drivers/net/ethernet/microchip/sparx5/sparx5_pool.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /* Microchip Sparx5 Switch driver
   3  *
   4  * Copyright (c) 2023 Microchip Technology Inc. and its subsidiaries.
   5  */
   6
   7 #include "sparx5_main_regs.h"
   8 #include "sparx5_main.h"
   9
  10 static u32 sparx5_pool_id_to_idx(u32 id)
  11 {
  12         return --id;
  13 }
  14
  15 u32 sparx5_pool_idx_to_id(u32 idx)
  16 {
  17         return ++idx;
  18 }
  19
  20 /* Release resource from pool.
  21  * Return reference count on success, otherwise return error.
  22  */
  23 int sparx5_pool_put(struct sparx5_pool_entry *pool, int size, u32 id)
  24 {
  25         struct sparx5_pool_entry *e_itr;
  26
  27         e_itr = (pool + sparx5_pool_id_to_idx(id));
  28         if (e_itr->ref_cnt == 0)
  29                 return -EINVAL;
  30
  31         return --e_itr->ref_cnt;
  32 }
  33
  34 /* Get resource from pool.
  35  * Return reference count on success, otherwise return error.
  36  */
  37 int sparx5_pool_get(struct sparx5_pool_entry *pool, int size, u32 *id)
  38 {
  39         struct sparx5_pool_entry *e_itr;
  40         int i;
  41
  42         for (i = 0, e_itr = pool; i < size; i++, e_itr++) {
  43                 if (e_itr->ref_cnt == 0) {
  44                         *id = sparx5_pool_idx_to_id(i);
  45                         return ++e_itr->ref_cnt;
  46                 }
  47         }
  48
  49         return -ENOSPC;
  50 }
  51
  52 /* Get resource from pool that matches index.
  53  * Return reference count on success, otherwise return error.
  54  */
  55 int sparx5_pool_get_with_idx(struct sparx5_pool_entry *pool, int size, u32 idx,
  56                              u32 *id)
  57 {
  58         struct sparx5_pool_entry *e_itr;
  59         int i, ret = -ENOSPC;
  60
  61         for (i = 0, e_itr = pool; i < size; i++, e_itr++) {
  62                 /* Pool index of first free entry */
  63                 if (e_itr->ref_cnt == 0 && ret == -ENOSPC)
  64                         ret = i;
  65                 /* Tc index already in use ? */
  66                 if (e_itr->idx == idx && e_itr->ref_cnt > 0) {
  67                         ret = i;
  68                         break;
  69                 }
  70         }
  71
  72         /* Did we find a free entry? */
  73         if (ret >= 0) {
  74                 *id = sparx5_pool_idx_to_id(ret);
  75                 e_itr = (pool + ret);
  76                 e_itr->idx = idx;
  77                 return ++e_itr->ref_cnt;
  78         }
  79
  80         return ret;
  81 }