1Overview
2--------
3The MPC8544DS system is similar to the 85xx CDS systems such
4as the MPC8548CDS due to the similar E500 core.  However, it
5is placed on the same board as the 8641 HPCN system.
6
7
8Flash Banks
9-----------
10Like the 85xx CDS systems, the 8544 DS board has two flash banks.
11They are both present on boot, but there locations can be swapped
12using the dip-switch SW10, bit 2.
13
14However, unlike the CDS systems, but similar to the 8641 HPCN
15board, a runtime reset through the FPGA can also affect a swap
16on the flash bank mappings for the next reset cycle.
17
18Irrespective of the switch SW10[2], booting is always from the
19boot bank at 0xfff8_0000.
20
21
22Memory Map
23----------
24
250xff80_0000 - 0xffbf_ffff	Alternate bank		4MB
260xffc0_0000 - 0xffff_ffff	Boot bank		4MB
27
280xffb8_0000			Alternate image start	512KB
290xfff8_0000			Boot image start	512KB
30
31
32Flashing Images
33---------------
34
35For example, to place a new image in the alternate flash bank
36and then reset with that new image temporarily, use this:
37
38    tftp 1000000 u-boot.bin.8544ds
39    erase ffb80000 ffbfffff
40    cp.b 1000000 ffb80000 80000
41    pixis_reset altbank
42
43
44To overwrite the image in the boot flash bank:
45
46    tftp 1000000 u-boot.bin.8544ds
47    protect off all
48    erase fff80000 ffffffff
49    cp.b 1000000 fff80000 80000
50
51Other example U-Boot image and flash manipulations examples
52can be found in the README.mpc85xxcds file as well.
53
54
55The pixis_reset command
56-----------------------
57A new command, "pixis_reset", is introduced to reset mpc8641hpcn board
58using the FPGA sequencer.  When the board restarts, it has the option
59of using either the current or alternate flash bank as the boot
60image, with or without the watchdog timer enabled, and finally with
61or without frequency changes.
62
63Usage is;
64
65	pixis_reset
66	pixis_reset altbank
67	pixis_reset altbank wd
68	pixis_reset altbank cf <SYSCLK freq> <COREPLL ratio> <MPXPLL ratio>
69	pixis_reset cf <SYSCLK freq> <COREPLL ratio> <MPXPLL ratio>
70
71Examples;
72
73	/* reset to current bank, like "reset" command */
74	pixis_reset
75
76	/* reset board but use the to alternate flash bank */
77	pixis_reset altbank
78
79	/* reset board, use alternate flash bank with watchdog timer enabled*/
80	pixis_reset altbank wd
81
82	/* reset board to alternate bank with frequency changed.
83	 * 40 is SYSCLK, 2.5 is COREPLL ratio, 10 is MPXPLL ratio
84	 */
85	pixis-reset altbank cf 40 2.5 10
86
87Valid clock choices are in the 8641 Reference Manuals.
88
89
90Using the Device Tree Source File
91---------------------------------
92To create the DTB (Device Tree Binary) image file,
93use a command similar to this:
94
95    dtc -b 0 -f -I dts -O dtb mpc8544ds.dts > mpc8544ds.dtb
96
97Likely, that .dts file will come from here;
98
99    linux-2.6/arch/powerpc/boot/dts/mpc8544ds.dts
100
101After placing the DTB file in your TFTP disk area,
102you can download that dtb file using a command like:
103
104    tftp 900000 mpc8544ds.dtb
105
106Burn it to flash if you want.
107
108
109Booting Linux
110-------------
111
112Place a linux uImage in the TFTP disk area too.
113
114    tftp 1000000 uImage.8544
115    tftp 900000 mpc8544ds.dtb
116    bootm 1000000 - 900000
117
118Watch your ethact, netdev and bootargs U-Boot environment variables.
119You may want to do something like this too:
120
121    setenv ethact eTSEC3
122    setenv netdev eth1
123