drivers/usb/host/xhci-mvebu.c

   1 /*
   2  * Copyright (C) 2014 Marvell
   3  * Author: Gregory CLEMENT <gregory.clement@free-electrons.com>
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License
   7  * version 2 as published by the Free Software Foundation.
   8  */
   9
  10 #include <linux/io.h>
  11 #include <linux/mbus.h>
  12 #include <linux/of.h>
  13 #include <linux/platform_device.h>
  14
  15 #include "xhci-mvebu.h"
  16
  17 #define USB3_MAX_WINDOWS        4
  18 #define USB3_WIN_CTRL(w)        (0x0 + ((w) * 8))
  19 #define USB3_WIN_BASE(w)        (0x4 + ((w) * 8))
  20
  21 static void xhci_mvebu_mbus_config(void __iomem *base,
  22                         const struct mbus_dram_target_info *dram)
  23 {
  24         int win;
  25
  26         /* Clear all existing windows */
  27         for (win = 0; win < USB3_MAX_WINDOWS; win++) {
  28                 writel(0, base + USB3_WIN_CTRL(win));
  29                 writel(0, base + USB3_WIN_BASE(win));
  30         }
  31
  32         /* Program each DRAM CS in a seperate window */
  33         for (win = 0; win < dram->num_cs; win++) {
  34                 const struct mbus_dram_window *cs = dram->cs + win;
  35
  36                 writel(((cs->size - 1) & 0xffff0000) | (cs->mbus_attr << 8) |
  37                        (dram->mbus_dram_target_id << 4) | 1,
  38                        base + USB3_WIN_CTRL(win));
  39
  40                 writel((cs->base & 0xffff0000), base + USB3_WIN_BASE(win));
  41         }
  42 }
  43
  44 int xhci_mvebu_mbus_init_quirk(struct platform_device *pdev)
  45 {
  46         struct resource *res;
  47         void __iomem *base;
  48         const struct mbus_dram_target_info *dram;
  49
  50         res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
  51         if (!res)
  52                 return -ENODEV;
  53
  54         /*
  55          * We don't use devm_ioremap() because this mapping should
  56          * only exists for the duration of this probe function.
  57          */
  58         base = ioremap(res->start, resource_size(res));
  59         if (!base)
  60                 return -ENODEV;
  61
  62         dram = mv_mbus_dram_info();
  63         xhci_mvebu_mbus_config(base, dram);
  64
  65         /*
  66          * This memory area was only needed to configure the MBus
  67          * windows, and is therefore no longer useful.
  68          */
  69         iounmap(base);
  70
  71         return 0;
  72 }