target/linux/imx6/patches-3.10/0009-of-pci-Provide-support-for-parsing-PCI-DT-ranges-pro.patch

   1 From: Andrew Murray <Andrew.Murray@arm.com>
   2 Subject: [PATCH] of/pci: Provide support for parsing PCI DT ranges property
   3
   4 This patch factors out common implementation patterns to reduce overall kernel
   5 code and provide a means for host bridge drivers to directly obtain struct
   6 resources from the DT's ranges property without relying on architecture specific
   7 DT handling. This will make it easier to write archiecture independent host bridge
   8 drivers and mitigate against further duplication of DT parsing code.
   9
  10 This patch can be used in the following way:
  11
  12         struct of_pci_range_parser parser;
  13         struct of_pci_range range;
  14
  15         if (of_pci_range_parser_init(&parser, np))
  16                 ; //no ranges property
  17
  18         for_each_of_pci_range(&parser, &range) {
  19
  20                 /*
  21                         directly access properties of the address range, e.g.:
  22                         range.pci_space, range.pci_addr, range.cpu_addr,
  23                         range.size, range.flags
  24
  25                         alternatively obtain a struct resource, e.g.:
  26                         struct resource res;
  27                         of_pci_range_to_resource(&range, np, &res);
  28                 */
  29         }
  30
  31 Additionally the implementation takes care of adjacent ranges and merges them
  32 into a single range (as was the case with powerpc and microblaze).
  33
  34 Signed-off-by: Andrew Murray <Andrew.Murray@arm.com>
  35 Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
  36 Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
  37 Reviewed-by: Rob Herring <rob.herring@calxeda.com>
  38 Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
  39 Tested-by: Linus Walleij <linus.walleij@linaro.org>
  40 Tested-by: Jingoo Han <jg1.han@samsung.com>
  41 Acked-by: Grant Likely <grant.likely@secretlab.ca>
  42 Signed-off-by: Jason Cooper <jason@lakedaemon.net>
  43 ---
  44  drivers/of/address.c       | 67 ++++++++++++++++++++++++++++++++++++++++++++++
  45  include/linux/of_address.h | 48 +++++++++++++++++++++++++++++++++
  46  2 files changed, 115 insertions(+)
  47
  48 diff --git a/drivers/of/address.c b/drivers/of/address.c
  49 index 04da786..fdd0636 100644
  50 --- a/drivers/of/address.c
  51 +++ b/drivers/of/address.c
  52 @@ -227,6 +227,73 @@ int of_pci_address_to_resource(struct device_node *dev, int bar,
  53         return __of_address_to_resource(dev, addrp, size, flags, NULL, r);
  54  }
  55  EXPORT_SYMBOL_GPL(of_pci_address_to_resource);
  56 +
  57 +int of_pci_range_parser_init(struct of_pci_range_parser *parser,
  58 +                               struct device_node *node)
  59 +{
  60 +       const int na = 3, ns = 2;
  61 +       int rlen;
  62 +
  63 +       parser->node = node;
  64 +       parser->pna = of_n_addr_cells(node);
  65 +       parser->np = parser->pna + na + ns;
  66 +
  67 +       parser->range = of_get_property(node, "ranges", &rlen);
  68 +       if (parser->range == NULL)
  69 +               return -ENOENT;
  70 +
  71 +       parser->end = parser->range + rlen / sizeof(__be32);
  72 +
  73 +       return 0;
  74 +}
  75 +EXPORT_SYMBOL_GPL(of_pci_range_parser_init);
  76 +
  77 +struct of_pci_range *of_pci_range_parser_one(struct of_pci_range_parser *parser,
  78 +                                               struct of_pci_range *range)
  79 +{
  80 +       const int na = 3, ns = 2;
  81 +
  82 +       if (!range)
  83 +               return NULL;
  84 +
  85 +       if (!parser->range || parser->range + parser->np > parser->end)
  86 +               return NULL;
  87 +
  88 +       range->pci_space = parser->range[0];
  89 +       range->flags = of_bus_pci_get_flags(parser->range);
  90 +       range->pci_addr = of_read_number(parser->range + 1, ns);
  91 +       range->cpu_addr = of_translate_address(parser->node,
  92 +                               parser->range + na);
  93 +       range->size = of_read_number(parser->range + parser->pna + na, ns);
  94 +
  95 +       parser->range += parser->np;
  96 +
  97 +       /* Now consume following elements while they are contiguous */
  98 +       while (parser->range + parser->np <= parser->end) {
  99 +               u32 flags, pci_space;
 100 +               u64 pci_addr, cpu_addr, size;
 101 +
 102 +               pci_space = be32_to_cpup(parser->range);
 103 +               flags = of_bus_pci_get_flags(parser->range);
 104 +               pci_addr = of_read_number(parser->range + 1, ns);
 105 +               cpu_addr = of_translate_address(parser->node,
 106 +                               parser->range + na);
 107 +               size = of_read_number(parser->range + parser->pna + na, ns);
 108 +
 109 +               if (flags != range->flags)
 110 +                       break;
 111 +               if (pci_addr != range->pci_addr + range->size ||
 112 +                   cpu_addr != range->cpu_addr + range->size)
 113 +                       break;
 114 +
 115 +               range->size += size;
 116 +               parser->range += parser->np;
 117 +       }
 118 +
 119 +       return range;
 120 +}
 121 +EXPORT_SYMBOL_GPL(of_pci_range_parser_one);
 122 +
 123  #endif /* CONFIG_PCI */
 124
 125  /*
 126 diff --git a/include/linux/of_address.h b/include/linux/of_address.h
 127 index 0506eb5..4c2e6f2 100644
 128 --- a/include/linux/of_address.h
 129 +++ b/include/linux/of_address.h
 130 @@ -4,6 +4,36 @@
 131  #include <linux/errno.h>
 132  #include <linux/of.h>
 133
 134 +struct of_pci_range_parser {
 135 +       struct device_node *node;
 136 +       const __be32 *range;
 137 +       const __be32 *end;
 138 +       int np;
 139 +       int pna;
 140 +};
 141 +
 142 +struct of_pci_range {
 143 +       u32 pci_space;
 144 +       u64 pci_addr;
 145 +       u64 cpu_addr;
 146 +       u64 size;
 147 +       u32 flags;
 148 +};
 149 +
 150 +#define for_each_of_pci_range(parser, range) \
 151 +       for (; of_pci_range_parser_one(parser, range);)
 152 +
 153 +static inline void of_pci_range_to_resource(struct of_pci_range *range,
 154 +                                           struct device_node *np,
 155 +                                           struct resource *res)
 156 +{
 157 +       res->flags = range->flags;
 158 +       res->start = range->cpu_addr;
 159 +       res->end = range->cpu_addr + range->size - 1;
 160 +       res->parent = res->child = res->sibling = NULL;
 161 +       res->name = np->full_name;
 162 +}
 163 +
 164  #ifdef CONFIG_OF_ADDRESS
 165  extern u64 of_translate_address(struct device_node *np, const __be32 *addr);
 166  extern bool of_can_translate_address(struct device_node *dev);
 167 @@ -27,6 +57,11 @@ static inline unsigned long pci_address_to_pio(phys_addr_t addr) { return -1; }
 168  #define pci_address_to_pio pci_address_to_pio
 169  #endif
 170
 171 +extern int of_pci_range_parser_init(struct of_pci_range_parser *parser,
 172 +                       struct device_node *node);
 173 +extern struct of_pci_range *of_pci_range_parser_one(
 174 +                                       struct of_pci_range_parser *parser,
 175 +                                       struct of_pci_range *range);
 176  #else /* CONFIG_OF_ADDRESS */
 177  #ifndef of_address_to_resource
 178  static inline int of_address_to_resource(struct device_node *dev, int index,
 179 @@ -53,6 +88,19 @@ static inline const __be32 *of_get_address(struct device_node *dev, int index,
 180  {
 181         return NULL;
 182  }
 183 +
 184 +static inline int of_pci_range_parser_init(struct of_pci_range_parser *parser,
 185 +                       struct device_node *node)
 186 +{
 187 +       return -1;
 188 +}
 189 +
 190 +static inline struct of_pci_range *of_pci_range_parser_one(
 191 +                                       struct of_pci_range_parser *parser,
 192 +                                       struct of_pci_range *range)
 193 +{
 194 +       return NULL;
 195 +}
 196  #endif /* CONFIG_OF_ADDRESS */
 197
 198
 199 --
 200 1.8.4
 201