1============================================
2The Intel Assabet (SA-1110 evaluation) board
3============================================
4
5Please see:
6http://developer.intel.com
7
8Also some notes from John G Dorsey <jd5q@andrew.cmu.edu>:
9http://www.cs.cmu.edu/~wearable/software/assabet.html
10
11
12Building the kernel
13-------------------
14
15To build the kernel with current defaults::
16
17	make assabet_defconfig
18	make oldconfig
19	make zImage
20
21The resulting kernel image should be available in linux/arch/arm/boot/zImage.
22
23
24Installing a bootloader
25-----------------------
26
27A couple of bootloaders able to boot Linux on Assabet are available:
28
29BLOB (http://www.lartmaker.nl/lartware/blob/)
30
31   BLOB is a bootloader used within the LART project.  Some contributed
32   patches were merged into BLOB to add support for Assabet.
33
34Compaq's Bootldr + John Dorsey's patch for Assabet support
35(http://www.handhelds.org/Compaq/bootldr.html)
36(http://www.wearablegroup.org/software/bootldr/)
37
38   Bootldr is the bootloader developed by Compaq for the iPAQ Pocket PC.
39   John Dorsey has produced add-on patches to add support for Assabet and
40   the JFFS filesystem.
41
42RedBoot (http://sources.redhat.com/redboot/)
43
44   RedBoot is a bootloader developed by Red Hat based on the eCos RTOS
45   hardware abstraction layer.  It supports Assabet amongst many other
46   hardware platforms.
47
48RedBoot is currently the recommended choice since it's the only one to have
49networking support, and is the most actively maintained.
50
51Brief examples on how to boot Linux with RedBoot are shown below.  But first
52you need to have RedBoot installed in your flash memory.  A known to work
53precompiled RedBoot binary is available from the following location:
54
55- ftp://ftp.netwinder.org/users/n/nico/
56- ftp://ftp.arm.linux.org.uk/pub/linux/arm/people/nico/
57- ftp://ftp.handhelds.org/pub/linux/arm/sa-1100-patches/
58
59Look for redboot-assabet*.tgz.  Some installation infos are provided in
60redboot-assabet*.txt.
61
62
63Initial RedBoot configuration
64-----------------------------
65
66The commands used here are explained in The RedBoot User's Guide available
67on-line at http://sources.redhat.com/ecos/docs.html.
68Please refer to it for explanations.
69
70If you have a CF network card (my Assabet kit contained a CF+ LP-E from
71Socket Communications Inc.), you should strongly consider using it for TFTP
72file transfers.  You must insert it before RedBoot runs since it can't detect
73it dynamically.
74
75To initialize the flash directory::
76
77	fis init -f
78
79To initialize the non-volatile settings, like whether you want to use BOOTP or
80a static IP address, etc, use this command::
81
82	fconfig -i
83
84
85Writing a kernel image into flash
86---------------------------------
87
88First, the kernel image must be loaded into RAM.  If you have the zImage file
89available on a TFTP server::
90
91	load zImage -r -b 0x100000
92
93If you rather want to use Y-Modem upload over the serial port::
94
95	load -m ymodem -r -b 0x100000
96
97To write it to flash::
98
99	fis create "Linux kernel" -b 0x100000 -l 0xc0000
100
101
102Booting the kernel
103------------------
104
105The kernel still requires a filesystem to boot.  A ramdisk image can be loaded
106as follows::
107
108	load ramdisk_image.gz -r -b 0x800000
109
110Again, Y-Modem upload can be used instead of TFTP by replacing the file name
111by '-y ymodem'.
112
113Now the kernel can be retrieved from flash like this::
114
115	fis load "Linux kernel"
116
117or loaded as described previously.  To boot the kernel::
118
119	exec -b 0x100000 -l 0xc0000
120
121The ramdisk image could be stored into flash as well, but there are better
122solutions for on-flash filesystems as mentioned below.
123
124
125Using JFFS2
126-----------
127
128Using JFFS2 (the Second Journalling Flash File System) is probably the most
129convenient way to store a writable filesystem into flash.  JFFS2 is used in
130conjunction with the MTD layer which is responsible for low-level flash
131management.  More information on the Linux MTD can be found on-line at:
132http://www.linux-mtd.infradead.org/.  A JFFS howto with some infos about
133creating JFFS/JFFS2 images is available from the same site.
134
135For instance, a sample JFFS2 image can be retrieved from the same FTP sites
136mentioned below for the precompiled RedBoot image.
137
138To load this file::
139
140	load sample_img.jffs2 -r -b 0x100000
141
142The result should look like::
143
144	RedBoot> load sample_img.jffs2 -r -b 0x100000
145	Raw file loaded 0x00100000-0x00377424
146
147Now we must know the size of the unallocated flash::
148
149	fis free
150
151Result::
152
153	RedBoot> fis free
154	  0x500E0000 .. 0x503C0000
155
156The values above may be different depending on the size of the filesystem and
157the type of flash.  See their usage below as an example and take care of
158substituting yours appropriately.
159
160We must determine some values::
161
162	size of unallocated flash:	0x503c0000 - 0x500e0000 = 0x2e0000
163	size of the filesystem image:	0x00377424 - 0x00100000 = 0x277424
164
165We want to fit the filesystem image of course, but we also want to give it all
166the remaining flash space as well.  To write it::
167
168	fis unlock -f 0x500E0000 -l 0x2e0000
169	fis erase -f 0x500E0000 -l 0x2e0000
170	fis write -b 0x100000 -l 0x277424 -f 0x500E0000
171	fis create "JFFS2" -n -f 0x500E0000 -l 0x2e0000
172
173Now the filesystem is associated to a MTD "partition" once Linux has discovered
174what they are in the boot process.  From Redboot, the 'fis list' command
175displays them::
176
177	RedBoot> fis list
178	Name              FLASH addr  Mem addr    Length      Entry point
179	RedBoot           0x50000000  0x50000000  0x00020000  0x00000000
180	RedBoot config    0x503C0000  0x503C0000  0x00020000  0x00000000
181	FIS directory     0x503E0000  0x503E0000  0x00020000  0x00000000
182	Linux kernel      0x50020000  0x00100000  0x000C0000  0x00000000
183	JFFS2             0x500E0000  0x500E0000  0x002E0000  0x00000000
184
185However Linux should display something like::
186
187	SA1100 flash: probing 32-bit flash bus
188	SA1100 flash: Found 2 x16 devices at 0x0 in 32-bit mode
189	Using RedBoot partition definition
190	Creating 5 MTD partitions on "SA1100 flash":
191	0x00000000-0x00020000 : "RedBoot"
192	0x00020000-0x000e0000 : "Linux kernel"
193	0x000e0000-0x003c0000 : "JFFS2"
194	0x003c0000-0x003e0000 : "RedBoot config"
195	0x003e0000-0x00400000 : "FIS directory"
196
197What's important here is the position of the partition we are interested in,
198which is the third one.  Within Linux, this correspond to /dev/mtdblock2.
199Therefore to boot Linux with the kernel and its root filesystem in flash, we
200need this RedBoot command::
201
202	fis load "Linux kernel"
203	exec -b 0x100000 -l 0xc0000 -c "root=/dev/mtdblock2"
204
205Of course other filesystems than JFFS might be used, like cramfs for example.
206You might want to boot with a root filesystem over NFS, etc.  It is also
207possible, and sometimes more convenient, to flash a filesystem directly from
208within Linux while booted from a ramdisk or NFS.  The Linux MTD repository has
209many tools to deal with flash memory as well, to erase it for example.  JFFS2
210can then be mounted directly on a freshly erased partition and files can be
211copied over directly.  Etc...
212
213
214RedBoot scripting
215-----------------
216
217All the commands above aren't so useful if they have to be typed in every
218time the Assabet is rebooted.  Therefore it's possible to automate the boot
219process using RedBoot's scripting capability.
220
221For example, I use this to boot Linux with both the kernel and the ramdisk
222images retrieved from a TFTP server on the network::
223
224	RedBoot> fconfig
225	Run script at boot: false true
226	Boot script:
227	Enter script, terminate with empty line
228	>> load zImage -r -b 0x100000
229	>> load ramdisk_ks.gz -r -b 0x800000
230	>> exec -b 0x100000 -l 0xc0000
231	>>
232	Boot script timeout (1000ms resolution): 3
233	Use BOOTP for network configuration: true
234	GDB connection port: 9000
235	Network debug at boot time: false
236	Update RedBoot non-volatile configuration - are you sure (y/n)? y
237
238Then, rebooting the Assabet is just a matter of waiting for the login prompt.
239
240
241
242Nicolas Pitre
243nico@fluxnic.net
244
245June 12, 2001
246
247
248Status of peripherals in -rmk tree (updated 14/10/2001)
249-------------------------------------------------------
250
251Assabet:
252 Serial ports:
253  Radio:		TX, RX, CTS, DSR, DCD, RI
254   - PM:		Not tested.
255   - COM:		TX, RX, CTS, DSR, DCD, RTS, DTR, PM
256   - PM:		Not tested.
257   - I2C:		Implemented, not fully tested.
258   - L3:		Fully tested, pass.
259   - PM:		Not tested.
260
261 Video:
262  - LCD:		Fully tested.  PM
263
264   (LCD doesn't like being blanked with neponset connected)
265
266  - Video out:		Not fully
267
268 Audio:
269  UDA1341:
270  -  Playback:		Fully tested, pass.
271  -  Record:		Implemented, not tested.
272  -  PM:			Not tested.
273
274  UCB1200:
275  -  Audio play:	Implemented, not heavily tested.
276  -  Audio rec:		Implemented, not heavily tested.
277  -  Telco audio play:	Implemented, not heavily tested.
278  -  Telco audio rec:	Implemented, not heavily tested.
279  -  POTS control:	No
280  -  Touchscreen:	Yes
281  -  PM:		Not tested.
282
283 Other:
284  - PCMCIA:
285  - LPE:		Fully tested, pass.
286  - USB:		No
287  - IRDA:
288  - SIR:		Fully tested, pass.
289  - FIR:		Fully tested, pass.
290  - PM:			Not tested.
291
292Neponset:
293 Serial ports:
294  - COM1,2:		TX, RX, CTS, DSR, DCD, RTS, DTR
295  - PM:			Not tested.
296  - USB:		Implemented, not heavily tested.
297  - PCMCIA:		Implemented, not heavily tested.
298  - CF:			Implemented, not heavily tested.
299  - PM:			Not tested.
300
301More stuff can be found in the -np (Nicolas Pitre's) tree.
302