[PATCH v4] dt: update PSCI binding documentation for v0.2

[robherring2@gmail.com (Rob Herring)]

From: Rob Herring <rob.herring@calxeda.com>

The PSCI spec from ARM has been updated to 0.2 version. Update the
binding document to reflect the spec changes. For the binding, the
major changes are the addition of psci_version, affinity_info,
migrate_info_type, migrate_info_up_cpu, system_reset and system_off
functions. The recommended function ID numbering has also changed.

This update also defines 32 and 64 bit calling conventions. The calling
convention is defined on a per function ID basis.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Dave Martin <Dave.Martin@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ian Campbell <Ian.Campbell@citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Marc Zyngier <Marc.Zyngier@arm.com>
Cc: Christoffer Dall <christoffer.dall@linaro.org>,
Cc: Charles Garcia-Tobin <Charles.Garcia-Tobin@arm.com>
Cc: Matt Sealey <neko@bakuhatsu.net>
Cc: devicetree at vger.kernel.org
---
v4: Reword last paragraph concerning calling convention used for
functions without -32 or -64 suffix.

v3: This version implements Mark's suggested binding with -32 and -64
 suffixes.

 Documentation/devicetree/bindings/arm/psci.txt | 64 +++++++++++++++++++-------
 1 file changed, 48 insertions(+), 16 deletions(-)

diff --git a/Documentation/devicetree/bindings/arm/psci.txt b/Documentation/devicetree/bindings/arm/psci.txt
index 433afe9..8675ec2 100644
--- a/Documentation/devicetree/bindings/arm/psci.txt
+++ b/Documentation/devicetree/bindings/arm/psci.txt
@@ -1,16 +1,17 @@
 * Power State Coordination Interface (PSCI)
 
 Firmware implementing the PSCI functions described in ARM document number
-ARM DEN 0022A ("Power State Coordination Interface System Software on ARM
+ARM DEN 0022B ("Power State Coordination Interface System Software on ARM
 processors") can be used by Linux to initiate various CPU-centric power
 operations.
 
-Issue A of the specification describes functions for CPU suspend, hotplug
-and migration of secure software.
+Issue B of the specification describes functions for CPU suspend, hotplug,
+migration of secure software, and system level reset and powerdown.
 
 Functions are invoked by trapping to the privilege level of the PSCI
 firmware (specified as part of the binding below) and passing arguments
-in a manner similar to that specified by AAPCS:
+as defined in ARM document "SMC Calling Convention" (ARM DEN 0028) in a manner
+similar to that specified by AAPCS:
 
 	 r0		=> 32-bit Function ID / return value
 	{r1 - r3}	=> Parameters
@@ -21,10 +22,10 @@ to #0.
 
 Main node required properties:
 
- - compatible    : Must be "arm,psci"
+ - compatible    : Must contain "arm,psci-0.2" or "arm,psci"
 
- - method        : The method of calling the PSCI firmware. Permitted
-                   values are:
+ - method        : The method defines the calling convention for the PSCI
+                   firmware. Permitted values are:
 
                    "smc" : SMC #0, with the register assignments specified
 		           in this binding.
@@ -32,24 +33,55 @@ Main node required properties:
                    "hvc" : HVC #0, with the register assignments specified
 		           in this binding.
 
+ - psci_version  : Function ID for PSCI_VERSION operation. Required for
+                   "arm,psci-0.2" compatible version or later.
+
 Main node optional properties:
 
- - cpu_suspend   : Function ID for CPU_SUSPEND operation
+ - cpu_suspend[-<32|64]   : Function ID for CPU_SUSPEND operation
+
+ - cpu_off                : Function ID for CPU_OFF operation
+
+ - cpu_on[-<32|64]        : Function ID for CPU_ON operation
+
+ - affinity_info[-<32|64] : Function ID for AFFINITY_INFO operation
 
- - cpu_off       : Function ID for CPU_OFF operation
+ - migrate[-<32|64]       : Function ID for MIGRATE operation
 
- - cpu_on        : Function ID for CPU_ON operation
+ - migrate_info_type      : Function ID for MIGRATE_INFO_TYPE operation
 
- - migrate       : Function ID for MIGRATE operation
+ - migrate_info_up_cpu[-<32|64] : Function ID for MIGRATE_INFO_UP_CPU operation
 
+ - system_reset           : Function ID for SYSTEM_RESET operation
+
+ - system_off             : Function ID for SYSTEM_OFF operation
+
+Some functions have have separate IDs for 32-bit and 64-bit calling
+conventions. These separate function IDs are described with function names with
+"-64" and "-32" suffixes (e.g. cpu_on-64). Where a function name does not have
+a suffix, the ID may be used with either calling convention depending on the
+CPU state -- AArch32 callers should use the 32-bit calling convention, and
+AArch64 callers should use the 64-bit calling convention.
 
 Example:
 
 	psci {
-		compatible	= "arm,psci";
+		compatible	= "arm,psci-0.2";
 		method		= "smc";
-		cpu_suspend	= <0x95c10000>;
-		cpu_off		= <0x95c10001>;
-		cpu_on		= <0x95c10002>;
-		migrate		= <0x95c10003>;
+		psci_version	= <0x84000000>;
+		cpu_suspend-32	= <0x84000001>;
+		cpu_suspend-64	= <0xc4000001>;
+		cpu_off		= <0x84000002>;
+		cpu_on-32	= <0x84000003>;
+		cpu_on-64	= <0xc4000003>;
+		affinity_info-32 = <0x84000004>;
+		affinity_info-64 = <0xc4000004>;
+		migrate-32	= <0x84000005>;
+		migrate-64	= <0xc4000005>;
+		migrate_info_type = <0x84000006>;
+		migrate_info_up_cpu-32 = <0x84000007>;
+		migrate_info_up_cpu-64 = <0xc4000007>;
+		system_off	= <0x84000008>;
+		system_reset	= <0x84000009>;
 	};
+
-- 
1.8.1.2