drivers/irqchip/irq-ls-extirq.c

   1 // SPDX-License-Identifier: GPL-2.0
   2
   3 #define pr_fmt(fmt) "irq-ls-extirq: " fmt
   4
   5 #include <linux/irq.h>
   6 #include <linux/irqchip.h>
   7 #include <linux/irqdomain.h>
   8 #include <linux/of.h>
   9 #include <linux/of_address.h>
  10 #include <linux/slab.h>
  11
  12 #include <dt-bindings/interrupt-controller/arm-gic.h>
  13
  14 #define MAXIRQ 12
  15 #define LS1021A_SCFGREVCR 0x200
  16
  17 struct ls_extirq_data {
  18         void __iomem            *intpcr;
  19         raw_spinlock_t          lock;
  20         bool                    big_endian;
  21         bool                    is_ls1021a_or_ls1043a;
  22         u32                     nirq;
  23         struct irq_fwspec       map[MAXIRQ];
  24 };
  25
  26 static void ls_extirq_intpcr_rmw(struct ls_extirq_data *priv, u32 mask,
  27                                  u32 value)
  28 {
  29         u32 intpcr;
  30
  31         /*
  32          * Serialize concurrent calls to ls_extirq_set_type() from multiple
  33          * IRQ descriptors, making sure the read-modify-write is atomic.
  34          */
  35         raw_spin_lock(&priv->lock);
  36
  37         if (priv->big_endian)
  38                 intpcr = ioread32be(priv->intpcr);
  39         else
  40                 intpcr = ioread32(priv->intpcr);
  41
  42         intpcr &= ~mask;
  43         intpcr |= value;
  44
  45         if (priv->big_endian)
  46                 iowrite32be(intpcr, priv->intpcr);
  47         else
  48                 iowrite32(intpcr, priv->intpcr);
  49
  50         raw_spin_unlock(&priv->lock);
  51 }
  52
  53 static int
  54 ls_extirq_set_type(struct irq_data *data, unsigned int type)
  55 {
  56         struct ls_extirq_data *priv = data->chip_data;
  57         irq_hw_number_t hwirq = data->hwirq;
  58         u32 value, mask;
  59
  60         if (priv->is_ls1021a_or_ls1043a)
  61                 mask = 1U << (31 - hwirq);
  62         else
  63                 mask = 1U << hwirq;
  64
  65         switch (type) {
  66         case IRQ_TYPE_LEVEL_LOW:
  67                 type = IRQ_TYPE_LEVEL_HIGH;
  68                 value = mask;
  69                 break;
  70         case IRQ_TYPE_EDGE_FALLING:
  71                 type = IRQ_TYPE_EDGE_RISING;
  72                 value = mask;
  73                 break;
  74         case IRQ_TYPE_LEVEL_HIGH:
  75         case IRQ_TYPE_EDGE_RISING:
  76                 value = 0;
  77                 break;
  78         default:
  79                 return -EINVAL;
  80         }
  81
  82         ls_extirq_intpcr_rmw(priv, mask, value);
  83
  84         return irq_chip_set_type_parent(data, type);
  85 }
  86
  87 static struct irq_chip ls_extirq_chip = {
  88         .name                   = "ls-extirq",
  89         .irq_mask               = irq_chip_mask_parent,
  90         .irq_unmask             = irq_chip_unmask_parent,
  91         .irq_eoi                = irq_chip_eoi_parent,
  92         .irq_set_type           = ls_extirq_set_type,
  93         .irq_retrigger          = irq_chip_retrigger_hierarchy,
  94         .irq_set_affinity       = irq_chip_set_affinity_parent,
  95         .flags                  = IRQCHIP_SET_TYPE_MASKED | IRQCHIP_SKIP_SET_WAKE,
  96 };
  97
  98 static int
  99 ls_extirq_domain_alloc(struct irq_domain *domain, unsigned int virq,
 100                        unsigned int nr_irqs, void *arg)
 101 {
 102         struct ls_extirq_data *priv = domain->host_data;
 103         struct irq_fwspec *fwspec = arg;
 104         irq_hw_number_t hwirq;
 105
 106         if (fwspec->param_count != 2)
 107                 return -EINVAL;
 108
 109         hwirq = fwspec->param[0];
 110         if (hwirq >= priv->nirq)
 111                 return -EINVAL;
 112
 113         irq_domain_set_hwirq_and_chip(domain, virq, hwirq, &ls_extirq_chip,
 114                                       priv);
 115
 116         return irq_domain_alloc_irqs_parent(domain, virq, 1, &priv->map[hwirq]);
 117 }
 118
 119 static const struct irq_domain_ops extirq_domain_ops = {
 120         .xlate          = irq_domain_xlate_twocell,
 121         .alloc          = ls_extirq_domain_alloc,
 122         .free           = irq_domain_free_irqs_common,
 123 };
 124
 125 static int
 126 ls_extirq_parse_map(struct ls_extirq_data *priv, struct device_node *node)
 127 {
 128         const __be32 *map;
 129         u32 mapsize;
 130         int ret;
 131
 132         map = of_get_property(node, "interrupt-map", &mapsize);
 133         if (!map)
 134                 return -ENOENT;
 135         if (mapsize % sizeof(*map))
 136                 return -EINVAL;
 137         mapsize /= sizeof(*map);
 138
 139         while (mapsize) {
 140                 struct device_node *ipar;
 141                 u32 hwirq, intsize, j;
 142
 143                 if (mapsize < 3)
 144                         return -EINVAL;
 145                 hwirq = be32_to_cpup(map);
 146                 if (hwirq >= MAXIRQ)
 147                         return -EINVAL;
 148                 priv->nirq = max(priv->nirq, hwirq + 1);
 149
 150                 ipar = of_find_node_by_phandle(be32_to_cpup(map + 2));
 151                 map += 3;
 152                 mapsize -= 3;
 153                 if (!ipar)
 154                         return -EINVAL;
 155                 priv->map[hwirq].fwnode = &ipar->fwnode;
 156                 ret = of_property_read_u32(ipar, "#interrupt-cells", &intsize);
 157                 if (ret)
 158                         return ret;
 159
 160                 if (intsize > mapsize)
 161                         return -EINVAL;
 162
 163                 priv->map[hwirq].param_count = intsize;
 164                 for (j = 0; j < intsize; ++j)
 165                         priv->map[hwirq].param[j] = be32_to_cpup(map++);
 166                 mapsize -= intsize;
 167         }
 168         return 0;
 169 }
 170
 171 static int __init
 172 ls_extirq_of_init(struct device_node *node, struct device_node *parent)
 173 {
 174         struct irq_domain *domain, *parent_domain;
 175         struct ls_extirq_data *priv;
 176         int ret;
 177
 178         parent_domain = irq_find_host(parent);
 179         if (!parent_domain) {
 180                 pr_err("Cannot find parent domain\n");
 181                 ret = -ENODEV;
 182                 goto err_irq_find_host;
 183         }
 184
 185         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 186         if (!priv) {
 187                 ret = -ENOMEM;
 188                 goto err_alloc_priv;
 189         }
 190
 191         /*
 192          * All extirq OF nodes are under a scfg/syscon node with
 193          * the 'ranges' property
 194          */
 195         priv->intpcr = of_iomap(node, 0);
 196         if (!priv->intpcr) {
 197                 pr_err("Cannot ioremap OF node %pOF\n", node);
 198                 ret = -ENOMEM;
 199                 goto err_iomap;
 200         }
 201
 202         ret = ls_extirq_parse_map(priv, node);
 203         if (ret)
 204                 goto err_parse_map;
 205
 206         priv->big_endian = of_device_is_big_endian(node->parent);
 207         priv->is_ls1021a_or_ls1043a = of_device_is_compatible(node, "fsl,ls1021a-extirq") ||
 208                                       of_device_is_compatible(node, "fsl,ls1043a-extirq");
 209         raw_spin_lock_init(&priv->lock);
 210
 211         domain = irq_domain_add_hierarchy(parent_domain, 0, priv->nirq, node,
 212                                           &extirq_domain_ops, priv);
 213         if (!domain) {
 214                 ret = -ENOMEM;
 215                 goto err_add_hierarchy;
 216         }
 217
 218         return 0;
 219
 220 err_add_hierarchy:
 221 err_parse_map:
 222         iounmap(priv->intpcr);
 223 err_iomap:
 224         kfree(priv);
 225 err_alloc_priv:
 226 err_irq_find_host:
 227         return ret;
 228 }
 229
 230 IRQCHIP_DECLARE(ls1021a_extirq, "fsl,ls1021a-extirq", ls_extirq_of_init);
 231 IRQCHIP_DECLARE(ls1043a_extirq, "fsl,ls1043a-extirq", ls_extirq_of_init);
 232 IRQCHIP_DECLARE(ls1088a_extirq, "fsl,ls1088a-extirq", ls_extirq_of_init);