drivers/irqchip/irq-mbigen.c

   1 /*
   2  * Copyright (C) 2015 Hisilicon Limited, All Rights Reserved.
   3  * Author: Jun Ma <majun258@huawei.com>
   4  * Author: Yun Wu <wuyun.wu@huawei.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include <linux/interrupt.h>
  20 #include <linux/irqchip.h>
  21 #include <linux/module.h>
  22 #include <linux/msi.h>
  23 #include <linux/of_address.h>
  24 #include <linux/of_irq.h>
  25 #include <linux/of_platform.h>
  26 #include <linux/platform_device.h>
  27 #include <linux/slab.h>
  28
  29 /* Interrupt numbers per mbigen node supported */
  30 #define IRQS_PER_MBIGEN_NODE            128
  31
  32 /* 64 irqs (Pin0-pin63) are reserved for each mbigen chip */
  33 #define RESERVED_IRQ_PER_MBIGEN_CHIP    64
  34
  35 /* The maximum IRQ pin number of mbigen chip(start from 0) */
  36 #define MAXIMUM_IRQ_PIN_NUM             1407
  37
  38 /**
  39  * In mbigen vector register
  40  * bit[21:12]:  event id value
  41  * bit[11:0]:   device id
  42  */
  43 #define IRQ_EVENT_ID_SHIFT              12
  44 #define IRQ_EVENT_ID_MASK               0x3ff
  45
  46 /* register range of each mbigen node */
  47 #define MBIGEN_NODE_OFFSET              0x1000
  48
  49 /* offset of vector register in mbigen node */
  50 #define REG_MBIGEN_VEC_OFFSET           0x200
  51
  52 /**
  53  * offset of clear register in mbigen node
  54  * This register is used to clear the status
  55  * of interrupt
  56  */
  57 #define REG_MBIGEN_CLEAR_OFFSET         0xa000
  58
  59 /**
  60  * offset of interrupt type register
  61  * This register is used to configure interrupt
  62  * trigger type
  63  */
  64 #define REG_MBIGEN_TYPE_OFFSET          0x0
  65
  66 /**
  67  * struct mbigen_device - holds the information of mbigen device.
  68  *
  69  * @pdev:               pointer to the platform device structure of mbigen chip.
  70  * @base:               mapped address of this mbigen chip.
  71  */
  72 struct mbigen_device {
  73         struct platform_device  *pdev;
  74         void __iomem            *base;
  75 };
  76
  77 static inline unsigned int get_mbigen_vec_reg(irq_hw_number_t hwirq)
  78 {
  79         unsigned int nid, pin;
  80
  81         hwirq -= RESERVED_IRQ_PER_MBIGEN_CHIP;
  82         nid = hwirq / IRQS_PER_MBIGEN_NODE + 1;
  83         pin = hwirq % IRQS_PER_MBIGEN_NODE;
  84
  85         return pin * 4 + nid * MBIGEN_NODE_OFFSET
  86                         + REG_MBIGEN_VEC_OFFSET;
  87 }
  88
  89 static inline void get_mbigen_type_reg(irq_hw_number_t hwirq,
  90                                         u32 *mask, u32 *addr)
  91 {
  92         unsigned int nid, irq_ofst, ofst;
  93
  94         hwirq -= RESERVED_IRQ_PER_MBIGEN_CHIP;
  95         nid = hwirq / IRQS_PER_MBIGEN_NODE + 1;
  96         irq_ofst = hwirq % IRQS_PER_MBIGEN_NODE;
  97
  98         *mask = 1 << (irq_ofst % 32);
  99         ofst = irq_ofst / 32 * 4;
 100
 101         *addr = ofst + nid * MBIGEN_NODE_OFFSET
 102                 + REG_MBIGEN_TYPE_OFFSET;
 103 }
 104
 105 static inline void get_mbigen_clear_reg(irq_hw_number_t hwirq,
 106                                         u32 *mask, u32 *addr)
 107 {
 108         unsigned int ofst;
 109
 110         hwirq -= RESERVED_IRQ_PER_MBIGEN_CHIP;
 111         ofst = hwirq / 32 * 4;
 112
 113         *mask = 1 << (hwirq % 32);
 114         *addr = ofst + REG_MBIGEN_CLEAR_OFFSET;
 115 }
 116
 117 static void mbigen_eoi_irq(struct irq_data *data)
 118 {
 119         void __iomem *base = data->chip_data;
 120         u32 mask, addr;
 121
 122         get_mbigen_clear_reg(data->hwirq, &mask, &addr);
 123
 124         writel_relaxed(mask, base + addr);
 125
 126         irq_chip_eoi_parent(data);
 127 }
 128
 129 static int mbigen_set_type(struct irq_data *data, unsigned int type)
 130 {
 131         void __iomem *base = data->chip_data;
 132         u32 mask, addr, val;
 133
 134         if (type != IRQ_TYPE_LEVEL_HIGH && type != IRQ_TYPE_EDGE_RISING)
 135                 return -EINVAL;
 136
 137         get_mbigen_type_reg(data->hwirq, &mask, &addr);
 138
 139         val = readl_relaxed(base + addr);
 140
 141         if (type == IRQ_TYPE_LEVEL_HIGH)
 142                 val |= mask;
 143         else
 144                 val &= ~mask;
 145
 146         writel_relaxed(val, base + addr);
 147
 148         return 0;
 149 }
 150
 151 static struct irq_chip mbigen_irq_chip = {
 152         .name =                 "mbigen-v2",
 153         .irq_mask =             irq_chip_mask_parent,
 154         .irq_unmask =           irq_chip_unmask_parent,
 155         .irq_eoi =              mbigen_eoi_irq,
 156         .irq_set_type =         mbigen_set_type,
 157         .irq_set_affinity =     irq_chip_set_affinity_parent,
 158 };
 159
 160 static void mbigen_write_msg(struct msi_desc *desc, struct msi_msg *msg)
 161 {
 162         struct irq_data *d = irq_get_irq_data(desc->irq);
 163         void __iomem *base = d->chip_data;
 164         u32 val;
 165
 166         base += get_mbigen_vec_reg(d->hwirq);
 167         val = readl_relaxed(base);
 168
 169         val &= ~(IRQ_EVENT_ID_MASK << IRQ_EVENT_ID_SHIFT);
 170         val |= (msg->data << IRQ_EVENT_ID_SHIFT);
 171
 172         /* The address of doorbell is encoded in mbigen register by default
 173          * So,we don't need to program the doorbell address at here
 174          */
 175         writel_relaxed(val, base);
 176 }
 177
 178 static int mbigen_domain_translate(struct irq_domain *d,
 179                                     struct irq_fwspec *fwspec,
 180                                     unsigned long *hwirq,
 181                                     unsigned int *type)
 182 {
 183         if (is_of_node(fwspec->fwnode)) {
 184                 if (fwspec->param_count != 2)
 185                         return -EINVAL;
 186
 187                 if ((fwspec->param[0] > MAXIMUM_IRQ_PIN_NUM) ||
 188                         (fwspec->param[0] < RESERVED_IRQ_PER_MBIGEN_CHIP))
 189                         return -EINVAL;
 190                 else
 191                         *hwirq = fwspec->param[0];
 192
 193                 /* If there is no valid irq type, just use the default type */
 194                 if ((fwspec->param[1] == IRQ_TYPE_EDGE_RISING) ||
 195                         (fwspec->param[1] == IRQ_TYPE_LEVEL_HIGH))
 196                         *type = fwspec->param[1];
 197                 else
 198                         return -EINVAL;
 199
 200                 return 0;
 201         }
 202         return -EINVAL;
 203 }
 204
 205 static int mbigen_irq_domain_alloc(struct irq_domain *domain,
 206                                         unsigned int virq,
 207                                         unsigned int nr_irqs,
 208                                         void *args)
 209 {
 210         struct irq_fwspec *fwspec = args;
 211         irq_hw_number_t hwirq;
 212         unsigned int type;
 213         struct mbigen_device *mgn_chip;
 214         int i, err;
 215
 216         err = mbigen_domain_translate(domain, fwspec, &hwirq, &type);
 217         if (err)
 218                 return err;
 219
 220         err = platform_msi_domain_alloc(domain, virq, nr_irqs);
 221         if (err)
 222                 return err;
 223
 224         mgn_chip = platform_msi_get_host_data(domain);
 225
 226         for (i = 0; i < nr_irqs; i++)
 227                 irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
 228                                       &mbigen_irq_chip, mgn_chip->base);
 229
 230         return 0;
 231 }
 232
 233 static struct irq_domain_ops mbigen_domain_ops = {
 234         .translate      = mbigen_domain_translate,
 235         .alloc          = mbigen_irq_domain_alloc,
 236         .free           = irq_domain_free_irqs_common,
 237 };
 238
 239 static int mbigen_device_probe(struct platform_device *pdev)
 240 {
 241         struct mbigen_device *mgn_chip;
 242         struct platform_device *child;
 243         struct irq_domain *domain;
 244         struct device_node *np;
 245         struct device *parent;
 246         struct resource *res;
 247         u32 num_pins;
 248
 249         mgn_chip = devm_kzalloc(&pdev->dev, sizeof(*mgn_chip), GFP_KERNEL);
 250         if (!mgn_chip)
 251                 return -ENOMEM;
 252
 253         mgn_chip->pdev = pdev;
 254
 255         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 256         mgn_chip->base = devm_ioremap_resource(&pdev->dev, res);
 257         if (IS_ERR(mgn_chip->base))
 258                 return PTR_ERR(mgn_chip->base);
 259
 260         for_each_child_of_node(pdev->dev.of_node, np) {
 261                 if (!of_property_read_bool(np, "interrupt-controller"))
 262                         continue;
 263
 264                 parent = platform_bus_type.dev_root;
 265                 child = of_platform_device_create(np, NULL, parent);
 266                 if (!child)
 267                         return -ENOMEM;
 268
 269                 if (of_property_read_u32(child->dev.of_node, "num-pins",
 270                                          &num_pins) < 0) {
 271                         dev_err(&pdev->dev, "No num-pins property\n");
 272                         return -EINVAL;
 273                 }
 274
 275                 domain = platform_msi_create_device_domain(&child->dev, num_pins,
 276                                                            mbigen_write_msg,
 277                                                            &mbigen_domain_ops,
 278                                                            mgn_chip);
 279                 if (!domain)
 280                         return -ENOMEM;
 281         }
 282
 283         platform_set_drvdata(pdev, mgn_chip);
 284         return 0;
 285 }
 286
 287 static const struct of_device_id mbigen_of_match[] = {
 288         { .compatible = "hisilicon,mbigen-v2" },
 289         { /* END */ }
 290 };
 291 MODULE_DEVICE_TABLE(of, mbigen_of_match);
 292
 293 static struct platform_driver mbigen_platform_driver = {
 294         .driver = {
 295                 .name           = "Hisilicon MBIGEN-V2",
 296                 .owner          = THIS_MODULE,
 297                 .of_match_table = mbigen_of_match,
 298         },
 299         .probe                  = mbigen_device_probe,
 300 };
 301
 302 module_platform_driver(mbigen_platform_driver);
 303
 304 MODULE_AUTHOR("Jun Ma <majun258@huawei.com>");
 305 MODULE_AUTHOR("Yun Wu <wuyun.wu@huawei.com>");
 306 MODULE_LICENSE("GPL");
 307 MODULE_DESCRIPTION("Hisilicon MBI Generator driver");