Commit 0fc197c7 authored by Lorenzo Pieralisi's avatar Lorenzo Pieralisi
Browse files

drivers: firmware: psci: add PSCI v1.0 DT bindings 



PSCI 1.0 is designed to be fully compliant to the PSCI 0.2
specification, with minor differences that are described in the
PSCI specification.

In particular, PSCI v1.0 augments the specification with a new
power_state format (extended stateid - probeable through the
PSCI_FEATURES call), changes some function return codes and
functions usage requirements wrt PSCI 0.2. These changes mean
that 1.0 vs 0.2 compliancy should be enforced through a DT
compatible string that allows firmware to specify 1.0 only
compliancy so that older kernels are prevented from using
PSCI 1.0 FW implementations in a non-compatible way (eg by
calling a 1.0 FW implementation and expecting 0.2 behaviour).

This patch adds PSCI 1.0 DT bindings and related compatible
string.

Signed-off-by: default avatarLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: default avatarSudeep Holla <sudeep.holla@arm.com>
Tested-by: default avatarJisheng Zhang <jszhang@marvell.com>
Cc: Mark Rutland <mark.rutland@arm.com>
parent a5c00bb2

Documentation/devicetree/bindings/arm/psci.txt

+6 −0
Original line number Original line Diff line number Diff line
@@ -31,6 +31,10 @@ Main node required properties: 
					support, but are permitted to be present for compatibility with

					support, but are permitted to be present for compatibility with

					existing software when "arm,psci" is later in the compatible list.

					existing software when "arm,psci" is later in the compatible list.





				* "arm,psci-1.0" : for implementations complying to PSCI 1.0. PSCI 1.0 is

					backward compatible with PSCI 0.2 with minor specification updates,

					as defined in the PSCI specification[2].



 - method        : The method of calling the PSCI firmware. Permitted

 - method        : The method of calling the PSCI firmware. Permitted

                   values are:

                   values are:
@@ -100,3 +104,5 @@ Case 3: PSCI v0.2 and PSCI v0.1. 




[1] Kernel documentation - ARM idle states bindings

[1] Kernel documentation - ARM idle states bindings

    Documentation/devicetree/bindings/arm/idle-states.txt

    Documentation/devicetree/bindings/arm/idle-states.txt

[2] Power State Coordination Interface (PSCI) specification

    http://infocenter.arm.com/help/topic/com.arm.doc.den0022c/DEN0022C_Power_State_Coordination_Interface.pdf

drivers/firmware/psci.c

+1 −0
Original line number Original line Diff line number Diff line
@@ -392,6 +392,7 @@ out_put_node: 
static const struct of_device_id const psci_of_match[] __initconst = {

static const struct of_device_id const psci_of_match[] __initconst = {

	{ .compatible = "arm,psci",	.data = psci_0_1_init},

	{ .compatible = "arm,psci",	.data = psci_0_1_init},

	{ .compatible = "arm,psci-0.2",	.data = psci_0_2_init},

	{ .compatible = "arm,psci-0.2",	.data = psci_0_2_init},

	{ .compatible = "arm,psci-1.0",	.data = psci_0_2_init},

	{},

	{},

};

};

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