drivers/usb/host/xhci-mem.c

   1 /*
   2  * xHCI host controller driver
   3  *
   4  * Copyright (C) 2008 Intel Corp.
   5  *
   6  * Author: Sarah Sharp
   7  * Some code borrowed from the Linux EHCI driver.
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  15  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16  * for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software Foundation,
  20  * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21  */
  22
  23 #include <linux/usb.h>
  24
  25 #include "xhci.h"
  26
  27 void xhci_mem_cleanup(struct xhci_hcd *xhci)
  28 {
  29         xhci->page_size = 0;
  30         xhci->page_shift = 0;
  31 }
  32
  33 int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
  34 {
  35         unsigned int    val, val2;
  36         u32 page_size;
  37         int i;
  38
  39         page_size = xhci_readl(xhci, &xhci->op_regs->page_size);
  40         xhci_dbg(xhci, "Supported page size register = 0x%x\n", page_size);
  41         for (i = 0; i < 16; i++) {
  42                 if ((0x1 & page_size) != 0)
  43                         break;
  44                 page_size = page_size >> 1;
  45         }
  46         if (i < 16)
  47                 xhci_dbg(xhci, "Supported page size of %iK\n", (1 << (i+12)) / 1024);
  48         else
  49                 xhci_warn(xhci, "WARN: no supported page size\n");
  50         /* Use 4K pages, since that's common and the minimum the HC supports */
  51         xhci->page_shift = 12;
  52         xhci->page_size = 1 << xhci->page_shift;
  53         xhci_dbg(xhci, "HCD page size set to %iK\n", xhci->page_size / 1024);
  54
  55         /*
  56          * Program the Number of Device Slots Enabled field in the CONFIG
  57          * register with the max value of slots the HC can handle.
  58          */
  59         val = HCS_MAX_SLOTS(xhci_readl(xhci, &xhci->cap_regs->hcs_params1));
  60         xhci_dbg(xhci, "// xHC can handle at most %d device slots.\n",
  61                         (unsigned int) val);
  62         val2 = xhci_readl(xhci, &xhci->op_regs->config_reg);
  63         val |= (val2 & ~HCS_SLOTS_MASK);
  64         xhci_dbg(xhci, "// Setting Max device slots reg = 0x%x.\n",
  65                         (unsigned int) val);
  66         xhci_writel(xhci, val, &xhci->op_regs->config_reg);
  67
  68         xhci->ir_set = &xhci->run_regs->ir_set[0];
  69
  70         return 0;
  71 fail:
  72         xhci_warn(xhci, "Couldn't initialize memory\n");
  73         xhci_mem_cleanup(xhci);
  74         return -ENOMEM;
  75 }