drivers/pci/host/pci-dra7xx.c

   1 /*
   2  * pcie-dra7xx - PCIe controller driver for TI DRA7xx SoCs
   3  *
   4  * Copyright (C) 2013-2014 Texas Instruments Incorporated - http://www.ti.com
   5  *
   6  * Authors: Kishon Vijay Abraham I <kishon@ti.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/delay.h>
  14 #include <linux/err.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/irq.h>
  17 #include <linux/irqdomain.h>
  18 #include <linux/kernel.h>
  19 #include <linux/module.h>
  20 #include <linux/of_gpio.h>
  21 #include <linux/pci.h>
  22 #include <linux/phy/phy.h>
  23 #include <linux/platform_device.h>
  24 #include <linux/pm_runtime.h>
  25 #include <linux/resource.h>
  26 #include <linux/types.h>
  27
  28 #include "pcie-designware.h"
  29
  30 /* PCIe controller wrapper DRA7XX configuration registers */
  31
  32 #define PCIECTRL_DRA7XX_CONF_IRQSTATUS_MAIN             0x0024
  33 #define PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MAIN         0x0028
  34 #define ERR_SYS                                         BIT(0)
  35 #define ERR_FATAL                                       BIT(1)
  36 #define ERR_NONFATAL                                    BIT(2)
  37 #define ERR_COR                                         BIT(3)
  38 #define ERR_AXI                                         BIT(4)
  39 #define ERR_ECRC                                        BIT(5)
  40 #define PME_TURN_OFF                                    BIT(8)
  41 #define PME_TO_ACK                                      BIT(9)
  42 #define PM_PME                                          BIT(10)
  43 #define LINK_REQ_RST                                    BIT(11)
  44 #define LINK_UP_EVT                                     BIT(12)
  45 #define CFG_BME_EVT                                     BIT(13)
  46 #define CFG_MSE_EVT                                     BIT(14)
  47 #define INTERRUPTS (ERR_SYS | ERR_FATAL | ERR_NONFATAL | ERR_COR | ERR_AXI | \
  48                         ERR_ECRC | PME_TURN_OFF | PME_TO_ACK | PM_PME | \
  49                         LINK_REQ_RST | LINK_UP_EVT | CFG_BME_EVT | CFG_MSE_EVT)
  50
  51 #define PCIECTRL_DRA7XX_CONF_IRQSTATUS_MSI              0x0034
  52 #define PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MSI          0x0038
  53 #define INTA                                            BIT(0)
  54 #define INTB                                            BIT(1)
  55 #define INTC                                            BIT(2)
  56 #define INTD                                            BIT(3)
  57 #define MSI                                             BIT(4)
  58 #define LEG_EP_INTERRUPTS (INTA | INTB | INTC | INTD)
  59
  60 #define PCIECTRL_DRA7XX_CONF_DEVICE_CMD                 0x0104
  61 #define LTSSM_EN                                        0x1
  62
  63 #define PCIECTRL_DRA7XX_CONF_PHY_CS                     0x010C
  64 #define LINK_UP                                         BIT(16)
  65 #define DRA7XX_CPU_TO_BUS_ADDR                          0x0FFFFFFF
  66
  67 struct dra7xx_pcie {
  68         void __iomem            *base;
  69         struct phy              **phy;
  70         int                     phy_count;
  71         struct device           *dev;
  72         struct pcie_port        pp;
  73 };
  74
  75 #define to_dra7xx_pcie(x)       container_of((x), struct dra7xx_pcie, pp)
  76
  77 static inline u32 dra7xx_pcie_readl(struct dra7xx_pcie *pcie, u32 offset)
  78 {
  79         return readl(pcie->base + offset);
  80 }
  81
  82 static inline void dra7xx_pcie_writel(struct dra7xx_pcie *pcie, u32 offset,
  83                                       u32 value)
  84 {
  85         writel(value, pcie->base + offset);
  86 }
  87
  88 static inline u32 dra7xx_pcie_readl_rc(struct pcie_port *pp, u32 offset)
  89 {
  90         return readl(pp->dbi_base + offset);
  91 }
  92
  93 static inline void dra7xx_pcie_writel_rc(struct pcie_port *pp, u32 offset,
  94                                          u32 value)
  95 {
  96         writel(value, pp->dbi_base + offset);
  97 }
  98
  99 static int dra7xx_pcie_link_up(struct pcie_port *pp)
 100 {
 101         struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);
 102         u32 reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_PHY_CS);
 103
 104         return !!(reg & LINK_UP);
 105 }
 106
 107 static int dra7xx_pcie_establish_link(struct pcie_port *pp)
 108 {
 109         struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);
 110         u32 reg;
 111         unsigned int retries;
 112
 113         if (dw_pcie_link_up(pp)) {
 114                 dev_err(pp->dev, "link is already up\n");
 115                 return 0;
 116         }
 117
 118         reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_DEVICE_CMD);
 119         reg |= LTSSM_EN;
 120         dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_DEVICE_CMD, reg);
 121
 122         for (retries = 0; retries < 1000; retries++) {
 123                 if (dw_pcie_link_up(pp))
 124                         return 0;
 125                 usleep_range(10, 20);
 126         }
 127
 128         dev_err(pp->dev, "link is not up\n");
 129         return -EINVAL;
 130 }
 131
 132 static void dra7xx_pcie_enable_interrupts(struct pcie_port *pp)
 133 {
 134         struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);
 135
 136         dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MAIN,
 137                            ~INTERRUPTS);
 138         dra7xx_pcie_writel(dra7xx,
 139                            PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MAIN, INTERRUPTS);
 140         dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MSI,
 141                            ~LEG_EP_INTERRUPTS & ~MSI);
 142
 143         if (IS_ENABLED(CONFIG_PCI_MSI))
 144                 dra7xx_pcie_writel(dra7xx,
 145                                    PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MSI, MSI);
 146         else
 147                 dra7xx_pcie_writel(dra7xx,
 148                                    PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MSI,
 149                                    LEG_EP_INTERRUPTS);
 150 }
 151
 152 static void dra7xx_pcie_host_init(struct pcie_port *pp)
 153 {
 154         dw_pcie_setup_rc(pp);
 155
 156         pp->io_base &= DRA7XX_CPU_TO_BUS_ADDR;
 157         pp->mem_base &= DRA7XX_CPU_TO_BUS_ADDR;
 158         pp->cfg0_base &= DRA7XX_CPU_TO_BUS_ADDR;
 159         pp->cfg1_base &= DRA7XX_CPU_TO_BUS_ADDR;
 160
 161         dra7xx_pcie_establish_link(pp);
 162         if (IS_ENABLED(CONFIG_PCI_MSI))
 163                 dw_pcie_msi_init(pp);
 164         dra7xx_pcie_enable_interrupts(pp);
 165 }
 166
 167 static struct pcie_host_ops dra7xx_pcie_host_ops = {
 168         .link_up = dra7xx_pcie_link_up,
 169         .host_init = dra7xx_pcie_host_init,
 170 };
 171
 172 static int dra7xx_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
 173                                 irq_hw_number_t hwirq)
 174 {
 175         irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_simple_irq);
 176         irq_set_chip_data(irq, domain->host_data);
 177
 178         return 0;
 179 }
 180
 181 static const struct irq_domain_ops intx_domain_ops = {
 182         .map = dra7xx_pcie_intx_map,
 183 };
 184
 185 static int dra7xx_pcie_init_irq_domain(struct pcie_port *pp)
 186 {
 187         struct device *dev = pp->dev;
 188         struct device_node *node = dev->of_node;
 189         struct device_node *pcie_intc_node =  of_get_next_child(node, NULL);
 190
 191         if (!pcie_intc_node) {
 192                 dev_err(dev, "No PCIe Intc node found\n");
 193                 return PTR_ERR(pcie_intc_node);
 194         }
 195
 196         pp->irq_domain = irq_domain_add_linear(pcie_intc_node, 4,
 197                                                &intx_domain_ops, pp);
 198         if (!pp->irq_domain) {
 199                 dev_err(dev, "Failed to get a INTx IRQ domain\n");
 200                 return PTR_ERR(pp->irq_domain);
 201         }
 202
 203         return 0;
 204 }
 205
 206 static irqreturn_t dra7xx_pcie_msi_irq_handler(int irq, void *arg)
 207 {
 208         struct pcie_port *pp = arg;
 209         struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);
 210         u32 reg;
 211
 212         reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MSI);
 213
 214         switch (reg) {
 215         case MSI:
 216                 dw_handle_msi_irq(pp);
 217                 break;
 218         case INTA:
 219         case INTB:
 220         case INTC:
 221         case INTD:
 222                 generic_handle_irq(irq_find_mapping(pp->irq_domain, ffs(reg)));
 223                 break;
 224         }
 225
 226         dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MSI, reg);
 227
 228         return IRQ_HANDLED;
 229 }
 230
 231
 232 static irqreturn_t dra7xx_pcie_irq_handler(int irq, void *arg)
 233 {
 234         struct dra7xx_pcie *dra7xx = arg;
 235         u32 reg;
 236
 237         reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MAIN);
 238
 239         if (reg & ERR_SYS)
 240                 dev_dbg(dra7xx->dev, "System Error\n");
 241
 242         if (reg & ERR_FATAL)
 243                 dev_dbg(dra7xx->dev, "Fatal Error\n");
 244
 245         if (reg & ERR_NONFATAL)
 246                 dev_dbg(dra7xx->dev, "Non Fatal Error\n");
 247
 248         if (reg & ERR_COR)
 249                 dev_dbg(dra7xx->dev, "Correctable Error\n");
 250
 251         if (reg & ERR_AXI)
 252                 dev_dbg(dra7xx->dev, "AXI tag lookup fatal Error\n");
 253
 254         if (reg & ERR_ECRC)
 255                 dev_dbg(dra7xx->dev, "ECRC Error\n");
 256
 257         if (reg & PME_TURN_OFF)
 258                 dev_dbg(dra7xx->dev,
 259                         "Power Management Event Turn-Off message received\n");
 260
 261         if (reg & PME_TO_ACK)
 262                 dev_dbg(dra7xx->dev,
 263                         "Power Management Turn-Off Ack message received\n");
 264
 265         if (reg & PM_PME)
 266                 dev_dbg(dra7xx->dev,
 267                         "PM Power Management Event message received\n");
 268
 269         if (reg & LINK_REQ_RST)
 270                 dev_dbg(dra7xx->dev, "Link Request Reset\n");
 271
 272         if (reg & LINK_UP_EVT)
 273                 dev_dbg(dra7xx->dev, "Link-up state change\n");
 274
 275         if (reg & CFG_BME_EVT)
 276                 dev_dbg(dra7xx->dev, "CFG 'Bus Master Enable' change\n");
 277
 278         if (reg & CFG_MSE_EVT)
 279                 dev_dbg(dra7xx->dev, "CFG 'Memory Space Enable' change\n");
 280
 281         dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MAIN, reg);
 282
 283         return IRQ_HANDLED;
 284 }
 285
 286 static int __init dra7xx_add_pcie_port(struct dra7xx_pcie *dra7xx,
 287                                        struct platform_device *pdev)
 288 {
 289         int ret;
 290         struct pcie_port *pp;
 291         struct resource *res;
 292         struct device *dev = &pdev->dev;
 293
 294         pp = &dra7xx->pp;
 295         pp->dev = dev;
 296         pp->ops = &dra7xx_pcie_host_ops;
 297
 298         pp->irq = platform_get_irq(pdev, 1);
 299         if (pp->irq < 0) {
 300                 dev_err(dev, "missing IRQ resource\n");
 301                 return -EINVAL;
 302         }
 303
 304         ret = devm_request_irq(&pdev->dev, pp->irq,
 305                                dra7xx_pcie_msi_irq_handler, IRQF_SHARED,
 306                                "dra7-pcie-msi", pp);
 307         if (ret) {
 308                 dev_err(&pdev->dev, "failed to request irq\n");
 309                 return ret;
 310         }
 311
 312         if (!IS_ENABLED(CONFIG_PCI_MSI)) {
 313                 ret = dra7xx_pcie_init_irq_domain(pp);
 314                 if (ret < 0)
 315                         return ret;
 316         }
 317
 318         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "rc_dbics");
 319         pp->dbi_base = devm_ioremap(dev, res->start, resource_size(res));
 320         if (!pp->dbi_base)
 321                 return -ENOMEM;
 322
 323         ret = dw_pcie_host_init(pp);
 324         if (ret) {
 325                 dev_err(dra7xx->dev, "failed to initialize host\n");
 326                 return ret;
 327         }
 328
 329         return 0;
 330 }
 331
 332 static int __init dra7xx_pcie_probe(struct platform_device *pdev)
 333 {
 334         u32 reg;
 335         int ret;
 336         int irq;
 337         int i;
 338         int phy_count;
 339         struct phy **phy;
 340         void __iomem *base;
 341         struct resource *res;
 342         struct dra7xx_pcie *dra7xx;
 343         struct device *dev = &pdev->dev;
 344         struct device_node *np = dev->of_node;
 345         char name[10];
 346         int gpio_sel;
 347         enum of_gpio_flags flags;
 348         unsigned long gpio_flags;
 349
 350         dra7xx = devm_kzalloc(dev, sizeof(*dra7xx), GFP_KERNEL);
 351         if (!dra7xx)
 352                 return -ENOMEM;
 353
 354         irq = platform_get_irq(pdev, 0);
 355         if (irq < 0) {
 356                 dev_err(dev, "missing IRQ resource\n");
 357                 return -EINVAL;
 358         }
 359
 360         ret = devm_request_irq(dev, irq, dra7xx_pcie_irq_handler,
 361                                IRQF_SHARED, "dra7xx-pcie-main", dra7xx);
 362         if (ret) {
 363                 dev_err(dev, "failed to request irq\n");
 364                 return ret;
 365         }
 366
 367         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ti_conf");
 368         base = devm_ioremap_nocache(dev, res->start, resource_size(res));
 369         if (!base)
 370                 return -ENOMEM;
 371
 372         phy_count = of_property_count_strings(np, "phy-names");
 373         if (phy_count < 0) {
 374                 dev_err(dev, "unable to find the strings\n");
 375                 return phy_count;
 376         }
 377
 378         phy = devm_kzalloc(dev, sizeof(*phy) * phy_count, GFP_KERNEL);
 379         if (!phy)
 380                 return -ENOMEM;
 381
 382         for (i = 0; i < phy_count; i++) {
 383                 snprintf(name, sizeof(name), "pcie-phy%d", i);
 384                 phy[i] = devm_phy_get(dev, name);
 385                 if (IS_ERR(phy[i]))
 386                         return PTR_ERR(phy[i]);
 387
 388                 ret = phy_init(phy[i]);
 389                 if (ret < 0)
 390                         goto err_phy;
 391
 392                 ret = phy_power_on(phy[i]);
 393                 if (ret < 0) {
 394                         phy_exit(phy[i]);
 395                         goto err_phy;
 396                 }
 397         }
 398
 399         dra7xx->base = base;
 400         dra7xx->phy = phy;
 401         dra7xx->dev = dev;
 402         dra7xx->phy_count = phy_count;
 403
 404         pm_runtime_enable(dev);
 405         ret = pm_runtime_get_sync(dev);
 406         if (ret < 0) {
 407                 dev_err(dev, "pm_runtime_get_sync failed\n");
 408                 goto err_get_sync;
 409         }
 410
 411         gpio_sel = of_get_gpio_flags(dev->of_node, 0, &flags);
 412         if (gpio_is_valid(gpio_sel)) {
 413                 gpio_flags = (flags & OF_GPIO_ACTIVE_LOW) ?
 414                                 GPIOF_OUT_INIT_LOW : GPIOF_OUT_INIT_HIGH;
 415                 ret = devm_gpio_request_one(dev, gpio_sel, gpio_flags,
 416                                             "pcie_reset");
 417                 if (ret) {
 418                         dev_err(&pdev->dev, "gpio%d request failed, ret %d\n",
 419                                 gpio_sel, ret);
 420                         goto err_gpio;
 421                 }
 422         } else if (gpio_sel == -EPROBE_DEFER) {
 423                 ret = -EPROBE_DEFER;
 424                 goto err_gpio;
 425         }
 426
 427         reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_DEVICE_CMD);
 428         reg &= ~LTSSM_EN;
 429         dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_DEVICE_CMD, reg);
 430
 431         platform_set_drvdata(pdev, dra7xx);
 432
 433         ret = dra7xx_add_pcie_port(dra7xx, pdev);
 434         if (ret < 0)
 435                 goto err_gpio;
 436
 437         return 0;
 438
 439 err_gpio:
 440         pm_runtime_put(dev);
 441
 442 err_get_sync:
 443         pm_runtime_disable(dev);
 444
 445 err_phy:
 446         while (--i >= 0) {
 447                 phy_power_off(phy[i]);
 448                 phy_exit(phy[i]);
 449         }
 450
 451         return ret;
 452 }
 453
 454 static int __exit dra7xx_pcie_remove(struct platform_device *pdev)
 455 {
 456         struct dra7xx_pcie *dra7xx = platform_get_drvdata(pdev);
 457         struct pcie_port *pp = &dra7xx->pp;
 458         struct device *dev = &pdev->dev;
 459         int count = dra7xx->phy_count;
 460
 461         if (pp->irq_domain)
 462                 irq_domain_remove(pp->irq_domain);
 463         pm_runtime_put(dev);
 464         pm_runtime_disable(dev);
 465         while (count--) {
 466                 phy_power_off(dra7xx->phy[count]);
 467                 phy_exit(dra7xx->phy[count]);
 468         }
 469
 470         return 0;
 471 }
 472
 473 #ifdef CONFIG_PM_SLEEP
 474 static int dra7xx_pcie_suspend(struct device *dev)
 475 {
 476         struct dra7xx_pcie *dra7xx = dev_get_drvdata(dev);
 477         struct pcie_port *pp = &dra7xx->pp;
 478         u32 val;
 479
 480         /* clear MSE */
 481         val = dra7xx_pcie_readl_rc(pp, PCI_COMMAND);
 482         val &= ~PCI_COMMAND_MEMORY;
 483         dra7xx_pcie_writel_rc(pp, PCI_COMMAND, val);
 484
 485         return 0;
 486 }
 487
 488 static int dra7xx_pcie_resume(struct device *dev)
 489 {
 490         struct dra7xx_pcie *dra7xx = dev_get_drvdata(dev);
 491         struct pcie_port *pp = &dra7xx->pp;
 492         u32 val;
 493
 494         /* set MSE */
 495         val = dra7xx_pcie_readl_rc(pp, PCI_COMMAND);
 496         val |= PCI_COMMAND_MEMORY;
 497         dra7xx_pcie_writel_rc(pp, PCI_COMMAND, val);
 498
 499         return 0;
 500 }
 501
 502 static int dra7xx_pcie_suspend_noirq(struct device *dev)
 503 {
 504         struct dra7xx_pcie *dra7xx = dev_get_drvdata(dev);
 505         int count = dra7xx->phy_count;
 506
 507         while (count--) {
 508                 phy_power_off(dra7xx->phy[count]);
 509                 phy_exit(dra7xx->phy[count]);
 510         }
 511
 512         return 0;
 513 }
 514
 515 static int dra7xx_pcie_resume_noirq(struct device *dev)
 516 {
 517         struct dra7xx_pcie *dra7xx = dev_get_drvdata(dev);
 518         int phy_count = dra7xx->phy_count;
 519         int ret;
 520         int i;
 521
 522         for (i = 0; i < phy_count; i++) {
 523                 ret = phy_init(dra7xx->phy[i]);
 524                 if (ret < 0)
 525                         goto err_phy;
 526
 527                 ret = phy_power_on(dra7xx->phy[i]);
 528                 if (ret < 0) {
 529                         phy_exit(dra7xx->phy[i]);
 530                         goto err_phy;
 531                 }
 532         }
 533
 534         return 0;
 535
 536 err_phy:
 537         while (--i >= 0) {
 538                 phy_power_off(dra7xx->phy[i]);
 539                 phy_exit(dra7xx->phy[i]);
 540         }
 541
 542         return ret;
 543 }
 544 #endif
 545
 546 static const struct dev_pm_ops dra7xx_pcie_pm_ops = {
 547         SET_SYSTEM_SLEEP_PM_OPS(dra7xx_pcie_suspend, dra7xx_pcie_resume)
 548         SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(dra7xx_pcie_suspend_noirq,
 549                                       dra7xx_pcie_resume_noirq)
 550 };
 551
 552 static const struct of_device_id of_dra7xx_pcie_match[] = {
 553         { .compatible = "ti,dra7-pcie", },
 554         {},
 555 };
 556 MODULE_DEVICE_TABLE(of, of_dra7xx_pcie_match);
 557
 558 static struct platform_driver dra7xx_pcie_driver = {
 559         .remove         = __exit_p(dra7xx_pcie_remove),
 560         .driver = {
 561                 .name   = "dra7-pcie",
 562                 .of_match_table = of_dra7xx_pcie_match,
 563                 .pm     = &dra7xx_pcie_pm_ops,
 564         },
 565 };
 566
 567 module_platform_driver_probe(dra7xx_pcie_driver, dra7xx_pcie_probe);
 568
 569 MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>");
 570 MODULE_DESCRIPTION("TI PCIe controller driver");
 571 MODULE_LICENSE("GPL v2");