From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7BCBEC43461 for ; Sat, 12 Sep 2020 02:04:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3A0DC221E5 for ; Sat, 12 Sep 2020 02:04:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=atishpatra.org header.i=@atishpatra.org header.b="XibnteCW" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725794AbgILCE2 (ORCPT ); Fri, 11 Sep 2020 22:04:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48088 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725681AbgILCEY (ORCPT ); Fri, 11 Sep 2020 22:04:24 -0400 Received: from mail-wr1-x441.google.com (mail-wr1-x441.google.com [IPv6:2a00:1450:4864:20::441]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DF61CC061757 for ; Fri, 11 Sep 2020 19:04:23 -0700 (PDT) Received: by mail-wr1-x441.google.com with SMTP id m6so13171238wrn.0 for ; Fri, 11 Sep 2020 19:04:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=atishpatra.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=JWzLvfH+EXgz9JW0/NUVDbNn7eW3zrYpiYa7kgva7WE=; b=XibnteCW1uL3Kh3Dh2fxAurv7pSASLr5kY6yPM6Zo7dYMOvhYDEOpTLkY7Jd1878zq HAbDn2WWSMAtvhBKgeslq5wkglqXaDDs7OMfil754CVnV1YqWX5o+3jZ0Evswif+eif2 uu7nFRzlFte66e5yKjYZoVkI772dxTw+FenVE= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=JWzLvfH+EXgz9JW0/NUVDbNn7eW3zrYpiYa7kgva7WE=; b=AtBN5SCgVz0YkLRaCTY1WzPXnboLtRJST1uoQOE2wf5UrA8jvwoGn+cu5/gzYIClfy SydhiK/MoS8alY987ci+INOZRNeKB1pTEzl4aYMjHrLTBgVHWkp6CYk6V986oMY15rs+ vL2BEsOZQKBNKmX5QUVy89fDCHCmeLjrNtZwlZKQOZ9SAxRjmuMAIvxpbznN04uTxtcD QSkN1jomQAnrkpbYOfL9zmj7LY9ViGR8u3f6FHMjpxyGtmPRmktcPiHB9YmpKoeF9gnM n35XM8xGyoADJyWPIXIFbyceMX67G2WBnQyn6RNtSH74X/5WMs8qEt/iPJ7m4PdHj9jF u4xQ== X-Gm-Message-State: AOAM533+fIwjm02S3gjFyj7STgIgM5KRE1sTPB0kaRT01AJRRgyfgwEZ iz0//F/SUR7fbG9OL5DOvqLawIIMSwsXjE3/gLNm X-Google-Smtp-Source: ABdhPJznj/Du/b3QyxqTvoc0swngIj5Vr6zYesCPHebCcyvJS4FMIbzuOsF0/r6r3VNTqw71HMz2WNB5OP5ZdhuSYWo= X-Received: by 2002:adf:9f10:: with SMTP id l16mr4965247wrf.77.1599876262204; Fri, 11 Sep 2020 19:04:22 -0700 (PDT) MIME-Version: 1.0 References: <20200828172036.8056-1-atish.patra@wdc.com> <20200828172036.8056-6-atish.patra@wdc.com> In-Reply-To: From: Atish Patra Date: Fri, 11 Sep 2020 19:04:11 -0700 Message-ID: Subject: Re: [PATCH v7 5/9] RISC-V: Add PE/COFF header for EFI stub To: Ard Biesheuvel Cc: Atish Patra , linux-efi , Anup Patel , Masahiro Yamada , Anup Patel , Nick Desaulniers , Linux Kernel Mailing List , Arvind Sankar , Palmer Dabbelt , Alistair Francis , Paul Walmsley , Greentime Hu , linux-riscv , Ingo Molnar , Mike Rapoport Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Sep 11, 2020 at 6:09 AM Ard Biesheuvel wrote: > > On Fri, 28 Aug 2020 at 20:20, Atish Patra wrote: > > > > Linux kernel Image can appear as an EFI application With appropriate > > PE/COFF header fields in the beginning of the Image header. An EFI > > application loader can directly load a Linux kernel Image and an EFI > > stub residing in kernel can boot Linux kernel directly. > > > > Add the necessary PE/COFF header. > > > > Signed-off-by: Atish Patra > > Link: https://lore.kernel.org/r/20200421033336.9663-3-atish.patra@wdc.com > > [ardb: - use C prefix for c.li to ensure the expected opcode is emitted > > - align all image sections according to PE/COFF section alignment ] > > Signed-off-by: Ard Biesheuvel > > Reviewed-by: Anup Patel > > Since you need to respin this anyway, one comment below on a thing > that I spotted while revisiting these patches. > > > --- > > arch/riscv/include/asm/sections.h | 13 ++++ > > arch/riscv/kernel/Makefile | 4 ++ > > arch/riscv/kernel/efi-header.S | 104 ++++++++++++++++++++++++++++++ > > arch/riscv/kernel/head.S | 16 +++++ > > arch/riscv/kernel/image-vars.h | 51 +++++++++++++++ > > arch/riscv/kernel/vmlinux.lds.S | 22 ++++++- > > 6 files changed, 208 insertions(+), 2 deletions(-) > > create mode 100644 arch/riscv/include/asm/sections.h > > create mode 100644 arch/riscv/kernel/efi-header.S > > create mode 100644 arch/riscv/kernel/image-vars.h > > > > diff --git a/arch/riscv/include/asm/sections.h b/arch/riscv/include/asm/sections.h > > new file mode 100644 > > index 000000000000..3a9971b1210f > > --- /dev/null > > +++ b/arch/riscv/include/asm/sections.h > > @@ -0,0 +1,13 @@ > > +/* SPDX-License-Identifier: GPL-2.0-only */ > > +/* > > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > > + */ > > +#ifndef __ASM_SECTIONS_H > > +#define __ASM_SECTIONS_H > > + > > +#include > > + > > +extern char _start[]; > > +extern char _start_kernel[]; > > + > > +#endif /* __ASM_SECTIONS_H */ > > diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile > > index dc93710f0b2f..41e3895a3192 100644 > > --- a/arch/riscv/kernel/Makefile > > +++ b/arch/riscv/kernel/Makefile > > @@ -31,6 +31,10 @@ obj-y += cacheinfo.o > > obj-y += patch.o > > obj-$(CONFIG_MMU) += vdso.o vdso/ > > > > +OBJCOPYFLAGS := --prefix-symbols=__efistub_ > > +$(obj)/%.stub.o: $(obj)/%.o FORCE > > + $(call if_changed,objcopy) > > + > > obj-$(CONFIG_RISCV_M_MODE) += traps_misaligned.o > > obj-$(CONFIG_FPU) += fpu.o > > obj-$(CONFIG_SMP) += smpboot.o > > diff --git a/arch/riscv/kernel/efi-header.S b/arch/riscv/kernel/efi-header.S > > new file mode 100644 > > index 000000000000..822b4c9ff2bb > > --- /dev/null > > +++ b/arch/riscv/kernel/efi-header.S > > @@ -0,0 +1,104 @@ > > +/* SPDX-License-Identifier: GPL-2.0-only */ > > +/* > > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > > + * Adapted from arch/arm64/kernel/efi-header.S > > + */ > > + > > +#include > > +#include > > + > > + .macro __EFI_PE_HEADER > > + .long PE_MAGIC > > +coff_header: > > +#ifdef CONFIG_64BIT > > + .short IMAGE_FILE_MACHINE_RISCV64 // Machine > > +#else > > + .short IMAGE_FILE_MACHINE_RISCV32 // Machine > > +#endif > > + .short section_count // NumberOfSections > > + .long 0 // TimeDateStamp > > + .long 0 // PointerToSymbolTable > > + .long 0 // NumberOfSymbols > > + .short section_table - optional_header // SizeOfOptionalHeader > > + .short IMAGE_FILE_DEBUG_STRIPPED | \ > > + IMAGE_FILE_EXECUTABLE_IMAGE | \ > > + IMAGE_FILE_LINE_NUMS_STRIPPED // Characteristics > > + > > +optional_header: > > + .short PE_OPT_MAGIC_PE32PLUS // PE32+ format > > Are you sure both riscv32 and riscv64 use PE32+? IIUC, 32-bit > architectures use PE32 not PE32+ (but I could be wrong) > Ahh yes. You are correct. Thanks for noticing it. I just followed the U-Boot implementation [1]. I will update this in the next revision and update the U-Boot code as well. As per the specification, we also need to add a BaseOfData[2] entry for RV32. Does any of the efi application loader actually use BaseOfData or can we set it to zero for RV32 ? [1] https://gitlab.denx.de/u-boot/custodians/u-boot-amlogic/-/blob/u-boot-amlogic/arch/riscv/lib/crt0_riscv_efi.S#L51 [2] https://docs.microsoft.com/en-us/windows/win32/debug/pe-format > > + .byte 0x02 // MajorLinkerVersion > > + .byte 0x14 // MinorLinkerVersion > > + .long __pecoff_text_end - efi_header_end // SizeOfCode > > + .long __pecoff_data_virt_size // SizeOfInitializedData > > + .long 0 // SizeOfUninitializedData > > + .long __efistub_efi_pe_entry - _start // AddressOfEntryPoint > > + .long efi_header_end - _start // BaseOfCode > > + > > +extra_header_fields: > > + .quad 0 // ImageBase > > + .long PECOFF_SECTION_ALIGNMENT // SectionAlignment > > + .long PECOFF_FILE_ALIGNMENT // FileAlignment > > + .short 0 // MajorOperatingSystemVersion > > + .short 0 // MinorOperatingSystemVersion > > + .short LINUX_EFISTUB_MAJOR_VERSION // MajorImageVersion > > + .short LINUX_EFISTUB_MINOR_VERSION // MinorImageVersion > > + .short 0 // MajorSubsystemVersion > > + .short 0 // MinorSubsystemVersion > > + .long 0 // Win32VersionValue > > + > > + .long _end - _start // SizeOfImage > > + > > + // Everything before the kernel image is considered part of the header > > + .long efi_header_end - _start // SizeOfHeaders > > + .long 0 // CheckSum > > + .short IMAGE_SUBSYSTEM_EFI_APPLICATION // Subsystem > > + .short 0 // DllCharacteristics > > + .quad 0 // SizeOfStackReserve > > + .quad 0 // SizeOfStackCommit > > + .quad 0 // SizeOfHeapReserve > > + .quad 0 // SizeOfHeapCommit > > + .long 0 // LoaderFlags > > + .long (section_table - .) / 8 // NumberOfRvaAndSizes > > + > > + .quad 0 // ExportTable > > + .quad 0 // ImportTable > > + .quad 0 // ResourceTable > > + .quad 0 // ExceptionTable > > + .quad 0 // CertificationTable > > + .quad 0 // BaseRelocationTable > > + > > + // Section table > > +section_table: > > + .ascii ".text\0\0\0" > > + .long __pecoff_text_end - efi_header_end // VirtualSize > > + .long efi_header_end - _start // VirtualAddress > > + .long __pecoff_text_end - efi_header_end // SizeOfRawData > > + .long efi_header_end - _start // PointerToRawData > > + > > + .long 0 // PointerToRelocations > > + .long 0 // PointerToLineNumbers > > + .short 0 // NumberOfRelocations > > + .short 0 // NumberOfLineNumbers > > + .long IMAGE_SCN_CNT_CODE | \ > > + IMAGE_SCN_MEM_READ | \ > > + IMAGE_SCN_MEM_EXECUTE // Characteristics > > + > > + .ascii ".data\0\0\0" > > + .long __pecoff_data_virt_size // VirtualSize > > + .long __pecoff_text_end - _start // VirtualAddress > > + .long __pecoff_data_raw_size // SizeOfRawData > > + .long __pecoff_text_end - _start // PointerToRawData > > + > > + .long 0 // PointerToRelocations > > + .long 0 // PointerToLineNumbers > > + .short 0 // NumberOfRelocations > > + .short 0 // NumberOfLineNumbers > > + .long IMAGE_SCN_CNT_INITIALIZED_DATA | \ > > + IMAGE_SCN_MEM_READ | \ > > + IMAGE_SCN_MEM_WRITE // Characteristics > > + > > + .set section_count, (. - section_table) / 40 > > + > > + .balign 0x1000 > > +efi_header_end: > > + .endm > > diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S > > index c6a37e8231a8..3631147732ee 100644 > > --- a/arch/riscv/kernel/head.S > > +++ b/arch/riscv/kernel/head.S > > @@ -13,6 +13,7 @@ > > #include > > #include > > #include > > +#include "efi-header.S" > > > > __HEAD > > ENTRY(_start) > > @@ -22,10 +23,18 @@ ENTRY(_start) > > * Do not modify it without modifying the structure and all bootloaders > > * that expects this header format!! > > */ > > +#ifdef CONFIG_EFI > > + /* > > + * This instruction decodes to "MZ" ASCII required by UEFI. > > + */ > > + c.li s4,-13 > > + j _start_kernel > > +#else > > /* jump to start kernel */ > > j _start_kernel > > /* reserved */ > > .word 0 > > +#endif > > .balign 8 > > #if __riscv_xlen == 64 > > /* Image load offset(2MB) from start of RAM */ > > @@ -43,7 +52,14 @@ ENTRY(_start) > > .ascii RISCV_IMAGE_MAGIC > > .balign 4 > > .ascii RISCV_IMAGE_MAGIC2 > > +#ifdef CONFIG_EFI > > + .word pe_head_start - _start > > +pe_head_start: > > + > > + __EFI_PE_HEADER > > +#else > > .word 0 > > +#endif > > > > .align 2 > > #ifdef CONFIG_MMU > > diff --git a/arch/riscv/kernel/image-vars.h b/arch/riscv/kernel/image-vars.h > > new file mode 100644 > > index 000000000000..8c212efb37a6 > > --- /dev/null > > +++ b/arch/riscv/kernel/image-vars.h > > @@ -0,0 +1,51 @@ > > +/* SPDX-License-Identifier: GPL-2.0-only */ > > +/* > > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > > + * Linker script variables to be set after section resolution, as > > + * ld.lld does not like variables assigned before SECTIONS is processed. > > + * Based on arch/arm64/kerne/image-vars.h > > + */ > > +#ifndef __RISCV_KERNEL_IMAGE_VARS_H > > +#define __RISCV_KERNEL_IMAGE_VARS_H > > + > > +#ifndef LINKER_SCRIPT > > +#error This file should only be included in vmlinux.lds.S > > +#endif > > + > > +#ifdef CONFIG_EFI > > + > > +/* > > + * The EFI stub has its own symbol namespace prefixed by __efistub_, to > > + * isolate it from the kernel proper. The following symbols are legally > > + * accessed by the stub, so provide some aliases to make them accessible. > > + * Only include data symbols here, or text symbols of functions that are > > + * guaranteed to be safe when executed at another offset than they were > > + * linked at. The routines below are all implemented in assembler in a > > + * position independent manner > > + */ > > +__efistub_memcmp = memcmp; > > +__efistub_memchr = memchr; > > +__efistub_memcpy = memcpy; > > +__efistub_memmove = memmove; > > +__efistub_memset = memset; > > +__efistub_strlen = strlen; > > +__efistub_strnlen = strnlen; > > +__efistub_strcmp = strcmp; > > +__efistub_strncmp = strncmp; > > +__efistub_strrchr = strrchr; > > + > > +#ifdef CONFIG_KASAN > > +__efistub___memcpy = memcpy; > > +__efistub___memmove = memmove; > > +__efistub___memset = memset; > > +#endif > > + > > +__efistub__start = _start; > > +__efistub__start_kernel = _start_kernel; > > +__efistub__end = _end; > > +__efistub__edata = _edata; > > +__efistub_screen_info = screen_info; > > + > > +#endif > > + > > +#endif /* __RISCV_KERNEL_IMAGE_VARS_H */ > > diff --git a/arch/riscv/kernel/vmlinux.lds.S b/arch/riscv/kernel/vmlinux.lds.S > > index f3586e31ed1e..6dcf790282dd 100644 > > --- a/arch/riscv/kernel/vmlinux.lds.S > > +++ b/arch/riscv/kernel/vmlinux.lds.S > > @@ -10,6 +10,7 @@ > > #include > > #include > > #include > > +#include "image-vars.h" > > > > #include > > OUTPUT_ARCH(riscv) > > @@ -17,6 +18,9 @@ ENTRY(_start) > > > > jiffies = jiffies_64; > > > > +PECOFF_SECTION_ALIGNMENT = 0x1000; > > +PECOFF_FILE_ALIGNMENT = 0x200; > > + > > SECTIONS > > { > > /* Beginning of code and text segment */ > > @@ -76,6 +80,10 @@ SECTIONS > > > > EXCEPTION_TABLE(0x10) > > > > +#ifdef CONFIG_EFI > > + . = ALIGN(PECOFF_SECTION_ALIGNMENT); > > + __pecoff_text_end = .; > > +#endif > > . = ALIGN(SECTION_ALIGN); > > _data = .; > > > > @@ -83,16 +91,26 @@ SECTIONS > > .sdata : { > > __global_pointer$ = . + 0x800; > > *(.sdata*) > > - /* End of data section */ > > - _edata = .; > > } > > > > +#ifdef CONFIG_EFI > > + .pecoff_edata_padding : { BYTE(0); . = ALIGN(PECOFF_FILE_ALIGNMENT); } > > + __pecoff_data_raw_size = ABSOLUTE(. - __pecoff_text_end); > > +#endif > > + > > + /* End of data section */ > > + _edata = .; > > + > > BSS_SECTION(PAGE_SIZE, PAGE_SIZE, 0) > > > > .rel.dyn : { > > *(.rel.dyn*) > > } > > > > +#ifdef CONFIG_EFI > > + . = ALIGN(PECOFF_SECTION_ALIGNMENT); > > + __pecoff_data_virt_size = ABSOLUTE(. - __pecoff_text_end); > > +#endif > > _end = .; > > > > STABS_DEBUG > > -- > > 2.24.0 > > > > _______________________________________________ > linux-riscv mailing list > linux-riscv@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-riscv -- Regards, Atish From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 388A2C43461 for ; Sat, 12 Sep 2020 02:04:51 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5A92D221E5 for ; 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Fri, 11 Sep 2020 19:04:22 -0700 (PDT) MIME-Version: 1.0 References: <20200828172036.8056-1-atish.patra@wdc.com> <20200828172036.8056-6-atish.patra@wdc.com> In-Reply-To: From: Atish Patra Date: Fri, 11 Sep 2020 19:04:11 -0700 Message-ID: Subject: Re: [PATCH v7 5/9] RISC-V: Add PE/COFF header for EFI stub To: Ard Biesheuvel X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200911_220428_498831_B6D84A88 X-CRM114-Status: GOOD ( 35.49 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-efi , Anup Patel , Masahiro Yamada , Anup Patel , Nick Desaulniers , Linux Kernel Mailing List , Ingo Molnar , Atish Patra , Arvind Sankar , Palmer Dabbelt , Paul Walmsley , Alistair Francis , linux-riscv , Greentime Hu , Mike Rapoport Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org On Fri, Sep 11, 2020 at 6:09 AM Ard Biesheuvel wrote: > > On Fri, 28 Aug 2020 at 20:20, Atish Patra wrote: > > > > Linux kernel Image can appear as an EFI application With appropriate > > PE/COFF header fields in the beginning of the Image header. An EFI > > application loader can directly load a Linux kernel Image and an EFI > > stub residing in kernel can boot Linux kernel directly. > > > > Add the necessary PE/COFF header. > > > > Signed-off-by: Atish Patra > > Link: https://lore.kernel.org/r/20200421033336.9663-3-atish.patra@wdc.com > > [ardb: - use C prefix for c.li to ensure the expected opcode is emitted > > - align all image sections according to PE/COFF section alignment ] > > Signed-off-by: Ard Biesheuvel > > Reviewed-by: Anup Patel > > Since you need to respin this anyway, one comment below on a thing > that I spotted while revisiting these patches. > > > --- > > arch/riscv/include/asm/sections.h | 13 ++++ > > arch/riscv/kernel/Makefile | 4 ++ > > arch/riscv/kernel/efi-header.S | 104 ++++++++++++++++++++++++++++++ > > arch/riscv/kernel/head.S | 16 +++++ > > arch/riscv/kernel/image-vars.h | 51 +++++++++++++++ > > arch/riscv/kernel/vmlinux.lds.S | 22 ++++++- > > 6 files changed, 208 insertions(+), 2 deletions(-) > > create mode 100644 arch/riscv/include/asm/sections.h > > create mode 100644 arch/riscv/kernel/efi-header.S > > create mode 100644 arch/riscv/kernel/image-vars.h > > > > diff --git a/arch/riscv/include/asm/sections.h b/arch/riscv/include/asm/sections.h > > new file mode 100644 > > index 000000000000..3a9971b1210f > > --- /dev/null > > +++ b/arch/riscv/include/asm/sections.h > > @@ -0,0 +1,13 @@ > > +/* SPDX-License-Identifier: GPL-2.0-only */ > > +/* > > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > > + */ > > +#ifndef __ASM_SECTIONS_H > > +#define __ASM_SECTIONS_H > > + > > +#include > > + > > +extern char _start[]; > > +extern char _start_kernel[]; > > + > > +#endif /* __ASM_SECTIONS_H */ > > diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile > > index dc93710f0b2f..41e3895a3192 100644 > > --- a/arch/riscv/kernel/Makefile > > +++ b/arch/riscv/kernel/Makefile > > @@ -31,6 +31,10 @@ obj-y += cacheinfo.o > > obj-y += patch.o > > obj-$(CONFIG_MMU) += vdso.o vdso/ > > > > +OBJCOPYFLAGS := --prefix-symbols=__efistub_ > > +$(obj)/%.stub.o: $(obj)/%.o FORCE > > + $(call if_changed,objcopy) > > + > > obj-$(CONFIG_RISCV_M_MODE) += traps_misaligned.o > > obj-$(CONFIG_FPU) += fpu.o > > obj-$(CONFIG_SMP) += smpboot.o > > diff --git a/arch/riscv/kernel/efi-header.S b/arch/riscv/kernel/efi-header.S > > new file mode 100644 > > index 000000000000..822b4c9ff2bb > > --- /dev/null > > +++ b/arch/riscv/kernel/efi-header.S > > @@ -0,0 +1,104 @@ > > +/* SPDX-License-Identifier: GPL-2.0-only */ > > +/* > > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > > + * Adapted from arch/arm64/kernel/efi-header.S > > + */ > > + > > +#include > > +#include > > + > > + .macro __EFI_PE_HEADER > > + .long PE_MAGIC > > +coff_header: > > +#ifdef CONFIG_64BIT > > + .short IMAGE_FILE_MACHINE_RISCV64 // Machine > > +#else > > + .short IMAGE_FILE_MACHINE_RISCV32 // Machine > > +#endif > > + .short section_count // NumberOfSections > > + .long 0 // TimeDateStamp > > + .long 0 // PointerToSymbolTable > > + .long 0 // NumberOfSymbols > > + .short section_table - optional_header // SizeOfOptionalHeader > > + .short IMAGE_FILE_DEBUG_STRIPPED | \ > > + IMAGE_FILE_EXECUTABLE_IMAGE | \ > > + IMAGE_FILE_LINE_NUMS_STRIPPED // Characteristics > > + > > +optional_header: > > + .short PE_OPT_MAGIC_PE32PLUS // PE32+ format > > Are you sure both riscv32 and riscv64 use PE32+? IIUC, 32-bit > architectures use PE32 not PE32+ (but I could be wrong) > Ahh yes. You are correct. Thanks for noticing it. I just followed the U-Boot implementation [1]. I will update this in the next revision and update the U-Boot code as well. As per the specification, we also need to add a BaseOfData[2] entry for RV32. Does any of the efi application loader actually use BaseOfData or can we set it to zero for RV32 ? [1] https://gitlab.denx.de/u-boot/custodians/u-boot-amlogic/-/blob/u-boot-amlogic/arch/riscv/lib/crt0_riscv_efi.S#L51 [2] https://docs.microsoft.com/en-us/windows/win32/debug/pe-format > > + .byte 0x02 // MajorLinkerVersion > > + .byte 0x14 // MinorLinkerVersion > > + .long __pecoff_text_end - efi_header_end // SizeOfCode > > + .long __pecoff_data_virt_size // SizeOfInitializedData > > + .long 0 // SizeOfUninitializedData > > + .long __efistub_efi_pe_entry - _start // AddressOfEntryPoint > > + .long efi_header_end - _start // BaseOfCode > > + > > +extra_header_fields: > > + .quad 0 // ImageBase > > + .long PECOFF_SECTION_ALIGNMENT // SectionAlignment > > + .long PECOFF_FILE_ALIGNMENT // FileAlignment > > + .short 0 // MajorOperatingSystemVersion > > + .short 0 // MinorOperatingSystemVersion > > + .short LINUX_EFISTUB_MAJOR_VERSION // MajorImageVersion > > + .short LINUX_EFISTUB_MINOR_VERSION // MinorImageVersion > > + .short 0 // MajorSubsystemVersion > > + .short 0 // MinorSubsystemVersion > > + .long 0 // Win32VersionValue > > + > > + .long _end - _start // SizeOfImage > > + > > + // Everything before the kernel image is considered part of the header > > + .long efi_header_end - _start // SizeOfHeaders > > + .long 0 // CheckSum > > + .short IMAGE_SUBSYSTEM_EFI_APPLICATION // Subsystem > > + .short 0 // DllCharacteristics > > + .quad 0 // SizeOfStackReserve > > + .quad 0 // SizeOfStackCommit > > + .quad 0 // SizeOfHeapReserve > > + .quad 0 // SizeOfHeapCommit > > + .long 0 // LoaderFlags > > + .long (section_table - .) / 8 // NumberOfRvaAndSizes > > + > > + .quad 0 // ExportTable > > + .quad 0 // ImportTable > > + .quad 0 // ResourceTable > > + .quad 0 // ExceptionTable > > + .quad 0 // CertificationTable > > + .quad 0 // BaseRelocationTable > > + > > + // Section table > > +section_table: > > + .ascii ".text\0\0\0" > > + .long __pecoff_text_end - efi_header_end // VirtualSize > > + .long efi_header_end - _start // VirtualAddress > > + .long __pecoff_text_end - efi_header_end // SizeOfRawData > > + .long efi_header_end - _start // PointerToRawData > > + > > + .long 0 // PointerToRelocations > > + .long 0 // PointerToLineNumbers > > + .short 0 // NumberOfRelocations > > + .short 0 // NumberOfLineNumbers > > + .long IMAGE_SCN_CNT_CODE | \ > > + IMAGE_SCN_MEM_READ | \ > > + IMAGE_SCN_MEM_EXECUTE // Characteristics > > + > > + .ascii ".data\0\0\0" > > + .long __pecoff_data_virt_size // VirtualSize > > + .long __pecoff_text_end - _start // VirtualAddress > > + .long __pecoff_data_raw_size // SizeOfRawData > > + .long __pecoff_text_end - _start // PointerToRawData > > + > > + .long 0 // PointerToRelocations > > + .long 0 // PointerToLineNumbers > > + .short 0 // NumberOfRelocations > > + .short 0 // NumberOfLineNumbers > > + .long IMAGE_SCN_CNT_INITIALIZED_DATA | \ > > + IMAGE_SCN_MEM_READ | \ > > + IMAGE_SCN_MEM_WRITE // Characteristics > > + > > + .set section_count, (. - section_table) / 40 > > + > > + .balign 0x1000 > > +efi_header_end: > > + .endm > > diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S > > index c6a37e8231a8..3631147732ee 100644 > > --- a/arch/riscv/kernel/head.S > > +++ b/arch/riscv/kernel/head.S > > @@ -13,6 +13,7 @@ > > #include > > #include > > #include > > +#include "efi-header.S" > > > > __HEAD > > ENTRY(_start) > > @@ -22,10 +23,18 @@ ENTRY(_start) > > * Do not modify it without modifying the structure and all bootloaders > > * that expects this header format!! > > */ > > +#ifdef CONFIG_EFI > > + /* > > + * This instruction decodes to "MZ" ASCII required by UEFI. > > + */ > > + c.li s4,-13 > > + j _start_kernel > > +#else > > /* jump to start kernel */ > > j _start_kernel > > /* reserved */ > > .word 0 > > +#endif > > .balign 8 > > #if __riscv_xlen == 64 > > /* Image load offset(2MB) from start of RAM */ > > @@ -43,7 +52,14 @@ ENTRY(_start) > > .ascii RISCV_IMAGE_MAGIC > > .balign 4 > > .ascii RISCV_IMAGE_MAGIC2 > > +#ifdef CONFIG_EFI > > + .word pe_head_start - _start > > +pe_head_start: > > + > > + __EFI_PE_HEADER > > +#else > > .word 0 > > +#endif > > > > .align 2 > > #ifdef CONFIG_MMU > > diff --git a/arch/riscv/kernel/image-vars.h b/arch/riscv/kernel/image-vars.h > > new file mode 100644 > > index 000000000000..8c212efb37a6 > > --- /dev/null > > +++ b/arch/riscv/kernel/image-vars.h > > @@ -0,0 +1,51 @@ > > +/* SPDX-License-Identifier: GPL-2.0-only */ > > +/* > > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > > + * Linker script variables to be set after section resolution, as > > + * ld.lld does not like variables assigned before SECTIONS is processed. > > + * Based on arch/arm64/kerne/image-vars.h > > + */ > > +#ifndef __RISCV_KERNEL_IMAGE_VARS_H > > +#define __RISCV_KERNEL_IMAGE_VARS_H > > + > > +#ifndef LINKER_SCRIPT > > +#error This file should only be included in vmlinux.lds.S > > +#endif > > + > > +#ifdef CONFIG_EFI > > + > > +/* > > + * The EFI stub has its own symbol namespace prefixed by __efistub_, to > > + * isolate it from the kernel proper. The following symbols are legally > > + * accessed by the stub, so provide some aliases to make them accessible. > > + * Only include data symbols here, or text symbols of functions that are > > + * guaranteed to be safe when executed at another offset than they were > > + * linked at. The routines below are all implemented in assembler in a > > + * position independent manner > > + */ > > +__efistub_memcmp = memcmp; > > +__efistub_memchr = memchr; > > +__efistub_memcpy = memcpy; > > +__efistub_memmove = memmove; > > +__efistub_memset = memset; > > +__efistub_strlen = strlen; > > +__efistub_strnlen = strnlen; > > +__efistub_strcmp = strcmp; > > +__efistub_strncmp = strncmp; > > +__efistub_strrchr = strrchr; > > + > > +#ifdef CONFIG_KASAN > > +__efistub___memcpy = memcpy; > > +__efistub___memmove = memmove; > > +__efistub___memset = memset; > > +#endif > > + > > +__efistub__start = _start; > > +__efistub__start_kernel = _start_kernel; > > +__efistub__end = _end; > > +__efistub__edata = _edata; > > +__efistub_screen_info = screen_info; > > + > > +#endif > > + > > +#endif /* __RISCV_KERNEL_IMAGE_VARS_H */ > > diff --git a/arch/riscv/kernel/vmlinux.lds.S b/arch/riscv/kernel/vmlinux.lds.S > > index f3586e31ed1e..6dcf790282dd 100644 > > --- a/arch/riscv/kernel/vmlinux.lds.S > > +++ b/arch/riscv/kernel/vmlinux.lds.S > > @@ -10,6 +10,7 @@ > > #include > > #include > > #include > > +#include "image-vars.h" > > > > #include > > OUTPUT_ARCH(riscv) > > @@ -17,6 +18,9 @@ ENTRY(_start) > > > > jiffies = jiffies_64; > > > > +PECOFF_SECTION_ALIGNMENT = 0x1000; > > +PECOFF_FILE_ALIGNMENT = 0x200; > > + > > SECTIONS > > { > > /* Beginning of code and text segment */ > > @@ -76,6 +80,10 @@ SECTIONS > > > > EXCEPTION_TABLE(0x10) > > > > +#ifdef CONFIG_EFI > > + . = ALIGN(PECOFF_SECTION_ALIGNMENT); > > + __pecoff_text_end = .; > > +#endif > > . = ALIGN(SECTION_ALIGN); > > _data = .; > > > > @@ -83,16 +91,26 @@ SECTIONS > > .sdata : { > > __global_pointer$ = . + 0x800; > > *(.sdata*) > > - /* End of data section */ > > - _edata = .; > > } > > > > +#ifdef CONFIG_EFI > > + .pecoff_edata_padding : { BYTE(0); . = ALIGN(PECOFF_FILE_ALIGNMENT); } > > + __pecoff_data_raw_size = ABSOLUTE(. - __pecoff_text_end); > > +#endif > > + > > + /* End of data section */ > > + _edata = .; > > + > > BSS_SECTION(PAGE_SIZE, PAGE_SIZE, 0) > > > > .rel.dyn : { > > *(.rel.dyn*) > > } > > > > +#ifdef CONFIG_EFI > > + . = ALIGN(PECOFF_SECTION_ALIGNMENT); > > + __pecoff_data_virt_size = ABSOLUTE(. - __pecoff_text_end); > > +#endif > > _end = .; > > > > STABS_DEBUG > > -- > > 2.24.0 > > > > _______________________________________________ > linux-riscv mailing list > linux-riscv@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-riscv -- Regards, Atish _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv