/* xhci.c - xHCI dummy driver.  */
/*
 *  GRUB  --  GRand Unified Bootloader
 *  Copyright (C) 2011  Free Software Foundation, Inc.
 *
 *  GRUB is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  GRUB is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <grub/dl.h>
#include <grub/mm.h>
#include <grub/usb.h>
#include <grub/usbtrans.h>
#include <grub/misc.h>
#include <grub/pci.h>
#include <grub/cpu/pci.h>
#include <grub/cpu/io.h>
#include <grub/time.h>
#include <grub/loader.h>
#include <grub/list.h>

GRUB_MOD_LICENSE ("GPLv3+");

/* This module solves only xHCI problem:
 * Machine is cold-booted. - > USB keyboard works in GRUB -> Windows boots ->
 * Windows does warm reboot -> USB keyboard does not work in GRUB.
 * This only happens in the ports marked superspeed on the machine.
 * The problem is that Windows seems to leave the the SS ports in SS mode
 * when rebooting and a BIOS bug(?) on warm boot leads to not setting
 * the SS ports in 2.0 mode.
 */

/* Identification values */
#define GRUB_XHCI_CLASS_CODE 0x0c0330
#define GRUB_XHCI_SBRN_VALUE 0x30

#define GRUB_XHCI_PCI_XUSB2PR    0xD0
#define GRUB_XHCI_PCI_USB3_PSSEN 0xD8

/* PCI iteration function... */
static int
grub_xhci_pci_iter (grub_pci_device_t dev,
  grub_pci_id_t pciid __attribute__ ((unused)),
  void __attribute__ ((unused)) *data)
{
  grub_pci_address_t addr;
  grub_uint32_t class_code;
  grub_uint8_t release;
  
  addr = grub_pci_make_address (dev, GRUB_PCI_REG_CLASS);
  class_code = grub_pci_read (addr) >> 8;

  /* If this is not an XHCI controller, just return.  */
  if (class_code != GRUB_XHCI_CLASS_CODE)
    return 0;

  /* Check Serial Bus Release Number */
  addr = grub_pci_make_address (dev, GRUB_XHCI_PCI_SBRN_REG);
  release = grub_pci_read_byte (addr);
  if (release != GRUB_XHCI_SBRN_VALUE)
    return 0;

  /* Since GRUB does not currently handle xHCI we need
   * to make sure it is disabled and the ports put in 2.0 mode.
   * To be removed when xHCI is properly introduced.
   */
  addr = grub_pci_make_address (dev, GRUB_XHCI_PCI_USB3_PSSEN);
  grub_pci_write_word (addr, 0x0);
  grub_pci_read_word(addr);
  addr = grub_pci_make_address (dev, GRUB_XHCI_PCI_XUSB2PR);
  grub_pci_write_word (addr, 0x0);
  grub_pci_read_word(addr);

  return 0;
}


static int
grub_xhci_iterate (grub_usb_controller_iterate_hook_t hook, void *hook_data)
{
  return 0;
}


static grub_usb_err_t
grub_xhci_setup_transfer (grub_usb_controller_t dev,
  grub_usb_transfer_t transfer)
{
  if (dev && transfer) {}
  
  return GRUB_USB_ERR_NONE;
}


static grub_usb_err_t
grub_xhci_check_transfer (grub_usb_controller_t dev,
			  grub_usb_transfer_t transfer, grub_size_t * actual)
{
  if (dev && transfer && actual) {}

  return GRUB_USB_ERR_NONE;
}


static grub_usb_err_t
grub_xhci_cancel_transfer (grub_usb_controller_t dev,
			   grub_usb_transfer_t transfer)
{
  if (dev && transfer) {}

  return GRUB_USB_ERR_NONE;
}


static int
grub_xhci_hubports (grub_usb_controller_t dev)
{
  if (dev) {}

  return 0;
}


static grub_usb_err_t
grub_xhci_portstatus (grub_usb_controller_t dev,
		      unsigned int port, unsigned int enable)
{
  if (dev && port && enable) {}

  return GRUB_USB_ERR_NONE;
}


static grub_usb_speed_t
grub_xhci_detect_dev (grub_usb_controller_t dev, int port, int *changed)
{
  if (dev &&changed) {}

  return GRUB_USB_SPEED_NONE;
}


static grub_err_t
grub_xhci_fini_hw (int noreturn __attribute__ ((unused)))
{
  return GRUB_USB_ERR_NONE;
}


static grub_err_t
grub_xhci_restore_hw (void)
{
  return GRUB_USB_ERR_NONE;
}


static void
grub_xhci_inithw (void)
{
  grub_pci_iterate (grub_xhci_pci_iter, NULL);
}


static struct grub_usb_controller_dev usb_controller = {
  .name = "xhci",
  .iterate = grub_xhci_iterate,
  .setup_transfer = grub_xhci_setup_transfer,
  .check_transfer = grub_xhci_check_transfer,
  .cancel_transfer = grub_xhci_cancel_transfer,
  .hubports = grub_xhci_hubports,
  .portstatus = grub_xhci_portstatus,
  .detect_dev = grub_xhci_detect_dev,
  .max_bulk_tds = 0
};


GRUB_MOD_INIT (xhci)
{
  grub_xhci_inithw ();
}

GRUB_MOD_FINI (xhci)
{
  grub_xhci_fini_hw (0);
}