From c4add6b6e971e0bb3f276ed3636a083e782e96cc Mon Sep 17 00:00:00 2001
From: Laszlo Ersek <lersek@redhat.com>
Date: Thu, 17 May 2018 21:51:11 +0200
Subject: [PATCH] ArmVirtPkg/PlatformBootManagerLib: connect Virtio RNG devices
again
Virtio RNG devices are never boot devices, so in commit ff1d0fbfbaec we
stopped connecting them. This is a problem because an OS boot loader may
depend on EFI_RNG_PROTOCOL to seed the OS's RNG.
Connect Virtio RNG devices again. And, while commit ff1d0fbfbaec removed
that from PlatformBootManagerAfterConsole(), reintroduce it now to
PlatformBootManagerBeforeConsole() -- this way Driver#### options launched
between both functions may access EFI_RNG_PROTOCOL too.
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Fixes: ff1d0fbfbaec55038ccf888759588fa4e21516f4
Ref: https://bugzilla.redhat.com/show_bug.cgi?id=1579518
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
.../PlatformBootManagerLib.inf | 1 +
.../PlatformBootManagerLib/PlatformBm.c | 129 ++++++++++++++++++
2 files changed, 130 insertions(+)
diff --git a/ArmVirtPkg/Library/PlatformBootManagerLib/PlatformBootManagerLib.inf b/ArmVirtPkg/Library/PlatformBootManagerLib/PlatformBootManagerLib.inf
index 1e22f8bb38..d6c1ef95dc 100644
--- a/ArmVirtPkg/Library/PlatformBootManagerLib/PlatformBootManagerLib.inf
+++ b/ArmVirtPkg/Library/PlatformBootManagerLib/PlatformBootManagerLib.inf
@@ -83,3 +83,4 @@ [Protocols]
gEfiLoadedImageProtocolGuid
gEfiPciRootBridgeIoProtocolGuid
gEfiSimpleFileSystemProtocolGuid
+ gVirtioDeviceProtocolGuid
diff --git a/ArmVirtPkg/Library/PlatformBootManagerLib/PlatformBm.c b/ArmVirtPkg/Library/PlatformBootManagerLib/PlatformBm.c
index 5d5e51d8c8..62cce6a01e 100644
--- a/ArmVirtPkg/Library/PlatformBootManagerLib/PlatformBm.c
+++ b/ArmVirtPkg/Library/PlatformBootManagerLib/PlatformBm.c
@@ -16,6 +16,7 @@
**/
#include <IndustryStandard/Pci22.h>
+#include <IndustryStandard/Virtio095.h>
#include <Library/BootLogoLib.h>
#include <Library/DevicePathLib.h>
#include <Library/PcdLib.h>
@@ -27,6 +28,7 @@
#include <Protocol/LoadedImage.h>
#include <Protocol/PciIo.h>
#include <Protocol/PciRootBridgeIo.h>
+#include <Protocol/VirtioDevice.h>
#include <Guid/EventGroup.h>
#include <Guid/RootBridgesConnectedEventGroup.h>
@@ -260,6 +262,121 @@ IsPciDisplay (
}
+/**
+ This FILTER_FUNCTION checks if a handle corresponds to a Virtio RNG device at
+ the VIRTIO_DEVICE_PROTOCOL level.
+**/
+STATIC
+BOOLEAN
+EFIAPI
+IsVirtioRng (
+ IN EFI_HANDLE Handle,
+ IN CONST CHAR16 *ReportText
+ )
+{
+ EFI_STATUS Status;
+ VIRTIO_DEVICE_PROTOCOL *VirtIo;
+
+ Status = gBS->HandleProtocol (Handle, &gVirtioDeviceProtocolGuid,
+ (VOID**)&VirtIo);
+ if (EFI_ERROR (Status)) {
+ return FALSE;
+ }
+ return (BOOLEAN)(VirtIo->SubSystemDeviceId ==
+ VIRTIO_SUBSYSTEM_ENTROPY_SOURCE);
+}
+
+
+/**
+ This FILTER_FUNCTION checks if a handle corresponds to a Virtio RNG device at
+ the EFI_PCI_IO_PROTOCOL level.
+**/
+STATIC
+BOOLEAN
+EFIAPI
+IsVirtioPciRng (
+ IN EFI_HANDLE Handle,
+ IN CONST CHAR16 *ReportText
+ )
+{
+ EFI_STATUS Status;
+ EFI_PCI_IO_PROTOCOL *PciIo;
+ UINT16 VendorId;
+ UINT16 DeviceId;
+ UINT8 RevisionId;
+ BOOLEAN Virtio10;
+ UINT16 SubsystemId;
+
+ Status = gBS->HandleProtocol (Handle, &gEfiPciIoProtocolGuid,
+ (VOID**)&PciIo);
+ if (EFI_ERROR (Status)) {
+ return FALSE;
+ }
+
+ //
+ // Read and check VendorId.
+ //
+ Status = PciIo->Pci.Read (PciIo, EfiPciIoWidthUint16, PCI_VENDOR_ID_OFFSET,
+ 1, &VendorId);
+ if (EFI_ERROR (Status)) {
+ goto PciError;
+ }
+ if (VendorId != VIRTIO_VENDOR_ID) {
+ return FALSE;
+ }
+
+ //
+ // Read DeviceId and RevisionId.
+ //
+ Status = PciIo->Pci.Read (PciIo, EfiPciIoWidthUint16, PCI_DEVICE_ID_OFFSET,
+ 1, &DeviceId);
+ if (EFI_ERROR (Status)) {
+ goto PciError;
+ }
+ Status = PciIo->Pci.Read (PciIo, EfiPciIoWidthUint8, PCI_REVISION_ID_OFFSET,
+ 1, &RevisionId);
+ if (EFI_ERROR (Status)) {
+ goto PciError;
+ }
+
+ //
+ // From DeviceId and RevisionId, determine whether the device is a
+ // modern-only Virtio 1.0 device. In case of Virtio 1.0, DeviceId can
+ // immediately be restricted to VIRTIO_SUBSYSTEM_ENTROPY_SOURCE, and
+ // SubsystemId will only play a sanity-check role. Otherwise, DeviceId can
+ // only be sanity-checked, and SubsystemId will decide.
+ //
+ if (DeviceId == 0x1040 + VIRTIO_SUBSYSTEM_ENTROPY_SOURCE &&
+ RevisionId >= 0x01) {
+ Virtio10 = TRUE;
+ } else if (DeviceId >= 0x1000 && DeviceId <= 0x103F && RevisionId == 0x00) {
+ Virtio10 = FALSE;
+ } else {
+ return FALSE;
+ }
+
+ //
+ // Read and check SubsystemId as dictated by Virtio10.
+ //
+ Status = PciIo->Pci.Read (PciIo, EfiPciIoWidthUint16,
+ PCI_SUBSYSTEM_ID_OFFSET, 1, &SubsystemId);
+ if (EFI_ERROR (Status)) {
+ goto PciError;
+ }
+ if (Virtio10 && SubsystemId >= 0x40) {
+ return TRUE;
+ }
+ if (!Virtio10 && SubsystemId == VIRTIO_SUBSYSTEM_ENTROPY_SOURCE) {
+ return TRUE;
+ }
+ return FALSE;
+
+PciError:
+ DEBUG ((DEBUG_ERROR, "%a: %s: %r\n", __FUNCTION__, ReportText, Status));
+ return FALSE;
+}
+
+
/**
This CALLBACK_FUNCTION attempts to connect a handle non-recursively, asking
the matching driver to produce all first-level child handles.
@@ -644,6 +761,18 @@ PlatformBootManagerBeforeConsole (
// Register platform-specific boot options and keyboard shortcuts.
//
PlatformRegisterOptionsAndKeys ();
+
+ //
+ // At this point, VIRTIO_DEVICE_PROTOCOL instances exist only for Virtio MMIO
+ // transports. Install EFI_RNG_PROTOCOL instances on Virtio MMIO RNG devices.
+ //
+ FilterAndProcess (&gVirtioDeviceProtocolGuid, IsVirtioRng, Connect);
+
+ //
+ // Install both VIRTIO_DEVICE_PROTOCOL and (dependent) EFI_RNG_PROTOCOL
+ // instances on Virtio PCI RNG devices.
+ //
+ FilterAndProcess (&gEfiPciIoProtocolGuid, IsVirtioPciRng, Connect);
}
/**
--
2.17.0