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}
 42EXPORT_SYMBOL_GPL(k3_cppi_desc_pool_destroy);
 43
 44struct k3_cppi_desc_pool *
 45k3_cppi_desc_pool_create_name(struct device *dev, size_t size,
 46			      size_t desc_size,
 47			      const char *name)
 48{
 49	struct k3_cppi_desc_pool *pool;
 50	const char *pool_name = NULL;
 51	int ret = -ENOMEM;
 52
 53	pool = devm_kzalloc(dev, sizeof(*pool), GFP_KERNEL);
 54	if (!pool)
 55		return ERR_PTR(ret);
 56
 57	pool->dev = dev;
 58	pool->desc_size	= roundup_pow_of_two(desc_size);
 59	pool->num_desc	= size;
 60	pool->mem_size	= pool->num_desc * pool->desc_size;
 61
 62	pool_name = kstrdup_const(name ? name : dev_name(pool->dev),
 63				  GFP_KERNEL);
 64	if (!pool_name)
 65		return ERR_PTR(-ENOMEM);
 66
 67	pool->gen_pool = gen_pool_create(ilog2(pool->desc_size), -1);
 68	if (!pool->gen_pool) {
 69		ret = -ENOMEM;
 70		dev_err(pool->dev, "pool create failed %d\n", ret);
 71		kfree_const(pool_name);
 72		goto gen_pool_create_fail;
 73	}
 74
 75	pool->gen_pool->name = pool_name;
 76
 77	pool->cpumem = dma_alloc_coherent(pool->dev, pool->mem_size,
 78					  &pool->dma_addr, GFP_KERNEL);
 79
 80	if (!pool->cpumem)
 81		goto dma_alloc_fail;
 82
 83	ret = gen_pool_add_virt(pool->gen_pool, (unsigned long)pool->cpumem,
 84				(phys_addr_t)pool->dma_addr, pool->mem_size,
 85				-1);
 86	if (ret < 0) {
 87		dev_err(pool->dev, "pool add failed %d\n", ret);
 88		goto gen_pool_add_virt_fail;
 89	}
 90
 91	return pool;
 92
 93gen_pool_add_virt_fail:
 94	dma_free_coherent(pool->dev, pool->mem_size, pool->cpumem,
 95			  pool->dma_addr);
 96dma_alloc_fail:
 97	gen_pool_destroy(pool->gen_pool);	/* frees pool->name */
 98gen_pool_create_fail:
 99	devm_kfree(pool->dev, pool);
100	return ERR_PTR(ret);
101}
102EXPORT_SYMBOL_GPL(k3_cppi_desc_pool_create_name);
103
104dma_addr_t k3_cppi_desc_pool_virt2dma(struct k3_cppi_desc_pool *pool,
105				      void *addr)
106{
107	return addr ? pool->dma_addr + (addr - pool->cpumem) : 0;
108}
109EXPORT_SYMBOL_GPL(k3_cppi_desc_pool_virt2dma);
110
111void *k3_cppi_desc_pool_dma2virt(struct k3_cppi_desc_pool *pool, dma_addr_t dma)
112{
113	return dma ? pool->cpumem + (dma - pool->dma_addr) : NULL;
114}
115EXPORT_SYMBOL_GPL(k3_cppi_desc_pool_dma2virt);
116
117void *k3_cppi_desc_pool_alloc(struct k3_cppi_desc_pool *pool)
118{
119	return (void *)gen_pool_alloc(pool->gen_pool, pool->desc_size);
120}
121EXPORT_SYMBOL_GPL(k3_cppi_desc_pool_alloc);
122
123void k3_cppi_desc_pool_free(struct k3_cppi_desc_pool *pool, void *addr)
124{
125	gen_pool_free(pool->gen_pool, (unsigned long)addr, pool->desc_size);
126}
127EXPORT_SYMBOL_GPL(k3_cppi_desc_pool_free);
128
129size_t k3_cppi_desc_pool_avail(struct k3_cppi_desc_pool *pool)
130{
131	return gen_pool_avail(pool->gen_pool) / pool->desc_size;
132}
133EXPORT_SYMBOL_GPL(k3_cppi_desc_pool_avail);
134
135MODULE_LICENSE("GPL");
136MODULE_DESCRIPTION("TI K3 CPPI5 descriptors pool API");