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=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 64415C43461 for ; Fri, 23 Apr 2021 07:52:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2E964611C1 for ; Fri, 23 Apr 2021 07:52:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241211AbhDWHxF (ORCPT ); Fri, 23 Apr 2021 03:53:05 -0400 Received: from relay10.mail.gandi.net ([217.70.178.230]:56111 "EHLO relay10.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241147AbhDWHxC (ORCPT ); Fri, 23 Apr 2021 03:53:02 -0400 Received: from [192.168.1.12] (lfbn-lyo-1-457-219.w2-7.abo.wanadoo.fr [2.7.49.219]) (Authenticated sender: alex@ghiti.fr) by relay10.mail.gandi.net (Postfix) with ESMTPSA id 2757D24000C; Fri, 23 Apr 2021 07:52:22 +0000 (UTC) Subject: Re: [PATCH v8] RISC-V: enable XIP To: Palmer Dabbelt Cc: Paul Walmsley , aou@eecs.berkeley.edu, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, vitaly.wool@konsulko.com References: From: Alex Ghiti Message-ID: Date: Fri, 23 Apr 2021 03:52:22 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=windows-1252; format=flowed Content-Language: fr Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Palmer, Le 4/23/21 ŕ 12:22 AM, Palmer Dabbelt a écrit : > On Mon, 12 Apr 2021 23:35:14 PDT (-0700), alex@ghiti.fr wrote: >> From: Vitaly Wool >> >> Introduce XIP (eXecute In Place) support for RISC-V platforms. >> It allows code to be executed directly from non-volatile storage >> directly addressable by the CPU, such as QSPI NOR flash which can >> be found on many RISC-V platforms. This makes way for significant >> optimization of RAM footprint. The XIP kernel is not compressed >> since it has to run directly from flash, so it will occupy more >> space on the non-volatile storage. The physical flash address used >> to link the kernel object files and for storing it has to be known >> at compile time and is represented by a Kconfig option. >> >> XIP on RISC-V will for the time being only work on MMU-enabled >> kernels. >> >> Signed-off-by: Alexandre Ghiti [ Rebase on top of "Move >> kernel mapping outside the linear mapping" ] >> Signed-off-by: Vitaly Wool >> --- >>  arch/riscv/Kconfig                  |  55 +++++++++++- >>  arch/riscv/Makefile                 |   8 +- >>  arch/riscv/boot/Makefile            |  13 +++ >>  arch/riscv/include/asm/page.h       |  21 +++++ >>  arch/riscv/include/asm/pgtable.h    |  25 +++++- >>  arch/riscv/kernel/head.S            |  46 +++++++++- >>  arch/riscv/kernel/head.h            |   3 + >>  arch/riscv/kernel/setup.c           |  10 ++- >>  arch/riscv/kernel/vmlinux-xip.lds.S | 133 ++++++++++++++++++++++++++++ >>  arch/riscv/kernel/vmlinux.lds.S     |   6 ++ >>  arch/riscv/mm/init.c                | 115 ++++++++++++++++++++++-- >>  11 files changed, 418 insertions(+), 17 deletions(-) >>  create mode 100644 arch/riscv/kernel/vmlinux-xip.lds.S >> >> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig >> index 8ea60a0a19ae..7c7efdd67a10 100644 >> --- a/arch/riscv/Kconfig >> +++ b/arch/riscv/Kconfig >> @@ -28,7 +28,7 @@ config RISCV >>      select ARCH_HAS_PTE_SPECIAL >>      select ARCH_HAS_SET_DIRECT_MAP >>      select ARCH_HAS_SET_MEMORY >> -    select ARCH_HAS_STRICT_KERNEL_RWX if MMU >> +    select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL > > We now also have STRICT_MODULE_RWX, which causes a merge conflict.  I've > added both as !XIP_KERNEL, though TBH I'm not even sure thot modules > make any sense with XIP. > >>      select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST >>      select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX >>      select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT >> @@ -441,7 +441,7 @@ config EFI_STUB >> >>  config EFI >>      bool "UEFI runtime support" >> -    depends on OF >> +    depends on OF && !XIP_KERNEL >>      select LIBFDT >>      select UCS2_STRING >>      select EFI_PARAMS_FROM_FDT >> @@ -465,11 +465,60 @@ config STACKPROTECTOR_PER_TASK >>      def_bool y >>      depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS >> >> +config PHYS_RAM_BASE_FIXED >> +    bool "Explicitly specified physical RAM address" >> +    default n >> + >> +config PHYS_RAM_BASE >> +    hex "Platform Physical RAM address" >> +    depends on PHYS_RAM_BASE_FIXED >> +    default "0x80000000" >> +    help >> +      This is the physical address of RAM in the system. It has to be >> +      explicitly specified to run early relocations of read-write data >> +      from flash to RAM. >> + >> +config XIP_KERNEL >> +    bool "Kernel Execute-In-Place from ROM" >> +    depends on MMU && SPARSEMEM >> +    select PHYS_RAM_BASE_FIXED >> +    help >> +      Execute-In-Place allows the kernel to run from non-volatile >> storage >> +      directly addressable by the CPU, such as NOR flash. This saves RAM >> +      space since the text section of the kernel is not loaded from >> flash >> +      to RAM.  Read-write sections, such as the data section and stack, >> +      are still copied to RAM.  The XIP kernel is not compressed since >> +      it has to run directly from flash, so it will take more space to >> +      store it.  The flash address used to link the kernel object files, >> +      and for storing it, is configuration dependent. Therefore, if you >> +      say Y here, you must know the proper physical address where to >> +      store the kernel image depending on your own flash memory usage. >> + >> +      Also note that the make target becomes "make xipImage" rather than >> +      "make zImage" or "make Image".  The final kernel binary to put in >> +      ROM memory will be arch/riscv/boot/xipImage. >> + >> +      SPARSEMEM is required because the kernel text and rodata that are >> +      flash resident are not backed by memmap, then any attempt to get >> +      a struct page on those regions will trigger a fault. >> + >> +      If unsure, say N. >> + >> +config XIP_PHYS_ADDR >> +    hex "XIP Kernel Physical Location" >> +    depends on XIP_KERNEL >> +    default "0x21000000" >> +    help >> +      This is the physical address in your flash memory the kernel will >> +      be linked for and stored to.  This address is dependent on your >> +      own flash usage. >> + >>  endmenu >> >>  config BUILTIN_DTB >> -    def_bool n >> +    bool >>      depends on OF >> +    default y if XIP_KERNEL >> >>  menu "Power management options" >> >> diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile >> index 1368d943f1f3..8fcbec03974d 100644 >> --- a/arch/riscv/Makefile >> +++ b/arch/riscv/Makefile >> @@ -82,7 +82,11 @@ CHECKFLAGS += -D__riscv -D__riscv_xlen=$(BITS) >> >>  # Default target when executing plain make >>  boot        := arch/riscv/boot >> +ifeq ($(CONFIG_XIP_KERNEL),y) >> +KBUILD_IMAGE := $(boot)/xipImage >> +else >>  KBUILD_IMAGE    := $(boot)/Image.gz >> +endif >> >>  head-y := arch/riscv/kernel/head.o >> >> @@ -95,12 +99,14 @@ PHONY += vdso_install >>  vdso_install: >>      $(Q)$(MAKE) $(build)=arch/riscv/kernel/vdso $@ >> >> +ifneq ($(CONFIG_XIP_KERNEL),y) >>  ifeq ($(CONFIG_RISCV_M_MODE)$(CONFIG_SOC_CANAAN),yy) >>  KBUILD_IMAGE := $(boot)/loader.bin >>  else >>  KBUILD_IMAGE := $(boot)/Image.gz >>  endif >> -BOOT_TARGETS := Image Image.gz loader loader.bin >> +endif >> +BOOT_TARGETS := Image Image.gz loader loader.bin xipImage >> >>  all:    $(notdir $(KBUILD_IMAGE)) >> >> diff --git a/arch/riscv/boot/Makefile b/arch/riscv/boot/Makefile >> index 03404c84f971..6bf299f70c27 100644 >> --- a/arch/riscv/boot/Makefile >> +++ b/arch/riscv/boot/Makefile >> @@ -17,8 +17,21 @@ >>  KCOV_INSTRUMENT := n >> >>  OBJCOPYFLAGS_Image :=-O binary -R .note -R .note.gnu.build-id -R >> .comment -S >> +OBJCOPYFLAGS_xipImage :=-O binary -R .note -R .note.gnu.build-id -R >> .comment -S >> >>  targets := Image Image.* loader loader.o loader.lds loader.bin >> +targets := Image Image.* loader loader.o loader.lds loader.bin xipImage >> + >> +ifeq ($(CONFIG_XIP_KERNEL),y) >> + >> +quiet_cmd_mkxip = $(quiet_cmd_objcopy) >> +cmd_mkxip = $(cmd_objcopy) >> + >> +$(obj)/xipImage: vmlinux FORCE >> +    $(call if_changed,mkxip) >> +    @$(kecho) '  Physical Address of xipImage: $(CONFIG_XIP_PHYS_ADDR)' >> + >> +endif >> >>  $(obj)/Image: vmlinux FORCE >>      $(call if_changed,objcopy) >> diff --git a/arch/riscv/include/asm/page.h >> b/arch/riscv/include/asm/page.h >> index 22cfb2be60dc..635c6b486806 100644 >> --- a/arch/riscv/include/asm/page.h >> +++ b/arch/riscv/include/asm/page.h >> @@ -91,6 +91,9 @@ typedef struct page *pgtable_t; >>  #ifdef CONFIG_MMU >>  extern unsigned long va_pa_offset; >>  extern unsigned long va_kernel_pa_offset; >> +#ifdef CONFIG_XIP_KERNEL >> +extern unsigned long va_kernel_xip_pa_offset; >> +#endif >>  extern unsigned long pfn_base; >>  #define ARCH_PFN_OFFSET        (pfn_base) >>  #else >> @@ -102,11 +105,29 @@ extern unsigned long pfn_base; >>  extern unsigned long kernel_virt_addr; >> >>  #define linear_mapping_pa_to_va(x)    ((void *)((unsigned long)(x) + >> va_pa_offset)) >> +#ifdef CONFIG_XIP_KERNEL >> +#define kernel_mapping_pa_to_va(y)    ({                        \ >> +    unsigned long _y = y;                                \ >> +    (_y >= CONFIG_PHYS_RAM_BASE) ?                            \ >> +        (void *)((unsigned long)(_y) + va_kernel_pa_offset + >> XIP_OFFSET) :    \ >> +        (void *)((unsigned long)(_y) + >> va_kernel_xip_pa_offset);        \ >> +    }) >> +#else >>  #define kernel_mapping_pa_to_va(x)    ((void *)((unsigned long)(x) + >> va_kernel_pa_offset)) >> +#endif >>  #define __pa_to_va_nodebug(x)        linear_mapping_pa_to_va(x) >> >>  #define linear_mapping_va_to_pa(x)    ((unsigned long)(x) - >> va_pa_offset) >> +#ifdef CONFIG_XIP_KERNEL >> +#define kernel_mapping_va_to_pa(y) ({                        \ >> +    unsigned long _y = y;                            \ >> +    (_y < kernel_virt_addr + XIP_OFFSET) ?                    \ >> +        ((unsigned long)(_y) - va_kernel_xip_pa_offset) :        \ >> +        ((unsigned long)(_y) - va_kernel_pa_offset - XIP_OFFSET);    \ >> +    }) >> +#else >>  #define kernel_mapping_va_to_pa(x)    ((unsigned long)(x) - >> va_kernel_pa_offset) >> +#endif >>  #define __va_to_pa_nodebug(x)    ({                        \ >>      unsigned long _x = x;                            \ >>      (_x < kernel_virt_addr) ?                        \ >> diff --git a/arch/riscv/include/asm/pgtable.h >> b/arch/riscv/include/asm/pgtable.h >> index 80e63a93e903..c2dc4f83eed8 100644 >> --- a/arch/riscv/include/asm/pgtable.h >> +++ b/arch/riscv/include/asm/pgtable.h >> @@ -64,6 +64,19 @@ >>  #define FIXADDR_SIZE     PGDIR_SIZE >>  #endif >>  #define FIXADDR_START    (FIXADDR_TOP - FIXADDR_SIZE) >> + >> +#ifdef CONFIG_XIP_KERNEL >> +#define XIP_OFFSET        SZ_8M >> +#define XIP_FIXUP(addr) ({                            \ >> +    uintptr_t __a = (uintptr_t)(addr);                    \ >> +    (__a >= CONFIG_XIP_PHYS_ADDR && __a < CONFIG_XIP_PHYS_ADDR + >> SZ_16M) ?    \ >> +        __a - CONFIG_XIP_PHYS_ADDR + CONFIG_PHYS_RAM_BASE - >> XIP_OFFSET :\ >> +        __a;                                \ >> +    }) >> +#else >> +#define XIP_FIXUP(addr)        (addr) >> +#endif /* CONFIG_XIP_KERNEL */ >> + >>  #endif >> >>  #ifndef __ASSEMBLY__ >> @@ -499,8 +512,16 @@ static inline int ptep_clear_flush_young(struct >> vm_area_struct *vma, >>  #define kern_addr_valid(addr)   (1) /* FIXME */ >> >>  extern char _start[]; >> -extern void *dtb_early_va; >> -extern uintptr_t dtb_early_pa; >> +extern void *_dtb_early_va; >> +extern uintptr_t _dtb_early_pa; >> +#if defined(CONFIG_XIP_KERNEL) && defined(CONFIG_MMU) >> +#define dtb_early_va    (*(void **)XIP_FIXUP(&_dtb_early_va)) >> +#define dtb_early_pa    (*(uintptr_t *)XIP_FIXUP(&_dtb_early_pa)) >> +#else >> +#define dtb_early_va    _dtb_early_va >> +#define dtb_early_pa    _dtb_early_pa >> +#endif /* CONFIG_XIP_KERNEL */ >> + >>  void setup_bootmem(void); >>  void paging_init(void); >>  void misc_mem_init(void); >> diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S >> index 6cb05f22e52a..89cc58ab52b4 100644 >> --- a/arch/riscv/kernel/head.S >> +++ b/arch/riscv/kernel/head.S >> @@ -9,11 +9,23 @@ >>  #include >>  #include >>  #include >> +#include >>  #include >>  #include >>  #include >>  #include "efi-header.S" >> >> +#ifdef CONFIG_XIP_KERNEL >> +.macro XIP_FIXUP_OFFSET reg >> +    REG_L t0, _xip_fixup >> +    add \reg, \reg, t0 >> +.endm >> +_xip_fixup: .dword CONFIG_PHYS_RAM_BASE - CONFIG_XIP_PHYS_ADDR - >> XIP_OFFSET >> +#else >> +.macro XIP_FIXUP_OFFSET reg >> +.endm >> +#endif /* CONFIG_XIP_KERNEL */ >> + >>  __HEAD >>  ENTRY(_start) >>      /* >> @@ -70,6 +82,7 @@ pe_head_start: >>  relocate: >>      /* Relocate return address */ >>      la a1, kernel_virt_addr >> +    XIP_FIXUP_OFFSET a1 >>      REG_L a1, 0(a1) >>      la a2, _start >>      sub a1, a1, a2 >> @@ -92,6 +105,7 @@ relocate: >>       * to ensure the new translations are in use. >>       */ >>      la a0, trampoline_pg_dir >> +    XIP_FIXUP_OFFSET a0 >>      srl a0, a0, PAGE_SHIFT >>      or a0, a0, a1 >>      sfence.vma >> @@ -145,7 +159,9 @@ secondary_start_sbi: >> >>      slli a3, a0, LGREG >>      la a4, __cpu_up_stack_pointer >> +    XIP_FIXUP_OFFSET a4 >>      la a5, __cpu_up_task_pointer >> +    XIP_FIXUP_OFFSET a5 >>      add a4, a3, a4 >>      add a5, a3, a5 >>      REG_L sp, (a4) >> @@ -157,6 +173,7 @@ secondary_start_common: >>  #ifdef CONFIG_MMU >>      /* Enable virtual memory and relocate to virtual address */ >>      la a0, swapper_pg_dir >> +    XIP_FIXUP_OFFSET a0 >>      call relocate >>  #endif >>      call setup_trap_vector >> @@ -237,12 +254,33 @@ pmp_done: >>  .Lgood_cores: >>  #endif >> >> +#ifndef CONFIG_XIP_KERNEL >>      /* Pick one hart to run the main boot sequence */ >>      la a3, hart_lottery >>      li a2, 1 >>      amoadd.w a3, a2, (a3) >>      bnez a3, .Lsecondary_start >> >> +#else >> +    /* hart_lottery in flash contains a magic number */ >> +    la a3, hart_lottery >> +    mv a2, a3 >> +    XIP_FIXUP_OFFSET a2 >> +    lw t1, (a3) >> +    amoswap.w t0, t1, (a2) >> +    /* first time here if hart_lottery in RAM is not set */ >> +    beq t0, t1, .Lsecondary_start >> + >> +    la sp, _end + THREAD_SIZE >> +    XIP_FIXUP_OFFSET sp >> +    mv s0, a0 >> +    call __copy_data >> + >> +    /* Restore a0 copy */ >> +    mv a0, s0 >> +#endif >> + >> +#ifndef CONFIG_XIP_KERNEL >>      /* Clear BSS for flat non-ELF images */ >>      la a3, __bss_start >>      la a4, __bss_stop >> @@ -252,15 +290,18 @@ clear_bss: >>      add a3, a3, RISCV_SZPTR >>      blt a3, a4, clear_bss >>  clear_bss_done: >> - >> +#endif >>      /* Save hart ID and DTB physical address */ >>      mv s0, a0 >>      mv s1, a1 >> + >>      la a2, boot_cpu_hartid >> +    XIP_FIXUP_OFFSET a2 >>      REG_S a0, (a2) >> >>      /* Initialize page tables and relocate to virtual addresses */ >>      la sp, init_thread_union + THREAD_SIZE >> +    XIP_FIXUP_OFFSET sp >>  #ifdef CONFIG_BUILTIN_DTB >>      la a0, __dtb_start >>  #else >> @@ -269,6 +310,7 @@ clear_bss_done: >>      call setup_vm >>  #ifdef CONFIG_MMU >>      la a0, early_pg_dir >> +    XIP_FIXUP_OFFSET a0 >>      call relocate >>  #endif /* CONFIG_MMU */ >> >> @@ -293,7 +335,9 @@ clear_bss_done: >> >>      slli a3, a0, LGREG >>      la a1, __cpu_up_stack_pointer >> +    XIP_FIXUP_OFFSET a1 >>      la a2, __cpu_up_task_pointer >> +    XIP_FIXUP_OFFSET a2 >>      add a1, a3, a1 >>      add a2, a3, a2 >> >> diff --git a/arch/riscv/kernel/head.h b/arch/riscv/kernel/head.h >> index b48dda3d04f6..aabbc3ac3e48 100644 >> --- a/arch/riscv/kernel/head.h >> +++ b/arch/riscv/kernel/head.h >> @@ -12,6 +12,9 @@ extern atomic_t hart_lottery; >> >>  asmlinkage void do_page_fault(struct pt_regs *regs); >>  asmlinkage void __init setup_vm(uintptr_t dtb_pa); >> +#ifdef CONFIG_XIP_KERNEL >> +asmlinkage void __init __copy_data(void); >> +#endif >> >>  extern void *__cpu_up_stack_pointer[]; >>  extern void *__cpu_up_task_pointer[]; >> diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c >> index 30e4af0fd50c..2ddf654c72bb 100644 >> --- a/arch/riscv/kernel/setup.c >> +++ b/arch/riscv/kernel/setup.c >> @@ -50,7 +50,11 @@ struct screen_info screen_info __section(".data") = { >>   * This is used before the kernel initializes the BSS so it can't be >> in the >>   * BSS. >>   */ >> -atomic_t hart_lottery __section(".sdata"); >> +atomic_t hart_lottery __section(".sdata") >> +#ifdef CONFIG_XIP_KERNEL >> += ATOMIC_INIT(0xC001BEEF) >> +#endif >> +; >>  unsigned long boot_cpu_hartid; >>  static DEFINE_PER_CPU(struct cpu, cpu_devices); >> >> @@ -254,7 +258,7 @@ void __init setup_arch(char **cmdline_p) >>  #if IS_ENABLED(CONFIG_BUILTIN_DTB) >>      unflatten_and_copy_device_tree(); >>  #else >> -    if (early_init_dt_verify(__va(dtb_early_pa))) >> +    if (early_init_dt_verify(__va(XIP_FIXUP(dtb_early_pa)))) >>          unflatten_device_tree(); >>      else >>          pr_err("No DTB found in kernel mappings\n"); >> @@ -266,7 +270,7 @@ void __init setup_arch(char **cmdline_p) >>      if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) >>          protect_kernel_text_data(); >> >> -#if defined(CONFIG_64BIT) && defined(CONFIG_MMU) >> +#if defined(CONFIG_64BIT) && defined(CONFIG_MMU) && >> !defined(CONFIG_XIP_KERNEL) >>      protect_kernel_linear_mapping_text_rodata(); >>  #endif > > My tree doesn't look quite like this. Yes, this is because you have the patch "riscv: Protect kernel linear mapping only if CONFIG_STRICT_KERNEL_RWX is set". > Not sure if I just got the wrong > version of something, but I didn't have the CONFIG_MMU check.  It turns > out that, as I was merging this in, I saw that failing allnoconfig > (which is !MMU).  I went ahead and squashed in > > diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c > index ab394d173cd4..3e7930869ee7 100644 > --- a/arch/riscv/kernel/setup.c > +++ b/arch/riscv/kernel/setup.c > @@ -266,7 +266,7 @@ void __init setup_arch(char **cmdline_p) > >     if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) { >         protect_kernel_text_data(); > -#ifdef CONFIG_64BIT > +#if defined(CONFIG_64BIT) && defined(CONFIG_MMU) You did the right thing here, I thought the MMU check was not necessary since STRICT_KERNEL_RWX depends on MMU but the check is done at runtime...My bad. >         protect_kernel_linear_mapping_text_rodata(); > #endif >     } > > to your memory map rearrangement patch, but I'm a bit worried that I > managed to > miss something in the process. I gave it a try and it works as expected on for-next. Thanks, Alex > >> >> diff --git a/arch/riscv/kernel/vmlinux-xip.lds.S >> b/arch/riscv/kernel/vmlinux-xip.lds.S >> new file mode 100644 >> index 000000000000..4b29b9917f99 >> --- /dev/null >> +++ b/arch/riscv/kernel/vmlinux-xip.lds.S >> @@ -0,0 +1,133 @@ >> +/* SPDX-License-Identifier: GPL-2.0-only */ >> +/* >> + * Copyright (C) 2012 Regents of the University of California >> + * Copyright (C) 2017 SiFive >> + * Copyright (C) 2020 Vitaly Wool, Konsulko AB >> + */ >> + >> +#include >> +#define LOAD_OFFSET KERNEL_LINK_ADDR >> +/* No __ro_after_init data in the .rodata section - which will always >> be ro */ >> +#define RO_AFTER_INIT_DATA >> + >> +#include >> +#include >> +#include >> +#include >> +#include >> + >> +OUTPUT_ARCH(riscv) >> +ENTRY(_start) >> + >> +jiffies = jiffies_64; >> + >> +SECTIONS >> +{ >> +    /* Beginning of code and text segment */ >> +    . = LOAD_OFFSET; >> +    _xiprom = .; >> +    _start = .; >> +    HEAD_TEXT_SECTION >> +    INIT_TEXT_SECTION(PAGE_SIZE) >> +    /* we have to discard exit text and such at runtime, not link >> time */ >> +    .exit.text : >> +    { >> +        EXIT_TEXT >> +    } >> + >> +    .text : { >> +        _text = .; >> +        _stext = .; >> +        TEXT_TEXT >> +        SCHED_TEXT >> +        CPUIDLE_TEXT >> +        LOCK_TEXT >> +        KPROBES_TEXT >> +        ENTRY_TEXT >> +        IRQENTRY_TEXT >> +        SOFTIRQENTRY_TEXT >> +        *(.fixup) >> +        _etext = .; >> +    } >> +    RO_DATA(L1_CACHE_BYTES) >> +    .srodata : { >> +        *(.srodata*) >> +    } >> +    .init.rodata : { >> +        INIT_SETUP(16) >> +        INIT_CALLS >> +        CON_INITCALL >> +        INIT_RAM_FS >> +    } >> +    _exiprom = .;            /* End of XIP ROM area */ >> + >> + >> +/* >> + * From this point, stuff is considered writable and will be copied >> to RAM >> + */ >> +    __data_loc = ALIGN(16);        /* location in file */ >> +    . = LOAD_OFFSET + XIP_OFFSET;    /* location in memory */ >> + >> +    _sdata = .;            /* Start of data section */ >> +    _data = .; >> +    RW_DATA(L1_CACHE_BYTES, PAGE_SIZE, THREAD_SIZE) >> +    _edata = .; >> +    __start_ro_after_init = .; >> +    .data.ro_after_init : AT(ADDR(.data.ro_after_init) - LOAD_OFFSET) { >> +        *(.data..ro_after_init) >> +    } >> +    __end_ro_after_init = .; >> + >> +    . = ALIGN(PAGE_SIZE); >> +    __init_begin = .; >> +    .init.data : { >> +        INIT_DATA >> +    } >> +    .exit.data : { >> +        EXIT_DATA >> +    } >> +    . = ALIGN(8); >> +    __soc_early_init_table : { >> +        __soc_early_init_table_start = .; >> +        KEEP(*(__soc_early_init_table)) >> +        __soc_early_init_table_end = .; >> +    } >> +    __soc_builtin_dtb_table : { >> +        __soc_builtin_dtb_table_start = .; >> +        KEEP(*(__soc_builtin_dtb_table)) >> +        __soc_builtin_dtb_table_end = .; >> +    } >> +    PERCPU_SECTION(L1_CACHE_BYTES) >> + >> +    . = ALIGN(PAGE_SIZE); >> +    __init_end = .; >> + >> +    .sdata : { >> +        __global_pointer$ = . + 0x800; >> +        *(.sdata*) >> +        *(.sbss*) >> +    } >> + >> +    BSS_SECTION(PAGE_SIZE, PAGE_SIZE, 0) >> +    EXCEPTION_TABLE(0x10) >> + >> +    .rel.dyn : AT(ADDR(.rel.dyn) - LOAD_OFFSET) { >> +        *(.rel.dyn*) >> +    } >> + >> +    /* >> +     * End of copied data. We need a dummy section to get its LMA. >> +     * Also located before final ALIGN() as trailing padding is not >> stored >> +     * in the resulting binary file and useless to copy. >> +     */ >> +    .data.endmark : AT(ADDR(.data.endmark) - LOAD_OFFSET) { } >> +    _edata_loc = LOADADDR(.data.endmark); >> + >> +    . = ALIGN(PAGE_SIZE); >> +    _end = .; >> + >> +    STABS_DEBUG >> +    DWARF_DEBUG >> + >> +    DISCARDS >> +} >> diff --git a/arch/riscv/kernel/vmlinux.lds.S >> b/arch/riscv/kernel/vmlinux.lds.S >> index 0726c05e0336..0a59b65cf789 100644 >> --- a/arch/riscv/kernel/vmlinux.lds.S >> +++ b/arch/riscv/kernel/vmlinux.lds.S >> @@ -4,8 +4,13 @@ >>   * Copyright (C) 2017 SiFive >>   */ >> >> +#ifdef CONFIG_XIP_KERNEL >> +#include "vmlinux-xip.lds.S" >> +#else >> + >>  #include >>  #define LOAD_OFFSET KERNEL_LINK_ADDR >> + >>  #include >>  #include >>  #include >> @@ -133,3 +138,4 @@ SECTIONS >> >>      DISCARDS >>  } >> +#endif /* CONFIG_XIP_KERNEL */ >> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c >> index 093f3a96ecfc..d03e5e43d2d0 100644 >> --- a/arch/riscv/mm/init.c >> +++ b/arch/riscv/mm/init.c >> @@ -27,6 +27,9 @@ >> >>  unsigned long kernel_virt_addr = KERNEL_LINK_ADDR; >>  EXPORT_SYMBOL(kernel_virt_addr); >> +#ifdef CONFIG_XIP_KERNEL >> +#define kernel_virt_addr       (*((unsigned long >> *)XIP_FIXUP(&kernel_virt_addr))) >> +#endif >> >>  unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] >>                              __page_aligned_bss; >> @@ -34,8 +37,8 @@ EXPORT_SYMBOL(empty_zero_page); >> >>  extern char _start[]; >>  #define DTB_EARLY_BASE_VA      PGDIR_SIZE >> -void *dtb_early_va __initdata; >> -uintptr_t dtb_early_pa __initdata; >> +void *_dtb_early_va __initdata; >> +uintptr_t _dtb_early_pa __initdata; >> >>  struct pt_alloc_ops { >>      pte_t *(*get_pte_virt)(phys_addr_t pa); >> @@ -118,6 +121,10 @@ void __init setup_bootmem(void) >>      phys_addr_t dram_end = memblock_end_of_DRAM(); >>      phys_addr_t max_mapped_addr = __pa(~(ulong)0); >> >> +#ifdef CONFIG_XIP_KERNEL >> +    vmlinux_start = __pa_symbol(&_sdata); >> +#endif >> + >>      /* The maximal physical memory size is -PAGE_OFFSET. */ >>      memblock_enforce_memory_limit(-PAGE_OFFSET); >> >> @@ -159,15 +166,39 @@ void __init setup_bootmem(void) >>      memblock_allow_resize(); >>  } >> >> +#ifdef CONFIG_XIP_KERNEL >> + >> +extern char _xiprom[], _exiprom[]; >> +extern char _sdata[], _edata[]; >> + >> +#endif /* CONFIG_XIP_KERNEL */ >> + >>  #ifdef CONFIG_MMU >> -static struct pt_alloc_ops pt_ops; >> +static struct pt_alloc_ops _pt_ops; >> + >> +#ifdef CONFIG_XIP_KERNEL >> +#define pt_ops (*(struct pt_alloc_ops *)XIP_FIXUP(&_pt_ops)) >> +#else >> +#define pt_ops _pt_ops >> +#endif >> >>  /* Offset between linear mapping virtual address and kernel load >> address */ >>  unsigned long va_pa_offset; >>  EXPORT_SYMBOL(va_pa_offset); >> +#ifdef CONFIG_XIP_KERNEL >> +#define va_pa_offset   (*((unsigned long *)XIP_FIXUP(&va_pa_offset))) >> +#endif >>  /* Offset between kernel mapping virtual address and kernel load >> address */ >>  unsigned long va_kernel_pa_offset; >>  EXPORT_SYMBOL(va_kernel_pa_offset); >> +#ifdef CONFIG_XIP_KERNEL >> +#define va_kernel_pa_offset    (*((unsigned long >> *)XIP_FIXUP(&va_kernel_pa_offset))) >> +#endif >> +unsigned long va_kernel_xip_pa_offset; >> +EXPORT_SYMBOL(va_kernel_xip_pa_offset); >> +#ifdef CONFIG_XIP_KERNEL >> +#define va_kernel_xip_pa_offset        (*((unsigned long >> *)XIP_FIXUP(&va_kernel_xip_pa_offset))) >> +#endif >>  unsigned long pfn_base; >>  EXPORT_SYMBOL(pfn_base); >> >> @@ -177,6 +208,12 @@ pte_t fixmap_pte[PTRS_PER_PTE] __page_aligned_bss; >> >>  pgd_t early_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE); >> >> +#ifdef CONFIG_XIP_KERNEL >> +#define trampoline_pg_dir      ((pgd_t *)XIP_FIXUP(trampoline_pg_dir)) >> +#define fixmap_pte             ((pte_t *)XIP_FIXUP(fixmap_pte)) >> +#define early_pg_dir           ((pgd_t *)XIP_FIXUP(early_pg_dir)) >> +#endif /* CONFIG_XIP_KERNEL */ >> + >>  void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, >> pgprot_t prot) >>  { >>      unsigned long addr = __fix_to_virt(idx); >> @@ -252,6 +289,12 @@ pmd_t fixmap_pmd[PTRS_PER_PMD] __page_aligned_bss; >>  pmd_t early_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE); >>  pmd_t early_dtb_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE); >> >> +#ifdef CONFIG_XIP_KERNEL >> +#define trampoline_pmd ((pmd_t *)XIP_FIXUP(trampoline_pmd)) >> +#define fixmap_pmd     ((pmd_t *)XIP_FIXUP(fixmap_pmd)) >> +#define early_pmd      ((pmd_t *)XIP_FIXUP(early_pmd)) >> +#endif /* CONFIG_XIP_KERNEL */ >> + >>  static pmd_t *__init get_pmd_virt_early(phys_addr_t pa) >>  { >>      /* Before MMU is enabled */ >> @@ -368,6 +411,19 @@ static uintptr_t __init best_map_size(phys_addr_t >> base, phys_addr_t size) >>      return PMD_SIZE; >>  } >> >> +#ifdef CONFIG_XIP_KERNEL >> +/* called from head.S with MMU off */ >> +asmlinkage void __init __copy_data(void) >> +{ >> +    void *from = (void *)(&_sdata); >> +    void *end = (void *)(&_end); >> +    void *to = (void *)CONFIG_PHYS_RAM_BASE; >> +    size_t sz = (size_t)(end - from + 1); >> + >> +    memcpy(to, from, sz); >> +} >> +#endif >> + >>  /* >>   * setup_vm() is called from head.S with MMU-off. >>   * >> @@ -387,7 +443,35 @@ static uintptr_t __init best_map_size(phys_addr_t >> base, phys_addr_t size) >>  #endif >> >>  uintptr_t load_pa, load_sz; >> +#ifdef CONFIG_XIP_KERNEL >> +#define load_pa        (*((uintptr_t *)XIP_FIXUP(&load_pa))) >> +#define load_sz        (*((uintptr_t *)XIP_FIXUP(&load_sz))) >> +#endif >> + >> +#ifdef CONFIG_XIP_KERNEL >> +uintptr_t xiprom, xiprom_sz; >> +#define xiprom_sz      (*((uintptr_t *)XIP_FIXUP(&xiprom_sz))) >> +#define xiprom         (*((uintptr_t *)XIP_FIXUP(&xiprom))) >> >> +static void __init create_kernel_page_table(pgd_t *pgdir, uintptr_t >> map_size) >> +{ >> +    uintptr_t va, end_va; >> + >> +    /* Map the flash resident part */ >> +    end_va = kernel_virt_addr + xiprom_sz; >> +    for (va = kernel_virt_addr; va < end_va; va += map_size) >> +        create_pgd_mapping(pgdir, va, >> +                   xiprom + (va - kernel_virt_addr), >> +                   map_size, PAGE_KERNEL_EXEC); >> + >> +    /* Map the data in RAM */ >> +    end_va = kernel_virt_addr + XIP_OFFSET + load_sz; >> +    for (va = kernel_virt_addr + XIP_OFFSET; va < end_va; va += >> map_size) >> +        create_pgd_mapping(pgdir, va, >> +                   load_pa + (va - (kernel_virt_addr + XIP_OFFSET)), >> +                   map_size, PAGE_KERNEL); >> +} >> +#else >>  static void __init create_kernel_page_table(pgd_t *pgdir, uintptr_t >> map_size) >>  { >>      uintptr_t va, end_va; >> @@ -398,16 +482,28 @@ static void __init >> create_kernel_page_table(pgd_t *pgdir, uintptr_t map_size) >>                     load_pa + (va - kernel_virt_addr), >>                     map_size, PAGE_KERNEL_EXEC); >>  } >> +#endif >> >>  asmlinkage void __init setup_vm(uintptr_t dtb_pa) >>  { >> -    uintptr_t pa; >> +    uintptr_t __maybe_unused pa; >>      uintptr_t map_size; >>  #ifndef __PAGETABLE_PMD_FOLDED >>      pmd_t fix_bmap_spmd, fix_bmap_epmd; >>  #endif >> + >> +#ifdef CONFIG_XIP_KERNEL >> +    xiprom = (uintptr_t)CONFIG_XIP_PHYS_ADDR; >> +    xiprom_sz = (uintptr_t)(&_exiprom) - (uintptr_t)(&_xiprom); >> + >> +    load_pa = (uintptr_t)CONFIG_PHYS_RAM_BASE; >> +    load_sz = (uintptr_t)(&_end) - (uintptr_t)(&_sdata); >> + >> +    va_kernel_xip_pa_offset = kernel_virt_addr - xiprom; >> +#else >>      load_pa = (uintptr_t)(&_start); >>      load_sz = (uintptr_t)(&_end) - load_pa; >> +#endif >> >>      va_pa_offset = PAGE_OFFSET - load_pa; >>      va_kernel_pa_offset = kernel_virt_addr - load_pa; >> @@ -441,8 +537,13 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa) >>      /* Setup trampoline PGD and PMD */ >>      create_pgd_mapping(trampoline_pg_dir, kernel_virt_addr, >>                 (uintptr_t)trampoline_pmd, PGDIR_SIZE, PAGE_TABLE); >> +#ifdef CONFIG_XIP_KERNEL >> +    create_pmd_mapping(trampoline_pmd, kernel_virt_addr, >> +               xiprom, PMD_SIZE, PAGE_KERNEL_EXEC); >> +#else >>      create_pmd_mapping(trampoline_pmd, kernel_virt_addr, >>                 load_pa, PMD_SIZE, PAGE_KERNEL_EXEC); >> +#endif >>  #else >>      /* Setup trampoline PGD */ >>      create_pgd_mapping(trampoline_pg_dir, kernel_virt_addr, >> @@ -474,7 +575,7 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa) >>       * whereas dtb_early_va will be used before setup_vm_final installs >>       * the linear mapping. >>       */ >> -    dtb_early_va = kernel_mapping_pa_to_va(dtb_pa); >> +    dtb_early_va = kernel_mapping_pa_to_va(XIP_FIXUP(dtb_pa)); >>  #endif /* CONFIG_BUILTIN_DTB */ >>  #else >>  #ifndef CONFIG_BUILTIN_DTB >> @@ -486,7 +587,7 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa) >>                 pa + PGDIR_SIZE, PGDIR_SIZE, PAGE_KERNEL); >>      dtb_early_va = (void *)DTB_EARLY_BASE_VA + (dtb_pa & (PGDIR_SIZE >> - 1)); >>  #else /* CONFIG_BUILTIN_DTB */ >> -    dtb_early_va = kernel_mapping_pa_to_va(dtb_pa); >> +    dtb_early_va = kernel_mapping_pa_to_va(XIP_FIXUP(dtb_pa)); >>  #endif /* CONFIG_BUILTIN_DTB */ >>  #endif >>      dtb_early_pa = dtb_pa; >> @@ -522,7 +623,7 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa) >>  #endif >>  } >> >> -#ifdef CONFIG_64BIT >> +#if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL) >>  void protect_kernel_linear_mapping_text_rodata(void) >>  { >>      unsigned long text_start = (unsigned long)lm_alias(_start); > > _______________________________________________ > linux-riscv mailing list > linux-riscv@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-riscv