drivers/usb/host/pci-quirks.c

   1 /*
   2  * This file contains code to reset and initialize USB host controllers.
   3  * Some of it includes work-arounds for PCI hardware and BIOS quirks.
   4  * It may need to run early during booting -- before USB would normally
   5  * initialize -- to ensure that Linux doesn't use any legacy modes.
   6  *
   7  *  Copyright (c) 1999 Martin Mares <mj@ucw.cz>
   8  *  (and others)
   9  */
  10
  11 #include <linux/types.h>
  12 #include <linux/kernel.h>
  13 #include <linux/pci.h>
  14 #include <linux/init.h>
  15 #include <linux/delay.h>
  16 #include <linux/acpi.h>
  17 #include "pci-quirks.h"
  18
  19
  20 #define UHCI_USBLEGSUP          0xc0            /* legacy support */
  21 #define UHCI_USBCMD             0               /* command register */
  22 #define UHCI_USBINTR            4               /* interrupt register */
  23 #define UHCI_USBLEGSUP_RWC      0x8f00          /* the R/WC bits */
  24 #define UHCI_USBLEGSUP_RO       0x5040          /* R/O and reserved bits */
  25 #define UHCI_USBCMD_RUN         0x0001          /* RUN/STOP bit */
  26 #define UHCI_USBCMD_HCRESET     0x0002          /* Host Controller reset */
  27 #define UHCI_USBCMD_EGSM        0x0008          /* Global Suspend Mode */
  28 #define UHCI_USBCMD_CONFIGURE   0x0040          /* Config Flag */
  29 #define UHCI_USBINTR_RESUME     0x0002          /* Resume interrupt enable */
  30
  31 #define OHCI_CONTROL            0x04
  32 #define OHCI_CMDSTATUS          0x08
  33 #define OHCI_INTRSTATUS         0x0c
  34 #define OHCI_INTRENABLE         0x10
  35 #define OHCI_INTRDISABLE        0x14
  36 #define OHCI_OCR                (1 << 3)        /* ownership change request */
  37 #define OHCI_CTRL_RWC           (1 << 9)        /* remote wakeup connected */
  38 #define OHCI_CTRL_IR            (1 << 8)        /* interrupt routing */
  39 #define OHCI_INTR_OC            (1 << 30)       /* ownership change */
  40
  41 #define EHCI_HCC_PARAMS         0x08            /* extended capabilities */
  42 #define EHCI_USBCMD             0               /* command register */
  43 #define EHCI_USBCMD_RUN         (1 << 0)        /* RUN/STOP bit */
  44 #define EHCI_USBSTS             4               /* status register */
  45 #define EHCI_USBSTS_HALTED      (1 << 12)       /* HCHalted bit */
  46 #define EHCI_USBINTR            8               /* interrupt register */
  47 #define EHCI_CONFIGFLAG         0x40            /* configured flag register */
  48 #define EHCI_USBLEGSUP          0               /* legacy support register */
  49 #define EHCI_USBLEGSUP_BIOS     (1 << 16)       /* BIOS semaphore */
  50 #define EHCI_USBLEGSUP_OS       (1 << 24)       /* OS semaphore */
  51 #define EHCI_USBLEGCTLSTS       4               /* legacy control/status */
  52 #define EHCI_USBLEGCTLSTS_SOOE  (1 << 13)       /* SMI on ownership change */
  53
  54
  55 /*
  56  * Make sure the controller is completely inactive, unable to
  57  * generate interrupts or do DMA.
  58  */
  59 void uhci_reset_hc(struct pci_dev *pdev, unsigned long base)
  60 {
  61         /* Turn off PIRQ enable and SMI enable.  (This also turns off the
  62          * BIOS's USB Legacy Support.)  Turn off all the R/WC bits too.
  63          */
  64         pci_write_config_word(pdev, UHCI_USBLEGSUP, UHCI_USBLEGSUP_RWC);
  65
  66         /* Reset the HC - this will force us to get a
  67          * new notification of any already connected
  68          * ports due to the virtual disconnect that it
  69          * implies.
  70          */
  71         outw(UHCI_USBCMD_HCRESET, base + UHCI_USBCMD);
  72         mb();
  73         udelay(5);
  74         if (inw(base + UHCI_USBCMD) & UHCI_USBCMD_HCRESET)
  75                 dev_warn(&pdev->dev, "HCRESET not completed yet!\n");
  76
  77         /* Just to be safe, disable interrupt requests and
  78          * make sure the controller is stopped.
  79          */
  80         outw(0, base + UHCI_USBINTR);
  81         outw(0, base + UHCI_USBCMD);
  82 }
  83 EXPORT_SYMBOL_GPL(uhci_reset_hc);
  84
  85 /*
  86  * Initialize a controller that was newly discovered or has just been
  87  * resumed.  In either case we can't be sure of its previous state.
  88  *
  89  * Returns: 1 if the controller was reset, 0 otherwise.
  90  */
  91 int uhci_check_and_reset_hc(struct pci_dev *pdev, unsigned long base)
  92 {
  93         u16 legsup;
  94         unsigned int cmd, intr;
  95
  96         /*
  97          * When restarting a suspended controller, we expect all the
  98          * settings to be the same as we left them:
  99          *
 100          *      PIRQ and SMI disabled, no R/W bits set in USBLEGSUP;
 101          *      Controller is stopped and configured with EGSM set;
 102          *      No interrupts enabled except possibly Resume Detect.
 103          *
 104          * If any of these conditions are violated we do a complete reset.
 105          */
 106         pci_read_config_word(pdev, UHCI_USBLEGSUP, &legsup);
 107         if (legsup & ~(UHCI_USBLEGSUP_RO | UHCI_USBLEGSUP_RWC)) {
 108                 dev_dbg(&pdev->dev, "%s: legsup = 0x%04x\n",
 109                                 __FUNCTION__, legsup);
 110                 goto reset_needed;
 111         }
 112
 113         cmd = inw(base + UHCI_USBCMD);
 114         if ((cmd & UHCI_USBCMD_RUN) || !(cmd & UHCI_USBCMD_CONFIGURE) ||
 115                         !(cmd & UHCI_USBCMD_EGSM)) {
 116                 dev_dbg(&pdev->dev, "%s: cmd = 0x%04x\n",
 117                                 __FUNCTION__, cmd);
 118                 goto reset_needed;
 119         }
 120
 121         intr = inw(base + UHCI_USBINTR);
 122         if (intr & (~UHCI_USBINTR_RESUME)) {
 123                 dev_dbg(&pdev->dev, "%s: intr = 0x%04x\n",
 124                                 __FUNCTION__, intr);
 125                 goto reset_needed;
 126         }
 127         return 0;
 128
 129 reset_needed:
 130         dev_dbg(&pdev->dev, "Performing full reset\n");
 131         uhci_reset_hc(pdev, base);
 132         return 1;
 133 }
 134 EXPORT_SYMBOL_GPL(uhci_check_and_reset_hc);
 135
 136 static inline int io_type_enabled(struct pci_dev *pdev, unsigned int mask)
 137 {
 138         u16 cmd;
 139         return !pci_read_config_word(pdev, PCI_COMMAND, &cmd) && (cmd & mask);
 140 }
 141
 142 #define pio_enabled(dev) io_type_enabled(dev, PCI_COMMAND_IO)
 143 #define mmio_enabled(dev) io_type_enabled(dev, PCI_COMMAND_MEMORY)
 144
 145 static void __devinit quirk_usb_handoff_uhci(struct pci_dev *pdev)
 146 {
 147         unsigned long base = 0;
 148         int i;
 149
 150         if (!pio_enabled(pdev))
 151                 return;
 152
 153         for (i = 0; i < PCI_ROM_RESOURCE; i++)
 154                 if ((pci_resource_flags(pdev, i) & IORESOURCE_IO)) {
 155                         base = pci_resource_start(pdev, i);
 156                         break;
 157                 }
 158
 159         if (base)
 160                 uhci_check_and_reset_hc(pdev, base);
 161 }
 162
 163 static int __devinit mmio_resource_enabled(struct pci_dev *pdev, int idx)
 164 {
 165         return pci_resource_start(pdev, idx) && mmio_enabled(pdev);
 166 }
 167
 168 static void __devinit quirk_usb_handoff_ohci(struct pci_dev *pdev)
 169 {
 170         void __iomem *base;
 171
 172         if (!mmio_resource_enabled(pdev, 0))
 173                 return;
 174
 175         base = ioremap_nocache(pci_resource_start(pdev, 0),
 176                                      pci_resource_len(pdev, 0));
 177         if (base == NULL) return;
 178
 179 /* On PA-RISC, PDC can leave IR set incorrectly; ignore it there. */
 180 #ifndef __hppa__
 181 {
 182         u32 control = readl(base + OHCI_CONTROL);
 183         if (control & OHCI_CTRL_IR) {
 184                 int wait_time = 500; /* arbitrary; 5 seconds */
 185                 writel(OHCI_INTR_OC, base + OHCI_INTRENABLE);
 186                 writel(OHCI_OCR, base + OHCI_CMDSTATUS);
 187                 while (wait_time > 0 &&
 188                                 readl(base + OHCI_CONTROL) & OHCI_CTRL_IR) {
 189                         wait_time -= 10;
 190                         msleep(10);
 191                 }
 192                 if (wait_time <= 0)
 193                         dev_warn(&pdev->dev, "OHCI: BIOS handoff failed"
 194                                         " (BIOS bug?) %08x\n",
 195                                         readl(base + OHCI_CONTROL));
 196
 197                 /* reset controller, preserving RWC */
 198                 writel(control & OHCI_CTRL_RWC, base + OHCI_CONTROL);
 199         }
 200 }
 201 #endif
 202
 203         /*
 204          * disable interrupts
 205          */
 206         writel(~(u32)0, base + OHCI_INTRDISABLE);
 207         writel(~(u32)0, base + OHCI_INTRSTATUS);
 208
 209         iounmap(base);
 210 }
 211
 212 static void __devinit quirk_usb_disable_ehci(struct pci_dev *pdev)
 213 {
 214         int wait_time, delta;
 215         void __iomem *base, *op_reg_base;
 216         u32     hcc_params, val;
 217         u8      offset, cap_length;
 218         int     count = 256/4;
 219         int     tried_handoff = 0;
 220
 221         if (!mmio_resource_enabled(pdev, 0))
 222                 return;
 223
 224         base = ioremap_nocache(pci_resource_start(pdev, 0),
 225                                 pci_resource_len(pdev, 0));
 226         if (base == NULL) return;
 227
 228         cap_length = readb(base);
 229         op_reg_base = base + cap_length;
 230
 231         /* EHCI 0.96 and later may have "extended capabilities"
 232          * spec section 5.1 explains the bios handoff, e.g. for
 233          * booting from USB disk or using a usb keyboard
 234          */
 235         hcc_params = readl(base + EHCI_HCC_PARAMS);
 236         offset = (hcc_params >> 8) & 0xff;
 237         while (offset && count--) {
 238                 u32             cap;
 239                 int             msec;
 240
 241                 pci_read_config_dword(pdev, offset, &cap);
 242                 switch (cap & 0xff) {
 243                 case 1:                 /* BIOS/SMM/... handoff support */
 244                         if ((cap & EHCI_USBLEGSUP_BIOS)) {
 245                                 dev_dbg(&pdev->dev, "EHCI: BIOS handoff\n");
 246
 247 #if 0
 248 /* aleksey_gorelov@phoenix.com reports that some systems need SMI forced on,
 249  * but that seems dubious in general (the BIOS left it off intentionally)
 250  * and is known to prevent some systems from booting.  so we won't do this
 251  * unless maybe we can determine when we're on a system that needs SMI forced.
 252  */
 253                                 /* BIOS workaround (?): be sure the
 254                                  * pre-Linux code receives the SMI
 255                                  */
 256                                 pci_read_config_dword(pdev,
 257                                                 offset + EHCI_USBLEGCTLSTS,
 258                                                 &val);
 259                                 pci_write_config_dword(pdev,
 260                                                 offset + EHCI_USBLEGCTLSTS,
 261                                                 val | EHCI_USBLEGCTLSTS_SOOE);
 262 #endif
 263
 264                                 /* some systems get upset if this semaphore is
 265                                  * set for any other reason than forcing a BIOS
 266                                  * handoff..
 267                                  */
 268                                 pci_write_config_byte(pdev, offset + 3, 1);
 269                         }
 270
 271                         /* if boot firmware now owns EHCI, spin till
 272                          * it hands it over.
 273                          */
 274                         msec = 5000;
 275                         while ((cap & EHCI_USBLEGSUP_BIOS) && (msec > 0)) {
 276                                 tried_handoff = 1;
 277                                 msleep(10);
 278                                 msec -= 10;
 279                                 pci_read_config_dword(pdev, offset, &cap);
 280                         }
 281
 282                         if (cap & EHCI_USBLEGSUP_BIOS) {
 283                                 /* well, possibly buggy BIOS... try to shut
 284                                  * it down, and hope nothing goes too wrong
 285                                  */
 286                                 dev_warn(&pdev->dev, "EHCI: BIOS handoff failed"
 287                                                 " (BIOS bug?) %08x\n", cap);
 288                                 pci_write_config_byte(pdev, offset + 2, 0);
 289                         }
 290
 291                         /* just in case, always disable EHCI SMIs */
 292                         pci_write_config_dword(pdev,
 293                                         offset + EHCI_USBLEGCTLSTS,
 294                                         0);
 295
 296                         /* If the BIOS ever owned the controller then we
 297                          * can't expect any power sessions to remain intact.
 298                          */
 299                         if (tried_handoff)
 300                                 writel(0, op_reg_base + EHCI_CONFIGFLAG);
 301                         break;
 302                 case 0:                 /* illegal reserved capability */
 303                         cap = 0;
 304                         /* FALLTHROUGH */
 305                 default:
 306                         dev_warn(&pdev->dev, "EHCI: unrecognized capability "
 307                                         "%02x\n", cap & 0xff);
 308                         break;
 309                 }
 310                 offset = (cap >> 8) & 0xff;
 311         }
 312         if (!count)
 313                 dev_printk(KERN_DEBUG, &pdev->dev, "EHCI: capability loop?\n");
 314
 315         /*
 316          * halt EHCI & disable its interrupts in any case
 317          */
 318         val = readl(op_reg_base + EHCI_USBSTS);
 319         if ((val & EHCI_USBSTS_HALTED) == 0) {
 320                 val = readl(op_reg_base + EHCI_USBCMD);
 321                 val &= ~EHCI_USBCMD_RUN;
 322                 writel(val, op_reg_base + EHCI_USBCMD);
 323
 324                 wait_time = 2000;
 325                 delta = 100;
 326                 do {
 327                         writel(0x3f, op_reg_base + EHCI_USBSTS);
 328                         udelay(delta);
 329                         wait_time -= delta;
 330                         val = readl(op_reg_base + EHCI_USBSTS);
 331                         if ((val == ~(u32)0) || (val & EHCI_USBSTS_HALTED)) {
 332                                 break;
 333                         }
 334                 } while (wait_time > 0);
 335         }
 336         writel(0, op_reg_base + EHCI_USBINTR);
 337         writel(0x3f, op_reg_base + EHCI_USBSTS);
 338
 339         iounmap(base);
 340
 341         return;
 342 }
 343
 344
 345
 346 static void __devinit quirk_usb_early_handoff(struct pci_dev *pdev)
 347 {
 348         if (pdev->class == PCI_CLASS_SERIAL_USB_UHCI)
 349                 quirk_usb_handoff_uhci(pdev);
 350         else if (pdev->class == PCI_CLASS_SERIAL_USB_OHCI)
 351                 quirk_usb_handoff_ohci(pdev);
 352         else if (pdev->class == PCI_CLASS_SERIAL_USB_EHCI)
 353                 quirk_usb_disable_ehci(pdev);
 354 }
 355 DECLARE_PCI_FIXUP_FINAL(PCI_ANY_ID, PCI_ANY_ID, quirk_usb_early_handoff);