drivers/irqchip/irq-imx-mu-msi.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Freescale MU used as MSI controller
   4  *
   5  * Copyright (c) 2018 Pengutronix, Oleksij Rempel <o.rempel@pengutronix.de>
   6  * Copyright 2022 NXP
   7  *      Frank Li <Frank.Li@nxp.com>
   8  *      Peng Fan <peng.fan@nxp.com>
   9  *
  10  * Based on drivers/mailbox/imx-mailbox.c
  11  */
  12
  13 #include <linux/clk.h>
  14 #include <linux/irq.h>
  15 #include <linux/irqchip.h>
  16 #include <linux/irqchip/chained_irq.h>
  17 #include <linux/irqdomain.h>
  18 #include <linux/kernel.h>
  19 #include <linux/module.h>
  20 #include <linux/msi.h>
  21 #include <linux/of_irq.h>
  22 #include <linux/of_platform.h>
  23 #include <linux/pm_runtime.h>
  24 #include <linux/pm_domain.h>
  25 #include <linux/spinlock.h>
  26
  27 #include "irq-msi-lib.h"
  28
  29 #define IMX_MU_CHANS            4
  30
  31 enum imx_mu_xcr {
  32         IMX_MU_GIER,
  33         IMX_MU_GCR,
  34         IMX_MU_TCR,
  35         IMX_MU_RCR,
  36         IMX_MU_xCR_MAX,
  37 };
  38
  39 enum imx_mu_xsr {
  40         IMX_MU_SR,
  41         IMX_MU_GSR,
  42         IMX_MU_TSR,
  43         IMX_MU_RSR,
  44         IMX_MU_xSR_MAX
  45 };
  46
  47 enum imx_mu_type {
  48         IMX_MU_V2 = BIT(1),
  49 };
  50
  51 /* Receive Interrupt Enable */
  52 #define IMX_MU_xCR_RIEn(data, x) ((data->cfg->type) & IMX_MU_V2 ? BIT(x) : BIT(24 + (3 - (x))))
  53 #define IMX_MU_xSR_RFn(data, x) ((data->cfg->type) & IMX_MU_V2 ? BIT(x) : BIT(24 + (3 - (x))))
  54
  55 struct imx_mu_dcfg {
  56         enum imx_mu_type type;
  57         u32     xTR;            /* Transmit Register0 */
  58         u32     xRR;            /* Receive Register0 */
  59         u32     xSR[IMX_MU_xSR_MAX];         /* Status Registers */
  60         u32     xCR[IMX_MU_xCR_MAX];         /* Control Registers */
  61 };
  62
  63 struct imx_mu_msi {
  64         raw_spinlock_t                  lock;
  65         struct irq_domain               *msi_domain;
  66         void __iomem                    *regs;
  67         phys_addr_t                     msiir_addr;
  68         const struct imx_mu_dcfg        *cfg;
  69         unsigned long                   used;
  70         struct clk                      *clk;
  71 };
  72
  73 static void imx_mu_write(struct imx_mu_msi *msi_data, u32 val, u32 offs)
  74 {
  75         iowrite32(val, msi_data->regs + offs);
  76 }
  77
  78 static u32 imx_mu_read(struct imx_mu_msi *msi_data, u32 offs)
  79 {
  80         return ioread32(msi_data->regs + offs);
  81 }
  82
  83 static u32 imx_mu_xcr_rmw(struct imx_mu_msi *msi_data, enum imx_mu_xcr type, u32 set, u32 clr)
  84 {
  85         unsigned long flags;
  86         u32 val;
  87
  88         raw_spin_lock_irqsave(&msi_data->lock, flags);
  89         val = imx_mu_read(msi_data, msi_data->cfg->xCR[type]);
  90         val &= ~clr;
  91         val |= set;
  92         imx_mu_write(msi_data, val, msi_data->cfg->xCR[type]);
  93         raw_spin_unlock_irqrestore(&msi_data->lock, flags);
  94
  95         return val;
  96 }
  97
  98 static void imx_mu_msi_parent_mask_irq(struct irq_data *data)
  99 {
 100         struct imx_mu_msi *msi_data = irq_data_get_irq_chip_data(data);
 101
 102         imx_mu_xcr_rmw(msi_data, IMX_MU_RCR, 0, IMX_MU_xCR_RIEn(msi_data, data->hwirq));
 103 }
 104
 105 static void imx_mu_msi_parent_unmask_irq(struct irq_data *data)
 106 {
 107         struct imx_mu_msi *msi_data = irq_data_get_irq_chip_data(data);
 108
 109         imx_mu_xcr_rmw(msi_data, IMX_MU_RCR, IMX_MU_xCR_RIEn(msi_data, data->hwirq), 0);
 110 }
 111
 112 static void imx_mu_msi_parent_ack_irq(struct irq_data *data)
 113 {
 114         struct imx_mu_msi *msi_data = irq_data_get_irq_chip_data(data);
 115
 116         imx_mu_read(msi_data, msi_data->cfg->xRR + data->hwirq * 4);
 117 }
 118
 119 static void imx_mu_msi_parent_compose_msg(struct irq_data *data,
 120                                           struct msi_msg *msg)
 121 {
 122         struct imx_mu_msi *msi_data = irq_data_get_irq_chip_data(data);
 123         u64 addr = msi_data->msiir_addr + 4 * data->hwirq;
 124
 125         msg->address_hi = upper_32_bits(addr);
 126         msg->address_lo = lower_32_bits(addr);
 127         msg->data = data->hwirq;
 128 }
 129
 130 static int imx_mu_msi_parent_set_affinity(struct irq_data *irq_data,
 131                                    const struct cpumask *mask, bool force)
 132 {
 133         return -EINVAL;
 134 }
 135
 136 static struct irq_chip imx_mu_msi_parent_chip = {
 137         .name           = "MU",
 138         .irq_mask       = imx_mu_msi_parent_mask_irq,
 139         .irq_unmask     = imx_mu_msi_parent_unmask_irq,
 140         .irq_ack        = imx_mu_msi_parent_ack_irq,
 141         .irq_compose_msi_msg    = imx_mu_msi_parent_compose_msg,
 142         .irq_set_affinity = imx_mu_msi_parent_set_affinity,
 143 };
 144
 145 static int imx_mu_msi_domain_irq_alloc(struct irq_domain *domain,
 146                                         unsigned int virq,
 147                                         unsigned int nr_irqs,
 148                                         void *args)
 149 {
 150         struct imx_mu_msi *msi_data = domain->host_data;
 151         unsigned long flags;
 152         int pos, err = 0;
 153
 154         WARN_ON(nr_irqs != 1);
 155
 156         raw_spin_lock_irqsave(&msi_data->lock, flags);
 157         pos = find_first_zero_bit(&msi_data->used, IMX_MU_CHANS);
 158         if (pos < IMX_MU_CHANS)
 159                 __set_bit(pos, &msi_data->used);
 160         else
 161                 err = -ENOSPC;
 162         raw_spin_unlock_irqrestore(&msi_data->lock, flags);
 163
 164         if (err)
 165                 return err;
 166
 167         irq_domain_set_info(domain, virq, pos,
 168                             &imx_mu_msi_parent_chip, msi_data,
 169                             handle_edge_irq, NULL, NULL);
 170         return 0;
 171 }
 172
 173 static void imx_mu_msi_domain_irq_free(struct irq_domain *domain,
 174                                        unsigned int virq, unsigned int nr_irqs)
 175 {
 176         struct irq_data *d = irq_domain_get_irq_data(domain, virq);
 177         struct imx_mu_msi *msi_data = irq_data_get_irq_chip_data(d);
 178         unsigned long flags;
 179
 180         raw_spin_lock_irqsave(&msi_data->lock, flags);
 181         __clear_bit(d->hwirq, &msi_data->used);
 182         raw_spin_unlock_irqrestore(&msi_data->lock, flags);
 183 }
 184
 185 static const struct irq_domain_ops imx_mu_msi_domain_ops = {
 186         .select = msi_lib_irq_domain_select,
 187         .alloc  = imx_mu_msi_domain_irq_alloc,
 188         .free   = imx_mu_msi_domain_irq_free,
 189 };
 190
 191 static void imx_mu_msi_irq_handler(struct irq_desc *desc)
 192 {
 193         struct imx_mu_msi *msi_data = irq_desc_get_handler_data(desc);
 194         struct irq_chip *chip = irq_desc_get_chip(desc);
 195         u32 status;
 196         int i;
 197
 198         status = imx_mu_read(msi_data, msi_data->cfg->xSR[IMX_MU_RSR]);
 199
 200         chained_irq_enter(chip, desc);
 201         for (i = 0; i < IMX_MU_CHANS; i++) {
 202                 if (status & IMX_MU_xSR_RFn(msi_data, i))
 203                         generic_handle_domain_irq(msi_data->msi_domain, i);
 204         }
 205         chained_irq_exit(chip, desc);
 206 }
 207
 208 #define IMX_MU_MSI_FLAGS_REQUIRED       (MSI_FLAG_USE_DEF_DOM_OPS |     \
 209                                          MSI_FLAG_USE_DEF_CHIP_OPS |    \
 210                                          MSI_FLAG_PARENT_PM_DEV)
 211
 212 #define IMX_MU_MSI_FLAGS_SUPPORTED      (MSI_GENERIC_FLAGS_MASK)
 213
 214 static const struct msi_parent_ops imx_mu_msi_parent_ops = {
 215         .supported_flags        = IMX_MU_MSI_FLAGS_SUPPORTED,
 216         .required_flags         = IMX_MU_MSI_FLAGS_REQUIRED,
 217         .bus_select_token       = DOMAIN_BUS_NEXUS,
 218         .bus_select_mask        = MATCH_PLATFORM_MSI,
 219         .prefix                 = "MU-MSI-",
 220         .init_dev_msi_info      = msi_lib_init_dev_msi_info,
 221 };
 222
 223 static int imx_mu_msi_domains_init(struct imx_mu_msi *msi_data, struct device *dev)
 224 {
 225         struct fwnode_handle *fwnodes = dev_fwnode(dev);
 226         struct irq_domain *parent;
 227
 228         /* Initialize MSI domain parent */
 229         parent = irq_domain_create_linear(fwnodes, IMX_MU_CHANS,
 230                                           &imx_mu_msi_domain_ops, msi_data);
 231         if (!parent) {
 232                 dev_err(dev, "failed to create IRQ domain\n");
 233                 return -ENOMEM;
 234         }
 235
 236         irq_domain_update_bus_token(parent, DOMAIN_BUS_NEXUS);
 237         parent->dev = parent->pm_dev = dev;
 238         parent->flags |= IRQ_DOMAIN_FLAG_MSI_PARENT;
 239         parent->msi_parent_ops = &imx_mu_msi_parent_ops;
 240         return 0;
 241 }
 242
 243 /* Register offset of different version MU IP */
 244 static const struct imx_mu_dcfg imx_mu_cfg_imx6sx = {
 245         .type   = 0,
 246         .xTR    = 0x0,
 247         .xRR    = 0x10,
 248         .xSR    = {
 249                         [IMX_MU_SR]  = 0x20,
 250                         [IMX_MU_GSR] = 0x20,
 251                         [IMX_MU_TSR] = 0x20,
 252                         [IMX_MU_RSR] = 0x20,
 253                   },
 254         .xCR    = {
 255                         [IMX_MU_GIER] = 0x24,
 256                         [IMX_MU_GCR]  = 0x24,
 257                         [IMX_MU_TCR]  = 0x24,
 258                         [IMX_MU_RCR]  = 0x24,
 259                   },
 260 };
 261
 262 static const struct imx_mu_dcfg imx_mu_cfg_imx7ulp = {
 263         .type   = 0,
 264         .xTR    = 0x20,
 265         .xRR    = 0x40,
 266         .xSR    = {
 267                         [IMX_MU_SR]  = 0x60,
 268                         [IMX_MU_GSR] = 0x60,
 269                         [IMX_MU_TSR] = 0x60,
 270                         [IMX_MU_RSR] = 0x60,
 271                   },
 272         .xCR    = {
 273                         [IMX_MU_GIER] = 0x64,
 274                         [IMX_MU_GCR]  = 0x64,
 275                         [IMX_MU_TCR]  = 0x64,
 276                         [IMX_MU_RCR]  = 0x64,
 277                   },
 278 };
 279
 280 static const struct imx_mu_dcfg imx_mu_cfg_imx8ulp = {
 281         .type   = IMX_MU_V2,
 282         .xTR    = 0x200,
 283         .xRR    = 0x280,
 284         .xSR    = {
 285                         [IMX_MU_SR]  = 0xC,
 286                         [IMX_MU_GSR] = 0x118,
 287                         [IMX_MU_TSR] = 0x124,
 288                         [IMX_MU_RSR] = 0x12C,
 289                   },
 290         .xCR    = {
 291                         [IMX_MU_GIER] = 0x110,
 292                         [IMX_MU_GCR]  = 0x114,
 293                         [IMX_MU_TCR]  = 0x120,
 294                         [IMX_MU_RCR]  = 0x128
 295                   },
 296 };
 297
 298 static int __init imx_mu_of_init(struct device_node *dn,
 299                                  struct device_node *parent,
 300                                  const struct imx_mu_dcfg *cfg)
 301 {
 302         struct platform_device *pdev = of_find_device_by_node(dn);
 303         struct device_link *pd_link_a;
 304         struct device_link *pd_link_b;
 305         struct imx_mu_msi *msi_data;
 306         struct resource *res;
 307         struct device *pd_a;
 308         struct device *pd_b;
 309         struct device *dev;
 310         int ret;
 311         int irq;
 312
 313         dev = &pdev->dev;
 314
 315         msi_data = devm_kzalloc(&pdev->dev, sizeof(*msi_data), GFP_KERNEL);
 316         if (!msi_data)
 317                 return -ENOMEM;
 318
 319         msi_data->cfg = cfg;
 320
 321         msi_data->regs = devm_platform_ioremap_resource_byname(pdev, "processor-a-side");
 322         if (IS_ERR(msi_data->regs)) {
 323                 dev_err(&pdev->dev, "failed to initialize 'regs'\n");
 324                 return PTR_ERR(msi_data->regs);
 325         }
 326
 327         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "processor-b-side");
 328         if (!res)
 329                 return -EIO;
 330
 331         msi_data->msiir_addr = res->start + msi_data->cfg->xTR;
 332
 333         irq = platform_get_irq(pdev, 0);
 334         if (irq < 0)
 335                 return irq;
 336
 337         platform_set_drvdata(pdev, msi_data);
 338
 339         msi_data->clk = devm_clk_get(dev, NULL);
 340         if (IS_ERR(msi_data->clk))
 341                 return PTR_ERR(msi_data->clk);
 342
 343         pd_a = dev_pm_domain_attach_by_name(dev, "processor-a-side");
 344         if (IS_ERR(pd_a))
 345                 return PTR_ERR(pd_a);
 346
 347         pd_b = dev_pm_domain_attach_by_name(dev, "processor-b-side");
 348         if (IS_ERR(pd_b))
 349                 return PTR_ERR(pd_b);
 350
 351         pd_link_a = device_link_add(dev, pd_a,
 352                         DL_FLAG_STATELESS |
 353                         DL_FLAG_PM_RUNTIME |
 354                         DL_FLAG_RPM_ACTIVE);
 355
 356         if (!pd_link_a) {
 357                 dev_err(dev, "Failed to add device_link to mu a.\n");
 358                 goto err_pd_a;
 359         }
 360
 361         pd_link_b = device_link_add(dev, pd_b,
 362                         DL_FLAG_STATELESS |
 363                         DL_FLAG_PM_RUNTIME |
 364                         DL_FLAG_RPM_ACTIVE);
 365
 366
 367         if (!pd_link_b) {
 368                 dev_err(dev, "Failed to add device_link to mu a.\n");
 369                 goto err_pd_b;
 370         }
 371
 372         ret = imx_mu_msi_domains_init(msi_data, dev);
 373         if (ret)
 374                 goto err_dm_init;
 375
 376         pm_runtime_enable(dev);
 377
 378         irq_set_chained_handler_and_data(irq,
 379                                          imx_mu_msi_irq_handler,
 380                                          msi_data);
 381
 382         return 0;
 383
 384 err_dm_init:
 385         device_link_remove(dev, pd_b);
 386 err_pd_b:
 387         device_link_remove(dev, pd_a);
 388 err_pd_a:
 389         return -EINVAL;
 390 }
 391
 392 static int __maybe_unused imx_mu_runtime_suspend(struct device *dev)
 393 {
 394         struct imx_mu_msi *priv = dev_get_drvdata(dev);
 395
 396         clk_disable_unprepare(priv->clk);
 397
 398         return 0;
 399 }
 400
 401 static int __maybe_unused imx_mu_runtime_resume(struct device *dev)
 402 {
 403         struct imx_mu_msi *priv = dev_get_drvdata(dev);
 404         int ret;
 405
 406         ret = clk_prepare_enable(priv->clk);
 407         if (ret)
 408                 dev_err(dev, "failed to enable clock\n");
 409
 410         return ret;
 411 }
 412
 413 static const struct dev_pm_ops imx_mu_pm_ops = {
 414         SET_RUNTIME_PM_OPS(imx_mu_runtime_suspend,
 415                            imx_mu_runtime_resume, NULL)
 416 };
 417
 418 static int __init imx_mu_imx7ulp_of_init(struct device_node *dn,
 419                                          struct device_node *parent)
 420 {
 421         return imx_mu_of_init(dn, parent, &imx_mu_cfg_imx7ulp);
 422 }
 423
 424 static int __init imx_mu_imx6sx_of_init(struct device_node *dn,
 425                                         struct device_node *parent)
 426 {
 427         return imx_mu_of_init(dn, parent, &imx_mu_cfg_imx6sx);
 428 }
 429
 430 static int __init imx_mu_imx8ulp_of_init(struct device_node *dn,
 431                                          struct device_node *parent)
 432 {
 433         return imx_mu_of_init(dn, parent, &imx_mu_cfg_imx8ulp);
 434 }
 435
 436 IRQCHIP_PLATFORM_DRIVER_BEGIN(imx_mu_msi)
 437 IRQCHIP_MATCH("fsl,imx7ulp-mu-msi", imx_mu_imx7ulp_of_init)
 438 IRQCHIP_MATCH("fsl,imx6sx-mu-msi", imx_mu_imx6sx_of_init)
 439 IRQCHIP_MATCH("fsl,imx8ulp-mu-msi", imx_mu_imx8ulp_of_init)
 440 IRQCHIP_PLATFORM_DRIVER_END(imx_mu_msi, .pm = &imx_mu_pm_ops)
 441
 442
 443 MODULE_AUTHOR("Frank Li <Frank.Li@nxp.com>");
 444 MODULE_DESCRIPTION("Freescale MU MSI controller driver");
 445 MODULE_LICENSE("GPL");