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;
}
}
STATIC
UINT64*
GetBlockEntryListFromAddress (
IN UINT64 *RootTable,
IN UINT64 RegionStart,
OUT UINTN *TableLevel,
IN OUT UINT64 *BlockEntrySize,
OUT UINT64 **LastBlockEntry
)
{
UINTN RootTableLevel;
UINTN RootTableEntryCount;
UINT64 *TranslationTable;
UINT64 *BlockEntry;
UINT64 *SubTableBlockEntry;
UINT64 BlockEntryAddress;
UINTN BaseAddressAlignment;
UINTN PageLevel;
UINTN Index;
UINTN IndexLevel;
UINTN T0SZ;
UINT64 Attributes;
UINT64 TableAttributes;
// Initialize variable
BlockEntry = NULL;
// Ensure the parameters are valid
if (!(TableLevel && BlockEntrySize && LastBlockEntry)) {
ASSERT_EFI_ERROR (EFI_INVALID_PARAMETER);
return NULL;
}
// Ensure the Region is aligned on 4KB boundary
if ((RegionStart & (SIZE_4KB - 1)) != 0) {
ASSERT_EFI_ERROR (EFI_INVALID_PARAMETER);
return NULL;
}
// Ensure the required size is aligned on 4KB boundary and not 0
if ((*BlockEntrySize & (SIZE_4KB - 1)) != 0 || *BlockEntrySize == 0) {
ASSERT_EFI_ERROR (EFI_INVALID_PARAMETER);
return NULL;
}
T0SZ = ArmGetTCR () & TCR_T0SZ_MASK;
// Get the Table info from T0SZ
GetRootTranslationTableInfo (T0SZ, &RootTableLevel, &RootTableEntryCount);
// If the start address is 0x0 then we use the size of the region to identify the alignment
if (RegionStart == 0) {
// Identify the highest possible alignment for the Region Size
BaseAddressAlignment = LowBitSet64 (*BlockEntrySize);
} else {
// Identify the highest possible alignment for the Base Address
BaseAddressAlignment = LowBitSet64 (RegionStart);
}
// Identify the Page Level the RegionStart must belong to. Note that PageLevel
// should be at least 1 since block translations are not supported at level 0
PageLevel = MAX (3 - ((BaseAddressAlignment - 12) / 9), 1);
// If the required size is smaller than the current block size then we need to go to the page below.
// The PageLevel was calculated on the Base Address alignment but did not take in account the alignment
// of the allocation size
while (*BlockEntrySize < TT_BLOCK_ENTRY_SIZE_AT_LEVEL (PageLevel)) {
// It does not fit so we need to go a page level above
PageLevel++;
}
//
// Get the Table Descriptor for the corresponding PageLevel. We need to decompose RegionStart to get appropriate entries
//
TranslationTable = RootTable;
for (IndexLevel = RootTableLevel; IndexLevel <= PageLevel; IndexLevel++) {
BlockEntry = (UINT64*)TT_GET_ENTRY_FOR_ADDRESS (TranslationTable, IndexLevel, RegionStart);
if ((IndexLevel != 3) && ((*BlockEntry & TT_TYPE_MASK) == TT_TYPE_TABLE_ENTRY)) {
// Go to the next table
TranslationTable = (UINT64*)(*BlockEntry & TT_ADDRESS_MASK_DESCRIPTION_TABLE);
// If we are at the last level then update the last level to next level
if (IndexLevel == PageLevel) {
// Enter the next level
PageLevel++;
}
} else if ((*BlockEntry & TT_TYPE_MASK) == TT_TYPE_BLOCK_ENTRY) {
// If we are not at the last level then we need to split this BlockEntry
if (IndexLevel != PageLevel) {
// Retrieve the attributes from the block entry
Attributes = *BlockEntry & TT_ATTRIBUTES_MASK;
// Convert the block entry attributes into Table descriptor attributes
TableAttributes = TT_TABLE_AP_NO_PERMISSION;
if (Attributes & TT_PXN_MASK) {
TableAttributes = TT_TABLE_PXN;
}
// XN maps to UXN in the EL1&0 translation regime
if (Attributes & TT_XN_MASK) {
TableAttributes = TT_TABLE_XN;
}
if (Attributes & TT_NS) {
TableAttributes = TT_TABLE_NS;
}
// Get the address corresponding at this entry
BlockEntryAddress = RegionStart;
BlockEntryAddress = BlockEntryAddress >> TT_ADDRESS_OFFSET_AT_LEVEL(IndexLevel);
// Shift back to right to set zero before the effective address
BlockEntryAddress = BlockEntryAddress << TT_ADDRESS_OFFSET_AT_LEVEL(IndexLevel);
// Set the correct entry type for the next page level
if ((IndexLevel + 1) == 3) {
Attributes |= TT_TYPE_BLOCK_ENTRY_LEVEL3;
} else {
Attributes |= TT_TYPE_BLOCK_ENTRY;
}
// Create a new translation table
TranslationTable = (UINT64*)AllocateAlignedPages (EFI_SIZE_TO_PAGES(TT_ENTRY_COUNT * sizeof(UINT64)), TT_ALIGNMENT_DESCRIPTION_TABLE);
if (TranslationTable == NULL) {
return NULL;
}
// Populate the newly created lower level table
SubTableBlockEntry = TranslationTable;
for (Index = 0; Index < TT_ENTRY_COUNT; Index++) {
*SubTableBlockEntry = Attributes | (BlockEntryAddress + (Index << TT_ADDRESS_OFFSET_AT_LEVEL(IndexLevel + 1)));
SubTableBlockEntry++;
}
// Fill the BlockEntry with the new TranslationTable
*BlockEntry = ((UINTN)TranslationTable & TT_ADDRESS_MASK_DESCRIPTION_TABLE) | TableAttributes | TT_TYPE_TABLE_ENTRY;
}
} else {
if (IndexLevel != PageLevel) {
STATIC
UINT64*
GetBlockEntryListFromAddress (
IN UINT64 *RootTable,
IN UINT64 RegionStart,
OUT UINTN *TableLevel,
IN OUT UINT64 *BlockEntrySize,
IN OUT UINT64 **LastBlockEntry
)
{
UINTN RootTableLevel;
UINTN RootTableEntryCount;
UINT64 *TranslationTable;
UINT64 *BlockEntry;
UINT64 BlockEntryAddress;
UINTN BaseAddressAlignment;
UINTN PageLevel;
UINTN Index;
UINTN IndexLevel;
UINTN T0SZ;
UINT64 Attributes;
UINT64 TableAttributes;
// Initialize variable
BlockEntry = NULL;
// Ensure the parameters are valid
if (!(TableLevel && BlockEntrySize && LastBlockEntry)) {
ASSERT_EFI_ERROR (EFI_INVALID_PARAMETER);
return NULL;
}
// Ensure the Region is aligned on 4KB boundary
if ((RegionStart & (SIZE_4KB - 1)) != 0) {
ASSERT_EFI_ERROR (EFI_INVALID_PARAMETER);
return NULL;
}
// Ensure the required size is aligned on 4KB boundary
if ((*BlockEntrySize & (SIZE_4KB - 1)) != 0) {
ASSERT_EFI_ERROR (EFI_INVALID_PARAMETER);
return NULL;
}
//
// Calculate LastBlockEntry from T0SZ - this is the last block entry of the root Translation table
//
T0SZ = ArmGetTCR () & TCR_T0SZ_MASK;
// Get the Table info from T0SZ
GetRootTranslationTableInfo (T0SZ, &RootTableLevel, &RootTableEntryCount);
// The last block of the root table depends on the number of entry in this table
*LastBlockEntry = TT_LAST_BLOCK_ADDRESS(RootTable, RootTableEntryCount);
// If the start address is 0x0 then we use the size of the region to identify the alignment
if (RegionStart == 0) {
// Identify the highest possible alignment for the Region Size
for (BaseAddressAlignment = 0; BaseAddressAlignment < 64; BaseAddressAlignment++) {
if ((1 << BaseAddressAlignment) & *BlockEntrySize) {
break;
}
}
} else {
// Identify the highest possible alignment for the Base Address
for (BaseAddressAlignment = 0; BaseAddressAlignment < 64; BaseAddressAlignment++) {
if ((1 << BaseAddressAlignment) & RegionStart) {
break;
}
}
}
// Identify the Page Level the RegionStart must belongs to
PageLevel = 3 - ((BaseAddressAlignment - 12) / 9);
// If the required size is smaller than the current block size then we need to go to the page below.
// The PageLevel was calculated on the Base Address alignment but did not take in account the alignment
// of the allocation size
if (*BlockEntrySize < TT_BLOCK_ENTRY_SIZE_AT_LEVEL (PageLevel)) {
// It does not fit so we need to go a page level above
PageLevel++;
}
// Expose the found PageLevel to the caller
*TableLevel = PageLevel;
// Now, we have the Table Level we can get the Block Size associated to this table
*BlockEntrySize = TT_BLOCK_ENTRY_SIZE_AT_LEVEL (PageLevel);
//
// Get the Table Descriptor for the corresponding PageLevel. We need to decompose RegionStart to get appropriate entries
//
TranslationTable = RootTable;
for (IndexLevel = RootTableLevel; IndexLevel <= PageLevel; IndexLevel++) {
BlockEntry = (UINT64*)TT_GET_ENTRY_FOR_ADDRESS (TranslationTable, IndexLevel, RegionStart);
if ((IndexLevel != 3) && ((*BlockEntry & TT_TYPE_MASK) == TT_TYPE_TABLE_ENTRY)) {
// Go to the next table
TranslationTable = (UINT64*)(*BlockEntry & TT_ADDRESS_MASK_DESCRIPTION_TABLE);
// If we are at the last level then update the output
if (IndexLevel == PageLevel) {
// And get the appropriate BlockEntry at the next level
BlockEntry = (UINT64*)TT_GET_ENTRY_FOR_ADDRESS (TranslationTable, IndexLevel + 1, RegionStart);
// Set the last block for this new table
*LastBlockEntry = TT_LAST_BLOCK_ADDRESS(TranslationTable, TT_ENTRY_COUNT);
}
} else if ((*BlockEntry & TT_TYPE_MASK) == TT_TYPE_BLOCK_ENTRY) {
// If we are not at the last level then we need to split this BlockEntry
if (IndexLevel != PageLevel) {
// Retrieve the attributes from the block entry
Attributes = *BlockEntry & TT_ATTRIBUTES_MASK;
// Convert the block entry attributes into Table descriptor attributes
TableAttributes = TT_TABLE_AP_NO_PERMISSION;
if (Attributes & TT_PXN_MASK) {
TableAttributes = TT_TABLE_PXN;
}
if (Attributes & TT_UXN_MASK) {
TableAttributes = TT_TABLE_XN;
}
if (Attributes & TT_NS) {
TableAttributes = TT_TABLE_NS;
}
// Get the address corresponding at this entry
BlockEntryAddress = RegionStart;
BlockEntryAddress = BlockEntryAddress >> TT_ADDRESS_OFFSET_AT_LEVEL(IndexLevel);
// Shift back to right to set zero before the effective address
BlockEntryAddress = BlockEntryAddress << TT_ADDRESS_OFFSET_AT_LEVEL(IndexLevel);
// Set the correct entry type for the next page level
if ((IndexLevel + 1) == 3) {
Attributes |= TT_TYPE_BLOCK_ENTRY_LEVEL3;
} else {
Attributes |= TT_TYPE_BLOCK_ENTRY;
}
// Create a new translation table
TranslationTable = (UINT64*)AllocatePages (EFI_SIZE_TO_PAGES((TT_ENTRY_COUNT * sizeof(UINT64)) + TT_ALIGNMENT_DESCRIPTION_TABLE));
if (TranslationTable == NULL) {
return NULL;
}
TranslationTable = (UINT64*)((UINTN)TranslationTable & TT_ADDRESS_MASK_DESCRIPTION_TABLE);
// Fill the BlockEntry with the new TranslationTable
*BlockEntry = ((UINTN)TranslationTable & TT_ADDRESS_MASK_DESCRIPTION_TABLE) | TableAttributes | TT_TYPE_TABLE_ENTRY;
// Update the last block entry with the newly created translation table
*LastBlockEntry = TT_LAST_BLOCK_ADDRESS(TranslationTable, TT_ENTRY_COUNT);
// Populate the newly created lower level table
BlockEntry = TranslationTable;
for (Index = 0; Index < TT_ENTRY_COUNT; Index++) {
*BlockEntry = Attributes | (BlockEntryAddress + (Index << TT_ADDRESS_OFFSET_AT_LEVEL(IndexLevel + 1)));
BlockEntry++;
}
// Block Entry points at the beginning of the Translation Table
BlockEntry = TranslationTable;
}
} else {
if (IndexLevel != PageLevel) {
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;
}
