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Based on kernel version 3.13. Page generated on 2014-01-20 22:00 EST.

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