[PATCH] ArmPkg/ArmScmiDxe: Add clock enable function

[Jeff Brasen <jbrasen@nvidia.com>]

Add function to allow enabling and disabling of the clock using the SCMI
interface. Update the protocol GUID as the protocol interface has
changed.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jeff Brasen <jbrasen@nvidia.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Grish Pathak <girish.pathak@arm.com>
---
 ArmPkg/ArmPkg.dec                                  |  2 +-
 .../ArmScmiDxe/ArmScmiClockProtocolPrivate.h       |  7 +++
 ArmPkg/Drivers/ArmScmiDxe/ScmiClockProtocol.c      | 50 +++++++++++++++++++++-
 ArmPkg/Include/Protocol/ArmScmiClockProtocol.h     | 21 ++++++++-
 4 files changed, 77 insertions(+), 3 deletions(-)

diff --git a/ArmPkg/ArmPkg.dec b/ArmPkg/ArmPkg.dec
index 84e57a0..a7b55a1 100644
--- a/ArmPkg/ArmPkg.dec
+++ b/ArmPkg/ArmPkg.dec
@@ -57,7 +57,7 @@
 
   ## Arm System Control and Management Interface(SCMI) Clock management protocol
   ## ArmPkg/Include/Protocol/ArmScmiClockProtocol.h
-  gArmScmiClockProtocolGuid = { 0x91ce67a8, 0xe0aa, 0x4012, { 0xb9, 0x9f, 0xb6, 0xfc, 0xf3, 0x4, 0x8e, 0xaa } }
+  gArmScmiClockProtocolGuid = { 0xb8d8caf2, 0x9e94, 0x462c, { 0xa8, 0x34, 0x6c, 0x99, 0xfc, 0x05, 0xef, 0xcf } }
 
   ## Arm System Control and Management Interface(SCMI) Clock management protocol
   ## ArmPkg/Include/Protocol/ArmScmiPerformanceProtocol.h
diff --git a/ArmPkg/Drivers/ArmScmiDxe/ArmScmiClockProtocolPrivate.h b/ArmPkg/Drivers/ArmScmiDxe/ArmScmiClockProtocolPrivate.h
index 0d1ec6f..c135bac 100644
--- a/ArmPkg/Drivers/ArmScmiDxe/ArmScmiClockProtocolPrivate.h
+++ b/ArmPkg/Drivers/ArmScmiDxe/ArmScmiClockProtocolPrivate.h
@@ -59,6 +59,13 @@ typedef struct {
   CLOCK_RATE_DWORD Rate;
 } CLOCK_RATE_SET_ATTRIBUTES;
 
+
+// Message parameters for CLOCK_CONFIG_SET command.
+typedef struct {
+  UINT32 ClockId;
+  UINT32 Attributes;
+} CLOCK_CONFIG_SET_ATTRIBUTES;
+
 //  if ClockAttr Bit[0] is set then clock device is enabled.
 #define CLOCK_ENABLE_MASK         0x1
 #define CLOCK_ENABLED(ClockAttr)  ((ClockAttr & CLOCK_ENABLE_MASK) == 1)
diff --git a/ArmPkg/Drivers/ArmScmiDxe/ScmiClockProtocol.c b/ArmPkg/Drivers/ArmScmiDxe/ScmiClockProtocol.c
index 64d2afa..493eb45 100644
--- a/ArmPkg/Drivers/ArmScmiDxe/ScmiClockProtocol.c
+++ b/ArmPkg/Drivers/ArmScmiDxe/ScmiClockProtocol.c
@@ -388,6 +388,53 @@ ClockRateSet (
   return Status;
 }
 
+/** Enable/Disable specified clock.
+
+  @param[in]  This        A Pointer to SCMI_CLOCK_PROTOCOL Instance.
+  @param[in]  ClockId     Identifier for the clock device.
+  @param[in]  Enable      TRUE to enable, FALSE to disable.
+
+  @retval EFI_SUCCESS          Clock enable/disable successful.
+  @retval EFI_DEVICE_ERROR     SCP returns an SCMI error.
+  @retval !(EFI_SUCCESS)       Other errors.
+**/
+STATIC
+EFI_STATUS
+ClockEnable (
+  IN SCMI_CLOCK_PROTOCOL  *This,
+  IN UINT32               ClockId,
+  IN BOOLEAN              Enable
+  )
+{
+  EFI_STATUS                  Status;
+  CLOCK_CONFIG_SET_ATTRIBUTES *ClockConfigSetAttributes;
+  SCMI_COMMAND                Cmd;
+  UINT32                      PayloadLength;
+
+  Status = ScmiCommandGetPayload ((UINT32**)&ClockConfigSetAttributes);
+  if (EFI_ERROR (Status)) {
+    return Status;
+  }
+
+  // Fill arguments for clock protocol command.
+  ClockConfigSetAttributes->ClockId    = ClockId;
+  ClockConfigSetAttributes->Attributes = Enable ? BIT0 : 0;
+
+  Cmd.ProtocolId = SCMI_PROTOCOL_ID_CLOCK;
+  Cmd.MessageId  = SCMI_MESSAGE_ID_CLOCK_CONFIG_SET;
+
+  PayloadLength = sizeof (CLOCK_CONFIG_SET_ATTRIBUTES);
+
+  // Execute and wait for response on a SCMI channel.
+  Status = ScmiCommandExecute (
+             &Cmd,
+             &PayloadLength,
+             NULL
+             );
+
+  return Status;
+}
+
 // Instance of the SCMI clock management protocol.
 STATIC CONST SCMI_CLOCK_PROTOCOL ScmiClockProtocol = {
   ClockGetVersion,
@@ -395,7 +442,8 @@ STATIC CONST SCMI_CLOCK_PROTOCOL ScmiClockProtocol = {
   ClockGetClockAttributes,
   ClockDescribeRates,
   ClockRateGet,
-  ClockRateSet
+  ClockRateSet,
+  ClockEnable
  };
 
 /** Initialize clock management protocol and install protocol on a given handle.
diff --git a/ArmPkg/Include/Protocol/ArmScmiClockProtocol.h b/ArmPkg/Include/Protocol/ArmScmiClockProtocol.h
index 3db26cb..d367f37 100644
--- a/ArmPkg/Include/Protocol/ArmScmiClockProtocol.h
+++ b/ArmPkg/Include/Protocol/ArmScmiClockProtocol.h
@@ -21,7 +21,7 @@
 #include <Protocol/ArmScmi.h>
 
 #define ARM_SCMI_CLOCK_PROTOCOL_GUID { \
-  0x91ce67a8, 0xe0aa, 0x4012, {0xb9, 0x9f, 0xb6, 0xfc, 0xf3, 0x4, 0x8e, 0xaa} \
+  0xb8d8caf2, 0x9e94, 0x462c, { 0xa8, 0x34, 0x6c, 0x99, 0xfc, 0x05, 0xef, 0xcf } \
   }
 
 extern EFI_GUID gArmScmiClockProtocolGuid;
@@ -205,6 +205,24 @@ EFI_STATUS
   IN UINT64               Rate
   );
 
+/** Enable/Disable specified clock.
+
+  @param[in]  This        A Pointer to SCMI_CLOCK_PROTOCOL Instance.
+  @param[in]  ClockId     Identifier for the clock device.
+  @param[in]  Enable      TRUE to enable, FALSE to disable.
+
+  @retval EFI_SUCCESS          Clock enable/disable successful.
+  @retval EFI_DEVICE_ERROR     SCP returns an SCMI error.
+  @retval !(EFI_SUCCESS)       Other errors.
+**/
+typedef
+EFI_STATUS
+(EFIAPI *SCMI_CLOCK_ENABLE) (
+  IN SCMI_CLOCK_PROTOCOL  *This,
+  IN UINT32               ClockId,
+  IN BOOLEAN              Enable
+  );
+
 typedef struct _SCMI_CLOCK_PROTOCOL {
   SCMI_CLOCK_GET_VERSION GetVersion;
   SCMI_CLOCK_GET_TOTAL_CLOCKS GetTotalClocks;
@@ -212,6 +230,7 @@ typedef struct _SCMI_CLOCK_PROTOCOL {
   SCMI_CLOCK_DESCRIBE_RATES DescribeRates;
   SCMI_CLOCK_RATE_GET RateGet;
   SCMI_CLOCK_RATE_SET RateSet;
+  SCMI_CLOCK_ENABLE Enable;
 } SCMI_CLOCK_PROTOCOL;
 
 #endif /* ARM_SCMI_CLOCK_PROTOCOL_H_ */
-- 
2.7.4