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@@ -1,61 +1,22 @@
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-CAN Device Tree Bindings
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-------------------------
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-2011 Freescale Semiconductor, Inc.
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+Flexcan CAN contoller on Freescale's ARM and PowerPC system-on-a-chip (SOC).
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-fsl,flexcan-v1.0 nodes
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------------------------
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-In addition to the required compatible-, reg- and interrupt-properties, you can
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-also specify which clock source shall be used for the controller.
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+Required properties:
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-CPI Clock- Can Protocol Interface Clock
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- This CLK_SRC bit of CTRL(control register) selects the clock source to
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- the CAN Protocol Interface(CPI) to be either the peripheral clock
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- (driven by the PLL) or the crystal oscillator clock. The selected clock
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- is the one fed to the prescaler to generate the Serial Clock (Sclock).
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- The PRESDIV field of CTRL(control register) controls a prescaler that
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- generates the Serial Clock (Sclock), whose period defines the
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- time quantum used to compose the CAN waveform.
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+- compatible : Should be "fsl,<processor>-flexcan"
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-Can Engine Clock Source
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- There are two sources for CAN clock
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- - Platform Clock It represents the bus clock
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- - Oscillator Clock
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+ An implementation should also claim any of the following compatibles
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+ that it is fully backwards compatible with:
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- Peripheral Clock (PLL)
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- --------------
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- |
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- --------- -------------
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- | |CPI Clock | Prescaler | Sclock
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- | |---------------->| (1.. 256) |------------>
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- --------- -------------
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- | |
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- -------------- ---------------------CLK_SRC
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- Oscillator Clock
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+ - fsl,p1010-flexcan
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-- fsl,flexcan-clock-source : CAN Engine Clock Source.This property selects
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- the peripheral clock. PLL clock is fed to the
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- prescaler to generate the Serial Clock (Sclock).
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- Valid values are "oscillator" and "platform"
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- "oscillator": CAN engine clock source is oscillator clock.
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- "platform" The CAN engine clock source is the bus clock
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- (platform clock).
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+- reg : Offset and length of the register set for this device
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+- interrupts : Interrupt tuple for this device
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-- fsl,flexcan-clock-divider : for the reference and system clock, an additional
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- clock divider can be specified.
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-- clock-frequency: frequency required to calculate the bitrate for FlexCAN.
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+Example:
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-Note:
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- - v1.0 of flexcan-v1.0 represent the IP block version for P1010 SOC.
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- - P1010 does not have oscillator as the Clock Source.So the default
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- Clock Source is platform clock.
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-Examples:
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-
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- can0@1c000 {
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- compatible = "fsl,flexcan-v1.0";
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+ can@1c000 {
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+ compatible = "fsl,p1010-flexcan";
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reg = <0x1c000 0x1000>;
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interrupts = <48 0x2>;
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interrupt-parent = <&mpic>;
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- fsl,flexcan-clock-source = "platform";
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- fsl,flexcan-clock-divider = <2>;
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- clock-frequency = <fixed by u-boot>;
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};
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