drivers/irqchip/irq-mvebu-icu.c

   1 /*
   2  * Copyright (C) 2017 Marvell
   3  *
   4  * Hanna Hawa <hannah@marvell.com>
   5  * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
   6  *
   7  * This file is licensed under the terms of the GNU General Public
   8  * License version 2. This program is licensed "as is" without any
   9  * warranty of any kind, whether express or implied.
  10  */
  11
  12 #include <linux/interrupt.h>
  13 #include <linux/irq.h>
  14 #include <linux/irqchip.h>
  15 #include <linux/irqdomain.h>
  16 #include <linux/jump_label.h>
  17 #include <linux/kernel.h>
  18 #include <linux/msi.h>
  19 #include <linux/of_irq.h>
  20 #include <linux/of_platform.h>
  21 #include <linux/platform_device.h>
  22
  23 #include <dt-bindings/interrupt-controller/mvebu-icu.h>
  24
  25 /* ICU registers */
  26 #define ICU_SETSPI_NSR_AL       0x10
  27 #define ICU_SETSPI_NSR_AH       0x14
  28 #define ICU_CLRSPI_NSR_AL       0x18
  29 #define ICU_CLRSPI_NSR_AH       0x1c
  30 #define ICU_SET_SEI_AL          0x50
  31 #define ICU_SET_SEI_AH          0x54
  32 #define ICU_CLR_SEI_AL          0x58
  33 #define ICU_CLR_SEI_AH          0x5C
  34 #define ICU_INT_CFG(x)          (0x100 + 4 * (x))
  35 #define   ICU_INT_ENABLE        BIT(24)
  36 #define   ICU_IS_EDGE           BIT(28)
  37 #define   ICU_GROUP_SHIFT       29
  38
  39 /* ICU definitions */
  40 #define ICU_MAX_IRQS            207
  41 #define ICU_SATA0_ICU_ID        109
  42 #define ICU_SATA1_ICU_ID        107
  43
  44 struct mvebu_icu_subset_data {
  45         unsigned int icu_group;
  46         unsigned int offset_set_ah;
  47         unsigned int offset_set_al;
  48         unsigned int offset_clr_ah;
  49         unsigned int offset_clr_al;
  50 };
  51
  52 struct mvebu_icu {
  53         void __iomem *base;
  54         struct device *dev;
  55 };
  56
  57 struct mvebu_icu_msi_data {
  58         struct mvebu_icu *icu;
  59         atomic_t initialized;
  60         const struct mvebu_icu_subset_data *subset_data;
  61 };
  62
  63 struct mvebu_icu_irq_data {
  64         struct mvebu_icu *icu;
  65         unsigned int icu_group;
  66         unsigned int type;
  67 };
  68
  69 static DEFINE_STATIC_KEY_FALSE(legacy_bindings);
  70
  71 static void mvebu_icu_init(struct mvebu_icu *icu,
  72                            struct mvebu_icu_msi_data *msi_data,
  73                            struct msi_msg *msg)
  74 {
  75         const struct mvebu_icu_subset_data *subset = msi_data->subset_data;
  76
  77         if (atomic_cmpxchg(&msi_data->initialized, false, true))
  78                 return;
  79
  80         /* Set 'SET' ICU SPI message address in AP */
  81         writel_relaxed(msg[0].address_hi, icu->base + subset->offset_set_ah);
  82         writel_relaxed(msg[0].address_lo, icu->base + subset->offset_set_al);
  83
  84         if (subset->icu_group != ICU_GRP_NSR)
  85                 return;
  86
  87         /* Set 'CLEAR' ICU SPI message address in AP (level-MSI only) */
  88         writel_relaxed(msg[1].address_hi, icu->base + subset->offset_clr_ah);
  89         writel_relaxed(msg[1].address_lo, icu->base + subset->offset_clr_al);
  90 }
  91
  92 static void mvebu_icu_write_msg(struct msi_desc *desc, struct msi_msg *msg)
  93 {
  94         struct irq_data *d = irq_get_irq_data(desc->irq);
  95         struct mvebu_icu_msi_data *msi_data = platform_msi_get_host_data(d->domain);
  96         struct mvebu_icu_irq_data *icu_irqd = d->chip_data;
  97         struct mvebu_icu *icu = icu_irqd->icu;
  98         unsigned int icu_int;
  99
 100         if (msg->address_lo || msg->address_hi) {
 101                 /* One off initialization per domain */
 102                 mvebu_icu_init(icu, msi_data, msg);
 103                 /* Configure the ICU with irq number & type */
 104                 icu_int = msg->data | ICU_INT_ENABLE;
 105                 if (icu_irqd->type & IRQ_TYPE_EDGE_RISING)
 106                         icu_int |= ICU_IS_EDGE;
 107                 icu_int |= icu_irqd->icu_group << ICU_GROUP_SHIFT;
 108         } else {
 109                 /* De-configure the ICU */
 110                 icu_int = 0;
 111         }
 112
 113         writel_relaxed(icu_int, icu->base + ICU_INT_CFG(d->hwirq));
 114
 115         /*
 116          * The SATA unit has 2 ports, and a dedicated ICU entry per
 117          * port. The ahci sata driver supports only one irq interrupt
 118          * per SATA unit. To solve this conflict, we configure the 2
 119          * SATA wired interrupts in the south bridge into 1 GIC
 120          * interrupt in the north bridge. Even if only a single port
 121          * is enabled, if sata node is enabled, both interrupts are
 122          * configured (regardless of which port is actually in use).
 123          */
 124         if (d->hwirq == ICU_SATA0_ICU_ID || d->hwirq == ICU_SATA1_ICU_ID) {
 125                 writel_relaxed(icu_int,
 126                                icu->base + ICU_INT_CFG(ICU_SATA0_ICU_ID));
 127                 writel_relaxed(icu_int,
 128                                icu->base + ICU_INT_CFG(ICU_SATA1_ICU_ID));
 129         }
 130 }
 131
 132 static struct irq_chip mvebu_icu_nsr_chip = {
 133         .name                   = "ICU-NSR",
 134         .irq_mask               = irq_chip_mask_parent,
 135         .irq_unmask             = irq_chip_unmask_parent,
 136         .irq_eoi                = irq_chip_eoi_parent,
 137         .irq_set_type           = irq_chip_set_type_parent,
 138         .irq_set_affinity       = irq_chip_set_affinity_parent,
 139 };
 140
 141 static struct irq_chip mvebu_icu_sei_chip = {
 142         .name                   = "ICU-SEI",
 143         .irq_ack                = irq_chip_ack_parent,
 144         .irq_mask               = irq_chip_mask_parent,
 145         .irq_unmask             = irq_chip_unmask_parent,
 146         .irq_set_type           = irq_chip_set_type_parent,
 147         .irq_set_affinity       = irq_chip_set_affinity_parent,
 148 };
 149
 150 static int
 151 mvebu_icu_irq_domain_translate(struct irq_domain *d, struct irq_fwspec *fwspec,
 152                                unsigned long *hwirq, unsigned int *type)
 153 {
 154         struct mvebu_icu_msi_data *msi_data = platform_msi_get_host_data(d);
 155         struct mvebu_icu *icu = platform_msi_get_host_data(d);
 156         unsigned int param_count = static_branch_unlikely(&legacy_bindings) ? 3 : 2;
 157
 158         /* Check the count of the parameters in dt */
 159         if (WARN_ON(fwspec->param_count != param_count)) {
 160                 dev_err(icu->dev, "wrong ICU parameter count %d\n",
 161                         fwspec->param_count);
 162                 return -EINVAL;
 163         }
 164
 165         if (static_branch_unlikely(&legacy_bindings)) {
 166                 *hwirq = fwspec->param[1];
 167                 *type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK;
 168                 if (fwspec->param[0] != ICU_GRP_NSR) {
 169                         dev_err(icu->dev, "wrong ICU group type %x\n",
 170                                 fwspec->param[0]);
 171                         return -EINVAL;
 172                 }
 173         } else {
 174                 *hwirq = fwspec->param[0];
 175                 *type = fwspec->param[1] & IRQ_TYPE_SENSE_MASK;
 176
 177                 /*
 178                  * The ICU receives level interrupts. While the NSR are also
 179                  * level interrupts, SEI are edge interrupts. Force the type
 180                  * here in this case. Please note that this makes the interrupt
 181                  * handling unreliable.
 182                  */
 183                 if (msi_data->subset_data->icu_group == ICU_GRP_SEI)
 184                         *type = IRQ_TYPE_EDGE_RISING;
 185         }
 186
 187         if (*hwirq >= ICU_MAX_IRQS) {
 188                 dev_err(icu->dev, "invalid interrupt number %ld\n", *hwirq);
 189                 return -EINVAL;
 190         }
 191
 192         return 0;
 193 }
 194
 195 static int
 196 mvebu_icu_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
 197                            unsigned int nr_irqs, void *args)
 198 {
 199         int err;
 200         unsigned long hwirq;
 201         struct irq_fwspec *fwspec = args;
 202         struct mvebu_icu_msi_data *msi_data = platform_msi_get_host_data(domain);
 203         struct mvebu_icu *icu = msi_data->icu;
 204         struct mvebu_icu_irq_data *icu_irqd;
 205         struct irq_chip *chip = &mvebu_icu_nsr_chip;
 206
 207         icu_irqd = kmalloc(sizeof(*icu_irqd), GFP_KERNEL);
 208         if (!icu_irqd)
 209                 return -ENOMEM;
 210
 211         err = mvebu_icu_irq_domain_translate(domain, fwspec, &hwirq,
 212                                              &icu_irqd->type);
 213         if (err) {
 214                 dev_err(icu->dev, "failed to translate ICU parameters\n");
 215                 goto free_irqd;
 216         }
 217
 218         if (static_branch_unlikely(&legacy_bindings))
 219                 icu_irqd->icu_group = fwspec->param[0];
 220         else
 221                 icu_irqd->icu_group = msi_data->subset_data->icu_group;
 222         icu_irqd->icu = icu;
 223
 224         err = platform_msi_domain_alloc(domain, virq, nr_irqs);
 225         if (err) {
 226                 dev_err(icu->dev, "failed to allocate ICU interrupt in parent domain\n");
 227                 goto free_irqd;
 228         }
 229
 230         /* Make sure there is no interrupt left pending by the firmware */
 231         err = irq_set_irqchip_state(virq, IRQCHIP_STATE_PENDING, false);
 232         if (err)
 233                 goto free_msi;
 234
 235         if (icu_irqd->icu_group == ICU_GRP_SEI)
 236                 chip = &mvebu_icu_sei_chip;
 237
 238         err = irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
 239                                             chip, icu_irqd);
 240         if (err) {
 241                 dev_err(icu->dev, "failed to set the data to IRQ domain\n");
 242                 goto free_msi;
 243         }
 244
 245         return 0;
 246
 247 free_msi:
 248         platform_msi_domain_free(domain, virq, nr_irqs);
 249 free_irqd:
 250         kfree(icu_irqd);
 251         return err;
 252 }
 253
 254 static void
 255 mvebu_icu_irq_domain_free(struct irq_domain *domain, unsigned int virq,
 256                           unsigned int nr_irqs)
 257 {
 258         struct irq_data *d = irq_get_irq_data(virq);
 259         struct mvebu_icu_irq_data *icu_irqd = d->chip_data;
 260
 261         kfree(icu_irqd);
 262
 263         platform_msi_domain_free(domain, virq, nr_irqs);
 264 }
 265
 266 static const struct irq_domain_ops mvebu_icu_domain_ops = {
 267         .translate = mvebu_icu_irq_domain_translate,
 268         .alloc     = mvebu_icu_irq_domain_alloc,
 269         .free      = mvebu_icu_irq_domain_free,
 270 };
 271
 272 static const struct mvebu_icu_subset_data mvebu_icu_nsr_subset_data = {
 273         .icu_group = ICU_GRP_NSR,
 274         .offset_set_ah = ICU_SETSPI_NSR_AH,
 275         .offset_set_al = ICU_SETSPI_NSR_AL,
 276         .offset_clr_ah = ICU_CLRSPI_NSR_AH,
 277         .offset_clr_al = ICU_CLRSPI_NSR_AL,
 278 };
 279
 280 static const struct mvebu_icu_subset_data mvebu_icu_sei_subset_data = {
 281         .icu_group = ICU_GRP_SEI,
 282         .offset_set_ah = ICU_SET_SEI_AH,
 283         .offset_set_al = ICU_SET_SEI_AL,
 284 };
 285
 286 static const struct of_device_id mvebu_icu_subset_of_match[] = {
 287         {
 288                 .compatible = "marvell,cp110-icu-nsr",
 289                 .data = &mvebu_icu_nsr_subset_data,
 290         },
 291         {
 292                 .compatible = "marvell,cp110-icu-sei",
 293                 .data = &mvebu_icu_sei_subset_data,
 294         },
 295         {},
 296 };
 297
 298 static int mvebu_icu_subset_probe(struct platform_device *pdev)
 299 {
 300         struct mvebu_icu_msi_data *msi_data;
 301         struct device_node *msi_parent_dn;
 302         struct device *dev = &pdev->dev;
 303         struct irq_domain *irq_domain;
 304
 305         msi_data = devm_kzalloc(dev, sizeof(*msi_data), GFP_KERNEL);
 306         if (!msi_data)
 307                 return -ENOMEM;
 308
 309         if (static_branch_unlikely(&legacy_bindings)) {
 310                 msi_data->icu = dev_get_drvdata(dev);
 311                 msi_data->subset_data = &mvebu_icu_nsr_subset_data;
 312         } else {
 313                 msi_data->icu = dev_get_drvdata(dev->parent);
 314                 msi_data->subset_data = of_device_get_match_data(dev);
 315         }
 316
 317         dev->msi_domain = of_msi_get_domain(dev, dev->of_node,
 318                                             DOMAIN_BUS_PLATFORM_MSI);
 319         if (!dev->msi_domain)
 320                 return -EPROBE_DEFER;
 321
 322         msi_parent_dn = irq_domain_get_of_node(dev->msi_domain);
 323         if (!msi_parent_dn)
 324                 return -ENODEV;
 325
 326         irq_domain = platform_msi_create_device_tree_domain(dev, ICU_MAX_IRQS,
 327                                                             mvebu_icu_write_msg,
 328                                                             &mvebu_icu_domain_ops,
 329                                                             msi_data);
 330         if (!irq_domain) {
 331                 dev_err(dev, "Failed to create ICU MSI domain\n");
 332                 return -ENOMEM;
 333         }
 334
 335         return 0;
 336 }
 337
 338 static struct platform_driver mvebu_icu_subset_driver = {
 339         .probe  = mvebu_icu_subset_probe,
 340         .driver = {
 341                 .name = "mvebu-icu-subset",
 342                 .of_match_table = mvebu_icu_subset_of_match,
 343         },
 344 };
 345 builtin_platform_driver(mvebu_icu_subset_driver);
 346
 347 static int mvebu_icu_probe(struct platform_device *pdev)
 348 {
 349         struct mvebu_icu *icu;
 350         struct resource *res;
 351         int i;
 352
 353         icu = devm_kzalloc(&pdev->dev, sizeof(struct mvebu_icu),
 354                            GFP_KERNEL);
 355         if (!icu)
 356                 return -ENOMEM;
 357
 358         icu->dev = &pdev->dev;
 359
 360         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 361         icu->base = devm_ioremap_resource(&pdev->dev, res);
 362         if (IS_ERR(icu->base)) {
 363                 dev_err(&pdev->dev, "Failed to map icu base address.\n");
 364                 return PTR_ERR(icu->base);
 365         }
 366
 367         /*
 368          * Legacy bindings: ICU is one node with one MSI parent: force manually
 369          *                  the probe of the NSR interrupts side.
 370          * New bindings: ICU node has children, one per interrupt controller
 371          *               having its own MSI parent: call platform_populate().
 372          * All ICU instances should use the same bindings.
 373          */
 374         if (!of_get_child_count(pdev->dev.of_node))
 375                 static_branch_enable(&legacy_bindings);
 376
 377         /*
 378          * Clean all ICU interrupts of type NSR and SEI, required to
 379          * avoid unpredictable SPI assignments done by firmware.
 380          */
 381         for (i = 0 ; i < ICU_MAX_IRQS ; i++) {
 382                 u32 icu_int, icu_grp;
 383
 384                 icu_int = readl_relaxed(icu->base + ICU_INT_CFG(i));
 385                 icu_grp = icu_int >> ICU_GROUP_SHIFT;
 386
 387                 if (icu_grp == ICU_GRP_NSR ||
 388                     (icu_grp == ICU_GRP_SEI &&
 389                      !static_branch_unlikely(&legacy_bindings)))
 390                         writel_relaxed(0x0, icu->base + ICU_INT_CFG(i));
 391         }
 392
 393         platform_set_drvdata(pdev, icu);
 394
 395         if (static_branch_unlikely(&legacy_bindings))
 396                 return mvebu_icu_subset_probe(pdev);
 397         else
 398                 return devm_of_platform_populate(&pdev->dev);
 399 }
 400
 401 static const struct of_device_id mvebu_icu_of_match[] = {
 402         { .compatible = "marvell,cp110-icu", },
 403         {},
 404 };
 405
 406 static struct platform_driver mvebu_icu_driver = {
 407         .probe  = mvebu_icu_probe,
 408         .driver = {
 409                 .name = "mvebu-icu",
 410                 .of_match_table = mvebu_icu_of_match,
 411         },
 412 };
 413 builtin_platform_driver(mvebu_icu_driver);