mirror of
				https://source.denx.de/u-boot/u-boot.git
				synced 2025-10-31 08:21:36 +01:00 
			
		
		
		
	Currently the High Assurance Boot procedure is documented in two places: - doc/README.imx6 - doc/README.mxc_hab It is better to consolidate all HAB related information into README.mxc_hab file, so move the content from README.imx6 to README.mxc_hab. Signed-off-by: Breno Lima <breno.lima@nxp.com> Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
		
			
				
	
	
		
			116 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			116 lines
		
	
	
		
			3.0 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.
 | |
| 
 |