--- /dev/null
+/*
+ * Copyright (C) 2014-2015 Toradex AG
+ * Author: Stefan Agner <stefan@agner.ch>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ *
+ * IRQ chip driver for MSCM interrupt router available on Vybrid SoC's.
+ * The interrupt router is between the CPU's interrupt controller and the
+ * peripheral. The router allows to route the peripheral interrupts to
+ * one of the two available CPU's on Vybrid VF6xx SoC's (Cortex-A5 or
+ * Cortex-M4). The router will be configured transparently on a IRQ
+ * request.
+ *
+ * o All peripheral interrupts of the Vybrid SoC can be routed to
+ * CPU 0, CPU 1 or both. The routing is useful for dual-core
+ * variants of Vybrid SoC such as VF6xx. This driver routes the
+ * requested interrupt to the CPU currently running on.
+ *
+ * o It is required to setup the interrupt router even on single-core
+ * variants of Vybrid.
+ */
+
+#include <linux/cpu_pm.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/mfd/syscon.h>
+#include <dt-bindings/interrupt-controller/arm-gic.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/slab.h>
+#include <linux/regmap.h>
+
+#include "irqchip.h"
+
+#define MSCM_CPxNUM 0x4
+
+#define MSCM_IRSPRC(n) (0x80 + 2 * (n))
+#define MSCM_IRSPRC_CPEN_MASK 0x3
+
+#define MSCM_IRSPRC_NUM 112
+
+struct vf610_mscm_ir_chip_data {
+ void __iomem *mscm_ir_base;
+ u16 cpu_mask;
+ u16 saved_irsprc[MSCM_IRSPRC_NUM];
+};
+
+static struct vf610_mscm_ir_chip_data *mscm_ir_data;
+
+static inline void vf610_mscm_ir_save(struct vf610_mscm_ir_chip_data *data)
+{
+ int i;
+
+ for (i = 0; i < MSCM_IRSPRC_NUM; i++)
+ data->saved_irsprc[i] = readw_relaxed(data->mscm_ir_base + MSCM_IRSPRC(i));
+}
+
+static inline void vf610_mscm_ir_restore(struct vf610_mscm_ir_chip_data *data)
+{
+ int i;
+
+ for (i = 0; i < MSCM_IRSPRC_NUM; i++)
+ writew_relaxed(data->saved_irsprc[i], data->mscm_ir_base + MSCM_IRSPRC(i));
+}
+
+static int vf610_mscm_ir_notifier(struct notifier_block *self,
+ unsigned long cmd, void *v)
+{
+ switch (cmd) {
+ case CPU_CLUSTER_PM_ENTER:
+ vf610_mscm_ir_save(mscm_ir_data);
+ break;
+ case CPU_CLUSTER_PM_ENTER_FAILED:
+ case CPU_CLUSTER_PM_EXIT:
+ vf610_mscm_ir_restore(mscm_ir_data);
+ break;
+ }
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block mscm_ir_notifier_block = {
+ .notifier_call = vf610_mscm_ir_notifier,
+};
+
+static void vf610_mscm_ir_enable(struct irq_data *data)
+{
+ irq_hw_number_t hwirq = data->hwirq;
+ struct vf610_mscm_ir_chip_data *chip_data = data->chip_data;
+ u16 irsprc;
+
+ irsprc = readw_relaxed(chip_data->mscm_ir_base + MSCM_IRSPRC(hwirq));
+ irsprc &= MSCM_IRSPRC_CPEN_MASK;
+
+ WARN_ON(irsprc & ~chip_data->cpu_mask);
+
+ writew_relaxed(chip_data->cpu_mask,
+ chip_data->mscm_ir_base + MSCM_IRSPRC(hwirq));
+
+ irq_chip_unmask_parent(data);
+}
+
+static void vf610_mscm_ir_disable(struct irq_data *data)
+{
+ irq_hw_number_t hwirq = data->hwirq;
+ struct vf610_mscm_ir_chip_data *chip_data = data->chip_data;
+
+ writew_relaxed(0x0, chip_data->mscm_ir_base + MSCM_IRSPRC(hwirq));
+
+ irq_chip_mask_parent(data);
+}
+
+static struct irq_chip vf610_mscm_ir_irq_chip = {
+ .name = "mscm-ir",
+ .irq_mask = irq_chip_mask_parent,
+ .irq_unmask = irq_chip_unmask_parent,
+ .irq_eoi = irq_chip_eoi_parent,
+ .irq_enable = vf610_mscm_ir_enable,
+ .irq_disable = vf610_mscm_ir_disable,
+ .irq_retrigger = irq_chip_retrigger_hierarchy,
+ .irq_set_affinity = irq_chip_set_affinity_parent,
+};
+
+static int vf610_mscm_ir_domain_alloc(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs, void *arg)
+{
+ int i;
+ irq_hw_number_t hwirq;
+ struct of_phandle_args *irq_data = arg;
+ struct of_phandle_args gic_data;
+
+ if (irq_data->args_count != 2)
+ return -EINVAL;
+
+ hwirq = irq_data->args[0];
+ for (i = 0; i < nr_irqs; i++)
+ irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
+ &vf610_mscm_ir_irq_chip,
+ domain->host_data);
+
+ gic_data.np = domain->parent->of_node;
+ gic_data.args_count = 3;
+ gic_data.args[0] = GIC_SPI;
+ gic_data.args[1] = irq_data->args[0];
+ gic_data.args[2] = irq_data->args[1];
+ return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &gic_data);
+}
+
+static const struct irq_domain_ops mscm_irq_domain_ops = {
+ .xlate = irq_domain_xlate_twocell,
+ .alloc = vf610_mscm_ir_domain_alloc,
+ .free = irq_domain_free_irqs_common,
+};
+
+static int __init vf610_mscm_ir_of_init(struct device_node *node,
+ struct device_node *parent)
+{
+ struct irq_domain *domain, *domain_parent;
+ struct regmap *mscm_cp_regmap;
+ int ret, cpuid;
+
+ domain_parent = irq_find_host(parent);
+ if (!domain_parent) {
+ pr_err("vf610_mscm_ir: interrupt-parent not found\n");
+ return -EINVAL;
+ }
+
+ mscm_ir_data = kzalloc(sizeof(*mscm_ir_data), GFP_KERNEL);
+ if (!mscm_ir_data)
+ return -ENOMEM;
+
+ mscm_ir_data->mscm_ir_base = of_io_request_and_map(node, 0, "mscm-ir");
+
+ if (!mscm_ir_data->mscm_ir_base) {
+ pr_err("vf610_mscm_ir: unable to map mscm register\n");
+ ret = -ENOMEM;
+ goto out_free;
+ }
+
+ mscm_cp_regmap = syscon_regmap_lookup_by_phandle(node, "fsl,cpucfg");
+ if (IS_ERR(mscm_cp_regmap)) {
+ ret = PTR_ERR(mscm_cp_regmap);
+ pr_err("vf610_mscm_ir: regmap lookup for cpucfg failed\n");
+ goto out_unmap;
+ }
+
+ regmap_read(mscm_cp_regmap, MSCM_CPxNUM, &cpuid);
+ mscm_ir_data->cpu_mask = 0x1 << cpuid;
+
+ domain = irq_domain_add_hierarchy(domain_parent, 0,
+ MSCM_IRSPRC_NUM, node,
+ &mscm_irq_domain_ops, mscm_ir_data);
+ if (!domain) {
+ ret = -ENOMEM;
+ goto out_unmap;
+ }
+
+ cpu_pm_register_notifier(&mscm_ir_notifier_block);
+
+ return 0;
+
+out_unmap:
+ iounmap(mscm_ir_data->mscm_ir_base);
+out_free:
+ kfree(mscm_ir_data);
+ return ret;
+}
+IRQCHIP_DECLARE(vf610_mscm_ir, "fsl,vf610-mscm-ir", vf610_mscm_ir_of_init);
projects / platform / kernel / linux-rpi.git / commitdiff