/**********************************************************************
 * Author: Cavium, Inc.
 *
 * Contact: support@cavium.com
 *          Please include "LiquidIO" in the subject.
 *
 * Copyright (c) 2003-2016 Cavium, Inc.
 *
 * This file is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, Version 2, as
 * published by the Free Software Foundation.
 *
 * This file is distributed in the hope that it will be useful, but
 * AS-IS and WITHOUT ANY WARRANTY; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, TITLE, or
 * NONINFRINGEMENT.  See the GNU General Public License for more
 * details.
 **********************************************************************/
#include <linux/netdevice.h>
#include "liquidio_common.h"
#include "octeon_droq.h"
#include "octeon_iq.h"
#include "response_manager.h"
#include "octeon_device.h"
#include "octeon_mem_ops.h"

#define MEMOPS_IDX   BAR1_INDEX_DYNAMIC_MAP

#ifdef __BIG_ENDIAN_BITFIELD
static inline void
octeon_toggle_bar1_swapmode(struct octeon_device *oct, u32 idx)
{
        u32 mask;

        mask = oct->fn_list.bar1_idx_read(oct, idx);
        mask = (mask & 0x2) ? (mask & ~2) : (mask | 2);
        oct->fn_list.bar1_idx_write(oct, idx, mask);
}
#else
#define octeon_toggle_bar1_swapmode(oct, idx)
#endif

static void
octeon_pci_fastwrite(struct octeon_device *oct, u8 __iomem *mapped_addr,
                     u8 *hostbuf, u32 len)
{
        while ((len) && ((unsigned long)mapped_addr) & 7) {
                writeb(*(hostbuf++), mapped_addr++);
                len--;
        }

        octeon_toggle_bar1_swapmode(oct, MEMOPS_IDX);

        while (len >= 8) {
                writeq(*((u64 *)hostbuf), mapped_addr);
                mapped_addr += 8;
                hostbuf += 8;
                len -= 8;
        }

        octeon_toggle_bar1_swapmode(oct, MEMOPS_IDX);

        while (len--)
                writeb(*(hostbuf++), mapped_addr++);
}

static void
octeon_pci_fastread(struct octeon_device *oct, u8 __iomem *mapped_addr,
                    u8 *hostbuf, u32 len)
{
        while ((len) && ((unsigned long)mapped_addr) & 7) {
                *(hostbuf++) = readb(mapped_addr++);
                len--;
        }

        octeon_toggle_bar1_swapmode(oct, MEMOPS_IDX);

        while (len >= 8) {
                *((u64 *)hostbuf) = readq(mapped_addr);
                mapped_addr += 8;
                hostbuf += 8;
                len -= 8;
        }

        octeon_toggle_bar1_swapmode(oct, MEMOPS_IDX);

        while (len--)
                *(hostbuf++) = readb(mapped_addr++);
}

/* Core mem read/write with temporary bar1 settings. */
/* op = 1 to read, op = 0 to write. */
static void
__octeon_pci_rw_core_mem(struct octeon_device *oct, u64 addr,
                         u8 *hostbuf, u32 len, u32 op)
{
        u32 copy_len = 0, index_reg_val = 0;
        unsigned long flags;
        u8 __iomem *mapped_addr;
        u64 static_mapping_base;

        static_mapping_base = oct->console_nb_info.dram_region_base;

        if (static_mapping_base &&
            static_mapping_base == (addr & ~(OCTEON_BAR1_ENTRY_SIZE - 1ULL))) {
                int bar1_index = oct->console_nb_info.bar1_index;

                mapped_addr = oct->mmio[1].hw_addr
                        + (bar1_index << ilog2(OCTEON_BAR1_ENTRY_SIZE))
                        + (addr & (OCTEON_BAR1_ENTRY_SIZE - 1ULL));

                if (op)
                        octeon_pci_fastread(oct, mapped_addr, hostbuf, len);
                else
                        octeon_pci_fastwrite(oct, mapped_addr, hostbuf, len);

                return;
        }

        spin_lock_irqsave(&oct->mem_access_lock, flags);

        /* Save the original index reg value. */
        index_reg_val = oct->fn_list.bar1_idx_read(oct, MEMOPS_IDX);
        do {
                oct->fn_list.bar1_idx_setup(oct, addr, MEMOPS_IDX, 1);
                mapped_addr = oct->mmio[1].hw_addr
                    + (MEMOPS_IDX << 22) + (addr & 0x3fffff);

                /* If operation crosses a 4MB boundary, split the transfer
                 * at the 4MB
                 * boundary.
                 */
                if (((addr + len - 1) & ~(0x3fffff)) != (addr & ~(0x3fffff))) {
                        copy_len = (u32)(((addr & ~(0x3fffff)) +
                                   (MEMOPS_IDX << 22)) - addr);
                } else {
                        copy_len = len;
                }

                if (op) {       /* read from core */
                        octeon_pci_fastread(oct, mapped_addr, hostbuf,
                                            copy_len);
                } else {
                        octeon_pci_fastwrite(oct, mapped_addr, hostbuf,
                                             copy_len);
                }

                len -= copy_len;
                addr += copy_len;
                hostbuf += copy_len;

        } while (len);

        oct->fn_list.bar1_idx_write(oct, MEMOPS_IDX, index_reg_val);

        spin_unlock_irqrestore(&oct->mem_access_lock, flags);
}

void
octeon_pci_read_core_mem(struct octeon_device *oct,
                         u64 coreaddr,
                         u8 *buf,
                         u32 len)
{
        __octeon_pci_rw_core_mem(oct, coreaddr, buf, len, 1);
}
EXPORT_SYMBOL_GPL(octeon_pci_read_core_mem);

void
octeon_pci_write_core_mem(struct octeon_device *oct,
                          u64 coreaddr,
                          const u8 *buf,
                          u32 len)
{
        __octeon_pci_rw_core_mem(oct, coreaddr, (u8 *)buf, len, 0);
}
EXPORT_SYMBOL_GPL(octeon_pci_write_core_mem);

u64 octeon_read_device_mem64(struct octeon_device *oct, u64 coreaddr)
{
        __be64 ret;

        __octeon_pci_rw_core_mem(oct, coreaddr, (u8 *)&ret, 8, 1);

        return be64_to_cpu(ret);
}
EXPORT_SYMBOL_GPL(octeon_read_device_mem64);

u32 octeon_read_device_mem32(struct octeon_device *oct, u64 coreaddr)
{
        __be32 ret;

        __octeon_pci_rw_core_mem(oct, coreaddr, (u8 *)&ret, 4, 1);

        return be32_to_cpu(ret);
}
EXPORT_SYMBOL_GPL(octeon_read_device_mem32);

void octeon_write_device_mem32(struct octeon_device *oct, u64 coreaddr,
                               u32 val)
{
        __be32 t = cpu_to_be32(val);

        __octeon_pci_rw_core_mem(oct, coreaddr, (u8 *)&t, 4, 0);
}
EXPORT_SYMBOL_GPL(octeon_write_device_mem32);