EmbeddedPkg: add driver to set graphical/serial console preference

Linux on ARM/arm64 will infer from the presence of a /chosen/stdout-path
DT property or of a SPCR ACPI table that the primary console is the serial
port, even if a graphical console is available as well.

So let's introduce a driver that allows the user to set a preference
between graphical and serial if both are available. If the preference
is set to 'Graphical', and any GOP protocol instances have been installed
by the time the ReadyToBoot event is signalled, remove the DT property
and/or the SPCR table entirely.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>

1 files changed, 293 insertions, 0 deletions

diff --git a/EmbeddedPkg/Drivers/ConsolePrefDxe/ConsolePrefDxe.c b/EmbeddedPkg/Drivers/ConsolePrefDxe/ConsolePrefDxe.c
new file mode 100644
index 0000000000..996d1a6036
--- /dev/null
+++ b/EmbeddedPkg/Drivers/ConsolePrefDxe/ConsolePrefDxe.c
@@ -0,0 +1,293 @@
+/** @file

+*

+*  Copyright (c) 2017, Linaro, Ltd. 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 <IndustryStandard/Acpi.h>

+#include <libfdt.h>

+#include <Library/BaseLib.h>

+#include <Library/DebugLib.h>

+#include <Library/DevicePathLib.h>

+#include <Library/HiiLib.h>

+#include <Library/UefiBootServicesTableLib.h>

+#include <Library/UefiBootServicesTableLib.h>

+#include <Library/UefiDriverEntryPoint.h>

+#include <Library/UefiLib.h>

+#include <Library/UefiRuntimeServicesTableLib.h>

+

+#include <Protocol/AcpiTable.h>

+#include <Protocol/AcpiSystemDescriptionTable.h>

+

+#include "ConsolePrefDxe.h"

+

+#define SPCR_SIG    EFI_ACPI_2_0_SERIAL_PORT_CONSOLE_REDIRECTION_TABLE_SIGNATURE

+

+extern  UINT8                     ConsolePrefHiiBin[];

+extern  UINT8                     ConsolePrefDxeStrings[];

+

+typedef struct {

+  VENDOR_DEVICE_PATH              VendorDevicePath;

+  EFI_DEVICE_PATH_PROTOCOL        End;

+} HII_VENDOR_DEVICE_PATH;

+

+STATIC HII_VENDOR_DEVICE_PATH     mConsolePrefDxeVendorDevicePath = {

+  {

+    {

+      HARDWARE_DEVICE_PATH,

+      HW_VENDOR_DP,

+      {

+        (UINT8) (sizeof (VENDOR_DEVICE_PATH)),

+        (UINT8) ((sizeof (VENDOR_DEVICE_PATH)) >> 8)

+      }

+    },

+    CONSOLE_PREF_FORMSET_GUID

+  },

+  {

+    END_DEVICE_PATH_TYPE,

+    END_ENTIRE_DEVICE_PATH_SUBTYPE,

+    {

+      (UINT8) (END_DEVICE_PATH_LENGTH),

+      (UINT8) ((END_DEVICE_PATH_LENGTH) >> 8)

+    }

+  }

+};

+

+STATIC EFI_EVENT                  mReadyToBootEvent;

+

+STATIC

+EFI_STATUS

+InstallHiiPages (

+  VOID

+  )

+{

+  EFI_STATUS                      Status;

+  EFI_HII_HANDLE                  HiiHandle;

+  EFI_HANDLE                      DriverHandle;

+

+  DriverHandle = NULL;

+  Status = gBS->InstallMultipleProtocolInterfaces (&DriverHandle,

+                  &gEfiDevicePathProtocolGuid,

+                  &mConsolePrefDxeVendorDevicePath,

+                  NULL);

+  if (EFI_ERROR (Status)) {

+    return Status;

+  }

+

+  HiiHandle = HiiAddPackages (&gConsolePrefFormSetGuid,

+                              DriverHandle,

+                              ConsolePrefDxeStrings,

+                              ConsolePrefHiiBin,

+                              NULL);

+

+  if (HiiHandle == NULL) {

+    gBS->UninstallMultipleProtocolInterfaces (DriverHandle,

+           &gEfiDevicePathProtocolGuid,

+           &mConsolePrefDxeVendorDevicePath,

+           NULL);

+    return EFI_OUT_OF_RESOURCES;

+  }

+  return EFI_SUCCESS;

+}

+

+STATIC

+VOID

+RemoveDtStdoutPath (

+  VOID

+)

+{

+  VOID        *Dtb;

+  INT32       Node;

+  INT32       Error;

+  EFI_STATUS  Status;

+

+  Status = EfiGetSystemConfigurationTable (&gFdtTableGuid, &Dtb);

+  if (EFI_ERROR (Status)) {

+    DEBUG ((DEBUG_INFO, "%a: could not retrieve DT blob - %r\n", __FUNCTION__,

+      Status));

+    return;

+  }

+

+  Node = fdt_path_offset (Dtb, "/chosen");

+  if (Node < 0) {

+    return;

+  }

+

+  Error = fdt_delprop (Dtb, Node, "stdout-path");

+  if (Error) {

+    DEBUG ((DEBUG_INFO, "%a: Failed to delete 'stdout-path' property: %a\n",

+      __FUNCTION__, fdt_strerror (Error)));

+  }

+}

+

+STATIC

+VOID

+RemoveSpcrTable (

+  VOID

+  )

+{

+  EFI_ACPI_SDT_PROTOCOL           *Sdt;

+  EFI_ACPI_TABLE_PROTOCOL         *AcpiTable;

+  EFI_STATUS                      Status;

+  UINTN                           TableIndex;

+  EFI_ACPI_SDT_HEADER             *TableHeader;

+  EFI_ACPI_TABLE_VERSION          TableVersion;

+  UINTN                           TableKey;

+

+  Status = gBS->LocateProtocol (&gEfiAcpiTableProtocolGuid, NULL,

+                  (VOID **)&AcpiTable);

+  if (EFI_ERROR (Status)) {

+    return;

+  }

+

+  Status = gBS->LocateProtocol (&gEfiAcpiSdtProtocolGuid, NULL, (VOID **)&Sdt);

+  if (EFI_ERROR (Status)) {

+    return;

+  }

+

+  TableIndex  = 0;

+  TableKey    = 0;

+  TableHeader = NULL;

+

+  do {

+    Status = Sdt->GetAcpiTable (TableIndex++, &TableHeader, &TableVersion,

+                    &TableKey);

+    if (EFI_ERROR (Status)) {

+      break;

+    }

+

+    if (TableHeader->Signature != SPCR_SIG) {

+      continue;

+    }

+

+    Status = AcpiTable->UninstallAcpiTable (AcpiTable, TableKey);

+    if (EFI_ERROR (Status)) {

+      DEBUG ((DEBUG_WARN, "%a: failed to uninstall SPCR table - %r\n",

+        __FUNCTION__, Status));

+    }

+    break;

+  } while (TRUE);

+}

+

+STATIC

+VOID

+OnReadyToBoot (

+  IN EFI_EVENT  Event,

+  IN VOID       *Context

+  )

+{

+  CONSOLE_PREF_VARSTORE_DATA      ConsolePref;

+  UINTN                           BufferSize;

+  EFI_STATUS                      Status;

+  VOID                            *Gop;

+

+  BufferSize = sizeof (ConsolePref);

+  Status = gRT->GetVariable (CONSOLE_PREF_VARIABLE_NAME,

+                  &gConsolePrefFormSetGuid, NULL, &BufferSize, &ConsolePref);

+  if (EFI_ERROR (Status)) {

+    DEBUG ((DEBUG_ERROR,

+      "%a: variable '%s' could not be read - bailing!\n", __FUNCTION__,

+      CONSOLE_PREF_VARIABLE_NAME));

+    return;

+  }

+

+  if (ConsolePref.Console == CONSOLE_PREF_SERIAL) {

+    DEBUG ((DEBUG_INFO,

+      "%a: serial console preferred - doing nothing\n", __FUNCTION__));

+    return;

+  }

+

+  //

+  // Check if any GOP instances exist: if so, disable stdout-path and SPCR

+  //

+  Status = gBS->LocateProtocol (&gEfiGraphicsOutputProtocolGuid, NULL, &Gop);

+  if (EFI_ERROR (Status)) {

+    DEBUG ((DEBUG_INFO,

+      "%a: no GOP instances found - doing nothing (%r)\n", __FUNCTION__,

+      Status));

+    return;

+  }

+

+  RemoveDtStdoutPath ();

+  RemoveSpcrTable ();

+}

+

+/**

+  The entry point for ConsolePrefDxe driver.

+

+  @param[in] ImageHandle     The image handle of the driver.

+  @param[in] SystemTable     The system table.

+

+  @retval EFI_ALREADY_STARTED     The driver already exists in system.

+  @retval EFI_OUT_OF_RESOURCES    Fail to execute entry point due to lack of

+                                  resources.

+  @retval EFI_SUCCES              All the related protocols are installed on

+                                  the driver.

+

+**/

+EFI_STATUS

+EFIAPI

+ConsolePrefDxeEntryPoint (

+  IN EFI_HANDLE                   ImageHandle,

+  IN EFI_SYSTEM_TABLE             *SystemTable

+  )

+{

+  EFI_STATUS                      Status;

+  CONSOLE_PREF_VARSTORE_DATA      ConsolePref;

+  UINTN                           BufferSize;

+

+  //

+  // Get the current console preference from the ConsolePref variable.

+  //

+  BufferSize = sizeof (ConsolePref);

+  Status = gRT->GetVariable (CONSOLE_PREF_VARIABLE_NAME,

+                  &gConsolePrefFormSetGuid, NULL, &BufferSize, &ConsolePref);

+  if (EFI_ERROR (Status)) {

+    DEBUG ((DEBUG_INFO,

+      "%a: no console preference found, defaulting to graphical\n",

+      __FUNCTION__));

+    ConsolePref.Console = CONSOLE_PREF_GRAPHICAL;

+  }

+

+  if (!EFI_ERROR (Status) &&

+      ConsolePref.Console != CONSOLE_PREF_GRAPHICAL &&

+      ConsolePref.Console != CONSOLE_PREF_SERIAL) {

+    DEBUG ((DEBUG_WARN, "%a: invalid value for %s, defaulting to graphical\n",

+      __FUNCTION__, CONSOLE_PREF_VARIABLE_NAME));

+    ConsolePref.Console = CONSOLE_PREF_GRAPHICAL;

+    Status = EFI_INVALID_PARAMETER; // trigger setvar below

+  }

+

+  //

+  // Write the newly selected value back to the variable store.

+  //

+  if (EFI_ERROR (Status)) {

+    ZeroMem (&ConsolePref.Reserved, sizeof (ConsolePref.Reserved));

+    Status = gRT->SetVariable (CONSOLE_PREF_VARIABLE_NAME,

+                    &gConsolePrefFormSetGuid,

+                    EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS,

+                    sizeof (ConsolePref), &ConsolePref);

+

+    if (EFI_ERROR (Status)) {

+      DEBUG ((DEBUG_ERROR, "%a: gRT->SetVariable () failed - %r\n",

+        __FUNCTION__, Status));

+      return Status;

+    }

+  }

+

+  Status = gBS->CreateEventEx (EVT_NOTIFY_SIGNAL, TPL_CALLBACK,

+                  OnReadyToBoot, NULL, &gEfiEventReadyToBootGuid,

+                  &mReadyToBootEvent);

+  ASSERT_EFI_ERROR (Status);

+

+  return InstallHiiPages ();

+}