[PATCH v3 0/5] OvmfPkg/Microvm: second batch of microvm patches

[PATCH v3 0/5] OvmfPkg/Microvm: second batch of microvm patches

[Gerd Hoffmann]

Adds support for virtio-mmio devices to microvm.

While being at it also add the README, the
patch somehow disappeared from the first batch.

v3:
 - uncrustify & rebase to latest master
 - pick up some review tags
 - minor README updates.

v2:
 - qemu changes needed for this are merged and will be
   in the 6.2 release (dec 2021).
 - more verbose commit messages.

Gerd Hoffmann (5):
  OvmfPkg/Microvm/fdt: add device tree support
  OvmfPkg/Microvm/fdt: load fdt from fw_cfg
  OvmfPkg/Microvm/fdt: add empty fdt
  OvmfPkg/Microvm/virtio: add virtio-mmio support
  OvmfPkg/Microvm: add README

 OvmfPkg/Microvm/MicrovmX64.dsc      |  8 ++++
 OvmfPkg/Microvm/MicrovmX64.fdf      |  3 ++
 OvmfPkg/PlatformPei/PlatformPei.inf |  1 +
 OvmfPkg/PlatformPei/Platform.c      | 63 +++++++++++++++++++++++++++++
 OvmfPkg/Microvm/README              | 50 +++++++++++++++++++++++
 5 files changed, 125 insertions(+)
 create mode 100644 OvmfPkg/Microvm/README

-- 
2.33.1

[PATCH v3 1/5] OvmfPkg/Microvm/fdt: add device tree support

[Gerd Hoffmann]

Add fdt parser from EmbeddedPkg (FdtLib and FdtClientDxe) to MicrovmX64.

Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3689
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 OvmfPkg/Microvm/MicrovmX64.dsc | 6 ++++++
 OvmfPkg/Microvm/MicrovmX64.fdf | 2 ++
 2 files changed, 8 insertions(+)

diff --git a/OvmfPkg/Microvm/MicrovmX64.dsc b/OvmfPkg/Microvm/MicrovmX64.dsc
index 5f4d9226791b..edddf6c29b32 100644
--- a/OvmfPkg/Microvm/MicrovmX64.dsc
+++ b/OvmfPkg/Microvm/MicrovmX64.dsc
@@ -232,6 +232,7 @@ [LibraryClasses.common]
   VmgExitLib|OvmfPkg/Library/VmgExitLib/VmgExitLib.inf
   SerialPortLib|MdeModulePkg/Library/BaseSerialPortLib16550/BaseSerialPortLib16550.inf
   PlatformHookLib|MdeModulePkg/Library/BasePlatformHookLibNull/BasePlatformHookLibNull.inf
+  FdtLib|EmbeddedPkg/Library/FdtLib/FdtLib.inf
 
 [LibraryClasses.common.SEC]
   QemuFwCfgLib|OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgSecLib.inf
@@ -739,6 +740,11 @@ [Components]
   #
   MdeModulePkg/Universal/SerialDxe/SerialDxe.inf
 
+  #
+  # device tree
+  #
+  EmbeddedPkg/Drivers/FdtClientDxe/FdtClientDxe.inf
+
   #
   # SMBIOS Support
   #
diff --git a/OvmfPkg/Microvm/MicrovmX64.fdf b/OvmfPkg/Microvm/MicrovmX64.fdf
index 4570bc866c9b..905d23b843d3 100644
--- a/OvmfPkg/Microvm/MicrovmX64.fdf
+++ b/OvmfPkg/Microvm/MicrovmX64.fdf
@@ -276,6 +276,8 @@ [FV.DXEFV]
 INF  MdeModulePkg/Universal/Disk/UdfDxe/UdfDxe.inf
 INF  OvmfPkg/VirtioFsDxe/VirtioFsDxe.inf
 
+INF  EmbeddedPkg/Drivers/FdtClientDxe/FdtClientDxe.inf
+
 !if $(TOOL_CHAIN_TAG) != "XCODE5"
 INF  ShellPkg/DynamicCommand/TftpDynamicCommand/TftpDynamicCommand.inf
 INF  ShellPkg/DynamicCommand/HttpDynamicCommand/HttpDynamicCommand.inf
-- 
2.33.1

[PATCH v3 2/5] OvmfPkg/Microvm/fdt: load fdt from fw_cfg

[Gerd Hoffmann]

Needed for hardware detection: virtio-mmio devices for now,
later also pcie root bridge.

Depends on patched qemu which actually provides an fdt:
https://gitlab.com/kraxel/qemu/-/commits/sirius/microvm-device-tree

https://bugzilla.tianocore.org/show_bug.cgi?id=3689
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 OvmfPkg/PlatformPei/PlatformPei.inf |  1 +
 OvmfPkg/PlatformPei/Platform.c      | 45 +++++++++++++++++++++++++++++
 2 files changed, 46 insertions(+)

diff --git a/OvmfPkg/PlatformPei/PlatformPei.inf b/OvmfPkg/PlatformPei/PlatformPei.inf
index 1c56ba275835..8ef404168c45 100644
--- a/OvmfPkg/PlatformPei/PlatformPei.inf
+++ b/OvmfPkg/PlatformPei/PlatformPei.inf
@@ -44,6 +44,7 @@ [Packages]
 
 [Guids]
   gEfiMemoryTypeInformationGuid
+  gFdtHobGuid
 
 [LibraryClasses]
   BaseLib
diff --git a/OvmfPkg/PlatformPei/Platform.c b/OvmfPkg/PlatformPei/Platform.c
index 906f64615de7..c9ec1d7e99fb 100644
--- a/OvmfPkg/PlatformPei/Platform.c
+++ b/OvmfPkg/PlatformPei/Platform.c
@@ -321,6 +321,50 @@ PciExBarInitialization (
     );
 }
 
+VOID
+MicrovmInitialization (
+  VOID
+  )
+{
+  FIRMWARE_CONFIG_ITEM  FdtItem;
+  UINTN                 FdtSize;
+  UINTN                 FdtPages;
+  EFI_STATUS            Status;
+  UINT64                *FdtHobData;
+  VOID                  *NewBase;
+
+  Status = QemuFwCfgFindFile ("etc/fdt", &FdtItem, &FdtSize);
+  if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_INFO, "%a: no etc/fdt found in fw_cfg\n", __FUNCTION__));
+    return;
+  }
+
+  FdtPages = EFI_SIZE_TO_PAGES (FdtSize);
+  NewBase  = AllocatePages (FdtPages);
+  if (NewBase == NULL) {
+    DEBUG ((DEBUG_INFO, "%a: AllocatePages failed\n", __FUNCTION__));
+    return;
+  }
+
+  QemuFwCfgSelectItem (FdtItem);
+  QemuFwCfgReadBytes (FdtSize, NewBase);
+
+  FdtHobData = BuildGuidHob (&gFdtHobGuid, sizeof (*FdtHobData));
+  if (FdtHobData == NULL) {
+    DEBUG ((DEBUG_INFO, "%a: BuildGuidHob failed\n", __FUNCTION__));
+    return;
+  }
+
+  DEBUG ((
+    DEBUG_INFO,
+    "%a: fdt at 0x%x (size %d)\n",
+    __FUNCTION__,
+    NewBase,
+    FdtSize
+    ));
+  *FdtHobData = (UINTN)NewBase;
+}
+
 VOID
 MiscInitialization (
   VOID
@@ -368,6 +412,7 @@ MiscInitialization (
       break;
     case 0xffff: /* microvm */
       DEBUG ((DEBUG_INFO, "%a: microvm\n", __FUNCTION__));
+      MicrovmInitialization ();
       PcdStatus = PcdSet16S (
                     PcdOvmfHostBridgePciDevId,
                     MICROVM_PSEUDO_DEVICE_ID
-- 
2.33.1

[PATCH v3 3/5] OvmfPkg/Microvm/fdt: add empty fdt

[Gerd Hoffmann]

FdtClient is unhappy without a device tree, so add an empty fdt
which we can use in case etc/fdt is not present in fw_cfg.

On ARM machines a device tree is mandatory for hardware detection,
thats why FdtClient fails hard.

On microvm the device tree is only used to detect virtio-mmio devices
(this patch series) and the pcie host (future series).  So edk2 can
continue with limited functionality in case no device tree is present:
no storage, no network, but serial console and direct kernel boot
works.

qemu release 6.2 & newer will provide a device tree for microvm.

https://bugzilla.tianocore.org/show_bug.cgi?id=3689
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>
---
 OvmfPkg/PlatformPei/Platform.c | 26 ++++++++++++++++++++++----
 1 file changed, 22 insertions(+), 4 deletions(-)

diff --git a/OvmfPkg/PlatformPei/Platform.c b/OvmfPkg/PlatformPei/Platform.c
index c9ec1d7e99fb..d0323c645162 100644
--- a/OvmfPkg/PlatformPei/Platform.c
+++ b/OvmfPkg/PlatformPei/Platform.c
@@ -16,6 +16,7 @@
 //
 // The Library classes this module consumes
 //
+#include <Library/BaseMemoryLib.h>
 #include <Library/BaseLib.h>
 #include <Library/DebugLib.h>
 #include <Library/HobLib.h>
@@ -321,6 +322,18 @@ PciExBarInitialization (
     );
 }
 
+static const UINT8  EmptyFdt[] = {
+  0xd0, 0x0d, 0xfe, 0xed, 0x00, 0x00, 0x00, 0x48,
+  0x00, 0x00, 0x00, 0x38, 0x00, 0x00, 0x00, 0x48,
+  0x00, 0x00, 0x00, 0x28, 0x00, 0x00, 0x00, 0x11,
+  0x00, 0x00, 0x00, 0x10, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0x09,
+};
+
 VOID
 MicrovmInitialization (
   VOID
@@ -335,8 +348,9 @@ MicrovmInitialization (
 
   Status = QemuFwCfgFindFile ("etc/fdt", &FdtItem, &FdtSize);
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_INFO, "%a: no etc/fdt found in fw_cfg\n", __FUNCTION__));
-    return;
+    DEBUG ((DEBUG_INFO, "%a: no etc/fdt found in fw_cfg, using dummy\n", __FUNCTION__));
+    FdtItem = 0;
+    FdtSize = sizeof (EmptyFdt);
   }
 
   FdtPages = EFI_SIZE_TO_PAGES (FdtSize);
@@ -346,8 +360,12 @@ MicrovmInitialization (
     return;
   }
 
-  QemuFwCfgSelectItem (FdtItem);
-  QemuFwCfgReadBytes (FdtSize, NewBase);
+  if (FdtItem) {
+    QemuFwCfgSelectItem (FdtItem);
+    QemuFwCfgReadBytes (FdtSize, NewBase);
+  } else {
+    CopyMem (NewBase, EmptyFdt, FdtSize);
+  }
 
   FdtHobData = BuildGuidHob (&gFdtHobGuid, sizeof (*FdtHobData));
   if (FdtHobData == NULL) {
-- 
2.33.1

[PATCH v3 4/5] OvmfPkg/Microvm/virtio: add virtio-mmio support

[Gerd Hoffmann]

Add virtio-mmio support (VirtioMmioDeviceLib and VirtioFdtDxe).

With this patch added and a new enough qemu version (6.2+) edk2
will detect virtio-mmio devices, so it is possible to boot from
storage (virtio-blk, virtio-scsi) or network (virtio-net).

https://bugzilla.tianocore.org/show_bug.cgi?id=3689
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 OvmfPkg/Microvm/MicrovmX64.dsc | 2 ++
 OvmfPkg/Microvm/MicrovmX64.fdf | 1 +
 2 files changed, 3 insertions(+)

diff --git a/OvmfPkg/Microvm/MicrovmX64.dsc b/OvmfPkg/Microvm/MicrovmX64.dsc
index edddf6c29b32..a78c8f3dd89f 100644
--- a/OvmfPkg/Microvm/MicrovmX64.dsc
+++ b/OvmfPkg/Microvm/MicrovmX64.dsc
@@ -233,6 +233,7 @@ [LibraryClasses.common]
   SerialPortLib|MdeModulePkg/Library/BaseSerialPortLib16550/BaseSerialPortLib16550.inf
   PlatformHookLib|MdeModulePkg/Library/BasePlatformHookLibNull/BasePlatformHookLibNull.inf
   FdtLib|EmbeddedPkg/Library/FdtLib/FdtLib.inf
+  VirtioMmioDeviceLib|OvmfPkg/Library/VirtioMmioDeviceLib/VirtioMmioDeviceLib.inf
 
 [LibraryClasses.common.SEC]
   QemuFwCfgLib|OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgSecLib.inf
@@ -744,6 +745,7 @@ [Components]
   # device tree
   #
   EmbeddedPkg/Drivers/FdtClientDxe/FdtClientDxe.inf
+  OvmfPkg/Fdt/VirtioFdtDxe/VirtioFdtDxe.inf
 
   #
   # SMBIOS Support
diff --git a/OvmfPkg/Microvm/MicrovmX64.fdf b/OvmfPkg/Microvm/MicrovmX64.fdf
index 905d23b843d3..6999ac1a87b9 100644
--- a/OvmfPkg/Microvm/MicrovmX64.fdf
+++ b/OvmfPkg/Microvm/MicrovmX64.fdf
@@ -277,6 +277,7 @@ [FV.DXEFV]
 INF  OvmfPkg/VirtioFsDxe/VirtioFsDxe.inf
 
 INF  EmbeddedPkg/Drivers/FdtClientDxe/FdtClientDxe.inf
+INF  OvmfPkg/Fdt/VirtioFdtDxe/VirtioFdtDxe.inf
 
 !if $(TOOL_CHAIN_TAG) != "XCODE5"
 INF  ShellPkg/DynamicCommand/TftpDynamicCommand/TftpDynamicCommand.inf
-- 
2.33.1

[PATCH v3 5/5] OvmfPkg/Microvm: add README

[Gerd Hoffmann]

Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3599
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Jiewen Yao <Jiewen.yao@intel.com>
---
 OvmfPkg/Microvm/README | 50 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 50 insertions(+)
 create mode 100644 OvmfPkg/Microvm/README

diff --git a/OvmfPkg/Microvm/README b/OvmfPkg/Microvm/README
new file mode 100644
index 000000000000..540d39f2ec21
--- /dev/null
+++ b/OvmfPkg/Microvm/README
@@ -0,0 +1,50 @@
+
+This is an *experimental* port of OVMF for the QEMU microvm
+machine type.
+
+microvm background info
+-----------------------
+
+microvm is designed for modern, virtio-based workloads.  Most legacy
+lpc/isa devices like pit and pic can be turned off.  virtio-mmio
+(i.e. '-device virtio-{blk,net,scsi,...}-device') is used for
+storage/network/etc.
+
+Optional pcie support is available and any pcie device supported by
+QEMU can be plugged in (including virtio-pci if you prefer that over
+virtio-mmio).
+
+https://qemu.readthedocs.io/en/latest/system/i386/microvm.html
+https://www.kraxel.org/blog/2020/10/qemu-microvm-acpi/
+
+design issues
+-------------
+
+Not fully clear yet how to do hardware detection best.  Right now
+using device tree to find virtio-mmio devices and pcie host bridge,
+can reuse existing ArmVirtPkg code that way.  Needs patched QEMU.
+
+features
+--------
+ [working] serial console
+ [working] direct kernel boot
+ [working] virtio-mmio support
+ [in progress] pcie support
+
+known limitations
+-----------------
+ * rtc=on is required for now.
+ * can't use separate code/vars (actually an microvm limitation,
+   there is no pflash support).
+ * transitional virtio-pci devices do not work.  microvm doesn't
+   support ioports on pcie, and ovmf doesn't initialize pcie devices
+   with ioports if there is no address space for them (even though
+   pcie devices are required to be functional without ioports).
+
+usage
+-----
+qemu-system-x86_64 \
+    -nographic \
+    -machine microvm,acpi=on,pit=off,pic=off,rtc=on \
+    -bios /path/to/MICROVM.fd \
+    [ ... more args here ... ]
-- 
2.33.1

Re: [PATCH v3 2/5] OvmfPkg/Microvm/fdt: load fdt from fw_cfg

[Philippe Mathieu-Daudé]

On 12/13/21 09:16, Gerd Hoffmann wrote:
> Needed for hardware detection: virtio-mmio devices for now,
> later also pcie root bridge.
> 
> Depends on patched qemu which actually provides an fdt:
> https://gitlab.com/kraxel/qemu/-/commits/sirius/microvm-device-tree

Link returns 404.

> 
> https://bugzilla.tianocore.org/show_bug.cgi?id=3689
> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
> ---
>  OvmfPkg/PlatformPei/PlatformPei.inf |  1 +
>  OvmfPkg/PlatformPei/Platform.c      | 45 +++++++++++++++++++++++++++++
>  2 files changed, 46 insertions(+)
> 
> diff --git a/OvmfPkg/PlatformPei/PlatformPei.inf b/OvmfPkg/PlatformPei/PlatformPei.inf
> index 1c56ba275835..8ef404168c45 100644
> --- a/OvmfPkg/PlatformPei/PlatformPei.inf
> +++ b/OvmfPkg/PlatformPei/PlatformPei.inf
> @@ -44,6 +44,7 @@ [Packages]
>  
>  [Guids]
>    gEfiMemoryTypeInformationGuid
> +  gFdtHobGuid
>  
>  [LibraryClasses]
>    BaseLib
> diff --git a/OvmfPkg/PlatformPei/Platform.c b/OvmfPkg/PlatformPei/Platform.c
> index 906f64615de7..c9ec1d7e99fb 100644
> --- a/OvmfPkg/PlatformPei/Platform.c
> +++ b/OvmfPkg/PlatformPei/Platform.c
> @@ -321,6 +321,50 @@ PciExBarInitialization (
>      );
>  }
>  
> +VOID
> +MicrovmInitialization (
> +  VOID
> +  )
> +{
> +  FIRMWARE_CONFIG_ITEM  FdtItem;
> +  UINTN                 FdtSize;
> +  UINTN                 FdtPages;
> +  EFI_STATUS            Status;
> +  UINT64                *FdtHobData;
> +  VOID                  *NewBase;
> +
> +  Status = QemuFwCfgFindFile ("etc/fdt", &FdtItem, &FdtSize);
> +  if (EFI_ERROR (Status)) {
> +    DEBUG ((DEBUG_INFO, "%a: no etc/fdt found in fw_cfg\n", __FUNCTION__));
> +    return;
> +  }
> +
> +  FdtPages = EFI_SIZE_TO_PAGES (FdtSize);
> +  NewBase  = AllocatePages (FdtPages);
> +  if (NewBase == NULL) {
> +    DEBUG ((DEBUG_INFO, "%a: AllocatePages failed\n", __FUNCTION__));
> +    return;
> +  }
> +
> +  QemuFwCfgSelectItem (FdtItem);
> +  QemuFwCfgReadBytes (FdtSize, NewBase);
> +
> +  FdtHobData = BuildGuidHob (&gFdtHobGuid, sizeof (*FdtHobData));
> +  if (FdtHobData == NULL) {
> +    DEBUG ((DEBUG_INFO, "%a: BuildGuidHob failed\n", __FUNCTION__));

       FreePages (NewBase)?

Otherwise:
Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>

> +    return;
> +  }
> +
> +  DEBUG ((
> +    DEBUG_INFO,
> +    "%a: fdt at 0x%x (size %d)\n",
> +    __FUNCTION__,
> +    NewBase,
> +    FdtSize
> +    ));
> +  *FdtHobData = (UINTN)NewBase;
> +}
> +
>  VOID
>  MiscInitialization (
>    VOID
> @@ -368,6 +412,7 @@ MiscInitialization (
>        break;
>      case 0xffff: /* microvm */
>        DEBUG ((DEBUG_INFO, "%a: microvm\n", __FUNCTION__));
> +      MicrovmInitialization ();
>        PcdStatus = PcdSet16S (
>                      PcdOvmfHostBridgePciDevId,
>                      MICROVM_PSEUDO_DEVICE_ID
> 

Re: [PATCH v3 3/5] OvmfPkg/Microvm/fdt: add empty fdt

[Philippe Mathieu-Daudé]

On 12/13/21 09:16, Gerd Hoffmann wrote:
> FdtClient is unhappy without a device tree, so add an empty fdt
> which we can use in case etc/fdt is not present in fw_cfg.
> 
> On ARM machines a device tree is mandatory for hardware detection,
> thats why FdtClient fails hard.

"that's"

> 
> On microvm the device tree is only used to detect virtio-mmio devices
> (this patch series) and the pcie host (future series).  So edk2 can
> continue with limited functionality in case no device tree is present:
> no storage, no network, but serial console and direct kernel boot
> works.
> 
> qemu release 6.2 & newer will provide a device tree for microvm.
> 
> https://bugzilla.tianocore.org/show_bug.cgi?id=3689
> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
> Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>
> ---
>  OvmfPkg/PlatformPei/Platform.c | 26 ++++++++++++++++++++++----
>  1 file changed, 22 insertions(+), 4 deletions(-)

Re: [PATCH v3 5/5] OvmfPkg/Microvm: add README

[Philippe Mathieu-Daudé]

On 12/13/21 09:16, Gerd Hoffmann wrote:
> Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3599
> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
> Acked-by: Jiewen Yao <Jiewen.yao@intel.com>
> ---
>  OvmfPkg/Microvm/README | 50 ++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 50 insertions(+)
>  create mode 100644 OvmfPkg/Microvm/README

Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>

Re: [PATCH v3 4/5] OvmfPkg/Microvm/virtio: add virtio-mmio support

[Philippe Mathieu-Daudé]

On 12/13/21 09:16, Gerd Hoffmann wrote:
> Add virtio-mmio support (VirtioMmioDeviceLib and VirtioFdtDxe).
> 
> With this patch added and a new enough qemu version (6.2+) edk2
> will detect virtio-mmio devices, so it is possible to boot from
> storage (virtio-blk, virtio-scsi) or network (virtio-net).
> 
> https://bugzilla.tianocore.org/show_bug.cgi?id=3689
> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
> ---
>  OvmfPkg/Microvm/MicrovmX64.dsc | 2 ++
>  OvmfPkg/Microvm/MicrovmX64.fdf | 1 +
>  2 files changed, 3 insertions(+)

Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>

Re: [PATCH v3 1/5] OvmfPkg/Microvm/fdt: add device tree support

[Philippe Mathieu-Daudé]

On 12/13/21 09:16, Gerd Hoffmann wrote:
> Add fdt parser from EmbeddedPkg (FdtLib and FdtClientDxe) to MicrovmX64.
> 
> Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3689
> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
> ---
>  OvmfPkg/Microvm/MicrovmX64.dsc | 6 ++++++
>  OvmfPkg/Microvm/MicrovmX64.fdf | 2 ++
>  2 files changed, 8 insertions(+)

Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>

Re: [edk2-devel] [PATCH v3 2/5] OvmfPkg/Microvm/fdt: load fdt from fw_cfg

[Ard Biesheuvel]

On Mon, 13 Dec 2021 at 09:17, Gerd Hoffmann <kraxel@redhat.com> wrote:
>
> Needed for hardware detection: virtio-mmio devices for now,
> later also pcie root bridge.
>
> Depends on patched qemu which actually provides an fdt:
> https://gitlab.com/kraxel/qemu/-/commits/sirius/microvm-device-tree
>
> https://bugzilla.tianocore.org/show_bug.cgi?id=3689
> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
> ---
>  OvmfPkg/PlatformPei/PlatformPei.inf |  1 +
>  OvmfPkg/PlatformPei/Platform.c      | 45 +++++++++++++++++++++++++++++
>  2 files changed, 46 insertions(+)
>
> diff --git a/OvmfPkg/PlatformPei/PlatformPei.inf b/OvmfPkg/PlatformPei/PlatformPei.inf
> index 1c56ba275835..8ef404168c45 100644
> --- a/OvmfPkg/PlatformPei/PlatformPei.inf
> +++ b/OvmfPkg/PlatformPei/PlatformPei.inf
> @@ -44,6 +44,7 @@ [Packages]
>
>  [Guids]
>    gEfiMemoryTypeInformationGuid
> +  gFdtHobGuid
>
>  [LibraryClasses]
>    BaseLib
> diff --git a/OvmfPkg/PlatformPei/Platform.c b/OvmfPkg/PlatformPei/Platform.c
> index 906f64615de7..c9ec1d7e99fb 100644
> --- a/OvmfPkg/PlatformPei/Platform.c
> +++ b/OvmfPkg/PlatformPei/Platform.c
> @@ -321,6 +321,50 @@ PciExBarInitialization (
>      );
>  }
>
> +VOID
> +MicrovmInitialization (
> +  VOID
> +  )
> +{
> +  FIRMWARE_CONFIG_ITEM  FdtItem;
> +  UINTN                 FdtSize;
> +  UINTN                 FdtPages;
> +  EFI_STATUS            Status;
> +  UINT64                *FdtHobData;
> +  VOID                  *NewBase;
> +
> +  Status = QemuFwCfgFindFile ("etc/fdt", &FdtItem, &FdtSize);
> +  if (EFI_ERROR (Status)) {
> +    DEBUG ((DEBUG_INFO, "%a: no etc/fdt found in fw_cfg\n", __FUNCTION__));
> +    return;
> +  }
> +
> +  FdtPages = EFI_SIZE_TO_PAGES (FdtSize);
> +  NewBase  = AllocatePages (FdtPages);
> +  if (NewBase == NULL) {
> +    DEBUG ((DEBUG_INFO, "%a: AllocatePages failed\n", __FUNCTION__));
> +    return;
> +  }
> +
> +  QemuFwCfgSelectItem (FdtItem);
> +  QemuFwCfgReadBytes (FdtSize, NewBase);
> +
> +  FdtHobData = BuildGuidHob (&gFdtHobGuid, sizeof (*FdtHobData));
> +  if (FdtHobData == NULL) {
> +    DEBUG ((DEBUG_INFO, "%a: BuildGuidHob failed\n", __FUNCTION__));
> +    return;
> +  }
> +
> +  DEBUG ((
> +    DEBUG_INFO,
> +    "%a: fdt at 0x%x (size %d)\n",
> +    __FUNCTION__,
> +    NewBase,
> +    FdtSize
> +    ));
> +  *FdtHobData = (UINTN)NewBase;
> +}
> +
>  VOID
>  MiscInitialization (
>    VOID
> @@ -368,6 +412,7 @@ MiscInitialization (
>        break;
>      case 0xffff: /* microvm */
>        DEBUG ((DEBUG_INFO, "%a: microvm\n", __FUNCTION__));
> +      MicrovmInitialization ();

Is this the best spot for calling Microvm related init code that is
entirely unrelated to PCIe?

>        PcdStatus = PcdSet16S (
>                      PcdOvmfHostBridgePciDevId,
>                      MICROVM_PSEUDO_DEVICE_ID
> --
> 2.33.1
>
>
>
> 
>
>

Re: [PATCH v3 2/5] OvmfPkg/Microvm/fdt: load fdt from fw_cfg

[Gerd Hoffmann]

On Mon, Dec 13, 2021 at 10:33:55AM +0100, Philippe Mathieu-Daudé wrote:
> On 12/13/21 09:16, Gerd Hoffmann wrote:
> > Needed for hardware detection: virtio-mmio devices for now,
> > later also pcie root bridge.
> > 
> > Depends on patched qemu which actually provides an fdt:
> > https://gitlab.com/kraxel/qemu/-/commits/sirius/microvm-device-tree
> 
> Link returns 404.

Oh, need to fix the commit message.  It's upstream in qemu 6.2+
meanwhile.

take care,
  Gerd

Re: [edk2-devel] [PATCH v3 2/5] OvmfPkg/Microvm/fdt: load fdt from fw_cfg

[Gerd Hoffmann]

  Hi,

> > @@ -368,6 +412,7 @@ MiscInitialization (
> >        break;
> >      case 0xffff: /* microvm */
> >        DEBUG ((DEBUG_INFO, "%a: microvm\n", __FUNCTION__));
> > +      MicrovmInitialization ();
> 
> Is this the best spot for calling Microvm related init code that is
> entirely unrelated to PCIe?

Looked like the best place to me.  Various platform-specific
initialization happens there.  And, yes, for 'pc' and 'q35'
qemu machines this includes pci host bridge setup.

Do you have a better suggestion?

take care,
  Gerd

Re: [edk2-devel] [PATCH v3 2/5] OvmfPkg/Microvm/fdt: load fdt from fw_cfg

[Ard Biesheuvel]

On Mon, 13 Dec 2021 at 12:26, Gerd Hoffmann <kraxel@redhat.com> wrote:
>
>   Hi,
>
> > > @@ -368,6 +412,7 @@ MiscInitialization (
> > >        break;
> > >      case 0xffff: /* microvm */
> > >        DEBUG ((DEBUG_INFO, "%a: microvm\n", __FUNCTION__));
> > > +      MicrovmInitialization ();
> >
> > Is this the best spot for calling Microvm related init code that is
> > entirely unrelated to PCIe?
>
> Looked like the best place to me.  Various platform-specific
> initialization happens there.  And, yes, for 'pc' and 'q35'
> qemu machines this includes pci host bridge setup.
>

Fair enough. Given the comment that future changes will include DT
based PCIe host bridge probing, I think this is fine.

Re: [PATCH v3 0/5] OvmfPkg/Microvm: second batch of microvm patches

[Ard Biesheuvel]

On Mon, 13 Dec 2021 at 09:17, Gerd Hoffmann <kraxel@redhat.com> wrote:
>
> Adds support for virtio-mmio devices to microvm.
>
> While being at it also add the README, the
> patch somehow disappeared from the first batch.
>
> v3:
>  - uncrustify & rebase to latest master
>  - pick up some review tags
>  - minor README updates.
>
> v2:
>  - qemu changes needed for this are merged and will be
>    in the 6.2 release (dec 2021).
>  - more verbose commit messages.
>
> Gerd Hoffmann (5):
>   OvmfPkg/Microvm/fdt: add device tree support
>   OvmfPkg/Microvm/fdt: load fdt from fw_cfg
>   OvmfPkg/Microvm/fdt: add empty fdt
>   OvmfPkg/Microvm/virtio: add virtio-mmio support
>   OvmfPkg/Microvm: add README
>

Merged as #2295

Thanks,

>  OvmfPkg/Microvm/MicrovmX64.dsc      |  8 ++++
>  OvmfPkg/Microvm/MicrovmX64.fdf      |  3 ++
>  OvmfPkg/PlatformPei/PlatformPei.inf |  1 +
>  OvmfPkg/PlatformPei/Platform.c      | 63 +++++++++++++++++++++++++++++
>  OvmfPkg/Microvm/README              | 50 +++++++++++++++++++++++
>  5 files changed, 125 insertions(+)
>  create mode 100644 OvmfPkg/Microvm/README
>
> --
> 2.33.1
>