In preparation for use with sansapatcher, change portalplayer bootloaders to read firmwares in mi4 format.

When loading the OF:
1) first try to load from a hidden disk partition
2) try loading /System/OF.mi4
3) finally fall back to loading /System/OF.bin which is what the old bootloader used.


git-svn-id: svn://svn.rockbox.org/rockbox/trunk@12802 a1c6a512-1295-4272-9138-f99709370657

bootloader/main-pp.c

@@ -29,6 +29,80 @@
 #include "ata.h"
 #include "button.h"
 #include "disk.h"
+#include <string.h>
+
+/*
+ * CRC32 implementation taken from:
+ *
+ * efone - Distributed internet phone system.
+ *
+ * (c) 1999,2000 Krzysztof Dabrowski
+ * (c) 1999,2000 ElysiuM deeZine
+ *
+ * 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.
+ *
+ */
+
+/* based on implementation by Finn Yannick Jacobs */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+/* crc_tab[] -- this crcTable is being build by chksum_crc32GenTab().
+ *		so make sure, you call it before using the other
+ *		functions!
+ */
+static unsigned int crc_tab[256];
+
+/* chksum_crc() -- to a given block, this one calculates the
+ *				crc32-checksum until the length is
+ *				reached. the crc32-checksum will be
+ *				the result.
+ */
+unsigned int chksum_crc32 (unsigned char *block, unsigned int length)
+{
+   register unsigned long crc;
+   unsigned long i;
+
+   crc = 0;
+   for (i = 0; i < length; i++)
+   {
+      crc = ((crc >> 8) & 0x00FFFFFF) ^ crc_tab[(crc ^ *block++) & 0xFF];
+   }
+   return (crc);
+}
+
+/* chksum_crc32gentab() --      to a global crc_tab[256], this one will
+ *				calculate the crcTable for crc32-checksums.
+ *				it is generated to the polynom [..]
+ */
+
+static void chksum_crc32gentab (void)
+{
+   unsigned long crc, poly;
+   int i, j;
+
+   poly = 0xEDB88320L;
+   for (i = 0; i < 256; i++)
+   {
+      crc = i;
+      for (j = 8; j > 0; j--)
+      {
+	 if (crc & 1)
+	 {
+	    crc = (crc >> 1) ^ poly;
+	 }
+	 else
+	 {
+	    crc >>= 1;
+	 }
+      }
+      crc_tab[i] = crc;
+   }
+}
 
 /* Button definitions */
 #if CONFIG_KEYPAD == IRIVER_H10_PAD
@@ -50,21 +124,167 @@ unsigned char *loadbuffer = (unsigned char *)DRAM_START;
 /* Bootloader version */
 char version[] = APPSVERSION;
 
+/* Locations and sizes in hidden partition on Sansa */
+#define PPMI_OFFSET         1024
+#define PPMI_SIZE           1
+#define MI4_HEADER_SIZE     1
+
+/* mi4 header structure */
+struct mi4header_t {
+    unsigned char magic[4];
+    uint32_t version;
+    uint32_t length;
+    uint32_t crc32;
+    uint32_t enctype;
+    uint32_t mi4size;
+    uint32_t plaintext;
+    uint32_t dsa_key[10];
+    uint32_t pad[109];
+    unsigned char type[4];
+    unsigned char model[4];
+};
+
+/* PPMI header structure */
+struct ppmi_header_t {
+    unsigned char magic[4];
+    uint32_t length;
+    uint32_t pad[126];
+};
+
+/* Load mi4 format firmware image */
+int load_mi4(unsigned char* buf, char* firmware, unsigned int buffer_size)
+{
+    int fd;
+    struct mi4header_t mi4header;
+    int rc;
+    unsigned long sum;
+    char filename[MAX_PATH];
+
+    snprintf(filename,sizeof(filename),"/.rockbox/%s",firmware);
+    fd = open(filename, O_RDONLY);
+    if(fd < 0)
+    {
+        snprintf(filename,sizeof(filename),"/%s",firmware);
+        fd = open(filename, O_RDONLY);
+        if(fd < 0)
+            return EFILE_NOT_FOUND;
+    }
+
+    read(fd, &mi4header, 0x200);
+
+    /* We don't support encrypted mi4 files yet */
+    if( (mi4header.plaintext + 0x200) != mi4header.mi4size)
+        return EINVALID_FORMAT;
+
+    /* MI4 file size */
+    printf("mi4 size: %x", mi4header.length);
+
+    if (mi4header.length > buffer_size)
+        return EFILE_TOO_BIG;
+
+    /* CRC32 */
+    printf("CRC32: %x", mi4header.crc32);
+
+    /* Rockbox model id */
+    printf("Model id: %4s", mi4header.model);
+
+    /* Read binary type (RBOS, RBBL) */
+    printf("Binary type: %4s", mi4header.type);
+
+    /* Load firmware */
+    lseek(fd, FIRMWARE_OFFSET_FILE_DATA, SEEK_SET);
+    rc = read(fd, buf, mi4header.mi4size-0x200);
+    if(rc < (int)mi4header.mi4size-0x200)
+        return EREAD_IMAGE_FAILED;
+
+    /* Check CRC32 to see if we have a valid file */
+    sum = chksum_crc32 (buf,mi4header.mi4size-0x200);
+
+    printf("Calculated CRC32: %x", sum);
+
+    if(sum != mi4header.crc32)
+        return EBAD_CHKSUM;
+    
+    return EOK;
+}
+
+/* Load mi4 firmware from a hidden disk partition */
+int load_mi4_part(unsigned char* buf, struct partinfo* pinfo, unsigned int buffer_size)
+{
+    struct mi4header_t mi4header;
+    struct ppmi_header_t ppmi_header;
+    unsigned long sum;
+    
+    /* Read header to find out how long the mi4 file is. */
+    ata_read_sectors(pinfo->start + PPMI_OFFSET, PPMI_SIZE, &ppmi_header);
+    
+    /* The first four characters at 0x80000 (sector 1024) should be PPMI*/
+    if( memcmp(ppmi_header.magic, "PPMI", 4) )
+        return EFILE_NOT_FOUND;
+    
+    printf("BL mi4 size: %x", ppmi_header.length);
+    
+    /* Read mi4 header of the OF */
+    ata_read_sectors(pinfo->start + PPMI_OFFSET + PPMI_SIZE 
+                       + (ppmi_header.length/512), MI4_HEADER_SIZE, &mi4header);
+    
+    /* We don't support encrypted mi4 files yet */
+    if( (mi4header.plaintext + 0x200) != mi4header.mi4size)
+        return EINVALID_FORMAT;
+
+    /* MI4 file size */
+    printf("OF mi4 size: %x", mi4header.length);
+
+    if (mi4header.length > buffer_size)
+        return EFILE_TOO_BIG;
+
+    /* CRC32 */
+    printf("CRC32: %x", mi4header.crc32);
+
+    /* Rockbox model id */
+    printf("Model id: %4s", mi4header.model);
+
+    /* Read binary type (RBOS, RBBL) */
+    printf("Binary type: %4s", mi4header.type);
+
+    /* Load firmware */
+    ata_read_sectors(pinfo->start + PPMI_OFFSET + PPMI_SIZE
+                        + (ppmi_header.length/512) + MI4_HEADER_SIZE,
+                        (mi4header.length-0x200)/512, buf);
+
+    /* Check CRC32 to see if we have a valid file */
+    sum = chksum_crc32 (buf,mi4header.mi4size-0x200);
+
+    printf("Calculated CRC32: %x", sum);
+
+    if(sum != mi4header.crc32)
+        return EBAD_CHKSUM;
+    
+    return EOK;
+}
+
 void* main(void)
 {
     char buf[256];
     int i;
     int btn;
     int rc;
+    int num_partitions;
     unsigned short* identify_info;
     struct partinfo* pinfo;
 
+    chksum_crc32gentab ();
+
     system_init();
     kernel_init();
     lcd_init();
     font_init();
     button_init();
 
+    lcd_set_foreground(LCD_WHITE);
+    lcd_set_background(LCD_BLACK);
+    lcd_clear_display();
+    
     btn = button_read_device();
 
     /* Enable bootloader messages */
@@ -94,31 +314,69 @@ void* main(void)
     }
 
     disk_init();
-    rc = disk_mount_all();
-    if (rc<=0)
+    num_partitions = disk_mount_all();
+    if (num_partitions<=0)
     {
-        error(EDISK,rc);
+        error(EDISK,num_partitions);
     }
 
-    pinfo = disk_partinfo(0);
-    printf("Partition 0: 0x%02x %ld MB", pinfo->type, pinfo->size / 2048);
+    /* Just list the first 2 partitions since we don't have any devices yet 
+       that have more than that */
+    for(i=0; i<2; i++)
+    {
+        pinfo = disk_partinfo(i);
+        printf("Partition %d: 0x%02x %ld MB",
+                i, pinfo->type, pinfo->size / 2048);
+    }
 
     if(btn & BOOTLOADER_BOOT_OF)
     {
-        /* Load original mi4 firmware. This expects a file called 
-           "/System/OF.bin" on the player. It should be a mi4 firmware decrypted 
-           and header stripped using mi4code. It reads the file in to a memory
-           buffer called loadbuffer. The rest of the loading is done in crt0.S
+        /* Load original mi4 firmware in to a memory buffer called loadbuffer.
+           The rest of the loading is done in crt0.S.
+           1) First try reading from the hidden partition (on Sansa only).
+           2) Next try a decrypted mi4 file in /System/OF.mi4
+           3) Finally, try a raw firmware binary in /System/OF.mi4. It should be
+              a mi4 firmware decrypted and header stripped using mi4code.
         */
         printf("Loading original firmware...");
+        
+        /* First try a hidden partition */
+        printf("Trying hidden partition");
+        pinfo = disk_partinfo(1);
+        if(pinfo->type == PARTITION_TYPE_HIDDEN)
+        {
+            rc = load_mi4_part(loadbuffer, pinfo, MAX_LOADSIZE);
+            if (rc < EOK) {
+                printf("Can't load from partition");
+                printf(strerror(rc));
+            } else {
+                return (void*)loadbuffer;
+            }
+        } else {
+            printf("No hidden partition found.");
+        }
+
+        printf("Trying /System/OF.mi4");
+        rc=load_mi4(loadbuffer, "/System/OF.mi4", MAX_LOADSIZE);
+        if (rc < EOK) {
+            printf("Can't load /System/OF.mi4");
+            printf(strerror(rc));
+        } else {
+            return (void*)loadbuffer;
+        }
+
+        printf("Trying /System/OF.bin");
         rc=load_raw_firmware(loadbuffer, "/System/OF.bin", MAX_LOADSIZE);
         if (rc < EOK) {
             printf("Can't load /System/OF.bin");
-            error(EBOOTFILE, rc);
+            printf(strerror(rc));
+        } else {
+            return (void*)loadbuffer;
         }
+
     } else {
         printf("Loading Rockbox...");
-        rc=load_firmware(loadbuffer, BOOTFILE, MAX_LOADSIZE);
+        rc=load_mi4(loadbuffer, BOOTFILE, MAX_LOADSIZE);
         if (rc < EOK) {
             printf("Can't load %s:", BOOTFILE);
             error(EBOOTFILE, rc);