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
 17struct 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
 27void 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
 43struct k3_cppi_desc_pool *
 44k3_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
 92gen_pool_add_virt_fail:
 93	dma_free_coherent(pool->dev, pool->mem_size, pool->cpumem,
 94			  pool->dma_addr);
 95dma_alloc_fail:
 96	gen_pool_destroy(pool->gen_pool);	/* frees pool->name */
 97gen_pool_create_fail:
 98	devm_kfree(pool->dev, pool);
 99	return ERR_PTR(ret);
100}
101
102dma_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
108void *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
113void *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
118void 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
123size_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}