src/include/memrange.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 #ifndef MEMRANGE_H_
   3 #define MEMRANGE_H_
   4
   5 #include <device/resource.h>
   6 #include <stdbool.h>
   7 #include <stddef.h>
   8
   9 /* A memranges structure consists of a list of range_entry(s). The structure
  10  * is exposed so that a memranges can be used on the stack if needed. */
  11 struct memranges {
  12         struct range_entry *entries;
  13         /* coreboot doesn't have a free() function. Therefore, keep a cache of
  14          * free'd entries.  */
  15         struct range_entry *free_list;
  16         /* Alignment(log 2) for base and end addresses of the range. */
  17         unsigned char align;
  18 };
  19
  20 /* Each region within a memranges structure is represented by a
  21  * range_entry structure. Use the associated range_entry_(base|end|size|tag)
  22  * functions to interrogate its properties. i.e. don't rely on one's own
  23  * interpretation of the fields. */
  24 struct range_entry {
  25         resource_t begin;
  26         resource_t end;
  27         unsigned long tag;
  28         struct range_entry *next;
  29 };
  30
  31 /* Initialize a range_entry with inclusive beginning address and exclusive
  32  * end address along with the appropriate tag. */
  33 static inline void range_entry_init(struct range_entry *re,
  34                                 resource_t incl_begin, resource_t excl_end,
  35                                 unsigned long tag)
  36 {
  37         re->begin = incl_begin;
  38         re->end = excl_end - 1;
  39         re->tag = tag;
  40         re->next = NULL;
  41 }
  42
  43 /* Return inclusive base address of memory range. */
  44 static inline resource_t range_entry_base(const struct range_entry *r)
  45 {
  46         return r->begin;
  47 }
  48
  49 /* Return exclusive end address of memory range. */
  50 static inline resource_t range_entry_end(const struct range_entry *r)
  51 {
  52         return r->end + 1;
  53 }
  54
  55 /* Return size of memory range. */
  56 static inline resource_t range_entry_size(const struct range_entry *r)
  57 {
  58         return r->end - r->begin + 1;
  59 }
  60
  61 static inline unsigned long range_entry_tag(const struct range_entry *r)
  62 {
  63         return r->tag;
  64 }
  65
  66 static inline void range_entry_update_tag(struct range_entry *r,
  67                                           unsigned long new_tag)
  68 {
  69         r->tag = new_tag;
  70 }
  71
  72 static inline bool memranges_is_empty(const struct memranges *ranges)
  73 {
  74         return ranges->entries == NULL;
  75 }
  76
  77 /* Iterate over each entry in a memranges structure. Ranges cannot
  78  * be deleted while processing each entry as the list cannot be safely
  79  * traversed after such an operation.
  80  * r - range_entry pointer.
  81  * ranges - memranges pointer */
  82 #define memranges_each_entry(r, ranges) \
  83         for (r = (ranges)->entries; r != NULL; r = r->next)
  84
  85 /* Initialize memranges structure providing an optional array of range_entry
  86  * to use as the free list. Additionally, it accepts an align parameter that
  87  * represents the required alignment(log 2) of addresses. */
  88 void memranges_init_empty_with_alignment(struct memranges *ranges,
  89                                          struct range_entry *free,
  90                                          size_t num_free, unsigned char align);
  91
  92 /* Initialize and fill a memranges structure according to the
  93  * mask and match type for all memory resources. Tag each entry with the
  94  * specified type. Additionally, it accepts an align parameter that
  95  * represents the required alignment(log 2) of addresses. */
  96 void memranges_init_with_alignment(struct memranges *ranges,
  97                     unsigned long mask, unsigned long match,
  98                     unsigned long tag, unsigned char align);
  99
 100 /* Initialize memranges structure providing an optional array of range_entry
 101  * to use as the free list. Addresses are default aligned to 4KiB(2^12). */
 102 #define memranges_init_empty(__ranges, __free, __num_free)      \
 103         memranges_init_empty_with_alignment(__ranges, __free, __num_free, 12)
 104
 105 /* Initialize and fill a memranges structure according to the
 106  * mask and match type for all memory resources. Tag each entry with the
 107  * specified type. Addresses are default aligned to 4KiB(2^12). */
 108 #define memranges_init(__ranges, __mask, __match, __tag)        \
 109         memranges_init_with_alignment(__ranges, __mask, __match, __tag, 12)
 110
 111 /* Clone a memrange. The new memrange has the same entries as the old one. */
 112 void memranges_clone(struct memranges *newranges, struct memranges *oldranges);
 113
 114 /* Remove and free all entries within the memranges structure. */
 115 void memranges_teardown(struct memranges *ranges);
 116
 117 /* Add memory resources that match with the corresponding mask and match.
 118  * Each entry will be tagged with the provided tag. e.g.  To populate
 119  * all cacheable memory resources in the range:
 120  * memranges_add_resources(range, IORESOURCE_CACHEABLE,
 121  *                            IORESROUCE_CACHEABLE, my_cacheable_tag); */
 122 void memranges_add_resources(struct memranges *ranges,
 123                              unsigned long mask, unsigned long match,
 124                              unsigned long tag);
 125
 126 /* Add memory resources that match with the corresponding mask and match but
 127  * also provide filter as additional check. The filter will return non-zero
 128  * to add the resource or zero to not add the resource. Each entry will be
 129  * tagged with the provided tag. e.g.  To populate all cacheable memory
 130  * resources in the range with a filter:
 131  * memranges_add_resources_filter(range, IORESOURCE_CACHEABLE,
 132  *                         IORESROUCE_CACHEABLE, my_cacheable_tag, filter); */
 133 typedef int (*memrange_filter_t)(struct device *dev, struct resource *res);
 134 void memranges_add_resources_filter(struct memranges *ranges,
 135                                     unsigned long mask, unsigned long match,
 136                                     unsigned long tag,
 137                                     memrange_filter_t filter);
 138
 139 /* Fill all address ranges up to limit (exclusive) not covered by an entry by
 140  * inserting new entries with the provided tag. */
 141 void memranges_fill_holes_up_to(struct memranges *ranges,
 142                                 resource_t limit, unsigned long tag);
 143
 144 /* Create a hole in the range by deleting/modifying entries that overlap with
 145  * the region specified by base and size. */
 146 void memranges_create_hole(struct memranges *ranges,
 147                            resource_t base, resource_t size);
 148
 149 /* Insert a resource to the given memranges.  All existing ranges
 150  * covered by range specified by base and size will be removed before a
 151  * new one is added. */
 152 void memranges_insert(struct memranges *ranges,
 153                       resource_t base, resource_t size, unsigned long tag);
 154
 155 /* Update all entries with old_tag to new_tag. */
 156 void memranges_update_tag(struct memranges *ranges, unsigned long old_tag,
 157                           unsigned long new_tag);
 158
 159 /* Returns next entry after the provided entry. NULL if r is last. */
 160 struct range_entry *memranges_next_entry(struct memranges *ranges,
 161                                          const struct range_entry *r);
 162
 163 /* Steals memory from the available list in given ranges as per the constraints:
 164  * limit    = Upper bound for the memory range to steal (Inclusive).
 165  * size     = Requested size for the stolen memory.
 166  * align    = Required alignment(log 2) for the starting address of the stolen memory.
 167  * tag      = Use a range that matches the given tag.
 168  * from_top = Steal the highest possible range.
 169  *
 170  * If the constraints can be satisfied, this function creates a hole in the memrange,
 171  * writes the base address of that hole to stolen_base and returns true. Otherwise it returns
 172  * false. */
 173 bool memranges_steal(struct memranges *ranges, resource_t limit, resource_t size,
 174                         unsigned char align, unsigned long tag, resource_t *stolen_base,
 175                         bool from_top);
 176
 177 #endif /* MEMRANGE_H_ */