_set_affinity = odmi_set_affinity,
+ .irq_compose_msi_msg = odmi_compose_msi_msg,
+};
+
+static int odmi_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs, void *args)
+{
+ struct odmi_data *odmi = NULL;
+ struct irq_fwspec fwspec;
+ struct irq_data *d;
+ unsigned int offset, hwirq;
+ int i, ret;
+
+ spin_lock(&odmis_lock);
+ for (i = 0; i < odmis_count; i++) {
+ offset = find_first_zero_bit(&odmis[i].bm, NODMIS_PER_FRAME);
+ if (offset < NODMIS_PER_FRAME) {
+ __set_bit(offset, &odmis[i].bm);
+ odmi = &odmis[i];
+ break;
+ }
+ }
+ spin_unlock(&odmis_lock);
+
+ if (!odmi)
+ return -ENOSPC;
+
+ hwirq = odmi->spi_base + offset;
+
+ fwspec.fwnode = domain->parent->fwnode;
+ fwspec.param_count = 3;
+ fwspec.param[0] = GIC_SPI;
+ fwspec.param[1] = hwirq - 32;
+ fwspec.param[2] = IRQ_TYPE_EDGE_RISING;
+
+ ret = irq_domain_alloc_irqs_parent(domain, virq, 1, &fwspec);
+ if (ret) {
+ pr_err("Cannot allocate parent IRQ\n");
+ spin_lock(&odmis_lock);
+ __clear_bit(offset, &odmi->bm);
+ spin_unlock(&odmis_lock);
+ return ret;
+ }
+
+ /* Configure the interrupt line to be edge */
+ d = irq_domain_get_irq_data(domain->parent, virq);
+ d->chip->irq_set_type(d, IRQ_TYPE_EDGE_RISING);
+
+ irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
+ &odmi_irq_chip, NULL);
+
+ return 0;
+}
+
+static void odmi_irq_domain_free(struct irq_domain *domain,
+ unsigned int virq, unsigned int nr_irqs)
+{
+ struct irq_data *d = irq_domain_get_irq_data(domain, virq);
+ struct odmi_data *odmi = NULL;
+ unsigned int offset;
+ int i;
+
+ /*
+ * Check if the hwirq number is valid, and if so, to which
+ * ODMI frame it belongs
+ */
+ spin_lock(&odmis_lock);
+ for (i = 0; i < odmis_count; i++) {
+ if (d->hwirq >= odmis[i].spi_base &&
+ d->hwirq < (odmis[i].spi_base + NODMIS_PER_FRAME)) {
+ odmi = &odmis[i];
+ offset = d->hwirq - odmis[i].spi_base;
+ break;
+ }
+ }
+ spin_unlock(&odmis_lock);
+
+ if (!odmi) {
+ pr_err("Failed to teardown msi. Invalid hwirq %lu\n", d->hwirq);
+ return;
+ }
+
+ irq_domain_free_irqs_parent(domain, virq, nr_irqs);
+
+ /* Actually free the MSI */
+ spin_lock(&odmis_lock);
+ __clear_bit(offset, &odmi->bm);
+ spin_unlock(&odmis_lock);
+}
+
+static const struct irq_domain_ops odmi_domain_ops = {
+ .alloc = odmi_irq_domain_alloc,
+ .free = odmi_irq_domain_free,
+};
+
+static struct irq_chip odmi_msi_irq_chip = {
+ .name = "ODMI",
+};
+
+static struct msi_domain_ops odmi_msi_ops = {
+};
+
+static struct msi_domain_info odmi_msi_domain_info = {
+ .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS),
+ .ops = &odmi_msi_ops,
+ .chip = &odmi_msi_irq_chip,
+};
+
+static int __init mvebu_odmi_init(struct device_node *node,
+ struct device_node *parent)
+{
+ struct irq_domain *inner_domain, *plat_domain;
+ int ret, i;
+
+ if (of_property_read_u32(node, "marvell,odmi-frames", &odmis_count))
+ return -EINVAL;
+
+ odmis = kcalloc(odmis_count, sizeof(struct odmi_data), GFP_KERNEL);
+ if (!odmis)
+ return -ENOMEM;
+
+ for (i = 0; i < odmis_count; i++) {
+ struct odmi_data *odmi = &odmis[i];
+
+ ret = of_address_to_resource(node, i, &odmi->res);
+ if (ret)
+ goto err_unmap;
+
+ odmi->base = of_io_request_and_map(node, i, "odmi");
+ if (IS_ERR(odmi->base)) {
+ ret = PTR_ERR(odmi->base);
+ goto err_unmap;
+ }
+
+ if (of_property_read_u32_index(node, "marvell,spi-base",
+ i, &odmi->spi_base)) {
+ ret = -EINVAL;
+ goto err_unmap;
+ }
+ }
+
+ inner_domain = irq_domain_create_linear(of_node_to_fwnode(node),
+ odmis_count * NODMIS_PER_FRAME,
+ &odmi_domain_ops, NULL);
+ if (!inner_domain) {
+ ret = -ENOMEM;
+ goto err_unmap;
+ }
+
+ inner_domain->parent = irq_find_host(parent);
+
+ plat_domain = platform_msi_create_irq_domain(of_node_to_fwnode(node),
+ &odmi_msi_domain_info,
+ inner_domain);
+ if (!plat_domain) {
+ ret = -ENOMEM;
+ goto err_remove_inner;
+ }
+
+ return 0;
+
+err_remove_inner:
+ irq_domain_remove(inner_domain);
+err_unmap:
+ for (i = 0; i < odmis_count; i++) {
+ struct odmi_data *odmi = &odmis[i];
+
+ if (odmi->base && !IS_ERR(odmi->base))
+ iounmap(odmis[i].base);
+ }
+ kfree(odmis);
+ return ret;
+}
+
+IRQCHIP_DECLARE(mvebu_odmi, "marvell,odmi-controller", mvebu_odmi_init);
--
2.6.4