The CountCpusFromFdt function is now used in two places. Create FdtHelperLib for this and similar functions.
Signed-off-by: Rebecca Cran <rebe...@nuviainc.com> Reviewed-by: Leif Lindholm <l...@nuviainc.com> --- Platform/Qemu/SbsaQemu/SbsaQemu.dsc | 2 + Silicon/Qemu/SbsaQemu/Include/Library/FdtHelperLib.h | 24 ++++++++ Silicon/Qemu/SbsaQemu/Library/FdtHelperLib/FdtHelperLib.c | 62 ++++++++++++++++++++ Silicon/Qemu/SbsaQemu/Library/FdtHelperLib/FdtHelperLib.inf | 28 +++++++++ 4 files changed, 116 insertions(+) diff --git a/Platform/Qemu/SbsaQemu/SbsaQemu.dsc b/Platform/Qemu/SbsaQemu/SbsaQemu.dsc index f6af3f9111ee..8faad3eda217 100644 --- a/Platform/Qemu/SbsaQemu/SbsaQemu.dsc +++ b/Platform/Qemu/SbsaQemu/SbsaQemu.dsc @@ -121,6 +121,8 @@ DEFINE NETWORK_HTTP_BOOT_ENABLE = FALSE # ARM PL011 UART Driver PL011UartLib|ArmPlatformPkg/Library/PL011UartLib/PL011UartLib.inf + FdtHelperLib|Silicon/Qemu/SbsaQemu/Library/FdtHelperLib/FdtHelperLib.inf + # Debug Support PeCoffExtraActionLib|ArmPkg/Library/DebugPeCoffExtraActionLib/DebugPeCoffExtraActionLib.inf DebugAgentLib|MdeModulePkg/Library/DebugAgentLibNull/DebugAgentLibNull.inf diff --git a/Silicon/Qemu/SbsaQemu/Include/Library/FdtHelperLib.h b/Silicon/Qemu/SbsaQemu/Include/Library/FdtHelperLib.h new file mode 100644 index 000000000000..e9e7281c1342 --- /dev/null +++ b/Silicon/Qemu/SbsaQemu/Include/Library/FdtHelperLib.h @@ -0,0 +1,24 @@ +/** @file +* FdtHelperLib.h +* +* Copyright (c) 2021, NUVIA Inc. All rights reserved. +* +* SPDX-License-Identifier: BSD-2-Clause-Patent +* +**/ + +#ifndef FDT_HELPER_LIB_ +#define FDT_HELPER_LIB_ + +/** Walks through the Device Tree created by Qemu and counts the number + of CPUs present in it. + + @return The number of CPUs present. +**/ +EFIAPI +UINT32 +FdtHelperCountCpus ( + VOID + ); + +#endif /* FDT_HELPER_LIB_ */ diff --git a/Silicon/Qemu/SbsaQemu/Library/FdtHelperLib/FdtHelperLib.c b/Silicon/Qemu/SbsaQemu/Library/FdtHelperLib/FdtHelperLib.c new file mode 100644 index 000000000000..411f035ee7d8 --- /dev/null +++ b/Silicon/Qemu/SbsaQemu/Library/FdtHelperLib/FdtHelperLib.c @@ -0,0 +1,62 @@ +/** @file +* FdtHelperLib.c +* +* Copyright (c) 2021, NUVIA Inc. All rights reserved. +* Copyright (c) 2020, Linaro Ltd. All rights reserved. +* +* SPDX-License-Identifier: BSD-2-Clause-Patent +* +**/ + +#include <Uefi.h> +#include <Library/DebugLib.h> +#include <Library/FdtHelperLib.h> +#include <Library/PcdLib.h> +#include <libfdt.h> + +/** Walks through the Device Tree created by Qemu and counts the number + of CPUs present in it. + + @return The number of CPUs present. +**/ +EFIAPI +UINT32 +FdtHelperCountCpus ( + VOID + ) +{ + VOID *DeviceTreeBase; + INT32 Node; + INT32 Prev; + INT32 CpuNode; + UINT32 CpuCount; + + DeviceTreeBase = (VOID *)(UINTN)PcdGet64 (PcdDeviceTreeBaseAddress); + ASSERT (DeviceTreeBase != NULL); + + // Make sure we have a valid device tree blob + ASSERT (fdt_check_header (DeviceTreeBase) == 0); + + CpuNode = fdt_path_offset (DeviceTreeBase, "/cpus"); + if (CpuNode <= 0) { + DEBUG ((DEBUG_ERROR, "Unable to locate /cpus in device tree\n")); + return 0; + } + + CpuCount = 0; + + // Walk through /cpus node and count the number of subnodes. + // The count of these subnodes corresponds to the number of + // CPUs created by Qemu. + Prev = fdt_first_subnode (DeviceTreeBase, CpuNode); + while (1) { + CpuCount++; + Node = fdt_next_subnode (DeviceTreeBase, Prev); + if (Node < 0) { + break; + } + Prev = Node; + } + + return CpuCount; +} diff --git a/Silicon/Qemu/SbsaQemu/Library/FdtHelperLib/FdtHelperLib.inf b/Silicon/Qemu/SbsaQemu/Library/FdtHelperLib/FdtHelperLib.inf new file mode 100644 index 000000000000..d84c16f888d1 --- /dev/null +++ b/Silicon/Qemu/SbsaQemu/Library/FdtHelperLib/FdtHelperLib.inf @@ -0,0 +1,28 @@ +#/** @file +# +# Component description file for FdtHelperLib module +# +# Copyright (c) 2021, NUVIA Inc. All rights reserved. +# +# SPDX-License-Identifier: BSD-2-Clause-Patent +# +#**/ + +[Defines] + INF_VERSION = 1.29 + BASE_NAME = FdtHelperLib + FILE_GUID = 34e4396f-c2fc-4f9e-ad58-0f98e99e3875 + MODULE_TYPE = BASE + VERSION_STRING = 1.0 + LIBRARY_CLASS = FdtHelperLib + +[Sources.common] + FdtHelperLib.c + +[Packages] + EmbeddedPkg/EmbeddedPkg.dec + MdePkg/MdePkg.dec + Silicon/Qemu/SbsaQemu/SbsaQemu.dec + +[FixedPcd] + gArmVirtSbsaQemuPlatformTokenSpaceGuid.PcdDeviceTreeBaseAddress -- 2.26.2 -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#72102): https://edk2.groups.io/g/devel/message/72102 Mute This Topic: https://groups.io/mt/80857021/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-