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-rw-r--r--Documentation/arm/sunxi/README61
-rw-r--r--Documentation/arm/sunxi/clocks.txt56
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diff --git a/Documentation/arm/sunxi/README b/Documentation/arm/sunxi/README
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+ARM Allwinner SoCs
+==================
+
+This document lists all the ARM Allwinner SoCs that are currently
+supported in mainline by the Linux kernel. This document will also
+provide links to documentation and/or datasheet for these SoCs.
+
+SunXi family
+------------
+ Linux kernel mach directory: arch/arm/mach-sunxi
+
+ Flavors:
+ * ARM926 based SoCs
+ - Allwinner F20 (sun3i)
+ + Not Supported
+
+ * ARM Cortex-A8 based SoCs
+ - Allwinner A10 (sun4i)
+ + Datasheet
+ http://dl.linux-sunxi.org/A10/A10%20Datasheet%20-%20v1.21%20%282012-04-06%29.pdf
+ + User Manual
+ http://dl.linux-sunxi.org/A10/A10%20User%20Manual%20-%20v1.20%20%282012-04-09%2c%20DECRYPTED%29.pdf
+
+ - Allwinner A10s (sun5i)
+ + Datasheet
+ http://dl.linux-sunxi.org/A10s/A10s%20Datasheet%20-%20v1.20%20%282012-03-27%29.pdf
+
+ - Allwinner A13 (sun5i)
+ + Datasheet
+ http://dl.linux-sunxi.org/A13/A13%20Datasheet%20-%20v1.12%20%282012-03-29%29.pdf
+ + User Manual
+ http://dl.linux-sunxi.org/A13/A13%20User%20Manual%20-%20v1.2%20%282013-01-08%29.pdf
+
+ * Dual ARM Cortex-A7 based SoCs
+ - Allwinner A20 (sun7i)
+ + User Manual
+ http://dl.linux-sunxi.org/A20/A20%20User%20Manual%202013-03-22.pdf
+
+ - Allwinner A23
+ + Datasheet
+ http://dl.linux-sunxi.org/A23/A23%20Datasheet%20V1.0%2020130830.pdf
+ + User Manual
+ http://dl.linux-sunxi.org/A23/A23%20User%20Manual%20V1.0%2020130830.pdf
+
+ * Quad ARM Cortex-A7 based SoCs
+ - Allwinner A31 (sun6i)
+ + Datasheet
+ http://dl.linux-sunxi.org/A31/A3x_release_document/A31/IC/A31%20datasheet%20V1.3%2020131106.pdf
+ + User Manual
+ http://dl.linux-sunxi.org/A31/A3x_release_document/A31/IC/A31%20user%20manual%20V1.1%2020130630.pdf
+
+ - Allwinner A31s (sun6i)
+ + Datasheet
+ http://dl.linux-sunxi.org/A31/A3x_release_document/A31s/IC/A31s%20datasheet%20V1.3%2020131106.pdf
+ + User Manual
+ http://dl.linux-sunxi.org/A31/A3x_release_document/A31s/IC/A31s%20User%20Manual%20%20V1.0%2020130322.pdf
+
+ * Quad ARM Cortex-A15, Quad ARM Cortex-A7 based SoCs
+ - Allwinner A80
+ + Datasheet
+ http://dl.linux-sunxi.org/A80/A80_Datasheet_Revision_1.0_0404.pdf
diff --git a/Documentation/arm/sunxi/clocks.txt b/Documentation/arm/sunxi/clocks.txt
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+Frequently asked questions about the sunxi clock system
+=======================================================
+
+This document contains useful bits of information that people tend to ask
+about the sunxi clock system, as well as accompanying ASCII art when adequate.
+
+Q: Why is the main 24MHz oscillator gatable? Wouldn't that break the
+ system?
+
+A: The 24MHz oscillator allows gating to save power. Indeed, if gated
+ carelessly the system would stop functioning, but with the right
+ steps, one can gate it and keep the system running. Consider this
+ simplified suspend example:
+
+ While the system is operational, you would see something like
+
+ 24MHz 32kHz
+ |
+ PLL1
+ \
+ \_ CPU Mux
+ |
+ [CPU]
+
+ When you are about to suspend, you switch the CPU Mux to the 32kHz
+ oscillator:
+
+ 24Mhz 32kHz
+ | |
+ PLL1 |
+ /
+ CPU Mux _/
+ |
+ [CPU]
+
+ Finally you can gate the main oscillator
+
+ 32kHz
+ |
+ |
+ /
+ CPU Mux _/
+ |
+ [CPU]
+
+Q: Were can I learn more about the sunxi clocks?
+
+A: The linux-sunxi wiki contains a page documenting the clock registers,
+ you can find it at
+
+ http://linux-sunxi.org/A10/CCM
+
+ The authoritative source for information at this time is the ccmu driver
+ released by Allwinner, you can find it at
+
+ https://github.com/linux-sunxi/linux-sunxi/tree/sunxi-3.0/arch/arm/mach-sun4i/clock/ccmu