drivers/pci/host/pci-rcar-gen2.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  pci-rcar-gen2: internal PCI bus support
   4  *
   5  * Copyright (C) 2013 Renesas Solutions Corp.
   6  * Copyright (C) 2013 Cogent Embedded, Inc.
   7  *
   8  * Author: Valentine Barshak <valentine.barshak@cogentembedded.com>
   9  */
  10
  11 #include <linux/delay.h>
  12 #include <linux/init.h>
  13 #include <linux/interrupt.h>
  14 #include <linux/io.h>
  15 #include <linux/kernel.h>
  16 #include <linux/of_address.h>
  17 #include <linux/of_pci.h>
  18 #include <linux/pci.h>
  19 #include <linux/platform_device.h>
  20 #include <linux/pm_runtime.h>
  21 #include <linux/sizes.h>
  22 #include <linux/slab.h>
  23
  24 #include "../pci.h"
  25
  26 /* AHB-PCI Bridge PCI communication registers */
  27 #define RCAR_AHBPCI_PCICOM_OFFSET       0x800
  28
  29 #define RCAR_PCIAHB_WIN1_CTR_REG        (RCAR_AHBPCI_PCICOM_OFFSET + 0x00)
  30 #define RCAR_PCIAHB_WIN2_CTR_REG        (RCAR_AHBPCI_PCICOM_OFFSET + 0x04)
  31 #define RCAR_PCIAHB_PREFETCH0           0x0
  32 #define RCAR_PCIAHB_PREFETCH4           0x1
  33 #define RCAR_PCIAHB_PREFETCH8           0x2
  34 #define RCAR_PCIAHB_PREFETCH16          0x3
  35
  36 #define RCAR_AHBPCI_WIN1_CTR_REG        (RCAR_AHBPCI_PCICOM_OFFSET + 0x10)
  37 #define RCAR_AHBPCI_WIN2_CTR_REG        (RCAR_AHBPCI_PCICOM_OFFSET + 0x14)
  38 #define RCAR_AHBPCI_WIN_CTR_MEM         (3 << 1)
  39 #define RCAR_AHBPCI_WIN_CTR_CFG         (5 << 1)
  40 #define RCAR_AHBPCI_WIN1_HOST           (1 << 30)
  41 #define RCAR_AHBPCI_WIN1_DEVICE         (1 << 31)
  42
  43 #define RCAR_PCI_INT_ENABLE_REG         (RCAR_AHBPCI_PCICOM_OFFSET + 0x20)
  44 #define RCAR_PCI_INT_STATUS_REG         (RCAR_AHBPCI_PCICOM_OFFSET + 0x24)
  45 #define RCAR_PCI_INT_SIGTABORT          (1 << 0)
  46 #define RCAR_PCI_INT_SIGRETABORT        (1 << 1)
  47 #define RCAR_PCI_INT_REMABORT           (1 << 2)
  48 #define RCAR_PCI_INT_PERR               (1 << 3)
  49 #define RCAR_PCI_INT_SIGSERR            (1 << 4)
  50 #define RCAR_PCI_INT_RESERR             (1 << 5)
  51 #define RCAR_PCI_INT_WIN1ERR            (1 << 12)
  52 #define RCAR_PCI_INT_WIN2ERR            (1 << 13)
  53 #define RCAR_PCI_INT_A                  (1 << 16)
  54 #define RCAR_PCI_INT_B                  (1 << 17)
  55 #define RCAR_PCI_INT_PME                (1 << 19)
  56 #define RCAR_PCI_INT_ALLERRORS (RCAR_PCI_INT_SIGTABORT          | \
  57                                 RCAR_PCI_INT_SIGRETABORT        | \
  58                                 RCAR_PCI_INT_REMABORT           | \
  59                                 RCAR_PCI_INT_PERR               | \
  60                                 RCAR_PCI_INT_SIGSERR            | \
  61                                 RCAR_PCI_INT_RESERR             | \
  62                                 RCAR_PCI_INT_WIN1ERR            | \
  63                                 RCAR_PCI_INT_WIN2ERR)
  64
  65 #define RCAR_AHB_BUS_CTR_REG            (RCAR_AHBPCI_PCICOM_OFFSET + 0x30)
  66 #define RCAR_AHB_BUS_MMODE_HTRANS       (1 << 0)
  67 #define RCAR_AHB_BUS_MMODE_BYTE_BURST   (1 << 1)
  68 #define RCAR_AHB_BUS_MMODE_WR_INCR      (1 << 2)
  69 #define RCAR_AHB_BUS_MMODE_HBUS_REQ     (1 << 7)
  70 #define RCAR_AHB_BUS_SMODE_READYCTR     (1 << 17)
  71 #define RCAR_AHB_BUS_MODE               (RCAR_AHB_BUS_MMODE_HTRANS |    \
  72                                         RCAR_AHB_BUS_MMODE_BYTE_BURST | \
  73                                         RCAR_AHB_BUS_MMODE_WR_INCR |    \
  74                                         RCAR_AHB_BUS_MMODE_HBUS_REQ |   \
  75                                         RCAR_AHB_BUS_SMODE_READYCTR)
  76
  77 #define RCAR_USBCTR_REG                 (RCAR_AHBPCI_PCICOM_OFFSET + 0x34)
  78 #define RCAR_USBCTR_USBH_RST            (1 << 0)
  79 #define RCAR_USBCTR_PCICLK_MASK         (1 << 1)
  80 #define RCAR_USBCTR_PLL_RST             (1 << 2)
  81 #define RCAR_USBCTR_DIRPD               (1 << 8)
  82 #define RCAR_USBCTR_PCIAHB_WIN2_EN      (1 << 9)
  83 #define RCAR_USBCTR_PCIAHB_WIN1_256M    (0 << 10)
  84 #define RCAR_USBCTR_PCIAHB_WIN1_512M    (1 << 10)
  85 #define RCAR_USBCTR_PCIAHB_WIN1_1G      (2 << 10)
  86 #define RCAR_USBCTR_PCIAHB_WIN1_2G      (3 << 10)
  87 #define RCAR_USBCTR_PCIAHB_WIN1_MASK    (3 << 10)
  88
  89 #define RCAR_PCI_ARBITER_CTR_REG        (RCAR_AHBPCI_PCICOM_OFFSET + 0x40)
  90 #define RCAR_PCI_ARBITER_PCIREQ0        (1 << 0)
  91 #define RCAR_PCI_ARBITER_PCIREQ1        (1 << 1)
  92 #define RCAR_PCI_ARBITER_PCIBP_MODE     (1 << 12)
  93
  94 #define RCAR_PCI_UNIT_REV_REG           (RCAR_AHBPCI_PCICOM_OFFSET + 0x48)
  95
  96 struct rcar_pci_priv {
  97         struct device *dev;
  98         void __iomem *reg;
  99         struct resource mem_res;
 100         struct resource *cfg_res;
 101         unsigned busnr;
 102         int irq;
 103         unsigned long window_size;
 104         unsigned long window_addr;
 105         unsigned long window_pci;
 106 };
 107
 108 /* PCI configuration space operations */
 109 static void __iomem *rcar_pci_cfg_base(struct pci_bus *bus, unsigned int devfn,
 110                                        int where)
 111 {
 112         struct pci_sys_data *sys = bus->sysdata;
 113         struct rcar_pci_priv *priv = sys->private_data;
 114         int slot, val;
 115
 116         if (sys->busnr != bus->number || PCI_FUNC(devfn))
 117                 return NULL;
 118
 119         /* Only one EHCI/OHCI device built-in */
 120         slot = PCI_SLOT(devfn);
 121         if (slot > 2)
 122                 return NULL;
 123
 124         /* bridge logic only has registers to 0x40 */
 125         if (slot == 0x0 && where >= 0x40)
 126                 return NULL;
 127
 128         val = slot ? RCAR_AHBPCI_WIN1_DEVICE | RCAR_AHBPCI_WIN_CTR_CFG :
 129                      RCAR_AHBPCI_WIN1_HOST | RCAR_AHBPCI_WIN_CTR_CFG;
 130
 131         iowrite32(val, priv->reg + RCAR_AHBPCI_WIN1_CTR_REG);
 132         return priv->reg + (slot >> 1) * 0x100 + where;
 133 }
 134
 135 /* PCI interrupt mapping */
 136 static int rcar_pci_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
 137 {
 138         struct pci_sys_data *sys = dev->bus->sysdata;
 139         struct rcar_pci_priv *priv = sys->private_data;
 140         int irq;
 141
 142         irq = of_irq_parse_and_map_pci(dev, slot, pin);
 143         if (!irq)
 144                 irq = priv->irq;
 145
 146         return irq;
 147 }
 148
 149 #ifdef CONFIG_PCI_DEBUG
 150 /* if debug enabled, then attach an error handler irq to the bridge */
 151
 152 static irqreturn_t rcar_pci_err_irq(int irq, void *pw)
 153 {
 154         struct rcar_pci_priv *priv = pw;
 155         struct device *dev = priv->dev;
 156         u32 status = ioread32(priv->reg + RCAR_PCI_INT_STATUS_REG);
 157
 158         if (status & RCAR_PCI_INT_ALLERRORS) {
 159                 dev_err(dev, "error irq: status %08x\n", status);
 160
 161                 /* clear the error(s) */
 162                 iowrite32(status & RCAR_PCI_INT_ALLERRORS,
 163                           priv->reg + RCAR_PCI_INT_STATUS_REG);
 164                 return IRQ_HANDLED;
 165         }
 166
 167         return IRQ_NONE;
 168 }
 169
 170 static void rcar_pci_setup_errirq(struct rcar_pci_priv *priv)
 171 {
 172         struct device *dev = priv->dev;
 173         int ret;
 174         u32 val;
 175
 176         ret = devm_request_irq(dev, priv->irq, rcar_pci_err_irq,
 177                                IRQF_SHARED, "error irq", priv);
 178         if (ret) {
 179                 dev_err(dev, "cannot claim IRQ for error handling\n");
 180                 return;
 181         }
 182
 183         val = ioread32(priv->reg + RCAR_PCI_INT_ENABLE_REG);
 184         val |= RCAR_PCI_INT_ALLERRORS;
 185         iowrite32(val, priv->reg + RCAR_PCI_INT_ENABLE_REG);
 186 }
 187 #else
 188 static inline void rcar_pci_setup_errirq(struct rcar_pci_priv *priv) { }
 189 #endif
 190
 191 /* PCI host controller setup */
 192 static int rcar_pci_setup(int nr, struct pci_sys_data *sys)
 193 {
 194         struct rcar_pci_priv *priv = sys->private_data;
 195         struct device *dev = priv->dev;
 196         void __iomem *reg = priv->reg;
 197         u32 val;
 198         int ret;
 199
 200         pm_runtime_enable(dev);
 201         pm_runtime_get_sync(dev);
 202
 203         val = ioread32(reg + RCAR_PCI_UNIT_REV_REG);
 204         dev_info(dev, "PCI: bus%u revision %x\n", sys->busnr, val);
 205
 206         /* Disable Direct Power Down State and assert reset */
 207         val = ioread32(reg + RCAR_USBCTR_REG) & ~RCAR_USBCTR_DIRPD;
 208         val |= RCAR_USBCTR_USBH_RST | RCAR_USBCTR_PLL_RST;
 209         iowrite32(val, reg + RCAR_USBCTR_REG);
 210         udelay(4);
 211
 212         /* De-assert reset and reset PCIAHB window1 size */
 213         val &= ~(RCAR_USBCTR_PCIAHB_WIN1_MASK | RCAR_USBCTR_PCICLK_MASK |
 214                  RCAR_USBCTR_USBH_RST | RCAR_USBCTR_PLL_RST);
 215
 216         /* Setup PCIAHB window1 size */
 217         switch (priv->window_size) {
 218         case SZ_2G:
 219                 val |= RCAR_USBCTR_PCIAHB_WIN1_2G;
 220                 break;
 221         case SZ_1G:
 222                 val |= RCAR_USBCTR_PCIAHB_WIN1_1G;
 223                 break;
 224         case SZ_512M:
 225                 val |= RCAR_USBCTR_PCIAHB_WIN1_512M;
 226                 break;
 227         default:
 228                 pr_warn("unknown window size %ld - defaulting to 256M\n",
 229                         priv->window_size);
 230                 priv->window_size = SZ_256M;
 231                 /* fall-through */
 232         case SZ_256M:
 233                 val |= RCAR_USBCTR_PCIAHB_WIN1_256M;
 234                 break;
 235         }
 236         iowrite32(val, reg + RCAR_USBCTR_REG);
 237
 238         /* Configure AHB master and slave modes */
 239         iowrite32(RCAR_AHB_BUS_MODE, reg + RCAR_AHB_BUS_CTR_REG);
 240
 241         /* Configure PCI arbiter */
 242         val = ioread32(reg + RCAR_PCI_ARBITER_CTR_REG);
 243         val |= RCAR_PCI_ARBITER_PCIREQ0 | RCAR_PCI_ARBITER_PCIREQ1 |
 244                RCAR_PCI_ARBITER_PCIBP_MODE;
 245         iowrite32(val, reg + RCAR_PCI_ARBITER_CTR_REG);
 246
 247         /* PCI-AHB mapping */
 248         iowrite32(priv->window_addr | RCAR_PCIAHB_PREFETCH16,
 249                   reg + RCAR_PCIAHB_WIN1_CTR_REG);
 250
 251         /* AHB-PCI mapping: OHCI/EHCI registers */
 252         val = priv->mem_res.start | RCAR_AHBPCI_WIN_CTR_MEM;
 253         iowrite32(val, reg + RCAR_AHBPCI_WIN2_CTR_REG);
 254
 255         /* Enable AHB-PCI bridge PCI configuration access */
 256         iowrite32(RCAR_AHBPCI_WIN1_HOST | RCAR_AHBPCI_WIN_CTR_CFG,
 257                   reg + RCAR_AHBPCI_WIN1_CTR_REG);
 258         /* Set PCI-AHB Window1 address */
 259         iowrite32(priv->window_pci | PCI_BASE_ADDRESS_MEM_PREFETCH,
 260                   reg + PCI_BASE_ADDRESS_1);
 261         /* Set AHB-PCI bridge PCI communication area address */
 262         val = priv->cfg_res->start + RCAR_AHBPCI_PCICOM_OFFSET;
 263         iowrite32(val, reg + PCI_BASE_ADDRESS_0);
 264
 265         val = ioread32(reg + PCI_COMMAND);
 266         val |= PCI_COMMAND_SERR | PCI_COMMAND_PARITY |
 267                PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER;
 268         iowrite32(val, reg + PCI_COMMAND);
 269
 270         /* Enable PCI interrupts */
 271         iowrite32(RCAR_PCI_INT_A | RCAR_PCI_INT_B | RCAR_PCI_INT_PME,
 272                   reg + RCAR_PCI_INT_ENABLE_REG);
 273
 274         if (priv->irq > 0)
 275                 rcar_pci_setup_errirq(priv);
 276
 277         /* Add PCI resources */
 278         pci_add_resource(&sys->resources, &priv->mem_res);
 279         ret = devm_request_pci_bus_resources(dev, &sys->resources);
 280         if (ret < 0)
 281                 return ret;
 282
 283         /* Setup bus number based on platform device id / of bus-range */
 284         sys->busnr = priv->busnr;
 285         return 1;
 286 }
 287
 288 static struct pci_ops rcar_pci_ops = {
 289         .map_bus = rcar_pci_cfg_base,
 290         .read   = pci_generic_config_read,
 291         .write  = pci_generic_config_write,
 292 };
 293
 294 static int rcar_pci_parse_map_dma_ranges(struct rcar_pci_priv *pci,
 295                                          struct device_node *np)
 296 {
 297         struct device *dev = pci->dev;
 298         struct of_pci_range range;
 299         struct of_pci_range_parser parser;
 300         int index = 0;
 301
 302         /* Failure to parse is ok as we fall back to defaults */
 303         if (of_pci_dma_range_parser_init(&parser, np))
 304                 return 0;
 305
 306         /* Get the dma-ranges from DT */
 307         for_each_of_pci_range(&parser, &range) {
 308                 /* Hardware only allows one inbound 32-bit range */
 309                 if (index)
 310                         return -EINVAL;
 311
 312                 pci->window_addr = (unsigned long)range.cpu_addr;
 313                 pci->window_pci = (unsigned long)range.pci_addr;
 314                 pci->window_size = (unsigned long)range.size;
 315
 316                 /* Catch HW limitations */
 317                 if (!(range.flags & IORESOURCE_PREFETCH)) {
 318                         dev_err(dev, "window must be prefetchable\n");
 319                         return -EINVAL;
 320                 }
 321                 if (pci->window_addr) {
 322                         u32 lowaddr = 1 << (ffs(pci->window_addr) - 1);
 323
 324                         if (lowaddr < pci->window_size) {
 325                                 dev_err(dev, "invalid window size/addr\n");
 326                                 return -EINVAL;
 327                         }
 328                 }
 329                 index++;
 330         }
 331
 332         return 0;
 333 }
 334
 335 static int rcar_pci_probe(struct platform_device *pdev)
 336 {
 337         struct device *dev = &pdev->dev;
 338         struct resource *cfg_res, *mem_res;
 339         struct rcar_pci_priv *priv;
 340         void __iomem *reg;
 341         struct hw_pci hw;
 342         void *hw_private[1];
 343
 344         cfg_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 345         reg = devm_ioremap_resource(dev, cfg_res);
 346         if (IS_ERR(reg))
 347                 return PTR_ERR(reg);
 348
 349         mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 350         if (!mem_res || !mem_res->start)
 351                 return -ENODEV;
 352
 353         if (mem_res->start & 0xFFFF)
 354                 return -EINVAL;
 355
 356         priv = devm_kzalloc(dev, sizeof(struct rcar_pci_priv), GFP_KERNEL);
 357         if (!priv)
 358                 return -ENOMEM;
 359
 360         priv->mem_res = *mem_res;
 361         priv->cfg_res = cfg_res;
 362
 363         priv->irq = platform_get_irq(pdev, 0);
 364         priv->reg = reg;
 365         priv->dev = dev;
 366
 367         if (priv->irq < 0) {
 368                 dev_err(dev, "no valid irq found\n");
 369                 return priv->irq;
 370         }
 371
 372         /* default window addr and size if not specified in DT */
 373         priv->window_addr = 0x40000000;
 374         priv->window_pci = 0x40000000;
 375         priv->window_size = SZ_1G;
 376
 377         if (dev->of_node) {
 378                 struct resource busnr;
 379                 int ret;
 380
 381                 ret = of_pci_parse_bus_range(dev->of_node, &busnr);
 382                 if (ret < 0) {
 383                         dev_err(dev, "failed to parse bus-range\n");
 384                         return ret;
 385                 }
 386
 387                 priv->busnr = busnr.start;
 388                 if (busnr.end != busnr.start)
 389                         dev_warn(dev, "only one bus number supported\n");
 390
 391                 ret = rcar_pci_parse_map_dma_ranges(priv, dev->of_node);
 392                 if (ret < 0) {
 393                         dev_err(dev, "failed to parse dma-range\n");
 394                         return ret;
 395                 }
 396         } else {
 397                 priv->busnr = pdev->id;
 398         }
 399
 400         hw_private[0] = priv;
 401         memset(&hw, 0, sizeof(hw));
 402         hw.nr_controllers = ARRAY_SIZE(hw_private);
 403         hw.io_optional = 1;
 404         hw.private_data = hw_private;
 405         hw.map_irq = rcar_pci_map_irq;
 406         hw.ops = &rcar_pci_ops;
 407         hw.setup = rcar_pci_setup;
 408         pci_common_init_dev(dev, &hw);
 409         return 0;
 410 }
 411
 412 static const struct of_device_id rcar_pci_of_match[] = {
 413         { .compatible = "renesas,pci-r8a7790", },
 414         { .compatible = "renesas,pci-r8a7791", },
 415         { .compatible = "renesas,pci-r8a7794", },
 416         { .compatible = "renesas,pci-rcar-gen2", },
 417         { },
 418 };
 419
 420 static struct platform_driver rcar_pci_driver = {
 421         .driver = {
 422                 .name = "pci-rcar-gen2",
 423                 .suppress_bind_attrs = true,
 424                 .of_match_table = rcar_pci_of_match,
 425         },
 426         .probe = rcar_pci_probe,
 427 };
 428 builtin_platform_driver(rcar_pci_driver);