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/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
  65 struct dra7xx_pcie {
  66         void __iomem            *base;
  67         struct phy              **phy;
  68         int                     phy_count;
  69         struct device           *dev;
  70         struct pcie_port        pp;
  71 };
  72
  73 #define to_dra7xx_pcie(x)       container_of((x), struct dra7xx_pcie, pp)
  74
  75 static inline u32 dra7xx_pcie_readl(struct dra7xx_pcie *pcie, u32 offset)
  76 {
  77         return readl(pcie->base + offset);
  78 }
  79
  80 static inline void dra7xx_pcie_writel(struct dra7xx_pcie *pcie, u32 offset,
  81                                       u32 value)
  82 {
  83         writel(value, pcie->base + offset);
  84 }
  85
  86 static int dra7xx_pcie_link_up(struct pcie_port *pp)
  87 {
  88         struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);
  89         u32 reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_PHY_CS);
  90
  91         return !!(reg & LINK_UP);
  92 }
  93
  94 static int dra7xx_pcie_establish_link(struct pcie_port *pp)
  95 {
  96         struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);
  97         u32 reg;
  98         unsigned int retries;
  99
 100         if (dw_pcie_link_up(pp)) {
 101                 dev_err(pp->dev, "link is already up\n");
 102                 return 0;
 103         }
 104
 105         reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_DEVICE_CMD);
 106         reg |= LTSSM_EN;
 107         dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_DEVICE_CMD, reg);
 108
 109         for (retries = 0; retries < 1000; retries++) {
 110                 if (dw_pcie_link_up(pp))
 111                         return 0;
 112                 usleep_range(10, 20);
 113         }
 114
 115         dev_err(pp->dev, "link is not up\n");
 116         return -EINVAL;
 117 }
 118
 119 static void dra7xx_pcie_enable_interrupts(struct pcie_port *pp)
 120 {
 121         struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);
 122
 123         dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MAIN,
 124                            ~INTERRUPTS);
 125         dra7xx_pcie_writel(dra7xx,
 126                            PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MAIN, INTERRUPTS);
 127         dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MSI,
 128                            ~LEG_EP_INTERRUPTS & ~MSI);
 129
 130         if (IS_ENABLED(CONFIG_PCI_MSI))
 131                 dra7xx_pcie_writel(dra7xx,
 132                                    PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MSI, MSI);
 133         else
 134                 dra7xx_pcie_writel(dra7xx,
 135                                    PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MSI,
 136                                    LEG_EP_INTERRUPTS);
 137 }
 138
 139 static void dra7xx_pcie_host_init(struct pcie_port *pp)
 140 {
 141         dw_pcie_setup_rc(pp);
 142         dra7xx_pcie_establish_link(pp);
 143         if (IS_ENABLED(CONFIG_PCI_MSI))
 144                 dw_pcie_msi_init(pp);
 145         dra7xx_pcie_enable_interrupts(pp);
 146 }
 147
 148 static struct pcie_host_ops dra7xx_pcie_host_ops = {
 149         .link_up = dra7xx_pcie_link_up,
 150         .host_init = dra7xx_pcie_host_init,
 151 };
 152
 153 static int dra7xx_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
 154                                 irq_hw_number_t hwirq)
 155 {
 156         irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_simple_irq);
 157         irq_set_chip_data(irq, domain->host_data);
 158         set_irq_flags(irq, IRQF_VALID);
 159
 160         return 0;
 161 }
 162
 163 static const struct irq_domain_ops intx_domain_ops = {
 164         .map = dra7xx_pcie_intx_map,
 165 };
 166
 167 static int dra7xx_pcie_init_irq_domain(struct pcie_port *pp)
 168 {
 169         struct device *dev = pp->dev;
 170         struct device_node *node = dev->of_node;
 171         struct device_node *pcie_intc_node =  of_get_next_child(node, NULL);
 172
 173         if (!pcie_intc_node) {
 174                 dev_err(dev, "No PCIe Intc node found\n");
 175                 return PTR_ERR(pcie_intc_node);
 176         }
 177
 178         pp->irq_domain = irq_domain_add_linear(pcie_intc_node, 4,
 179                                                &intx_domain_ops, pp);
 180         if (!pp->irq_domain) {
 181                 dev_err(dev, "Failed to get a INTx IRQ domain\n");
 182                 return PTR_ERR(pp->irq_domain);
 183         }
 184
 185         return 0;
 186 }
 187
 188 static irqreturn_t dra7xx_pcie_msi_irq_handler(int irq, void *arg)
 189 {
 190         struct pcie_port *pp = arg;
 191         struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);
 192         u32 reg;
 193
 194         reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MSI);
 195
 196         switch (reg) {
 197         case MSI:
 198                 dw_handle_msi_irq(pp);
 199                 break;
 200         case INTA:
 201         case INTB:
 202         case INTC:
 203         case INTD:
 204                 generic_handle_irq(irq_find_mapping(pp->irq_domain, ffs(reg)));
 205                 break;
 206         }
 207
 208         dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MSI, reg);
 209
 210         return IRQ_HANDLED;
 211 }
 212
 213
 214 static irqreturn_t dra7xx_pcie_irq_handler(int irq, void *arg)
 215 {
 216         struct dra7xx_pcie *dra7xx = arg;
 217         u32 reg;
 218
 219         reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MAIN);
 220
 221         if (reg & ERR_SYS)
 222                 dev_dbg(dra7xx->dev, "System Error\n");
 223
 224         if (reg & ERR_FATAL)
 225                 dev_dbg(dra7xx->dev, "Fatal Error\n");
 226
 227         if (reg & ERR_NONFATAL)
 228                 dev_dbg(dra7xx->dev, "Non Fatal Error\n");
 229
 230         if (reg & ERR_COR)
 231                 dev_dbg(dra7xx->dev, "Correctable Error\n");
 232
 233         if (reg & ERR_AXI)
 234                 dev_dbg(dra7xx->dev, "AXI tag lookup fatal Error\n");
 235
 236         if (reg & ERR_ECRC)
 237                 dev_dbg(dra7xx->dev, "ECRC Error\n");
 238
 239         if (reg & PME_TURN_OFF)
 240                 dev_dbg(dra7xx->dev,
 241                         "Power Management Event Turn-Off message received\n");
 242
 243         if (reg & PME_TO_ACK)
 244                 dev_dbg(dra7xx->dev,
 245                         "Power Management Turn-Off Ack message received\n");
 246
 247         if (reg & PM_PME)
 248                 dev_dbg(dra7xx->dev,
 249                         "PM Power Management Event message received\n");
 250
 251         if (reg & LINK_REQ_RST)
 252                 dev_dbg(dra7xx->dev, "Link Request Reset\n");
 253
 254         if (reg & LINK_UP_EVT)
 255                 dev_dbg(dra7xx->dev, "Link-up state change\n");
 256
 257         if (reg & CFG_BME_EVT)
 258                 dev_dbg(dra7xx->dev, "CFG 'Bus Master Enable' change\n");
 259
 260         if (reg & CFG_MSE_EVT)
 261                 dev_dbg(dra7xx->dev, "CFG 'Memory Space Enable' change\n");
 262
 263         dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MAIN, reg);
 264
 265         return IRQ_HANDLED;
 266 }
 267
 268 static int __init dra7xx_add_pcie_port(struct dra7xx_pcie *dra7xx,
 269                                        struct platform_device *pdev)
 270 {
 271         int ret;
 272         struct pcie_port *pp;
 273         struct resource *res;
 274         struct device *dev = &pdev->dev;
 275
 276         pp = &dra7xx->pp;
 277         pp->dev = dev;
 278         pp->ops = &dra7xx_pcie_host_ops;
 279
 280         pp->irq = platform_get_irq(pdev, 1);
 281         if (pp->irq < 0) {
 282                 dev_err(dev, "missing IRQ resource\n");
 283                 return -EINVAL;
 284         }
 285
 286         ret = devm_request_irq(&pdev->dev, pp->irq,
 287                                dra7xx_pcie_msi_irq_handler, IRQF_SHARED,
 288                                "dra7-pcie-msi", pp);
 289         if (ret) {
 290                 dev_err(&pdev->dev, "failed to request irq\n");
 291                 return ret;
 292         }
 293
 294         if (!IS_ENABLED(CONFIG_PCI_MSI)) {
 295                 ret = dra7xx_pcie_init_irq_domain(pp);
 296                 if (ret < 0)
 297                         return ret;
 298         }
 299
 300         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "rc_dbics");
 301         pp->dbi_base = devm_ioremap(dev, res->start, resource_size(res));
 302         if (!pp->dbi_base)
 303                 return -ENOMEM;
 304
 305         ret = dw_pcie_host_init(pp);
 306         if (ret) {
 307                 dev_err(dra7xx->dev, "failed to initialize host\n");
 308                 return ret;
 309         }
 310
 311         return 0;
 312 }
 313
 314 static int __init dra7xx_pcie_probe(struct platform_device *pdev)
 315 {
 316         u32 reg;
 317         int ret;
 318         int irq;
 319         int i;
 320         int phy_count;
 321         struct phy **phy;
 322         void __iomem *base;
 323         struct resource *res;
 324         struct dra7xx_pcie *dra7xx;
 325         struct device *dev = &pdev->dev;
 326         struct device_node *np = dev->of_node;
 327         char name[10];
 328
 329         dra7xx = devm_kzalloc(dev, sizeof(*dra7xx), GFP_KERNEL);
 330         if (!dra7xx)
 331                 return -ENOMEM;
 332
 333         irq = platform_get_irq(pdev, 0);
 334         if (irq < 0) {
 335                 dev_err(dev, "missing IRQ resource\n");
 336                 return -EINVAL;
 337         }
 338
 339         ret = devm_request_irq(dev, irq, dra7xx_pcie_irq_handler,
 340                                IRQF_SHARED, "dra7xx-pcie-main", dra7xx);
 341         if (ret) {
 342                 dev_err(dev, "failed to request irq\n");
 343                 return ret;
 344         }
 345
 346         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ti_conf");
 347         base = devm_ioremap_nocache(dev, res->start, resource_size(res));
 348         if (!base)
 349                 return -ENOMEM;
 350
 351         phy_count = of_property_count_strings(np, "phy-names");
 352         if (phy_count < 0) {
 353                 dev_err(dev, "unable to find the strings\n");
 354                 return phy_count;
 355         }
 356
 357         phy = devm_kzalloc(dev, sizeof(*phy) * phy_count, GFP_KERNEL);
 358         if (!phy)
 359                 return -ENOMEM;
 360
 361         for (i = 0; i < phy_count; i++) {
 362                 snprintf(name, sizeof(name), "pcie-phy%d", i);
 363                 phy[i] = devm_phy_get(dev, name);
 364                 if (IS_ERR(phy[i]))
 365                         return PTR_ERR(phy[i]);
 366
 367                 ret = phy_init(phy[i]);
 368                 if (ret < 0)
 369                         goto err_phy;
 370
 371                 ret = phy_power_on(phy[i]);
 372                 if (ret < 0) {
 373                         phy_exit(phy[i]);
 374                         goto err_phy;
 375                 }
 376         }
 377
 378         dra7xx->base = base;
 379         dra7xx->phy = phy;
 380         dra7xx->dev = dev;
 381         dra7xx->phy_count = phy_count;
 382
 383         pm_runtime_enable(dev);
 384         ret = pm_runtime_get_sync(dev);
 385         if (IS_ERR_VALUE(ret)) {
 386                 dev_err(dev, "pm_runtime_get_sync failed\n");
 387                 goto err_phy;
 388         }
 389
 390         reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_DEVICE_CMD);
 391         reg &= ~LTSSM_EN;
 392         dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_DEVICE_CMD, reg);
 393
 394         platform_set_drvdata(pdev, dra7xx);
 395
 396         ret = dra7xx_add_pcie_port(dra7xx, pdev);
 397         if (ret < 0)
 398                 goto err_add_port;
 399
 400         return 0;
 401
 402 err_add_port:
 403         pm_runtime_put(dev);
 404         pm_runtime_disable(dev);
 405
 406 err_phy:
 407         while (--i >= 0) {
 408                 phy_power_off(phy[i]);
 409                 phy_exit(phy[i]);
 410         }
 411
 412         return ret;
 413 }
 414
 415 static int __exit dra7xx_pcie_remove(struct platform_device *pdev)
 416 {
 417         struct dra7xx_pcie *dra7xx = platform_get_drvdata(pdev);
 418         struct pcie_port *pp = &dra7xx->pp;
 419         struct device *dev = &pdev->dev;
 420         int count = dra7xx->phy_count;
 421
 422         if (pp->irq_domain)
 423                 irq_domain_remove(pp->irq_domain);
 424         pm_runtime_put(dev);
 425         pm_runtime_disable(dev);
 426         while (count--) {
 427                 phy_power_off(dra7xx->phy[count]);
 428                 phy_exit(dra7xx->phy[count]);
 429         }
 430
 431         return 0;
 432 }
 433
 434 static const struct of_device_id of_dra7xx_pcie_match[] = {
 435         { .compatible = "ti,dra7-pcie", },
 436         {},
 437 };
 438 MODULE_DEVICE_TABLE(of, of_dra7xx_pcie_match);
 439
 440 static struct platform_driver dra7xx_pcie_driver = {
 441         .remove         = __exit_p(dra7xx_pcie_remove),
 442         .driver = {
 443                 .name   = "dra7-pcie",
 444                 .of_match_table = of_dra7xx_pcie_match,
 445         },
 446 };
 447
 448 module_platform_driver_probe(dra7xx_pcie_driver, dra7xx_pcie_probe);
 449
 450 MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>");
 451 MODULE_DESCRIPTION("TI PCIe controller driver");
 452 MODULE_LICENSE("GPL v2");