How to increase Max NAND partition number on MDM9x15?

This solution describes the method to increase the maximum number of NAND partition on 9x15. Current partition is limit to 16 maximum, following changes will increase it to 22.

============================
Changes
============================

Boot loader:

1) boot_images\core\boot\secboot3\src\miparti.h: change following define to new max partition number, e.g.

#define FLASH_NUM_PART_ENTRIES 22

2) boot_images\core\boot\secboot3\src\mibib.h: change following define to new max partition number, make sure the value of MIBIB_DEFAULT_PARTI_SIZE is the same of FLASH_NUM_PART_ENTRIES, e.g.

#define MIBIB_DEFAULT_PARTI_SIZE 0x16

3) common\build\partition_nand_9x15.xml (old build: boot_images\core\storage\tools\nandbootmbn\ partition_nand_9x15.xml): insert new partitions, like this

<partition>
<name length="16" type="string">0:FAKE9</name>
<size_blks length="4">0x6</size_blks>
<pad_blks length="4">0x4</pad_blks>
<which_flash>0</which_flash>
<attr>0xFF</attr>
<attr>0xFF</attr>
<attr>0x00</attr>
<attr>0xFF</attr>
</partition>

Accordingly, recount the sequence of "system" partition, for example, if the original sequence of "system" partition is 8 (starting from MIBIB as 0), after the above "FAKE9" partition is inserted, the new sequence of "system" partition becomes 9, which will be used to change 9615-cdp-bootimg.inc later.

LK:

1) apps_proc\bootable\bootloader\lk\platform\msm_shared\smem_ptable.c: add a define for the new max partition number, e.g.

#define FLASH_NUM_PART_ENTRIES_SMEM 22

Then use FLASH_NUM_PART_ENTRIES_SMEM in following structure, e.g.


struct smem_ptable {
#define _SMEM_PTABLE_MAGIC_1 0x55ee73aa
#define _SMEM_PTABLE_MAGIC_2 0xe35ebddb
unsigned magic[2];
unsigned version;
unsigned len;
struct smem_ptn parts[FLASH_NUM_PART_ENTRIES_SMEM];
} __attribute__ ((__packed__));


Also use FLASH_NUM_PART_ENTRIES_SMEM in the for loop in the following functions:

static void dump_smem_ptable(void)
{
…
for (i = 0; i < FLASH_NUM_PART_ENTRIES_SMEM; i++) {
struct smem_ptn *p = &smem_ptable.parts[i];
if (p->name[0] == '\0')
continue;
…
}
}


void smem_add_modem_partitions(struct ptable *flash_ptable)
{
…
for (i = 0; i < FLASH_NUM_PART_ENTRIES_SMEM; i++) {
char *token;
char *pname = NULL;
struct smem_ptn *p = &smem_ptable.parts[i];
if (p->name[0] == '\0')
continue;
token = strtok(p->name, ":");
…
}
}


LE:

1) apps_proc\kernel\arch\arm\mach-msm\nand_partition.c: change following define to new max partition number, e.g.

#define MSM_MAX_PARTITIONS 22

2) apps_proc\build\recipes\recipes\images\9615-cdp-bootimg.inc (old build: make_bbimg.sh): in the following command line, change argumentroot=/dev/mtdblockXX, where XX is the new partition number for the "system" partition counted earlier in partition_nand_9x15.xml, e.g. XX=20

--cmdline "noinitrd root=/dev/mtdblock20 rw rootfstype=yaffs2 console=ttyHSL0,115200,n8 no_console_suspend=1 androidboot.hardware=qcom" \


============================
Build
============================

After above changes, compile boot loaders to generate new boot loaders, nand_tools; also make a clean APPS build on Linux to generate new LK and LE images.


============================
Verification
============================

1) Use HEX viewer to open partition.mbn, look for the newly added partitions.

2) Use HEX viewer to open boot-oe-msm9615.img, look for theroot=/dev/mtdblockXX

3) Use T32 to flash non-HLOS images, this will verify nand_tools is working fine with new max partition change

4) Use fastboot, flash APSS and boot images. Reboot to HLOS, and collect kernel log, look for the following messages:


[ 2.543934] yaffs: Attempting MTD mount of 31.20,"mtdblock20"
[ 4.802777] yaffs: yaffs_read_super: is_checkpointed 0
[ 4.802899] VFS: Mounted root (yaffs2 filesystem) on device 31:20.



This will verity Linux File System is still mounted correctly.