drivers/irqchip/irq-mvebu-gicp.c

   1 /*
   2  * Copyright (C) 2017 Marvell
   3  *
   4  * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
   5  *
   6  * This file is licensed under the terms of the GNU General Public
   7  * License version 2. This program is licensed "as is" without any
   8  * warranty of any kind, whether express or implied.
   9  */
  10
  11 #include <linux/io.h>
  12 #include <linux/irq.h>
  13 #include <linux/irqdomain.h>
  14 #include <linux/msi.h>
  15 #include <linux/of.h>
  16 #include <linux/of_irq.h>
  17 #include <linux/of_platform.h>
  18 #include <linux/platform_device.h>
  19
  20 #include <dt-bindings/interrupt-controller/arm-gic.h>
  21
  22 #include "irq-mvebu-gicp.h"
  23
  24 #define GICP_SETSPI_NSR_OFFSET  0x0
  25 #define GICP_CLRSPI_NSR_OFFSET  0x8
  26
  27 struct mvebu_gicp_spi_range {
  28         unsigned int start;
  29         unsigned int count;
  30 };
  31
  32 struct mvebu_gicp {
  33         struct mvebu_gicp_spi_range *spi_ranges;
  34         unsigned int spi_ranges_cnt;
  35         unsigned int spi_cnt;
  36         unsigned long *spi_bitmap;
  37         spinlock_t spi_lock;
  38         struct resource *res;
  39         struct device *dev;
  40 };
  41
  42 static int gicp_idx_to_spi(struct mvebu_gicp *gicp, int idx)
  43 {
  44         int i;
  45
  46         for (i = 0; i < gicp->spi_ranges_cnt; i++) {
  47                 struct mvebu_gicp_spi_range *r = &gicp->spi_ranges[i];
  48
  49                 if (idx < r->count)
  50                         return r->start + idx;
  51
  52                 idx -= r->count;
  53         }
  54
  55         return -EINVAL;
  56 }
  57
  58 int mvebu_gicp_get_doorbells(struct device_node *dn, phys_addr_t *setspi,
  59                              phys_addr_t *clrspi)
  60 {
  61         struct platform_device *pdev;
  62         struct mvebu_gicp *gicp;
  63
  64         pdev = of_find_device_by_node(dn);
  65         if (!pdev)
  66                 return -ENODEV;
  67
  68         gicp = platform_get_drvdata(pdev);
  69         if (!gicp)
  70                 return -ENODEV;
  71
  72         *setspi = gicp->res->start + GICP_SETSPI_NSR_OFFSET;
  73         *clrspi = gicp->res->start + GICP_CLRSPI_NSR_OFFSET;
  74
  75         return 0;
  76 }
  77
  78 static void gicp_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
  79 {
  80         struct mvebu_gicp *gicp = data->chip_data;
  81         phys_addr_t setspi = gicp->res->start + GICP_SETSPI_NSR_OFFSET;
  82
  83         msg->data = data->hwirq;
  84         msg->address_lo = lower_32_bits(setspi);
  85         msg->address_hi = upper_32_bits(setspi);
  86 }
  87
  88 static struct irq_chip gicp_irq_chip = {
  89         .name                   = "GICP",
  90         .irq_mask               = irq_chip_mask_parent,
  91         .irq_unmask             = irq_chip_unmask_parent,
  92         .irq_eoi                = irq_chip_eoi_parent,
  93         .irq_set_affinity       = irq_chip_set_affinity_parent,
  94         .irq_set_type           = irq_chip_set_type_parent,
  95         .irq_compose_msi_msg    = gicp_compose_msi_msg,
  96 };
  97
  98 static int gicp_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
  99                                  unsigned int nr_irqs, void *args)
 100 {
 101         struct mvebu_gicp *gicp = domain->host_data;
 102         struct irq_fwspec fwspec;
 103         unsigned int hwirq;
 104         int ret;
 105
 106         spin_lock(&gicp->spi_lock);
 107         hwirq = find_first_zero_bit(gicp->spi_bitmap, gicp->spi_cnt);
 108         if (hwirq == gicp->spi_cnt) {
 109                 spin_unlock(&gicp->spi_lock);
 110                 return -ENOSPC;
 111         }
 112         __set_bit(hwirq, gicp->spi_bitmap);
 113         spin_unlock(&gicp->spi_lock);
 114
 115         fwspec.fwnode = domain->parent->fwnode;
 116         fwspec.param_count = 3;
 117         fwspec.param[0] = GIC_SPI;
 118         fwspec.param[1] = gicp_idx_to_spi(gicp, hwirq) - 32;
 119         /*
 120          * Assume edge rising for now, it will be properly set when
 121          * ->set_type() is called
 122          */
 123         fwspec.param[2] = IRQ_TYPE_EDGE_RISING;
 124
 125         ret = irq_domain_alloc_irqs_parent(domain, virq, 1, &fwspec);
 126         if (ret) {
 127                 dev_err(gicp->dev, "Cannot allocate parent IRQ\n");
 128                 goto free_hwirq;
 129         }
 130
 131         ret = irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
 132                                             &gicp_irq_chip, gicp);
 133         if (ret)
 134                 goto free_irqs_parent;
 135
 136         return 0;
 137
 138 free_irqs_parent:
 139         irq_domain_free_irqs_parent(domain, virq, nr_irqs);
 140 free_hwirq:
 141         spin_lock(&gicp->spi_lock);
 142         __clear_bit(hwirq, gicp->spi_bitmap);
 143         spin_unlock(&gicp->spi_lock);
 144         return ret;
 145 }
 146
 147 static void gicp_irq_domain_free(struct irq_domain *domain,
 148                                  unsigned int virq, unsigned int nr_irqs)
 149 {
 150         struct mvebu_gicp *gicp = domain->host_data;
 151         struct irq_data *d = irq_domain_get_irq_data(domain, virq);
 152
 153         if (d->hwirq >= gicp->spi_cnt) {
 154                 dev_err(gicp->dev, "Invalid hwirq %lu\n", d->hwirq);
 155                 return;
 156         }
 157
 158         irq_domain_free_irqs_parent(domain, virq, nr_irqs);
 159
 160         spin_lock(&gicp->spi_lock);
 161         __clear_bit(d->hwirq, gicp->spi_bitmap);
 162         spin_unlock(&gicp->spi_lock);
 163 }
 164
 165 static const struct irq_domain_ops gicp_domain_ops = {
 166         .alloc  = gicp_irq_domain_alloc,
 167         .free   = gicp_irq_domain_free,
 168 };
 169
 170 static struct irq_chip gicp_msi_irq_chip = {
 171         .name           = "GICP",
 172         .irq_set_type   = irq_chip_set_type_parent,
 173 };
 174
 175 static struct msi_domain_ops gicp_msi_ops = {
 176 };
 177
 178 static struct msi_domain_info gicp_msi_domain_info = {
 179         .flags  = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS),
 180         .ops    = &gicp_msi_ops,
 181         .chip   = &gicp_msi_irq_chip,
 182 };
 183
 184 static int mvebu_gicp_probe(struct platform_device *pdev)
 185 {
 186         struct mvebu_gicp *gicp;
 187         struct irq_domain *inner_domain, *plat_domain, *parent_domain;
 188         struct device_node *node = pdev->dev.of_node;
 189         struct device_node *irq_parent_dn;
 190         int ret, i;
 191
 192         gicp = devm_kzalloc(&pdev->dev, sizeof(*gicp), GFP_KERNEL);
 193         if (!gicp)
 194                 return -ENOMEM;
 195
 196         gicp->dev = &pdev->dev;
 197
 198         gicp->res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 199         if (!gicp->res)
 200                 return -ENODEV;
 201
 202         ret = of_property_count_u32_elems(node, "marvell,spi-ranges");
 203         if (ret < 0)
 204                 return ret;
 205
 206         gicp->spi_ranges_cnt = ret / 2;
 207
 208         gicp->spi_ranges =
 209                 devm_kzalloc(&pdev->dev,
 210                              gicp->spi_ranges_cnt *
 211                              sizeof(struct mvebu_gicp_spi_range),
 212                              GFP_KERNEL);
 213         if (!gicp->spi_ranges)
 214                 return -ENOMEM;
 215
 216         for (i = 0; i < gicp->spi_ranges_cnt; i++) {
 217                 of_property_read_u32_index(node, "marvell,spi-ranges",
 218                                            i * 2,
 219                                            &gicp->spi_ranges[i].start);
 220
 221                 of_property_read_u32_index(node, "marvell,spi-ranges",
 222                                            i * 2 + 1,
 223                                            &gicp->spi_ranges[i].count);
 224
 225                 gicp->spi_cnt += gicp->spi_ranges[i].count;
 226         }
 227
 228         gicp->spi_bitmap = devm_kzalloc(&pdev->dev,
 229                                 BITS_TO_LONGS(gicp->spi_cnt) * sizeof(long),
 230                                 GFP_KERNEL);
 231         if (!gicp->spi_bitmap)
 232                 return -ENOMEM;
 233
 234         irq_parent_dn = of_irq_find_parent(node);
 235         if (!irq_parent_dn) {
 236                 dev_err(&pdev->dev, "failed to find parent IRQ node\n");
 237                 return -ENODEV;
 238         }
 239
 240         parent_domain = irq_find_host(irq_parent_dn);
 241         if (!parent_domain) {
 242                 dev_err(&pdev->dev, "failed to find parent IRQ domain\n");
 243                 return -ENODEV;
 244         }
 245
 246         inner_domain = irq_domain_create_hierarchy(parent_domain, 0,
 247                                                    gicp->spi_cnt,
 248                                                    of_node_to_fwnode(node),
 249                                                    &gicp_domain_ops, gicp);
 250         if (!inner_domain)
 251                 return -ENOMEM;
 252
 253
 254         plat_domain = platform_msi_create_irq_domain(of_node_to_fwnode(node),
 255                                                      &gicp_msi_domain_info,
 256                                                      inner_domain);
 257         if (!plat_domain) {
 258                 irq_domain_remove(inner_domain);
 259                 return -ENOMEM;
 260         }
 261
 262         platform_set_drvdata(pdev, gicp);
 263
 264         return 0;
 265 }
 266
 267 static const struct of_device_id mvebu_gicp_of_match[] = {
 268         { .compatible = "marvell,ap806-gicp", },
 269         {},
 270 };
 271
 272 static struct platform_driver mvebu_gicp_driver = {
 273         .probe  = mvebu_gicp_probe,
 274         .driver = {
 275                 .name = "mvebu-gicp",
 276                 .of_match_table = mvebu_gicp_of_match,
 277         },
 278 };
 279 builtin_platform_driver(mvebu_gicp_driver);