audk/ArmPkg/Drivers/CpuDxe/Mmu.c

917 lines
33 KiB
C

/*++
Copyright (c) 2009, Hewlett-Packard Company. All rights reserved.<BR>
Portions copyright (c) 2010, Apple Inc. 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 "CpuDxe.h"
//
// Translation/page table definitions
//
// First Level Descriptors
typedef UINT32 ARM_FIRST_LEVEL_DESCRIPTOR;
// memory space covered by a first level descriptor
#define ARM_PAGE_DESC_ENTRY_MVA_SIZE 0x00100000 // 1MB
// number of first level descriptors to cover entire 32-bit memory space
#define FIRST_LEVEL_ENTRY_COUNT (0xFFFFFFFF / ARM_PAGE_DESC_ENTRY_MVA_SIZE + 1)
// page table 1st level descriptor entries
#define ARM_PAGE_DESC_BASE_MASK 0xFFFFFC00
#define ARM_PAGE_DESC_BASE_SHFIT 10
#define ARM_PAGE_DESC_DOMAIN_MASK 0x000001E0
#define ARM_PAGE_DESC_DOMAIN_SHIFT 5
#define ARM_PAGE_DESC_NS 0x00000008
#define ARM_FIRST_LEVEL_DESC_ALIGN 0x00004000 // 16KB
// section 1st level desriptor entries
#define ARM_SECTION_BASE_MASK 0xFFF00000
#define ARM_SECTION_BASE_SHIFT 20
#define ARM_SECTION_NS 0x00080000
#define ARM_SECTION_nG 0x00020000
#define ARM_SECTION_S 0x00010000
#define ARM_SECTION_AP2 0x00008000
#define ARM_SECTION_TEX_MASK 0x00007000
#define ARM_SECTION_TEX_SHIFT 12
#define ARM_SECTION_AP10_MASK 0x00000C00
#define ARM_SECTION_AP10_SHIFT 10
#define ARM_SECTION_DOMAIN_MASK 0x000001E0
#define ARM_SECTION_DOMAIN_SHIFT 5
#define ARM_SECTION_XN 0x00000010
#define ARM_SECTION_C 0x00000008
#define ARM_SECTION_B 0x00000004
// section level AP[2:0] definitions
#define ARM_SECTION_AP_NO_ACCESS 0 // AP[2:0] = 0
#define ARM_SECTION_AP_READ_WRITE ARM_SECTION_AP10_MASK // AP[2:0] = 011
#define ARM_SECTION_AP_READ_ONLY (ARM_SECTION_AP2 | ARM_SECTION_AP10_MASK) // AP[2:0] = 111
// common 1st level descriptor fields
#define ARM_DESC_TYPE_MASK 0x00000003
// descriptor type values
#define ARM_DESC_TYPE_FAULT 0x0
#define ARM_DESC_TYPE_PAGE_TABLE 0x1
#define ARM_DESC_TYPE_SECTION 0x2
// Second Level Descriptors
typedef UINT32 ARM_PAGE_TABLE_ENTRY;
// small page 2nd level descriptor entries
#define ARM_SMALL_PAGE_BASE_MASK 0xFFFFF000
#define ARM_SMALL_PAGE_INDEX_MASK 0x000FF000
#define ARM_SMALL_PAGE_BASE_SHIFT 12
#define ARM_SMALL_PAGE_TEX_MASK 0x000001C0
#define ARM_SMALL_PAGE_TEX_SHIFT 6
#define ARM_SMALL_PAGE_XN 0x00000001
// large page 2nd level descriptor entries
#define ARM_LARGE_PAGE_BASE_MASK 0xFFFF0000
#define ARM_LARGE_PAGE_BASE_SHIFT 16
#define ARM_LARGE_PAGE_TEX_MASK 0x00007000
#define ARM_LARGE_PAGE_TEX_SHIFT 12
#define ARM_LARGE_PAGE_XN 0x00008000
// common 2nd level desriptor fields
#define ARM_PAGE_nG 0x00000800
#define ARM_PAGE_S 0x00000400
#define ARM_PAGE_AP2 0x00000200
#define ARM_PAGE_AP10_MASK 0x00000030
#define ARM_PAGE_AP10_SHIFT 4
#define ARM_PAGE_C 0x00000008
#define ARM_PAGE_B 0x00000004
#define ARM_PAGE_DESC_TYPE_MASK 0x00000003
// descriptor type values
#define ARM_PAGE_TYPE_FAULT 0x0
#define ARM_PAGE_TYPE_LARGE 0x1
#define ARM_PAGE_TYPE_SMALL 0x2
#define ARM_PAGE_TYPE_SMALL_XN 0x3
#define SMALL_PAGE_TABLE_ENTRY_COUNT (ARM_PAGE_DESC_ENTRY_MVA_SIZE / SIZE_4KB)
// Translation Table Base 0 fields
#define ARM_TTBR0_BASE_MASK 0xFFFFC000
#define ARM_TTBR0_BASE_SHIFT 14
#define ARM_TTRB0_NOS 0x00000020
// define the combination of interesting attributes: cacheability and access permissions
#define ARM_SECTION_CACHEABILITY_MASK ( ARM_SECTION_TEX_MASK | ARM_SECTION_C | ARM_SECTION_B )
#define ARM_SECTION_RW_PERMISSIONS_MASK ( ARM_SECTION_AP2 | ARM_SECTION_AP10_MASK )
#define ARM_DESCRIPTOR_ATTRIBUTES ( ARM_SECTION_CACHEABILITY_MASK | ARM_SECTION_RW_PERMISSIONS_MASK | ARM_SECTION_XN )
// cacheability values for section entries
#define ARM_SECTION_STRONGLY_ORDERED 0
#define ARM_SECTION_SHAREABLE_DEVICE ARM_SECTION_B
#define ARM_SECTION_WRITE_THROUGH ARM_SECTION_C
#define ARM_SECTION_WRITE_BACK_NWA ( ARM_SECTION_C| ARM_SECTION_B )
#define ARM_SECTION_NORMAL_UNCACHEABLE ( 0x1 << ARM_SECTION_TEX_SHIFT )
#define ARM_SECTION_WRITE_BACK ( ( 0x1 << ARM_SECTION_TEX_SHIFT ) | ARM_SECTION_C | ARM_SECTION_B )
#define ARM_SECTION_NONSHAREABLE_DEVICE ( 0x2 << ARM_SECTION_TEX_SHIFT )
// permissions values for section entries
#define ARM_SECTION_NO_ACCESS 0
#define ARM_SECTION_PRIV_ACCESS_ONLY ( 0x1 << ARM_SECTION_AP10_SHIFT)
#define ARM_SECTION_USER_READ_ONLY ( 0x2 << ARM_SECTION_AP10_SHIFT)
#define ARM_SECTION_FULL_ACCESS ( 0x3 << ARM_SECTION_AP10_SHIFT)
#define ARM_SECTION_PRIV_READ_ONLY ( ARM_SECTION_AP2 | (0x1 << ARM_SECTION_AP10_SHIFT) )
#define ARM_SECTION_READ_ONLY_DEP ( ARM_SECTION_AP2 | (0x2 << ARM_SECTION_AP10_SHIFT) )
#define ARM_SECTION_READ_ONLY ( ARM_SECTION_AP2 | (0x3 << ARM_SECTION_AP10_SHIFT) )
EFI_STATUS
SectionToGcdAttributes (
IN UINT32 SectionAttributes,
OUT UINT64 *GcdAttributes
)
{
*GcdAttributes = 0;
// determine cacheability attributes
switch(SectionAttributes & ARM_SECTION_CACHEABILITY_MASK) {
case ARM_SECTION_STRONGLY_ORDERED:
*GcdAttributes |= EFI_MEMORY_UC;
break;
case ARM_SECTION_SHAREABLE_DEVICE:
*GcdAttributes |= EFI_MEMORY_UC;
break;
case ARM_SECTION_WRITE_THROUGH:
*GcdAttributes |= EFI_MEMORY_WT;
break;
case ARM_SECTION_WRITE_BACK_NWA:
*GcdAttributes |= EFI_MEMORY_WB;
break;
case ARM_SECTION_NORMAL_UNCACHEABLE:
*GcdAttributes |= EFI_MEMORY_WC;
break;
case ARM_SECTION_WRITE_BACK:
*GcdAttributes |= EFI_MEMORY_WB;
break;
case ARM_SECTION_NONSHAREABLE_DEVICE:
*GcdAttributes |= EFI_MEMORY_UC;
break;
default:
return EFI_UNSUPPORTED;
}
// determine protection attributes
switch(SectionAttributes & ARM_SECTION_RW_PERMISSIONS_MASK) {
case ARM_SECTION_NO_ACCESS: // no read, no write
//*GcdAttributes |= EFI_MEMORY_WP | EFI_MEMORY_RP;
break;
case ARM_SECTION_PRIV_ACCESS_ONLY:
case ARM_SECTION_FULL_ACCESS:
// normal read/write access, do not add additional attributes
break;
// read only cases map to write-protect
case ARM_SECTION_PRIV_READ_ONLY:
case ARM_SECTION_READ_ONLY_DEP:
case ARM_SECTION_READ_ONLY:
*GcdAttributes |= EFI_MEMORY_WP;
break;
default:
return EFI_UNSUPPORTED;
}
// now process eXectue Never attribute
if ((SectionAttributes & ARM_SECTION_XN) != 0 ) {
*GcdAttributes |= EFI_MEMORY_XP;
}
return EFI_SUCCESS;
}
/**
Searches memory descriptors covered by given memory range.
This function searches into the Gcd Memory Space for descriptors
(from StartIndex to EndIndex) that contains the memory range
specified by BaseAddress and Length.
@param MemorySpaceMap Gcd Memory Space Map as array.
@param NumberOfDescriptors Number of descriptors in map.
@param BaseAddress BaseAddress for the requested range.
@param Length Length for the requested range.
@param StartIndex Start index into the Gcd Memory Space Map.
@param EndIndex End index into the Gcd Memory Space Map.
@retval EFI_SUCCESS Search successfully.
@retval EFI_NOT_FOUND The requested descriptors does not exist.
**/
EFI_STATUS
SearchGcdMemorySpaces (
IN EFI_GCD_MEMORY_SPACE_DESCRIPTOR *MemorySpaceMap,
IN UINTN NumberOfDescriptors,
IN EFI_PHYSICAL_ADDRESS BaseAddress,
IN UINT64 Length,
OUT UINTN *StartIndex,
OUT UINTN *EndIndex
)
{
UINTN Index;
*StartIndex = 0;
*EndIndex = 0;
for (Index = 0; Index < NumberOfDescriptors; Index++) {
if (BaseAddress >= MemorySpaceMap[Index].BaseAddress &&
BaseAddress < MemorySpaceMap[Index].BaseAddress + MemorySpaceMap[Index].Length) {
*StartIndex = Index;
}
if (BaseAddress + Length - 1 >= MemorySpaceMap[Index].BaseAddress &&
BaseAddress + Length - 1 < MemorySpaceMap[Index].BaseAddress + MemorySpaceMap[Index].Length) {
*EndIndex = Index;
return EFI_SUCCESS;
}
}
return EFI_NOT_FOUND;
}
/**
Sets the attributes for a specified range in Gcd Memory Space Map.
This function sets the attributes for a specified range in
Gcd Memory Space Map.
@param MemorySpaceMap Gcd Memory Space Map as array
@param NumberOfDescriptors Number of descriptors in map
@param BaseAddress BaseAddress for the range
@param Length Length for the range
@param Attributes Attributes to set
@retval EFI_SUCCESS Memory attributes set successfully
@retval EFI_NOT_FOUND The specified range does not exist in Gcd Memory Space
**/
EFI_STATUS
SetGcdMemorySpaceAttributes (
IN EFI_GCD_MEMORY_SPACE_DESCRIPTOR *MemorySpaceMap,
IN UINTN NumberOfDescriptors,
IN EFI_PHYSICAL_ADDRESS BaseAddress,
IN UINT64 Length,
IN UINT64 Attributes
)
{
EFI_STATUS Status;
UINTN Index;
UINTN StartIndex;
UINTN EndIndex;
EFI_PHYSICAL_ADDRESS RegionStart;
UINT64 RegionLength;
//
// Get all memory descriptors covered by the memory range
//
Status = SearchGcdMemorySpaces (
MemorySpaceMap,
NumberOfDescriptors,
BaseAddress,
Length,
&StartIndex,
&EndIndex
);
if (EFI_ERROR (Status)) {
return Status;
}
//
// Go through all related descriptors and set attributes accordingly
//
for (Index = StartIndex; Index <= EndIndex; Index++) {
if (MemorySpaceMap[Index].GcdMemoryType == EfiGcdMemoryTypeNonExistent) {
continue;
}
//
// Calculate the start and end address of the overlapping range
//
if (BaseAddress >= MemorySpaceMap[Index].BaseAddress) {
RegionStart = BaseAddress;
} else {
RegionStart = MemorySpaceMap[Index].BaseAddress;
}
if (BaseAddress + Length - 1 < MemorySpaceMap[Index].BaseAddress + MemorySpaceMap[Index].Length) {
RegionLength = BaseAddress + Length - RegionStart;
} else {
RegionLength = MemorySpaceMap[Index].BaseAddress + MemorySpaceMap[Index].Length - RegionStart;
}
//
// Set memory attributes according to MTRR attribute and the original attribute of descriptor
//
gDS->SetMemorySpaceAttributes (
RegionStart,
RegionLength,
(MemorySpaceMap[Index].Attributes & ~EFI_MEMORY_CACHETYPE_MASK) | (MemorySpaceMap[Index].Capabilities & Attributes)
);
}
return EFI_SUCCESS;
}
EFI_STATUS
SyncCacheConfig (
IN EFI_CPU_ARCH_PROTOCOL *CpuProtocol
)
{
EFI_STATUS Status;
UINT32 i;
UINT32 Descriptor;
UINT32 SectionAttributes;
EFI_PHYSICAL_ADDRESS NextRegionBase;
UINT64 NextRegionLength;
UINT64 GcdAttributes;
UINT32 NextRegionAttributes = 0;
volatile ARM_FIRST_LEVEL_DESCRIPTOR *FirstLevelTable;
UINTN NumberOfDescriptors;
EFI_GCD_MEMORY_SPACE_DESCRIPTOR *MemorySpaceMap;
DEBUG ((EFI_D_PAGE, "SyncCacheConfig()\n"));
// 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
FirstLevelTable = (ARM_FIRST_LEVEL_DESCRIPTOR *)(ArmGetTranslationTableBaseAddress ());
// iterate through each 1MB descriptor
NextRegionBase = NextRegionLength = 0;
for (i=0; i< FIRST_LEVEL_ENTRY_COUNT; i++) {
// obtain existing descriptor and make sure it contains a valid Base Address even if it is a fault section
Descriptor = FirstLevelTable[i] | (ARM_SECTION_BASE_MASK & (i << ARM_SECTION_BASE_SHIFT));
// extract attributes (cacheability and permissions)
SectionAttributes = Descriptor & 0xDEC;
// do we already have an existing region (or are we about to finish)?
// Skip the first entry, and make sure we close on the last entry
if ( (NextRegionLength > 0) || (i == (FIRST_LEVEL_ENTRY_COUNT-1)) ) {
// attributes are changing, update attributes in GCD
if (SectionAttributes != NextRegionAttributes) {
// convert section entry attributes to GCD bitmask
Status = SectionToGcdAttributes (NextRegionAttributes, &GcdAttributes);
ASSERT_EFI_ERROR (Status);
// update GCD with these changes (this will recurse into our own CpuSetMemoryAttributes below which is OK)
SetGcdMemorySpaceAttributes (MemorySpaceMap, NumberOfDescriptors, NextRegionBase, NextRegionLength, GcdAttributes);
// start on a new region
NextRegionLength = 0;
NextRegionBase = Descriptor & ARM_SECTION_BASE_MASK;
}
}
// starting a new region?
if (NextRegionLength == 0) {
NextRegionAttributes = SectionAttributes;
}
NextRegionLength += ARM_PAGE_DESC_ENTRY_MVA_SIZE;
} // section entry loop
return EFI_SUCCESS;
}
EFI_STATUS
UpdatePageEntries (
IN EFI_PHYSICAL_ADDRESS BaseAddress,
IN UINT64 Length,
IN UINT64 Attributes,
IN EFI_PHYSICAL_ADDRESS VirtualMask
)
{
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 = ARM_PAGE_DESC_TYPE_MASK;
EntryValue = ARM_PAGE_TYPE_SMALL;
// Although the PI spec is unclear on this the GCD guarantees that only
// one Attribute bit is set at a time, so we can safely use a switch statement
switch (Attributes) {
case EFI_MEMORY_UC:
// modify cacheability attributes
EntryMask |= ARM_SMALL_PAGE_TEX_MASK | ARM_PAGE_C | ARM_PAGE_B;
// map to strongly ordered
EntryValue |= 0; // TEX[2:0] = 0, C=0, B=0
break;
case EFI_MEMORY_WC:
// modify cacheability attributes
EntryMask |= ARM_SMALL_PAGE_TEX_MASK | ARM_PAGE_C | ARM_PAGE_B;
// map to normal non-cachable
EntryValue |= (0x1 << ARM_SMALL_PAGE_TEX_SHIFT); // TEX [2:0]= 001 = 0x2, B=0, C=0
break;
case EFI_MEMORY_WT:
// modify cacheability attributes
EntryMask |= ARM_SMALL_PAGE_TEX_MASK | ARM_PAGE_C | ARM_PAGE_B;
// write through with no-allocate
EntryValue |= ARM_PAGE_C; // TEX [2:0] = 0, C=1, B=0
break;
case EFI_MEMORY_WB:
// modify cacheability attributes
EntryMask |= ARM_SMALL_PAGE_TEX_MASK | ARM_PAGE_C | ARM_PAGE_B;
// write back (with allocate)
EntryValue |= (0x1 << ARM_SMALL_PAGE_TEX_SHIFT) | ARM_PAGE_C | ARM_PAGE_B; // TEX [2:0] = 001, C=1, B=1
break;
case EFI_MEMORY_WP:
case EFI_MEMORY_XP:
case EFI_MEMORY_UCE:
// cannot be implemented UEFI definition unclear for ARM
// Cause a page fault if these ranges are accessed.
EntryValue = ARM_PAGE_TYPE_FAULT;
DEBUG ((EFI_D_PAGE, "SetMemoryAttributes(): setting page %lx with unsupported attribute %x will page fault on access\n", BaseAddress, Attributes));
break;
default:
return EFI_UNSUPPORTED;
}
// obtain page table base
FirstLevelTable = (ARM_FIRST_LEVEL_DESCRIPTOR *)ArmGetTranslationTableBaseAddress ();
// calculate number of 4KB page table entries to change
NumPageEntries = Length/SIZE_4KB;
// 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 = ((BaseAddress + Offset) & ARM_SECTION_BASE_MASK) >> ARM_SECTION_BASE_SHIFT;
ASSERT (FirstLevelIdx < FIRST_LEVEL_ENTRY_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 ((Descriptor & ARM_DESC_TYPE_MASK) != ARM_DESC_TYPE_PAGE_TABLE ) {
Status = ConvertSectionToPages (FirstLevelIdx << ARM_SECTION_BASE_SHIFT);
if (EFI_ERROR(Status)) {
// exit for loop
break;
}
// re-read descriptor
Descriptor = FirstLevelTable[FirstLevelIdx];
}
// obtain page table base address
PageTable = (ARM_PAGE_TABLE_ENTRY *)(Descriptor & ARM_SMALL_PAGE_BASE_MASK);
// calculate index into the page table
PageTableIndex = ((BaseAddress + Offset) & ARM_SMALL_PAGE_INDEX_MASK) >> ARM_SMALL_PAGE_BASE_SHIFT;
ASSERT (PageTableIndex < SMALL_PAGE_TABLE_ENTRY_COUNT);
// get the entry
CurrentPageTableEntry = PageTable[PageTableIndex];
// mask off appropriate fields
PageTableEntry = CurrentPageTableEntry & ~EntryMask;
// mask in new attributes and/or permissions
PageTableEntry |= EntryValue;
if (VirtualMask != 0) {
// Make this virtual address point at a physical page
PageTableEntry &= ~VirtualMask;
}
if (CurrentPageTableEntry != PageTableEntry) {
Mva = (VOID *)(UINTN)((((UINTN)FirstLevelIdx) << ARM_SECTION_BASE_SHIFT) + (PageTableIndex << ARM_SMALL_PAGE_BASE_SHIFT));
if ((CurrentPageTableEntry & ARM_PAGE_C) == ARM_PAGE_C) {
// The current section mapping is cacheable so Clean/Invalidate the MVA of the page
// Note assumes switch(Attributes), not ARMv7 possibilities
WriteBackInvalidateDataCacheRange (Mva, SIZE_4KB);
}
// Only need to update if we are changing the entry
PageTable[PageTableIndex] = PageTableEntry;
ArmUpdateTranslationTableEntry ((VOID *)&PageTable[PageTableIndex], Mva);
}
Status = EFI_SUCCESS;
Offset += SIZE_4KB;
} // end first level translation table loop
return Status;
}
EFI_STATUS
UpdateSectionEntries (
IN EFI_PHYSICAL_ADDRESS BaseAddress,
IN UINT64 Length,
IN UINT64 Attributes,
IN EFI_PHYSICAL_ADDRESS VirtualMask
)
{
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 = ARM_DESC_TYPE_MASK;
EntryValue = ARM_DESC_TYPE_SECTION;
// Although the PI spec is unclear on this the GCD guarantees that only
// one Attribute bit is set at a time, so we can safely use a switch statement
switch(Attributes) {
case EFI_MEMORY_UC:
// modify cacheability attributes
EntryMask |= ARM_SECTION_CACHEABILITY_MASK;
// map to strongly ordered
EntryValue |= 0; // TEX[2:0] = 0, C=0, B=0
break;
case EFI_MEMORY_WC:
// modify cacheability attributes
EntryMask |= ARM_SECTION_CACHEABILITY_MASK;
// map to normal non-cachable
EntryValue |= (0x1 << ARM_SECTION_TEX_SHIFT); // TEX [2:0]= 001 = 0x2, B=0, C=0
break;
case EFI_MEMORY_WT:
// modify cacheability attributes
EntryMask |= ARM_SECTION_CACHEABILITY_MASK;
// write through with no-allocate
EntryValue |= ARM_SECTION_C; // TEX [2:0] = 0, C=1, B=0
break;
case EFI_MEMORY_WB:
// modify cacheability attributes
EntryMask |= ARM_SECTION_CACHEABILITY_MASK;
// write back (with allocate)
EntryValue |= (0x1 << ARM_SECTION_TEX_SHIFT) | ARM_SECTION_C | ARM_SECTION_B; // TEX [2:0] = 001, C=1, B=1
break;
case EFI_MEMORY_WP:
case EFI_MEMORY_XP:
case EFI_MEMORY_RP:
case EFI_MEMORY_UCE:
// cannot be implemented UEFI definition unclear for ARM
// Cause a page fault if these ranges are accessed.
EntryValue = ARM_DESC_TYPE_FAULT;
DEBUG ((EFI_D_PAGE, "SetMemoryAttributes(): setting section %lx with unsupported attribute %x will page fault on access\n", BaseAddress, Attributes));
break;
default:
return EFI_UNSUPPORTED;
}
// obtain page table base
FirstLevelTable = (ARM_FIRST_LEVEL_DESCRIPTOR *)ArmGetTranslationTableBaseAddress ();
// calculate index into first level translation table for start of modification
FirstLevelIdx = (BaseAddress & ARM_SECTION_BASE_MASK) >> ARM_SECTION_BASE_SHIFT;
ASSERT (FirstLevelIdx < FIRST_LEVEL_ENTRY_COUNT);
// calculate number of 1MB first level entries this applies to
NumSections = Length / ARM_PAGE_DESC_ENTRY_MVA_SIZE;
// iterate through each descriptor
for(i=0; i<NumSections; i++) {
CurrentDescriptor = FirstLevelTable[FirstLevelIdx + i];
// has this descriptor already been coverted to pages?
if ((CurrentDescriptor & ARM_DESC_TYPE_MASK) != ARM_DESC_TYPE_PAGE_TABLE ) {
// forward this 1MB range to page table function instead
Status = UpdatePageEntries ((FirstLevelIdx + i) << ARM_SECTION_BASE_SHIFT, ARM_PAGE_DESC_ENTRY_MVA_SIZE, Attributes, VirtualMask);
} else {
// still a section entry
// mask off appropriate fields
Descriptor = CurrentDescriptor & ~EntryMask;
// mask in new attributes and/or permissions
Descriptor |= EntryValue;
if (VirtualMask != 0) {
Descriptor &= ~VirtualMask;
}
if (CurrentDescriptor != Descriptor) {
Mva = (VOID *)(UINTN)(((UINTN)FirstLevelTable) << ARM_SECTION_BASE_SHIFT);
if ((CurrentDescriptor & ARM_SECTION_C) == ARM_SECTION_C) {
// The current section mapping is cacheable so Clean/Invalidate the MVA of the section
// Note assumes switch(Attributes), not ARMv7 possabilities
WriteBackInvalidateDataCacheRange (Mva, SIZE_1MB);
}
// 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
ConvertSectionToPages (
IN EFI_PHYSICAL_ADDRESS BaseAddress
)
{
EFI_STATUS Status;
EFI_PHYSICAL_ADDRESS PageTableAddr;
UINT32 FirstLevelIdx;
UINT32 SectionDescriptor;
UINT32 PageTableDescriptor;
UINT32 PageDescriptor;
UINT32 i;
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 *)ArmGetTranslationTableBaseAddress ();
// calculate index into first level translation table for start of modification
FirstLevelIdx = (BaseAddress & ARM_SECTION_BASE_MASK) >> ARM_SECTION_BASE_SHIFT;
ASSERT (FirstLevelIdx < FIRST_LEVEL_ENTRY_COUNT);
// get section attributes and convert to page attributes
SectionDescriptor = FirstLevelTable[FirstLevelIdx];
PageDescriptor = ARM_PAGE_TYPE_SMALL;
PageDescriptor |= ((SectionDescriptor & ARM_SECTION_TEX_MASK) >> ARM_SECTION_TEX_SHIFT) << ARM_SMALL_PAGE_TEX_SHIFT;
if ((SectionDescriptor & ARM_SECTION_B) != 0) {
PageDescriptor |= ARM_PAGE_B;
}
if ((SectionDescriptor & ARM_SECTION_C) != 0) {
PageDescriptor |= ARM_PAGE_C;
}
PageDescriptor |= ((SectionDescriptor & ARM_SECTION_AP10_MASK) >> ARM_SECTION_AP10_SHIFT) << ARM_PAGE_AP10_SHIFT;
if ((SectionDescriptor & ARM_SECTION_AP2) != 0) {
PageDescriptor |= ARM_PAGE_AP2;
}
if ((SectionDescriptor & ARM_SECTION_XN) != 0) {
PageDescriptor |= ARM_PAGE_TYPE_SMALL_XN;
}
if ((SectionDescriptor & ARM_SECTION_nG) != 0) {
PageDescriptor |= ARM_PAGE_nG;
}
if ((SectionDescriptor & ARM_SECTION_S) != 0) {
PageDescriptor |= ARM_PAGE_S;
}
// allocate a page table for the 4KB entries (we use up a full page even though we only need 1KB)
Status = gBS->AllocatePages (AllocateAnyPages, EfiBootServicesData, 1, &PageTableAddr);
if (EFI_ERROR(Status)) {
return Status;
}
PageTable = (volatile ARM_PAGE_TABLE_ENTRY *)(UINTN)PageTableAddr;
// write the page table entries out
for (i=0; i<(ARM_PAGE_DESC_ENTRY_MVA_SIZE/SIZE_4KB); i++) {
PageTable[i] = ((BaseAddress + (i << 12)) & ARM_SMALL_PAGE_BASE_MASK) | PageDescriptor;
}
// flush d-cache so descriptors make it back to uncached memory for subsequent table walks
WriteBackInvalidateDataCacheRange ((VOID *)(UINTN)PageTableAddr, SIZE_4KB);
// formulate page table entry, Domain=0, NS=0
PageTableDescriptor = (((UINTN)PageTableAddr) & ARM_PAGE_DESC_BASE_MASK) | ARM_DESC_TYPE_PAGE_TABLE;
// write the page table entry out, repalcing section entry
FirstLevelTable[FirstLevelIdx] = PageTableDescriptor;
return EFI_SUCCESS;
}
EFI_STATUS
SetMemoryAttributes (
IN EFI_PHYSICAL_ADDRESS BaseAddress,
IN UINT64 Length,
IN UINT64 Attributes,
IN EFI_PHYSICAL_ADDRESS VirtualMask
)
{
EFI_STATUS Status;
if(((BaseAddress & 0xFFFFF) == 0) && ((Length & 0xFFFFF) == 0)) {
// is the base and length a multiple of 1 MB?
DEBUG ((EFI_D_PAGE, "SetMemoryAttributes(): MMU section 0x%x length 0x%x to %lx\n", (UINTN)BaseAddress, (UINTN)Length, Attributes));
Status = UpdateSectionEntries (BaseAddress, Length, Attributes, VirtualMask);
} else {
// base and/or length is not a multiple of 1 MB
DEBUG ((EFI_D_PAGE, "SetMemoryAttributes(): MMU page 0x%x length 0x%x to %lx\n", (UINTN)BaseAddress, (UINTN)Length, Attributes));
Status = UpdatePageEntries (BaseAddress, Length, Attributes, VirtualMask);
}
// flush d-cache so descriptors make it back to uncached memory for subsequent table walks
// flush and invalidate pages
ArmCleanInvalidateDataCache ();
ArmInvalidateInstructionCache ();
// invalidate all TLB entries so changes are synced
ArmInvalidateTlb ();
return Status;
}
/**
This function modifies the attributes for the memory region specified by BaseAddress and
Length from their current attributes to the attributes specified by Attributes.
@param This The EFI_CPU_ARCH_PROTOCOL instance.
@param BaseAddress The physical address that is the start address of a memory region.
@param Length The size in bytes of the memory region.
@param Attributes The bit mask of attributes to set for the memory region.
@retval EFI_SUCCESS The attributes were set for the memory region.
@retval EFI_ACCESS_DENIED The attributes for the memory resource range specified by
BaseAddress and Length cannot be modified.
@retval EFI_INVALID_PARAMETER Length is zero.
@retval EFI_OUT_OF_RESOURCES There are not enough system resources to modify the attributes of
the memory resource range.
@retval EFI_UNSUPPORTED The processor does not support one or more bytes of the memory
resource range specified by BaseAddress and Length.
The bit mask of attributes is not support for the memory resource
range specified by BaseAddress and Length.
**/
EFI_STATUS
EFIAPI
CpuSetMemoryAttributes (
IN EFI_CPU_ARCH_PROTOCOL *This,
IN EFI_PHYSICAL_ADDRESS BaseAddress,
IN UINT64 Length,
IN UINT64 Attributes
)
{
DEBUG ((EFI_D_PAGE, "SetMemoryAttributes(%lx, %lx, %lx)\n", BaseAddress, Length, Attributes));
if ( ((BaseAddress & (SIZE_4KB-1)) != 0) || ((Length & (SIZE_4KB-1)) != 0)){
// minimum granularity is SIZE_4KB (4KB on ARM)
DEBUG ((EFI_D_PAGE, "SetMemoryAttributes(%lx, %lx, %lx): minimum ganularity is SIZE_4KB\n", BaseAddress, Length, Attributes));
return EFI_UNSUPPORTED;
}
return SetMemoryAttributes (BaseAddress, Length, Attributes, 0);
}
//
// Add a new protocol to support
//
EFI_STATUS
EFIAPI
CpuConvertPagesToUncachedVirtualAddress (
IN VIRTUAL_UNCACHED_PAGES_PROTOCOL *This,
IN EFI_PHYSICAL_ADDRESS Address,
IN UINTN Length,
IN EFI_PHYSICAL_ADDRESS VirtualMask,
OUT UINT64 *Attributes OPTIONAL
)
{
EFI_STATUS Status;
EFI_GCD_MEMORY_SPACE_DESCRIPTOR GcdDescriptor;
if (Attributes != NULL) {
Status = gDS->GetMemorySpaceDescriptor (Address, &GcdDescriptor);
if (!EFI_ERROR (Status)) {
*Attributes = GcdDescriptor.Attributes;
}
}
//
// Make this address range page fault if accessed. If it is a DMA buffer than this would
// be the PCI address. Code should always use the CPU address, and we will or in VirtualMask
// to that address.
//
Status = SetMemoryAttributes (Address, Length, EFI_MEMORY_WP, 0);
if (!EFI_ERROR (Status)) {
Status = SetMemoryAttributes (Address | VirtualMask, Length, EFI_MEMORY_UC, VirtualMask);
}
DEBUG ((DEBUG_INFO | DEBUG_LOAD, "ConvertPagesToUncachedVirtualAddress()\n Unmapped 0x%08lx Mapped 0x%08lx 0x%x bytes\n", Address, Address | VirtualMask, Length));
return Status;
}
EFI_STATUS
EFIAPI
CpuReconvertPages (
IN VIRTUAL_UNCACHED_PAGES_PROTOCOL *This,
IN EFI_PHYSICAL_ADDRESS Address,
IN UINTN Length,
IN EFI_PHYSICAL_ADDRESS VirtualMask,
IN UINT64 Attributes
)
{
EFI_STATUS Status;
DEBUG ((DEBUG_INFO | DEBUG_LOAD, "CpuReconvertPages(%lx, %x, %lx, %lx)\n", Address, Length, VirtualMask, Attributes));
//
// Unmap the alaised Address
//
Status = SetMemoryAttributes (Address | VirtualMask, Length, EFI_MEMORY_WP, 0);
if (!EFI_ERROR (Status)) {
//
// Restore atttributes
//
Status = SetMemoryAttributes (Address, Length, Attributes, 0);
}
return Status;
}
VIRTUAL_UNCACHED_PAGES_PROTOCOL gVirtualUncachedPages = {
CpuConvertPagesToUncachedVirtualAddress,
CpuReconvertPages
};