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Linksys EA9500 Flash Layout

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From three sources i.e CFE, boot log and Linksys diagnostics obtained from stock firmware it is difficult to clearly guess the partitions in EA9500.

From what we know, the flash is a Toshiba 128MB (TC58BVG0S3HTA00)

CFE log:

CFE> show devices
Device Name          Description
-------------------  ---------------------------------------------------------
uart0                NS16550 UART at 0x18000300
uart1                NS16550 UART at 0x18000400
nflash0              Toshiba NAND flash size 131072KB
nflash0.boot         Toshiba NAND flash offset 0 size 512KB
nflash0.nvram        Toshiba NAND flash offset 80000 size 1024KB
nflash0.devinfo      Toshiba NAND flash offset 180000 size 512KB
nflash0.trx          Toshiba NAND flash offset 200000 size 1KB
nflash0.os           Toshiba NAND flash offset 20001C size 29696KB
nflash0.trx2         Toshiba NAND flash offset 1F00000 size 1KB
nflash0.os2          Toshiba NAND flash offset 1F0001C size 29696KB
nflash1.boot         Toshiba NAND flash offset 0 size 512KB
nflash1.nvram        Toshiba NAND flash offset 80000 size 1024KB
nflash1.devinfo      Toshiba NAND flash offset 180000 size 512KB
nflash1.trx          Toshiba NAND flash offset 200000 size 29696KB
nflash1.trx2         Toshiba NAND flash offset 1F00000 size 29696KB
nflash1.brcmnand     Toshiba NAND flash offset 3C00000 size 69632KB
eth0                 Broadcom BCM47XX 10/100/1000 Mbps Ethernet Controller

 

 

Boot Log:

Creating 6 MTD partitions on "nflash":
0x000000000000-0x000000080000 : "boot" 
0x000000080000-0x000000200000 : "nvram" 
0x000000200000-0x000001f00000 : "linux" 
0x00000042db00-0x000001f00000 : "rootfs" 
0x000001f00000-0x000005200000 : "linux2" 
0x00000212dba4-0x000005200000 : "rootfs2"
...
Creating 1 MTD partitions on "brcmnand":
0x000005200000-0x000008000000 : "brcmnand"

 

 

Linksys Diagnostics:

cat /proc/mtd:
 dev:  size     erasesize name
 mtd0: 00080000 00020000  "boot"
 mtd1: 00180000 00020000  "nvram"
 mtd2: 01d00000 00020000  "linux"
 mtd3: 01ad2504 00020000  "rootfs"
 mtd4: 03300000 00020000  "linux2"
 mtd5: 030d245c 00020000  "rootfs2"
 mtd6: 02e00000 00020000  "brcmnand"

 

Visually –

ea9500-partitions-observed

Combining all three sets we can deduce following:

ea9500-partitions

*mtd4, mtd5, mtd6 are safe estimates.

In order to support the layout in OpenWrt or Lede, we have to ensure that the
firmware image is less than 29MB

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Written by Vivek Unune

February 6, 2017 at 8:17 pm

Posted in lede, linux, openwrt

Tagged with , , , , , ,