From patchwork Tue Apr 21 03:33:36 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Atish Patra X-Patchwork-Id: 206402 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=-9.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT 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 CA0BBC2BA19 for ; Tue, 21 Apr 2020 03:34:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A587B2084D for ; Tue, 21 Apr 2020 03:34:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=wdc.com header.i=@wdc.com header.b="mjLAB/GB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728178AbgDUDeo (ORCPT ); Mon, 20 Apr 2020 23:34:44 -0400 Received: from esa4.hgst.iphmx.com ([216.71.154.42]:10951 "EHLO esa4.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726793AbgDUDen (ORCPT ); Mon, 20 Apr 2020 23:34:43 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=wdc.com; i=@wdc.com; q=dns/txt; s=dkim.wdc.com; t=1587440082; x=1618976082; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=tJnNH5jB5LYvd4sUzHq0FJMX11DGIdD0e04H+JXXoQo=; b=mjLAB/GBbWP5HOs2+RHfSkA2X5G8QhJ/HnbXxj+UbRvaK4BC1Ktf0xbh rQjAElhiLDjx6umTbzZ7k9M6uoyM2oeQB6eKOR/PIDH/zq9XxjvxIlg1D st7K3FSGw1UrxPDOL7+xRdsfxAt4ExDqGxJch2M69YKZZxrKBLb9ilK9Y 4NNEfbSZxjni9QIQ5FngmeiqTZ8WWKiHpSFypZQijriwN/f9eTN2tqIMD WsIELv44GOjyOwS46qhkTmUlDVKOd+5EaKMNxsqX1TH7IamqA2ALQG/T7 Z62X3DjRA3s8mcUOUB5WbbQy6wBzERkrquyY5y2MxqnpJinbes1JkvVxV Q==; IronPort-SDR: TNguCPfGvVV4RLbGSUBxuDltmuqq2fm41lcJ6u3YePE9E7yeggeLLnuMWv5ROLPex1ylGDZsaG qo25dHPAeaH4cFUMRNbFe3NRI+MyuQIeUjuTkV4x/G0Lfnnd2vKSGs0ejuoTefn2zTU0ck+SMu P0qcGKd02VX23sR4liZWc5sHGBVzG3Feb+VO7Twsr4FDVBXfZuM8a+nD4puXHUIHT6/PKcBE8W Txtn8V0ylrMkVdjeVyNjvRDya4qbMibds34p9yNOke7TMVkEwXJe/LxbTCRy5ISNROWxcTmpQV JVc= X-IronPort-AV: E=Sophos;i="5.72,408,1580745600"; d="scan'208";a="135760538" Received: from uls-op-cesaip01.wdc.com (HELO uls-op-cesaep01.wdc.com) ([199.255.45.14]) by ob1.hgst.iphmx.com with ESMTP; 21 Apr 2020 11:34:41 +0800 IronPort-SDR: NOmf5fitcwrkbgosMAk2T5mg2+y+trXUT3pu4vLlRYI6FoY0sES3kmzBydssLjwmATKYzziwDz jdzFu5ajsPCKW02Am0SJSz/o8mo59foOA= Received: from uls-op-cesaip01.wdc.com ([10.248.3.36]) by uls-op-cesaep01.wdc.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Apr 2020 20:25:33 -0700 IronPort-SDR: COuMV9HYbF4USsGsyykA2YMeSPiVjylaMfhthnkLeYFnyMK73n7wWfoSNEgxorgf1cKP/z89cg M4RskHavfXeA== WDCIronportException: Internal Received: from hqe220030.ad.shared (HELO jedi-01.hgst.com) ([10.86.56.34]) by uls-op-cesaip01.wdc.com with ESMTP; 20 Apr 2020 20:34:42 -0700 From: Atish Patra To: linux-kernel@vger.kernel.org Cc: Atish Patra , Ard Biesheuvel , linux-efi@vger.kernel.org, linux-riscv@lists.infradead.org, Masahiro Yamada , Palmer Dabbelt , Heinrich Schuchardt Subject: [v4 PATCH 3/3] RISC-V: Add EFI stub support. Date: Mon, 20 Apr 2020 20:33:36 -0700 Message-Id: <20200421033336.9663-4-atish.patra@wdc.com> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20200421033336.9663-1-atish.patra@wdc.com> References: <20200421033336.9663-1-atish.patra@wdc.com> MIME-Version: 1.0 Sender: linux-efi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org Add a RISC-V architecture specific stub code that actually copies the actual kernel image to a valid address and jump to it after boot services are terminated. Enable UEFI related kernel configs as well for RISC-V. Signed-off-by: Atish Patra --- arch/riscv/Kconfig | 20 ++++ arch/riscv/Makefile | 1 + arch/riscv/configs/defconfig | 1 + arch/riscv/include/asm/efi.h | 44 +++++++++ drivers/firmware/efi/Kconfig | 2 +- drivers/firmware/efi/libstub/Makefile | 10 ++ drivers/firmware/efi/libstub/riscv-stub.c | 106 ++++++++++++++++++++++ 7 files changed, 183 insertions(+), 1 deletion(-) create mode 100644 arch/riscv/include/asm/efi.h create mode 100644 drivers/firmware/efi/libstub/riscv-stub.c diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index f39e326a7a42..eb4f41c8f3ce 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -379,10 +379,30 @@ config CMDLINE_FORCE endchoice +config EFI_STUB + bool + +config EFI + bool "UEFI runtime support" + depends on OF + select LIBFDT + select UCS2_STRING + select EFI_PARAMS_FROM_FDT + select EFI_STUB + select EFI_GENERIC_STUB + default y + help + This option provides support for runtime services provided + by UEFI firmware (such as non-volatile variables, realtime + clock, and platform reset). A UEFI stub is also provided to + allow the kernel to be booted as an EFI application. This + is only useful on systems that have UEFI firmware. + endmenu menu "Power management options" source "kernel/power/Kconfig" +source "drivers/firmware/Kconfig" endmenu diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile index fb6e37db836d..079435804d6d 100644 --- a/arch/riscv/Makefile +++ b/arch/riscv/Makefile @@ -80,6 +80,7 @@ head-y := arch/riscv/kernel/head.o core-y += arch/riscv/ libs-y += arch/riscv/lib/ +core-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a PHONY += vdso_install vdso_install: diff --git a/arch/riscv/configs/defconfig b/arch/riscv/configs/defconfig index 4da4886246a4..ae69e12d306a 100644 --- a/arch/riscv/configs/defconfig +++ b/arch/riscv/configs/defconfig @@ -129,3 +129,4 @@ CONFIG_DEBUG_BLOCK_EXT_DEVT=y # CONFIG_RUNTIME_TESTING_MENU is not set CONFIG_MEMTEST=y # CONFIG_SYSFS_SYSCALL is not set +CONFIG_EFI=y diff --git a/arch/riscv/include/asm/efi.h b/arch/riscv/include/asm/efi.h new file mode 100644 index 000000000000..62d7d5eafed8 --- /dev/null +++ b/arch/riscv/include/asm/efi.h @@ -0,0 +1,44 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2020 Western Digital Corporation or its affiliates. + * Based on arch/arm64/include/asm/efi.h + */ +#ifndef _ASM_EFI_H +#define _ASM_EFI_H + +#include +#include +#include +#include + +#define VA_BITS_MIN 39 + +/* on RISC-V, the FDT may be located anywhere in system RAM */ +static inline unsigned long efi_get_max_fdt_addr(unsigned long dram_base) +{ + return ULONG_MAX; +} + +/* Load initrd at enough distance from DRAM start */ +static inline unsigned long efi_get_max_initrd_addr(unsigned long dram_base, + unsigned long image_addr) +{ + return dram_base + SZ_256M; +} + +#define efi_bs_call(func, ...) efi_system_table()->boottime->func(__VA_ARGS__) +#define efi_rt_call(func, ...) efi_system_table()->runtime->func(__VA_ARGS__) +#define efi_is_native() (true) + +#define efi_table_attr(inst, attr) (inst->attr) + +#define efi_call_proto(inst, func, ...) inst->func(inst, ##__VA_ARGS__) + +#define alloc_screen_info(x...) (&screen_info) +extern char stext_offset[]; + +static inline void free_screen_info(struct screen_info *si) +{ +} + +#endif /* _ASM_EFI_H */ diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig index 2a2b2b96a1dc..fcdc789d3f87 100644 --- a/drivers/firmware/efi/Kconfig +++ b/drivers/firmware/efi/Kconfig @@ -111,7 +111,7 @@ config EFI_GENERIC_STUB config EFI_ARMSTUB_DTB_LOADER bool "Enable the DTB loader" - depends on EFI_GENERIC_STUB + depends on EFI_GENERIC_STUB && !RISCV default y help Select this config option to add support for the dtb= command diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile index 0f57293d777e..eb365c55c0fe 100644 --- a/drivers/firmware/efi/libstub/Makefile +++ b/drivers/firmware/efi/libstub/Makefile @@ -22,6 +22,8 @@ cflags-$(CONFIG_ARM64) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ cflags-$(CONFIG_ARM) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ -fno-builtin -fpic \ $(call cc-option,-mno-single-pic-base) +cflags-$(CONFIG_RISCV) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ + -fpic cflags-$(CONFIG_EFI_GENERIC_STUB) += -I$(srctree)/scripts/dtc/libfdt @@ -57,6 +59,7 @@ lib-$(CONFIG_EFI_GENERIC_STUB) += efi-stub.o fdt.o string.o \ lib-$(CONFIG_ARM) += arm32-stub.o lib-$(CONFIG_ARM64) += arm64-stub.o lib-$(CONFIG_X86) += x86-stub.o +lib-$(CONFIG_RISCV) += riscv-stub.o CFLAGS_arm32-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET) CFLAGS_arm64-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET) @@ -100,6 +103,13 @@ STUBCOPY_FLAGS-$(CONFIG_X86) += --rename-section .bss=.bss.efistub,load,alloc STUBCOPY_RELOC-$(CONFIG_X86_32) := R_386_32 STUBCOPY_RELOC-$(CONFIG_X86_64) := R_X86_64_64 +# For RISC-V, we don't need anything special other than arm64. Keep all the +# symbols in .init section and make sure that no absolute symbols references +# doesn't exist. +STUBCOPY_FLAGS-$(CONFIG_RISCV) += --prefix-alloc-sections=.init \ + --prefix-symbols=__efistub_ +STUBCOPY_RELOC-$(CONFIG_RISCV) := R_RISCV_HI20 + $(obj)/%.stub.o: $(obj)/%.o FORCE $(call if_changed,stubcopy) diff --git a/drivers/firmware/efi/libstub/riscv-stub.c b/drivers/firmware/efi/libstub/riscv-stub.c new file mode 100644 index 000000000000..bd1d6fed8754 --- /dev/null +++ b/drivers/firmware/efi/libstub/riscv-stub.c @@ -0,0 +1,106 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2013, 2014 Linaro Ltd; + * Copyright (C) 2020 Western Digital Corporation or its affiliates. + * + * This file implements the EFI boot stub for the RISC-V kernel. + * Adapted from ARM64 version at drivers/firmware/efi/libstub/arm64-stub.c. + */ + +#include +#include +#include +#include +#include + +#include "efistub.h" +/* + * RISC-V requires the kernel image to placed 2 MB aligned base for 64 bit and + * 4MB for 32 bit. + */ +#ifdef CONFIG_64BIT +#define MIN_KIMG_ALIGN SZ_2M +#else +#define MIN_KIMG_ALIGN SZ_4M +#endif + +typedef __attribute__((noreturn)) void (*jump_kernel_func)(unsigned int, + unsigned long); +efi_status_t check_platform_features(void) +{ + return EFI_SUCCESS; +} + +static u32 get_boot_hartid_from_fdt(unsigned long fdt) +{ + int chosen_node, len; + const fdt32_t *prop; + + chosen_node = fdt_path_offset((void *)fdt, "/chosen"); + if (chosen_node < 0) + return U32_MAX; + prop = fdt_getprop((void *)fdt, chosen_node, "boot-hartid", &len); + if (!prop || len != sizeof(u32)) + return U32_MAX; + + return fdt32_to_cpu(*prop); +} + +/* + * Jump to real kernel here with following constraints. + * 1. MMU should be disabled. + * 2. a0 should contain hartid + * 3. a1 should DT address + */ +void __noreturn efi_enter_kernel(unsigned long entrypoint, unsigned long fdt, + unsigned long fdt_size) +{ + unsigned long kernel_entry = entrypoint + (unsigned long)stext_offset; + jump_kernel_func jump_kernel = (jump_kernel_func) kernel_entry; + u32 hartid = get_boot_hartid_from_fdt(fdt); + + if (hartid == U32_MAX) + /* We can not use panic or BUG at this point */ + __asm__ __volatile__ ("ebreak"); + /* Disable MMU */ + csr_write(CSR_SATP, 0); + jump_kernel(hartid, fdt); +} + +efi_status_t handle_kernel_image(unsigned long *image_addr, + unsigned long *image_size, + unsigned long *reserve_addr, + unsigned long *reserve_size, + unsigned long dram_base, + efi_loaded_image_t *image) +{ + efi_status_t status; + unsigned long kernel_size = 0; + unsigned long preferred_addr; + + kernel_size = _edata - _start; + *reserve_size = kernel_size + (_end - _edata); + *image_addr = (unsigned long)_start; + + /* + * RISC-V kernel maps PAGE_OFFSET virtual address to the same physical + * address where kernel is booted. That's why kernel should boot from + * as low as possible to avoid wastage of memory. Currently, dram_base + * is occupied by the firmware. So the preferred address for kernel to + * boot is next aligned address. If preferred address is not available, + * relocate_kernel will fall back to efi_low_alloc_above to allocate + * lowest possible memory region as long as the address and size meets + * the alignment constraints. + */ + preferred_addr = round_up(dram_base, MIN_KIMG_ALIGN) + MIN_KIMG_ALIGN; + status = efi_relocate_kernel(image_addr, kernel_size, *reserve_size, + preferred_addr, MIN_KIMG_ALIGN, dram_base); + + if (status != EFI_SUCCESS) { + pr_efi_err("Failed to relocate kernel\n"); + *reserve_size = 0; + return status; + } + + return EFI_SUCCESS; +}