1===========================================================
  2Release Notes for Linux on Intel's IXP4xx Network Processor
  3===========================================================
  4
  5Maintained by Deepak Saxena <dsaxena@plexity.net>
  6-------------------------------------------------------------------------
  7
  81. Overview
  9
 10Intel's IXP4xx network processor is a highly integrated SOC that
 11is targeted for network applications, though it has become popular
 12in industrial control and other areas due to low cost and power
 13consumption. The IXP4xx family currently consists of several processors
 14that support different network offload functions such as encryption,
 15routing, firewalling, etc. The IXP46x family is an updated version which
 16supports faster speeds, new memory and flash configurations, and more
 17integration such as an on-chip I2C controller.
 18
 19For more information on the various versions of the CPU, see:
 20
 21   http://developer.intel.com/design/network/products/npfamily/ixp4xx.htm
 22
 23Intel also made the IXCP1100 CPU for sometime which is an IXP4xx
 24stripped of much of the network intelligence.
 25
 262. Linux Support
 27
 28Linux 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 arch/arm/mach-ixp4xx/include/mach/platform.h for access functions.
 36- Timers (watchdog, OS)
 37
 38The following components of the chips are not supported by Linux and
 39require the use of Intel's proprietary CSR software:
 40
 41- USB device interface
 42- Network interfaces (HSS, Utopia, NPEs, etc)
 43- Network offload functionality
 44
 45If you need to use any of the above, you need to download Intel's
 46software from:
 47
 48   http://developer.intel.com/design/network/products/npfamily/ixp425.htm
 49
 50DO NOT POST QUESTIONS TO THE LINUX MAILING LISTS REGARDING THE PROPRIETARY
 51SOFTWARE.
 52
 53There are several websites that provide directions/pointers on using
 54Intel's software:
 55
 56   - http://sourceforge.net/projects/ixp4xx-osdg/
 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
 653. Known Issues/Limitations
 66
 673a. Limited inbound PCI window
 68
 69The IXP4xx family allows for up to 256MB of memory but the PCI interface
 70can only expose 64MB of that memory to the PCI bus. This means that if
 71you are running with > 64MB, all PCI buffers outside of the accessible
 72range will be bounced using the routines in arch/arm/common/dmabounce.c.
 73
 743b. Limited outbound PCI window
 75
 76IXP4xx provides two methods of accessing PCI memory space:
 77
 781) 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
 852) 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 disadvantage 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
 94By default, the direct method is used for performance reasons. If
 95you need more PCI memory, enable the IXP4XX_INDIRECT_PCI config option.
 96
 973c. GPIO as Interrupts
 98
 99Currently the code only handles level-sensitive GPIO interrupts
100
1014. Supported platforms
102
103ADI Engineering Coyote Gateway Reference Platform
104http://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
114Gateworks Avila Network Platform
115http://www.gateworks.com/support/overview.php
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
121Intel IXDP425 Development Platform
122http://www.intel.com/design/network/products/npfamily/ixdpg425.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
128Intel IXDP465 Development Platform
129http://www.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
134Intel 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
143Motorola PrPMC1100 Processor Mezanine Card
144http://www.fountainsys.com
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
1525. TODO LIST
153
154- Add support for Coyote IDE
155- Add support for edge-based GPIO interrupts
156- Add support for CF IDE on expansion bus
157
1586. Thanks
159
160The IXP4xx work has been funded by Intel Corp. and MontaVista Software, Inc.
161
162The following people have contributed patches/comments/etc:
163
164- Lennerty Buytenhek
165- Lutz Jaenicke
166- Justin Mayfield
167- Robert E. Ranslam
168
169[I know I've forgotten others, please email me to be added]
170
171-------------------------------------------------------------------------
172
173Last Update: 01/04/2005