// SPDX-License-Identifier: GPL-2.0
/* TI K3 CPPI5 descriptors pool API
 *
 * Copyright (C) 2020 Texas Instruments Incorporated - http://www.ti.com
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/genalloc.h>
#include <linux/kernel.h>

#include "k3-cppi-desc-pool.h"

struct k3_cppi_desc_pool {
        struct device           *dev;
        dma_addr_t              dma_addr;
        void                    *cpumem;        /* dma_alloc map */
        size_t                  desc_size;
        size_t                  mem_size;
        size_t                  num_desc;
        struct gen_pool         *gen_pool;
        void                    **desc_infos;
};

void k3_cppi_desc_pool_destroy(struct k3_cppi_desc_pool *pool)
{
        if (!pool)
                return;

        WARN(gen_pool_size(pool->gen_pool) != gen_pool_avail(pool->gen_pool),
             "k3_knav_desc_pool size %zu != avail %zu",
             gen_pool_size(pool->gen_pool),
             gen_pool_avail(pool->gen_pool));
        if (pool->cpumem)
                dma_free_coherent(pool->dev, pool->mem_size, pool->cpumem,
                                  pool->dma_addr);

        kfree(pool->desc_infos);

        gen_pool_destroy(pool->gen_pool);       /* frees pool->name */

        kfree(pool);
}
EXPORT_SYMBOL_GPL(k3_cppi_desc_pool_destroy);

struct k3_cppi_desc_pool *
k3_cppi_desc_pool_create_name(struct device *dev, size_t size,
                              size_t desc_size,
                              const char *name)
{
        struct k3_cppi_desc_pool *pool;
        const char *pool_name = NULL;
        int ret = -ENOMEM;

        pool = kzalloc_obj(*pool);
        if (!pool)
                return ERR_PTR(ret);

        pool->dev = dev;
        pool->desc_size = roundup_pow_of_two(desc_size);
        pool->num_desc  = size;
        pool->mem_size  = pool->num_desc * pool->desc_size;

        pool_name = kstrdup_const(name ? name : dev_name(pool->dev),
                                  GFP_KERNEL);
        if (!pool_name)
                goto gen_pool_create_fail;

        pool->gen_pool = gen_pool_create(ilog2(pool->desc_size), -1);
        if (!pool->gen_pool) {
                kfree_const(pool_name);
                goto gen_pool_create_fail;
        }

        pool->gen_pool->name = pool_name;

        pool->desc_infos = kzalloc_objs(*pool->desc_infos, pool->num_desc);
        if (!pool->desc_infos)
                goto gen_pool_desc_infos_alloc_fail;

        pool->cpumem = dma_alloc_coherent(pool->dev, pool->mem_size,
                                          &pool->dma_addr, GFP_KERNEL);

        if (!pool->cpumem)
                goto dma_alloc_fail;

        ret = gen_pool_add_virt(pool->gen_pool, (unsigned long)pool->cpumem,
                                (phys_addr_t)pool->dma_addr, pool->mem_size,
                                -1);
        if (ret < 0) {
                dev_err(pool->dev, "pool add failed %d\n", ret);
                goto gen_pool_add_virt_fail;
        }

        return pool;

gen_pool_add_virt_fail:
        dma_free_coherent(pool->dev, pool->mem_size, pool->cpumem,
                          pool->dma_addr);
dma_alloc_fail:
        kfree(pool->desc_infos);
gen_pool_desc_infos_alloc_fail:
        gen_pool_destroy(pool->gen_pool);       /* frees pool->name */
gen_pool_create_fail:
        kfree(pool);
        return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(k3_cppi_desc_pool_create_name);

dma_addr_t k3_cppi_desc_pool_virt2dma(struct k3_cppi_desc_pool *pool,
                                      void *addr)
{
        return addr ? pool->dma_addr + (addr - pool->cpumem) : 0;
}
EXPORT_SYMBOL_GPL(k3_cppi_desc_pool_virt2dma);

void *k3_cppi_desc_pool_dma2virt(struct k3_cppi_desc_pool *pool, dma_addr_t dma)
{
        return dma ? pool->cpumem + (dma - pool->dma_addr) : NULL;
}
EXPORT_SYMBOL_GPL(k3_cppi_desc_pool_dma2virt);

void *k3_cppi_desc_pool_alloc(struct k3_cppi_desc_pool *pool)
{
        return (void *)gen_pool_alloc(pool->gen_pool, pool->desc_size);
}
EXPORT_SYMBOL_GPL(k3_cppi_desc_pool_alloc);

void k3_cppi_desc_pool_free(struct k3_cppi_desc_pool *pool, void *addr)
{
        gen_pool_free(pool->gen_pool, (unsigned long)addr, pool->desc_size);
}
EXPORT_SYMBOL_GPL(k3_cppi_desc_pool_free);

size_t k3_cppi_desc_pool_avail(struct k3_cppi_desc_pool *pool)
{
        return gen_pool_avail(pool->gen_pool) / pool->desc_size;
}
EXPORT_SYMBOL_GPL(k3_cppi_desc_pool_avail);

size_t k3_cppi_desc_pool_desc_size(const struct k3_cppi_desc_pool *pool)
{
        return pool->desc_size;
}
EXPORT_SYMBOL_GPL(k3_cppi_desc_pool_desc_size);

void *k3_cppi_desc_pool_cpuaddr(const struct k3_cppi_desc_pool *pool)
{
        return pool->cpumem;
}
EXPORT_SYMBOL_GPL(k3_cppi_desc_pool_cpuaddr);

void k3_cppi_desc_pool_desc_info_set(struct k3_cppi_desc_pool *pool,
                                     int desc_idx, void *info)
{
        pool->desc_infos[desc_idx] = info;
}
EXPORT_SYMBOL_GPL(k3_cppi_desc_pool_desc_info_set);

void *k3_cppi_desc_pool_desc_info(const struct k3_cppi_desc_pool *pool,
                                  int desc_idx)
{
        return pool->desc_infos[desc_idx];
}
EXPORT_SYMBOL_GPL(k3_cppi_desc_pool_desc_info);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("TI K3 CPPI5 descriptors pool API");