XMM6180

This is the baseband platform used in the iPhone 4 and iPad 2 (GSM). It is produced by Infineon and is marketed as the X-Gold 618.

The firmware is based on ThreadX, a realtime OS.

Firmware files are signed for a specific device by Apple during the restore process. As a result, the baseband will allow downgrades provided that Apple is still signing the firmware.

== Main Features (according to Datasheet) ==

Modem

 * HSDPA/HSUPA 7.2Mbps/2.9Mbps (Apple confirmed upload was 5.8Mbps)
 * WCDMA: 384kbps DL/UL
 * EDGE up to MSC33 with SAIC
 * Speech: NB-AMR, WB-AMR

CPU

 * ARM1176 @ 416MHz

Memory

 * LPDDR1-SDRAM
 * NOR & NAND Flash
 * eSD/eMMC

Connectivity and Interfaces

 * Digital RF interface V3.09
 * High speed SIM card interface
 * USB 2.0 HS
 * 3 x USIF; 2xI2S; 2xI2C
 * 3 x SD/MMC card interface

Memory Map
Although the crash dump would seem to contradict this, code running from 0x60xxxxxx
 * 0x40FE0000-0x41000000 -- Bootloader(0x2)
 * 0x40040000-0x40800000 -- Main Code(0x4)
 * 0x40800000-0x41000000 -- AENEAS(0x5)
 * 0x60000000-0x60200000 -- EBL(0x3)
 * 0x00080000-0x00A00000 -- PSI_RAM(0x1)
 * 0x40800000-0x40A00000 -- CDS(0x4)

Flash Files in 01.59.00

 * psi_ram.fls
 * RAM bootloader?
 * 0x80000 size 0xFF00
 * psi_flash.fls
 * Flash bootloader
 * 0x40FE0000 size 0x8000
 * stack.fls(ICE3.fls)
 * Main baseband code
 * 0x40040000 size 0x6F7E5C
 * start vector @ 0x40040408
 * ebl.fls
 * Flashing loader??
 * 0x60000000 size 0xDFB0

iPhone 4 (GSM) and iPad 2 (GSM)
The first iPad 2s were delivered with iOS 4.3, so the oldest possible baseband would be 4.10.01 for this device. 01.59.00   4.0     (Build 8A293) 4.0.1  (Build 8A306) 4.0.2  (Build 8A400) 02.07.01   4.1b1   (Build 8B5080c) 02.??.??   4.1b2   (Build 8B5091b) 02.10.04   4.1     (Build 8B117) 03.08.00   4.2b1   (Build 8C5091e) 03.09.00   4.2b2   (Build 8C5101c) 03.10.01   4.2b3   (Build 8C5115c) 4.2GM  (Build 8C134) 4.2.1GM (Build 8C148) 4.2.1  (Build 8C148) 04.08.00   4.3b    (Build 8F5132f) 4.3b1  (Build 8F5148b) 04.09.00   4.3b2   (Build 8F5153d) 04.10.01   4.3b3   (Build 8F5166b) 4.3GM  (Build 8F190) 4.3    (Build 8F190) 4.3    (Build 8F191) 4.3.1  (Build 8G4) 4.3.2  (Build 8H7) 4.3.3  (Build 8J2) 4.3.4  (Build 8K2) 4.3.5  (Build 8L1) 04.11.04   5.0b1   (Build 9A5220p) 04.11.06   5.0b2   (Build 9A5248d) 5.0b3  (Build 9A5259f) 5.0b4  (Build 9A5274d) 04.11.07   5.0b5   (Build 9A5288d) 04.11.08   5.0b6   (Build 9A5302b) 5.0b7  (Build 9A5313e) 5.0GM  (Build 9A334) 5.0.1b1 (Build 9A402) 5.0.1b2 (Build 9A404) 5.0.1  (Build 9A405) 5.1b1  (Build 9B5117b) 5.1b2  (Build 9B5127c)