On 2/27/2018 10:09 AM, Heyi Guo wrote:
PCI address translation is necessary for some non-x86 platforms. On
such platforms, address value (denoted as "device address" or "address
in PCI view") set to PCI BAR registers in configuration space might be
different from the address which is used by CPU to access the
registers in memory BAR or IO BAR spaces (denoted as "host address" or
"address in CPU view"). The difference between the two addresses is
called "Address Translation Offset" or simply "translation", and can
be represented by "Address Translation Offset" in ACPI QWORD Address
Space Descriptor (Offset 0x1E). However UEFI and ACPI differs on the
definitions of QWORD Address Space Descriptor, and we will follow UEFI
definition on UEFI protocols, such as PCI root bridge IO protocol and
PCI IO protocol. In UEFI 2.7, "Address Translation Offset" is "Offset
to apply to the Starting address to convert it to a PCI address". This
means:
1. Translation = device address - host address.
2. PciRootBridgeIo->Configuration should return CPU view address, as
well as PciIo->GetBarAttributes.
Summary of addresses used:
1. Base and Limit in PCI_ROOT_BRIDGE_APERTURE are device address, for
it is easy to check whether the address is below 4G or above 4G.
2. Address returned by
EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL::GetProposedResources
is device address, or else PCI bus driver cannot set correct address
into PCI BAR registers.
3. Address returned by PciRootBridgeIo->Configuration is host address
per UEFI 2.7 definition.
4. Addresses used in GCD manipulation are host address.
5. Addresses in ResAllocNode of PCI_ROOT_BRIDGE_INSTANCE are host
address, for they are allocated from GCD.
6. Address passed to PciHostBridgeResourceConflict is host address,
for it comes from ResAllocNode.
RESTRICTION: to simplify the situation, we require the alignment of
Translation must be larger than any BAR alignment in the same root
bridge, so that resource allocation alignment can be applied to both
device address and host address.
(1). I'd like to see this restriction be reflected in code.
Both assertion and if-check are needed to ensure debug firmware hang
and release firmware return fail status from PciHostBridge driver.
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Heyi Guo <heyi....@linaro.org>
Cc: Ruiyu Ni <ruiyu...@intel.com>
Cc: Ard Biesheuvel <ard.biesheu...@linaro.org>
Cc: Star Zeng <star.z...@intel.com>
Cc: Eric Dong <eric.d...@intel.com>
Cc: Laszlo Ersek <ler...@redhat.com>
Cc: Michael D Kinney <michael.d.kin...@intel.com>
---
Notes:
v4:
- Add ASSERT (FALSE) to default branch in GetTranslationByResourceType
[Laszlo]
- Fix bug when passing BaseAddress to gDS->AllocateIoSpace and
gDS->AllocateMemorySpace [Laszlo]
- Add comment for applying alignment to both device address and host
address, and add NOTE for the alignment requirement of Translation,
as well as in commit message [Laszlo][Ray]
- Improve indention for the code in CreateRootBridge [Laszlo]
- Improve comment for Translation in PCI_ROOT_BRIDGE_APERTURE
definition [Laszlo]
- Ignore translation of bus in CreateRootBridge
MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostResource.h | 2 +
MdeModulePkg/Include/Library/PciHostBridgeLib.h | 14 +++
MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c | 85 +++++++++++---
MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciRootBridgeIo.c | 122
+++++++++++++++++---
4 files changed, 194 insertions(+), 29 deletions(-)
diff --git a/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostResource.h
b/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostResource.h
index 8612c0c3251b..662c2dd59529 100644
--- a/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostResource.h
+++ b/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostResource.h
@@ -38,6 +38,8 @@ typedef enum {
typedef struct {
PCI_RESOURCE_TYPE Type;
+ // Base is a host address instead of a device address when address
translation
+ // exists and host address != device address
(2). Coding style issue. The comments need to be in style like:
//[EMPTY]
// xxxx
//[EMPTY]
And how about just simply say Base is a host address. No matter address
translation exists or not, Base is a host address actually.
UINT64 Base;
UINT64 Length;
UINT64 Alignment;
diff --git a/MdeModulePkg/Include/Library/PciHostBridgeLib.h
b/MdeModulePkg/Include/Library/PciHostBridgeLib.h
index d42e9ecdd763..c842a4152e85 100644
--- a/MdeModulePkg/Include/Library/PciHostBridgeLib.h
+++ b/MdeModulePkg/Include/Library/PciHostBridgeLib.h
@@ -20,8 +20,22 @@
// (Base > Limit) indicates an aperture is not available.
//
typedef struct {
+ // Base and Limit are the device address instead of host address when
+ // Translation is not zero
(3). Similar comments to (2).
UINT64 Base;
UINT64 Limit;
+ // According to UEFI 2.7, Device Address = Host Address + Translation,
+ // so Translation = Device Address - Host Address.
+ // On platforms where Translation is not zero, the subtraction is probably to
+ // be performed with UINT64 wrap-around semantics, for we may translate an
+ // above-4G host address into a below-4G device address for legacy PCIe
device
+ // compatibility.
+ // NOTE: The alignment of Translation is required to be larger than any BAR
+ // alignment in the same root bridge, so that the same alignment can be
+ // applied to both device address and host address, which simplifies the
+ // situation and makes the current resource allocation code in generic PCI
+ // host bridge driver still work.
(4). Still I'd like to see the alignment requirement be reflected in code
through assertion and if-check.
+ UINT64 Translation;
} PCI_ROOT_BRIDGE_APERTURE;
typedef struct {
diff --git a/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c
b/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c
index 1494848c3e8c..1e65faee9084 100644
--- a/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c
+++ b/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c
@@ -32,6 +32,30 @@ EDKII_IOMMU_PROTOCOL *mIoMmuProtocol;
EFI_EVENT mIoMmuEvent;
VOID *mIoMmuRegistration;
+STATIC
(5). Can you remove STATIC? personal preference:)
+UINT64
+GetTranslationByResourceType (
+ IN PCI_ROOT_BRIDGE_INSTANCE *RootBridge,
+ IN PCI_RESOURCE_TYPE ResourceType
+ )
+{
+ switch (ResourceType) {
+ case TypeIo:
+ return RootBridge->Io.Translation;
+ case TypeMem32:
+ return RootBridge->Mem.Translation;
+ case TypePMem32:
+ return RootBridge->PMem.Translation;
+ case TypeMem64:
+ return RootBridge->MemAbove4G.Translation;
+ case TypePMem64:
+ return RootBridge->PMemAbove4G.Translation;
+ default:
+ ASSERT (FALSE);
+ return 0;
+ }
+}
+
/**
Ensure the compatibility of an IO space descriptor with the IO aperture.
@@ -366,6 +390,7 @@ InitializePciHostBridge (
UINTN MemApertureIndex;
BOOLEAN ResourceAssigned;
LIST_ENTRY *Link;
+ UINT64 TempHostAddress;
(6). Just use name HostAddress?
RootBridges = PciHostBridgeGetRootBridges (&RootBridgeCount);
if ((RootBridges == NULL) || (RootBridgeCount == 0)) {
@@ -411,18 +436,24 @@ InitializePciHostBridge (
}
if (RootBridges[Index].Io.Base <= RootBridges[Index].Io.Limit) {
+ // Base and Limit in PCI_ROOT_BRIDGE_APERTURE are device address.
+ // According to UEFI 2.7, device address = host address + Translation.
+ // For GCD resource manipulation, we should use host address, so
+ // Translation is subtracted from device address here.
(7). Please adjust the comment style to have two EMPTY line of comment above
and below. Same to all comments in the patch.
Status = AddIoSpace (
- RootBridges[Index].Io.Base,
+ RootBridges[Index].Io.Base -
RootBridges[Index].Io.Translation,
RootBridges[Index].Io.Limit - RootBridges[Index].Io.Base + 1
);
ASSERT_EFI_ERROR (Status);
if (ResourceAssigned) {
+ TempHostAddress = RootBridges[Index].Io.Base -
+ RootBridges[Index].Io.Translation;
Status = gDS->AllocateIoSpace (
EfiGcdAllocateAddress,
EfiGcdIoTypeIo,
0,
RootBridges[Index].Io.Limit -
RootBridges[Index].Io.Base + 1,
- &RootBridges[Index].Io.Base,
+ &TempHostAddress,
gImageHandle,
NULL
);
@@ -443,14 +474,18 @@ InitializePciHostBridge (
for (MemApertureIndex = 0; MemApertureIndex < ARRAY_SIZE (MemApertures);
MemApertureIndex++) {
if (MemApertures[MemApertureIndex]->Base <=
MemApertures[MemApertureIndex]->Limit) {
+ // Base and Limit in PCI_ROOT_BRIDGE_APERTURE are device address.
+ // According to UEFI 2.7, device address = host address + Translation.
+ // For GCD resource manipulation, we should use host address, so
+ // Translation is subtracted from device address here.
Status = AddMemoryMappedIoSpace (
- MemApertures[MemApertureIndex]->Base,
+ MemApertures[MemApertureIndex]->Base -
MemApertures[MemApertureIndex]->Translation,
MemApertures[MemApertureIndex]->Limit -
MemApertures[MemApertureIndex]->Base + 1,
EFI_MEMORY_UC
);
ASSERT_EFI_ERROR (Status);
Status = gDS->SetMemorySpaceAttributes (
- MemApertures[MemApertureIndex]->Base,
+ MemApertures[MemApertureIndex]->Base -
MemApertures[MemApertureIndex]->Translation,
MemApertures[MemApertureIndex]->Limit -
MemApertures[MemApertureIndex]->Base + 1,
EFI_MEMORY_UC
);
@@ -458,12 +493,14 @@ InitializePciHostBridge (
DEBUG ((DEBUG_WARN, "PciHostBridge driver failed to set EFI_MEMORY_UC to
MMIO aperture - %r.\n", Status));
}
if (ResourceAssigned) {
+ TempHostAddress = MemApertures[MemApertureIndex]->Base -
+ MemApertures[MemApertureIndex]->Translation;
Status = gDS->AllocateMemorySpace (
EfiGcdAllocateAddress,
EfiGcdMemoryTypeMemoryMappedIo,
0,
MemApertures[MemApertureIndex]->Limit -
MemApertures[MemApertureIndex]->Base + 1,
- &MemApertures[MemApertureIndex]->Base,
+ &TempHostAddress,
gImageHandle,
NULL
);
@@ -654,6 +691,11 @@ AllocateResource (
if (BaseAddress < Limit) {
//
// Have to make sure Aligment is handled since we are doing direct
address allocation
+ // Strictly speaking, alignment requirement should be applied to device
+ // address instead of host address which is used in GCD manipulation below,
+ // but as we restrict the alignment of Translation to be larger than any
BAR
+ // alignment in the root bridge, we can simplify the situation and consider
+ // the same alignment requirement is also applied to host address.
//
BaseAddress = ALIGN_VALUE (BaseAddress, LShiftU64 (1, BitsOfAlignment));
@@ -824,12 +866,17 @@ NotifyPhase (
switch (Index) {
case TypeIo:
+ // Base and Limit in PCI_ROOT_BRIDGE_APERTURE are device address.
+ // According to UEFI 2.7, device address = host address +
Translation.
+ // For AllocateResource is manipulating GCD resource, we should use
+ // host address here, so Translation is subtracted from Base and
+ // Limit.
BaseAddress = AllocateResource (
FALSE,
RootBridge->ResAllocNode[Index].Length,
MIN (15, BitsOfAlignment),
- ALIGN_VALUE (RootBridge->Io.Base, Alignment + 1),
- RootBridge->Io.Limit
+ ALIGN_VALUE (RootBridge->Io.Base, Alignment + 1) -
RootBridge->Io.Translation,
+ RootBridge->Io.Limit - RootBridge->Io.Translation
);
break;
@@ -838,8 +885,8 @@ NotifyPhase (
(8). Add assertion and if-check here to make sure alignment of Translation
is no less than the Alignment.
TRUE,
RootBridge->ResAllocNode[Index].Length,
MIN (63, BitsOfAlignment),
- ALIGN_VALUE (RootBridge->MemAbove4G.Base,
Alignment + 1),
- RootBridge->MemAbove4G.Limit
+ ALIGN_VALUE (RootBridge->MemAbove4G.Base, Alignment +
1) - RootBridge->MemAbove4G.Translation,
+ RootBridge->MemAbove4G.Limit -
RootBridge->MemAbove4G.Translation
);
if (BaseAddress != MAX_UINT64) {
break;
@@ -853,8 +900,8 @@ NotifyPhase (
TRUE,
RootBridge->ResAllocNode[Index].Length,
MIN (31, BitsOfAlignment),
- ALIGN_VALUE (RootBridge->Mem.Base, Alignment + 1),
- RootBridge->Mem.Limit
+ ALIGN_VALUE (RootBridge->Mem.Base, Alignment + 1) -
RootBridge->Mem.Translation,
+ RootBridge->Mem.Limit - RootBridge->Mem.Translation
);
break;
@@ -863,8 +910,8 @@ NotifyPhase (
TRUE,
RootBridge->ResAllocNode[Index].Length,
MIN (63, BitsOfAlignment),
- ALIGN_VALUE (RootBridge->PMemAbove4G.Base,
Alignment + 1),
- RootBridge->PMemAbove4G.Limit
+ ALIGN_VALUE (RootBridge->PMemAbove4G.Base, Alignment
+ 1) - RootBridge->PMemAbove4G.Translation,
+ RootBridge->PMemAbove4G.Limit -
RootBridge->PMemAbove4G.Translation
);
if (BaseAddress != MAX_UINT64) {
break;
@@ -877,8 +924,8 @@ NotifyPhase (
TRUE,
RootBridge->ResAllocNode[Index].Length,
MIN (31, BitsOfAlignment),
- ALIGN_VALUE (RootBridge->PMem.Base, Alignment + 1),
- RootBridge->PMem.Limit
+ ALIGN_VALUE (RootBridge->PMem.Base, Alignment + 1) -
RootBridge->PMem.Translation,
+ RootBridge->PMem.Limit -
RootBridge->PMem.Translation
);
break;
@@ -1152,6 +1199,7 @@ StartBusEnumeration (
Descriptor->AddrSpaceGranularity = 0;
Descriptor->AddrRangeMin = RootBridge->Bus.Base;
Descriptor->AddrRangeMax = 0;
+ // Ignore translation offset for bus
(9). Per PI spec on StartBusEnumeration, AddrRangeMax is ignored. So I don't
think we need add comments here.
