From e3598eddc3ec9a3deb321a2c04803246db4abb84 Mon Sep 17 00:00:00 2001 From: Richard Qin Date: Sun, 8 Nov 2026 06:43:18 +0800 Subject: [mubios] Add ATA Signed-off-by: Richard Qin --- mubios/drivers/ata.c | 93 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 93 insertions(+) create mode 100644 mubios/drivers/ata.c (limited to 'mubios/drivers') diff --git a/mubios/drivers/ata.c b/mubios/drivers/ata.c new file mode 100644 index 0000000..a0cd12a --- /dev/null +++ b/mubios/drivers/ata.c @@ -0,0 +1,93 @@ +/* + RCC-Project + + Copyright (C) 2026 Richard Qin + + This file is part of RCC-Project. + + RCC-Project 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 3 of the License, or (at your option) any + later version. + + RCC-Project 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 + RCC-Project; see the file COPYING. If not see + . + */ + +#include "bios.h" +#include "io.h" + +#define ATA_DATA 0x1F0u +#define ATA_SECTOR_COUNT 0x1F2u +#define ATA_LBA_LOW 0x1F3u +#define ATA_LBA_MID 0x1F4u +#define ATA_LBA_HIGH 0x1F5u +#define ATA_DRIVE 0x1F6u +#define ATA_STATUS 0x1F7u +#define ATA_COMMAND 0x1F7u + +#define ATA_STATUS_ERR 0x01u +#define ATA_STATUS_DRQ 0x08u +#define ATA_STATUS_BSY 0x80u + +#define ATA_CMD_READ_SECTORS 0x20u + +static u8 +ata_wait_not_busy (void) +{ + u8 status; + + do + { + status = io_in8 (ATA_STATUS); + } + while ((status & ATA_STATUS_BSY) != 0); + + return status; +} + +static void +ata_delay_400ns (void) +{ + io_in8 (ATA_STATUS); + io_in8 (ATA_STATUS); + io_in8 (ATA_STATUS); + io_in8 (ATA_STATUS); +} + +u8 +ata_read_sector28 (u32 lba, u16 *buffer) +{ + u8 status; + u16 index; + + status = ata_wait_not_busy (); + if ((status & ATA_STATUS_ERR) != 0) + return 1; + + io_out8 (ATA_DRIVE, (u8)(0xE0u | ((lba >> 24) & 0x0Fu))); + ata_delay_400ns (); + + io_out8 (ATA_SECTOR_COUNT, 1); + io_out8 (ATA_LBA_LOW, (u8)(lba & 0xFFu)); + io_out8 (ATA_LBA_MID, (u8)((lba >> 8) & 0xFFu)); + io_out8 (ATA_LBA_HIGH, (u8)((lba >> 16) & 0xFFu)); + io_out8 (ATA_COMMAND, ATA_CMD_READ_SECTORS); + + status = ata_wait_not_busy (); + if ((status & ATA_STATUS_ERR) != 0) + return 1; + + if ((status & ATA_STATUS_DRQ) == 0) + return 1; + + for (index = 0; index < 256; ++index) + buffer[index] = io_in16 (ATA_DATA); + + return 0; +} -- cgit v1.2.3