epca.c: reformat comments and coding style improvements

[linux-2.6/openmoko-kernel.git] / drivers / net / mlx4 / icm.c

/*
 * Copyright (c) 2005 Mellanox Technologies. All rights reserved.
 * Copyright (c) 2006, 2007 Cisco Systems, Inc.  All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include <linux/init.h>
#include <linux/errno.h>
#include <linux/mm.h>
#include <linux/scatterlist.h>

#include <linux/mlx4/cmd.h>

#include "mlx4.h"
#include "icm.h"
#include "fw.h"

/*
 * We allocate in as big chunks as we can, up to a maximum of 256 KB
 * per chunk.
 */
enum {
        MLX4_ICM_ALLOC_SIZE     = 1 << 18,
        MLX4_TABLE_CHUNK_SIZE   = 1 << 18
};

static void mlx4_free_icm_pages(struct mlx4_dev *dev, struct mlx4_icm_chunk *chunk)
{
        int i;

        if (chunk->nsg > 0)
                pci_unmap_sg(dev->pdev, chunk->mem, chunk->npages,
                             PCI_DMA_BIDIRECTIONAL);

        for (i = 0; i < chunk->npages; ++i)
                __free_pages(chunk->mem[i].page,
                             get_order(chunk->mem[i].length));
}

static void mlx4_free_icm_coherent(struct mlx4_dev *dev, struct mlx4_icm_chunk *chunk)
{
        int i;

        for (i = 0; i < chunk->npages; ++i)
                dma_free_coherent(&dev->pdev->dev, chunk->mem[i].length,
                                  lowmem_page_address(chunk->mem[i].page),
                                  sg_dma_address(&chunk->mem[i]));
}

void mlx4_free_icm(struct mlx4_dev *dev, struct mlx4_icm *icm, int coherent)
{
        struct mlx4_icm_chunk *chunk, *tmp;

        if (!icm)
                return;

        list_for_each_entry_safe(chunk, tmp, &icm->chunk_list, list) {
                if (coherent)
                        mlx4_free_icm_coherent(dev, chunk);
                else
                        mlx4_free_icm_pages(dev, chunk);

                kfree(chunk);
        }

        kfree(icm);
}

static int mlx4_alloc_icm_pages(struct scatterlist *mem, int order, gfp_t gfp_mask)
{
        mem->page = alloc_pages(gfp_mask, order);
        if (!mem->page)
                return -ENOMEM;

        mem->length = PAGE_SIZE << order;
        mem->offset = 0;
        return 0;
}

static int mlx4_alloc_icm_coherent(struct device *dev, struct scatterlist *mem,
                                    int order, gfp_t gfp_mask)
{
        void *buf = dma_alloc_coherent(dev, PAGE_SIZE << order,
                                       &sg_dma_address(mem), gfp_mask);
        if (!buf)
                return -ENOMEM;

        sg_set_buf(mem, buf, PAGE_SIZE << order);
        BUG_ON(mem->offset);
        sg_dma_len(mem) = PAGE_SIZE << order;
        return 0;
}

struct mlx4_icm *mlx4_alloc_icm(struct mlx4_dev *dev, int npages,
                                gfp_t gfp_mask, int coherent)
{
        struct mlx4_icm *icm;
        struct mlx4_icm_chunk *chunk = NULL;
        int cur_order;
        int ret;

        /* We use sg_set_buf for coherent allocs, which assumes low memory */
        BUG_ON(coherent && (gfp_mask & __GFP_HIGHMEM));

        icm = kmalloc(sizeof *icm, gfp_mask & ~(__GFP_HIGHMEM | __GFP_NOWARN));
        if (!icm)
                return NULL;

        icm->refcount = 0;
        INIT_LIST_HEAD(&icm->chunk_list);

        cur_order = get_order(MLX4_ICM_ALLOC_SIZE);

        while (npages > 0) {
                if (!chunk) {
                        chunk = kmalloc(sizeof *chunk,
                                        gfp_mask & ~(__GFP_HIGHMEM | __GFP_NOWARN));
                        if (!chunk)
                                goto fail;

                        chunk->npages = 0;
                        chunk->nsg    = 0;
                        list_add_tail(&chunk->list, &icm->chunk_list);
                }

                while (1 << cur_order > npages)
                        --cur_order;

                if (coherent)
                        ret = mlx4_alloc_icm_coherent(&dev->pdev->dev,
                                                      &chunk->mem[chunk->npages],
                                                      cur_order, gfp_mask);
                else
                        ret = mlx4_alloc_icm_pages(&chunk->mem[chunk->npages],
                                                   cur_order, gfp_mask);

                if (!ret) {
                        ++chunk->npages;

                        if (coherent)
                                ++chunk->nsg;
                        else if (chunk->npages == MLX4_ICM_CHUNK_LEN) {
                                chunk->nsg = pci_map_sg(dev->pdev, chunk->mem,
                                                        chunk->npages,
                                                        PCI_DMA_BIDIRECTIONAL);

                                if (chunk->nsg <= 0)
                                        goto fail;

                                chunk = NULL;
                        }

                        npages -= 1 << cur_order;
                } else {
                        --cur_order;
                        if (cur_order < 0)
                                goto fail;
                }
        }

        if (!coherent && chunk) {
                chunk->nsg = pci_map_sg(dev->pdev, chunk->mem,
                                        chunk->npages,
                                        PCI_DMA_BIDIRECTIONAL);

                if (chunk->nsg <= 0)
                        goto fail;
        }

        return icm;

fail:
        mlx4_free_icm(dev, icm, coherent);
        return NULL;
}

static int mlx4_MAP_ICM(struct mlx4_dev *dev, struct mlx4_icm *icm, u64 virt)
{
        return mlx4_map_cmd(dev, MLX4_CMD_MAP_ICM, icm, virt);
}

int mlx4_UNMAP_ICM(struct mlx4_dev *dev, u64 virt, u32 page_count)
{
        return mlx4_cmd(dev, virt, page_count, 0, MLX4_CMD_UNMAP_ICM,
                        MLX4_CMD_TIME_CLASS_B);
}

int mlx4_MAP_ICM_page(struct mlx4_dev *dev, u64 dma_addr, u64 virt)
{
        struct mlx4_cmd_mailbox *mailbox;
        __be64 *inbox;
        int err;

        mailbox = mlx4_alloc_cmd_mailbox(dev);
        if (IS_ERR(mailbox))
                return PTR_ERR(mailbox);
        inbox = mailbox->buf;

        inbox[0] = cpu_to_be64(virt);
        inbox[1] = cpu_to_be64(dma_addr);

        err = mlx4_cmd(dev, mailbox->dma, 1, 0, MLX4_CMD_MAP_ICM,
                       MLX4_CMD_TIME_CLASS_B);

        mlx4_free_cmd_mailbox(dev, mailbox);

        if (!err)
                mlx4_dbg(dev, "Mapped page at %llx to %llx for ICM.\n",
                          (unsigned long long) dma_addr, (unsigned long long) virt);

        return err;
}

int mlx4_MAP_ICM_AUX(struct mlx4_dev *dev, struct mlx4_icm *icm)
{
        return mlx4_map_cmd(dev, MLX4_CMD_MAP_ICM_AUX, icm, -1);
}

int mlx4_UNMAP_ICM_AUX(struct mlx4_dev *dev)
{
        return mlx4_cmd(dev, 0, 0, 0, MLX4_CMD_UNMAP_ICM_AUX, MLX4_CMD_TIME_CLASS_B);
}

int mlx4_table_get(struct mlx4_dev *dev, struct mlx4_icm_table *table, int obj)
{
        int i = (obj & (table->num_obj - 1)) / (MLX4_TABLE_CHUNK_SIZE / table->obj_size);
        int ret = 0;

        mutex_lock(&table->mutex);

        if (table->icm[i]) {
                ++table->icm[i]->refcount;
                goto out;
        }

        table->icm[i] = mlx4_alloc_icm(dev, MLX4_TABLE_CHUNK_SIZE >> PAGE_SHIFT,
                                       (table->lowmem ? GFP_KERNEL : GFP_HIGHUSER) |
                                       __GFP_NOWARN, table->coherent);
        if (!table->icm[i]) {
                ret = -ENOMEM;
                goto out;
        }

        if (mlx4_MAP_ICM(dev, table->icm[i], table->virt +
                         (u64) i * MLX4_TABLE_CHUNK_SIZE)) {
                mlx4_free_icm(dev, table->icm[i], table->coherent);
                table->icm[i] = NULL;
                ret = -ENOMEM;
                goto out;
        }

        ++table->icm[i]->refcount;

out:
        mutex_unlock(&table->mutex);
        return ret;
}

void mlx4_table_put(struct mlx4_dev *dev, struct mlx4_icm_table *table, int obj)
{
        int i;

        i = (obj & (table->num_obj - 1)) / (MLX4_TABLE_CHUNK_SIZE / table->obj_size);

        mutex_lock(&table->mutex);

        if (--table->icm[i]->refcount == 0) {
                mlx4_UNMAP_ICM(dev, table->virt + i * MLX4_TABLE_CHUNK_SIZE,
                               MLX4_TABLE_CHUNK_SIZE / MLX4_ICM_PAGE_SIZE);
                mlx4_free_icm(dev, table->icm[i], table->coherent);
                table->icm[i] = NULL;
        }

        mutex_unlock(&table->mutex);
}

void *mlx4_table_find(struct mlx4_icm_table *table, int obj, dma_addr_t *dma_handle)
{
        int idx, offset, dma_offset, i;
        struct mlx4_icm_chunk *chunk;
        struct mlx4_icm *icm;
        struct page *page = NULL;

        if (!table->lowmem)
                return NULL;

        mutex_lock(&table->mutex);

        idx = (obj & (table->num_obj - 1)) * table->obj_size;
        icm = table->icm[idx / MLX4_TABLE_CHUNK_SIZE];
        dma_offset = offset = idx % MLX4_TABLE_CHUNK_SIZE;

        if (!icm)
                goto out;

        list_for_each_entry(chunk, &icm->chunk_list, list) {
                for (i = 0; i < chunk->npages; ++i) {
                        if (dma_handle && dma_offset >= 0) {
                                if (sg_dma_len(&chunk->mem[i]) > dma_offset)
                                        *dma_handle = sg_dma_address(&chunk->mem[i]) +
                                                dma_offset;
                                dma_offset -= sg_dma_len(&chunk->mem[i]);
                        }
                        /*
                         * DMA mapping can merge pages but not split them,
                         * so if we found the page, dma_handle has already
                         * been assigned to.
                         */
                        if (chunk->mem[i].length > offset) {
                                page = chunk->mem[i].page;
                                goto out;
                        }
                        offset -= chunk->mem[i].length;
                }
        }

out:
        mutex_unlock(&table->mutex);
        return page ? lowmem_page_address(page) + offset : NULL;
}

int mlx4_table_get_range(struct mlx4_dev *dev, struct mlx4_icm_table *table,
                         int start, int end)
{
        int inc = MLX4_TABLE_CHUNK_SIZE / table->obj_size;
        int i, err;

        for (i = start; i <= end; i += inc) {
                err = mlx4_table_get(dev, table, i);
                if (err)
                        goto fail;
        }

        return 0;

fail:
        while (i > start) {
                i -= inc;
                mlx4_table_put(dev, table, i);
        }

        return err;
}

void mlx4_table_put_range(struct mlx4_dev *dev, struct mlx4_icm_table *table,
                          int start, int end)
{
        int i;

        for (i = start; i <= end; i += MLX4_TABLE_CHUNK_SIZE / table->obj_size)
                mlx4_table_put(dev, table, i);
}

int mlx4_init_icm_table(struct mlx4_dev *dev, struct mlx4_icm_table *table,
                        u64 virt, int obj_size, int nobj, int reserved,
                        int use_lowmem, int use_coherent)
{
        int obj_per_chunk;
        int num_icm;
        unsigned chunk_size;
        int i;

        obj_per_chunk = MLX4_TABLE_CHUNK_SIZE / obj_size;
        num_icm = (nobj + obj_per_chunk - 1) / obj_per_chunk;

        table->icm      = kcalloc(num_icm, sizeof *table->icm, GFP_KERNEL);
        if (!table->icm)
                return -ENOMEM;
        table->virt     = virt;
        table->num_icm  = num_icm;
        table->num_obj  = nobj;
        table->obj_size = obj_size;
        table->lowmem   = use_lowmem;
        table->coherent = use_coherent;
        mutex_init(&table->mutex);

        for (i = 0; i * MLX4_TABLE_CHUNK_SIZE < reserved * obj_size; ++i) {
                chunk_size = MLX4_TABLE_CHUNK_SIZE;
                if ((i + 1) * MLX4_TABLE_CHUNK_SIZE > nobj * obj_size)
                        chunk_size = PAGE_ALIGN(nobj * obj_size - i * MLX4_TABLE_CHUNK_SIZE);

                table->icm[i] = mlx4_alloc_icm(dev, chunk_size >> PAGE_SHIFT,
                                               (use_lowmem ? GFP_KERNEL : GFP_HIGHUSER) |
                                               __GFP_NOWARN, use_coherent);
                if (!table->icm[i])
                        goto err;
                if (mlx4_MAP_ICM(dev, table->icm[i], virt + i * MLX4_TABLE_CHUNK_SIZE)) {
                        mlx4_free_icm(dev, table->icm[i], use_coherent);
                        table->icm[i] = NULL;
                        goto err;
                }

                /*
                 * Add a reference to this ICM chunk so that it never
                 * gets freed (since it contains reserved firmware objects).
                 */
                ++table->icm[i]->refcount;
        }

        return 0;

err:
        for (i = 0; i < num_icm; ++i)
                if (table->icm[i]) {
                        mlx4_UNMAP_ICM(dev, virt + i * MLX4_TABLE_CHUNK_SIZE,
                                       MLX4_TABLE_CHUNK_SIZE / MLX4_ICM_PAGE_SIZE);
                        mlx4_free_icm(dev, table->icm[i], use_coherent);
                }

        return -ENOMEM;
}

void mlx4_cleanup_icm_table(struct mlx4_dev *dev, struct mlx4_icm_table *table)
{
        int i;

        for (i = 0; i < table->num_icm; ++i)
                if (table->icm[i]) {
                        mlx4_UNMAP_ICM(dev, table->virt + i * MLX4_TABLE_CHUNK_SIZE,
                                       MLX4_TABLE_CHUNK_SIZE / MLX4_ICM_PAGE_SIZE);
                        mlx4_free_icm(dev, table->icm[i], table->coherent);
                }

        kfree(table->icm);
}