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/*++
Copyright (c) 2009, Hewlett-Packard Company. All rights reserved.<BR>
Portions copyright (c) 2010, Apple Inc. All rights reserved.<BR>
Portions copyright (c) 2011-2013, ARM Ltd. All rights reserved.<BR>
Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
--*/
#include <Library/MemoryAllocationLib.h>
#include "CpuDxe.h"
#define TT_ATTR_INDX_INVALID ((UINT32)~0)
STATIC
UINT64
GetFirstPageAttribute (
IN UINT64 *FirstLevelTableAddress,
IN UINTN TableLevel
)
{
UINT64 FirstEntry;
// Get the first entry of the table
FirstEntry = *FirstLevelTableAddress;
if ((TableLevel != 3) && (FirstEntry & TT_TYPE_MASK) == TT_TYPE_TABLE_ENTRY) {
// Only valid for Levels 0, 1 and 2
// Get the attribute of the subsequent table
return GetFirstPageAttribute ((UINT64*)(FirstEntry & TT_ADDRESS_MASK_DESCRIPTION_TABLE), TableLevel + 1);
} else if (((FirstEntry & TT_TYPE_MASK) == TT_TYPE_BLOCK_ENTRY) ||
((TableLevel == 3) && ((FirstEntry & TT_TYPE_MASK) == TT_TYPE_BLOCK_ENTRY_LEVEL3)))
{
return FirstEntry & TT_ATTR_INDX_MASK;
} else {
return TT_ATTR_INDX_INVALID;
}
}
STATIC
UINT64
GetNextEntryAttribute (
IN UINT64 *TableAddress,
IN UINTN EntryCount,
IN UINTN TableLevel,
IN UINT64 BaseAddress,
IN OUT UINT32 *PrevEntryAttribute,
IN OUT UINT64 *StartGcdRegion
)
{
UINTN Index;
UINT64 Entry;
UINT32 EntryAttribute;
UINT32 EntryType;
EFI_STATUS Status;
UINTN NumberOfDescriptors;
EFI_GCD_MEMORY_SPACE_DESCRIPTOR *MemorySpaceMap;
// Get the memory space map from GCD
MemorySpaceMap = NULL;
Status = gDS->GetMemorySpaceMap (&NumberOfDescriptors, &MemorySpaceMap);
ASSERT_EFI_ERROR (Status);
// We cannot get more than 3-level page table
ASSERT (TableLevel <= 3);
// While the top level table might not contain TT_ENTRY_COUNT entries;
// the subsequent ones should be filled up
for (Index = 0; Index < EntryCount; Index++) {
Entry = TableAddress[Index];
EntryType = Entry & TT_TYPE_MASK;
EntryAttribute = Entry & TT_ATTR_INDX_MASK;
// If Entry is a Table Descriptor type entry then go through the sub-level table
if ((EntryType == TT_TYPE_BLOCK_ENTRY) ||
((TableLevel == 3) && (EntryType == TT_TYPE_BLOCK_ENTRY_LEVEL3))) {
if ((*PrevEntryAttribute == TT_ATTR_INDX_INVALID) || (EntryAttribute != *PrevEntryAttribute)) {
if (*PrevEntryAttribute != TT_ATTR_INDX_INVALID) {
// Update GCD with the last region
SetGcdMemorySpaceAttributes (MemorySpaceMap, NumberOfDescriptors,
*StartGcdRegion,
(BaseAddress + (Index * TT_ADDRESS_AT_LEVEL(TableLevel))) - *StartGcdRegion,
PageAttributeToGcdAttribute (*PrevEntryAttribute));
}
// Start of the new region
*StartGcdRegion = BaseAddress + (Index * TT_ADDRESS_AT_LEVEL(TableLevel));
*PrevEntryAttribute = EntryAttribute;
} else {
continue;
}
} else if (EntryType == TT_TYPE_TABLE_ENTRY) {
// Table Entry type is only valid for Level 0, 1, 2
ASSERT (TableLevel < 3);
// Increase the level number and scan the sub-level table
GetNextEntryAttribute ((UINT64*)(Entry & TT_ADDRESS_MASK_DESCRIPTION_TABLE),
TT_ENTRY_COUNT, TableLevel + 1,
(BaseAddress + (Index * TT_ADDRESS_AT_LEVEL(TableLevel))),
PrevEntryAttribute, StartGcdRegion);
} else {
if (*PrevEntryAttribute != TT_ATTR_INDX_INVALID) {
// Update GCD with the last region
SetGcdMemorySpaceAttributes (MemorySpaceMap, NumberOfDescriptors,
*StartGcdRegion,
(BaseAddress + (Index * TT_ADDRESS_AT_LEVEL(TableLevel))) - *StartGcdRegion,
PageAttributeToGcdAttribute (*PrevEntryAttribute));
// Start of the new region
*StartGcdRegion = BaseAddress + (Index * TT_ADDRESS_AT_LEVEL(TableLevel));
*PrevEntryAttribute = TT_ATTR_INDX_INVALID;
}
}
}
FreePool (MemorySpaceMap);
return BaseAddress + (EntryCount * TT_ADDRESS_AT_LEVEL(TableLevel));
}
EFI_STATUS
SyncCacheConfig (
IN EFI_CPU_ARCH_PROTOCOL *CpuProtocol
)
{
EFI_STATUS Status;
UINT32 PageAttribute = 0;
UINT64 *FirstLevelTableAddress;
UINTN TableLevel;
UINTN TableCount;
UINTN NumberOfDescriptors;
EFI_GCD_MEMORY_SPACE_DESCRIPTOR *MemorySpaceMap;
UINTN Tcr;
UINTN T0SZ;
UINT64 BaseAddressGcdRegion;
UINT64 EndAddressGcdRegion;
// This code assumes MMU is enabled and filed with section translations
ASSERT (ArmMmuEnabled ());
//
// Get the memory space map from GCD
//
MemorySpaceMap = NULL;
Status = gDS->GetMemorySpaceMap (&NumberOfDescriptors, &MemorySpaceMap);
ASSERT_EFI_ERROR (Status);
// The GCD implementation maintains its own copy of the state of memory space attributes. GCD needs
// to know what the initial memory space attributes are. The CPU Arch. Protocol does not provide a
// GetMemoryAttributes function for GCD to get this so we must resort to calling GCD (as if we were
// a client) to update its copy of the attributes. This is bad architecture and should be replaced
// with a way for GCD to query the CPU Arch. driver of the existing memory space attributes instead.
// Obtain page table base
FirstLevelTableAddress = (UINT64*)(ArmGetTTBR0BaseAddress ());
// Get Translation Control Register value
Tcr = ArmGetTCR ();
// Get Address Region Size
T0SZ = Tcr & TCR_T0SZ_MASK;
// Get the level of the first table for the indicated Address Region Size
GetRootTranslationTableInfo (T0SZ, &TableLevel, &TableCount);
// First Attribute of the Page Tables
PageAttribute = GetFirstPageAttribute (FirstLevelTableAddress, TableLevel);
// We scan from the start of the memory map (ie: at the address 0x0)
BaseAddressGcdRegion = 0x0;
EndAddressGcdRegion = GetNextEntryAttribute (FirstLevelTableAddress,
TableCount, TableLevel,
BaseAddressGcdRegion,
&PageAttribute, &BaseAddressGcdRegion);
// Update GCD with the last region if valid
if (PageAttribute != TT_ATTR_INDX_INVALID) {
SetGcdMemorySpaceAttributes (MemorySpaceMap, NumberOfDescriptors,
BaseAddressGcdRegion,
EndAddressGcdRegion - BaseAddressGcdRegion,
PageAttributeToGcdAttribute (PageAttribute));
}
FreePool (MemorySpaceMap);
return EFI_SUCCESS;
}
UINT64
EfiAttributeToArmAttribute (
IN UINT64 EfiAttributes
)
{
UINT64 ArmAttributes;
switch (EfiAttributes & EFI_MEMORY_CACHETYPE_MASK) {
case EFI_MEMORY_UC:
if (ArmReadCurrentEL () == AARCH64_EL2) {
ArmAttributes = TT_ATTR_INDX_DEVICE_MEMORY | TT_XN_MASK;
} else {
ArmAttributes = TT_ATTR_INDX_DEVICE_MEMORY | TT_UXN_MASK | TT_PXN_MASK;
}
break;
case EFI_MEMORY_WC:
ArmAttributes = TT_ATTR_INDX_MEMORY_NON_CACHEABLE;
break;
case EFI_MEMORY_WT:
ArmAttributes = TT_ATTR_INDX_MEMORY_WRITE_THROUGH | TT_SH_INNER_SHAREABLE;
break;
case EFI_MEMORY_WB:
ArmAttributes = TT_ATTR_INDX_MEMORY_WRITE_BACK | TT_SH_INNER_SHAREABLE;
break;
default:
ArmAttributes = TT_ATTR_INDX_MASK;
}
// Set the access flag to match the block attributes
ArmAttributes |= TT_AF;
// Determine protection attributes
if (EfiAttributes & EFI_MEMORY_RO) {
ArmAttributes |= TT_AP_RO_RO;
}
// Process eXecute Never attribute
if (EfiAttributes & EFI_MEMORY_XP) {
ArmAttributes |= TT_PXN_MASK;
}
return ArmAttributes;
}
// This function will recursively go down the page table to find the first block address linked to 'BaseAddress'.
// And then the function will identify the size of the region that has the same page table attribute.
EFI_STATUS
GetMemoryRegionRec (
IN UINT64 *TranslationTable,
IN UINTN TableLevel,
IN UINT64 *LastBlockEntry,
IN OUT UINTN *BaseAddress,
OUT UINTN *RegionLength,
OUT UINTN *RegionAttributes
)
{
EFI_STATUS Status;
UINT64 *NextTranslationTable;
UINT64 *BlockEntry;
UINT64 BlockEntryType;
UINT64 EntryType;
if (TableLevel != 3) {
BlockEntryType = TT_TYPE_BLOCK_ENTRY;
} else {
BlockEntryType = TT_TYPE_BLOCK_ENTRY_LEVEL3;
}
// Find the block entry linked to the Base Address
BlockEntry = (UINT64*)TT_GET_ENTRY_FOR_ADDRESS (TranslationTable, TableLevel, *BaseAddress);
EntryType = *BlockEntry & TT_TYPE_MASK;
if ((TableLevel < 3) && (EntryType == TT_TYPE_TABLE_ENTRY)) {
NextTranslationTable = (UINT64*)(*BlockEntry & TT_ADDRESS_MASK_DESCRIPTION_TABLE);
// The entry is a page table, so we go to the next level
Status = GetMemoryRegionRec (
NextTranslationTable, // Address of the next level page table
TableLevel + 1, // Next Page Table level
(UINTN*)TT_LAST_BLOCK_ADDRESS(NextTranslationTable, TT_ENTRY_COUNT),
BaseAddress, RegionLength, RegionAttributes);
// In case of 'Success', it means the end of the block region has been found into the upper
// level translation table
if (!EFI_ERROR(Status)) {
return EFI_SUCCESS;
}
// Now we processed the table move to the next entry
BlockEntry++;
} else if (EntryType == BlockEntryType) {
// We have found the BlockEntry attached to the address. We save its start address (the start
// address might be before the 'BaseAddress') and attributes
*BaseAddress = *BaseAddress & ~(TT_ADDRESS_AT_LEVEL(TableLevel) - 1);
*RegionLength = 0;
*RegionAttributes = *BlockEntry & TT_ATTRIBUTES_MASK;
} else {
// We have an 'Invalid' entry
return EFI_UNSUPPORTED;
}
while (BlockEntry <= LastBlockEntry) {
if ((*BlockEntry & TT_ATTRIBUTES_MASK) == *RegionAttributes) {
*RegionLength = *RegionLength + TT_BLOCK_ENTRY_SIZE_AT_LEVEL(TableLevel);
} else {
// In case we have found the end of the region we return success
return EFI_SUCCESS;
}
BlockEntry++;
}
// If we have reached the end of the TranslationTable and we have not found the end of the region then
// we return EFI_NOT_FOUND.
// The caller will continue to look for the memory region at its level
return EFI_NOT_FOUND;
}
EFI_STATUS
GetMemoryRegion (
IN OUT UINTN *BaseAddress,
OUT UINTN *RegionLength,
OUT UINTN *RegionAttributes
)
{
EFI_STATUS Status;
UINT64 *TranslationTable;
UINTN TableLevel;
UINTN EntryCount;
UINTN T0SZ;
ASSERT ((BaseAddress != NULL) && (RegionLength != NULL) && (RegionAttributes != NULL));
TranslationTable = ArmGetTTBR0BaseAddress ();
T0SZ = ArmGetTCR () & TCR_T0SZ_MASK;
// Get the Table info from T0SZ
GetRootTranslationTableInfo (T0SZ, &TableLevel, &EntryCount);
Status = GetMemoryRegionRec (TranslationTable, TableLevel,
(UINTN*)TT_LAST_BLOCK_ADDRESS(TranslationTable, EntryCount),
BaseAddress, RegionLength, RegionAttributes);
// If the region continues up to the end of the root table then GetMemoryRegionRec()
// will return EFI_NOT_FOUND
if (Status == EFI_NOT_FOUND) {
return EFI_SUCCESS;
} else {
return Status;
}
}
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