diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /Documentation/arm/IXP4xx |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'Documentation/arm/IXP4xx')
-rw-r--r-- | Documentation/arm/IXP4xx | 174 |
1 files changed, 174 insertions, 0 deletions
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1 | |||
2 | ------------------------------------------------------------------------- | ||
3 | Release Notes for Linux on Intel's IXP4xx Network Processor | ||
4 | |||
5 | Maintained by Deepak Saxena <dsaxena@plexity.net> | ||
6 | ------------------------------------------------------------------------- | ||
7 | |||
8 | 1. Overview | ||
9 | |||
10 | Intel's IXP4xx network processor is a highly integrated SOC that | ||
11 | is targeted for network applications, though it has become popular | ||
12 | in industrial control and other areas due to low cost and power | ||
13 | consumption. The IXP4xx family currently consists of several processors | ||
14 | that support different network offload functions such as encryption, | ||
15 | routing, firewalling, etc. The IXP46x family is an updated version which | ||
16 | supports faster speeds, new memory and flash configurations, and more | ||
17 | integration such as an on-chip I2C controller. | ||
18 | |||
19 | For more information on the various versions of the CPU, see: | ||
20 | |||
21 | http://developer.intel.com/design/network/products/npfamily/ixp4xx.htm | ||
22 | |||
23 | Intel also made the IXCP1100 CPU for sometime which is an IXP4xx | ||
24 | stripped of much of the network intelligence. | ||
25 | |||
26 | 2. Linux Support | ||
27 | |||
28 | Linux currently supports the following features on the IXP4xx chips: | ||
29 | |||
30 | - Dual serial ports | ||
31 | - PCI interface | ||
32 | - Flash access (MTD/JFFS) | ||
33 | - I2C through GPIO on IXP42x | ||
34 | - GPIO for input/output/interrupts | ||
35 | See include/asm-arm/arch-ixp4xx/platform.h for access functions. | ||
36 | - Timers (watchdog, OS) | ||
37 | |||
38 | The following components of the chips are not supported by Linux and | ||
39 | require the use of Intel's propietary CSR softare: | ||
40 | |||
41 | - USB device interface | ||
42 | - Network interfaces (HSS, Utopia, NPEs, etc) | ||
43 | - Network offload functionality | ||
44 | |||
45 | If you need to use any of the above, you need to download Intel's | ||
46 | software from: | ||
47 | |||
48 | http://developer.intel.com/design/network/products/npfamily/ixp425swr1.htm | ||
49 | |||
50 | DO NOT POST QUESTIONS TO THE LINUX MAILING LISTS REGARDING THE PROPIETARY | ||
51 | SOFTWARE. | ||
52 | |||
53 | There are several websites that provide directions/pointers on using | ||
54 | Intel's software: | ||
55 | |||
56 | http://ixp4xx-osdg.sourceforge.net/ | ||
57 | Open Source Developer's Guide for using uClinux and the Intel libraries | ||
58 | |||
59 | http://gatewaymaker.sourceforge.net/ | ||
60 | Simple one page summary of building a gateway using an IXP425 and Linux | ||
61 | |||
62 | http://ixp425.sourceforge.net/ | ||
63 | ATM device driver for IXP425 that relies on Intel's libraries | ||
64 | |||
65 | 3. Known Issues/Limitations | ||
66 | |||
67 | 3a. Limited inbound PCI window | ||
68 | |||
69 | The IXP4xx family allows for up to 256MB of memory but the PCI interface | ||
70 | can only expose 64MB of that memory to the PCI bus. This means that if | ||
71 | you are running with > 64MB, all PCI buffers outside of the accessible | ||
72 | range will be bounced using the routines in arch/arm/common/dmabounce.c. | ||
73 | |||
74 | 3b. Limited outbound PCI window | ||
75 | |||
76 | IXP4xx provides two methods of accessing PCI memory space: | ||
77 | |||
78 | 1) A direct mapped window from 0x48000000 to 0x4bffffff (64MB). | ||
79 | To access PCI via this space, we simply ioremap() the BAR | ||
80 | into the kernel and we can use the standard read[bwl]/write[bwl] | ||
81 | macros. This is the preffered method due to speed but it | ||
82 | limits the system to just 64MB of PCI memory. This can be | ||
83 | problamatic if using video cards and other memory-heavy devices. | ||
84 | |||
85 | 2) If > 64MB of memory space is required, the IXP4xx can be | ||
86 | configured to use indirect registers to access PCI This allows | ||
87 | for up to 128MB (0x48000000 to 0x4fffffff) of memory on the bus. | ||
88 | The disadvantadge of this is that every PCI access requires | ||
89 | three local register accesses plus a spinlock, but in some | ||
90 | cases the performance hit is acceptable. In addition, you cannot | ||
91 | mmap() PCI devices in this case due to the indirect nature | ||
92 | of the PCI window. | ||
93 | |||
94 | By default, the direct method is used for performance reasons. If | ||
95 | you need more PCI memory, enable the IXP4XX_INDIRECT_PCI config option. | ||
96 | |||
97 | 3c. GPIO as Interrupts | ||
98 | |||
99 | Currently the code only handles level-sensitive GPIO interrupts | ||
100 | |||
101 | 4. Supported platforms | ||
102 | |||
103 | ADI Engineering Coyote Gateway Reference Platform | ||
104 | http://www.adiengineering.com/productsCoyote.html | ||
105 | |||
106 | The ADI Coyote platform is reference design for those building | ||
107 | small residential/office gateways. One NPE is connected to a 10/100 | ||
108 | interface, one to 4-port 10/100 switch, and the third to and ADSL | ||
109 | interface. In addition, it also supports to POTs interfaces connected | ||
110 | via SLICs. Note that those are not supported by Linux ATM. Finally, | ||
111 | the platform has two mini-PCI slots used for 802.11[bga] cards. | ||
112 | Finally, there is an IDE port hanging off the expansion bus. | ||
113 | |||
114 | Gateworks Avila Network Platform | ||
115 | http://www.gateworks.com/avila_sbc.htm | ||
116 | |||
117 | The Avila platform is basically and IXDP425 with the 4 PCI slots | ||
118 | replaced with mini-PCI slots and a CF IDE interface hanging off | ||
119 | the expansion bus. | ||
120 | |||
121 | Intel IXDP425 Development Platform | ||
122 | http://developer.intel.com/design/network/products/npfamily/ixdp425.htm | ||
123 | |||
124 | This is Intel's standard reference platform for the IXDP425 and is | ||
125 | also known as the Richfield board. It contains 4 PCI slots, 16MB | ||
126 | of flash, two 10/100 ports and one ADSL port. | ||
127 | |||
128 | Intel IXDP465 Development Platform | ||
129 | http://developer.intel.com/design/network/products/npfamily/ixdp465.htm | ||
130 | |||
131 | This is basically an IXDP425 with an IXP465 and 32M of flash instead | ||
132 | of just 16. | ||
133 | |||
134 | Intel IXDPG425 Development Platform | ||
135 | |||
136 | This is basically and ADI Coyote board with a NEC EHCI controller | ||
137 | added. One issue with this board is that the mini-PCI slots only | ||
138 | have the 3.3v line connected, so you can't use a PCI to mini-PCI | ||
139 | adapter with an E100 card. So to NFS root you need to use either | ||
140 | the CSR or a WiFi card and a ramdisk that BOOTPs and then does | ||
141 | a pivot_root to NFS. | ||
142 | |||
143 | Motorola PrPMC1100 Processor Mezanine Card | ||
144 | http://www.fountainsys.com/datasheet/PrPMC1100.pdf | ||
145 | |||
146 | The PrPMC1100 is based on the IXCP1100 and is meant to plug into | ||
147 | and IXP2400/2800 system to act as the system controller. It simply | ||
148 | contains a CPU and 16MB of flash on the board and needs to be | ||
149 | plugged into a carrier board to function. Currently Linux only | ||
150 | supports the Motorola PrPMC carrier board for this platform. | ||
151 | See https://mcg.motorola.com/us/ds/pdf/ds0144.pdf for info | ||
152 | on the carrier board. | ||
153 | |||
154 | 5. TODO LIST | ||
155 | |||
156 | - Add support for Coyote IDE | ||
157 | - Add support for edge-based GPIO interrupts | ||
158 | - Add support for CF IDE on expansion bus | ||
159 | |||
160 | 6. Thanks | ||
161 | |||
162 | The IXP4xx work has been funded by Intel Corp. and MontaVista Software, Inc. | ||
163 | |||
164 | The following people have contributed patches/comments/etc: | ||
165 | |||
166 | Lennerty Buytenhek | ||
167 | Lutz Jaenicke | ||
168 | Justin Mayfield | ||
169 | Robert E. Ranslam | ||
170 | [I know I've forgotten others, please email me to be added] | ||
171 | |||
172 | ------------------------------------------------------------------------- | ||
173 | |||
174 | Last Update: 01/04/2005 | ||