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/*
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 * Ramdisk driver for Tegra X1
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 *
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 * Copyright (c) 2019-2021 CTCaer
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 *
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 * This program is free software; you can redistribute it and/or modify it
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 * under the terms and conditions of the GNU General Public License,
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 * version 2, as published by the Free Software Foundation.
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 *
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 * This program is distributed in the hope it will be useful, but WITHOUT
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
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 * more details.
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 *
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 * You should have received a copy of the GNU General Public License
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 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
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 */
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#include <string.h>
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#include "ramdisk.h"
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#include <libs/fatfs/diskio.h>
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#include <libs/fatfs/ff.h>
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#include <mem/heap.h>
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#include <utils/types.h>
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#include <memory_map.h>
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static u32 disk_size = 0;
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int ram_disk_init(void *ram_fs, u32 ramdisk_size)
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{
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	int res = 0;
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	disk_size = ramdisk_size;
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	FATFS *ram_fatfs = (FATFS *)ram_fs;
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	// If ramdisk is not raw, format it.
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	if (ram_fs)
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	{
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		u8 *buf = malloc(0x400000);
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		// Set ramdisk size.
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		ramdisk_size >>= 9;
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		disk_set_info(DRIVE_RAM, SET_SECTOR_COUNT, &ramdisk_size);
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		// Unmount ramdisk.
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		f_mount(NULL, "ram:", 1);
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		// Format as exFAT w/ 32KB cluster with no MBR.
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		res = f_mkfs("ram:", FM_EXFAT | FM_SFD, RAMDISK_CLUSTER_SZ, buf, 0x400000);
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		// Mount ramdisk.
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		if (!res)
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			res = f_mount(ram_fatfs, "ram:", 1);
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		free(buf);
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	}
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	return res;
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}
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int ram_disk_read(u32 sector, u32 sector_count, void *buf)
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{
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	u32 sector_off = RAM_DISK_ADDR + (sector << 9);
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	u32 bytes_count = sector_count << 9;
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	if ((sector_off - RAM_DISK_ADDR) > disk_size)
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		return 1;
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	memcpy(buf, (void *)sector_off, bytes_count);
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	return 0;
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}
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int ram_disk_write(u32 sector, u32 sector_count, const void *buf)
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{
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	u32 sector_off = RAM_DISK_ADDR + (sector << 9);
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	u32 bytes_count = sector_count << 9;
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	if ((sector_off - RAM_DISK_ADDR) > disk_size)
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		return 1;
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	memcpy((void *)sector_off, buf, bytes_count);
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	return 0;
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}
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