mirror of
https://github.com/u-boot/u-boot.git
synced 2024-11-25 13:14:19 +08:00
626365b4f7
Now that it is possible to load SPL and u-boot.img via imx_usb_loader tool, mention this method instead of the old one that relied on ymodem. Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
164 lines
5.0 KiB
Plaintext
164 lines
5.0 KiB
Plaintext
U-Boot for Freescale i.MX6
|
|
|
|
This file contains information for the port of U-Boot to the Freescale i.MX6
|
|
SoC.
|
|
|
|
1. CONVENTIONS FOR FUSE ASSIGNMENTS
|
|
-----------------------------------
|
|
|
|
1.1 MAC Address: It is stored in fuse bank 4, with the 32 lsbs in word 2 and the
|
|
16 msbs in word 3[15:0].
|
|
For i.MX6SX and i.MX6UL, they have two MAC addresses. The second MAC address
|
|
is stored in fuse bank 4, with the 16 lsb in word 3[31:16] and the 32 msbs in
|
|
word 4.
|
|
|
|
Example:
|
|
|
|
For reading the MAC address fuses on a MX6Q:
|
|
|
|
- The MAC address is stored in two fuse addresses (the fuse addresses are
|
|
described in the Fusemap Descriptions table from the mx6q Reference Manual):
|
|
|
|
0x620[31:0] - MAC_ADDR[31:0]
|
|
0x630[15:0] - MAC_ADDR[47:32]
|
|
|
|
In order to use the fuse API, we need to pass the bank and word values, which
|
|
are calculated as below:
|
|
|
|
Fuse address for the lower MAC address: 0x620
|
|
Base address for the fuses: 0x400
|
|
|
|
(0x620 - 0x400)/0x10 = 0x22 = 34 decimal
|
|
|
|
As the fuses are arranged in banks of 8 words:
|
|
|
|
34 / 8 = 4 and the remainder is 2, so in this case:
|
|
|
|
bank = 4
|
|
word = 2
|
|
|
|
And the U-Boot command would be:
|
|
|
|
=> fuse read 4 2
|
|
Reading bank 4:
|
|
|
|
Word 0x00000002: 9f027772
|
|
|
|
Doing the same for the upper MAC address:
|
|
|
|
Fuse address for the upper MAC address: 0x630
|
|
Base address for the fuses: 0x400
|
|
|
|
(0x630 - 0x400)/0x10 = 0x23 = 35 decimal
|
|
|
|
As the fuses are arranged in banks of 8 words:
|
|
|
|
35 / 8 = 4 and the remainder is 3, so in this case:
|
|
|
|
bank = 4
|
|
word = 3
|
|
|
|
And the U-Boot command would be:
|
|
|
|
=> fuse read 4 3
|
|
Reading bank 4:
|
|
|
|
Word 0x00000003: 00000004
|
|
|
|
,which matches the ethaddr value:
|
|
=> echo ${ethaddr}
|
|
00:04:9f:02:77:72
|
|
|
|
Some other useful hints:
|
|
|
|
- The 'bank' and 'word' numbers can be easily obtained from the mx6 Reference
|
|
Manual. For the mx6quad case, please check the "46.5 OCOTP Memory Map/Register
|
|
Definition" from the "i.MX 6Dual/6Quad Applications Processor Reference Manual,
|
|
Rev. 1, 04/2013" document. For example, for the MAC fuses we have:
|
|
|
|
Address:
|
|
21B_C620 Value of OTP Bank4 Word2 (MAC Address)(OCOTP_MAC0)
|
|
|
|
21B_C630 Value of OTP Bank4 Word3 (MAC Address)(OCOTP_MAC1)
|
|
|
|
- The command '=> fuse read 4 2 2' reads the whole MAC addresses at once:
|
|
|
|
=> fuse read 4 2 2
|
|
Reading bank 4:
|
|
|
|
Word 0x00000002: 9f027772 00000004
|
|
|
|
2. Using imx_usb_loader for first install with SPL
|
|
--------------------------------------------------
|
|
|
|
imx_usb_loader is a very nice tool by Boundary Devices that
|
|
allow to install U-Boot without a JTAG debugger, using
|
|
the USB boot mode as described in the manual. It is
|
|
a replacement for Freescale's MFGTOOLS.
|
|
|
|
The sources can be found here:
|
|
|
|
https://github.com/boundarydevices/imx_usb_loader.git
|
|
|
|
Booting in USB mode, the i.MX6 announces itself to the Linux Host as:
|
|
|
|
Bus 001 Device 111: ID 15a2:0061 Freescale Semiconductor, Inc.
|
|
|
|
imx_usb_loader is able to download a single file (u-boot.imx)
|
|
to the board. For boards without SPL support, it is enough to
|
|
issue the command:
|
|
|
|
sudo ../imx_usb_loader/imx_usb -v u-boot.imx
|
|
|
|
In order to load SPL and u-boot.img via imx_usb_loader tool,
|
|
please refer to doc/README.sdp.
|
|
|
|
3. Using Secure Boot on i.MX6 machines with SPL support
|
|
-------------------------------------------------------
|
|
|
|
This version of U-Boot is able to build a signable version of the SPL
|
|
as well as a signable version of the U-Boot image. The signature can
|
|
be verified through High Assurance Boot (HAB).
|
|
|
|
CONFIG_SECURE_BOOT is needed to build those two binaries.
|
|
After building, you need to create a command sequence file and use
|
|
Freescales Code Signing Tool to sign both binaries. After creation,
|
|
the mkimage tool outputs the required information about the HAB Blocks
|
|
parameter for the CSF. During the build, the information is preserved
|
|
in log files named as the binaries. (SPL.log and u-boot-ivt.log).
|
|
|
|
More information about the CSF and HAB can be found in the AN4581.
|
|
https://cache.freescale.com/files/32bit/doc/app_note/AN4581.pdf
|
|
|
|
We don't want to explain how to create a PKI tree or SRK table as
|
|
this is well explained in the Application Note.
|
|
|
|
Example Output of the SPL (imximage) creation:
|
|
Image Type: Freescale IMX Boot Image
|
|
Image Ver: 2 (i.MX53/6/7 compatible)
|
|
Mode: DCD
|
|
Data Size: 61440 Bytes = 60.00 kB = 0.06 MB
|
|
Load Address: 00907420
|
|
Entry Point: 00908000
|
|
HAB Blocks: 00907400 00000000 0000cc00
|
|
|
|
Example Output of the u-boot-ivt.img (firmware_ivt) creation:
|
|
Image Name: U-Boot 2016.11-rc1-31589-g2a4411
|
|
Created: Sat Nov 5 21:53:28 2016
|
|
Image Type: ARM U-Boot Firmware with HABv4 IVT (uncompressed)
|
|
Data Size: 352192 Bytes = 343.94 kB = 0.34 MB
|
|
Load Address: 17800000
|
|
Entry Point: 00000000
|
|
HAB Blocks: 0x177fffc0 0x0000 0x00054020
|
|
|
|
The CST (Code Signing Tool) can be downloaded from NXP.
|
|
# Compile CSF and create signature
|
|
./cst --o csf-u-boot.bin < command_sequence_uboot.csf
|
|
./cst --o csf-SPL.bin < command_sequence_spl.csf
|
|
# Append compiled CSF to Binary
|
|
cat SPL csf-SPL.bin > SPL-signed
|
|
cat u-boot-ivt.img csf-u-boot.bin > u-boot-signed.img
|
|
|
|
These two signed binaries can be used on an i.MX6 in closed
|
|
configuration when the according SRK Table Hash has been flashed.
|