source: mainline/uspace/srv/bd/ata_bd/ata_bd.c@ d9f4c76

/*
 * Copyright (c) 2009 Jiri Svoboda
 * All rights reserved.
 *
 * 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 name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup bd
 * @{
 */

/**
 * @file
 * @brief ATA disk driver
 *
 * This driver currently works only with CHS addressing and uses PIO.
 * Currently based on the (now obsolete) ANSI X3.221-1994 (ATA-1) standard.
 * At this point only reading is possible, not writing.
 */

#include <stdio.h>
#include <libarch/ddi.h>
#include <ddi.h>
#include <ipc/ipc.h>
#include <ipc/bd.h>
#include <async.h>
#include <as.h>
#include <futex.h>
#include <devmap.h>
#include <sys/types.h>
#include <errno.h>
#include <bool.h>

#include "ata_bd.h"

#define NAME "ata_bd"

static const size_t block_size = 512;
static size_t comm_size;

static uintptr_t cmd_physical = 0x1f0;
static uintptr_t ctl_physical = 0x170;
static ata_cmd_t *cmd;
static ata_ctl_t *ctl;

static dev_handle_t dev_handle[MAX_DISKS];

static atomic_t dev_futex = FUTEX_INITIALIZER;

static disk_t disk[MAX_DISKS];

static int ata_bd_init(void);
static void ata_bd_connection(ipc_callid_t iid, ipc_call_t *icall);
static int ata_bd_rdwr(int disk_id, ipcarg_t method, off_t offset, off_t size,
    void *buf);
static int ata_bd_read_block(int disk_id, uint64_t blk_idx, size_t blk_cnt,
    void *buf);
static int ata_bd_write_block(int disk_id, uint64_t blk_idx, size_t blk_cnt,
    const void *buf);
static int drive_identify(int drive_id, disk_t *d);

int main(int argc, char **argv)
{
        uint8_t status;
        char name[16];
        int i, rc;
        int n_disks;

        printf(NAME ": ATA disk driver\n");

        printf("cmd_physical = 0x%x\n", cmd_physical);
        printf("ctl_physical = 0x%x\n", ctl_physical);

        if (ata_bd_init() != EOK)
                return -1;

        /* Put drives to reset, disable interrupts. */
        printf("Reset drives...\n");
        pio_write_8(&ctl->device_control, DCR_SRST);
        /* FIXME: Find out how to do this properly. */
        async_usleep(100);
        pio_write_8(&ctl->device_control, 0);

        do {
                status = pio_read_8(&cmd->status);
        } while ((status & SR_BSY) != 0);
        printf("Done\n");

        printf("Status = 0x%x\n", pio_read_8(&cmd->status));

        (void) drive_identify(0, &disk[0]);
        (void) drive_identify(1, &disk[1]);

        n_disks = 0;

        for (i = 0; i < MAX_DISKS; i++) {
                /* Skip unattached drives. */
                if (disk[i].present == false)
                        continue;

                snprintf(name, 16, "disk%d", i);
                rc = devmap_device_register(name, &dev_handle[i]);
                if (rc != EOK) {
                        devmap_hangup_phone(DEVMAP_DRIVER);
                        printf(NAME ": Unable to register device %s.\n",
                                name);
                        return rc;
                }
                ++n_disks;
        }

        if (n_disks == 0) {
                printf("No disks detected.\n");
                return -1;
        }

        printf(NAME ": Accepting connections\n");
        async_manager();

        /* Not reached */
        return 0;
}

static int drive_identify(int disk_id, disk_t *d)
{
        uint16_t data;
        uint8_t status;
        int i;

        printf("Identify drive %d\n", disk_id);
        pio_write_8(&cmd->drive_head, ((disk_id != 0) ? DHR_DRV : 0));
        async_usleep(100);
        pio_write_8(&cmd->command, CMD_IDENTIFY_DRIVE);

        status = pio_read_8(&cmd->status);
        printf("Status = 0x%x\n", status);

        d->present = false;

        /*
         * Detect if drive is present. This is Qemu only! Need to
         * do the right thing to work with real drives.
         */
        if ((status & SR_DRDY) == 0) {
                printf("None attached.\n");
                return ENOENT;
        }

        for (i = 0; i < block_size / 2; i++) {
                do {
                        status = pio_read_8(&cmd->status);
                } while ((status & SR_DRDY) == 0);

                data = pio_read_16(&cmd->data_port);

                switch (i) {
                case 1: d->cylinders = data; break;
                case 3: d->heads = data; break;
                case 6: d->sectors = data; break;
                }
        }

        printf("\n\nStatus = 0x%x\n", pio_read_8(&cmd->status));

        d->blocks = d->cylinders * d->heads * d->sectors;

        printf("Geometry: %u cylinders, %u heads, %u sectors\n",
                d->cylinders, d->heads, d->sectors);

        d->present = true;

        return EOK;
}

static int ata_bd_init(void)
{
        void *vaddr;
        int rc;

        rc = devmap_driver_register(NAME, ata_bd_connection);
        if (rc < 0) {
                printf(NAME ": Unable to register driver.\n");
                return rc;
        }

        rc = pio_enable((void *) cmd_physical, sizeof(ata_cmd_t), &vaddr);
        if (rc != EOK) {
                printf(NAME ": Could not initialize device I/O space.\n");
                return rc;
        }

        cmd = vaddr;

        rc = pio_enable((void *) ctl_physical, sizeof(ata_ctl_t), &vaddr);
        if (rc != EOK) {
                printf(NAME ": Could not initialize device I/O space.\n");
                return rc;
        }

        ctl = vaddr;


        return EOK;
}

static void ata_bd_connection(ipc_callid_t iid, ipc_call_t *icall)
{
        void *fs_va = NULL;
        ipc_callid_t callid;
        ipc_call_t call;
        ipcarg_t method;
        dev_handle_t dh;
        int flags;
        int retval;
        off_t idx;
        off_t size;
        int disk_id, i;

        /* Get the device handle. */
        dh = IPC_GET_ARG1(*icall);

        /* Determine which disk device is the client connecting to. */
        disk_id = -1;
        for (i = 0; i < MAX_DISKS; i++)
                if (dev_handle[i] == dh)
                        disk_id = i;

        if (disk_id < 0 || disk[disk_id].present == false) {
                ipc_answer_0(iid, EINVAL);
                return;
        }

        /* Answer the IPC_M_CONNECT_ME_TO call. */
        ipc_answer_0(iid, EOK);

        if (!ipc_share_out_receive(&callid, &comm_size, &flags)) {
                ipc_answer_0(callid, EHANGUP);
                return;
        }

        fs_va = as_get_mappable_page(comm_size);
        if (fs_va == NULL) {
                ipc_answer_0(callid, EHANGUP);
                return;
        }

        (void) ipc_share_out_finalize(callid, fs_va);

        while (1) {
                callid = async_get_call(&call);
                method = IPC_GET_METHOD(call);
                switch (method) {
                case IPC_M_PHONE_HUNGUP:
                        /* The other side has hung up. */
                        ipc_answer_0(callid, EOK);
                        return;
                case BD_READ_BLOCK:
                case BD_WRITE_BLOCK:
                        idx = IPC_GET_ARG1(call);
                        size = IPC_GET_ARG2(call);
                        if (size > comm_size) {
                                retval = EINVAL;
                                break;
                        }
                        retval = ata_bd_rdwr(disk_id, method, idx,
                            size, fs_va);
                        break;
                default:
                        retval = EINVAL;
                        break;
                }
                ipc_answer_0(callid, retval);
        }
}

static int ata_bd_rdwr(int disk_id, ipcarg_t method, off_t blk_idx, off_t size,
    void *buf)
{
        int rc;
        off_t now;

        while (size > 0) {
                now = size < block_size ? size : (off_t) block_size;
                if (now != block_size)
                        return EINVAL;

                if (method == BD_READ_BLOCK)
                        rc = ata_bd_read_block(disk_id, blk_idx, 1, buf);
                else
                        rc = ata_bd_write_block(disk_id, blk_idx, 1, buf);

                if (rc != EOK)
                        return rc;

                buf += block_size;
                blk_idx++;

                if (size > block_size)
                        size -= block_size;
                else
                        size = 0;
        }

        return EOK;
}


static int ata_bd_read_block(int disk_id, uint64_t blk_idx, size_t blk_cnt,
    void *buf)
{
        size_t i;
        uint16_t data;
        uint8_t status;
        uint64_t c, h, s;
        uint64_t idx;
        uint8_t drv_head;
        disk_t *d;

        d = &disk[disk_id];

        /* Check device bounds. */
        if (blk_idx >= d->blocks)
                return EINVAL;

        /* Compute CHS. */
        c = blk_idx / (d->heads * d->sectors);
        idx = blk_idx % (d->heads * d->sectors);

        h = idx / d->sectors;
        s = 1 + (idx % d->sectors);

        /* New value for Drive/Head register */
        drv_head =
            ((disk_id != 0) ? DHR_DRV : 0) |
            (h & 0x0f);

        futex_down(&dev_futex);

        /* Program a Read Sectors operation. */

        pio_write_8(&cmd->drive_head, drv_head);
        pio_write_8(&cmd->sector_count, 1);
        pio_write_8(&cmd->sector_number, s);
        pio_write_8(&cmd->cylinder_low, c & 0xff);
        pio_write_8(&cmd->cylinder_high, c >> 16);
        pio_write_8(&cmd->command, CMD_READ_SECTORS);

        /* Read data from the disk buffer. */

        for (i = 0; i < block_size / 2; i++) {
                do {
                        status = pio_read_8(&cmd->status);
                } while ((status & SR_DRDY) == 0);

                data = pio_read_16(&cmd->data_port);
                ((uint16_t *) buf)[i] = data;
        }

        futex_up(&dev_futex);
        return EOK;
}

static int ata_bd_write_block(int disk_id, uint64_t blk_idx, size_t blk_cnt,
    const void *buf)
{
        size_t i;
        uint8_t status;
        uint64_t c, h, s;
        uint64_t idx;
        uint8_t drv_head;
        disk_t *d;

        d = &disk[disk_id];

        /* Check device bounds. */
        if (blk_idx >= d->blocks)
                return EINVAL;

        /* Compute CHS. */
        c = blk_idx / (d->heads * d->sectors);
        idx = blk_idx % (d->heads * d->sectors);

        h = idx / d->sectors;
        s = 1 + (idx % d->sectors);

        /* New value for Drive/Head register */
        drv_head =
            ((disk_id != 0) ? DHR_DRV : 0) |
            (h & 0x0f);

        futex_down(&dev_futex);

        /* Program a Read Sectors operation. */

        pio_write_8(&cmd->drive_head, drv_head);
        pio_write_8(&cmd->sector_count, 1);
        pio_write_8(&cmd->sector_number, s);
        pio_write_8(&cmd->cylinder_low, c & 0xff);
        pio_write_8(&cmd->cylinder_high, c >> 16);
        pio_write_8(&cmd->command, CMD_WRITE_SECTORS);

        /* Write data to the disk buffer. */

        for (i = 0; i < block_size / 2; i++) {
                do {
                        status = pio_read_8(&cmd->status);
                } while ((status & SR_DRDY) == 0);

                pio_write_16(&cmd->data_port, ((uint16_t *) buf)[i]);
        }

        futex_up(&dev_futex);
        return EOK;
}


/**
 * @}
 */