dt-bindings: Document MIPS Broadcom STB power management nodes

Document the different nodes required for supporting S2/S3/S5 suspend
states on MIPS-based Broadcom STB SoCs.

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
This commit is contained in:
Florian Fainelli 2017-06-15 15:19:02 -07:00
parent 0b741b8234
commit dedcf233ce

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@ -11,3 +11,156 @@ Required properties:
The experimental -viper variants are for running Linux on the 3384's
BMIPS4355 cable modem CPU instead of the BMIPS5000 application processor.
Power management
----------------
For power management (particularly, S2/S3/S5 system suspend), the following SoC
components are needed:
= Always-On control block (AON CTRL)
This hardware provides control registers for the "always-on" (even in low-power
modes) hardware, such as the Power Management State Machine (PMSM).
Required properties:
- compatible : should be one of
"brcm,bcm7425-aon-ctrl"
"brcm,bcm7429-aon-ctrl"
"brcm,bcm7435-aon-ctrl" and
"brcm,brcmstb-aon-ctrl"
- reg : the register start and length for the AON CTRL block
Example:
syscon@410000 {
compatible = "brcm,bcm7425-aon-ctrl", "brcm,brcmstb-aon-ctrl";
reg = <0x410000 0x400>;
};
= Memory controllers
A Broadcom STB SoC typically has a number of independent memory controllers,
each of which may have several associated hardware blocks, which are versioned
independently (control registers, DDR PHYs, etc.). One might consider
describing these controllers as a parent "memory controllers" block, which
contains N sub-nodes (one for each controller in the system), each of which is
associated with a number of hardware register resources (e.g., its PHY.
== MEMC (MEMory Controller)
Represents a single memory controller instance.
Required properties:
- compatible : should contain "brcm,brcmstb-memc" and "simple-bus"
- ranges : should contain the child address in the parent address
space, must be 0 here, and the register start and length of
the entire memory controller (including all sub nodes: DDR PHY,
arbiter, etc.)
- #address-cells : must be 1
- #size-cells : must be 1
Example:
memory-controller@0 {
compatible = "brcm,brcmstb-memc", "simple-bus";
ranges = <0x0 0x0 0xa000>;
#address-cells = <1>;
#size-cells = <1>;
memc-arb@1000 {
...
};
memc-ddr@2000 {
...
};
ddr-phy@6000 {
...
};
};
Should contain subnodes for any of the following relevant hardware resources:
== DDR PHY control
Control registers for this memory controller's DDR PHY.
Required properties:
- compatible : should contain one of these
"brcm,brcmstb-ddr-phy-v64.5"
"brcm,brcmstb-ddr-phy"
- reg : the DDR PHY register range and length
Example:
ddr-phy@6000 {
compatible = "brcm,brcmstb-ddr-phy-v64.5";
reg = <0x6000 0xc8>;
};
== DDR memory controller sequencer
Control registers for this memory controller's DDR memory sequencer
Required properties:
- compatible : should contain one of these
"brcm,bcm7425-memc-ddr"
"brcm,bcm7429-memc-ddr"
"brcm,bcm7435-memc-ddr" and
"brcm,brcmstb-memc-ddr"
- reg : the DDR sequencer register range and length
Example:
memc-ddr@2000 {
compatible = "brcm,bcm7425-memc-ddr", "brcm,brcmstb-memc-ddr";
reg = <0x2000 0x300>;
};
== MEMC Arbiter
The memory controller arbiter is responsible for memory clients allocation
(bandwidth, priorities etc.) and needs to have its contents restored during
deep sleep states (S3).
Required properties:
- compatible : should contain one of these
"brcm,brcmstb-memc-arb-v10.0.0.0"
"brcm,brcmstb-memc-arb"
- reg : the DDR Arbiter register range and length
Example:
memc-arb@1000 {
compatible = "brcm,brcmstb-memc-arb-v10.0.0.0";
reg = <0x1000 0x248>;
};
== Timers
The Broadcom STB chips contain a timer block with several general purpose
timers that can be used.
Required properties:
- compatible : should contain one of:
"brcm,bcm7425-timers"
"brcm,bcm7429-timers"
"brcm,bcm7435-timers and
"brcm,brcmstb-timers"
- reg : the timers register range
- interrupts : the interrupt line for this timer block
Example:
timers: timer@4067c0 {
compatible = "brcm,bcm7425-timers", "brcm,brcmstb-timers";
reg = <0x4067c0 0x40>;
interrupts = <&periph_intc 19>;
};