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66509f90fc6636f22e4ea9d6d11655b2f9268b91
system76-edk2/ArmPkg/Library/ArmMmuLib/Arm/ArmMmuLibCore.c
Ard Biesheuvel 66509f90fc ArmPkg/ArmMmuLib ARM: trim high memory regions instead of rejecting them 
ArmSetMemoryAttributes() still chokes in some cases, i.e., when the
length of the region exceeds 4 GB, the subtraction overflows, which
results in the region being misidentified as being 32-bit addressable.

Let's update the logic to trim the length to what we can address with
32 bits. This fixes the issue, and also deals with the issue where an
entire region is disregarded if part of it exceeds beyond what we can
map with 32 bits.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
2019-01-28 20:01:45 +01:00

848 lines
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/** @file
* File managing the MMU for ARMv7 architecture
*
* Copyright (c) 2011-2016, ARM Limited. All rights reserved.
*
* 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 <Uefi.h>
#include <Chipset/ArmV7.h>
#include <Library/BaseMemoryLib.h>
#include <Library/CacheMaintenanceLib.h>
#include <Library/MemoryAllocationLib.h>
#include <Library/ArmLib.h>
#include <Library/BaseLib.h>
#include <Library/DebugLib.h>
#include <Library/PcdLib.h>
#define ID_MMFR0_SHARELVL_SHIFT 12
#define ID_MMFR0_SHARELVL_MASK 0xf
#define ID_MMFR0_SHARELVL_ONE 0
#define ID_MMFR0_SHARELVL_TWO 1
#define ID_MMFR0_INNERSHR_SHIFT 28
#define ID_MMFR0_INNERSHR_MASK 0xf
#define ID_MMFR0_OUTERSHR_SHIFT 8
#define ID_MMFR0_OUTERSHR_MASK 0xf
#define ID_MMFR0_SHR_IMP_UNCACHED 0
#define ID_MMFR0_SHR_IMP_HW_COHERENT 1
#define ID_MMFR0_SHR_IGNORED 0xf
#define __EFI_MEMORY_RWX 0 // no restrictions
#define CACHE_ATTRIBUTE_MASK (EFI_MEMORY_UC | \
EFI_MEMORY_WC | \
EFI_MEMORY_WT | \
EFI_MEMORY_WB | \
EFI_MEMORY_UCE | \
EFI_MEMORY_WP)
UINTN
EFIAPI
ArmReadIdMmfr0 (
VOID
);
BOOLEAN
EFIAPI
ArmHasMpExtensions (
VOID
);
UINT32
ConvertSectionAttributesToPageAttributes (
IN UINT32 SectionAttributes,
IN BOOLEAN IsLargePage
)
{
UINT32 PageAttributes;
PageAttributes = 0;
PageAttributes |= TT_DESCRIPTOR_CONVERT_TO_PAGE_CACHE_POLICY (SectionAttributes, IsLargePage);
PageAttributes |= TT_DESCRIPTOR_CONVERT_TO_PAGE_AP (SectionAttributes);
PageAttributes |= TT_DESCRIPTOR_CONVERT_TO_PAGE_XN (SectionAttributes, IsLargePage);
PageAttributes |= TT_DESCRIPTOR_CONVERT_TO_PAGE_NG (SectionAttributes);
PageAttributes |= TT_DESCRIPTOR_CONVERT_TO_PAGE_S (SectionAttributes);
return PageAttributes;
}
STATIC
BOOLEAN
PreferNonshareableMemory (
VOID
)
{
UINTN Mmfr;
UINTN Val;
if (FeaturePcdGet (PcdNormalMemoryNonshareableOverride)) {
return TRUE;
}
//
// Check whether the innermost level of shareability (the level we will use
// by default to map normal memory) is implemented with hardware coherency
// support. Otherwise, revert to mapping as non-shareable.
//
Mmfr = ArmReadIdMmfr0 ();
switch ((Mmfr >> ID_MMFR0_SHARELVL_SHIFT) & ID_MMFR0_SHARELVL_MASK) {
case ID_MMFR0_SHARELVL_ONE:
// one level of shareability
Val = (Mmfr >> ID_MMFR0_OUTERSHR_SHIFT) & ID_MMFR0_OUTERSHR_MASK;
break;
case ID_MMFR0_SHARELVL_TWO:
// two levels of shareability
Val = (Mmfr >> ID_MMFR0_INNERSHR_SHIFT) & ID_MMFR0_INNERSHR_MASK;
break;
default:
// unexpected value -> shareable is the safe option
ASSERT (FALSE);
return FALSE;
}
return Val != ID_MMFR0_SHR_IMP_HW_COHERENT;
}
STATIC
VOID
PopulateLevel2PageTable (
IN UINT32 *SectionEntry,
IN UINT32 PhysicalBase,
IN UINT32 RemainLength,
IN ARM_MEMORY_REGION_ATTRIBUTES Attributes
)
{
UINT32* PageEntry;
UINT32 Pages;
UINT32 Index;
UINT32 PageAttributes;
UINT32 SectionDescriptor;
UINT32 TranslationTable;
UINT32 BaseSectionAddress;
UINT32 FirstPageOffset;
switch (Attributes) {
case ARM_MEMORY_REGION_ATTRIBUTE_WRITE_BACK:
case ARM_MEMORY_REGION_ATTRIBUTE_NONSECURE_WRITE_BACK:
PageAttributes = TT_DESCRIPTOR_PAGE_WRITE_BACK;
break;
case ARM_MEMORY_REGION_ATTRIBUTE_WRITE_BACK_NONSHAREABLE:
case ARM_MEMORY_REGION_ATTRIBUTE_NONSECURE_WRITE_BACK_NONSHAREABLE:
PageAttributes = TT_DESCRIPTOR_PAGE_WRITE_BACK;
PageAttributes &= ~TT_DESCRIPTOR_PAGE_S_SHARED;
break;
case ARM_MEMORY_REGION_ATTRIBUTE_WRITE_THROUGH:
case ARM_MEMORY_REGION_ATTRIBUTE_NONSECURE_WRITE_THROUGH:
PageAttributes = TT_DESCRIPTOR_PAGE_WRITE_THROUGH;
break;
case ARM_MEMORY_REGION_ATTRIBUTE_DEVICE:
case ARM_MEMORY_REGION_ATTRIBUTE_NONSECURE_DEVICE:
PageAttributes = TT_DESCRIPTOR_PAGE_DEVICE;
break;
case ARM_MEMORY_REGION_ATTRIBUTE_UNCACHED_UNBUFFERED:
case ARM_MEMORY_REGION_ATTRIBUTE_NONSECURE_UNCACHED_UNBUFFERED:
PageAttributes = TT_DESCRIPTOR_PAGE_UNCACHED;
break;
default:
PageAttributes = TT_DESCRIPTOR_PAGE_UNCACHED;
break;
}
if (PreferNonshareableMemory ()) {
PageAttributes &= ~TT_DESCRIPTOR_PAGE_S_SHARED;
}
// Check if the Section Entry has already been populated. Otherwise attach a
// Level 2 Translation Table to it
if (*SectionEntry != 0) {
// The entry must be a page table. Otherwise it exists an overlapping in the memory map
if (TT_DESCRIPTOR_SECTION_TYPE_IS_PAGE_TABLE(*SectionEntry)) {
TranslationTable = *SectionEntry & TT_DESCRIPTOR_SECTION_PAGETABLE_ADDRESS_MASK;
} else if ((*SectionEntry & TT_DESCRIPTOR_SECTION_TYPE_MASK) == TT_DESCRIPTOR_SECTION_TYPE_SECTION) {
// Case where a virtual memory map descriptor overlapped a section entry
// Allocate a Level2 Page Table for this Section
TranslationTable = (UINTN)AllocatePages(EFI_SIZE_TO_PAGES(TRANSLATION_TABLE_PAGE_SIZE + TRANSLATION_TABLE_PAGE_ALIGNMENT));
TranslationTable = ((UINTN)TranslationTable + TRANSLATION_TABLE_PAGE_ALIGNMENT_MASK) & ~TRANSLATION_TABLE_PAGE_ALIGNMENT_MASK;
// Translate the Section Descriptor into Page Descriptor
SectionDescriptor = TT_DESCRIPTOR_PAGE_TYPE_PAGE | ConvertSectionAttributesToPageAttributes (*SectionEntry, FALSE);
BaseSectionAddress = TT_DESCRIPTOR_SECTION_BASE_ADDRESS(*SectionEntry);
// Populate the new Level2 Page Table for the section
PageEntry = (UINT32*)TranslationTable;
for (Index = 0; Index < TRANSLATION_TABLE_PAGE_COUNT; Index++) {
PageEntry[Index] = TT_DESCRIPTOR_PAGE_BASE_ADDRESS(BaseSectionAddress + (Index << 12)) | SectionDescriptor;
}
// Overwrite the section entry to point to the new Level2 Translation Table
*SectionEntry = (TranslationTable & TT_DESCRIPTOR_SECTION_PAGETABLE_ADDRESS_MASK) |
(IS_ARM_MEMORY_REGION_ATTRIBUTES_SECURE(Attributes) ? (1 << 3) : 0) |
TT_DESCRIPTOR_SECTION_TYPE_PAGE_TABLE;
} else {
// We do not support the other section type (16MB Section)
ASSERT(0);
return;
}
} else {
TranslationTable = (UINTN)AllocatePages(EFI_SIZE_TO_PAGES(TRANSLATION_TABLE_PAGE_SIZE + TRANSLATION_TABLE_PAGE_ALIGNMENT));
TranslationTable = ((UINTN)TranslationTable + TRANSLATION_TABLE_PAGE_ALIGNMENT_MASK) & ~TRANSLATION_TABLE_PAGE_ALIGNMENT_MASK;
ZeroMem ((VOID *)TranslationTable, TRANSLATION_TABLE_PAGE_SIZE);
*SectionEntry = (TranslationTable & TT_DESCRIPTOR_SECTION_PAGETABLE_ADDRESS_MASK) |
(IS_ARM_MEMORY_REGION_ATTRIBUTES_SECURE(Attributes) ? (1 << 3) : 0) |
TT_DESCRIPTOR_SECTION_TYPE_PAGE_TABLE;
}
FirstPageOffset = (PhysicalBase & TT_DESCRIPTOR_PAGE_INDEX_MASK) >> TT_DESCRIPTOR_PAGE_BASE_SHIFT;
PageEntry = (UINT32 *)TranslationTable + FirstPageOffset;
Pages = RemainLength / TT_DESCRIPTOR_PAGE_SIZE;
ASSERT (FirstPageOffset + Pages <= TRANSLATION_TABLE_PAGE_COUNT);
for (Index = 0; Index < Pages; Index++) {
*PageEntry++ = TT_DESCRIPTOR_PAGE_BASE_ADDRESS(PhysicalBase) | PageAttributes;
PhysicalBase += TT_DESCRIPTOR_PAGE_SIZE;
}
}
STATIC
VOID
FillTranslationTable (
IN UINT32 *TranslationTable,
IN ARM_MEMORY_REGION_DESCRIPTOR *MemoryRegion
)
{
UINT32 *SectionEntry;
UINT32 Attributes;
UINT32 PhysicalBase;
UINT64 RemainLength;
UINT32 PageMapLength;
ASSERT(MemoryRegion->Length > 0);
if (MemoryRegion->PhysicalBase >= SIZE_4GB) {
return;
}
PhysicalBase = MemoryRegion->PhysicalBase;
RemainLength = MIN(MemoryRegion->Length, SIZE_4GB - PhysicalBase);
switch (MemoryRegion->Attributes) {
case ARM_MEMORY_REGION_ATTRIBUTE_WRITE_BACK:
Attributes = TT_DESCRIPTOR_SECTION_WRITE_BACK(0);
break;
case ARM_MEMORY_REGION_ATTRIBUTE_WRITE_BACK_NONSHAREABLE:
Attributes = TT_DESCRIPTOR_SECTION_WRITE_BACK(0);
Attributes &= ~TT_DESCRIPTOR_SECTION_S_SHARED;
break;
case ARM_MEMORY_REGION_ATTRIBUTE_WRITE_THROUGH:
Attributes = TT_DESCRIPTOR_SECTION_WRITE_THROUGH(0);
break;
case ARM_MEMORY_REGION_ATTRIBUTE_DEVICE:
Attributes = TT_DESCRIPTOR_SECTION_DEVICE(0);
break;
case ARM_MEMORY_REGION_ATTRIBUTE_UNCACHED_UNBUFFERED:
Attributes = TT_DESCRIPTOR_SECTION_UNCACHED(0);
break;
case ARM_MEMORY_REGION_ATTRIBUTE_NONSECURE_WRITE_BACK:
Attributes = TT_DESCRIPTOR_SECTION_WRITE_BACK(1);
break;
case ARM_MEMORY_REGION_ATTRIBUTE_NONSECURE_WRITE_BACK_NONSHAREABLE:
Attributes = TT_DESCRIPTOR_SECTION_WRITE_BACK(1);
Attributes &= ~TT_DESCRIPTOR_SECTION_S_SHARED;
break;
case ARM_MEMORY_REGION_ATTRIBUTE_NONSECURE_WRITE_THROUGH:
Attributes = TT_DESCRIPTOR_SECTION_WRITE_THROUGH(1);
break;
case ARM_MEMORY_REGION_ATTRIBUTE_NONSECURE_DEVICE:
Attributes = TT_DESCRIPTOR_SECTION_DEVICE(1);
break;
case ARM_MEMORY_REGION_ATTRIBUTE_NONSECURE_UNCACHED_UNBUFFERED:
Attributes = TT_DESCRIPTOR_SECTION_UNCACHED(1);
break;
default:
Attributes = TT_DESCRIPTOR_SECTION_UNCACHED(0);
break;
}
if (PreferNonshareableMemory ()) {
Attributes &= ~TT_DESCRIPTOR_SECTION_S_SHARED;
}
// Get the first section entry for this mapping
SectionEntry = TRANSLATION_TABLE_ENTRY_FOR_VIRTUAL_ADDRESS(TranslationTable, MemoryRegion->VirtualBase);
while (RemainLength != 0) {
if (PhysicalBase % TT_DESCRIPTOR_SECTION_SIZE == 0 &&
RemainLength >= TT_DESCRIPTOR_SECTION_SIZE) {
// Case: Physical address aligned on the Section Size (1MB) && the length
// is greater than the Section Size
*SectionEntry++ = TT_DESCRIPTOR_SECTION_BASE_ADDRESS(PhysicalBase) | Attributes;
PhysicalBase += TT_DESCRIPTOR_SECTION_SIZE;
RemainLength -= TT_DESCRIPTOR_SECTION_SIZE;
} else {
PageMapLength = MIN (RemainLength, TT_DESCRIPTOR_SECTION_SIZE -
(PhysicalBase % TT_DESCRIPTOR_SECTION_SIZE));
// Case: Physical address aligned on the Section Size (1MB) && the length
// does not fill a section
// Case: Physical address NOT aligned on the Section Size (1MB)
PopulateLevel2PageTable (SectionEntry++, PhysicalBase, PageMapLength,
MemoryRegion->Attributes);
// If it is the last entry
if (RemainLength < TT_DESCRIPTOR_SECTION_SIZE) {
break;
}
PhysicalBase += PageMapLength;
RemainLength -= PageMapLength;
}
}
}
RETURN_STATUS
EFIAPI
ArmConfigureMmu (
IN ARM_MEMORY_REGION_DESCRIPTOR *MemoryTable,
OUT VOID **TranslationTableBase OPTIONAL,
OUT UINTN *TranslationTableSize OPTIONAL
)
{
VOID* TranslationTable;
ARM_MEMORY_REGION_ATTRIBUTES TranslationTableAttribute;
UINT32 TTBRAttributes;
// Allocate pages for translation table.
TranslationTable = AllocatePages (EFI_SIZE_TO_PAGES (TRANSLATION_TABLE_SECTION_SIZE + TRANSLATION_TABLE_SECTION_ALIGNMENT));
if (TranslationTable == NULL) {
return RETURN_OUT_OF_RESOURCES;
}
TranslationTable = (VOID*)(((UINTN)TranslationTable + TRANSLATION_TABLE_SECTION_ALIGNMENT_MASK) & ~TRANSLATION_TABLE_SECTION_ALIGNMENT_MASK);
if (TranslationTableBase != NULL) {
*TranslationTableBase = TranslationTable;
}
if (TranslationTableSize != NULL) {
*TranslationTableSize = TRANSLATION_TABLE_SECTION_SIZE;
}
ZeroMem (TranslationTable, TRANSLATION_TABLE_SECTION_SIZE);
// By default, mark the translation table as belonging to a uncached region
TranslationTableAttribute = ARM_MEMORY_REGION_ATTRIBUTE_UNCACHED_UNBUFFERED;
while (MemoryTable->Length != 0) {
// Find the memory attribute for the Translation Table
if (((UINTN)TranslationTable >= MemoryTable->PhysicalBase) && ((UINTN)TranslationTable <= MemoryTable->PhysicalBase - 1 + MemoryTable->Length)) {
TranslationTableAttribute = MemoryTable->Attributes;
}
FillTranslationTable (TranslationTable, MemoryTable);
MemoryTable++;
}
// Translate the Memory Attributes into Translation Table Register Attributes
if ((TranslationTableAttribute == ARM_MEMORY_REGION_ATTRIBUTE_WRITE_BACK) ||
(TranslationTableAttribute == ARM_MEMORY_REGION_ATTRIBUTE_NONSECURE_WRITE_BACK)) {
TTBRAttributes = ArmHasMpExtensions () ? TTBR_MP_WRITE_BACK_ALLOC : TTBR_WRITE_BACK_ALLOC;
} else {
// Page tables must reside in memory mapped as write-back cacheable
ASSERT (0);
return RETURN_UNSUPPORTED;
}
if (TTBRAttributes & TTBR_SHAREABLE) {
if (PreferNonshareableMemory ()) {
TTBRAttributes ^= TTBR_SHAREABLE;
} else {
//
// Unlike the S bit in the short descriptors, which implies inner shareable
// on an implementation that supports two levels, the meaning of the S bit
// in the TTBR depends on the NOS bit, which defaults to Outer Shareable.
// However, we should only set this bit after we have confirmed that the
// implementation supports multiple levels, or else the NOS bit is UNK/SBZP
//
if (((ArmReadIdMmfr0 () >> 12) & 0xf) != 0) {
TTBRAttributes |= TTBR_NOT_OUTER_SHAREABLE;
}
}
}
ArmCleanInvalidateDataCache ();
ArmInvalidateInstructionCache ();
ArmDisableDataCache ();
ArmDisableInstructionCache();
// TLBs are also invalidated when calling ArmDisableMmu()
ArmDisableMmu ();
// Make sure nothing sneaked into the cache
ArmCleanInvalidateDataCache ();
ArmInvalidateInstructionCache ();
ArmSetTTBR0 ((VOID *)(UINTN)(((UINTN)TranslationTable & ~TRANSLATION_TABLE_SECTION_ALIGNMENT_MASK) | (TTBRAttributes & 0x7F)));
//
// The TTBCR register value is undefined at reset in the Non-Secure world.
// Writing 0 has the effect of:
// Clearing EAE: Use short descriptors, as mandated by specification.
// Clearing PD0 and PD1: Translation Table Walk Disable is off.
// Clearing N: Perform all translation table walks through TTBR0.
// (0 is the default reset value in systems not implementing
// the Security Extensions.)
//
ArmSetTTBCR (0);
ArmSetDomainAccessControl (DOMAIN_ACCESS_CONTROL_NONE(15) |
DOMAIN_ACCESS_CONTROL_NONE(14) |
DOMAIN_ACCESS_CONTROL_NONE(13) |
DOMAIN_ACCESS_CONTROL_NONE(12) |
DOMAIN_ACCESS_CONTROL_NONE(11) |
DOMAIN_ACCESS_CONTROL_NONE(10) |
DOMAIN_ACCESS_CONTROL_NONE( 9) |
DOMAIN_ACCESS_CONTROL_NONE( 8) |
DOMAIN_ACCESS_CONTROL_NONE( 7) |
DOMAIN_ACCESS_CONTROL_NONE( 6) |
DOMAIN_ACCESS_CONTROL_NONE( 5) |
DOMAIN_ACCESS_CONTROL_NONE( 4) |
DOMAIN_ACCESS_CONTROL_NONE( 3) |
DOMAIN_ACCESS_CONTROL_NONE( 2) |
DOMAIN_ACCESS_CONTROL_NONE( 1) |
DOMAIN_ACCESS_CONTROL_CLIENT(0));
ArmEnableInstructionCache();
ArmEnableDataCache();
ArmEnableMmu();
return RETURN_SUCCESS;
}
STATIC
EFI_STATUS
ConvertSectionToPages (
IN EFI_PHYSICAL_ADDRESS BaseAddress
)
{
UINT32 FirstLevelIdx;
UINT32 SectionDescriptor;
UINT32 PageTableDescriptor;
UINT32 PageDescriptor;
UINT32 Index;
volatile ARM_FIRST_LEVEL_DESCRIPTOR *FirstLevelTable;
volatile ARM_PAGE_TABLE_ENTRY *PageTable;
DEBUG ((EFI_D_PAGE, "Converting section at 0x%x to pages\n", (UINTN)BaseAddress));
// Obtain page table base
FirstLevelTable = (ARM_FIRST_LEVEL_DESCRIPTOR *)ArmGetTTBR0BaseAddress ();
// Calculate index into first level translation table for start of modification
FirstLevelIdx = TT_DESCRIPTOR_SECTION_BASE_ADDRESS(BaseAddress) >> TT_DESCRIPTOR_SECTION_BASE_SHIFT;
ASSERT (FirstLevelIdx < TRANSLATION_TABLE_SECTION_COUNT);
// Get section attributes and convert to page attributes
SectionDescriptor = FirstLevelTable[FirstLevelIdx];
PageDescriptor = TT_DESCRIPTOR_PAGE_TYPE_PAGE | ConvertSectionAttributesToPageAttributes (SectionDescriptor, FALSE);
// Allocate a page table for the 4KB entries (we use up a full page even though we only need 1KB)
PageTable = (volatile ARM_PAGE_TABLE_ENTRY *)AllocatePages (1);
if (PageTable == NULL) {
return EFI_OUT_OF_RESOURCES;
}
// Write the page table entries out
for (Index = 0; Index < TRANSLATION_TABLE_PAGE_COUNT; Index++) {
PageTable[Index] = TT_DESCRIPTOR_PAGE_BASE_ADDRESS(BaseAddress + (Index << 12)) | PageDescriptor;
}
// Formulate page table entry, Domain=0, NS=0
PageTableDescriptor = (((UINTN)PageTable) & TT_DESCRIPTOR_SECTION_PAGETABLE_ADDRESS_MASK) | TT_DESCRIPTOR_SECTION_TYPE_PAGE_TABLE;
// Write the page table entry out, replacing section entry
FirstLevelTable[FirstLevelIdx] = PageTableDescriptor;
return EFI_SUCCESS;
}
STATIC
EFI_STATUS
UpdatePageEntries (
IN EFI_PHYSICAL_ADDRESS BaseAddress,
IN UINT64 Length,
IN UINT64 Attributes,
OUT BOOLEAN *FlushTlbs OPTIONAL
)
{
EFI_STATUS Status;
UINT32 EntryValue;
UINT32 EntryMask;
UINT32 FirstLevelIdx;
UINT32 Offset;
UINT32 NumPageEntries;
UINT32 Descriptor;
UINT32 p;
UINT32 PageTableIndex;
UINT32 PageTableEntry;
UINT32 CurrentPageTableEntry;
VOID *Mva;
volatile ARM_FIRST_LEVEL_DESCRIPTOR *FirstLevelTable;
volatile ARM_PAGE_TABLE_ENTRY *PageTable;
Status = EFI_SUCCESS;
// EntryMask: bitmask of values to change (1 = change this value, 0 = leave alone)
// EntryValue: values at bit positions specified by EntryMask
EntryMask = TT_DESCRIPTOR_PAGE_TYPE_MASK | TT_DESCRIPTOR_PAGE_AP_MASK;
if (Attributes & EFI_MEMORY_XP) {
EntryValue = TT_DESCRIPTOR_PAGE_TYPE_PAGE_XN;
} else {
EntryValue = TT_DESCRIPTOR_PAGE_TYPE_PAGE;
}
// Although the PI spec is unclear on this, the GCD guarantees that only
// one Attribute bit is set at a time, so the order of the conditionals below
// is irrelevant. If no memory attribute is specified, we preserve whatever
// memory type is set in the page tables, and update the permission attributes
// only.
if (Attributes & EFI_MEMORY_UC) {
// modify cacheability attributes
EntryMask |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_MASK;
// map to strongly ordered
EntryValue |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_STRONGLY_ORDERED; // TEX[2:0] = 0, C=0, B=0
} else if (Attributes & EFI_MEMORY_WC) {
// modify cacheability attributes
EntryMask |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_MASK;
// map to normal non-cachable
EntryValue |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_NON_CACHEABLE; // TEX [2:0]= 001 = 0x2, B=0, C=0
} else if (Attributes & EFI_MEMORY_WT) {
// modify cacheability attributes
EntryMask |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_MASK;
// write through with no-allocate
EntryValue |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_WRITE_THROUGH_NO_ALLOC; // TEX [2:0] = 0, C=1, B=0
} else if (Attributes & EFI_MEMORY_WB) {
// modify cacheability attributes
EntryMask |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_MASK;
// write back (with allocate)
EntryValue |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_WRITE_BACK_ALLOC; // TEX [2:0] = 001, C=1, B=1
} else if (Attributes & CACHE_ATTRIBUTE_MASK) {
// catch unsupported memory type attributes
ASSERT (FALSE);
return EFI_UNSUPPORTED;
}
if (Attributes & EFI_MEMORY_RO) {
EntryValue |= TT_DESCRIPTOR_PAGE_AP_RO_RO;
} else {
EntryValue |= TT_DESCRIPTOR_PAGE_AP_RW_RW;
}
// Obtain page table base
FirstLevelTable = (ARM_FIRST_LEVEL_DESCRIPTOR *)ArmGetTTBR0BaseAddress ();
// Calculate number of 4KB page table entries to change
NumPageEntries = Length / TT_DESCRIPTOR_PAGE_SIZE;
// Iterate for the number of 4KB pages to change
Offset = 0;
for(p = 0; p < NumPageEntries; p++) {
// Calculate index into first level translation table for page table value
FirstLevelIdx = TT_DESCRIPTOR_SECTION_BASE_ADDRESS(BaseAddress + Offset) >> TT_DESCRIPTOR_SECTION_BASE_SHIFT;
ASSERT (FirstLevelIdx < TRANSLATION_TABLE_SECTION_COUNT);
// Read the descriptor from the first level page table
Descriptor = FirstLevelTable[FirstLevelIdx];
// Does this descriptor need to be converted from section entry to 4K pages?
if (!TT_DESCRIPTOR_SECTION_TYPE_IS_PAGE_TABLE(Descriptor)) {
Status = ConvertSectionToPages (FirstLevelIdx << TT_DESCRIPTOR_SECTION_BASE_SHIFT);
if (EFI_ERROR(Status)) {
// Exit for loop
break;
}
// Re-read descriptor
Descriptor = FirstLevelTable[FirstLevelIdx];
if (FlushTlbs != NULL) {
*FlushTlbs = TRUE;
}
}
// Obtain page table base address
PageTable = (ARM_PAGE_TABLE_ENTRY *)TT_DESCRIPTOR_PAGE_BASE_ADDRESS(Descriptor);
// Calculate index into the page table
PageTableIndex = ((BaseAddress + Offset) & TT_DESCRIPTOR_PAGE_INDEX_MASK) >> TT_DESCRIPTOR_PAGE_BASE_SHIFT;
ASSERT (PageTableIndex < TRANSLATION_TABLE_PAGE_COUNT);
// Get the entry
CurrentPageTableEntry = PageTable[PageTableIndex];
// Mask off appropriate fields
PageTableEntry = CurrentPageTableEntry & ~EntryMask;
// Mask in new attributes and/or permissions
PageTableEntry |= EntryValue;
if (CurrentPageTableEntry != PageTableEntry) {
Mva = (VOID *)(UINTN)((((UINTN)FirstLevelIdx) << TT_DESCRIPTOR_SECTION_BASE_SHIFT) + (PageTableIndex << TT_DESCRIPTOR_PAGE_BASE_SHIFT));
// Only need to update if we are changing the entry
PageTable[PageTableIndex] = PageTableEntry;
ArmUpdateTranslationTableEntry ((VOID *)&PageTable[PageTableIndex], Mva);
}
Status = EFI_SUCCESS;
Offset += TT_DESCRIPTOR_PAGE_SIZE;
} // End first level translation table loop
return Status;
}
STATIC
EFI_STATUS
UpdateSectionEntries (
IN EFI_PHYSICAL_ADDRESS BaseAddress,
IN UINT64 Length,
IN UINT64 Attributes
)
{
EFI_STATUS Status = EFI_SUCCESS;
UINT32 EntryMask;
UINT32 EntryValue;
UINT32 FirstLevelIdx;
UINT32 NumSections;
UINT32 i;
UINT32 CurrentDescriptor;
UINT32 Descriptor;
VOID *Mva;
volatile ARM_FIRST_LEVEL_DESCRIPTOR *FirstLevelTable;
// EntryMask: bitmask of values to change (1 = change this value, 0 = leave alone)
// EntryValue: values at bit positions specified by EntryMask
// Make sure we handle a section range that is unmapped
EntryMask = TT_DESCRIPTOR_SECTION_TYPE_MASK | TT_DESCRIPTOR_SECTION_XN_MASK |
TT_DESCRIPTOR_SECTION_AP_MASK;
EntryValue = TT_DESCRIPTOR_SECTION_TYPE_SECTION;
// Although the PI spec is unclear on this, the GCD guarantees that only
// one Attribute bit is set at a time, so the order of the conditionals below
// is irrelevant. If no memory attribute is specified, we preserve whatever
// memory type is set in the page tables, and update the permission attributes
// only.
if (Attributes & EFI_MEMORY_UC) {
// modify cacheability attributes
EntryMask |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_MASK;
// map to strongly ordered
EntryValue |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_STRONGLY_ORDERED; // TEX[2:0] = 0, C=0, B=0
} else if (Attributes & EFI_MEMORY_WC) {
// modify cacheability attributes
EntryMask |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_MASK;
// map to normal non-cachable
EntryValue |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_NON_CACHEABLE; // TEX [2:0]= 001 = 0x2, B=0, C=0
} else if (Attributes & EFI_MEMORY_WT) {
// modify cacheability attributes
EntryMask |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_MASK;
// write through with no-allocate
EntryValue |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_WRITE_THROUGH_NO_ALLOC; // TEX [2:0] = 0, C=1, B=0
} else if (Attributes & EFI_MEMORY_WB) {
// modify cacheability attributes
EntryMask |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_MASK;
// write back (with allocate)
EntryValue |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_WRITE_BACK_ALLOC; // TEX [2:0] = 001, C=1, B=1
} else if (Attributes & CACHE_ATTRIBUTE_MASK) {
// catch unsupported memory type attributes
ASSERT (FALSE);
return EFI_UNSUPPORTED;
}
if (Attributes & EFI_MEMORY_RO) {
EntryValue |= TT_DESCRIPTOR_SECTION_AP_RO_RO;
} else {
EntryValue |= TT_DESCRIPTOR_SECTION_AP_RW_RW;
}
if (Attributes & EFI_MEMORY_XP) {
EntryValue |= TT_DESCRIPTOR_SECTION_XN_MASK;
}
// obtain page table base
FirstLevelTable = (ARM_FIRST_LEVEL_DESCRIPTOR *)ArmGetTTBR0BaseAddress ();
// calculate index into first level translation table for start of modification
FirstLevelIdx = TT_DESCRIPTOR_SECTION_BASE_ADDRESS(BaseAddress) >> TT_DESCRIPTOR_SECTION_BASE_SHIFT;
ASSERT (FirstLevelIdx < TRANSLATION_TABLE_SECTION_COUNT);
// calculate number of 1MB first level entries this applies to
NumSections = Length / TT_DESCRIPTOR_SECTION_SIZE;
// iterate through each descriptor
for(i=0; i<NumSections; i++) {
CurrentDescriptor = FirstLevelTable[FirstLevelIdx + i];
// has this descriptor already been coverted to pages?
if (TT_DESCRIPTOR_SECTION_TYPE_IS_PAGE_TABLE(CurrentDescriptor)) {
// forward this 1MB range to page table function instead
Status = UpdatePageEntries (
(FirstLevelIdx + i) << TT_DESCRIPTOR_SECTION_BASE_SHIFT,
TT_DESCRIPTOR_SECTION_SIZE,
Attributes,
NULL);
} else {
// still a section entry
if (CurrentDescriptor != 0) {
// mask off appropriate fields
Descriptor = CurrentDescriptor & ~EntryMask;
} else {
Descriptor = ((UINTN)FirstLevelIdx + i) << TT_DESCRIPTOR_SECTION_BASE_SHIFT;
}
// mask in new attributes and/or permissions
Descriptor |= EntryValue;
if (CurrentDescriptor != Descriptor) {
Mva = (VOID *)(UINTN)(((UINTN)FirstLevelIdx + i) << TT_DESCRIPTOR_SECTION_BASE_SHIFT);
// Only need to update if we are changing the descriptor
FirstLevelTable[FirstLevelIdx + i] = Descriptor;
ArmUpdateTranslationTableEntry ((VOID *)&FirstLevelTable[FirstLevelIdx + i], Mva);
}
Status = EFI_SUCCESS;
}
}
return Status;
}
EFI_STATUS
ArmSetMemoryAttributes (
IN EFI_PHYSICAL_ADDRESS BaseAddress,
IN UINT64 Length,
IN UINT64 Attributes
)
{
EFI_STATUS Status;
UINT64 ChunkLength;
BOOLEAN FlushTlbs;
if (BaseAddress > (UINT64)MAX_ADDRESS) {
return EFI_UNSUPPORTED;
}
Length = MIN (Length, (UINT64)MAX_ADDRESS - BaseAddress + 1);
if (Length == 0) {
return EFI_SUCCESS;
}
FlushTlbs = FALSE;
while (Length > 0) {
if ((BaseAddress % TT_DESCRIPTOR_SECTION_SIZE == 0) &&
Length >= TT_DESCRIPTOR_SECTION_SIZE) {
ChunkLength = Length - Length % TT_DESCRIPTOR_SECTION_SIZE;
DEBUG ((DEBUG_PAGE,
"SetMemoryAttributes(): MMU section 0x%lx length 0x%lx to %lx\n",
BaseAddress, ChunkLength, Attributes));
Status = UpdateSectionEntries (BaseAddress, ChunkLength, Attributes);
FlushTlbs = TRUE;
} else {
//
// Process page by page until the next section boundary, but only if
// we have more than a section's worth of area to deal with after that.
//
ChunkLength = TT_DESCRIPTOR_SECTION_SIZE -
(BaseAddress % TT_DESCRIPTOR_SECTION_SIZE);
if (ChunkLength + TT_DESCRIPTOR_SECTION_SIZE > Length) {
ChunkLength = Length;
}
DEBUG ((DEBUG_PAGE,
"SetMemoryAttributes(): MMU page 0x%lx length 0x%lx to %lx\n",
BaseAddress, ChunkLength, Attributes));
Status = UpdatePageEntries (BaseAddress, ChunkLength, Attributes,
&FlushTlbs);
}
if (EFI_ERROR (Status)) {
break;
}
BaseAddress += ChunkLength;
Length -= ChunkLength;
}
if (FlushTlbs) {
ArmInvalidateTlb ();
}
return Status;
}
EFI_STATUS
ArmSetMemoryRegionNoExec (
IN EFI_PHYSICAL_ADDRESS BaseAddress,
IN UINT64 Length
)
{
return ArmSetMemoryAttributes (BaseAddress, Length, EFI_MEMORY_XP);
}
EFI_STATUS
ArmClearMemoryRegionNoExec (
IN EFI_PHYSICAL_ADDRESS BaseAddress,
IN UINT64 Length
)
{
return ArmSetMemoryAttributes (BaseAddress, Length, __EFI_MEMORY_RWX);
}
EFI_STATUS
ArmSetMemoryRegionReadOnly (
IN EFI_PHYSICAL_ADDRESS BaseAddress,
IN UINT64 Length
)
{
return ArmSetMemoryAttributes (BaseAddress, Length, EFI_MEMORY_RO);
}
EFI_STATUS
ArmClearMemoryRegionReadOnly (
IN EFI_PHYSICAL_ADDRESS BaseAddress,
IN UINT64 Length
)
{
return ArmSetMemoryAttributes (BaseAddress, Length, __EFI_MEMORY_RWX);
}
RETURN_STATUS
EFIAPI
ArmMmuBaseLibConstructor (
VOID
)
{
return RETURN_SUCCESS;
}
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