From patchwork Fri Aug 28 17:20:35 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Atish Patra X-Patchwork-Id: 254248 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=-12.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, 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 E77C1C433E6 for ; Fri, 28 Aug 2020 17:21:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A56E120848 for ; Fri, 28 Aug 2020 17:21:44 +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="R79LuVZh" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727793AbgH1RVl (ORCPT ); Fri, 28 Aug 2020 13:21:41 -0400 Received: from esa4.hgst.iphmx.com ([216.71.154.42]:11691 "EHLO esa4.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727066AbgH1RVQ (ORCPT ); Fri, 28 Aug 2020 13:21:16 -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=1598635275; x=1630171275; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=DZn1zX5v4AKwiAK5OKt0fHKD9YO5xGV8inFUgUfZc6I=; b=R79LuVZhInB/sEdZJzDWeqNvrJC1Nmho3PBVmT2cWVpX2QvekLBZ5KdA da141w8FmltqSYpqZ7hHV9dvfRRdKHppIelNHPePUugVFk4zHvGV6uNAu 8pxtSC1OmoSTXHWlSSsdYgxo+Q59chZE5M7BAP/Ui5S5+lBmAx0ZKWzDw bxfG0a1zq9V4wTgK0IdV6zexUAo6O7achH1MgdpTamMq/kjmon1BunpUo Rf/eNO/YdKoEBsIVb6GYvhvjuyZCL0KWZJwmhXZwKbO0YJtV8FZUH2Df8 dvxufvWzpx0dnUdZqCISzbViS7wQlDSKn1xL50shdqGCQRJI4ibMTeSqK Q==; IronPort-SDR: gMe8JV3pxIzKbry1mGLkT+L2CG4QgJ5c8M+9U85UPiaiPtLguLignchpwPAS+F9ZNGty8Gx5O3 RA0NnTnc1KpwR8nva9cdoVY+bDiilRiMF7If5kW99trpSUHna8Y+Fn+dvclmkMMV2wgrNGMOCw F8PZypYq1UqKXyKDiYUNkPjY2p6fXsXnBwbKnvJRNdhe2DPvEjczyOlUXVj3F/0wxrLsE4NXNI ZColEypgJ7lCAqzHr0FBGrxp25xK95EMCiEBfZ7CKTRYIfjGAU1WQ1uZzMv4tQW8jJd+GvgdP1 nfU= X-IronPort-AV: E=Sophos;i="5.76,364,1592841600"; d="scan'208";a="146018526" Received: from h199-255-45-14.hgst.com (HELO uls-op-cesaep01.wdc.com) ([199.255.45.14]) by ob1.hgst.iphmx.com with ESMTP; 29 Aug 2020 01:20:47 +0800 IronPort-SDR: w3331GW3kr9IRFB6jqGUG/TtijeRtrJEQ5LRUeJWpcwG2uG5SnjvnHJwXNBmB0eaEVCSkJ3lQ5 eGfcJB3Agrdw== 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; 28 Aug 2020 10:08:19 -0700 IronPort-SDR: 3Gcp4bXh/V3FkFUCmqd3iPOoTBHFAPbk/T9yPoEZ1UyYOPYvKmkzdPkCVzA96v/Ym7Fr9iGW3w Ry6Dm5m9FNrg== WDCIronportException: Internal Received: from 6hj08h2.ad.shared (HELO jedi-01.hgst.com) ([10.86.59.137]) by uls-op-cesaip01.wdc.com with ESMTP; 28 Aug 2020 10:20:46 -0700 From: Atish Patra To: linux-kernel@vger.kernel.org Cc: Atish Patra , Ard Biesheuvel , Alistair Francis , Anup Patel , Arvind Sankar , Greentime Hu , Ingo Molnar , linux-efi@vger.kernel.org, linux-riscv@lists.infradead.org, Masahiro Yamada , Mike Rapoport , Nick Desaulniers , Palmer Dabbelt , Paul Walmsley Subject: [PATCH v7 8/9] RISC-V: Add EFI runtime services Date: Fri, 28 Aug 2020 10:20:35 -0700 Message-Id: <20200828172036.8056-9-atish.patra@wdc.com> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20200828172036.8056-1-atish.patra@wdc.com> References: <20200828172036.8056-1-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 This patch adds EFI runtime service support for RISC-V. Signed-off-by: Atish Patra Acked-by: Ard Biesheuvel --- arch/riscv/Kconfig | 2 + arch/riscv/include/asm/efi.h | 20 ++++ arch/riscv/include/asm/mmu.h | 2 + arch/riscv/include/asm/pgtable.h | 4 + arch/riscv/kernel/Makefile | 1 + arch/riscv/kernel/efi.c | 105 +++++++++++++++++ arch/riscv/kernel/setup.c | 7 +- arch/riscv/mm/init.c | 2 +- drivers/firmware/efi/Makefile | 2 + drivers/firmware/efi/libstub/efi-stub.c | 11 +- drivers/firmware/efi/riscv-runtime.c | 143 ++++++++++++++++++++++++ 11 files changed, 295 insertions(+), 4 deletions(-) create mode 100644 arch/riscv/kernel/efi.c create mode 100644 drivers/firmware/efi/riscv-runtime.c diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 6ef2394be857..c8e57d77c144 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -412,7 +412,9 @@ config EFI select EFI_PARAMS_FROM_FDT select EFI_STUB select EFI_GENERIC_STUB + select EFI_RUNTIME_WRAPPERS select RISCV_ISA_C + depends on MMU default y help This option provides support for runtime services provided diff --git a/arch/riscv/include/asm/efi.h b/arch/riscv/include/asm/efi.h index 86da231909bb..93c305a638f4 100644 --- a/arch/riscv/include/asm/efi.h +++ b/arch/riscv/include/asm/efi.h @@ -5,11 +5,28 @@ #ifndef _ASM_EFI_H #define _ASM_EFI_H +#include #include #include #include #include +#ifdef CONFIG_EFI +extern void efi_init(void); +#else +#define efi_init() +#endif + +int efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md); +int efi_set_mapping_permissions(struct mm_struct *mm, efi_memory_desc_t *md); + +#define arch_efi_call_virt_setup() efi_virtmap_load() +#define arch_efi_call_virt_teardown() efi_virtmap_unload() + +#define arch_efi_call_virt(p, f, args...) p->f(args) + +#define ARCH_EFI_IRQ_FLAGS_MASK (SR_IE | SR_SPIE) + /* 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) { @@ -33,4 +50,7 @@ static inline void efifb_setup_from_dmi(struct screen_info *si, const char *opt) { } +void efi_virtmap_load(void); +void efi_virtmap_unload(void); + #endif /* _ASM_EFI_H */ diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h index 967eacb01ab5..dabcf2cfb3dc 100644 --- a/arch/riscv/include/asm/mmu.h +++ b/arch/riscv/include/asm/mmu.h @@ -20,6 +20,8 @@ typedef struct { #endif } mm_context_t; +void __init create_pgd_mapping(pgd_t *pgdp, uintptr_t va, phys_addr_t pa, + phys_addr_t sz, pgprot_t prot); #endif /* __ASSEMBLY__ */ #endif /* _ASM_RISCV_MMU_H */ diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h index 815f8c959dd4..183f1f4b2ae6 100644 --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -100,6 +100,10 @@ #define PAGE_KERNEL __pgprot(_PAGE_KERNEL) #define PAGE_KERNEL_EXEC __pgprot(_PAGE_KERNEL | _PAGE_EXEC) +#define PAGE_KERNEL_READ __pgprot(_PAGE_KERNEL & ~_PAGE_WRITE) +#define PAGE_KERNEL_EXEC __pgprot(_PAGE_KERNEL | _PAGE_EXEC) +#define PAGE_KERNEL_READ_EXEC __pgprot((_PAGE_KERNEL & ~_PAGE_WRITE) \ + | _PAGE_EXEC) #define PAGE_TABLE __pgprot(_PAGE_TABLE) diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile index 41e3895a3192..e922ffe0f39e 100644 --- a/arch/riscv/kernel/Makefile +++ b/arch/riscv/kernel/Makefile @@ -35,6 +35,7 @@ OBJCOPYFLAGS := --prefix-symbols=__efistub_ $(obj)/%.stub.o: $(obj)/%.o FORCE $(call if_changed,objcopy) +obj-$(CONFIG_EFI) += efi.o 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.c b/arch/riscv/kernel/efi.c new file mode 100644 index 000000000000..d7a723b446c3 --- /dev/null +++ b/arch/riscv/kernel/efi.c @@ -0,0 +1,105 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2020 Western Digital Corporation or its affiliates. + * Adapted from arch/arm64/kernel/efi.c + */ + +#include +#include + +#include +#include +#include + +/* + * Only regions of type EFI_RUNTIME_SERVICES_CODE need to be + * executable, everything else can be mapped with the XN bits + * set. Also take the new (optional) RO/XP bits into account. + */ +static __init pgprot_t efimem_to_pgprot_map(efi_memory_desc_t *md) +{ + u64 attr = md->attribute; + u32 type = md->type; + + if (type == EFI_MEMORY_MAPPED_IO) + return PAGE_KERNEL; + + if (WARN_ONCE(!PAGE_ALIGNED(md->phys_addr), + "UEFI Runtime regions are not aligned to page size -- buggy firmware?")) + /* + * If the region is not aligned to the page size of the OS, we + * can not use strict permissions, since that would also affect + * the mapping attributes of the adjacent regions. + */ + return PAGE_EXEC; + + /* R-- */ + if ((attr & (EFI_MEMORY_XP | EFI_MEMORY_RO)) == + (EFI_MEMORY_XP | EFI_MEMORY_RO)) + return PAGE_KERNEL_READ; + + /* R-X */ + if (attr & EFI_MEMORY_RO) + return PAGE_KERNEL_READ_EXEC; + + /* RW- */ + if (((attr & (EFI_MEMORY_RP | EFI_MEMORY_WP | EFI_MEMORY_XP)) == + EFI_MEMORY_XP) || + type != EFI_RUNTIME_SERVICES_CODE) + return PAGE_KERNEL; + + /* RWX */ + return PAGE_KERNEL_EXEC; +} + +int __init efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md) +{ + pgprot_t prot = __pgprot(pgprot_val(efimem_to_pgprot_map(md)) & + ~(_PAGE_GLOBAL)); + int i; + + /* RISC-V maps one page at a time */ + for (i = 0; i < md->num_pages; i++) + create_pgd_mapping(mm->pgd, md->virt_addr + i * PAGE_SIZE, + md->phys_addr + i * PAGE_SIZE, + PAGE_SIZE, prot); + return 0; +} + +static int __init set_permissions(pte_t *ptep, unsigned long addr, void *data) +{ + efi_memory_desc_t *md = data; + pte_t pte = READ_ONCE(*ptep); + unsigned long val; + + if (md->attribute & EFI_MEMORY_RO) { + val = pte_val(pte) & ~_PAGE_WRITE; + val = pte_val(pte) | _PAGE_READ; + pte = __pte(val); + } + if (md->attribute & EFI_MEMORY_XP) { + val = pte_val(pte) & ~_PAGE_EXEC; + pte = __pte(val); + } + set_pte(ptep, pte); + + return 0; +} + +int __init efi_set_mapping_permissions(struct mm_struct *mm, + efi_memory_desc_t *md) +{ + BUG_ON(md->type != EFI_RUNTIME_SERVICES_CODE && + md->type != EFI_RUNTIME_SERVICES_DATA); + + /* + * Calling apply_to_page_range() is only safe on regions that are + * guaranteed to be mapped down to pages. Since we are only called + * for regions that have been mapped using efi_create_mapping() above + * (and this is checked by the generic Memory Attributes table parsing + * routines), there is no need to check that again here. + */ + return apply_to_page_range(mm, md->virt_addr, + md->num_pages << EFI_PAGE_SHIFT, + set_permissions, md); +} diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c index 41ef96d0d97a..4c96ac198e14 100644 --- a/arch/riscv/kernel/setup.c +++ b/arch/riscv/kernel/setup.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include @@ -26,11 +27,12 @@ #include #include #include +#include #include "head.h" -#ifdef CONFIG_DUMMY_CONSOLE -struct screen_info screen_info = { +#if defined(CONFIG_DUMMY_CONSOLE) || defined(CONFIG_EFI) +struct screen_info screen_info __section(.data) = { .orig_video_lines = 30, .orig_video_cols = 80, .orig_video_mode = 0, @@ -75,6 +77,7 @@ void __init setup_arch(char **cmdline_p) early_ioremap_setup(); parse_early_param(); + efi_init(); setup_bootmem(); paging_init(); #if IS_ENABLED(CONFIG_BUILTIN_DTB) diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index cac2c31f8beb..32e7258da9bb 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -390,7 +390,7 @@ static void __init create_pmd_mapping(pmd_t *pmdp, #define fixmap_pgd_next fixmap_pte #endif -static void __init create_pgd_mapping(pgd_t *pgdp, +void __init create_pgd_mapping(pgd_t *pgdp, uintptr_t va, phys_addr_t pa, phys_addr_t sz, pgprot_t prot) { diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile index 61fd1e8b26fb..4d628081bb2f 100644 --- a/drivers/firmware/efi/Makefile +++ b/drivers/firmware/efi/Makefile @@ -35,6 +35,8 @@ fake_map-$(CONFIG_X86) += x86_fake_mem.o arm-obj-$(CONFIG_EFI) := efi-init.o arm-runtime.o obj-$(CONFIG_ARM) += $(arm-obj-y) obj-$(CONFIG_ARM64) += $(arm-obj-y) +riscv-obj-$(CONFIG_EFI) := efi-init.o riscv-runtime.o +obj-$(CONFIG_RISCV) += $(riscv-obj-y) obj-$(CONFIG_EFI_CAPSULE_LOADER) += capsule-loader.o obj-$(CONFIG_EFI_EARLYCON) += earlycon.o obj-$(CONFIG_UEFI_CPER_ARM) += cper-arm.o diff --git a/drivers/firmware/efi/libstub/efi-stub.c b/drivers/firmware/efi/libstub/efi-stub.c index a5a405d8ab44..5c26725d8fd0 100644 --- a/drivers/firmware/efi/libstub/efi-stub.c +++ b/drivers/firmware/efi/libstub/efi-stub.c @@ -17,7 +17,10 @@ /* * This is the base address at which to start allocating virtual memory ranges - * for UEFI Runtime Services. This is in the low TTBR0 range so that we can use + * for UEFI Runtime Services. + * + * For ARM/ARM64: + * This is in the low TTBR0 range so that we can use * any allocation we choose, and eliminate the risk of a conflict after kexec. * The value chosen is the largest non-zero power of 2 suitable for this purpose * both on 32-bit and 64-bit ARM CPUs, to maximize the likelihood that it can @@ -25,6 +28,12 @@ * Since 32-bit ARM could potentially execute with a 1G/3G user/kernel split, * map everything below 1 GB. (512 MB is a reasonable upper bound for the * entire footprint of the UEFI runtime services memory regions) + * + * For RISC-V: + * There is no specific reason for which, this address (512MB) can't be used + * EFI runtime virtual address for RISC-V. It also helps to use EFI runtime + * services on both RV32/RV64. Keep the same runtime virtual address for RISC-V + * as well to minimize the code churn. */ #define EFI_RT_VIRTUAL_BASE SZ_512M #define EFI_RT_VIRTUAL_SIZE SZ_512M diff --git a/drivers/firmware/efi/riscv-runtime.c b/drivers/firmware/efi/riscv-runtime.c new file mode 100644 index 000000000000..d28e715d2bcc --- /dev/null +++ b/drivers/firmware/efi/riscv-runtime.c @@ -0,0 +1,143 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Extensible Firmware Interface + * + * Copyright (C) 2020 Western Digital Corporation or its affiliates. + * + * Based on Extensible Firmware Interface Specification version 2.4 + * Adapted from drivers/firmware/efi/arm-runtime.c + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include + +static bool __init efi_virtmap_init(void) +{ + efi_memory_desc_t *md; + + efi_mm.pgd = pgd_alloc(&efi_mm); + mm_init_cpumask(&efi_mm); + init_new_context(NULL, &efi_mm); + + for_each_efi_memory_desc(md) { + phys_addr_t phys = md->phys_addr; + int ret; + + if (!(md->attribute & EFI_MEMORY_RUNTIME)) + continue; + if (md->virt_addr == 0) + return false; + + ret = efi_create_mapping(&efi_mm, md); + if (ret) { + pr_warn(" EFI remap %pa: failed to create mapping (%d)\n", + &phys, ret); + return false; + } + } + + if (efi_memattr_apply_permissions(&efi_mm, efi_set_mapping_permissions)) + return false; + + return true; +} + +/* + * Enable the UEFI Runtime Services if all prerequisites are in place, i.e., + * non-early mapping of the UEFI system table and virtual mappings for all + * EFI_MEMORY_RUNTIME regions. + */ +static int __init riscv_enable_runtime_services(void) +{ + u64 mapsize; + + if (!efi_enabled(EFI_BOOT)) { + pr_info("EFI services will not be available.\n"); + return 0; + } + + efi_memmap_unmap(); + + mapsize = efi.memmap.desc_size * efi.memmap.nr_map; + + if (efi_memmap_init_late(efi.memmap.phys_map, mapsize)) { + pr_err("Failed to remap EFI memory map\n"); + return 0; + } + + if (efi_soft_reserve_enabled()) { + efi_memory_desc_t *md; + + for_each_efi_memory_desc(md) { + int md_size = md->num_pages << EFI_PAGE_SHIFT; + struct resource *res; + + if (!(md->attribute & EFI_MEMORY_SP)) + continue; + + res = kzalloc(sizeof(*res), GFP_KERNEL); + if (WARN_ON(!res)) + break; + + res->start = md->phys_addr; + res->end = md->phys_addr + md_size - 1; + res->name = "Soft Reserved"; + res->flags = IORESOURCE_MEM; + res->desc = IORES_DESC_SOFT_RESERVED; + + insert_resource(&iomem_resource, res); + } + } + + if (efi_runtime_disabled()) { + pr_info("EFI runtime services will be disabled.\n"); + return 0; + } + + if (efi_enabled(EFI_RUNTIME_SERVICES)) { + pr_info("EFI runtime services access via paravirt.\n"); + return 0; + } + + pr_info("Remapping and enabling EFI services.\n"); + + if (!efi_virtmap_init()) { + pr_err("UEFI virtual mapping missing or invalid -- runtime services will not be available\n"); + return -ENOMEM; + } + + /* Set up runtime services function pointers */ + efi_native_runtime_setup(); + set_bit(EFI_RUNTIME_SERVICES, &efi.flags); + + return 0; +} +early_initcall(riscv_enable_runtime_services); + +void efi_virtmap_load(void) +{ + preempt_disable(); + switch_mm(current->active_mm, &efi_mm, NULL); +} + +void efi_virtmap_unload(void) +{ + switch_mm(&efi_mm, current->active_mm, NULL); + preempt_enable(); +}