xref: /openbmc/u-boot/board/sbc8548/README (revision 472d5460)
1Intro:
2======
3
4The SBC8548 is a stand alone single board computer with a 1GHz
5MPC8548 CPU, 8MB boot flash, 64MB user flash and, 256MB DDR2 400MHz
6memory. It also has 128MB SDRAM 100MHz LBC memory, with both a PCI-e,
7and a PCI-X slot, dual mini-DB9 for UART, and dual RJ-45 for eTSEC
8ethernet connections.
9
10U-boot Configuration:
11=====================
12
13The following possible u-boot configuration targets are available:
14
15	1) sbc8548_config
16	2) sbc8548_PCI_33_config
17	3) sbc8548_PCI_66_config
18	4) sbc8548_PCI_33_PCIE_config
19	5) sbc8548_PCI_66_PCIE_config
20
21Generally speaking, most people should choose to use #5.  Details
22of each choice are listed below.
23
24Choice #1 does not enable CONFIG_PCI, and assumes that the PCI slot
25will be left empty (M66EN high), and so the board will operate with
26a base clock of 66MHz.	Note that you need both PCI enabled in u-boot
27and linux in order to have functional PCI under linux.
28
29The second enables PCI support and builds for a 33MHz clock rate.  Note
30that if a 33MHz 32bit card is inserted in the slot, then the whole board
31will clock down to a 33MHz base clock instead of the default 66MHz.  This
32will change the baud clocks and mess up your serial console output if you
33were previously running at 66MHz.  If you want to use a 33MHz PCI card,
34then you should build a U-Boot with a _PCI_33_ config and store this
35to flash prior to powering down the board and inserting the 33MHz PCI
36card. [The above discussion assumes that the SW2[1-4] has not been changed
37to reflect a different CCB:SYSCLK ratio]
38
39The third option builds PCI support in, and leaves the clocking at the
40default 66MHz.	Options four and five are just repeats of option two
41and three, but with PCI-e support enabled as well.
42
43PCI output listing with an intel e1000 PCI-x and a Syskonnect SK-9Exx
44is shown below for sbc8548_PCI_66_PCIE_config.	(Note that PCI-e with
45a 33MHz PCI configuration is currently untested.)
46
47    => pci 0
48    Scanning PCI devices on bus 0
49    BusDevFun  VendorId	  DeviceId   Device Class	Sub-Class
50    _____________________________________________________________
51    00.00.00   0x1057	  0x0012     Processor		     0x20
52    00.01.00   0x8086	  0x1026     Network controller	     0x00
53    => pci 1
54    Scanning PCI devices on bus 1
55    BusDevFun  VendorId	  DeviceId   Device Class	Sub-Class
56    _____________________________________________________________
57    01.00.00   0x1957	  0x0012     Processor		     0x20
58    => pci 2
59    Scanning PCI devices on bus 2
60    BusDevFun  VendorId	  DeviceId   Device Class	Sub-Class
61    _____________________________________________________________
62    02.00.00   0x1148	  0x9e00     Network controller	     0x00
63    =>
64
65Memory Size and using SPD:
66==========================
67
68The default configuration uses hard coded memory configuration settings
69for 256MB of DDR2 @400MHz.  It does not by default use the DDR2 SPD
70EEPROM data to read what memory is installed.
71
72There is a hardware errata, which causes the older local bus SDRAM
73SPD EEPROM to land at the same address as the DDR2 SPD EEPROM, so
74that the SPD data can not be read reliably.  You can test if your
75board has the errata fix by running "i2c probe".  If you see 0x53
76as a valid device, it has been fixed.  If you only see 0x50, 0x51
77then your board does not have the fix.
78
79You can also visually inspect the board to see if this hardware
80fix has been applied:
81
82      1) Remove R314 (RES-R0174-033, 1K, 0603). R314 is located on
83	 the back of the PCB behind the DDR SDRAM SODIMM connector.
84      2) Solder RES-R0174-033 (1K, 0603) resistor from R314 pin 2 pad
85	 to R313 pin 2.	 Pin 2 for each resistor is the end of the
86	 resistor closest to the CPU.
87
88Boards without the mod will have R314 and R313 in parallel, like "||".
89After the mod, they will be touching and form an "L" shape.
90
91If you want to upgrade to larger RAM size, you can simply enable
92	#define CONFIG_SPD_EEPROM
93	#define CONFIG_DDR_SPD
94in include/configs/sbc8548.h file.  (The lines are already there
95but listed as #undef).
96
97If you did the i2c test, and your board does not have the errata
98fix, then you will have to physically remove the LBC 128MB DIMM
99from the board's socket to resolve the above i2c address overlap
100issue and allow SPD autodetection of RAM to work.
101
102
103Updating U-boot with U-boot:
104============================
105
106Note that versions of u-boot up to and including 2009.08 had u-boot stored
107at 0xfff8_0000 -> 0xffff_ffff (512k).  Currently it is being stored from
1080xfffa_0000 -> 0xffff_ffff (384k).  If you use an old macro/script to
109update u-boot with u-boot and it uses the old address, you will render
110your board inoperable, and you will require JTAG recovery.
111
112The following steps list how to update with the current address:
113
114	tftp u-boot.bin
115	md 200000 10
116	protect off all
117	erase fffa0000 ffffffff
118	cp.b 200000 fffa0000 60000
119	md fffa0000 10
120	protect on all
121
122The "md" steps in the above are just a precautionary step that allow
123you to confirm the u-boot version that was downloaded, and then confirm
124that it was copied to flash.
125
126The above assumes that you are using the default board settings which
127have u-boot in the 8MB flash, tied to /CS0.
128
129If you are running the default 8MB /CS0 settings but want to store an
130image in the SODIMM that is built with CONFIG_SYS_ALT_BOOT enabled,
131(as a backup, etc) then the steps will become:
132
133	tftp u-boot.bin
134	md 200000 10
135	protect off all
136	era eff00000 efffffff
137	cp.b 200000 eff00000 100000
138	md eff00000 10
139	protect on all
140
141Finally, if you are running the alternate 64MB /CS0 settings and want
142to update the in-use u-boot image, then (again with CONFIG_SYS_ALT_BOOT
143enabled) the steps will become:
144
145	tftp u-boot.bin
146	md 200000 10
147	protect off all
148	era fff00000 ffffffff
149	cp.b 200000 fff00000 100000
150	md fff00000 10
151	protect on all
152
153
154Hardware Reference:
155===================
156
157The following contains some summary information on hardware settings
158that are relevant to u-boot, based on the board manual.	 For the
159most up to date and complete details of the board, please request the
160reference manual ERG-00327-001.pdf from www.windriver.com
161
162Boot flash:
163	intel V28F640Jx, 8192x8 (one device) at 0xff80_0000
164
165Sodimm flash:
166	intel V28F128Jx, 16384x8 (4 devices) at 0xfb80_0000
167	Note that this address reflects the default setting for
168	the JTAG debugging tools, but since the alignment is
169	rather inconvenient, u-boot puts it at 0xec00_0000.
170
171
172	Jumpers:
173
174Jumper		Name		ON		OFF
175----------------------------------------------------------------
176JP12		CS0/CS6 swap	see note[*]	see note[*]
177
178JP13		SODIMM flash	write OK	writes disabled
179		write prot.
180
181JP14		HRESET/TRST	joined		isolated
182
183JP15		PWR ON		when AC pwr	use S1 for on/off
184
185JP16		Demo LEDs	lit		not lit
186
187JP19		PCI mode	PCI		PCI-X
188
189
190[*]JP12, when jumpered parallel to the SODIMM, puts the boot flash
191onto /CS0 and the SODIMM flash on /CS6 (default).  When JP12
192is jumpered parallel to the LBC-SDRAM, then /CS0 is for the
193SODIMM flash and /CS6 is for the boot flash.  Note that in this
194alternate setting, you also need to switch SW2.8 to ON.
195See the setting CONFIG_SYS_ALT_BOOT if you want to use this setting
196and boot u-boot from the 64MB SODIMM
197
198
199	Switches:
200
201The defaults are marked with a *
202
203Name		Desc.			ON		OFF
204------------------------------------------------------------------
205S1		Pwr toggle		n/a		n/a
206
207SW2.1		CFG_SYS_PLL0		1		0*
208SW2.2		CFG_SYS_PLL1		1*		0
209SW2.3		CFG_SYS_PLL2		1*		0
210SW2.4		CFG_SYS_PLL3		1		0*
211SW2.5		CFG_CORE_PLL0		1*		0
212SW2.6		CFG_CORE_PLL1		1		0*
213SW2.7		CFG_CORE_PLL2		1*		0
214SW2.8		CFG_ROM_LOC1		1		0*
215
216SW3.1		CFG_HOST_AGT0		1*		0
217SW3.2		CFG_HOST_AGT1		1*		0
218SW3.3		CFG_HOST_AGT2		1*		0
219SW3.4		CFG_IO_PORTS0		1*		0
220SW3.5		CFG_IO_PORTS0		1		0*
221SW3.6		CFG_IO_PORTS0		1		0*
222
223SerDes CLK(MHz)		SW5.1		SW5.2
224----------------------------------------------
22525			0		0
226100*			1		0
227125			0		1
228200			1		1
229
230SerDes CLK spread	SW5.3		SW5.4
231----------------------------------------------
232+/- 0.25%		0		0
233-0.50%			1		0
234-0.75%			0		1
235No Spread*		1		1
236
237SW4 settings are readable from the EPLD and are currently not used for
238any hardware settings (i.e. user configuration switches).
239
240	LEDs:
241
242Name		Desc.			ON		OFF
243------------------------------------------------------------------
244D13		PCI/PCI-X		PCI-X		PCI
245D14		3.3V PWR		3.3V		no power
246D15		SYSCLK			66MHz		33MHz
247
248
249	Default Memory Map:
250
251start		end		CS<n>	width	Desc.
252----------------------------------------------------------------------
2530000_0000	0fff_ffff	MCS0,1	64	DDR2 (256MB)
254f000_0000	f7ff_ffff	CS3,4	32	LB SDRAM (128MB)
255f800_0000	f8b0_1fff	CS5	-	EPLD
256fb80_0000	ff7f_ffff	CS6	32	SODIMM flash (64MB) [*]
257ff80_0000	ffff_ffff	CS0	8	Boot flash (8MB)
258
259[*] fb80 represents the default programmed by WR JTAG register files,
260    but u-boot places the flash at either ec00 or fc00 based on JP12.
261
262The EPLD on CS5 demuxes the following devices at the following offsets:
263
264offset		size	width	device
265--------------------------------------------------------
2660		1fff	8	7 segment display LED
26710_0000		1fff	4	user switches
26830_0000		1fff	4	HW Rev. register
269b0_0000		1fff	8	8kB EEPROM
270