--- /dev/null
+/*
+ * ARM GIC v2m MSI(-X) support
+ * Support for Message Signaled Interrupts for systems that
+ * implement ARM Generic Interrupt Controller: GICv2m.
+ *
+ * Copyright (C) 2014 Advanced Micro Devices, Inc.
+ * Authors: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
+ * Harish Kasiviswanathan <harish.kasiviswanathan@amd.com>
+ * Brandon Anderson <brandon.anderson@amd.com>
+ *
+ * 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.
+ */
+
+#define pr_fmt(fmt) "GICv2m: " fmt
+
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/kernel.h>
+#include <linux/of_address.h>
+#include <linux/of_pci.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+/*
+* MSI_TYPER:
+* [31:26] Reserved
+* [25:16] lowest SPI assigned to MSI
+* [15:10] Reserved
+* [9:0] Numer of SPIs assigned to MSI
+*/
+#define V2M_MSI_TYPER 0x008
+#define V2M_MSI_TYPER_BASE_SHIFT 16
+#define V2M_MSI_TYPER_BASE_MASK 0x3FF
+#define V2M_MSI_TYPER_NUM_MASK 0x3FF
+#define V2M_MSI_SETSPI_NS 0x040
+#define V2M_MIN_SPI 32
+#define V2M_MAX_SPI 1019
+
+#define V2M_MSI_TYPER_BASE_SPI(x) \
+ (((x) >> V2M_MSI_TYPER_BASE_SHIFT) & V2M_MSI_TYPER_BASE_MASK)
+
+#define V2M_MSI_TYPER_NUM_SPI(x) ((x) & V2M_MSI_TYPER_NUM_MASK)
+
+struct v2m_data {
+ spinlock_t msi_cnt_lock;
+ struct msi_controller mchip;
+ struct resource res; /* GICv2m resource */
+ void __iomem *base; /* GICv2m virt address */
+ u32 spi_start; /* The SPI number that MSIs start */
+ u32 nr_spis; /* The number of SPIs for MSIs */
+ unsigned long *bm; /* MSI vector bitmap */
+ struct irq_domain *domain;
+};
+
+static void gicv2m_mask_msi_irq(struct irq_data *d)
+{
+ pci_msi_mask_irq(d);
+ irq_chip_mask_parent(d);
+}
+
+static void gicv2m_unmask_msi_irq(struct irq_data *d)
+{
+ pci_msi_unmask_irq(d);
+ irq_chip_unmask_parent(d);
+}
+
+static struct irq_chip gicv2m_msi_irq_chip = {
+ .name = "MSI",
+ .irq_mask = gicv2m_mask_msi_irq,
+ .irq_unmask = gicv2m_unmask_msi_irq,
+ .irq_eoi = irq_chip_eoi_parent,
+ .irq_write_msi_msg = pci_msi_domain_write_msg,
+};
+
+static struct msi_domain_info gicv2m_msi_domain_info = {
+ .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
+ MSI_FLAG_PCI_MSIX),
+ .chip = &gicv2m_msi_irq_chip,
+};
+
+static int gicv2m_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 gicv2m_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
+{
+ struct v2m_data *v2m = irq_data_get_irq_chip_data(data);
+ phys_addr_t addr = v2m->res.start + V2M_MSI_SETSPI_NS;
+
+ msg->address_hi = (u32) (addr >> 32);
+ msg->address_lo = (u32) (addr);
+ msg->data = data->hwirq;
+}
+
+static struct irq_chip gicv2m_irq_chip = {
+ .name = "GICv2m",
+ .irq_mask = irq_chip_mask_parent,
+ .irq_unmask = irq_chip_unmask_parent,
+ .irq_eoi = irq_chip_eoi_parent,
+ .irq_set_affinity = gicv2m_set_affinity,
+ .irq_compose_msi_msg = gicv2m_compose_msi_msg,
+};
+
+static int gicv2m_irq_gic_domain_alloc(struct irq_domain *domain,
+ unsigned int virq,
+ irq_hw_number_t hwirq)
+{
+ struct of_phandle_args args;
+ struct irq_data *d;
+ int err;
+
+ args.np = domain->parent->of_node;
+ args.args_count = 3;
+ args.args[0] = 0;
+ args.args[1] = hwirq - 32;
+ args.args[2] = IRQ_TYPE_EDGE_RISING;
+
+ err = irq_domain_alloc_irqs_parent(domain, virq, 1, &args);
+ if (err)
+ return err;
+
+ /* 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);
+ return 0;
+}
+
+static void gicv2m_unalloc_msi(struct v2m_data *v2m, unsigned int hwirq)
+{
+ int pos;
+
+ pos = hwirq - v2m->spi_start;
+ if (pos < 0 || pos >= v2m->nr_spis) {
+ pr_err("Failed to teardown msi. Invalid hwirq %d\n", hwirq);
+ return;
+ }
+
+ spin_lock(&v2m->msi_cnt_lock);
+ __clear_bit(pos, v2m->bm);
+ spin_unlock(&v2m->msi_cnt_lock);
+}
+
+static int gicv2m_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs, void *args)
+{
+ struct v2m_data *v2m = domain->host_data;
+ int hwirq, offset, err = 0;
+
+ spin_lock(&v2m->msi_cnt_lock);
+ offset = find_first_zero_bit(v2m->bm, v2m->nr_spis);
+ if (offset < v2m->nr_spis)
+ __set_bit(offset, v2m->bm);
+ else
+ err = -ENOSPC;
+ spin_unlock(&v2m->msi_cnt_lock);
+
+ if (err)
+ return err;
+
+ hwirq = v2m->spi_start + offset;
+
+ err = gicv2m_irq_gic_domain_alloc(domain, virq, hwirq);
+ if (err) {
+ gicv2m_unalloc_msi(v2m, hwirq);
+ return err;
+ }
+
+ irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
+ &gicv2m_irq_chip, v2m);
+
+ return 0;
+}
+
+static void gicv2m_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 v2m_data *v2m = irq_data_get_irq_chip_data(d);
+
+ BUG_ON(nr_irqs != 1);
+ gicv2m_unalloc_msi(v2m, d->hwirq);
+ irq_domain_free_irqs_parent(domain, virq, nr_irqs);
+}
+
+static const struct irq_domain_ops gicv2m_domain_ops = {
+ .alloc = gicv2m_irq_domain_alloc,
+ .free = gicv2m_irq_domain_free,
+};
+
+static bool is_msi_spi_valid(u32 base, u32 num)
+{
+ if (base < V2M_MIN_SPI) {
+ pr_err("Invalid MSI base SPI (base:%u)\n", base);
+ return false;
+ }
+
+ if ((num == 0) || (base + num > V2M_MAX_SPI)) {
+ pr_err("Number of SPIs (%u) exceed maximum (%u)\n",
+ num, V2M_MAX_SPI - V2M_MIN_SPI + 1);
+ return false;
+ }
+
+ return true;
+}
+
+static int __init gicv2m_init_one(struct device_node *node,
+ struct irq_domain *parent)
+{
+ int ret;
+ struct v2m_data *v2m;
+
+ v2m = kzalloc(sizeof(struct v2m_data), GFP_KERNEL);
+ if (!v2m) {
+ pr_err("Failed to allocate struct v2m_data.\n");
+ return -ENOMEM;
+ }
+
+ ret = of_address_to_resource(node, 0, &v2m->res);
+ if (ret) {
+ pr_err("Failed to allocate v2m resource.\n");
+ goto err_free_v2m;
+ }
+
+ v2m->base = ioremap(v2m->res.start, resource_size(&v2m->res));
+ if (!v2m->base) {
+ pr_err("Failed to map GICv2m resource\n");
+ ret = -ENOMEM;
+ goto err_free_v2m;
+ }
+
+ if (!of_property_read_u32(node, "arm,msi-base-spi", &v2m->spi_start) &&
+ !of_property_read_u32(node, "arm,msi-num-spis", &v2m->nr_spis)) {
+ pr_info("Overriding V2M MSI_TYPER (base:%u, num:%u)\n",
+ v2m->spi_start, v2m->nr_spis);
+ } else {
+ u32 typer = readl_relaxed(v2m->base + V2M_MSI_TYPER);
+
+ v2m->spi_start = V2M_MSI_TYPER_BASE_SPI(typer);
+ v2m->nr_spis = V2M_MSI_TYPER_NUM_SPI(typer);
+ }
+
+ if (!is_msi_spi_valid(v2m->spi_start, v2m->nr_spis)) {
+ ret = -EINVAL;
+ goto err_iounmap;
+ }
+
+ v2m->bm = kzalloc(sizeof(long) * BITS_TO_LONGS(v2m->nr_spis),
+ GFP_KERNEL);
+ if (!v2m->bm) {
+ ret = -ENOMEM;
+ goto err_iounmap;
+ }
+
+ v2m->domain = irq_domain_add_tree(NULL, &gicv2m_domain_ops, v2m);
+ if (!v2m->domain) {
+ pr_err("Failed to create GICv2m domain\n");
+ ret = -ENOMEM;
+ goto err_free_bm;
+ }
+
+ v2m->domain->parent = parent;
+ v2m->mchip.of_node = node;
+ v2m->mchip.domain = pci_msi_create_irq_domain(node,
+ &gicv2m_msi_domain_info,
+ v2m->domain);
+ if (!v2m->mchip.domain) {
+ pr_err("Failed to create MSI domain\n");
+ ret = -ENOMEM;
+ goto err_free_domains;
+ }
+
+ spin_lock_init(&v2m->msi_cnt_lock);
+
+ ret = of_pci_msi_chip_add(&v2m->mchip);
+ if (ret) {
+ pr_err("Failed to add msi_chip.\n");
+ goto err_free_domains;
+ }
+
+ pr_info("Node %s: range[%#lx:%#lx], SPI[%d:%d]\n", node->name,
+ (unsigned long)v2m->res.start, (unsigned long)v2m->res.end,
+ v2m->spi_start, (v2m->spi_start + v2m->nr_spis));
+
+ return 0;
+
+err_free_domains:
+ if (v2m->mchip.domain)
+ irq_domain_remove(v2m->mchip.domain);
+ if (v2m->domain)
+ irq_domain_remove(v2m->domain);
+err_free_bm:
+ kfree(v2m->bm);
+err_iounmap:
+ iounmap(v2m->base);
+err_free_v2m:
+ kfree(v2m);
+ return ret;
+}
+
+static struct of_device_id gicv2m_device_id[] = {
+ { .compatible = "arm,gic-v2m-frame", },
+ {},
+};
+
+int __init gicv2m_of_init(struct device_node *node, struct irq_domain *parent)
+{
+ int ret = 0;
+ struct device_node *child;
+
+ for (child = of_find_matching_node(node, gicv2m_device_id); child;
+ child = of_find_matching_node(child, gicv2m_device_id)) {
+ if (!of_find_property(child, "msi-controller", NULL))
+ continue;
+
+ ret = gicv2m_init_one(child, parent);
+ if (ret) {
+ of_node_put(node);
+ break;
+ }
+ }
+
+ return ret;
+}
projects / firefly-linux-kernel-4.4.55.git / commitdiff