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diff --git a/Documentation/powerpc/dts-bindings/fsl/mpic.txt b/Documentation/powerpc/dts-bindings/fsl/mpic.txt deleted file mode 100644 index 71e39cf3215..00000000000 --- a/Documentation/powerpc/dts-bindings/fsl/mpic.txt +++ /dev/null @@ -1,42 +0,0 @@ -* OpenPIC and its interrupt numbers on Freescale's e500/e600 cores - -The OpenPIC specification does not specify which interrupt source has to -become which interrupt number. This is up to the software implementation -of the interrupt controller. The only requirement is that every -interrupt source has to have an unique interrupt number / vector number. -To accomplish this the current implementation assigns the number zero to -the first source, the number one to the second source and so on until -all interrupt sources have their unique number. -Usually the assigned vector number equals the interrupt number mentioned -in the documentation for a given core / CPU. This is however not true -for the e500 cores (MPC85XX CPUs) where the documentation distinguishes -between internal and external interrupt sources and starts counting at -zero for both of them. - -So what to write for external interrupt source X or internal interrupt -source Y into the device tree? Here is an example: - -The memory map for the interrupt controller in the MPC8544[0] shows, -that the first interrupt source starts at 0x5_0000 (PIC Register Address -Map-Interrupt Source Configuration Registers). This source becomes the -number zero therefore: - External interrupt 0 = interrupt number 0 - External interrupt 1 = interrupt number 1 - External interrupt 2 = interrupt number 2 - ... -Every interrupt number allocates 0x20 bytes register space. So to get -its number it is sufficient to shift the lower 16bits to right by five. -So for the external interrupt 10 we have: - 0x0140 >> 5 = 10 - -After the external sources, the internal sources follow. The in core I2C -controller on the MPC8544 for instance has the internal source number -27. Oo obtain its interrupt number we take the lower 16bits of its memory -address (0x5_0560) and shift it right: - 0x0560 >> 5 = 43 - -Therefore the I2C device node for the MPC8544 CPU has to have the -interrupt number 43 specified in the device tree. - -[0] MPC8544E PowerQUICCTM III, Integrated Host Processor Family Reference Manual - MPC8544ERM Rev. 1 10/2007 |