drivers: firmware: psci: add extended stateid power_state support

PSCI v1.0 augmented the power_state parameter format specification
(extended stateid) and introduced a way to probe it through the
PSCI_FEATURES interface.

This patch implements code that detects the power_state format at
run-time through the PSCI_FEATURES interface, so that the power_state
argument can be properly detected and validated in the kernel according
to the information provided through firmware.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Jisheng Zhang <jszhang@marvell.com>
Cc: Mark Rutland <mark.rutland@arm.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/include/uapi/linux/psci.h b/include/uapi/linux/psci.h
index 187b828d77b3..0a9485f3c6c3 100644
--- a/include/uapi/linux/psci.h
+++ b/include/uapi/linux/psci.h
@@ -58,6 +58,13 @@
 #define PSCI_0_2_POWER_STATE_AFFL_MASK          \
                                 (0x3 << PSCI_0_2_POWER_STATE_AFFL_SHIFT)
 
+/* PSCI extended power state encoding for CPU_SUSPEND function */
+#define PSCI_1_0_EXT_POWER_STATE_ID_MASK        0xfffffff
+#define PSCI_1_0_EXT_POWER_STATE_ID_SHIFT       0
+#define PSCI_1_0_EXT_POWER_STATE_TYPE_SHIFT     30
+#define PSCI_1_0_EXT_POWER_STATE_TYPE_MASK      \
+                                (0x1 << PSCI_1_0_EXT_POWER_STATE_TYPE_SHIFT)
+
 /* PSCI v0.2 affinity level state returned by AFFINITY_INFO */
 #define PSCI_0_2_AFFINITY_LEVEL_ON              0
 #define PSCI_0_2_AFFINITY_LEVEL_OFF             1
@@ -78,6 +85,11 @@
 #define PSCI_VERSION_MINOR(ver)                 \
                 ((ver) & PSCI_VERSION_MINOR_MASK)
 
+/* PSCI features decoding (>=1.0) */
+#define PSCI_1_0_FEATURES_CPU_SUSPEND_PF_SHIFT  1
+#define PSCI_1_0_FEATURES_CPU_SUSPEND_PF_MASK   \
+                        (0x1 << PSCI_1_0_FEATURES_CPU_SUSPEND_PF_SHIFT)
+
 /* PSCI return values (inclusive of all PSCI versions) */
 #define PSCI_RET_SUCCESS                        0
 #define PSCI_RET_NOT_SUPPORTED                  -1