drivers/net/ethernet/ti/k3-cppi-desc-pool.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* TI K3 CPPI5 descriptors pool API
   3  *
   4  * Copyright (C) 2020 Texas Instruments Incorporated - http://www.ti.com
   5  */
   6
   7 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   8
   9 #include <linux/device.h>
  10 #include <linux/dma-mapping.h>
  11 #include <linux/err.h>
  12 #include <linux/genalloc.h>
  13 #include <linux/kernel.h>
  14
  15 #include "k3-cppi-desc-pool.h"
  16
  17 struct k3_cppi_desc_pool {
  18         struct device           *dev;
  19         dma_addr_t              dma_addr;
  20         void                    *cpumem;        /* dma_alloc map */
  21         size_t                  desc_size;
  22         size_t                  mem_size;
  23         size_t                  num_desc;
  24         struct gen_pool         *gen_pool;
  25 };
  26
  27 void k3_cppi_desc_pool_destroy(struct k3_cppi_desc_pool *pool)
  28 {
  29         if (!pool)
  30                 return;
  31
  32         WARN(gen_pool_size(pool->gen_pool) != gen_pool_avail(pool->gen_pool),
  33              "k3_knav_desc_pool size %zu != avail %zu",
  34              gen_pool_size(pool->gen_pool),
  35              gen_pool_avail(pool->gen_pool));
  36         if (pool->cpumem)
  37                 dma_free_coherent(pool->dev, pool->mem_size, pool->cpumem,
  38                                   pool->dma_addr);
  39
  40         gen_pool_destroy(pool->gen_pool);       /* frees pool->name */
  41 }
  42
  43 struct k3_cppi_desc_pool *
  44 k3_cppi_desc_pool_create_name(struct device *dev, size_t size,
  45                               size_t desc_size,
  46                               const char *name)
  47 {
  48         struct k3_cppi_desc_pool *pool;
  49         const char *pool_name = NULL;
  50         int ret = -ENOMEM;
  51
  52         pool = devm_kzalloc(dev, sizeof(*pool), GFP_KERNEL);
  53         if (!pool)
  54                 return ERR_PTR(ret);
  55
  56         pool->dev = dev;
  57         pool->desc_size = roundup_pow_of_two(desc_size);
  58         pool->num_desc  = size;
  59         pool->mem_size  = pool->num_desc * pool->desc_size;
  60
  61         pool_name = kstrdup_const(name ? name : dev_name(pool->dev),
  62                                   GFP_KERNEL);
  63         if (!pool_name)
  64                 return ERR_PTR(-ENOMEM);
  65
  66         pool->gen_pool = gen_pool_create(ilog2(pool->desc_size), -1);
  67         if (!pool->gen_pool) {
  68                 ret = -ENOMEM;
  69                 dev_err(pool->dev, "pool create failed %d\n", ret);
  70                 kfree_const(pool_name);
  71                 goto gen_pool_create_fail;
  72         }
  73
  74         pool->gen_pool->name = pool_name;
  75
  76         pool->cpumem = dma_alloc_coherent(pool->dev, pool->mem_size,
  77                                           &pool->dma_addr, GFP_KERNEL);
  78
  79         if (!pool->cpumem)
  80                 goto dma_alloc_fail;
  81
  82         ret = gen_pool_add_virt(pool->gen_pool, (unsigned long)pool->cpumem,
  83                                 (phys_addr_t)pool->dma_addr, pool->mem_size,
  84                                 -1);
  85         if (ret < 0) {
  86                 dev_err(pool->dev, "pool add failed %d\n", ret);
  87                 goto gen_pool_add_virt_fail;
  88         }
  89
  90         return pool;
  91
  92 gen_pool_add_virt_fail:
  93         dma_free_coherent(pool->dev, pool->mem_size, pool->cpumem,
  94                           pool->dma_addr);
  95 dma_alloc_fail:
  96         gen_pool_destroy(pool->gen_pool);       /* frees pool->name */
  97 gen_pool_create_fail:
  98         devm_kfree(pool->dev, pool);
  99         return ERR_PTR(ret);
 100 }
 101
 102 dma_addr_t k3_cppi_desc_pool_virt2dma(struct k3_cppi_desc_pool *pool,
 103                                       void *addr)
 104 {
 105         return addr ? pool->dma_addr + (addr - pool->cpumem) : 0;
 106 }
 107
 108 void *k3_cppi_desc_pool_dma2virt(struct k3_cppi_desc_pool *pool, dma_addr_t dma)
 109 {
 110         return dma ? pool->cpumem + (dma - pool->dma_addr) : NULL;
 111 }
 112
 113 void *k3_cppi_desc_pool_alloc(struct k3_cppi_desc_pool *pool)
 114 {
 115         return (void *)gen_pool_alloc(pool->gen_pool, pool->desc_size);
 116 }
 117
 118 void k3_cppi_desc_pool_free(struct k3_cppi_desc_pool *pool, void *addr)
 119 {
 120         gen_pool_free(pool->gen_pool, (unsigned long)addr, pool->desc_size);
 121 }
 122
 123 size_t k3_cppi_desc_pool_avail(struct k3_cppi_desc_pool *pool)
 124 {
 125         return gen_pool_avail(pool->gen_pool) / pool->desc_size;
 126 }