Re: [PATCH] ArmPkg/ArmScmiDxe: Add clock enable function

[Leif Lindholm <leif.lindholm@linaro.org>]

Hi Jeff,

On Thu, Nov 08, 2018 at 10:50:44AM -0700, Jeff Brasen wrote:
> Add function to allow enabling and disabling of the clock using the SCMI
> interface. Update the protocol GUID as the protocol interface has
> changed.

Changing a protocol GUID for an interface update feels a bit
un-idiomatic for tianocore. (Generally, a new version of the protocol
is added.)

My main concern is that I can't see how removing the ability to
discover the protocol by the old GUID could ever have a desirable
outcome.

Girish, Sami, what's your take?

> 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(-)

Could you make sure you follow
https://github.com/tianocore/tianocore.github.io/wiki/Laszlo's-unkempt-git-guide-for-edk2-contributors-and-maintainers#contrib-23
when generating patches (or let os know if you are, and we have more
git breakage)?

/
    Leif

> 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
>