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

0001 // SPDX-License-Identifier: GPL-2.0
0002 /* TI K3 CPPI5 descriptors pool API
0003  *
0004  * Copyright (C) 2020 Texas Instruments Incorporated - http://www.ti.com
0005  */
0006
0007 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
0008
0009 #include <linux/device.h>
0010 #include <linux/dma-mapping.h>
0011 #include <linux/err.h>
0012 #include <linux/genalloc.h>
0013 #include <linux/kernel.h>
0014
0015 #include "k3-cppi-desc-pool.h"
0016
0017 struct k3_cppi_desc_pool {
0018     struct device       *dev;
0019     dma_addr_t      dma_addr;
0020     void            *cpumem;    /* dma_alloc map */
0021     size_t          desc_size;
0022     size_t          mem_size;
0023     size_t          num_desc;
0024     struct gen_pool     *gen_pool;
0025 };
0026
0027 void k3_cppi_desc_pool_destroy(struct k3_cppi_desc_pool *pool)
0028 {
0029     if (!pool)
0030         return;
0031
0032     WARN(gen_pool_size(pool->gen_pool) != gen_pool_avail(pool->gen_pool),
0033          "k3_knav_desc_pool size %zu != avail %zu",
0034          gen_pool_size(pool->gen_pool),
0035          gen_pool_avail(pool->gen_pool));
0036     if (pool->cpumem)
0037         dma_free_coherent(pool->dev, pool->mem_size, pool->cpumem,
0038                   pool->dma_addr);
0039
0040     gen_pool_destroy(pool->gen_pool);   /* frees pool->name */
0041 }
0042
0043 struct k3_cppi_desc_pool *
0044 k3_cppi_desc_pool_create_name(struct device *dev, size_t size,
0045                   size_t desc_size,
0046                   const char *name)
0047 {
0048     struct k3_cppi_desc_pool *pool;
0049     const char *pool_name = NULL;
0050     int ret = -ENOMEM;
0051
0052     pool = devm_kzalloc(dev, sizeof(*pool), GFP_KERNEL);
0053     if (!pool)
0054         return ERR_PTR(ret);
0055
0056     pool->dev = dev;
0057     pool->desc_size = roundup_pow_of_two(desc_size);
0058     pool->num_desc  = size;
0059     pool->mem_size  = pool->num_desc * pool->desc_size;
0060
0061     pool_name = kstrdup_const(name ? name : dev_name(pool->dev),
0062                   GFP_KERNEL);
0063     if (!pool_name)
0064         return ERR_PTR(-ENOMEM);
0065
0066     pool->gen_pool = gen_pool_create(ilog2(pool->desc_size), -1);
0067     if (!pool->gen_pool) {
0068         ret = -ENOMEM;
0069         dev_err(pool->dev, "pool create failed %d\n", ret);
0070         kfree_const(pool_name);
0071         goto gen_pool_create_fail;
0072     }
0073
0074     pool->gen_pool->name = pool_name;
0075
0076     pool->cpumem = dma_alloc_coherent(pool->dev, pool->mem_size,
0077                       &pool->dma_addr, GFP_KERNEL);
0078
0079     if (!pool->cpumem)
0080         goto dma_alloc_fail;
0081
0082     ret = gen_pool_add_virt(pool->gen_pool, (unsigned long)pool->cpumem,
0083                 (phys_addr_t)pool->dma_addr, pool->mem_size,
0084                 -1);
0085     if (ret < 0) {
0086         dev_err(pool->dev, "pool add failed %d\n", ret);
0087         goto gen_pool_add_virt_fail;
0088     }
0089
0090     return pool;
0091
0092 gen_pool_add_virt_fail:
0093     dma_free_coherent(pool->dev, pool->mem_size, pool->cpumem,
0094               pool->dma_addr);
0095 dma_alloc_fail:
0096     gen_pool_destroy(pool->gen_pool);   /* frees pool->name */
0097 gen_pool_create_fail:
0098     devm_kfree(pool->dev, pool);
0099     return ERR_PTR(ret);
0100 }
0101
0102 dma_addr_t k3_cppi_desc_pool_virt2dma(struct k3_cppi_desc_pool *pool,
0103                       void *addr)
0104 {
0105     return addr ? pool->dma_addr + (addr - pool->cpumem) : 0;
0106 }
0107
0108 void *k3_cppi_desc_pool_dma2virt(struct k3_cppi_desc_pool *pool, dma_addr_t dma)
0109 {
0110     return dma ? pool->cpumem + (dma - pool->dma_addr) : NULL;
0111 }
0112
0113 void *k3_cppi_desc_pool_alloc(struct k3_cppi_desc_pool *pool)
0114 {
0115     return (void *)gen_pool_alloc(pool->gen_pool, pool->desc_size);
0116 }
0117
0118 void k3_cppi_desc_pool_free(struct k3_cppi_desc_pool *pool, void *addr)
0119 {
0120     gen_pool_free(pool->gen_pool, (unsigned long)addr, pool->desc_size);
0121 }
0122
0123 size_t k3_cppi_desc_pool_avail(struct k3_cppi_desc_pool *pool)
0124 {
0125     return gen_pool_avail(pool->gen_pool) / pool->desc_size;
0126 }