/*

 * OMAP on-chip MMC/SD host emulation.

 *

 * Copyright (C) 2006-2007 Andrzej Zaborowski  <balrog@zabor.org>

 *

 * 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 or

 * (at your option) version 3 of the License.

 *

 * 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.  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., 59 Temple Place, Suite 330, Boston,

 * MA 02111-1307 USA

 */

#include "hw.h"

#include "omap.h"

#include "sd.h"

struct omap_mmc_s {

    qemu_irq irq;

    qemu_irq *dma;

    qemu_irq coverswitch;

    omap_clk clk;

    SDState *card;

    uint16_t last_cmd;

    uint16_t sdio;

    uint16_t rsp[8];

    uint32_t arg;

    int lines;

    int dw;

    int mode;

    int enable;

    int be;

    int rev;

    uint16_t status;

    uint16_t mask;

    uint8_t cto;

    uint16_t dto;

    int clkdiv;

    uint16_t fifo[32];

    int fifo_start;

    int fifo_len;

    uint16_t blen;

    uint16_t blen_counter;

    uint16_t nblk;

    uint16_t nblk_counter;

    int tx_dma;

    int rx_dma;

    int af_level;

    int ae_level;

    int ddir;

    int transfer;

    int cdet_wakeup;

    int cdet_enable;

    int cdet_state;

    qemu_irq cdet;

};

static void omap_mmc_interrupts_update(struct omap_mmc_s *s)

{

    qemu_set_irq(s->irq, !!(s->status & s->mask));

}

static void omap_mmc_fifolevel_update(struct omap_mmc_s *host)

{

    if (!host->transfer && !host->fifo_len) {

        host->status &= 0xf3ff;

        return;

    }

    if (host->fifo_len > host->af_level && host->ddir) {

        if (host->rx_dma) {

            host->status &= 0xfbff;

            qemu_irq_raise(host->dma[1]);

        } else

            host->status |= 0x0400;

    } else {

        host->status &= 0xfbff;

        qemu_irq_lower(host->dma[1]);

    }

    if (host->fifo_len < host->ae_level && !host->ddir) {

        if (host->tx_dma) {

            host->status &= 0xf7ff;

            qemu_irq_raise(host->dma[0]);

        } else

            host->status |= 0x0800;

    } else {

        qemu_irq_lower(host->dma[0]);

        host->status &= 0xf7ff;

    }

}

typedef enum {

    sd_nore = 0,	/* no response */

    sd_r1,		/* normal response command */

    sd_r2,		/* CID, CSD registers */

    sd_r3,		/* OCR register */

    sd_r6 = 6,		/* Published RCA response */

    sd_r1b = -1,

} sd_rsp_type_t;

static void omap_mmc_command(struct omap_mmc_s *host, int cmd, int dir,

                sd_cmd_type_t type, int busy, sd_rsp_type_t resptype, int init)

{

    uint32_t rspstatus, mask;

    int rsplen, timeout;

    struct sd_request_s request;

    uint8_t response[16];

    if (init && cmd == 0) {

        host->status |= 0x0001;

        return;

    }

    if (resptype == sd_r1 && busy)

        resptype = sd_r1b;

    if (type == sd_adtc) {

        host->fifo_start = 0;

        host->fifo_len = 0;

        host->transfer = 1;

        host->ddir = dir;

    } else

        host->transfer = 0;

    timeout = 0;

    mask = 0;

    rspstatus = 0;

    request.cmd = cmd;

    request.arg = host->arg;

    request.crc = 0; /* FIXME */

    rsplen = sd_do_command(host->card, &request, response);

    /* TODO: validate CRCs */

    switch (resptype) {

    case sd_nore:

        rsplen = 0;

        break;

    case sd_r1:

    case sd_r1b:

        if (rsplen < 4) {

            timeout = 1;

            break;

        }

        rsplen = 4;

        mask = OUT_OF_RANGE | ADDRESS_ERROR | BLOCK_LEN_ERROR |

                ERASE_SEQ_ERROR | ERASE_PARAM | WP_VIOLATION |

                LOCK_UNLOCK_FAILED | COM_CRC_ERROR | ILLEGAL_COMMAND |

                CARD_ECC_FAILED | CC_ERROR | SD_ERROR |

                CID_CSD_OVERWRITE;

        if (host->sdio & (1 << 13))

            mask |= AKE_SEQ_ERROR;

        rspstatus = (response[0] << 24) | (response[1] << 16) |

                (response[2] << 8) | (response[3] << 0);

        break;

    case sd_r2:

        if (rsplen < 16) {

            timeout = 1;

            break;

        }

        rsplen = 16;

        break;

    case sd_r3:

        if (rsplen < 4) {

            timeout = 1;

            break;

        }

        rsplen = 4;

        rspstatus = (response[0] << 24) | (response[1] << 16) |

                (response[2] << 8) | (response[3] << 0);

        if (rspstatus & 0x80000000)

            host->status &= 0xe000;

        else

            host->status |= 0x1000;

        break;

    case sd_r6:

        if (rsplen < 4) {

            timeout = 1;

            break;

        }

        rsplen = 4;

        mask = 0xe000 | AKE_SEQ_ERROR;

        rspstatus = (response[2] << 8) | (response[3] << 0);

    }

    if (rspstatus & mask)

        host->status |= 0x4000;

    else

        host->status &= 0xb000;

    if (rsplen)

        for (rsplen = 0; rsplen < 8; rsplen ++)

            host->rsp[~rsplen & 7] = response[(rsplen << 1) | 1] |

                    (response[(rsplen << 1) | 0] << 8);

    if (timeout)

        host->status |= 0x0080;

    else if (cmd == 12)

        host->status |= 0x0005;	/* Makes it more real */

    else

        host->status |= 0x0001;

}

static void omap_mmc_transfer(struct omap_mmc_s *host)

{

    uint8_t value;

    if (!host->transfer)

        return;

    while (1) {

        if (host->ddir) {

            if (host->fifo_len > host->af_level)

                break;

            value = sd_read_data(host->card);

            host->fifo[(host->fifo_start + host->fifo_len) & 31] = value;

            if (-- host->blen_counter) {

                value = sd_read_data(host->card);

                host->fifo[(host->fifo_start + host->fifo_len) & 31] |=

                        value << 8;

                host->blen_counter --;

            }

            host->fifo_len ++;

        } else {

            if (!host->fifo_len)

                break;

            value = host->fifo[host->fifo_start] & 0xff;

            sd_write_data(host->card, value);

            if (-- host->blen_counter) {

                value = host->fifo[host->fifo_start] >> 8;

                sd_write_data(host->card, value);

                host->blen_counter --;

            }

            host->fifo_start ++;

            host->fifo_len --;

            host->fifo_start &= 31;

        }

        if (host->blen_counter == 0) {

            host->nblk_counter --;

            host->blen_counter = host->blen;

            if (host->nblk_counter == 0) {

                host->nblk_counter = host->nblk;

                host->transfer = 0;

                host->status |= 0x0008;

                break;

            }

        }

    }

}

static void omap_mmc_update(void *opaque)

{

    struct omap_mmc_s *s = opaque;

    omap_mmc_transfer(s);

    omap_mmc_fifolevel_update(s);

    omap_mmc_interrupts_update(s);

}

void omap_mmc_reset(struct omap_mmc_s *host)

{

    host->last_cmd = 0;

    memset(host->rsp, 0, sizeof(host->rsp));

    host->arg = 0;

    host->dw = 0;

    host->mode = 0;

    host->enable = 0;

    host->status = 0;

    host->mask = 0;

    host->cto = 0;

    host->dto = 0;

    host->fifo_len = 0;

    host->blen = 0;

    host->blen_counter = 0;

    host->nblk = 0;

    host->nblk_counter = 0;

    host->tx_dma = 0;

    host->rx_dma = 0;

    host->ae_level = 0x00;

    host->af_level = 0x1f;

    host->transfer = 0;

    host->cdet_wakeup = 0;

    host->cdet_enable = 0;

    qemu_set_irq(host->coverswitch, host->cdet_state);

    host->clkdiv = 0;

}

static uint32_t omap_mmc_read(void *opaque, target_phys_addr_t offset)

{

    uint16_t i;

    struct omap_mmc_s *s = (struct omap_mmc_s *) opaque;

    offset &= OMAP_MPUI_REG_MASK;

    switch (offset) {

    case 0x00:	/* MMC_CMD */

        return s->last_cmd;

    case 0x04:	/* MMC_ARGL */

        return s->arg & 0x0000ffff;

    case 0x08:	/* MMC_ARGH */

        return s->arg >> 16;

    case 0x0c:	/* MMC_CON */

        return (s->dw << 15) | (s->mode << 12) | (s->enable << 11) | 

                (s->be << 10) | s->clkdiv;

    case 0x10:	/* MMC_STAT */

        return s->status;

    case 0x14:	/* MMC_IE */

        return s->mask;

    case 0x18:	/* MMC_CTO */

        return s->cto;

    case 0x1c:	/* MMC_DTO */

        return s->dto;

    case 0x20:	/* MMC_DATA */

        /* TODO: support 8-bit access */

        i = s->fifo[s->fifo_start];

        if (s->fifo_len == 0) {

            printf("MMC: FIFO underrun\n");

            return i;

        }

        s->fifo_start ++;

        s->fifo_len --;

        s->fifo_start &= 31;

        omap_mmc_transfer(s);

        omap_mmc_fifolevel_update(s);

        omap_mmc_interrupts_update(s);

        return i;

    case 0x24:	/* MMC_BLEN */

        return s->blen_counter;

    case 0x28:	/* MMC_NBLK */

        return s->nblk_counter;

    case 0x2c:	/* MMC_BUF */

        return (s->rx_dma << 15) | (s->af_level << 8) |

            (s->tx_dma << 7) | s->ae_level;

    case 0x30:	/* MMC_SPI */

        return 0x0000;

    case 0x34:	/* MMC_SDIO */

        return (s->cdet_wakeup << 2) | (s->cdet_enable) | s->sdio;

    case 0x38:	/* MMC_SYST */

        return 0x0000;

    case 0x3c:	/* MMC_REV */

        return s->rev;

    case 0x40:	/* MMC_RSP0 */

    case 0x44:	/* MMC_RSP1 */

    case 0x48:	/* MMC_RSP2 */

    case 0x4c:	/* MMC_RSP3 */

    case 0x50:	/* MMC_RSP4 */

    case 0x54:	/* MMC_RSP5 */

    case 0x58:	/* MMC_RSP6 */

    case 0x5c:	/* MMC_RSP7 */

        return s->rsp[(offset - 0x40) >> 2];

    /* OMAP2-specific */

    case 0x60:	/* MMC_IOSR */

    case 0x64:	/* MMC_SYSC */

        return 0;

    case 0x68:	/* MMC_SYSS */

        return 1;						/* RSTD */

    }

    OMAP_BAD_REG(offset);

    return 0;

}

static void omap_mmc_write(void *opaque, target_phys_addr_t offset,

                uint32_t value)

{

    int i;

    struct omap_mmc_s *s = (struct omap_mmc_s *) opaque;

    offset &= OMAP_MPUI_REG_MASK;

    switch (offset) {

    case 0x00:	/* MMC_CMD */

        if (!s->enable)

            break;

        s->last_cmd = value;

        for (i = 0; i < 8; i ++)

            s->rsp[i] = 0x0000;

        omap_mmc_command(s, value & 63, (value >> 15) & 1,

                (sd_cmd_type_t) ((value >> 12) & 3),

                (value >> 11) & 1,

                (sd_rsp_type_t) ((value >> 8) & 7),

                (value >> 7) & 1);

        omap_mmc_update(s);

        break;

    case 0x04:	/* MMC_ARGL */

        s->arg &= 0xffff0000;

        s->arg |= 0x0000ffff & value;

        break;

    case 0x08:	/* MMC_ARGH */

        s->arg &= 0x0000ffff;

        s->arg |= value << 16;

        break;

    case 0x0c:	/* MMC_CON */

        s->dw = (value >> 15) & 1;

        s->mode = (value >> 12) & 3;

        s->enable = (value >> 11) & 1;

        s->be = (value >> 10) & 1;

        s->clkdiv = (value >> 0) & (s->rev >= 2 ? 0x3ff : 0xff);

        if (s->mode != 0)

            printf("SD mode %i unimplemented!\n", s->mode);

        if (s->be != 0)

            printf("SD FIFO byte sex unimplemented!\n");

        if (s->dw != 0 && s->lines < 4)

            printf("4-bit SD bus enabled\n");

        if (!s->enable)

            omap_mmc_reset(s);

        break;

    case 0x10:	/* MMC_STAT */

        s->status &= ~value;

        omap_mmc_interrupts_update(s);

        break;

    case 0x14:	/* MMC_IE */

        s->mask = value & 0x7fff;

        omap_mmc_interrupts_update(s);

        break;

    case 0x18:	/* MMC_CTO */

        s->cto = value & 0xff;

        if (s->cto > 0xfd && s->rev <= 1)

            printf("MMC: CTO of 0xff and 0xfe cannot be used!\n");

        break;

    case 0x1c:	/* MMC_DTO */

        s->dto = value & 0xffff;

        break;

    case 0x20:	/* MMC_DATA */

        /* TODO: support 8-bit access */

        if (s->fifo_len == 32)

            break;

        s->fifo[(s->fifo_start + s->fifo_len) & 31] = value;

        s->fifo_len ++;

        omap_mmc_transfer(s);

        omap_mmc_fifolevel_update(s);

        omap_mmc_interrupts_update(s);

        break;

    case 0x24:	/* MMC_BLEN */

        s->blen = (value & 0x07ff) + 1;

        s->blen_counter = s->blen;

        break;

    case 0x28:	/* MMC_NBLK */

        s->nblk = (value & 0x07ff) + 1;

        s->nblk_counter = s->nblk;

        s->blen_counter = s->blen;

        break;

    case 0x2c:	/* MMC_BUF */

        s->rx_dma = (value >> 15) & 1;

        s->af_level = (value >> 8) & 0x1f;

        s->tx_dma = (value >> 7) & 1;

        s->ae_level = value & 0x1f;

        if (s->rx_dma)

            s->status &= 0xfbff;

        if (s->tx_dma)

            s->status &= 0xf7ff;

        omap_mmc_fifolevel_update(s);

        omap_mmc_interrupts_update(s);

        break;

    /* SPI, SDIO and TEST modes unimplemented */

    case 0x30:	/* MMC_SPI (OMAP1 only) */

        break;

    case 0x34:	/* MMC_SDIO */

        s->sdio = value & (s->rev >= 2 ? 0xfbf3 : 0x2020);

        s->cdet_wakeup = (value >> 9) & 1;

        s->cdet_enable = (value >> 2) & 1;

        break;

    case 0x38:	/* MMC_SYST */

        break;

    case 0x3c:	/* MMC_REV */

    case 0x40:	/* MMC_RSP0 */

    case 0x44:	/* MMC_RSP1 */

    case 0x48:	/* MMC_RSP2 */

    case 0x4c:	/* MMC_RSP3 */

    case 0x50:	/* MMC_RSP4 */

    case 0x54:	/* MMC_RSP5 */

    case 0x58:	/* MMC_RSP6 */

    case 0x5c:	/* MMC_RSP7 */

        OMAP_RO_REG(offset);

        break;

    /* OMAP2-specific */

    case 0x60:	/* MMC_IOSR */