/*************************************************************************** * __________ __ ___. * Open \______ \ ____ ____ | | _\_ |__ _______ ___ * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ * \/ \/ \/ \/ \/ * $Id$ * * Copyright (C) 2012 by Amaury Pouly * * 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 "partitions-imx233.h" #include "string.h" static bool enable_window = true; void imx233_partitions_enable_window(bool enable) { enable_window = enable; } bool imx233_partitions_is_window_enabled(void) { return enable_window; } #if (IMX233_PARTITIONS & IMX233_CREATIVE) #define MBLK_MAGIC 0x4d424c4b /* MBLK */ #define MBLK_COUNT 31 /* MBLK is not located in the first sector ! * Creative code uses the hard-coded *absolute* address 0x3ffe00, * bypassing all partition related information !! * NOTE: for some reason, the ZEN uses a different value ?! */ #ifdef CREATIVE_ZEN #define MBLK_ADDR 0x400000 #else #define MBLK_ADDR 0x3ffe00 #endif struct mblk_header_t { uint32_t magic; uint32_t block_size; uint64_t total_size; } __attribute__((packed)); struct mblk_partition_t { uint32_t size; uint32_t start; char name[8]; } __attribute__((packed)); static const char *creative_part_name(enum imx233_part_t part) { switch(part) { case IMX233_PART_CFS: return "cfs"; case IMX233_PART_MINIFS: return "minifs"; default: return ""; } } static int compute_window_creative(intptr_t user, part_read_fn_t read_fn, enum imx233_part_t part, unsigned *start, unsigned *end) { uint8_t mblk[512]; int ret = read_fn(user, MBLK_ADDR / 512, 1, mblk); if(ret < 0) return ret; struct mblk_header_t *hdr = (void *)mblk; if(hdr->magic != MBLK_MAGIC) return -70; /* bad magic */ struct mblk_partition_t *ent = (void *)(hdr + 1); const char *name = creative_part_name(part); for(int i = 0; i < MBLK_COUNT; i++) { if(ent[i].name[0] == 0) continue; if(strcmp(ent[i].name, name) == 0) { *start = ent[i].start * hdr->block_size / 512; if(part == IMX233_PART_CFS) { /* There is a bug in Creative's partitioner which restrict * computations to 32-bit even though the format itself can * handle much bigger volumes. We make the assumption * that the CFS partition always extends up the end of the * volume. So don't touch *end */ } else *end = *start + ent[i].size * hdr->block_size / 512; return 0; } } return -80; /* not found */ } #endif /* #(IMX233_PARTITIONS & IMX233_CREATIVE) */ #if (IMX233_PARTITIONS & IMX233_FREESCALE) static int compute_window_freescale(intptr_t user, part_read_fn_t read_fn, enum imx233_part_t part, unsigned *start, unsigned *end) { uint8_t mbr[512]; int ret = read_fn(user, 0, 1, mbr); if(ret < 0) return ret; /** * Freescale uses a strange layout: is has a first MBR at sector 0 with four entries: * 1) Actual user partition * 2) Sigmatel boot partition * 3)4) Other (certificate related ?) partitions * The partition 1) has type 1 but it's actually a type 5 (logical partition) with * a second partition table with usually one entry which is the FAT32 one. * The first table uses 512-byte sector size and the second one usually uses * 2048-byte logical sector size. * * We restrict the window to the user partition * * WARNING HACK FIXME BUG * Reverse engineering and experiments suggests that the OF ignores the lowest 2 bits * of the LBAs in the partition table. There is at least one example * (the Creative Zen X-Fi3) where this is important because the LBA of the user partition * is not a multiple of 4. The behaviour of the size field is less clear but * it seems that it is similarly truncated. */ if(mbr[510] != 0x55 || mbr[511] != 0xAA) return -101; /* invalid MBR */ if(part == IMX233_PART_DATA) { /* sanity check that the first partition is greater than 2Gib */ uint8_t *ent = &mbr[446]; *start = ent[8] | ent[9] << 8 | ent[10] << 16 | ent[11] << 24; /* ignore two lowest bits(see comment above) */ *start &= ~3; *end = (ent[12] | ent[13] << 8 | ent[14] << 16 | ent[15] << 24); *end &= ~3; /* ignore two lowest bits(order is important, first truncate then add start) */ *end += *start; if(ent[4] == 0x53) return -102; /* sigmatel partition */ if((*end - *start) < 4 * 1024 * 1024) return -103; /* partition too small */ return 0; } else if(part == IMX233_PART_BOOT) { /* sanity check that the second partition is correct */ uint8_t *ent = &mbr[462]; if(ent[4] != 0x53) return -104; /* wrong type */ *start = ent[8] | ent[9] << 8 | ent[10] << 16 | ent[11] << 24; *end = (ent[12] | ent[13] << 8 | ent[14] << 16 | ent[15] << 24); *end += *start; return 0; } else return -50; } #endif /* (IMX233_PARTITIONS & IMX233_FREESCALE) */ int imx233_partitions_compute_window(intptr_t user, part_read_fn_t read_fn, enum imx233_part_t part, unsigned *start, unsigned *end) { int ret = -1; #if (IMX233_PARTITIONS & IMX233_CREATIVE) ret = compute_window_creative(user, read_fn, part, start, end); if(ret >= 0) return ret; #endif #if (IMX233_PARTITIONS & IMX233_FREESCALE) ret = compute_window_freescale(user, read_fn, part, start, end); if(ret >= 0) return ret; #endif return ret; }