ARM Microchip SoCs (aka AT91)¶
Introduction¶
This document gives useful information about the ARM Microchip SoCs that are currently supported in Linux Mainline (you know, the one on kernel.org).
It is important to note that the Microchip (previously Atmel) ARM-based MPU product line is historically named "AT91" or "at91" throughout the Linux kernel development process even if this product prefix has completely disappeared from the official Microchip product name. Anyway, files, directories, git trees, git branches/tags and email subject always contain this "at91" sub-string.
AT91 SoCs¶
Documentation and detailed datasheet for each product are available on the Microchip website: http://www.microchip.com.
- Flavors:
ARM 920 based SoC - at91rm9200
ARM 926 based SoCs - at91sam9260
at91sam9xe
at91sam9261
at91sam9263
at91sam9rl
at91sam9g20
at91sam9g45 family - at91sam9g45 - at91sam9g46 - at91sam9m10 - at91sam9m11 (device superset)
at91sam9x5 family (aka "The 5 series") - at91sam9g15 - at91sam9g25 - at91sam9g35 - at91sam9x25 - at91sam9x35
Datasheet (can be considered as covering the whole family)
at91sam9n12
sam9x60
ARM Cortex-A5 based SoCs - sama5d3 family
sama5d31
sama5d33
sama5d34
sama5d35
sama5d36 (device superset)
Datasheet
ARM Cortex-A5 + NEON based SoCs - sama5d4 family
sama5d41
sama5d42
sama5d43
sama5d44 (device superset)
Datasheet
http://ww1.microchip.com/downloads/en/DeviceDoc/60001525A.pdf
sama5d2 family
sama5d21
sama5d22
sama5d23
sama5d24
sama5d26
sama5d27 (device superset)
sama5d28 (device superset + environmental monitors)
Datasheet
http://ww1.microchip.com/downloads/en/DeviceDoc/DS60001476B.pdf
ARM Cortex-A7 based SoCs - sama7g5 family
sama7g51
sama7g52
sama7g53
sama7g54 (device superset)
Datasheet
Coming soon
lan966 family - lan9662 - lan9668
Datasheet
Coming soon
ARM Cortex-M7 MCUs - sams70 family
sams70j19
sams70j20
sams70j21
sams70n19
sams70n20
sams70n21
sams70q19
sams70q20
sams70q21
samv70 family
samv70j19
samv70j20
samv70n19
samv70n20
samv70q19
samv70q20
samv71 family
samv71j19
samv71j20
samv71j21
samv71n19
samv71n20
samv71n21
samv71q19
samv71q20
samv71q21
Datasheet
Linux kernel information¶
Linux kernel mach directory: arch/arm/mach-at91 MAINTAINERS entry is: "ARM/Microchip (AT91) SoC support"
Device Tree for AT91 SoCs and boards¶
All AT91 SoCs are converted to Device Tree. Since Linux 3.19, these products must use this method to boot the Linux kernel.
Work In Progress statement: Device Tree files and Device Tree bindings that apply to AT91 SoCs and boards are considered as "Unstable". To be completely clear, any at91 binding can change at any time. So, be sure to use a Device Tree Binary and a Kernel Image generated from the same source tree. Please refer to the Devicetree (DT) ABI file for a definition of a "Stable" binding/ABI. This statement will be removed by AT91 MAINTAINERS when appropriate.
Naming conventions and best practice:
SoCs Device Tree Source Include files are named after the official name of the product (at91sam9g20.dtsi or sama5d33.dtsi for instance).
Device Tree Source Include files (.dtsi) are used to collect common nodes that can be shared across SoCs or boards (sama5d3.dtsi or at91sam9x5cm.dtsi for instance). When collecting nodes for a particular peripheral or topic, the identifier have to be placed at the end of the file name, separated with a "_" (at91sam9x5_can.dtsi or sama5d3_gmac.dtsi for example).
board Device Tree Source files (.dts) are prefixed by the string "at91-" so that they can be identified easily. Note that some files are historical exceptions to this rule (sama5d3[13456]ek.dts, usb_a9g20.dts or animeo_ip.dts for example).