summaryrefslogtreecommitdiff
path: root/UefiCpuPkg
diff options
context:
space:
mode:
Diffstat (limited to 'UefiCpuPkg')
-rw-r--r--UefiCpuPkg/CpuDxe/CpuMp.c51
-rw-r--r--UefiCpuPkg/CpuDxe/CpuMp.h43
2 files changed, 93 insertions, 1 deletions
diff --git a/UefiCpuPkg/CpuDxe/CpuMp.c b/UefiCpuPkg/CpuDxe/CpuMp.c
index b576d18ca4..878cdf25db 100644
--- a/UefiCpuPkg/CpuDxe/CpuMp.c
+++ b/UefiCpuPkg/CpuDxe/CpuMp.c
@@ -30,7 +30,7 @@ EFI_MP_SERVICES_PROTOCOL mMpServicesTemplate = {
GetProcessorInfo,
StartupAllAPs,
StartupThisAP,
- NULL, // SwitchBSP,
+ SwitchBSP,
EnableDisableAP,
WhoAmI
};
@@ -892,6 +892,55 @@ StartupThisAP (
}
/**
+ This service switches the requested AP to be the BSP from that point onward.
+ This service changes the BSP for all purposes. This call can only be performed
+ by the current BSP.
+
+ This service switches the requested AP to be the BSP from that point onward.
+ This service changes the BSP for all purposes. The new BSP can take over the
+ execution of the old BSP and continue seamlessly from where the old one left
+ off. This service may not be supported after the UEFI Event EFI_EVENT_GROUP_READY_TO_BOOT
+ is signaled.
+
+ If the BSP cannot be switched prior to the return from this service, then
+ EFI_UNSUPPORTED must be returned.
+
+ @param[in] This A pointer to the EFI_MP_SERVICES_PROTOCOL instance.
+ @param[in] ProcessorNumber The handle number of AP that is to become the new
+ BSP. The range is from 0 to the total number of
+ logical processors minus 1. The total number of
+ logical processors can be retrieved by
+ EFI_MP_SERVICES_PROTOCOL.GetNumberOfProcessors().
+ @param[in] EnableOldBSP If TRUE, then the old BSP will be listed as an
+ enabled AP. Otherwise, it will be disabled.
+
+ @retval EFI_SUCCESS BSP successfully switched.
+ @retval EFI_UNSUPPORTED Switching the BSP cannot be completed prior to
+ this service returning.
+ @retval EFI_UNSUPPORTED Switching the BSP is not supported.
+ @retval EFI_SUCCESS The calling processor is an AP.
+ @retval EFI_NOT_FOUND The processor with the handle specified by
+ ProcessorNumber does not exist.
+ @retval EFI_INVALID_PARAMETER ProcessorNumber specifies the current BSP or
+ a disabled AP.
+ @retval EFI_NOT_READY The specified AP is busy.
+
+**/
+EFI_STATUS
+EFIAPI
+SwitchBSP (
+ IN EFI_MP_SERVICES_PROTOCOL *This,
+ IN UINTN ProcessorNumber,
+ IN BOOLEAN EnableOldBSP
+ )
+{
+ //
+ // Current always return unsupported.
+ //
+ return EFI_UNSUPPORTED;
+}
+
+/**
This service lets the caller enable or disable an AP from this point onward.
This service may only be called from the BSP.
diff --git a/UefiCpuPkg/CpuDxe/CpuMp.h b/UefiCpuPkg/CpuDxe/CpuMp.h
index 2b3b9b23d4..a53ef52d93 100644
--- a/UefiCpuPkg/CpuDxe/CpuMp.h
+++ b/UefiCpuPkg/CpuDxe/CpuMp.h
@@ -466,6 +466,49 @@ StartupThisAP (
);
/**
+ This service switches the requested AP to be the BSP from that point onward.
+ This service changes the BSP for all purposes. This call can only be performed
+ by the current BSP.
+
+ This service switches the requested AP to be the BSP from that point onward.
+ This service changes the BSP for all purposes. The new BSP can take over the
+ execution of the old BSP and continue seamlessly from where the old one left
+ off. This service may not be supported after the UEFI Event EFI_EVENT_GROUP_READY_TO_BOOT
+ is signaled.
+
+ If the BSP cannot be switched prior to the return from this service, then
+ EFI_UNSUPPORTED must be returned.
+
+ @param[in] This A pointer to the EFI_MP_SERVICES_PROTOCOL instance.
+ @param[in] ProcessorNumber The handle number of AP that is to become the new
+ BSP. The range is from 0 to the total number of
+ logical processors minus 1. The total number of
+ logical processors can be retrieved by
+ EFI_MP_SERVICES_PROTOCOL.GetNumberOfProcessors().
+ @param[in] EnableOldBSP If TRUE, then the old BSP will be listed as an
+ enabled AP. Otherwise, it will be disabled.
+
+ @retval EFI_SUCCESS BSP successfully switched.
+ @retval EFI_UNSUPPORTED Switching the BSP cannot be completed prior to
+ this service returning.
+ @retval EFI_UNSUPPORTED Switching the BSP is not supported.
+ @retval EFI_SUCCESS The calling processor is an AP.
+ @retval EFI_NOT_FOUND The processor with the handle specified by
+ ProcessorNumber does not exist.
+ @retval EFI_INVALID_PARAMETER ProcessorNumber specifies the current BSP or
+ a disabled AP.
+ @retval EFI_NOT_READY The specified AP is busy.
+
+**/
+EFI_STATUS
+EFIAPI
+SwitchBSP (
+ IN EFI_MP_SERVICES_PROTOCOL *This,
+ IN UINTN ProcessorNumber,
+ IN BOOLEAN EnableOldBSP
+ );
+
+/**
This service lets the caller enable or disable an AP from this point onward.
This service may only be called from the BSP.