/*
 *    Disk Array driver for Compaq SMART2 Controllers
 *    Copyright 1998 Compaq Computer Corporation
 *
 *    This program is free software; you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation; either version 2 of the License, or
 *    (at your option) any later version.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
 *    NON INFRINGEMENT.  See the GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program; if not, write to the Free Software
 *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *    Questions/Comments/Bugfixes to iss_storagedev@hp.com
 *
 *    If you want to make changes, improve or add functionality to this
 *    driver, you'll probably need the Compaq Array Controller Interface
 *    Specificiation (Document number ECG086/1198)
 */

/*
 * This file contains the controller communication implementation for
 * Compaq SMART-1 and SMART-2 controllers.  To the best of my knowledge,
 * this should support:
 *
 *  PCI:
 *  SMART-2/P, SMART-2DH, SMART-2SL, SMART-221, SMART-3100ES, SMART-3200
 *  Integerated SMART Array Controller, SMART-4200, SMART-4250ES
 *
 *  EISA:
 *  SMART-2/E, SMART, IAES, IDA-2, IDA
 */

/*
 * Memory mapped FIFO interface (SMART 42xx cards)
 */
static void smart4_submit_command(ctlr_info_t *h, cmdlist_t *c)
{
        writel(c->busaddr, h->vaddr + S42XX_REQUEST_PORT_OFFSET);
}

/*  
 *  This card is the opposite of the other cards.  
 *   0 turns interrupts on... 
 *   0x08 turns them off... 
 */
static void smart4_intr_mask(ctlr_info_t *h, unsigned long val)
{
        if (val) 
        { /* Turn interrupts on */
                writel(0, h->vaddr + S42XX_REPLY_INTR_MASK_OFFSET);
        } else /* Turn them off */
        {
                writel( S42XX_INTR_OFF, 
                        h->vaddr + S42XX_REPLY_INTR_MASK_OFFSET);
        }
}

/*
 *  For older cards FIFO Full = 0. 
 *  On this card 0 means there is room, anything else FIFO Full. 
 * 
 */ 
static unsigned long smart4_fifo_full(ctlr_info_t *h)
{
        
        return (!readl(h->vaddr + S42XX_REQUEST_PORT_OFFSET));
}

/* This type of controller returns -1 if the fifo is empty, 
 *    Not 0 like the others.
 *    And we need to let it know we read a value out 
 */ 
static unsigned long smart4_completed(ctlr_info_t *h)
{
        long register_value 
                = readl(h->vaddr + S42XX_REPLY_PORT_OFFSET);

        /* Fifo is empty */
        if( register_value == 0xffffffff)
                return 0;       

        /* Need to let it know we got the reply */
        /* We do this by writing a 0 to the port we just read from */
        writel(0, h->vaddr + S42XX_REPLY_PORT_OFFSET);

        return ((unsigned long) register_value); 
}

 /*
 *  This hardware returns interrupt pending at a different place and 
 *  it does not tell us if the fifo is empty, we will have check  
 *  that by getting a 0 back from the comamnd_completed call. 
 */
static unsigned long smart4_intr_pending(ctlr_info_t *h)
{
        unsigned long register_value  = 
                readl(h->vaddr + S42XX_INTR_STATUS);

        if( register_value &  S42XX_INTR_PENDING) 
                return  FIFO_NOT_EMPTY; 
        return 0 ;
}

static struct access_method smart4_access = {
        smart4_submit_command,
        smart4_intr_mask,
        smart4_fifo_full,
        smart4_intr_pending,
        smart4_completed,
};

/*
 * Memory mapped FIFO interface (PCI SMART2 and SMART 3xxx cards)
 */
static void smart2_submit_command(ctlr_info_t *h, cmdlist_t *c)
{
        writel(c->busaddr, h->vaddr + COMMAND_FIFO);
}

static void smart2_intr_mask(ctlr_info_t *h, unsigned long val)
{
        writel(val, h->vaddr + INTR_MASK);
}

static unsigned long smart2_fifo_full(ctlr_info_t *h)
{
        return readl(h->vaddr + COMMAND_FIFO);
}

static unsigned long smart2_completed(ctlr_info_t *h)
{
        return readl(h->vaddr + COMMAND_COMPLETE_FIFO);
}

static unsigned long smart2_intr_pending(ctlr_info_t *h)
{
        return readl(h->vaddr + INTR_PENDING);
}

static struct access_method smart2_access = {
        smart2_submit_command,
        smart2_intr_mask,
        smart2_fifo_full,
        smart2_intr_pending,
        smart2_completed,
};

/*
 *  IO access for SMART-2/E cards
 */
static void smart2e_submit_command(ctlr_info_t *h, cmdlist_t *c)
{
        outl(c->busaddr, h->io_mem_addr + COMMAND_FIFO);
}

static void smart2e_intr_mask(ctlr_info_t *h, unsigned long val)
{
        outl(val, h->io_mem_addr + INTR_MASK);
}

static unsigned long smart2e_fifo_full(ctlr_info_t *h)
{
        return inl(h->io_mem_addr + COMMAND_FIFO);
}

static unsigned long smart2e_completed(ctlr_info_t *h)
{
        return inl(h->io_mem_addr + COMMAND_COMPLETE_FIFO);
}

static unsigned long smart2e_intr_pending(ctlr_info_t *h)
{
        return inl(h->io_mem_addr + INTR_PENDING);
}

static struct access_method smart2e_access = {
        smart2e_submit_command,
        smart2e_intr_mask,
        smart2e_fifo_full,
        smart2e_intr_pending,
        smart2e_completed,
};

/*
 *  IO access for older SMART-1 type cards
 */
#define SMART1_SYSTEM_MASK              0xC8E
#define SMART1_SYSTEM_DOORBELL          0xC8F
#define SMART1_LOCAL_MASK               0xC8C
#define SMART1_LOCAL_DOORBELL           0xC8D
#define SMART1_INTR_MASK                0xC89
#define SMART1_LISTADDR                 0xC90
#define SMART1_LISTLEN                  0xC94
#define SMART1_TAG                      0xC97
#define SMART1_COMPLETE_ADDR            0xC98
#define SMART1_LISTSTATUS               0xC9E

#define CHANNEL_BUSY                    0x01
#define CHANNEL_CLEAR                   0x02

static void smart1_submit_command(ctlr_info_t *h, cmdlist_t *c)
{
        /*
         * This __u16 is actually a bunch of control flags on SMART
         * and below.  We want them all to be zero.
         */
        c->hdr.size = 0;

        outb(CHANNEL_CLEAR, h->io_mem_addr + SMART1_SYSTEM_DOORBELL);

        outl(c->busaddr, h->io_mem_addr + SMART1_LISTADDR);
        outw(c->size, h->io_mem_addr + SMART1_LISTLEN);

        outb(CHANNEL_BUSY, h->io_mem_addr + SMART1_LOCAL_DOORBELL);
}

static void smart1_intr_mask(ctlr_info_t *h, unsigned long val)
{
        if (val == 1) {
                outb(0xFD, h->io_mem_addr + SMART1_SYSTEM_DOORBELL);
                outb(CHANNEL_BUSY, h->io_mem_addr + SMART1_LOCAL_DOORBELL);
                outb(0x01, h->io_mem_addr + SMART1_INTR_MASK);
                outb(0x01, h->io_mem_addr + SMART1_SYSTEM_MASK);
        } else {
                outb(0, h->io_mem_addr + 0xC8E);
        }
}

static unsigned long smart1_fifo_full(ctlr_info_t *h)
{
        unsigned char chan;
        chan = inb(h->io_mem_addr + SMART1_SYSTEM_DOORBELL) & CHANNEL_CLEAR;
        return chan;
}

static unsigned long smart1_completed(ctlr_info_t *h)
{
        unsigned char status;
        unsigned long cmd;

        if (inb(h->io_mem_addr + SMART1_SYSTEM_DOORBELL) & CHANNEL_BUSY) {
                outb(CHANNEL_BUSY, h->io_mem_addr + SMART1_SYSTEM_DOORBELL);

                cmd = inl(h->io_mem_addr + SMART1_COMPLETE_ADDR);
                status = inb(h->io_mem_addr + SMART1_LISTSTATUS);

                outb(CHANNEL_CLEAR, h->io_mem_addr + SMART1_LOCAL_DOORBELL);

                /*
                 * this is x86 (actually compaq x86) only, so it's ok
                 */
                if (cmd) ((cmdlist_t*)bus_to_virt(cmd))->req.hdr.rcode = status;
        } else {
                cmd = 0;
        }
        return cmd;
}

static unsigned long smart1_intr_pending(ctlr_info_t *h)
{
        unsigned char chan;
        chan = inb(h->io_mem_addr + SMART1_SYSTEM_DOORBELL) & CHANNEL_BUSY;
        return chan;
}

static struct access_method smart1_access = {
        smart1_submit_command,
        smart1_intr_mask,
        smart1_fifo_full,
        smart1_intr_pending,
        smart1_completed,
};