drivers/irqchip/irq-partition-percpu.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2016 ARM Limited, All Rights Reserved.
   4  * Author: Marc Zyngier <marc.zyngier@arm.com>
   5  */
   6
   7 #include <linux/bitops.h>
   8 #include <linux/interrupt.h>
   9 #include <linux/irqchip.h>
  10 #include <linux/irqchip/chained_irq.h>
  11 #include <linux/irqchip/irq-partition-percpu.h>
  12 #include <linux/irqdomain.h>
  13 #include <linux/seq_file.h>
  14 #include <linux/slab.h>
  15
  16 struct partition_desc {
  17         int                             nr_parts;
  18         struct partition_affinity       *parts;
  19         struct irq_domain               *domain;
  20         struct irq_desc                 *chained_desc;
  21         unsigned long                   *bitmap;
  22         struct irq_domain_ops           ops;
  23 };
  24
  25 static bool partition_check_cpu(struct partition_desc *part,
  26                                 unsigned int cpu, unsigned int hwirq)
  27 {
  28         return cpumask_test_cpu(cpu, &part->parts[hwirq].mask);
  29 }
  30
  31 static void partition_irq_mask(struct irq_data *d)
  32 {
  33         struct partition_desc *part = irq_data_get_irq_chip_data(d);
  34         struct irq_chip *chip = irq_desc_get_chip(part->chained_desc);
  35         struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
  36
  37         if (partition_check_cpu(part, smp_processor_id(), d->hwirq) &&
  38             chip->irq_mask)
  39                 chip->irq_mask(data);
  40 }
  41
  42 static void partition_irq_unmask(struct irq_data *d)
  43 {
  44         struct partition_desc *part = irq_data_get_irq_chip_data(d);
  45         struct irq_chip *chip = irq_desc_get_chip(part->chained_desc);
  46         struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
  47
  48         if (partition_check_cpu(part, smp_processor_id(), d->hwirq) &&
  49             chip->irq_unmask)
  50                 chip->irq_unmask(data);
  51 }
  52
  53 static int partition_irq_set_irqchip_state(struct irq_data *d,
  54                                            enum irqchip_irq_state which,
  55                                            bool val)
  56 {
  57         struct partition_desc *part = irq_data_get_irq_chip_data(d);
  58         struct irq_chip *chip = irq_desc_get_chip(part->chained_desc);
  59         struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
  60
  61         if (partition_check_cpu(part, smp_processor_id(), d->hwirq) &&
  62             chip->irq_set_irqchip_state)
  63                 return chip->irq_set_irqchip_state(data, which, val);
  64
  65         return -EINVAL;
  66 }
  67
  68 static int partition_irq_get_irqchip_state(struct irq_data *d,
  69                                            enum irqchip_irq_state which,
  70                                            bool *val)
  71 {
  72         struct partition_desc *part = irq_data_get_irq_chip_data(d);
  73         struct irq_chip *chip = irq_desc_get_chip(part->chained_desc);
  74         struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
  75
  76         if (partition_check_cpu(part, smp_processor_id(), d->hwirq) &&
  77             chip->irq_get_irqchip_state)
  78                 return chip->irq_get_irqchip_state(data, which, val);
  79
  80         return -EINVAL;
  81 }
  82
  83 static int partition_irq_set_type(struct irq_data *d, unsigned int type)
  84 {
  85         struct partition_desc *part = irq_data_get_irq_chip_data(d);
  86         struct irq_chip *chip = irq_desc_get_chip(part->chained_desc);
  87         struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
  88
  89         if (chip->irq_set_type)
  90                 return chip->irq_set_type(data, type);
  91
  92         return -EINVAL;
  93 }
  94
  95 static void partition_irq_print_chip(struct irq_data *d, struct seq_file *p)
  96 {
  97         struct partition_desc *part = irq_data_get_irq_chip_data(d);
  98         struct irq_chip *chip = irq_desc_get_chip(part->chained_desc);
  99         struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
 100
 101         seq_printf(p, " %5s-%lu", chip->name, data->hwirq);
 102 }
 103
 104 static struct irq_chip partition_irq_chip = {
 105         .irq_mask               = partition_irq_mask,
 106         .irq_unmask             = partition_irq_unmask,
 107         .irq_set_type           = partition_irq_set_type,
 108         .irq_get_irqchip_state  = partition_irq_get_irqchip_state,
 109         .irq_set_irqchip_state  = partition_irq_set_irqchip_state,
 110         .irq_print_chip         = partition_irq_print_chip,
 111 };
 112
 113 static void partition_handle_irq(struct irq_desc *desc)
 114 {
 115         struct partition_desc *part = irq_desc_get_handler_data(desc);
 116         struct irq_chip *chip = irq_desc_get_chip(desc);
 117         int cpu = smp_processor_id();
 118         int hwirq;
 119
 120         chained_irq_enter(chip, desc);
 121
 122         for_each_set_bit(hwirq, part->bitmap, part->nr_parts) {
 123                 if (partition_check_cpu(part, cpu, hwirq))
 124                         break;
 125         }
 126
 127         if (unlikely(hwirq == part->nr_parts))
 128                 handle_bad_irq(desc);
 129         else
 130                 generic_handle_domain_irq(part->domain, hwirq);
 131
 132         chained_irq_exit(chip, desc);
 133 }
 134
 135 static int partition_domain_alloc(struct irq_domain *domain, unsigned int virq,
 136                                   unsigned int nr_irqs, void *arg)
 137 {
 138         int ret;
 139         irq_hw_number_t hwirq;
 140         unsigned int type;
 141         struct irq_fwspec *fwspec = arg;
 142         struct partition_desc *part;
 143
 144         BUG_ON(nr_irqs != 1);
 145         ret = domain->ops->translate(domain, fwspec, &hwirq, &type);
 146         if (ret)
 147                 return ret;
 148
 149         part = domain->host_data;
 150
 151         set_bit(hwirq, part->bitmap);
 152         irq_set_chained_handler_and_data(irq_desc_get_irq(part->chained_desc),
 153                                          partition_handle_irq, part);
 154         irq_set_percpu_devid_partition(virq, &part->parts[hwirq].mask);
 155         irq_domain_set_info(domain, virq, hwirq, &partition_irq_chip, part,
 156                             handle_percpu_devid_irq, NULL, NULL);
 157         irq_set_status_flags(virq, IRQ_NOAUTOEN);
 158
 159         return 0;
 160 }
 161
 162 static void partition_domain_free(struct irq_domain *domain, unsigned int virq,
 163                                   unsigned int nr_irqs)
 164 {
 165         struct irq_data *d;
 166
 167         BUG_ON(nr_irqs != 1);
 168
 169         d = irq_domain_get_irq_data(domain, virq);
 170         irq_set_handler(virq, NULL);
 171         irq_domain_reset_irq_data(d);
 172 }
 173
 174 int partition_translate_id(struct partition_desc *desc, void *partition_id)
 175 {
 176         struct partition_affinity *part = NULL;
 177         int i;
 178
 179         for (i = 0; i < desc->nr_parts; i++) {
 180                 if (desc->parts[i].partition_id == partition_id) {
 181                         part = &desc->parts[i];
 182                         break;
 183                 }
 184         }
 185
 186         if (WARN_ON(!part)) {
 187                 pr_err("Failed to find partition\n");
 188                 return -EINVAL;
 189         }
 190
 191         return i;
 192 }
 193
 194 struct partition_desc *partition_create_desc(struct fwnode_handle *fwnode,
 195                                              struct partition_affinity *parts,
 196                                              int nr_parts,
 197                                              int chained_irq,
 198                                              const struct irq_domain_ops *ops)
 199 {
 200         struct partition_desc *desc;
 201         struct irq_domain *d;
 202
 203         BUG_ON(!ops->select || !ops->translate);
 204
 205         desc = kzalloc(sizeof(*desc), GFP_KERNEL);
 206         if (!desc)
 207                 return NULL;
 208
 209         desc->ops = *ops;
 210         desc->ops.free = partition_domain_free;
 211         desc->ops.alloc = partition_domain_alloc;
 212
 213         d = irq_domain_create_linear(fwnode, nr_parts, &desc->ops, desc);
 214         if (!d)
 215                 goto out;
 216         desc->domain = d;
 217
 218         desc->bitmap = bitmap_zalloc(nr_parts, GFP_KERNEL);
 219         if (WARN_ON(!desc->bitmap))
 220                 goto out;
 221
 222         desc->chained_desc = irq_to_desc(chained_irq);
 223         desc->nr_parts = nr_parts;
 224         desc->parts = parts;
 225
 226         return desc;
 227 out:
 228         if (d)
 229                 irq_domain_remove(d);
 230         kfree(desc);
 231
 232         return NULL;
 233 }
 234
 235 struct irq_domain *partition_get_domain(struct partition_desc *dsc)
 236 {
 237         if (dsc)
 238                 return dsc->domain;
 239
 240         return NULL;
 241 }