drivers/pci/host/pcie-spear13xx.c

   1 /*
   2  * PCIe host controller driver for ST Microelectronics SPEAr13xx SoCs
   3  *
   4  * SPEAr13xx PCIe Glue Layer Source Code
   5  *
   6  * Copyright (C) 2010-2014 ST Microelectronics
   7  * Pratyush Anand <pratyush.anand@gmail.com>
   8  * Mohit Kumar <mohit.kumar.dhaka@gmail.com>
   9  *
  10  * This file is licensed under the terms of the GNU General Public
  11  * License version 2. This program is licensed "as is" without any
  12  * warranty of any kind, whether express or implied.
  13  */
  14
  15 #include <linux/clk.h>
  16 #include <linux/delay.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/kernel.h>
  19 #include <linux/module.h>
  20 #include <linux/of.h>
  21 #include <linux/pci.h>
  22 #include <linux/phy/phy.h>
  23 #include <linux/platform_device.h>
  24 #include <linux/resource.h>
  25
  26 #include "pcie-designware.h"
  27
  28 struct spear13xx_pcie {
  29         void __iomem            *app_base;
  30         struct phy              *phy;
  31         struct clk              *clk;
  32         struct pcie_port        pp;
  33         bool                    is_gen1;
  34 };
  35
  36 struct pcie_app_reg {
  37         u32     app_ctrl_0;             /* cr0 */
  38         u32     app_ctrl_1;             /* cr1 */
  39         u32     app_status_0;           /* cr2 */
  40         u32     app_status_1;           /* cr3 */
  41         u32     msg_status;             /* cr4 */
  42         u32     msg_payload;            /* cr5 */
  43         u32     int_sts;                /* cr6 */
  44         u32     int_clr;                /* cr7 */
  45         u32     int_mask;               /* cr8 */
  46         u32     mst_bmisc;              /* cr9 */
  47         u32     phy_ctrl;               /* cr10 */
  48         u32     phy_status;             /* cr11 */
  49         u32     cxpl_debug_info_0;      /* cr12 */
  50         u32     cxpl_debug_info_1;      /* cr13 */
  51         u32     ven_msg_ctrl_0;         /* cr14 */
  52         u32     ven_msg_ctrl_1;         /* cr15 */
  53         u32     ven_msg_data_0;         /* cr16 */
  54         u32     ven_msg_data_1;         /* cr17 */
  55         u32     ven_msi_0;              /* cr18 */
  56         u32     ven_msi_1;              /* cr19 */
  57         u32     mst_rmisc;              /* cr20 */
  58 };
  59
  60 /* CR0 ID */
  61 #define RX_LANE_FLIP_EN_ID                      0
  62 #define TX_LANE_FLIP_EN_ID                      1
  63 #define SYS_AUX_PWR_DET_ID                      2
  64 #define APP_LTSSM_ENABLE_ID                     3
  65 #define SYS_ATTEN_BUTTON_PRESSED_ID             4
  66 #define SYS_MRL_SENSOR_STATE_ID                 5
  67 #define SYS_PWR_FAULT_DET_ID                    6
  68 #define SYS_MRL_SENSOR_CHGED_ID                 7
  69 #define SYS_PRE_DET_CHGED_ID                    8
  70 #define SYS_CMD_CPLED_INT_ID                    9
  71 #define APP_INIT_RST_0_ID                       11
  72 #define APP_REQ_ENTR_L1_ID                      12
  73 #define APP_READY_ENTR_L23_ID                   13
  74 #define APP_REQ_EXIT_L1_ID                      14
  75 #define DEVICE_TYPE_EP                          (0 << 25)
  76 #define DEVICE_TYPE_LEP                         (1 << 25)
  77 #define DEVICE_TYPE_RC                          (4 << 25)
  78 #define SYS_INT_ID                              29
  79 #define MISCTRL_EN_ID                           30
  80 #define REG_TRANSLATION_ENABLE                  31
  81
  82 /* CR1 ID */
  83 #define APPS_PM_XMT_TURNOFF_ID                  2
  84 #define APPS_PM_XMT_PME_ID                      5
  85
  86 /* CR3 ID */
  87 #define XMLH_LTSSM_STATE_DETECT_QUIET           0x00
  88 #define XMLH_LTSSM_STATE_DETECT_ACT             0x01
  89 #define XMLH_LTSSM_STATE_POLL_ACTIVE            0x02
  90 #define XMLH_LTSSM_STATE_POLL_COMPLIANCE        0x03
  91 #define XMLH_LTSSM_STATE_POLL_CONFIG            0x04
  92 #define XMLH_LTSSM_STATE_PRE_DETECT_QUIET       0x05
  93 #define XMLH_LTSSM_STATE_DETECT_WAIT            0x06
  94 #define XMLH_LTSSM_STATE_CFG_LINKWD_START       0x07
  95 #define XMLH_LTSSM_STATE_CFG_LINKWD_ACEPT       0x08
  96 #define XMLH_LTSSM_STATE_CFG_LANENUM_WAIT       0x09
  97 #define XMLH_LTSSM_STATE_CFG_LANENUM_ACEPT      0x0A
  98 #define XMLH_LTSSM_STATE_CFG_COMPLETE           0x0B
  99 #define XMLH_LTSSM_STATE_CFG_IDLE               0x0C
 100 #define XMLH_LTSSM_STATE_RCVRY_LOCK             0x0D
 101 #define XMLH_LTSSM_STATE_RCVRY_SPEED            0x0E
 102 #define XMLH_LTSSM_STATE_RCVRY_RCVRCFG          0x0F
 103 #define XMLH_LTSSM_STATE_RCVRY_IDLE             0x10
 104 #define XMLH_LTSSM_STATE_L0                     0x11
 105 #define XMLH_LTSSM_STATE_L0S                    0x12
 106 #define XMLH_LTSSM_STATE_L123_SEND_EIDLE        0x13
 107 #define XMLH_LTSSM_STATE_L1_IDLE                0x14
 108 #define XMLH_LTSSM_STATE_L2_IDLE                0x15
 109 #define XMLH_LTSSM_STATE_L2_WAKE                0x16
 110 #define XMLH_LTSSM_STATE_DISABLED_ENTRY         0x17
 111 #define XMLH_LTSSM_STATE_DISABLED_IDLE          0x18
 112 #define XMLH_LTSSM_STATE_DISABLED               0x19
 113 #define XMLH_LTSSM_STATE_LPBK_ENTRY             0x1A
 114 #define XMLH_LTSSM_STATE_LPBK_ACTIVE            0x1B
 115 #define XMLH_LTSSM_STATE_LPBK_EXIT              0x1C
 116 #define XMLH_LTSSM_STATE_LPBK_EXIT_TIMEOUT      0x1D
 117 #define XMLH_LTSSM_STATE_HOT_RESET_ENTRY        0x1E
 118 #define XMLH_LTSSM_STATE_HOT_RESET              0x1F
 119 #define XMLH_LTSSM_STATE_MASK                   0x3F
 120 #define XMLH_LINK_UP                            (1 << 6)
 121
 122 /* CR4 ID */
 123 #define CFG_MSI_EN_ID                           18
 124
 125 /* CR6 */
 126 #define INTA_CTRL_INT                           (1 << 7)
 127 #define INTB_CTRL_INT                           (1 << 8)
 128 #define INTC_CTRL_INT                           (1 << 9)
 129 #define INTD_CTRL_INT                           (1 << 10)
 130 #define MSI_CTRL_INT                            (1 << 26)
 131
 132 /* CR19 ID */
 133 #define VEN_MSI_REQ_ID                          11
 134 #define VEN_MSI_FUN_NUM_ID                      8
 135 #define VEN_MSI_TC_ID                           5
 136 #define VEN_MSI_VECTOR_ID                       0
 137 #define VEN_MSI_REQ_EN          ((u32)0x1 << VEN_MSI_REQ_ID)
 138 #define VEN_MSI_FUN_NUM_MASK    ((u32)0x7 << VEN_MSI_FUN_NUM_ID)
 139 #define VEN_MSI_TC_MASK         ((u32)0x7 << VEN_MSI_TC_ID)
 140 #define VEN_MSI_VECTOR_MASK     ((u32)0x1F << VEN_MSI_VECTOR_ID)
 141
 142 #define EXP_CAP_ID_OFFSET                       0x70
 143
 144 #define to_spear13xx_pcie(x)    container_of(x, struct spear13xx_pcie, pp)
 145
 146 static int spear13xx_pcie_establish_link(struct pcie_port *pp)
 147 {
 148         u32 val;
 149         struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pp);
 150         struct pcie_app_reg *app_reg = spear13xx_pcie->app_base;
 151         u32 exp_cap_off = EXP_CAP_ID_OFFSET;
 152         unsigned int retries;
 153
 154         if (dw_pcie_link_up(pp)) {
 155                 dev_err(pp->dev, "link already up\n");
 156                 return 0;
 157         }
 158
 159         dw_pcie_setup_rc(pp);
 160
 161         /*
 162          * this controller support only 128 bytes read size, however its
 163          * default value in capability register is 512 bytes. So force
 164          * it to 128 here.
 165          */
 166         dw_pcie_cfg_read(pp->dbi_base + exp_cap_off + PCI_EXP_DEVCTL, 2, &val);
 167         val &= ~PCI_EXP_DEVCTL_READRQ;
 168         dw_pcie_cfg_write(pp->dbi_base + exp_cap_off + PCI_EXP_DEVCTL, 2, val);
 169
 170         dw_pcie_cfg_write(pp->dbi_base + PCI_VENDOR_ID, 2, 0x104A);
 171         dw_pcie_cfg_write(pp->dbi_base + PCI_DEVICE_ID, 2, 0xCD80);
 172
 173         /*
 174          * if is_gen1 is set then handle it, so that some buggy card
 175          * also works
 176          */
 177         if (spear13xx_pcie->is_gen1) {
 178                 dw_pcie_cfg_read(pp->dbi_base + exp_cap_off + PCI_EXP_LNKCAP,
 179                                         4, &val);
 180                 if ((val & PCI_EXP_LNKCAP_SLS) != PCI_EXP_LNKCAP_SLS_2_5GB) {
 181                         val &= ~((u32)PCI_EXP_LNKCAP_SLS);
 182                         val |= PCI_EXP_LNKCAP_SLS_2_5GB;
 183                         dw_pcie_cfg_write(pp->dbi_base + exp_cap_off +
 184                                 PCI_EXP_LNKCAP, 4, val);
 185                 }
 186
 187                 dw_pcie_cfg_read(pp->dbi_base + exp_cap_off + PCI_EXP_LNKCTL2,
 188                                         2, &val);
 189                 if ((val & PCI_EXP_LNKCAP_SLS) != PCI_EXP_LNKCAP_SLS_2_5GB) {
 190                         val &= ~((u32)PCI_EXP_LNKCAP_SLS);
 191                         val |= PCI_EXP_LNKCAP_SLS_2_5GB;
 192                         dw_pcie_cfg_write(pp->dbi_base + exp_cap_off +
 193                                         PCI_EXP_LNKCTL2, 2, val);
 194                 }
 195         }
 196
 197         /* enable ltssm */
 198         writel(DEVICE_TYPE_RC | (1 << MISCTRL_EN_ID)
 199                         | (1 << APP_LTSSM_ENABLE_ID)
 200                         | ((u32)1 << REG_TRANSLATION_ENABLE),
 201                         &app_reg->app_ctrl_0);
 202
 203         /* check if the link is up or not */
 204         for (retries = 0; retries < 10; retries++) {
 205                 if (dw_pcie_link_up(pp)) {
 206                         dev_info(pp->dev, "link up\n");
 207                         return 0;
 208                 }
 209                 mdelay(100);
 210         }
 211
 212         dev_err(pp->dev, "link Fail\n");
 213         return -EINVAL;
 214 }
 215
 216 static irqreturn_t spear13xx_pcie_irq_handler(int irq, void *arg)
 217 {
 218         struct pcie_port *pp = arg;
 219         struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pp);
 220         struct pcie_app_reg *app_reg = spear13xx_pcie->app_base;
 221         unsigned int status;
 222
 223         status = readl(&app_reg->int_sts);
 224
 225         if (status & MSI_CTRL_INT) {
 226                 BUG_ON(!IS_ENABLED(CONFIG_PCI_MSI));
 227                 dw_handle_msi_irq(pp);
 228         }
 229
 230         writel(status, &app_reg->int_clr);
 231
 232         return IRQ_HANDLED;
 233 }
 234
 235 static void spear13xx_pcie_enable_interrupts(struct pcie_port *pp)
 236 {
 237         struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pp);
 238         struct pcie_app_reg *app_reg = spear13xx_pcie->app_base;
 239
 240         /* Enable MSI interrupt */
 241         if (IS_ENABLED(CONFIG_PCI_MSI)) {
 242                 dw_pcie_msi_init(pp);
 243                 writel(readl(&app_reg->int_mask) |
 244                                 MSI_CTRL_INT, &app_reg->int_mask);
 245         }
 246 }
 247
 248 static int spear13xx_pcie_link_up(struct pcie_port *pp)
 249 {
 250         struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pp);
 251         struct pcie_app_reg *app_reg = spear13xx_pcie->app_base;
 252
 253         if (readl(&app_reg->app_status_1) & XMLH_LINK_UP)
 254                 return 1;
 255
 256         return 0;
 257 }
 258
 259 static void spear13xx_pcie_host_init(struct pcie_port *pp)
 260 {
 261         spear13xx_pcie_establish_link(pp);
 262         spear13xx_pcie_enable_interrupts(pp);
 263 }
 264
 265 static struct pcie_host_ops spear13xx_pcie_host_ops = {
 266         .link_up = spear13xx_pcie_link_up,
 267         .host_init = spear13xx_pcie_host_init,
 268 };
 269
 270 static int spear13xx_add_pcie_port(struct pcie_port *pp,
 271                                          struct platform_device *pdev)
 272 {
 273         struct device *dev = &pdev->dev;
 274         int ret;
 275
 276         pp->irq = platform_get_irq(pdev, 0);
 277         if (!pp->irq) {
 278                 dev_err(dev, "failed to get irq\n");
 279                 return -ENODEV;
 280         }
 281         ret = devm_request_irq(dev, pp->irq, spear13xx_pcie_irq_handler,
 282                                IRQF_SHARED, "spear1340-pcie", pp);
 283         if (ret) {
 284                 dev_err(dev, "failed to request irq %d\n", pp->irq);
 285                 return ret;
 286         }
 287
 288         pp->root_bus_nr = -1;
 289         pp->ops = &spear13xx_pcie_host_ops;
 290
 291         ret = dw_pcie_host_init(pp);
 292         if (ret) {
 293                 dev_err(dev, "failed to initialize host\n");
 294                 return ret;
 295         }
 296
 297         return 0;
 298 }
 299
 300 static int spear13xx_pcie_probe(struct platform_device *pdev)
 301 {
 302         struct spear13xx_pcie *spear13xx_pcie;
 303         struct pcie_port *pp;
 304         struct device *dev = &pdev->dev;
 305         struct device_node *np = pdev->dev.of_node;
 306         struct resource *dbi_base;
 307         int ret;
 308
 309         spear13xx_pcie = devm_kzalloc(dev, sizeof(*spear13xx_pcie), GFP_KERNEL);
 310         if (!spear13xx_pcie)
 311                 return -ENOMEM;
 312
 313         spear13xx_pcie->phy = devm_phy_get(dev, "pcie-phy");
 314         if (IS_ERR(spear13xx_pcie->phy)) {
 315                 ret = PTR_ERR(spear13xx_pcie->phy);
 316                 if (ret == -EPROBE_DEFER)
 317                         dev_info(dev, "probe deferred\n");
 318                 else
 319                         dev_err(dev, "couldn't get pcie-phy\n");
 320                 return ret;
 321         }
 322
 323         phy_init(spear13xx_pcie->phy);
 324
 325         spear13xx_pcie->clk = devm_clk_get(dev, NULL);
 326         if (IS_ERR(spear13xx_pcie->clk)) {
 327                 dev_err(dev, "couldn't get clk for pcie\n");
 328                 return PTR_ERR(spear13xx_pcie->clk);
 329         }
 330         ret = clk_prepare_enable(spear13xx_pcie->clk);
 331         if (ret) {
 332                 dev_err(dev, "couldn't enable clk for pcie\n");
 333                 return ret;
 334         }
 335
 336         pp = &spear13xx_pcie->pp;
 337
 338         pp->dev = dev;
 339
 340         dbi_base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dbi");
 341         pp->dbi_base = devm_ioremap_resource(dev, dbi_base);
 342         if (IS_ERR(pp->dbi_base)) {
 343                 dev_err(dev, "couldn't remap dbi base %p\n", dbi_base);
 344                 ret = PTR_ERR(pp->dbi_base);
 345                 goto fail_clk;
 346         }
 347         spear13xx_pcie->app_base = pp->dbi_base + 0x2000;
 348
 349         if (of_property_read_bool(np, "st,pcie-is-gen1"))
 350                 spear13xx_pcie->is_gen1 = true;
 351
 352         ret = spear13xx_add_pcie_port(pp, pdev);
 353         if (ret < 0)
 354                 goto fail_clk;
 355
 356         platform_set_drvdata(pdev, spear13xx_pcie);
 357         return 0;
 358
 359 fail_clk:
 360         clk_disable_unprepare(spear13xx_pcie->clk);
 361
 362         return ret;
 363 }
 364
 365 static const struct of_device_id spear13xx_pcie_of_match[] = {
 366         { .compatible = "st,spear1340-pcie", },
 367         {},
 368 };
 369 MODULE_DEVICE_TABLE(of, spear13xx_pcie_of_match);
 370
 371 static struct platform_driver spear13xx_pcie_driver = {
 372         .probe          = spear13xx_pcie_probe,
 373         .driver = {
 374                 .name   = "spear-pcie",
 375                 .of_match_table = of_match_ptr(spear13xx_pcie_of_match),
 376         },
 377 };
 378
 379 /* SPEAr13xx PCIe driver does not allow module unload */
 380
 381 static int __init spear13xx_pcie_init(void)
 382 {
 383         return platform_driver_register(&spear13xx_pcie_driver);
 384 }
 385 module_init(spear13xx_pcie_init);
 386
 387 MODULE_DESCRIPTION("ST Microelectronics SPEAr13xx PCIe host controller driver");
 388 MODULE_AUTHOR("Pratyush Anand <pratyush.anand@gmail.com>");
 389 MODULE_LICENSE("GPL v2");