target/linux/brcm47xx/patches-3.2/195-bcma-add-support-for-sprom-not-found-on-the-device.patch

   1 From 332b8f6ca7da3197c631928b6bd1e7fdca87e109 Mon Sep 17 00:00:00 2001
   2 From: Hauke Mehrtens <hauke@hauke-m.de>
   3 Date: Sat, 18 Feb 2012 01:16:35 +0100
   4 Subject: [PATCH 195/202] bcma: add support for sprom not found on the device.
   5
   6 On SoCs the sprom is stored in the nvram in a special partition on the
   7 flash chip. The nvram contains the sprom for the main bus, but
   8 sometimes also for a pci devices using bcma. This patch makes it
   9 possible for the arch code to register a function to fetch the needed
  10 sprom from the nvram and provide it to the bcma code.
  11
  12 Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
  13 ---
  14  drivers/bcma/sprom.c      |   80 ++++++++++++++++++++++++++++++++++++++++----
  15  include/linux/bcma/bcma.h |    6 +++
  16  2 files changed, 78 insertions(+), 8 deletions(-)
  17
  18 --- a/drivers/bcma/sprom.c
  19 +++ b/drivers/bcma/sprom.c
  20 @@ -16,6 +16,49 @@
  21
  22  #define SPOFF(offset)  ((offset) / sizeof(u16))
  23
  24 +static int(*get_fallback_sprom)(struct bcma_bus *dev, struct ssb_sprom *out);
  25 +
  26 +/**
  27 + * ssb_arch_register_fallback_sprom - Registers a method providing a
  28 + * fallback SPROM if no SPROM is found.
  29 + *
  30 + * @sprom_callback: The callback function.
  31 + *
  32 + * With this function the architecture implementation may register a
  33 + * callback handler which fills the SPROM data structure. The fallback is
  34 + * only used for PCI based SSB devices, where no valid SPROM can be found
  35 + * in the shadow registers.
  36 + *
  37 + * This function is useful for weird architectures that have a half-assed
  38 + * SSB device hardwired to their PCI bus.
  39 + *
  40 + * Note that it does only work with PCI attached SSB devices. PCMCIA
  41 + * devices currently don't use this fallback.
  42 + * Architectures must provide the SPROM for native SSB devices anyway, so
  43 + * the fallback also isn't used for native devices.
  44 + *
  45 + * This function is available for architecture code, only. So it is not
  46 + * exported.
  47 + */
  48 +int bcma_arch_register_fallback_sprom(int (*sprom_callback)(struct bcma_bus *bus,
  49 +                                    struct ssb_sprom *out))
  50 +{
  51 +       if (get_fallback_sprom)
  52 +               return -EEXIST;
  53 +       get_fallback_sprom = sprom_callback;
  54 +
  55 +       return 0;
  56 +}
  57 +
  58 +static int bcma_fill_sprom_with_fallback(struct bcma_bus *bus,
  59 +                                        struct ssb_sprom *out)
  60 +{
  61 +       if (!get_fallback_sprom)
  62 +               return -ENOENT;
  63 +
  64 +       return get_fallback_sprom(bus, out);
  65 +}
  66 +
  67  /**************************************************
  68   * R/W ops.
  69   **************************************************/
  70 @@ -205,23 +248,44 @@ static void bcma_sprom_extract_r8(struct
  71                 SSB_SROM8_FEM_ANTSWLUT) >> SSB_SROM8_FEM_ANTSWLUT_SHIFT;
  72  }
  73
  74 +static bool bcma_is_sprom_available(struct bcma_bus *bus)
  75 +{
  76 +       u32 sromctrl;
  77 +
  78 +       if (!(bus->drv_cc.capabilities & BCMA_CC_CAP_SPROM))
  79 +               return false;
  80 +
  81 +       if (bus->drv_cc.core->id.rev >= 32) {
  82 +               sromctrl = bcma_read32(bus->drv_cc.core, BCMA_CC_SROM_CONTROL);
  83 +               if (!(sromctrl & BCMA_CC_SROM_CONTROL_PRESENT))
  84 +                       return false;
  85 +       }
  86 +       return true;
  87 +}
  88 +
  89  int bcma_sprom_get(struct bcma_bus *bus)
  90  {
  91         u16 offset;
  92         u16 *sprom;
  93 -       u32 sromctrl;
  94         int err = 0;
  95
  96         if (!bus->drv_cc.core)
  97                 return -EOPNOTSUPP;
  98
  99 -       if (!(bus->drv_cc.capabilities & BCMA_CC_CAP_SPROM))
 100 -               return -ENOENT;
 101 -
 102 -       if (bus->drv_cc.core->id.rev >= 32) {
 103 -               sromctrl = bcma_read32(bus->drv_cc.core, BCMA_CC_SROM_CONTROL);
 104 -               if (!(sromctrl & BCMA_CC_SROM_CONTROL_PRESENT))
 105 -                       return -ENOENT;
 106 +       if (!bcma_is_sprom_available(bus)) {
 107 +               /*
 108 +                * Maybe there is no SPROM on the device?
 109 +                * Now we ask the arch code if there is some sprom
 110 +                * available for this device in some other storage
 111 +                */
 112 +               err = bcma_fill_sprom_with_fallback(bus, &bus->sprom);
 113 +               if (err) {
 114 +                       pr_warn("Using fallback SPROM failed (err %d)\n", err);
 115 +               } else {
 116 +                       pr_debug("Using SPROM revision %d provided by"
 117 +                                " platform.\n", bus->sprom.revision);
 118 +                       return 0;
 119 +               }
 120         }
 121
 122         sprom = kcalloc(SSB_SPROMSIZE_WORDS_R4, sizeof(u16),
 123 --- a/include/linux/bcma/bcma.h
 124 +++ b/include/linux/bcma/bcma.h
 125 @@ -177,6 +177,12 @@ int __bcma_driver_register(struct bcma_d
 126
 127  extern void bcma_driver_unregister(struct bcma_driver *drv);
 128
 129 +/* Set a fallback SPROM.
 130 + * See kdoc at the function definition for complete documentation. */
 131 +extern int bcma_arch_register_fallback_sprom(
 132 +               int (*sprom_callback)(struct bcma_bus *bus,
 133 +               struct ssb_sprom *out));
 134 +
 135  struct bcma_bus {
 136         /* The MMIO area. */
 137         void __iomem *mmio;