xref: /openbmc/u-boot/board/armltd/integrator/README (revision b3820ba9)
1
2		U-Boot for ARM Integrator Development Platforms
3
4			Peter Pearse, ARM Ltd.
5			peter.pearse@arm.com
6			     www.arm.com
7
8Manuals available from :-
9http://www.arm.com/products/DevTools/Hardware_Platforms.html
10
11Overview :
12--------
13There are two Integrator variants - Integrator/AP and Integrator/CP.
14Each may be fitted with a variety of core modules (CMs).
15Each CM consists of a ARM processor core and associated hardware e.g
16	FPGA implementing various controllers and/or register
17	SSRAM
18	SDRAM
19	RAM controllers
20	clock generators etc.
21CMs may be fitted with varying amounts of SDRAM using a DIMM socket.
22
23Boot Methods :
24------------
25Integrator platforms can be configured to use U-Boot in at least three ways :-
26a) Run ARM boot monitor, manually run U-Boot image from flash
27b) Run ARM boot monitor, automatically run U-Boot image from flash
28c) Run U-Boot image direct from flash.
29
30In cases a) and b) the ARM boot monitor will have configured the CM and mapped
31writeable memory to 0x00000000 in the Integrator address space.
32U-Boot has to carry out minimal configration before standard code is run.
33
34In case c) it may be necessary for U-Boot to perform CM dependent initialization.
35
36Configuring U-Boot :
37------------------
38	The makefile contains targets for Integrator platforms of both types
39fitted with all current variants of CM.
40
41	There are also targets independent of CM. These may not be suitable for
42boot process c) above. They have been preserved for backward compatibility with
43existing build processes.
44
45Code Hierarchy Applied :
46----------------------
47Code specific to initialization of a particular ARM processor has been placed in
48cpu/arm<>/start.S so that it may be used by other boards.
49
50However, to avoid duplicating code through all processor files, a generic core
51for ARM Integrator CMs has been added
52
53	arch/arm/cpu/arm_intcm
54
55Otherwise. for example,  the standard CM reset via the CM control register would
56need placing in each CM processor file......
57
58Code specific to the initialization of the CM, rather than the cpu, and initialization
59of the Integrator board itself, has been placed in
60
61	board/integrator<>/platform.S
62	board/integrator<>/integrator<>.c
63
64Targets
65=======
66The U-Boot make targets map to the available core modules as below.
67
68Integrator/AP is no longer available from ARM.
69Core modules marked ** are also no longer available.
70
71ap720t_config		** CM720T
72ap920t_config		** CM920T
73ap926ejs_config	Integrator Core Module for ARM926EJ-STM
74ap946es_config		Integrator Core Module for ARM946E-STM
75cp920t_config		** CM920T
76cp926ejs_config	Integrator Core Module for ARM926EJ-STM
77cp946es_config		Integrator Core Module for ARM946E-STM
78cp1136_config		Integrator Core Module ARM1136JF-S  TM
79
80The final groups of targets are for core modules where no explicit cpu
81code has yet been added to U-Boot i.e. they all use the same U-Boot binary
82using the generic "arm_intcm" core:
83
84ap966_config			Integrator Core Module for ARM966E-S TM
85ap922_config			Integrator Core Module for ARM922T TM with ETM
86ap922_XA10_config		Integrator Core Module for ARM922T using Altera Excalibur
87ap7_config			** CM7TDMI
88integratorap_config
89ap_config
90
91
92cp966_config			Integrator Core Module for ARM966E-S TM
93cp922_config			Integrator Core Module for ARM922T TM with ETM
94cp922_XA10_config		Integrator Core Module for ARM922T using Altera Excalibur
95cp1026_config			Integrator Core Module ARM1026EJ-S TM
96integratorcp_config
97cp_config
98
99The Makefile targets call board/integrator<>/split_by_variant.sh
100to configure various defines in include/configs/integrator<>.h
101to indicate the core module & core configuration and ensure that
102board/integrator<>/u-boot.lds loads the cpu object first in the U-Boot image.
103
104*********************************
105Because of this mechanism
106> make clean
107must be run before each change in configuration
108*********************************
109