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