diff options
Diffstat (limited to 'Silicon/BroxtonSoC/BroxtonSiPkg/SouthCluster/SampleCode/BiosWriteProtect/Smm/ScBiosWriteProtect.c')
| -rw-r--r-- | Silicon/BroxtonSoC/BroxtonSiPkg/SouthCluster/SampleCode/BiosWriteProtect/Smm/ScBiosWriteProtect.c | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/Silicon/BroxtonSoC/BroxtonSiPkg/SouthCluster/SampleCode/BiosWriteProtect/Smm/ScBiosWriteProtect.c b/Silicon/BroxtonSoC/BroxtonSiPkg/SouthCluster/SampleCode/BiosWriteProtect/Smm/ScBiosWriteProtect.c new file mode 100644 index 0000000000..87dbf9c72b --- /dev/null +++ b/Silicon/BroxtonSoC/BroxtonSiPkg/SouthCluster/SampleCode/BiosWriteProtect/Smm/ScBiosWriteProtect.c @@ -0,0 +1,167 @@ +/** @file
+ SC BIOS Write Protect Driver.
+
+ Copyright (c) 2011 - 2016, Intel Corporation. All rights reserved.<BR>
+
+ This program and the accompanying materials
+ are licensed and made available under the terms and conditions of the BSD License
+ which accompanies this distribution. The full text of the license may be found at
+ http://opensource.org/licenses/bsd-license.php.
+
+ THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "ScBiosWriteProtect.h"
+
+//
+// Global variables
+//
+EFI_SMM_ICHN_DISPATCH_PROTOCOL *mIchnDispatch;
+EFI_SMM_SW_DISPATCH2_PROTOCOL *mSwDispatch;
+UINTN mPciSpiRegBase;
+
+/**
+ This hardware SMI handler will be run every time the BIOS Write Enable bit is set.
+
+ @param[in] DispatchHandle Not used
+ @param[in] DispatchContext Not used
+
+ @retval None
+
+**/
+VOID
+EFIAPI
+ScBiosWpCallback (
+ IN EFI_HANDLE DispatchHandle,
+ IN EFI_SMM_ICHN_DISPATCH_CONTEXT *DispatchContext
+ )
+{
+
+ //
+ // Disable BIOSWE bit to protect BIOS
+ //
+ MmioAnd8 ((UINTN) (mPciSpiRegBase + R_SPI_BCR), (UINT8) ~B_SPI_BCR_BIOSWE);
+
+ //
+ // Clear Sync SMI Status
+ //
+ MmioOr16 ((UINTN) (mPciSpiRegBase + R_SPI_BCR), (UINT16) B_SPI_BCR_SYNC_SS);
+}
+
+
+/**
+ Register an IchnBiosWp callback function to handle TCO BIOSWR SMI
+ SMM_BWP and BLE bits will be set here
+
+ @param[in] DispatchHandle Not used
+ @param[in] DispatchContext Not used
+
+ @retval None
+
+**/
+VOID
+EFIAPI
+ScBiosLockSwSmiCallback (
+ IN EFI_HANDLE DispatchHandle,
+ IN EFI_SMM_SW_REGISTER_CONTEXT *DispatchContext
+ )
+{
+ EFI_STATUS Status;
+ EFI_SMM_ICHN_DISPATCH_CONTEXT IchnContext;
+ EFI_HANDLE IchnHandle;
+
+ if (mIchnDispatch == NULL) {
+ return;
+ }
+
+ IchnHandle = NULL;
+
+ //
+ // Set SMM_BWP bit before registering IchnBiosWp
+ //
+ MmioOr8 ((UINTN) (mPciSpiRegBase + R_SPI_BCR), (UINT8) B_SPI_BCR_SMM_BWP);
+
+ //
+ // Register an IchnBiosWp callback function to handle TCO BIOSWR SMI
+ //
+ IchnContext.Type = IchnBiosWp;
+ Status = mIchnDispatch->Register (
+ mIchnDispatch,
+ ScBiosWpCallback,
+ &IchnContext,
+ &IchnHandle
+ );
+ ASSERT_EFI_ERROR (Status);
+}
+
+
+/**
+ Entry point for SC Bios Write Protect driver.
+
+ @param[in] ImageHandle Image handle of this driver.
+ @param[in] SystemTable Global system service table.
+
+ @retval EFI_SUCCESS Initialization complete.
+
+**/
+EFI_STATUS
+EFIAPI
+InstallScBiosWriteProtect (
+ IN EFI_HANDLE ImageHandle,
+ IN EFI_SYSTEM_TABLE *SystemTable
+ )
+{
+ EFI_STATUS Status;
+ SC_POLICY_HOB *ScPolicy;
+ EFI_HANDLE SwHandle;
+ EFI_SMM_SW_REGISTER_CONTEXT SwContext;
+ EFI_PEI_HOB_POINTERS HobPtr;
+ SC_LOCK_DOWN_CONFIG *LockDownConfig;
+
+ //
+ // Get Sc Platform Policy Hob
+ //
+ HobPtr.Guid = GetFirstGuidHob (&gScPolicyHobGuid);
+ ASSERT (HobPtr.Guid != NULL);
+ ScPolicy = (SC_POLICY_HOB *) GET_GUID_HOB_DATA (HobPtr.Guid);
+ Status = GetConfigBlock ((VOID *) ScPolicy, &gLockDownConfigGuid, (VOID *) &LockDownConfig);
+ ASSERT_EFI_ERROR (Status);
+
+ if ((LockDownConfig->BiosLock == TRUE)) {
+ mPciSpiRegBase = MmPciBase (
+ DEFAULT_PCI_BUS_NUMBER_SC,
+ PCI_DEVICE_NUMBER_SPI,
+ PCI_FUNCTION_NUMBER_SPI
+ );
+ //
+ // Get the ICHn protocol
+ //
+ mIchnDispatch = NULL;
+ Status = gSmst->SmmLocateProtocol (&gEfiSmmIchnDispatchProtocolGuid, NULL, (VOID **) &mIchnDispatch);
+ ASSERT_EFI_ERROR (Status);
+
+ //
+ // Locate the SC SMM SW dispatch protocol
+ //
+ SwHandle = NULL;
+ Status = gSmst->SmmLocateProtocol (&gEfiSmmSwDispatch2ProtocolGuid, NULL, (VOID **) &mSwDispatch);
+ ASSERT_EFI_ERROR (Status);
+
+ //
+ // Register BIOS Lock SW SMI handler
+ //
+ SwContext.SwSmiInputValue = LockDownConfig->BiosLockSwSmiNumber;
+ Status = mSwDispatch->Register (
+ mSwDispatch,
+ (EFI_SMM_HANDLER_ENTRY_POINT2) ScBiosLockSwSmiCallback,
+ &SwContext,
+ &SwHandle
+ );
+ ASSERT_EFI_ERROR (Status);
+ }
+
+ return EFI_SUCCESS;
+}
+
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