/*
 * Copyright (c) 2004 Topspin Communications.  All rights reserved.
 * Copyright (c) 2005 Mellanox Technologies. 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/slab.h>
#include <linux/errno.h>

#include "mthca_dev.h"
#include "mthca_cmd.h"
#include "mthca_memfree.h"

struct mthca_mtt {
        struct mthca_buddy *buddy;
        int                 order;
        u32                 first_seg;
};

/*
 * Must be packed because mtt_seg is 64 bits but only aligned to 32 bits.
 */
struct mthca_mpt_entry {
        __be32 flags;
        __be32 page_size;
        __be32 key;
        __be32 pd;
        __be64 start;
        __be64 length;
        __be32 lkey;
        __be32 window_count;
        __be32 window_count_limit;
        __be64 mtt_seg;
        __be32 mtt_sz;          /* Arbel only */
        u32    reserved[2];
} __packed;

#define MTHCA_MPT_FLAG_SW_OWNS       (0xfUL << 28)
#define MTHCA_MPT_FLAG_MIO           (1 << 17)
#define MTHCA_MPT_FLAG_BIND_ENABLE   (1 << 15)
#define MTHCA_MPT_FLAG_PHYSICAL      (1 <<  9)
#define MTHCA_MPT_FLAG_REGION        (1 <<  8)

#define MTHCA_MTT_FLAG_PRESENT       1

#define MTHCA_MPT_STATUS_SW 0xF0
#define MTHCA_MPT_STATUS_HW 0x00

#define SINAI_FMR_KEY_INC 0x1000000

/*
 * Buddy allocator for MTT segments (currently not very efficient
 * since it doesn't keep a free list and just searches linearly
 * through the bitmaps)
 */

static u32 mthca_buddy_alloc(struct mthca_buddy *buddy, int order)
{
        int o;
        int m;
        u32 seg;

        spin_lock(&buddy->lock);

        for (o = order; o <= buddy->max_order; ++o)
                if (buddy->num_free[o]) {
                        m = 1 << (buddy->max_order - o);
                        seg = find_first_bit(buddy->bits[o], m);
                        if (seg < m)
                                goto found;
                }

        spin_unlock(&buddy->lock);
        return -1;

 found:
        __clear_bit(seg, buddy->bits[o]);
        --buddy->num_free[o];

        while (o > order) {
                --o;
                seg <<= 1;
                __set_bit(seg ^ 1, buddy->bits[o]);
                ++buddy->num_free[o];
        }

        spin_unlock(&buddy->lock);

        seg <<= order;

        return seg;
}

static void mthca_buddy_free(struct mthca_buddy *buddy, u32 seg, int order)
{
        seg >>= order;

        spin_lock(&buddy->lock);

        while (test_bit(seg ^ 1, buddy->bits[order])) {
                __clear_bit(seg ^ 1, buddy->bits[order]);
                --buddy->num_free[order];
                seg >>= 1;
                ++order;
        }

        __set_bit(seg, buddy->bits[order]);
        ++buddy->num_free[order];

        spin_unlock(&buddy->lock);
}

static int mthca_buddy_init(struct mthca_buddy *buddy, int max_order)
{
        int i;

        buddy->max_order = max_order;
        spin_lock_init(&buddy->lock);

        buddy->bits = kcalloc(buddy->max_order + 1, sizeof(*buddy->bits),
                              GFP_KERNEL);
        buddy->num_free = kzalloc_objs(*buddy->num_free, (buddy->max_order + 1));
        if (!buddy->bits || !buddy->num_free)
                goto err_out;

        for (i = 0; i <= buddy->max_order; ++i) {
                buddy->bits[i] = bitmap_zalloc(1 << (buddy->max_order - i),
                                               GFP_KERNEL);
                if (!buddy->bits[i])
                        goto err_out_free;
        }

        __set_bit(0, buddy->bits[buddy->max_order]);
        buddy->num_free[buddy->max_order] = 1;

        return 0;

err_out_free:
        for (i = 0; i <= buddy->max_order; ++i)
                bitmap_free(buddy->bits[i]);

err_out:
        kfree(buddy->bits);
        kfree(buddy->num_free);

        return -ENOMEM;
}

static void mthca_buddy_cleanup(struct mthca_buddy *buddy)
{
        int i;

        for (i = 0; i <= buddy->max_order; ++i)
                bitmap_free(buddy->bits[i]);

        kfree(buddy->bits);
        kfree(buddy->num_free);
}

static u32 mthca_alloc_mtt_range(struct mthca_dev *dev, int order,
                                 struct mthca_buddy *buddy)
{
        u32 seg = mthca_buddy_alloc(buddy, order);

        if (seg == -1)
                return -1;

        if (mthca_is_memfree(dev))
                if (mthca_table_get_range(dev, dev->mr_table.mtt_table, seg,
                                          seg + (1 << order) - 1)) {
                        mthca_buddy_free(buddy, seg, order);
                        seg = -1;
                }

        return seg;
}

static struct mthca_mtt *__mthca_alloc_mtt(struct mthca_dev *dev, int size,
                                           struct mthca_buddy *buddy)
{
        struct mthca_mtt *mtt;
        int i;

        if (size <= 0)
                return ERR_PTR(-EINVAL);

        mtt = kmalloc_obj(*mtt);
        if (!mtt)
                return ERR_PTR(-ENOMEM);

        mtt->buddy = buddy;
        mtt->order = 0;
        for (i = dev->limits.mtt_seg_size / 8; i < size; i <<= 1)
                ++mtt->order;

        mtt->first_seg = mthca_alloc_mtt_range(dev, mtt->order, buddy);
        if (mtt->first_seg == -1) {
                kfree(mtt);
                return ERR_PTR(-ENOMEM);
        }

        return mtt;
}

struct mthca_mtt *mthca_alloc_mtt(struct mthca_dev *dev, int size)
{
        return __mthca_alloc_mtt(dev, size, &dev->mr_table.mtt_buddy);
}

void mthca_free_mtt(struct mthca_dev *dev, struct mthca_mtt *mtt)
{
        if (!mtt)
                return;

        mthca_buddy_free(mtt->buddy, mtt->first_seg, mtt->order);

        mthca_table_put_range(dev, dev->mr_table.mtt_table,
                              mtt->first_seg,
                              mtt->first_seg + (1 << mtt->order) - 1);

        kfree(mtt);
}

static int __mthca_write_mtt(struct mthca_dev *dev, struct mthca_mtt *mtt,
                             int start_index, u64 *buffer_list, int list_len)
{
        struct mthca_mailbox *mailbox;
        __be64 *mtt_entry;
        int err = 0;
        int i;

        mailbox = mthca_alloc_mailbox(dev, GFP_KERNEL);
        if (IS_ERR(mailbox))
                return PTR_ERR(mailbox);
        mtt_entry = mailbox->buf;

        while (list_len > 0) {
                mtt_entry[0] = cpu_to_be64(dev->mr_table.mtt_base +
                                           mtt->first_seg * dev->limits.mtt_seg_size +
                                           start_index * 8);
                mtt_entry[1] = 0;
                for (i = 0; i < list_len && i < MTHCA_MAILBOX_SIZE / 8 - 2; ++i)
                        mtt_entry[i + 2] = cpu_to_be64(buffer_list[i] |
                                                       MTHCA_MTT_FLAG_PRESENT);

                /*
                 * If we have an odd number of entries to write, add
                 * one more dummy entry for firmware efficiency.
                 */
                if (i & 1)
                        mtt_entry[i + 2] = 0;

                err = mthca_WRITE_MTT(dev, mailbox, (i + 1) & ~1);
                if (err) {
                        mthca_warn(dev, "WRITE_MTT failed (%d)\n", err);
                        goto out;
                }

                list_len    -= i;
                start_index += i;
                buffer_list += i;
        }

out:
        mthca_free_mailbox(dev, mailbox);
        return err;
}

int mthca_write_mtt_size(struct mthca_dev *dev)
{
        if (dev->mr_table.fmr_mtt_buddy != &dev->mr_table.mtt_buddy ||
            !(dev->mthca_flags & MTHCA_FLAG_FMR))
                /*
                 * Be friendly to WRITE_MTT command
                 * and leave two empty slots for the
                 * index and reserved fields of the
                 * mailbox.
                 */
                return PAGE_SIZE / sizeof (u64) - 2;

        /* For Arbel, all MTTs must fit in the same page. */
        return mthca_is_memfree(dev) ? (PAGE_SIZE / sizeof (u64)) : 0x7ffffff;
}

static void mthca_tavor_write_mtt_seg(struct mthca_dev *dev,
                                      struct mthca_mtt *mtt, int start_index,
                                      u64 *buffer_list, int list_len)
{
        u64 __iomem *mtts;
        int i;

        mtts = dev->mr_table.tavor_fmr.mtt_base + mtt->first_seg * dev->limits.mtt_seg_size +
                start_index * sizeof (u64);
        for (i = 0; i < list_len; ++i)
                mthca_write64_raw(cpu_to_be64(buffer_list[i] | MTHCA_MTT_FLAG_PRESENT),
                                  mtts + i);
}

static void mthca_arbel_write_mtt_seg(struct mthca_dev *dev,
                                      struct mthca_mtt *mtt, int start_index,
                                      u64 *buffer_list, int list_len)
{
        __be64 *mtts;
        dma_addr_t dma_handle;
        int i;
        int s = start_index * sizeof (u64);

        /* For Arbel, all MTTs must fit in the same page. */
        BUG_ON(s / PAGE_SIZE != (s + list_len * sizeof(u64) - 1) / PAGE_SIZE);
        /* Require full segments */
        BUG_ON(s % dev->limits.mtt_seg_size);

        mtts = mthca_table_find(dev->mr_table.mtt_table, mtt->first_seg +
                                s / dev->limits.mtt_seg_size, &dma_handle);

        BUG_ON(!mtts);

        dma_sync_single_for_cpu(&dev->pdev->dev, dma_handle,
                                list_len * sizeof (u64), DMA_TO_DEVICE);

        for (i = 0; i < list_len; ++i)
                mtts[i] = cpu_to_be64(buffer_list[i] | MTHCA_MTT_FLAG_PRESENT);

        dma_sync_single_for_device(&dev->pdev->dev, dma_handle,
                                   list_len * sizeof (u64), DMA_TO_DEVICE);
}

int mthca_write_mtt(struct mthca_dev *dev, struct mthca_mtt *mtt,
                    int start_index, u64 *buffer_list, int list_len)
{
        int size = mthca_write_mtt_size(dev);
        int chunk;

        if (dev->mr_table.fmr_mtt_buddy != &dev->mr_table.mtt_buddy ||
            !(dev->mthca_flags & MTHCA_FLAG_FMR))
                return __mthca_write_mtt(dev, mtt, start_index, buffer_list, list_len);

        while (list_len > 0) {
                chunk = min(size, list_len);
                if (mthca_is_memfree(dev))
                        mthca_arbel_write_mtt_seg(dev, mtt, start_index,
                                                  buffer_list, chunk);
                else
                        mthca_tavor_write_mtt_seg(dev, mtt, start_index,
                                                  buffer_list, chunk);

                list_len    -= chunk;
                start_index += chunk;
                buffer_list += chunk;
        }

        return 0;
}

static inline u32 tavor_hw_index_to_key(u32 ind)
{
        return ind;
}

static inline u32 tavor_key_to_hw_index(u32 key)
{
        return key;
}

static inline u32 arbel_hw_index_to_key(u32 ind)
{
        return (ind >> 24) | (ind << 8);
}

static inline u32 arbel_key_to_hw_index(u32 key)
{
        return (key << 24) | (key >> 8);
}

static inline u32 hw_index_to_key(struct mthca_dev *dev, u32 ind)
{
        if (mthca_is_memfree(dev))
                return arbel_hw_index_to_key(ind);
        else
                return tavor_hw_index_to_key(ind);
}

static inline u32 key_to_hw_index(struct mthca_dev *dev, u32 key)
{
        if (mthca_is_memfree(dev))
                return arbel_key_to_hw_index(key);
        else
                return tavor_key_to_hw_index(key);
}

static inline u32 adjust_key(struct mthca_dev *dev, u32 key)
{
        if (dev->mthca_flags & MTHCA_FLAG_SINAI_OPT)
                return ((key << 20) & 0x800000) | (key & 0x7fffff);
        else
                return key;
}

int mthca_mr_alloc(struct mthca_dev *dev, u32 pd, int buffer_size_shift,
                   u64 iova, u64 total_size, u32 access, struct mthca_mr *mr)
{
        struct mthca_mailbox *mailbox;
        struct mthca_mpt_entry *mpt_entry;
        u32 key;
        int i;
        int err;

        WARN_ON(buffer_size_shift >= 32);

        key = mthca_alloc(&dev->mr_table.mpt_alloc);
        if (key == -1)
                return -ENOMEM;
        key = adjust_key(dev, key);
        mr->ibmr.rkey = mr->ibmr.lkey = hw_index_to_key(dev, key);

        if (mthca_is_memfree(dev)) {
                err = mthca_table_get(dev, dev->mr_table.mpt_table, key);
                if (err)
                        goto err_out_mpt_free;
        }

        mailbox = mthca_alloc_mailbox(dev, GFP_KERNEL);
        if (IS_ERR(mailbox)) {
                err = PTR_ERR(mailbox);
                goto err_out_table;
        }
        mpt_entry = mailbox->buf;

        mpt_entry->flags = cpu_to_be32(MTHCA_MPT_FLAG_SW_OWNS     |
                                       MTHCA_MPT_FLAG_MIO         |
                                       MTHCA_MPT_FLAG_REGION      |
                                       access);
        if (!mr->mtt)
                mpt_entry->flags |= cpu_to_be32(MTHCA_MPT_FLAG_PHYSICAL);

        mpt_entry->page_size = cpu_to_be32(buffer_size_shift - 12);
        mpt_entry->key       = cpu_to_be32(key);
        mpt_entry->pd        = cpu_to_be32(pd);
        mpt_entry->start     = cpu_to_be64(iova);
        mpt_entry->length    = cpu_to_be64(total_size);

        memset_startat(mpt_entry, 0, lkey);

        if (mr->mtt)
                mpt_entry->mtt_seg =
                        cpu_to_be64(dev->mr_table.mtt_base +
                                    mr->mtt->first_seg * dev->limits.mtt_seg_size);

        if (0) {
                mthca_dbg(dev, "Dumping MPT entry %08x:\n", mr->ibmr.lkey);
                for (i = 0; i < sizeof (struct mthca_mpt_entry) / 4; ++i) {
                        if (i % 4 == 0)
                                printk("[%02x] ", i * 4);
                        printk(" %08x", be32_to_cpu(((__be32 *) mpt_entry)[i]));
                        if ((i + 1) % 4 == 0)
                                printk("\n");
                }
        }

        err = mthca_SW2HW_MPT(dev, mailbox,
                              key & (dev->limits.num_mpts - 1));
        if (err) {
                mthca_warn(dev, "SW2HW_MPT failed (%d)\n", err);
                goto err_out_mailbox;
        }

        mthca_free_mailbox(dev, mailbox);
        return err;

err_out_mailbox:
        mthca_free_mailbox(dev, mailbox);

err_out_table:
        mthca_table_put(dev, dev->mr_table.mpt_table, key);

err_out_mpt_free:
        mthca_free(&dev->mr_table.mpt_alloc, key);
        return err;
}

int mthca_mr_alloc_notrans(struct mthca_dev *dev, u32 pd,
                           u32 access, struct mthca_mr *mr)
{
        mr->mtt = NULL;
        return mthca_mr_alloc(dev, pd, 12, 0, ~0ULL, access, mr);
}

int mthca_mr_alloc_phys(struct mthca_dev *dev, u32 pd,
                        u64 *buffer_list, int buffer_size_shift,
                        int list_len, u64 iova, u64 total_size,
                        u32 access, struct mthca_mr *mr)
{
        int err;

        mr->mtt = mthca_alloc_mtt(dev, list_len);
        if (IS_ERR(mr->mtt))
                return PTR_ERR(mr->mtt);

        err = mthca_write_mtt(dev, mr->mtt, 0, buffer_list, list_len);
        if (err) {
                mthca_free_mtt(dev, mr->mtt);
                return err;
        }

        err = mthca_mr_alloc(dev, pd, buffer_size_shift, iova,
                             total_size, access, mr);
        if (err)
                mthca_free_mtt(dev, mr->mtt);

        return err;
}

/* Free mr */
static void mthca_free_region(struct mthca_dev *dev, u32 lkey)
{
        mthca_table_put(dev, dev->mr_table.mpt_table,
                        key_to_hw_index(dev, lkey));

        mthca_free(&dev->mr_table.mpt_alloc, key_to_hw_index(dev, lkey));
}

void mthca_free_mr(struct mthca_dev *dev, struct mthca_mr *mr)
{
        int err;

        err = mthca_HW2SW_MPT(dev, NULL,
                              key_to_hw_index(dev, mr->ibmr.lkey) &
                              (dev->limits.num_mpts - 1));
        if (err)
                mthca_warn(dev, "HW2SW_MPT failed (%d)\n", err);

        mthca_free_region(dev, mr->ibmr.lkey);
        mthca_free_mtt(dev, mr->mtt);
}

int mthca_init_mr_table(struct mthca_dev *dev)
{
        phys_addr_t addr;
        int mpts, mtts, err, i;

        err = mthca_alloc_init(&dev->mr_table.mpt_alloc,
                               dev->limits.num_mpts,
                               ~0, dev->limits.reserved_mrws);
        if (err)
                return err;

        if (!mthca_is_memfree(dev) &&
            (dev->mthca_flags & MTHCA_FLAG_DDR_HIDDEN))
                dev->limits.fmr_reserved_mtts = 0;
        else
                dev->mthca_flags |= MTHCA_FLAG_FMR;

        if (dev->mthca_flags & MTHCA_FLAG_SINAI_OPT)
                mthca_dbg(dev, "Memory key throughput optimization activated.\n");

        err = mthca_buddy_init(&dev->mr_table.mtt_buddy,
                               fls(dev->limits.num_mtt_segs - 1));

        if (err)
                goto err_mtt_buddy;

        dev->mr_table.tavor_fmr.mpt_base = NULL;
        dev->mr_table.tavor_fmr.mtt_base = NULL;

        if (dev->limits.fmr_reserved_mtts) {
                i = fls(dev->limits.fmr_reserved_mtts - 1);

                if (i >= 31) {
                        mthca_warn(dev, "Unable to reserve 2^31 FMR MTTs.\n");
                        err = -EINVAL;
                        goto err_fmr_mpt;
                }
                mpts = mtts = 1 << i;
        } else {
                mtts = dev->limits.num_mtt_segs;
                mpts = dev->limits.num_mpts;
        }

        if (!mthca_is_memfree(dev) &&
            (dev->mthca_flags & MTHCA_FLAG_FMR)) {

                addr = pci_resource_start(dev->pdev, 4) +
                        ((pci_resource_len(dev->pdev, 4) - 1) &
                         dev->mr_table.mpt_base);

                dev->mr_table.tavor_fmr.mpt_base =
                        ioremap(addr, mpts * sizeof(struct mthca_mpt_entry));

                if (!dev->mr_table.tavor_fmr.mpt_base) {
                        mthca_warn(dev, "MPT ioremap for FMR failed.\n");
                        err = -ENOMEM;
                        goto err_fmr_mpt;
                }

                addr = pci_resource_start(dev->pdev, 4) +
                        ((pci_resource_len(dev->pdev, 4) - 1) &
                         dev->mr_table.mtt_base);

                dev->mr_table.tavor_fmr.mtt_base =
                        ioremap(addr, mtts * dev->limits.mtt_seg_size);
                if (!dev->mr_table.tavor_fmr.mtt_base) {
                        mthca_warn(dev, "MTT ioremap for FMR failed.\n");
                        err = -ENOMEM;
                        goto err_fmr_mtt;
                }
        }

        if (dev->limits.fmr_reserved_mtts) {
                err = mthca_buddy_init(&dev->mr_table.tavor_fmr.mtt_buddy, fls(mtts - 1));
                if (err)
                        goto err_fmr_mtt_buddy;

                /* Prevent regular MRs from using FMR keys */
                err = mthca_buddy_alloc(&dev->mr_table.mtt_buddy, fls(mtts - 1));
                if (err)
                        goto err_reserve_fmr;

                dev->mr_table.fmr_mtt_buddy =
                        &dev->mr_table.tavor_fmr.mtt_buddy;
        } else
                dev->mr_table.fmr_mtt_buddy = &dev->mr_table.mtt_buddy;

        /* FMR table is always the first, take reserved MTTs out of there */
        if (dev->limits.reserved_mtts) {
                i = fls(dev->limits.reserved_mtts - 1);

                if (mthca_alloc_mtt_range(dev, i,
                                          dev->mr_table.fmr_mtt_buddy) == -1) {
                        mthca_warn(dev, "MTT table of order %d is too small.\n",
                                  dev->mr_table.fmr_mtt_buddy->max_order);
                        err = -ENOMEM;
                        goto err_reserve_mtts;
                }
        }

        return 0;

err_reserve_mtts:
err_reserve_fmr:
        if (dev->limits.fmr_reserved_mtts)
                mthca_buddy_cleanup(&dev->mr_table.tavor_fmr.mtt_buddy);

err_fmr_mtt_buddy:
        if (dev->mr_table.tavor_fmr.mtt_base)
                iounmap(dev->mr_table.tavor_fmr.mtt_base);

err_fmr_mtt:
        if (dev->mr_table.tavor_fmr.mpt_base)
                iounmap(dev->mr_table.tavor_fmr.mpt_base);

err_fmr_mpt:
        mthca_buddy_cleanup(&dev->mr_table.mtt_buddy);

err_mtt_buddy:
        mthca_alloc_cleanup(&dev->mr_table.mpt_alloc);

        return err;
}

void mthca_cleanup_mr_table(struct mthca_dev *dev)
{
        /* XXX check if any MRs are still allocated? */
        if (dev->limits.fmr_reserved_mtts)
                mthca_buddy_cleanup(&dev->mr_table.tavor_fmr.mtt_buddy);

        mthca_buddy_cleanup(&dev->mr_table.mtt_buddy);

        if (dev->mr_table.tavor_fmr.mtt_base)
                iounmap(dev->mr_table.tavor_fmr.mtt_base);
        if (dev->mr_table.tavor_fmr.mpt_base)
                iounmap(dev->mr_table.tavor_fmr.mpt_base);

        mthca_alloc_cleanup(&dev->mr_table.mpt_alloc);
}