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-rw-r--r--bootloader/fat32format.c504
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diff --git a/bootloader/fat32format.c b/bootloader/fat32format.c
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+/***************************************************************************
+ * __________ __ ___.
+ * Open \______ \ ____ ____ | | _\_ |__ _______ ___
+ * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
+ * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
+ * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
+ * \/ \/ \/ \/ \/
+ * $Id: fat32format.c 30351 2011-08-25 19:58:47Z thomasjfox $
+ *
+ *
+ * FAT32 formatting functions. Based on:
+ *
+ * Fat32 formatter version 1.03
+ * (c) Tom Thornhill 2005
+ * This software is covered by the GPL.
+ * By using this tool, you agree to absolve Ridgecrop of an liabilities for
+ * lost data.
+ * Please backup any data you value before using this tool.
+ *
+ *
+ * Modified June 2007 by Dave Chapman for use in ipodpatcher
+ * Modified September 2011 by Frank Gevaerts for use in sansa eraser
+ *
+ *
+ * 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include "common.h"
+#include "cpu.h"
+#include "file.h"
+#include "system.h"
+#include "kernel.h"
+#include "lcd.h"
+#include "font.h"
+#include "storage.h"
+#include "button.h"
+#include "disk.h"
+#include "crc32-mi4.h"
+#include <string.h>
+#include "i2c.h"
+#include "backlight-target.h"
+#include "power.h"
+
+#define SECTOR_SIZE 512
+
+/* The following functions are not the most efficient, but are
+ self-contained and don't require needing to know endianness of CPU
+ at compile-time.
+
+ Note that htole16/htole32 exist on some platforms, so for
+ simplicity we use different names.
+
+*/
+
+static uint16_t rb_htole16(uint16_t x)
+{
+ uint16_t test = 0x1234;
+ unsigned char* p = (unsigned char*)&test;
+
+ if (p[0]==0x12) {
+ /* Big-endian */
+ return swap16(x);
+ } else {
+ return x;
+ }
+}
+
+static uint32_t rb_htole32(uint32_t x)
+{
+ uint32_t test = 0x12345678;
+ unsigned char* p = (unsigned char*)&test;
+
+ if (p[0]==0x12) {
+ /* Big-endian */
+ return swap32(x);
+ } else {
+ return x;
+ }
+}
+
+
+/* A large aligned buffer for disk I/O */
+unsigned char sectorbuf[128*SECTOR_SIZE];
+
+/* TODO: Pass these as parameters to the various create_ functions */
+
+/* can be zero for default or 1,2,4,8,16,32 or 64 */
+static int sectors_per_cluster = 0;
+
+/* Recommended values */
+static uint32_t ReservedSectCount = 32;
+static uint32_t NumFATs = 2;
+static uint32_t BackupBootSect = 6;
+static uint32_t VolumeId=0; /* calculated before format */
+
+/* Calculated later */
+static uint32_t FatSize=0;
+static uint32_t BytesPerSect=0;
+static uint32_t SectorsPerCluster=0;
+static uint32_t TotalSectors=0;
+static uint32_t SystemAreaSize=0;
+static uint32_t UserAreaSize=0;
+static uint8_t VolId[12] = "NO NAME ";
+
+
+struct FAT_BOOTSECTOR32
+{
+ /* Common fields. */
+ uint8_t sJmpBoot[3];
+ char sOEMName[8];
+ uint16_t wBytsPerSec;
+ uint8_t bSecPerClus;
+ uint16_t wRsvdSecCnt;
+ uint8_t bNumFATs;
+ uint16_t wRootEntCnt;
+ uint16_t wTotSec16; /* if zero, use dTotSec32 instead */
+ uint8_t bMedia;
+ uint16_t wFATSz16;
+ uint16_t wSecPerTrk;
+ uint16_t wNumHeads;
+ uint32_t dHiddSec;
+ uint32_t dTotSec32;
+
+ /* Fat 32/16 only */
+ uint32_t dFATSz32;
+ uint16_t wExtFlags;
+ uint16_t wFSVer;
+ uint32_t dRootClus;
+ uint16_t wFSInfo;
+ uint16_t wBkBootSec;
+ uint8_t Reserved[12];
+ uint8_t bDrvNum;
+ uint8_t Reserved1;
+ uint8_t bBootSig; /* == 0x29 if next three fields are ok */
+ uint32_t dBS_VolID;
+ uint8_t sVolLab[11];
+ uint8_t sBS_FilSysType[8];
+} __attribute__((packed));
+
+struct FAT_FSINFO {
+ uint32_t dLeadSig; // 0x41615252
+ uint8_t sReserved1[480]; // zeros
+ uint32_t dStrucSig; // 0x61417272
+ uint32_t dFree_Count; // 0xFFFFFFFF
+ uint32_t dNxt_Free; // 0xFFFFFFFF
+ uint8_t sReserved2[12]; // zeros
+ uint32_t dTrailSig; // 0xAA550000
+} __attribute__((packed));
+
+
+/* Write "count" zero sectors, starting at sector "sector" */
+static int zero_sectors(uint32_t sector, int count)
+{
+ int n;
+
+ memset(sectorbuf, 0, 128 * SECTOR_SIZE);
+
+ /* Write 128 sectors at a time */
+ while (count) {
+ if (count >= 128)
+ n = 128;
+ else
+ n = count;
+
+ if (storage_write_sectors(sector,n,sectorbuf) < 0) {
+ printf("[ERR] Write failed in zero_sectors\n");
+ return -1;
+ }
+ sector += n;
+ count -= n;
+ }
+
+ return 0;
+}
+
+
+/*
+28.2 CALCULATING THE VOLUME SERIAL NUMBER
+
+For example, say a disk was formatted on 26 Dec 95 at 9:55 PM and 41.94
+seconds. DOS takes the date and time just before it writes it to the
+disk.
+
+Low order word is calculated: Volume Serial Number is:
+ Month & Day 12/26 0c1ah
+ Sec & Hundrenths 41:94 295eh 3578:1d02
+ -----
+ 3578h
+
+High order word is calculated:
+ Hours & Minutes 21:55 1537h
+ Year 1995 07cbh
+ -----
+ 1d02h
+*/
+static uint32_t get_volume_id ( void )
+{
+ /* TODO */
+#if 0
+ SYSTEMTIME s;
+ uint32_t d;
+ uint16_t lo,hi,tmp;
+
+ GetLocalTime( &s );
+
+ lo = s.wDay + ( s.wMonth << 8 );
+ tmp = (s.wMilliseconds/10) + (s.wSecond << 8 );
+ lo += tmp;
+
+ hi = s.wMinute + ( s.wHour << 8 );
+ hi += s.wYear;
+
+ d = lo + (hi << 16);
+ return(d);
+#endif
+ return(0);
+}
+
+/*
+This is the Microsoft calculation from FATGEN
+
+ uint32_t RootDirSectors = 0;
+ uint32_t TmpVal1, TmpVal2, FATSz;
+
+ TmpVal1 = DskSize - ( ReservedSecCnt + RootDirSectors);
+ TmpVal2 = (256 * SecPerClus) + NumFATs;
+ TmpVal2 = TmpVal2 / 2;
+ FATSz = (TmpVal1 + (TmpVal2 - 1)) / TmpVal2;
+
+ return( FatSz );
+*/
+
+
+static uint32_t get_fat_size_sectors(uint32_t DskSize, uint32_t ReservedSecCnt,
+ uint32_t SecPerClus, uint32_t NumFATs,
+ uint32_t BytesPerSect)
+{
+ uint32_t Numerator, Denominator;
+ uint32_t FatElementSize = 4;
+ uint32_t FatSz;
+
+ /* This is based on
+ http://hjem.get2net.dk/rune_moeller_barnkob/filesystems/fat.html
+ I've made the obvious changes for FAT32
+ */
+
+ Numerator = FatElementSize * ( DskSize - ReservedSecCnt );
+ Denominator = ( SecPerClus * BytesPerSect ) + ( FatElementSize * NumFATs );
+ FatSz = Numerator / Denominator;
+
+ /* round up */
+ FatSz += 1;
+
+ return((uint32_t)FatSz);
+}
+
+static uint8_t get_spc(uint32_t ClusterSizeKB, uint32_t BytesPerSect)
+{
+ uint32_t spc = ( ClusterSizeKB * 1024 ) / BytesPerSect;
+ return( (uint8_t) spc );
+}
+
+static uint8_t get_sectors_per_cluster(uint32_t DiskSizeSectors,
+ uint32_t BytesPerSect)
+{
+ uint8_t ret = 0x01; /* 1 sector per cluster */
+ int32_t DiskSizeMB = DiskSizeSectors / ( 1024*1024 / SECTOR_SIZE);
+
+ /* 512 MB to 8,191 MB 4 KB */
+ if ( DiskSizeMB > 512 )
+ ret = get_spc( 4, BytesPerSect ); /* ret = 0x8; */
+
+ /* 8,192 MB to 16,383 MB 8 KB */
+ if ( DiskSizeMB > 8192 )
+ ret = get_spc( 8, BytesPerSect ); /* ret = 0x10; */
+
+ /* 16,384 MB to 32,767 MB 16 KB */
+ if ( DiskSizeMB > 16384 )
+ ret = get_spc( 16, BytesPerSect ); /* ret = 0x20; */
+
+ /* Larger than 32,768 MB 32 KB */
+ if ( DiskSizeMB > 32768 )
+ ret = get_spc( 32, BytesPerSect ); /* ret = 0x40; */
+
+ return( ret );
+
+}
+
+static void create_boot_sector(unsigned char* buf)
+{
+ struct FAT_BOOTSECTOR32* pFAT32BootSect = (struct FAT_BOOTSECTOR32*)buf;
+
+ /* fill out the boot sector and fs info */
+ pFAT32BootSect->sJmpBoot[0]=0xEB;
+ pFAT32BootSect->sJmpBoot[1]=0x5A;
+ pFAT32BootSect->sJmpBoot[2]=0x90;
+ memcpy(pFAT32BootSect->sOEMName, "MSWIN4.1", 8 );
+ pFAT32BootSect->wBytsPerSec = rb_htole16(BytesPerSect);
+ pFAT32BootSect->bSecPerClus = SectorsPerCluster ;
+ pFAT32BootSect->wRsvdSecCnt = rb_htole16(ReservedSectCount);
+ pFAT32BootSect->bNumFATs = NumFATs;
+ pFAT32BootSect->wRootEntCnt = rb_htole16(0);
+ pFAT32BootSect->wTotSec16 = rb_htole16(0);
+ pFAT32BootSect->bMedia = 0xF8;
+ pFAT32BootSect->wFATSz16 = rb_htole16(0);
+ pFAT32BootSect->wSecPerTrk = 63;
+ pFAT32BootSect->wNumHeads = 255;
+ pFAT32BootSect->dHiddSec = 0;
+ pFAT32BootSect->dTotSec32 = rb_htole32(TotalSectors);
+ pFAT32BootSect->dFATSz32 = rb_htole32(FatSize);
+ pFAT32BootSect->wExtFlags = rb_htole16(0);
+ pFAT32BootSect->wFSVer = rb_htole16(0);
+ pFAT32BootSect->dRootClus = rb_htole32(2);
+ pFAT32BootSect->wFSInfo = rb_htole16(1);
+ pFAT32BootSect->wBkBootSec = rb_htole16(BackupBootSect);
+ pFAT32BootSect->bDrvNum = 0x80;
+ pFAT32BootSect->Reserved1 = 0;
+ pFAT32BootSect->bBootSig = 0x29;
+ pFAT32BootSect->dBS_VolID = rb_htole32(VolumeId);
+ memcpy(pFAT32BootSect->sVolLab, VolId, 11);
+ memcpy(pFAT32BootSect->sBS_FilSysType, "FAT32 ", 8 );
+
+ buf[510] = 0x55;
+ buf[511] = 0xaa;
+}
+
+static void create_fsinfo(unsigned char* buf)
+{
+ struct FAT_FSINFO* pFAT32FsInfo = (struct FAT_FSINFO*)buf;
+
+ /* FSInfo sect */
+ pFAT32FsInfo->dLeadSig = rb_htole32(0x41615252);
+ pFAT32FsInfo->dStrucSig = rb_htole32(0x61417272);
+ pFAT32FsInfo->dFree_Count = rb_htole32((uint32_t) -1);
+ pFAT32FsInfo->dNxt_Free = rb_htole32((uint32_t) -1);
+ pFAT32FsInfo->dTrailSig = rb_htole32(0xaa550000);
+ pFAT32FsInfo->dFree_Count = rb_htole32((UserAreaSize/SectorsPerCluster)-1);
+
+ /* clusters 0-1 reserved, we used cluster 2 for the root dir */
+ pFAT32FsInfo->dNxt_Free = rb_htole32(3);
+}
+
+static void create_firstfatsector(unsigned char* buf)
+{
+ uint32_t* p = (uint32_t*)buf; /* We know the buffer is aligned */
+
+ /* First FAT Sector */
+ p[0] = rb_htole32(0x0ffffff8); /* Reserved cluster 1 media id in low byte */
+ p[1] = rb_htole32(0x0fffffff); /* Reserved cluster 2 EOC */
+ p[2] = rb_htole32(0x0fffffff); /* end of cluster chain for root dir */
+}
+
+int format_partition(int start, int size)
+{
+ uint32_t i;
+ uint32_t qTotalSectors=0;
+ uint32_t FatNeeded;
+
+ VolumeId = get_volume_id( );
+
+ /* Only support hard disks at the moment */
+ if ( SECTOR_SIZE != 512 )
+ {
+ printf("[ERR] Only disks with 512 bytes per sector are supported.\n");
+ return -1;
+ }
+ BytesPerSect = SECTOR_SIZE;
+
+ /* Checks on Disk Size */
+ qTotalSectors = size;
+
+ /* low end limit - 65536 sectors */
+ if ( qTotalSectors < 65536 )
+ {
+ /* I suspect that most FAT32 implementations would mount this
+ volume just fine, but the spec says that we shouldn't do
+ this, so we won't */
+
+ printf("[ERR] This drive is too small for FAT32 - there must be at least 64K clusters\n" );
+ return -1;
+ }
+
+ if ( qTotalSectors >= 0xffffffff )
+ {
+ /* This is a more fundamental limitation on FAT32 - the total
+ sector count in the root dir is 32bit. With a bit of
+ creativity, FAT32 could be extended to handle at least 2^28
+ clusters There would need to be an extra field in the
+ FSInfo sector, and the old sector count could be set to
+ 0xffffffff. This is non standard though, the Windows FAT
+ driver FASTFAT.SYS won't understand this. Perhaps a future
+ version of FAT32 and FASTFAT will handle this. */
+
+ printf("[ERR] This drive is too big for FAT32 - max 2TB supported\n");
+ }
+
+ if ( sectors_per_cluster ) {
+ SectorsPerCluster = sectors_per_cluster;
+ } else {
+ SectorsPerCluster = get_sectors_per_cluster(size,
+ BytesPerSect );
+ }
+
+ TotalSectors = (uint32_t) qTotalSectors;
+
+ FatSize = get_fat_size_sectors(TotalSectors, ReservedSectCount,
+ SectorsPerCluster, NumFATs, BytesPerSect );
+
+ UserAreaSize = TotalSectors - ReservedSectCount - (NumFATs*FatSize);
+
+ /* First zero out ReservedSect + FatSize * NumFats + SectorsPerCluster */
+ SystemAreaSize = (ReservedSectCount+(NumFATs*FatSize) + SectorsPerCluster);
+
+ /* Work out the Cluster count */
+ FatNeeded = UserAreaSize/SectorsPerCluster;
+
+ /* check for a cluster count of >2^28, since the upper 4 bits of
+ the cluster values in the FAT are reserved. */
+ if (FatNeeded > 0x0FFFFFFF) {
+ printf("[ERR] This drive has more than 2^28 clusters, try to specify a larger cluster size\n" );
+ return -1;
+ }
+
+ /* Sanity check, make sure the fat is big enough.
+ Convert the cluster count into a Fat sector count, and check
+ the fat size value we calculated earlier is OK. */
+
+ FatNeeded *=4;
+ FatNeeded += (BytesPerSect-1);
+ FatNeeded /= BytesPerSect;
+
+ if ( FatNeeded > FatSize ) {
+ printf("[ERR] Drive too big to format\n");
+ return -1;
+ }
+
+ /*
+ Write boot sector, fats
+ Sector 0 Boot Sector
+ Sector 1 FSInfo
+ Sector 2 More boot code - we write zeros here
+ Sector 3 unused
+ Sector 4 unused
+ Sector 5 unused
+ Sector 6 Backup boot sector
+ Sector 7 Backup FSInfo sector
+ Sector 8 Backup 'more boot code'
+ zero'd sectors upto ReservedSectCount
+ FAT1 ReservedSectCount to ReservedSectCount + FatSize
+ ...
+ FATn ReservedSectCount to ReservedSectCount + FatSize
+ RootDir - allocated to cluster2
+ */
+
+
+ printf("[INFO] Formatting partition:...");
+
+ /* Once zero_sectors has run, any data on the drive is basically lost... */
+ printf("[INFO] Clearing out %d sectors for Reserved sectors, fats and root cluster...\n", SystemAreaSize );
+
+ zero_sectors(start, SystemAreaSize);
+
+ printf("[INFO] Initialising reserved sectors and FATs...\n" );
+
+ /* Create the boot sector structure */
+ create_boot_sector(sectorbuf);
+ create_fsinfo(sectorbuf + 512);
+
+ if (storage_write_sectors(start,2,sectorbuf)) {
+ printf("[ERR] Write failed (first copy of bootsect/fsinfo)\n");
+ return -1;
+ }
+
+ if (storage_write_sectors(start + BackupBootSect,2,sectorbuf)) {
+ printf("[ERR] Write failed (first copy of bootsect/fsinfo)\n");
+ return -1;
+ }
+
+ /* Create the first FAT sector */
+ create_firstfatsector(sectorbuf);
+
+ /* Write the first fat sector in the right places */
+ for ( i=0; i<NumFATs; i++ ) {
+ int SectorStart = ReservedSectCount + (i * FatSize );
+
+ if (storage_write_sectors(start + SectorStart,1,sectorbuf)) {
+ printf("[ERR] Write failed (first copy of bootsect/fsinfo)\n");
+ return -1;
+ }
+ }
+
+ printf("[INFO] Format successful\n");
+
+ return 0;
+}