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 "irq-msi-lib.h"
  21
  22 #include <dt-bindings/interrupt-controller/arm-gic.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 static void gicp_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
  59 {
  60         struct mvebu_gicp *gicp = data->chip_data;
  61         phys_addr_t setspi = gicp->res->start + GICP_SETSPI_NSR_OFFSET;
  62         phys_addr_t clrspi = gicp->res->start + GICP_CLRSPI_NSR_OFFSET;
  63
  64         msg[0].data = data->hwirq;
  65         msg[0].address_lo = lower_32_bits(setspi);
  66         msg[0].address_hi = upper_32_bits(setspi);
  67         msg[1].data = data->hwirq;
  68         msg[1].address_lo = lower_32_bits(clrspi);
  69         msg[1].address_hi = upper_32_bits(clrspi);
  70 }
  71
  72 static struct irq_chip gicp_irq_chip = {
  73         .name                   = "GICP",
  74         .irq_mask               = irq_chip_mask_parent,
  75         .irq_unmask             = irq_chip_unmask_parent,
  76         .irq_eoi                = irq_chip_eoi_parent,
  77         .irq_set_affinity       = irq_chip_set_affinity_parent,
  78         .irq_set_type           = irq_chip_set_type_parent,
  79         .irq_compose_msi_msg    = gicp_compose_msi_msg,
  80 };
  81
  82 static int gicp_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
  83                                  unsigned int nr_irqs, void *args)
  84 {
  85         struct mvebu_gicp *gicp = domain->host_data;
  86         struct irq_fwspec fwspec;
  87         unsigned int hwirq;
  88         int ret;
  89
  90         spin_lock(&gicp->spi_lock);
  91         hwirq = find_first_zero_bit(gicp->spi_bitmap, gicp->spi_cnt);
  92         if (hwirq == gicp->spi_cnt) {
  93                 spin_unlock(&gicp->spi_lock);
  94                 return -ENOSPC;
  95         }
  96         __set_bit(hwirq, gicp->spi_bitmap);
  97         spin_unlock(&gicp->spi_lock);
  98
  99         fwspec.fwnode = domain->parent->fwnode;
 100         fwspec.param_count = 3;
 101         fwspec.param[0] = GIC_SPI;
 102         fwspec.param[1] = gicp_idx_to_spi(gicp, hwirq) - 32;
 103         /*
 104          * Assume edge rising for now, it will be properly set when
 105          * ->set_type() is called
 106          */
 107         fwspec.param[2] = IRQ_TYPE_EDGE_RISING;
 108
 109         ret = irq_domain_alloc_irqs_parent(domain, virq, 1, &fwspec);
 110         if (ret) {
 111                 dev_err(gicp->dev, "Cannot allocate parent IRQ\n");
 112                 goto free_hwirq;
 113         }
 114
 115         ret = irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
 116                                             &gicp_irq_chip, gicp);
 117         if (ret)
 118                 goto free_irqs_parent;
 119
 120         return 0;
 121
 122 free_irqs_parent:
 123         irq_domain_free_irqs_parent(domain, virq, nr_irqs);
 124 free_hwirq:
 125         spin_lock(&gicp->spi_lock);
 126         __clear_bit(hwirq, gicp->spi_bitmap);
 127         spin_unlock(&gicp->spi_lock);
 128         return ret;
 129 }
 130
 131 static void gicp_irq_domain_free(struct irq_domain *domain,
 132                                  unsigned int virq, unsigned int nr_irqs)
 133 {
 134         struct mvebu_gicp *gicp = domain->host_data;
 135         struct irq_data *d = irq_domain_get_irq_data(domain, virq);
 136
 137         if (d->hwirq >= gicp->spi_cnt) {
 138                 dev_err(gicp->dev, "Invalid hwirq %lu\n", d->hwirq);
 139                 return;
 140         }
 141
 142         irq_domain_free_irqs_parent(domain, virq, nr_irqs);
 143
 144         spin_lock(&gicp->spi_lock);
 145         __clear_bit(d->hwirq, gicp->spi_bitmap);
 146         spin_unlock(&gicp->spi_lock);
 147 }
 148
 149 static const struct irq_domain_ops gicp_domain_ops = {
 150         .select = msi_lib_irq_domain_select,
 151         .alloc  = gicp_irq_domain_alloc,
 152         .free   = gicp_irq_domain_free,
 153 };
 154
 155 #define GICP_MSI_FLAGS_REQUIRED  (MSI_FLAG_USE_DEF_DOM_OPS |    \
 156                                   MSI_FLAG_USE_DEF_CHIP_OPS)
 157
 158 #define GICP_MSI_FLAGS_SUPPORTED (MSI_GENERIC_FLAGS_MASK |      \
 159                                   MSI_FLAG_LEVEL_CAPABLE)
 160
 161 static const struct msi_parent_ops gicp_msi_parent_ops = {
 162         .supported_flags        = GICP_MSI_FLAGS_SUPPORTED,
 163         .required_flags         = GICP_MSI_FLAGS_REQUIRED,
 164         .bus_select_token       = DOMAIN_BUS_GENERIC_MSI,
 165         .bus_select_mask        = MATCH_PLATFORM_MSI,
 166         .prefix                 = "GICP-",
 167         .init_dev_msi_info      = msi_lib_init_dev_msi_info,
 168 };
 169
 170 static int mvebu_gicp_probe(struct platform_device *pdev)
 171 {
 172         struct irq_domain *inner_domain, *parent_domain;
 173         struct device_node *node = pdev->dev.of_node;
 174         struct device_node *irq_parent_dn;
 175         struct mvebu_gicp *gicp;
 176         int ret, i;
 177
 178         gicp = devm_kzalloc(&pdev->dev, sizeof(*gicp), GFP_KERNEL);
 179         if (!gicp)
 180                 return -ENOMEM;
 181
 182         gicp->dev = &pdev->dev;
 183         spin_lock_init(&gicp->spi_lock);
 184
 185         gicp->res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 186         if (!gicp->res)
 187                 return -ENODEV;
 188
 189         ret = of_property_count_u32_elems(node, "marvell,spi-ranges");
 190         if (ret < 0)
 191                 return ret;
 192
 193         gicp->spi_ranges_cnt = ret / 2;
 194
 195         gicp->spi_ranges =
 196                 devm_kcalloc(&pdev->dev,
 197                              gicp->spi_ranges_cnt,
 198                              sizeof(struct mvebu_gicp_spi_range),
 199                              GFP_KERNEL);
 200         if (!gicp->spi_ranges)
 201                 return -ENOMEM;
 202
 203         for (i = 0; i < gicp->spi_ranges_cnt; i++) {
 204                 of_property_read_u32_index(node, "marvell,spi-ranges",
 205                                            i * 2,
 206                                            &gicp->spi_ranges[i].start);
 207
 208                 of_property_read_u32_index(node, "marvell,spi-ranges",
 209                                            i * 2 + 1,
 210                                            &gicp->spi_ranges[i].count);
 211
 212                 gicp->spi_cnt += gicp->spi_ranges[i].count;
 213         }
 214
 215         gicp->spi_bitmap = devm_bitmap_zalloc(&pdev->dev, gicp->spi_cnt, GFP_KERNEL);
 216         if (!gicp->spi_bitmap)
 217                 return -ENOMEM;
 218
 219         irq_parent_dn = of_irq_find_parent(node);
 220         if (!irq_parent_dn) {
 221                 dev_err(&pdev->dev, "failed to find parent IRQ node\n");
 222                 return -ENODEV;
 223         }
 224
 225         parent_domain = irq_find_host(irq_parent_dn);
 226         of_node_put(irq_parent_dn);
 227         if (!parent_domain) {
 228                 dev_err(&pdev->dev, "failed to find parent IRQ domain\n");
 229                 return -ENODEV;
 230         }
 231
 232         inner_domain = irq_domain_create_hierarchy(parent_domain, 0,
 233                                                    gicp->spi_cnt,
 234                                                    of_node_to_fwnode(node),
 235                                                    &gicp_domain_ops, gicp);
 236         if (!inner_domain)
 237                 return -ENOMEM;
 238
 239         irq_domain_update_bus_token(inner_domain, DOMAIN_BUS_GENERIC_MSI);
 240         inner_domain->flags |= IRQ_DOMAIN_FLAG_MSI_PARENT;
 241         inner_domain->msi_parent_ops = &gicp_msi_parent_ops;
 242         return 0;
 243 }
 244
 245 static const struct of_device_id mvebu_gicp_of_match[] = {
 246         { .compatible = "marvell,ap806-gicp", },
 247         {},
 248 };
 249
 250 static struct platform_driver mvebu_gicp_driver = {
 251         .probe  = mvebu_gicp_probe,
 252         .driver = {
 253                 .name = "mvebu-gicp",
 254                 .of_match_table = mvebu_gicp_of_match,
 255         },
 256 };
 257 builtin_platform_driver(mvebu_gicp_driver);