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         u32 reg;
  97         unsigned int retries = 1000;
  98         struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);
  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         while (retries--) {
 110                 reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_PHY_CS);
 111                 if (reg & LINK_UP)
 112                         break;
 113                 usleep_range(10, 20);
 114         }
 115
 116         if (retries == 0) {
 117                 dev_err(pp->dev, "link is not up\n");
 118                 return -ETIMEDOUT;
 119         }
 120
 121         return 0;
 122 }
 123
 124 static void dra7xx_pcie_enable_interrupts(struct pcie_port *pp)
 125 {
 126         struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);
 127
 128         dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MAIN,
 129                            ~INTERRUPTS);
 130         dra7xx_pcie_writel(dra7xx,
 131                            PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MAIN, INTERRUPTS);
 132         dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MSI,
 133                            ~LEG_EP_INTERRUPTS & ~MSI);
 134
 135         if (IS_ENABLED(CONFIG_PCI_MSI))
 136                 dra7xx_pcie_writel(dra7xx,
 137                                    PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MSI, MSI);
 138         else
 139                 dra7xx_pcie_writel(dra7xx,
 140                                    PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MSI,
 141                                    LEG_EP_INTERRUPTS);
 142 }
 143
 144 static void dra7xx_pcie_host_init(struct pcie_port *pp)
 145 {
 146         dw_pcie_setup_rc(pp);
 147         dra7xx_pcie_establish_link(pp);
 148         if (IS_ENABLED(CONFIG_PCI_MSI))
 149                 dw_pcie_msi_init(pp);
 150         dra7xx_pcie_enable_interrupts(pp);
 151 }
 152
 153 static struct pcie_host_ops dra7xx_pcie_host_ops = {
 154         .link_up = dra7xx_pcie_link_up,
 155         .host_init = dra7xx_pcie_host_init,
 156 };
 157
 158 static int dra7xx_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
 159                                 irq_hw_number_t hwirq)
 160 {
 161         irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_simple_irq);
 162         irq_set_chip_data(irq, domain->host_data);
 163         set_irq_flags(irq, IRQF_VALID);
 164
 165         return 0;
 166 }
 167
 168 static const struct irq_domain_ops intx_domain_ops = {
 169         .map = dra7xx_pcie_intx_map,
 170 };
 171
 172 static int dra7xx_pcie_init_irq_domain(struct pcie_port *pp)
 173 {
 174         struct device *dev = pp->dev;
 175         struct device_node *node = dev->of_node;
 176         struct device_node *pcie_intc_node =  of_get_next_child(node, NULL);
 177
 178         if (!pcie_intc_node) {
 179                 dev_err(dev, "No PCIe Intc node found\n");
 180                 return PTR_ERR(pcie_intc_node);
 181         }
 182
 183         pp->irq_domain = irq_domain_add_linear(pcie_intc_node, 4,
 184                                                &intx_domain_ops, pp);
 185         if (!pp->irq_domain) {
 186                 dev_err(dev, "Failed to get a INTx IRQ domain\n");
 187                 return PTR_ERR(pp->irq_domain);
 188         }
 189
 190         return 0;
 191 }
 192
 193 static irqreturn_t dra7xx_pcie_msi_irq_handler(int irq, void *arg)
 194 {
 195         struct pcie_port *pp = arg;
 196         struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);
 197         u32 reg;
 198
 199         reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MSI);
 200
 201         switch (reg) {
 202         case MSI:
 203                 dw_handle_msi_irq(pp);
 204                 break;
 205         case INTA:
 206         case INTB:
 207         case INTC:
 208         case INTD:
 209                 generic_handle_irq(irq_find_mapping(pp->irq_domain, ffs(reg)));
 210                 break;
 211         }
 212
 213         dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MSI, reg);
 214
 215         return IRQ_HANDLED;
 216 }
 217
 218
 219 static irqreturn_t dra7xx_pcie_irq_handler(int irq, void *arg)
 220 {
 221         struct dra7xx_pcie *dra7xx = arg;
 222         u32 reg;
 223
 224         reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MAIN);
 225
 226         if (reg & ERR_SYS)
 227                 dev_dbg(dra7xx->dev, "System Error\n");
 228
 229         if (reg & ERR_FATAL)
 230                 dev_dbg(dra7xx->dev, "Fatal Error\n");
 231
 232         if (reg & ERR_NONFATAL)
 233                 dev_dbg(dra7xx->dev, "Non Fatal Error\n");
 234
 235         if (reg & ERR_COR)
 236                 dev_dbg(dra7xx->dev, "Correctable Error\n");
 237
 238         if (reg & ERR_AXI)
 239                 dev_dbg(dra7xx->dev, "AXI tag lookup fatal Error\n");
 240
 241         if (reg & ERR_ECRC)
 242                 dev_dbg(dra7xx->dev, "ECRC Error\n");
 243
 244         if (reg & PME_TURN_OFF)
 245                 dev_dbg(dra7xx->dev,
 246                         "Power Management Event Turn-Off message received\n");
 247
 248         if (reg & PME_TO_ACK)
 249                 dev_dbg(dra7xx->dev,
 250                         "Power Management Turn-Off Ack message received\n");
 251
 252         if (reg & PM_PME)
 253                 dev_dbg(dra7xx->dev,
 254                         "PM Power Management Event message received\n");
 255
 256         if (reg & LINK_REQ_RST)
 257                 dev_dbg(dra7xx->dev, "Link Request Reset\n");
 258
 259         if (reg & LINK_UP_EVT)
 260                 dev_dbg(dra7xx->dev, "Link-up state change\n");
 261
 262         if (reg & CFG_BME_EVT)
 263                 dev_dbg(dra7xx->dev, "CFG 'Bus Master Enable' change\n");
 264
 265         if (reg & CFG_MSE_EVT)
 266                 dev_dbg(dra7xx->dev, "CFG 'Memory Space Enable' change\n");
 267
 268         dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MAIN, reg);
 269
 270         return IRQ_HANDLED;
 271 }
 272
 273 static int add_pcie_port(struct dra7xx_pcie *dra7xx,
 274                           struct platform_device *pdev)
 275 {
 276         int ret;
 277         struct pcie_port *pp;
 278         struct resource *res;
 279         struct device *dev = &pdev->dev;
 280
 281         pp = &dra7xx->pp;
 282         pp->dev = dev;
 283         pp->ops = &dra7xx_pcie_host_ops;
 284
 285         pp->irq = platform_get_irq(pdev, 1);
 286         if (pp->irq < 0) {
 287                 dev_err(dev, "missing IRQ resource\n");
 288                 return -EINVAL;
 289         }
 290
 291         ret = devm_request_irq(&pdev->dev, pp->irq,
 292                                dra7xx_pcie_msi_irq_handler, IRQF_SHARED,
 293                                "dra7-pcie-msi", pp);
 294         if (ret) {
 295                 dev_err(&pdev->dev, "failed to request irq\n");
 296                 return ret;
 297         }
 298
 299         if (!IS_ENABLED(CONFIG_PCI_MSI)) {
 300                 ret = dra7xx_pcie_init_irq_domain(pp);
 301                 if (ret < 0)
 302                         return ret;
 303         }
 304
 305         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "rc_dbics");
 306         pp->dbi_base = devm_ioremap(dev, res->start, resource_size(res));
 307         if (!pp->dbi_base)
 308                 return -ENOMEM;
 309
 310         ret = dw_pcie_host_init(pp);
 311         if (ret) {
 312                 dev_err(dra7xx->dev, "failed to initialize host\n");
 313                 return ret;
 314         }
 315
 316         return 0;
 317 }
 318
 319 static int __init dra7xx_pcie_probe(struct platform_device *pdev)
 320 {
 321         u32 reg;
 322         int ret;
 323         int irq;
 324         int i;
 325         int phy_count;
 326         struct phy **phy;
 327         void __iomem *base;
 328         struct resource *res;
 329         struct dra7xx_pcie *dra7xx;
 330         struct device *dev = &pdev->dev;
 331         struct device_node *np = dev->of_node;
 332         char name[10];
 333
 334         dra7xx = devm_kzalloc(dev, sizeof(*dra7xx), GFP_KERNEL);
 335         if (!dra7xx)
 336                 return -ENOMEM;
 337
 338         irq = platform_get_irq(pdev, 0);
 339         if (irq < 0) {
 340                 dev_err(dev, "missing IRQ resource\n");
 341                 return -EINVAL;
 342         }
 343
 344         ret = devm_request_irq(dev, irq, dra7xx_pcie_irq_handler,
 345                                IRQF_SHARED, "dra7xx-pcie-main", dra7xx);
 346         if (ret) {
 347                 dev_err(dev, "failed to request irq\n");
 348                 return ret;
 349         }
 350
 351         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ti_conf");
 352         base = devm_ioremap_nocache(dev, res->start, resource_size(res));
 353         if (!base)
 354                 return -ENOMEM;
 355
 356         phy_count = of_property_count_strings(np, "phy-names");
 357         if (phy_count < 0) {
 358                 dev_err(dev, "unable to find the strings\n");
 359                 return phy_count;
 360         }
 361
 362         phy = devm_kzalloc(dev, sizeof(*phy) * phy_count, GFP_KERNEL);
 363         if (!phy)
 364                 return -ENOMEM;
 365
 366         for (i = 0; i < phy_count; i++) {
 367                 snprintf(name, sizeof(name), "pcie-phy%d", i);
 368                 phy[i] = devm_phy_get(dev, name);
 369                 if (IS_ERR(phy[i]))
 370                         return PTR_ERR(phy[i]);
 371
 372                 ret = phy_init(phy[i]);
 373                 if (ret < 0)
 374                         goto err_phy;
 375
 376                 ret = phy_power_on(phy[i]);
 377                 if (ret < 0) {
 378                         phy_exit(phy[i]);
 379                         goto err_phy;
 380                 }
 381         }
 382
 383         dra7xx->base = base;
 384         dra7xx->phy = phy;
 385         dra7xx->dev = dev;
 386         dra7xx->phy_count = phy_count;
 387
 388         pm_runtime_enable(dev);
 389         ret = pm_runtime_get_sync(dev);
 390         if (IS_ERR_VALUE(ret)) {
 391                 dev_err(dev, "pm_runtime_get_sync failed\n");
 392                 goto err_phy;
 393         }
 394
 395         reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_DEVICE_CMD);
 396         reg &= ~LTSSM_EN;
 397         dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_DEVICE_CMD, reg);
 398
 399         platform_set_drvdata(pdev, dra7xx);
 400
 401         ret = add_pcie_port(dra7xx, pdev);
 402         if (ret < 0)
 403                 goto err_add_port;
 404
 405         return 0;
 406
 407 err_add_port:
 408         pm_runtime_put(dev);
 409         pm_runtime_disable(dev);
 410
 411 err_phy:
 412         while (--i >= 0) {
 413                 phy_power_off(phy[i]);
 414                 phy_exit(phy[i]);
 415         }
 416
 417         return ret;
 418 }
 419
 420 static int __exit dra7xx_pcie_remove(struct platform_device *pdev)
 421 {
 422         struct dra7xx_pcie *dra7xx = platform_get_drvdata(pdev);
 423         struct pcie_port *pp = &dra7xx->pp;
 424         struct device *dev = &pdev->dev;
 425         int count = dra7xx->phy_count;
 426
 427         if (pp->irq_domain)
 428                 irq_domain_remove(pp->irq_domain);
 429         pm_runtime_put(dev);
 430         pm_runtime_disable(dev);
 431         while (count--) {
 432                 phy_power_off(dra7xx->phy[count]);
 433                 phy_exit(dra7xx->phy[count]);
 434         }
 435
 436         return 0;
 437 }
 438
 439 static const struct of_device_id of_dra7xx_pcie_match[] = {
 440         { .compatible = "ti,dra7-pcie", },
 441         {},
 442 };
 443 MODULE_DEVICE_TABLE(of, of_dra7xx_pcie_match);
 444
 445 static struct platform_driver dra7xx_pcie_driver = {
 446         .remove         = __exit_p(dra7xx_pcie_remove),
 447         .driver = {
 448                 .name   = "dra7-pcie",
 449                 .owner  = THIS_MODULE,
 450                 .of_match_table = of_dra7xx_pcie_match,
 451         },
 452 };
 453
 454 module_platform_driver_probe(dra7xx_pcie_driver, dra7xx_pcie_probe);
 455
 456 MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>");
 457 MODULE_DESCRIPTION("TI PCIe controller driver");
 458 MODULE_LICENSE("GPL v2");