target/linux/mvebu/patches-3.10/0045-bus-mvebu-mbus-Add-static-window-allocation-to-the-D.patch

   1 From ece28a7e105cedb5a9ebd2553aa41d965fb83b64 Mon Sep 17 00:00:00 2001
   2 From: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
   3 Date: Tue, 28 May 2013 07:58:31 -0300
   4 Subject: [PATCH 045/203] bus: mvebu-mbus: Add static window allocation to the
   5  DT binding
   6
   7 This patch adds static window allocation to the device tree binding.
   8 Each first-child of the mbus-compatible node, with a suitable 'ranges'
   9 property, declaring an address translation, will trigger an address
  10 decoding window allocation.
  11
  12 Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
  13 Tested-by: Andrew Lunn <andrew@lunn.ch>
  14 Tested-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
  15 ---
  16  drivers/bus/mvebu-mbus.c | 127 ++++++++++++++++++++++++++++++++++++++++++++++-
  17  1 file changed, 126 insertions(+), 1 deletion(-)
  18
  19 --- a/drivers/bus/mvebu-mbus.c
  20 +++ b/drivers/bus/mvebu-mbus.c
  21 @@ -902,6 +902,127 @@ int __init mvebu_mbus_init(const char *s
  22  }
  23
  24  #ifdef CONFIG_OF
  25 +/*
  26 + * The window IDs in the ranges DT property have the following format:
  27 + *  - bits 28 to 31: MBus custom field
  28 + *  - bits 24 to 27: window target ID
  29 + *  - bits 16 to 23: window attribute ID
  30 + *  - bits  0 to 15: unused
  31 + */
  32 +#define CUSTOM(id) (((id) & 0xF0000000) >> 24)
  33 +#define TARGET(id) (((id) & 0x0F000000) >> 24)
  34 +#define ATTR(id)   (((id) & 0x00FF0000) >> 16)
  35 +
  36 +static int __init mbus_dt_setup_win(struct mvebu_mbus_state *mbus,
  37 +                                   u32 base, u32 size,
  38 +                                   u8 target, u8 attr)
  39 +{
  40 +       const struct mvebu_mbus_mapping *map = mbus->soc->map;
  41 +       const char *name;
  42 +       int i;
  43 +
  44 +       /* Search for a suitable window in the existing mappings */
  45 +       for (i = 0; map[i].name; i++)
  46 +               if (map[i].target == target &&
  47 +                   map[i].attr == (attr & map[i].attrmask))
  48 +                       break;
  49 +
  50 +       name = map[i].name;
  51 +       if (!name) {
  52 +               pr_err("window 0x%x:0x%x is unknown, skipping\n",
  53 +                      target, attr);
  54 +               return -EINVAL;
  55 +       }
  56 +
  57 +       if (!mvebu_mbus_window_conflicts(mbus, base, size, target, attr)) {
  58 +               pr_err("cannot add window '%s', conflicts with another window\n",
  59 +                      name);
  60 +               return -EBUSY;
  61 +       }
  62 +
  63 +       if (mvebu_mbus_alloc_window(mbus, base, size, MVEBU_MBUS_NO_REMAP,
  64 +                                   target, attr)) {
  65 +               pr_err("cannot add window '%s', too many windows\n",
  66 +                      name);
  67 +               return -ENOMEM;
  68 +       }
  69 +       return 0;
  70 +}
  71 +
  72 +static int __init
  73 +mbus_parse_ranges(struct device_node *node,
  74 +                 int *addr_cells, int *c_addr_cells, int *c_size_cells,
  75 +                 int *cell_count, const __be32 **ranges_start,
  76 +                 const __be32 **ranges_end)
  77 +{
  78 +       const __be32 *prop;
  79 +       int ranges_len, tuple_len;
  80 +
  81 +       /* Allow a node with no 'ranges' property */
  82 +       *ranges_start = of_get_property(node, "ranges", &ranges_len);
  83 +       if (*ranges_start == NULL) {
  84 +               *addr_cells = *c_addr_cells = *c_size_cells = *cell_count = 0;
  85 +               *ranges_start = *ranges_end = NULL;
  86 +               return 0;
  87 +       }
  88 +       *ranges_end = *ranges_start + ranges_len / sizeof(__be32);
  89 +
  90 +       *addr_cells = of_n_addr_cells(node);
  91 +
  92 +       prop = of_get_property(node, "#address-cells", NULL);
  93 +       *c_addr_cells = be32_to_cpup(prop);
  94 +
  95 +       prop = of_get_property(node, "#size-cells", NULL);
  96 +       *c_size_cells = be32_to_cpup(prop);
  97 +
  98 +       *cell_count = *addr_cells + *c_addr_cells + *c_size_cells;
  99 +       tuple_len = (*cell_count) * sizeof(__be32);
 100 +
 101 +       if (ranges_len % tuple_len) {
 102 +               pr_warn("malformed ranges entry '%s'\n", node->name);
 103 +               return -EINVAL;
 104 +       }
 105 +       return 0;
 106 +}
 107 +
 108 +static int __init mbus_dt_setup(struct mvebu_mbus_state *mbus,
 109 +                               struct device_node *np)
 110 +{
 111 +       int addr_cells, c_addr_cells, c_size_cells;
 112 +       int i, ret, cell_count;
 113 +       const __be32 *r, *ranges_start, *ranges_end;
 114 +
 115 +       ret = mbus_parse_ranges(np, &addr_cells, &c_addr_cells,
 116 +                               &c_size_cells, &cell_count,
 117 +                               &ranges_start, &ranges_end);
 118 +       if (ret < 0)
 119 +               return ret;
 120 +
 121 +       for (i = 0, r = ranges_start; r < ranges_end; r += cell_count, i++) {
 122 +               u32 windowid, base, size;
 123 +               u8 target, attr;
 124 +
 125 +               /*
 126 +                * An entry with a non-zero custom field do not
 127 +                * correspond to a static window, so skip it.
 128 +                */
 129 +               windowid = of_read_number(r, 1);
 130 +               if (CUSTOM(windowid))
 131 +                       continue;
 132 +
 133 +               target = TARGET(windowid);
 134 +               attr = ATTR(windowid);
 135 +
 136 +               base = of_read_number(r + c_addr_cells, addr_cells);
 137 +               size = of_read_number(r + c_addr_cells + addr_cells,
 138 +                                     c_size_cells);
 139 +               ret = mbus_dt_setup_win(mbus, base, size, target, attr);
 140 +               if (ret < 0)
 141 +                       return ret;
 142 +       }
 143 +       return 0;
 144 +}
 145 +
 146  int __init mvebu_mbus_dt_init(void)
 147  {
 148         struct resource mbuswins_res, sdramwins_res;
 149 @@ -946,6 +1067,10 @@ int __init mvebu_mbus_dt_init(void)
 150                                      resource_size(&mbuswins_res),
 151                                      sdramwins_res.start,
 152                                      resource_size(&sdramwins_res));
 153 -       return ret;
 154 +       if (ret)
 155 +               return ret;
 156 +
 157 +       /* Setup statically declared windows in the DT */
 158 +       return mbus_dt_setup(&mbus_state, np);
 159  }
 160  #endif