drivers/pci/host/pci-keystone-dw.c

   1 /*
   2  * Designware application register space functions for Keystone PCI controller
   3  *
   4  * Copyright (C) 2013-2014 Texas Instruments., Ltd.
   5  *              http://www.ti.com
   6  *
   7  * Author: Murali Karicheri <m-karicheri2@ti.com>
   8  *
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  */
  14
  15 #include <linux/irq.h>
  16 #include <linux/irqdomain.h>
  17 #include <linux/module.h>
  18 #include <linux/of.h>
  19 #include <linux/of_pci.h>
  20 #include <linux/pci.h>
  21 #include <linux/platform_device.h>
  22
  23 #include "pcie-designware.h"
  24 #include "pci-keystone.h"
  25
  26 /* Application register defines */
  27 #define LTSSM_EN_VAL                    1
  28 #define LTSSM_STATE_MASK                0x1f
  29 #define LTSSM_STATE_L0                  0x11
  30 #define DBI_CS2_EN_VAL                  0x20
  31 #define OB_XLAT_EN_VAL                  2
  32
  33 /* Application registers */
  34 #define CMD_STATUS                      0x004
  35 #define CFG_SETUP                       0x008
  36 #define OB_SIZE                         0x030
  37 #define CFG_PCIM_WIN_SZ_IDX             3
  38 #define CFG_PCIM_WIN_CNT                32
  39 #define SPACE0_REMOTE_CFG_OFFSET        0x1000
  40 #define OB_OFFSET_INDEX(n)              (0x200 + (8 * n))
  41 #define OB_OFFSET_HI(n)                 (0x204 + (8 * n))
  42
  43 /* IRQ register defines */
  44 #define IRQ_EOI                         0x050
  45 #define IRQ_STATUS                      0x184
  46 #define IRQ_ENABLE_SET                  0x188
  47 #define IRQ_ENABLE_CLR                  0x18c
  48
  49 #define MSI_IRQ                         0x054
  50 #define MSI0_IRQ_STATUS                 0x104
  51 #define MSI0_IRQ_ENABLE_SET             0x108
  52 #define MSI0_IRQ_ENABLE_CLR             0x10c
  53 #define IRQ_STATUS                      0x184
  54 #define MSI_IRQ_OFFSET                  4
  55
  56 /* Config space registers */
  57 #define DEBUG0                          0x728
  58
  59 #define to_keystone_pcie(x)     container_of(x, struct keystone_pcie, pp)
  60
  61 static inline struct pcie_port *sys_to_pcie(struct pci_sys_data *sys)
  62 {
  63         return sys->private_data;
  64 }
  65
  66 static inline void update_reg_offset_bit_pos(u32 offset, u32 *reg_offset,
  67                                              u32 *bit_pos)
  68 {
  69         *reg_offset = offset % 8;
  70         *bit_pos = offset >> 3;
  71 }
  72
  73 u32 ks_dw_pcie_get_msi_addr(struct pcie_port *pp)
  74 {
  75         struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
  76
  77         return ks_pcie->app.start + MSI_IRQ;
  78 }
  79
  80 void ks_dw_pcie_handle_msi_irq(struct keystone_pcie *ks_pcie, int offset)
  81 {
  82         struct pcie_port *pp = &ks_pcie->pp;
  83         u32 pending, vector;
  84         int src, virq;
  85
  86         pending = readl(ks_pcie->va_app_base + MSI0_IRQ_STATUS + (offset << 4));
  87
  88         /*
  89          * MSI0 status bit 0-3 shows vectors 0, 8, 16, 24, MSI1 status bit
  90          * shows 1, 9, 17, 25 and so forth
  91          */
  92         for (src = 0; src < 4; src++) {
  93                 if (BIT(src) & pending) {
  94                         vector = offset + (src << 3);
  95                         virq = irq_linear_revmap(pp->irq_domain, vector);
  96                         dev_dbg(pp->dev, "irq: bit %d, vector %d, virq %d\n",
  97                                 src, vector, virq);
  98                         generic_handle_irq(virq);
  99                 }
 100         }
 101 }
 102
 103 static void ks_dw_pcie_msi_irq_ack(struct irq_data *d)
 104 {
 105         u32 offset, reg_offset, bit_pos;
 106         struct keystone_pcie *ks_pcie;
 107         unsigned int irq = d->irq;
 108         struct msi_desc *msi;
 109         struct pcie_port *pp;
 110
 111         msi = irq_get_msi_desc(irq);
 112         pp = sys_to_pcie(msi->dev->bus->sysdata);
 113         ks_pcie = to_keystone_pcie(pp);
 114         offset = irq - irq_linear_revmap(pp->irq_domain, 0);
 115         update_reg_offset_bit_pos(offset, &reg_offset, &bit_pos);
 116
 117         writel(BIT(bit_pos),
 118                ks_pcie->va_app_base + MSI0_IRQ_STATUS + (reg_offset << 4));
 119         writel(reg_offset + MSI_IRQ_OFFSET, ks_pcie->va_app_base + IRQ_EOI);
 120 }
 121
 122 void ks_dw_pcie_msi_set_irq(struct pcie_port *pp, int irq)
 123 {
 124         u32 reg_offset, bit_pos;
 125         struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
 126
 127         update_reg_offset_bit_pos(irq, &reg_offset, &bit_pos);
 128         writel(BIT(bit_pos),
 129                ks_pcie->va_app_base + MSI0_IRQ_ENABLE_SET + (reg_offset << 4));
 130 }
 131
 132 void ks_dw_pcie_msi_clear_irq(struct pcie_port *pp, int irq)
 133 {
 134         u32 reg_offset, bit_pos;
 135         struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
 136
 137         update_reg_offset_bit_pos(irq, &reg_offset, &bit_pos);
 138         writel(BIT(bit_pos),
 139                ks_pcie->va_app_base + MSI0_IRQ_ENABLE_CLR + (reg_offset << 4));
 140 }
 141
 142 static void ks_dw_pcie_msi_irq_mask(struct irq_data *d)
 143 {
 144         struct keystone_pcie *ks_pcie;
 145         unsigned int irq = d->irq;
 146         struct msi_desc *msi;
 147         struct pcie_port *pp;
 148         u32 offset;
 149
 150         msi = irq_get_msi_desc(irq);
 151         pp = sys_to_pcie(msi->dev->bus->sysdata);
 152         ks_pcie = to_keystone_pcie(pp);
 153         offset = irq - irq_linear_revmap(pp->irq_domain, 0);
 154
 155         /* Mask the end point if PVM implemented */
 156         if (IS_ENABLED(CONFIG_PCI_MSI)) {
 157                 if (msi->msi_attrib.maskbit)
 158                         pci_msi_mask_irq(d);
 159         }
 160
 161         ks_dw_pcie_msi_clear_irq(pp, offset);
 162 }
 163
 164 static void ks_dw_pcie_msi_irq_unmask(struct irq_data *d)
 165 {
 166         struct keystone_pcie *ks_pcie;
 167         unsigned int irq = d->irq;
 168         struct msi_desc *msi;
 169         struct pcie_port *pp;
 170         u32 offset;
 171
 172         msi = irq_get_msi_desc(irq);
 173         pp = sys_to_pcie(msi->dev->bus->sysdata);
 174         ks_pcie = to_keystone_pcie(pp);
 175         offset = irq - irq_linear_revmap(pp->irq_domain, 0);
 176
 177         /* Mask the end point if PVM implemented */
 178         if (IS_ENABLED(CONFIG_PCI_MSI)) {
 179                 if (msi->msi_attrib.maskbit)
 180                         pci_msi_unmask_irq(d);
 181         }
 182
 183         ks_dw_pcie_msi_set_irq(pp, offset);
 184 }
 185
 186 static struct irq_chip ks_dw_pcie_msi_irq_chip = {
 187         .name = "Keystone-PCIe-MSI-IRQ",
 188         .irq_ack = ks_dw_pcie_msi_irq_ack,
 189         .irq_mask = ks_dw_pcie_msi_irq_mask,
 190         .irq_unmask = ks_dw_pcie_msi_irq_unmask,
 191 };
 192
 193 static int ks_dw_pcie_msi_map(struct irq_domain *domain, unsigned int irq,
 194                               irq_hw_number_t hwirq)
 195 {
 196         irq_set_chip_and_handler(irq, &ks_dw_pcie_msi_irq_chip,
 197                                  handle_level_irq);
 198         irq_set_chip_data(irq, domain->host_data);
 199         set_irq_flags(irq, IRQF_VALID);
 200
 201         return 0;
 202 }
 203
 204 static const struct irq_domain_ops ks_dw_pcie_msi_domain_ops = {
 205         .map = ks_dw_pcie_msi_map,
 206 };
 207
 208 int ks_dw_pcie_msi_host_init(struct pcie_port *pp, struct msi_controller *chip)
 209 {
 210         struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
 211         int i;
 212
 213         pp->irq_domain = irq_domain_add_linear(ks_pcie->msi_intc_np,
 214                                         MAX_MSI_IRQS,
 215                                         &ks_dw_pcie_msi_domain_ops,
 216                                         chip);
 217         if (!pp->irq_domain) {
 218                 dev_err(pp->dev, "irq domain init failed\n");
 219                 return -ENXIO;
 220         }
 221
 222         for (i = 0; i < MAX_MSI_IRQS; i++)
 223                 irq_create_mapping(pp->irq_domain, i);
 224
 225         return 0;
 226 }
 227
 228 void ks_dw_pcie_enable_legacy_irqs(struct keystone_pcie *ks_pcie)
 229 {
 230         int i;
 231
 232         for (i = 0; i < MAX_LEGACY_IRQS; i++)
 233                 writel(0x1, ks_pcie->va_app_base + IRQ_ENABLE_SET + (i << 4));
 234 }
 235
 236 void ks_dw_pcie_handle_legacy_irq(struct keystone_pcie *ks_pcie, int offset)
 237 {
 238         struct pcie_port *pp = &ks_pcie->pp;
 239         u32 pending;
 240         int virq;
 241
 242         pending = readl(ks_pcie->va_app_base + IRQ_STATUS + (offset << 4));
 243
 244         if (BIT(0) & pending) {
 245                 virq = irq_linear_revmap(ks_pcie->legacy_irq_domain, offset);
 246                 dev_dbg(pp->dev, ": irq: irq_offset %d, virq %d\n", offset,
 247                         virq);
 248                 generic_handle_irq(virq);
 249         }
 250
 251         /* EOI the INTx interrupt */
 252         writel(offset, ks_pcie->va_app_base + IRQ_EOI);
 253 }
 254
 255 static void ks_dw_pcie_ack_legacy_irq(struct irq_data *d)
 256 {
 257 }
 258
 259 static void ks_dw_pcie_mask_legacy_irq(struct irq_data *d)
 260 {
 261 }
 262
 263 static void ks_dw_pcie_unmask_legacy_irq(struct irq_data *d)
 264 {
 265 }
 266
 267 static struct irq_chip ks_dw_pcie_legacy_irq_chip = {
 268         .name = "Keystone-PCI-Legacy-IRQ",
 269         .irq_ack = ks_dw_pcie_ack_legacy_irq,
 270         .irq_mask = ks_dw_pcie_mask_legacy_irq,
 271         .irq_unmask = ks_dw_pcie_unmask_legacy_irq,
 272 };
 273
 274 static int ks_dw_pcie_init_legacy_irq_map(struct irq_domain *d,
 275                                 unsigned int irq, irq_hw_number_t hw_irq)
 276 {
 277         irq_set_chip_and_handler(irq, &ks_dw_pcie_legacy_irq_chip,
 278                                  handle_level_irq);
 279         irq_set_chip_data(irq, d->host_data);
 280         set_irq_flags(irq, IRQF_VALID);
 281
 282         return 0;
 283 }
 284
 285 static const struct irq_domain_ops ks_dw_pcie_legacy_irq_domain_ops = {
 286         .map = ks_dw_pcie_init_legacy_irq_map,
 287         .xlate = irq_domain_xlate_onetwocell,
 288 };
 289
 290 /**
 291  * ks_dw_pcie_set_dbi_mode() - Set DBI mode to access overlaid BAR mask
 292  * registers
 293  *
 294  * Since modification of dbi_cs2 involves different clock domain, read the
 295  * status back to ensure the transition is complete.
 296  */
 297 static void ks_dw_pcie_set_dbi_mode(void __iomem *reg_virt)
 298 {
 299         u32 val;
 300
 301         writel(DBI_CS2_EN_VAL | readl(reg_virt + CMD_STATUS),
 302                reg_virt + CMD_STATUS);
 303
 304         do {
 305                 val = readl(reg_virt + CMD_STATUS);
 306         } while (!(val & DBI_CS2_EN_VAL));
 307 }
 308
 309 /**
 310  * ks_dw_pcie_clear_dbi_mode() - Disable DBI mode
 311  *
 312  * Since modification of dbi_cs2 involves different clock domain, read the
 313  * status back to ensure the transition is complete.
 314  */
 315 static void ks_dw_pcie_clear_dbi_mode(void __iomem *reg_virt)
 316 {
 317         u32 val;
 318
 319         writel(~DBI_CS2_EN_VAL & readl(reg_virt + CMD_STATUS),
 320                      reg_virt + CMD_STATUS);
 321
 322         do {
 323                 val = readl(reg_virt + CMD_STATUS);
 324         } while (val & DBI_CS2_EN_VAL);
 325 }
 326
 327 void ks_dw_pcie_setup_rc_app_regs(struct keystone_pcie *ks_pcie)
 328 {
 329         struct pcie_port *pp = &ks_pcie->pp;
 330         u32 start = pp->mem.start, end = pp->mem.end;
 331         int i, tr_size;
 332
 333         /* Disable BARs for inbound access */
 334         ks_dw_pcie_set_dbi_mode(ks_pcie->va_app_base);
 335         writel(0, pp->dbi_base + PCI_BASE_ADDRESS_0);
 336         writel(0, pp->dbi_base + PCI_BASE_ADDRESS_1);
 337         ks_dw_pcie_clear_dbi_mode(ks_pcie->va_app_base);
 338
 339         /* Set outbound translation size per window division */
 340         writel(CFG_PCIM_WIN_SZ_IDX & 0x7, ks_pcie->va_app_base + OB_SIZE);
 341
 342         tr_size = (1 << (CFG_PCIM_WIN_SZ_IDX & 0x7)) * SZ_1M;
 343
 344         /* Using Direct 1:1 mapping of RC <-> PCI memory space */
 345         for (i = 0; (i < CFG_PCIM_WIN_CNT) && (start < end); i++) {
 346                 writel(start | 1, ks_pcie->va_app_base + OB_OFFSET_INDEX(i));
 347                 writel(0, ks_pcie->va_app_base + OB_OFFSET_HI(i));
 348                 start += tr_size;
 349         }
 350
 351         /* Enable OB translation */
 352         writel(OB_XLAT_EN_VAL | readl(ks_pcie->va_app_base + CMD_STATUS),
 353                ks_pcie->va_app_base + CMD_STATUS);
 354 }
 355
 356 /**
 357  * ks_pcie_cfg_setup() - Set up configuration space address for a device
 358  *
 359  * @ks_pcie: ptr to keystone_pcie structure
 360  * @bus: Bus number the device is residing on
 361  * @devfn: device, function number info
 362  *
 363  * Forms and returns the address of configuration space mapped in PCIESS
 364  * address space 0.  Also configures CFG_SETUP for remote configuration space
 365  * access.
 366  *
 367  * The address space has two regions to access configuration - local and remote.
 368  * We access local region for bus 0 (as RC is attached on bus 0) and remote
 369  * region for others with TYPE 1 access when bus > 1.  As for device on bus = 1,
 370  * we will do TYPE 0 access as it will be on our secondary bus (logical).
 371  * CFG_SETUP is needed only for remote configuration access.
 372  */
 373 static void __iomem *ks_pcie_cfg_setup(struct keystone_pcie *ks_pcie, u8 bus,
 374                                        unsigned int devfn)
 375 {
 376         u8 device = PCI_SLOT(devfn), function = PCI_FUNC(devfn);
 377         struct pcie_port *pp = &ks_pcie->pp;
 378         u32 regval;
 379
 380         if (bus == 0)
 381                 return pp->dbi_base;
 382
 383         regval = (bus << 16) | (device << 8) | function;
 384
 385         /*
 386          * Since Bus#1 will be a virtual bus, we need to have TYPE0
 387          * access only.
 388          * TYPE 1
 389          */
 390         if (bus != 1)
 391                 regval |= BIT(24);
 392
 393         writel(regval, ks_pcie->va_app_base + CFG_SETUP);
 394         return pp->va_cfg0_base;
 395 }
 396
 397 int ks_dw_pcie_rd_other_conf(struct pcie_port *pp, struct pci_bus *bus,
 398                              unsigned int devfn, int where, int size, u32 *val)
 399 {
 400         struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
 401         u8 bus_num = bus->number;
 402         void __iomem *addr;
 403
 404         addr = ks_pcie_cfg_setup(ks_pcie, bus_num, devfn);
 405
 406         return dw_pcie_cfg_read(addr + (where & ~0x3), where, size, val);
 407 }
 408
 409 int ks_dw_pcie_wr_other_conf(struct pcie_port *pp, struct pci_bus *bus,
 410                              unsigned int devfn, int where, int size, u32 val)
 411 {
 412         struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
 413         u8 bus_num = bus->number;
 414         void __iomem *addr;
 415
 416         addr = ks_pcie_cfg_setup(ks_pcie, bus_num, devfn);
 417
 418         return dw_pcie_cfg_write(addr + (where & ~0x3), where, size, val);
 419 }
 420
 421 /**
 422  * ks_dw_pcie_v3_65_scan_bus() - keystone scan_bus post initialization
 423  *
 424  * This sets BAR0 to enable inbound access for MSI_IRQ register
 425  */
 426 void ks_dw_pcie_v3_65_scan_bus(struct pcie_port *pp)
 427 {
 428         struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
 429
 430         /* Configure and set up BAR0 */
 431         ks_dw_pcie_set_dbi_mode(ks_pcie->va_app_base);
 432
 433         /* Enable BAR0 */
 434         writel(1, pp->dbi_base + PCI_BASE_ADDRESS_0);
 435         writel(SZ_4K - 1, pp->dbi_base + PCI_BASE_ADDRESS_0);
 436
 437         ks_dw_pcie_clear_dbi_mode(ks_pcie->va_app_base);
 438
 439          /*
 440           * For BAR0, just setting bus address for inbound writes (MSI) should
 441           * be sufficient.  Use physical address to avoid any conflicts.
 442           */
 443         writel(ks_pcie->app.start, pp->dbi_base + PCI_BASE_ADDRESS_0);
 444 }
 445
 446 /**
 447  * ks_dw_pcie_link_up() - Check if link up
 448  */
 449 int ks_dw_pcie_link_up(struct pcie_port *pp)
 450 {
 451         u32 val = readl(pp->dbi_base + DEBUG0);
 452
 453         return (val & LTSSM_STATE_MASK) == LTSSM_STATE_L0;
 454 }
 455
 456 void ks_dw_pcie_initiate_link_train(struct keystone_pcie *ks_pcie)
 457 {
 458         u32 val;
 459
 460         /* Disable Link training */
 461         val = readl(ks_pcie->va_app_base + CMD_STATUS);
 462         val &= ~LTSSM_EN_VAL;
 463         writel(LTSSM_EN_VAL | val,  ks_pcie->va_app_base + CMD_STATUS);
 464
 465         /* Initiate Link Training */
 466         val = readl(ks_pcie->va_app_base + CMD_STATUS);
 467         writel(LTSSM_EN_VAL | val,  ks_pcie->va_app_base + CMD_STATUS);
 468 }
 469
 470 /**
 471  * ks_dw_pcie_host_init() - initialize host for v3_65 dw hardware
 472  *
 473  * Ioremap the register resources, initialize legacy irq domain
 474  * and call dw_pcie_v3_65_host_init() API to initialize the Keystone
 475  * PCI host controller.
 476  */
 477 int __init ks_dw_pcie_host_init(struct keystone_pcie *ks_pcie,
 478                                 struct device_node *msi_intc_np)
 479 {
 480         struct pcie_port *pp = &ks_pcie->pp;
 481         struct platform_device *pdev = to_platform_device(pp->dev);
 482         struct resource *res;
 483
 484         /* Index 0 is the config reg. space address */
 485         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 486         pp->dbi_base = devm_ioremap_resource(pp->dev, res);
 487         if (IS_ERR(pp->dbi_base))
 488                 return PTR_ERR(pp->dbi_base);
 489
 490         /*
 491          * We set these same and is used in pcie rd/wr_other_conf
 492          * functions
 493          */
 494         pp->va_cfg0_base = pp->dbi_base + SPACE0_REMOTE_CFG_OFFSET;
 495         pp->va_cfg1_base = pp->va_cfg0_base;
 496
 497         /* Index 1 is the application reg. space address */
 498         res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 499         ks_pcie->va_app_base = devm_ioremap_resource(pp->dev, res);
 500         if (IS_ERR(ks_pcie->va_app_base))
 501                 return PTR_ERR(ks_pcie->va_app_base);
 502
 503         ks_pcie->app = *res;
 504
 505         /* Create legacy IRQ domain */
 506         ks_pcie->legacy_irq_domain =
 507                         irq_domain_add_linear(ks_pcie->legacy_intc_np,
 508                                         MAX_LEGACY_IRQS,
 509                                         &ks_dw_pcie_legacy_irq_domain_ops,
 510                                         NULL);
 511         if (!ks_pcie->legacy_irq_domain) {
 512                 dev_err(pp->dev, "Failed to add irq domain for legacy irqs\n");
 513                 return -EINVAL;
 514         }
 515
 516         return dw_pcie_host_init(pp);
 517 }