From a4d1ca3425df99918a6c8af45a660c62687e2ced Mon Sep 17 00:00:00 2001 From: Nicolas Ferre Date: Tue, 6 Jan 2015 11:25:12 +0100 Subject: ARM: at91/Documentation: add a README for Atmel SoCs Add a README file to describe Atmel SoCs (aka AT91) support in Mainline Linux: - SoC list + datasheet web links - Basic but useful information - Device Tree conventions and Work In Progress statement. Signed-off-by: Nicolas Ferre Acked-by: Olof Johansson --- Documentation/arm/Atmel/README | 124 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 124 insertions(+) create mode 100644 Documentation/arm/Atmel/README (limited to 'Documentation/arm') diff --git a/Documentation/arm/Atmel/README b/Documentation/arm/Atmel/README new file mode 100644 index 000000000000..c53a19b4aab2 --- /dev/null +++ b/Documentation/arm/Atmel/README @@ -0,0 +1,124 @@ +ARM Atmel SoCs (aka AT91) +========================= + + +Introduction +------------ +This document gives useful information about the ARM Atmel SoCs that are +currently supported in Linux Mainline (you know, the one on kernel.org). + +It is important to note that the Atmel | SMART 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 Atmel product name. Anyway, files, directories, git trees, +git branches/tags and email subject always contain this "at91" sub-string. + + +AT91 SoCs +--------- +Documentation and detailled datasheet for each product are available on +the Atmel website: http://www.atmel.com. + + Flavors: + * ARM 920 based SoC + - at91rm9200 + + Datasheet + http://www.atmel.com/Images/doc1768.pdf + + * ARM 926 based SoCs + - at91sam9260 + + Datasheet + http://www.atmel.com/Images/doc6221.pdf + + - at91sam9xe + + Datasheet + http://www.atmel.com/Images/Atmel-6254-32-bit-ARM926EJ-S-Embedded-Microprocessor-SAM9XE_Datasheet.pdf + + - at91sam9261 + + Datasheet + http://www.atmel.com/Images/doc6062.pdf + + - at91sam9263 + + Datasheet + http://www.atmel.com/Images/Atmel_6249_32-bit-ARM926EJ-S-Microcontroller_SAM9263_Datasheet.pdf + + - at91sam9rl + + Datasheet + http://www.atmel.com/Images/doc6289.pdf + + - at91sam9g20 + + Datasheet + http://www.atmel.com/Images/doc6384.pdf + + - at91sam9g45 family + - at91sam9g45 + - at91sam9g46 + - at91sam9m10 + - at91sam9m11 (device superset) + + Datasheet + http://www.atmel.com/Images/Atmel-6437-32-bit-ARM926-Embedded-Microprocessor-SAM9M11_Datasheet.pdf + + - at91sam9x5 family (aka "The 5 series") + - at91sam9g15 + - at91sam9g25 + - at91sam9g35 + - at91sam9x25 + - at91sam9x35 + + Datasheet (can be considered as covering the whole family) + http://www.atmel.com/Images/Atmel_11055_32-bit-ARM926EJ-S-Microcontroller_SAM9X35_Datasheet.pdf + + - at91sam9n12 + + Datasheet + http://www.atmel.com/Images/Atmel_11063_32-bit-ARM926EJ-S-Microcontroller_SAM9N12CN11CN12_Datasheet.pdf + + * ARM Cortex-A5 based SoCs + - sama5d3 family + - sama5d31 + - sama5d33 + - sama5d34 + - sama5d35 + - sama5d36 (device superset) + + Datasheet + http://www.atmel.com/Images/Atmel-11121-32-bit-Cortex-A5-Microcontroller-SAMA5D3_Datasheet.pdf + + * ARM Cortex-A5 + NEON based SoCs + - sama5d4 family + - sama5d41 + - sama5d42 + - sama5d43 + - sama5d44 (device superset) + + Datasheet + http://www.atmel.com/Images/Atmel-11238-32-bit-Cortex-A5-Microcontroller-SAMA5D4_Datasheet.pdf + + +Linux kernel information +------------------------ +Linux kernel mach directory: arch/arm/mach-at91 +MAINTAINERS entry is: "ARM/ATMEL AT91RM9200 AND AT91SAM ARM ARCHITECTURES" + + +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 Documentation/devicetree/bindings/ABI.txt 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). -- cgit v1.2.3