> Will check but after MMU is turned off the pages are no matter anymore so
> should be good. With MMU off for armv8 all data accesses are Device_nGnRnE,
> all instruction fetches are cacheable, all addresses are RW, XN=1
> (Executable).
XN=0 (Executable) meant. Thought would correct not to cause any confusion.
> > > Signed-off-by: Marek Bykowski <marek.bykow...@gmail.com>
> > > ---
> > > Changes in PATCH v1:
> > > - now it re-maps the whole RAM to the proper attributes,
> > > - took account of other images, eg. PSCI, EFI that need a separate
> > > attention
> > > - it has been tested on qemu arm 64 and two of my armv8 boards, one is
> > > Axxia
> > > series of the processor, the other is so early that the name cannot be
> > > revealed yet
> > >
> > > arch/arm/cpu/armv8/cache_v8.c | 103
> > > +++++++++++++++++++++++++++++++
> > > arch/arm/cpu/armv8/u-boot.lds | 39 ++++++++++--
> > > arch/arm/include/asm/armv8/mmu.h | 6 ++
> > > arch/arm/lib/sections.c | 19 ++++--
> > > include/asm-generic/sections.h | 9 +++
> > > 5 files changed, 164 insertions(+), 12 deletions(-)
> > >
> > > diff --git a/arch/arm/cpu/armv8/cache_v8.c b/arch/arm/cpu/armv8/cache_v8.c
> > > index 7c31d98a6f..4d8843d05e 100644
> > > --- a/arch/arm/cpu/armv8/cache_v8.c
> > > +++ b/arch/arm/cpu/armv8/cache_v8.c
> > > @@ -14,6 +14,7 @@
> > > #include <asm/cache.h>
> > > #include <asm/system.h>
> > > #include <asm/armv8/mmu.h>
> > > +#include <asm/sections.h>
> > >
> > > DECLARE_GLOBAL_DATA_PTR;
> > >
> > > @@ -364,6 +365,100 @@ __weak u64 get_page_table_size(void)
> > > return size;
> > > }
> > >
> > > +__weak void force_remaping_ram(void)
> > > +{
> > > + int i = 0;
> > > +
> > > + if (!(gd->flags & GD_FLG_RELOC))
> > > + return;
> > > +
> > > + struct mm_region mem_map_ram[] = {
> > > + /*
> > > + * Re-map the whole RAM to Read-Write, Non-Executable, and
> > > + * then .text section/s to Read-Only, Executable.
> > > + */
> > > + {
> > > + .virt = (u64)gd->ram_base,
> > > + .phys = (u64)gd->ram_base,
> > > + .size = (u64)gd->ram_size,
> > > + .attrs = PTE_BLOCK_MEMTYPE(MT_NORMAL) |
> > > + PTE_BLOCK_INNER_SHARE |
> > > + PTE_BLOCK_UXN
> > > + },
> > > +#if IS_ENABLED(CONFIG_EFI_LOADER)
> > > + {
> > > + .virt = (u64)__efi_runtime_start_section,
> > > + .phys = (u64)__efi_runtime_start_section,
> > > + .size = (u64)(__efi_runtime_stop_section -
> > > + __efi_runtime_start_section),
> > > + .attrs = (PTE_BLOCK_MEMTYPE(MT_NORMAL) |
> > > + PTE_BLOCK_INNER_SHARE) &
> > > ~PTE_BLOCK_UXN
> > > + },
> > > + {
> > > + .virt = (u64)__efi_runtime_rel_start_section,
> > > + .phys = (u64)__efi_runtime_rel_start_section,
> > > + .size = (u64)(__efi_runtime_rel_stop_section -
> > > + __efi_runtime_rel_start_section),
> > > + .attrs = (PTE_BLOCK_MEMTYPE(MT_NORMAL) |
> > > + PTE_BLOCK_INNER_SHARE) &
> > > ~PTE_BLOCK_UXN
> > > + },
> > > +#endif
> > > + {
> > > + .virt = (u64)__image_copy_start,
> > > + .phys = (u64)__image_copy_start,
> > > + .size = (u64)(__text_end - __image_copy_start),
> > > + .attrs = (PTE_BLOCK_MEMTYPE(MT_NORMAL) |
> > > + PTE_BLOCK_INNER_SHARE |
> > > PTE_BLOCK_AP_RO) &
> > > + ~PTE_BLOCK_UXN
> > > + },
> > > + {
> > > + .virt = (u64)__text_rest_start,
> > > + .phys = (u64)__text_rest_start,
> > > + .size = (u64)(__text_rest_end - __text_rest_start),
> > > + .attrs = (PTE_BLOCK_MEMTYPE(MT_NORMAL) |
> > > + PTE_BLOCK_INNER_SHARE |
> > > PTE_BLOCK_AP_RO) &
> > > + ~PTE_BLOCK_UXN
> > > + },
> > > +#if IS_ENABLED(CONFIG_ARMV8_SECURE_BASE)
> > > + {
> > > + .virt = (u64)__secure_text_start,
> > > + .phys = (u64)__secure_text_start,
> > > + .size = (u64)(__secure_text_end - __secure_text_start),
> > > + .attrs = (PTE_BLOCK_MEMTYPE(MT_NORMAL) |
> > > + PTE_BLOCK_INNER_SHARE |
> > > PTE_BLOCK_AP_RO) &
> > > + ~PTE_BLOCK_UXN
> > > + },
> > > +#endif
> > > + { 0 }
> > > + };
> > > +
> > > + debug("Re-mapping RAM: Code to RO,XN=0, Data - RW,XN=1");
> > > + if (IS_ENABLED(CONFIG_EFI_LOADER) ||
> > > IS_ENABLED(CONFIG_ARMV8_SECURE_BASE))
> > > + debug(", Non-U-Boot images (eg. efi, psci) - RW,XN=0
> > > (unchanged)");
> > > + debug("\n");
> > > +
> > > + for (; mem_map_ram[i].size || mem_map_ram[i].attrs; i++) {
> > > + /*
> > > + * MT_NORMAL - Normal Memory
> > > + * MT_DEVICE_NGNRNE - Device Memory (we don't expect that
> > > + * really for the RAM to happen...)
> > > + * RO - read-only
> > > + * RW - read-write
> > > + * XN=0 - Executable
> > > + * XN=1 - Non-executable
> > > + */
> > > + debug("[%d]: 0x%llx-0x%llx %s%s%s\n",
> > > + i, mem_map_ram[i].phys, mem_map_ram[i].phys +
> > > + mem_map_ram[i].size,
> > > + mem_map_ram[i].attrs &
> > > PTE_BLOCK_MEMTYPE(MT_NORMAL) ?
> > > + "MT_NORMAL" : "MT_DEVICE",
> > > + mem_map_ram[i].attrs & PTE_BLOCK_AP_RO ? "-RO" : "-
> > > RW",
> > > + mem_map_ram[i].attrs & PTE_BLOCK_UXN ?
> > > + "-XN=1" : "-XN=0");
> > > + add_map(&mem_map_ram[i]);
> > > + }
> > > +}
> > > +
> > > void setup_pgtables(void)
> > > {
> > > int i;
> > > @@ -381,6 +476,14 @@ void setup_pgtables(void)
> > > /* Now add all MMU table entries one after another to the table */
> > > for (i = 0; mem_map[i].size || mem_map[i].attrs; i++)
> > > add_map(&mem_map[i]);
> > > +
> > > + /*
> > > + * Force re-mapping RAM only if the generic linker script in use.
> > > + * The boundaries of the regions for re-mapping are defined in
> > > + * the generic ARM64 ld script and won't work for the custom ones.
> > > + */
> > > + if (!IS_ENABLED(CONFIG_SYS_CUSTOM_LDSCRIPT))
> > > + force_remaping_ram();
> > > }
> > >
> > > static void setup_all_pgtables(void)
> > > diff --git a/arch/arm/cpu/armv8/u-boot.lds
> > > b/arch/arm/cpu/armv8/u-boot.lds index
> > > 2554980595..8e98b143d5 100644
> > > --- a/arch/arm/cpu/armv8/u-boot.lds
> > > +++ b/arch/arm/cpu/armv8/u-boot.lds
> > > @@ -9,6 +9,7 @@
> > >
> > > #include <config.h>
> > > #include <asm/psci.h>
> > > +#include <asm/armv8/mmu.h>
> > >
> > > OUTPUT_FORMAT("elf64-littleaarch64", "elf64-littleaarch64", "elf64-
> > > littleaarch64")
> > > OUTPUT_ARCH(aarch64)
> > > @@ -20,25 +21,36 @@ SECTIONS
> > > #endif
> > > . = 0x00000000;
> > >
> > > - . = ALIGN(8);
> > > + /* Align .text to the page size */
> > > + . = ALIGN(PAGE_SIZE);
> > > .text :
> > > {
> > > *(.__image_copy_start)
> > > CPUDIR/start.o (.text*)
> > > + . = ALIGN(PAGE_SIZE);
> > > + KEEP(*(.__text_end))
> > > }
> > >
> > > /* This needs to come before *(.text*) */
> > > - .efi_runtime : {
> > > - __efi_runtime_start = .;
> > > + .efi_runtime ALIGN(CONSTANT(COMMONPAGESIZE)):
> > > + {
> > > + KEEP(*(.__efi_runtime_start))
> > > + __efi_runtime_start = .;
> > > *(.text.efi_runtime*)
> > > *(.rodata.efi_runtime*)
> > > *(.data.efi_runtime*)
> > > - __efi_runtime_stop = .;
> > > + __efi_runtime_stop = .;
> > > + . = ALIGN(PAGE_SIZE);
> > > + KEEP(*(.__efi_runtime_stop))
> > > }
> > >
> > > + . = ALIGN(PAGE_SIZE);
> > > .text_rest :
> > > {
> > > + KEEP(*(.__text_rest_start))
> > > *(.text*)
> > > + . = ALIGN(PAGE_SIZE);
> > > + KEEP(*(.__text_rest_end))
> > > }
> > >
> > > #ifdef CONFIG_ARMV8_PSCI
> > > @@ -54,14 +66,18 @@ SECTIONS
> > > #define CONFIG_ARMV8_SECURE_BASE
> > > #define __ARMV8_PSCI_STACK_IN_RAM
> > > #endif
> > > + . = ALIGN(PAGE_SIZE);
> > > .secure_text CONFIG_ARMV8_SECURE_BASE :
> > > AT(ADDR(.__secure_start) + SIZEOF(.__secure_start))
> > > {
> > > + KEEP(*(.__secure_text_start))
> > > *(._secure.text)
> > > . = ALIGN(8);
> > > __secure_svc_tbl_start = .;
> > > KEEP(*(._secure_svc_tbl_entries))
> > > __secure_svc_tbl_end = .;
> > > + . = ALIGN(PAGE_SIZE);
> > > + KEEP(*(.__secure_text_end))
> > > }
> > >
> > > .secure_data : AT(LOADADDR(.secure_text) + SIZEOF(.secure_text))
> > > @@ -113,15 +129,26 @@ SECTIONS
> > > KEEP(*(SORT(.u_boot_list*)));
> > > }
> > >
> > > - . = ALIGN(8);
> > > + . = ALIGN(PAGE_SIZE);
> > > + .efi_runtime_rel_start :
> > > + {
> > > + KEEP(*(.__efi_runtime_rel_start))
> > > + }
> > >
> > > - .efi_runtime_rel : {
> > > + .efi_runtime_rel :
> > > + {
> > > __efi_runtime_rel_start = .;
> > > *(.rel*.efi_runtime)
> > > *(.rel*.efi_runtime.*)
> > > __efi_runtime_rel_stop = .;
> > > }
> > >
> > > + . = ALIGN(PAGE_SIZE);
> > > + .efi_runtime_rel_stop :
> > > + {
> > > + KEEP(*(.__efi_runtime_rel_stop))
> > > + }
> > > +
> > > . = ALIGN(8);
> > >
> > > .image_copy_end :
> > > diff --git a/arch/arm/include/asm/armv8/mmu.h
> > > b/arch/arm/include/asm/armv8/mmu.h
> > > index fc97c55114..571cc283eb 100644
> > > --- a/arch/arm/include/asm/armv8/mmu.h
> > > +++ b/arch/arm/include/asm/armv8/mmu.h
> > > @@ -59,6 +59,12 @@
> > > */
> > > #define PTE_BLOCK_MEMTYPE(x) ((x) << 2)
> > > #define PTE_BLOCK_NS (1 << 5)
> > > +/*
> > > + * AP[1] bit is ignored by hardware and is
> > > + * treated as if it was One in EL2/EL3
> > > + */
> > > +#define PTE_BLOCK_AP_RO (1 << 7)
> > > +#define PTE_BLOCK_AP_RW (0 << 7)
> > > #define PTE_BLOCK_NON_SHARE (0 << 8)
> > > #define PTE_BLOCK_OUTER_SHARE (2 << 8)
> > > #define PTE_BLOCK_INNER_SHARE (3 << 8)
> > > diff --git a/arch/arm/lib/sections.c b/arch/arm/lib/sections.c index
> > > 3bb2d8468c..b00d24843d 100644
> > > --- a/arch/arm/lib/sections.c
> > > +++ b/arch/arm/lib/sections.c
> > > @@ -3,6 +3,8 @@
> > > * Copyright 2013 Albert ARIBAUD <albert.u.b...@aribaud.net>
> > > */
> > >
> > > +#include <linux/compiler_types.h>
> > > +
> > > /**
> > > * These two symbols are declared in a C file so that the linker
> > > * uses R_ARM_RELATIVE relocation, rather than the R_ARM_ABS32 one @@ -
> > > 18,6 +20,11 @@
> > > * aliasing warnings.
> > > */
> > >
> > > +char __text_end[0] __section(".__text_end"); char __text_rest_start[0]
> > > +__section(".__text_rest_start"); char __text_rest_end[0]
> > > +__section(".__text_rest_end"); char __secure_text_start[0]
> > > +__section(".__secure_text_start");
> > > +char __secure_text_end[0] __section(".__secure_text_end");
> > > char __bss_start[0] __attribute__((section(".__bss_start")));
> > > char __bss_end[0] __attribute__((section(".__bss_end")));
> > > char __image_copy_start[0]
> > > __attribute__((section(".__image_copy_start")));
> > > @@ -26,10 +33,10 @@ char __rel_dyn_start[0]
> > > __attribute__((section(".__rel_dyn_start")));
> > > char __rel_dyn_end[0] __attribute__((section(".__rel_dyn_end")));
> > > char __secure_start[0] __attribute__((section(".__secure_start")));
> > > char __secure_end[0] __attribute__((section(".__secure_end")));
> > > -char __secure_stack_start[0]
> > > __attribute__((section(".__secure_stack_start")));
> > > -char __secure_stack_end[0]
> > > __attribute__((section(".__secure_stack_end")));
> > > -char __efi_runtime_start[0]
> > > __attribute__((section(".__efi_runtime_start")));
> > > -char __efi_runtime_stop[0]
> > > __attribute__((section(".__efi_runtime_stop")));
> > > -char __efi_runtime_rel_start[0]
> > > __attribute__((section(".__efi_runtime_rel_start")));
> > > -char __efi_runtime_rel_stop[0]
> > > __attribute__((section(".__efi_runtime_rel_stop")));
> > > +char __secure_stack_start[0] __section(".__secure_stack_start");
> > > +char __secure_stack_end[0] __section(".__secure_stack_end"); char
> > > +__efi_runtime_start_section[0] __section(".__efi_runtime_start");
> > > +char __efi_runtime_stop_section[0] __section(".__efi_runtime_stop");
> > > +char __efi_runtime_rel_start_section[0]
> > > +__section(".__efi_runtime_rel_start");
> > > +char __efi_runtime_rel_stop_section[0]
> > > +__section(".__efi_runtime_rel_stop");
> > > char _end[0] __attribute__((section(".__end")));
> > > diff --git a/include/asm-generic/sections.h
> > > b/include/asm-generic/sections.h index
> > > 0577238d60..c3dc0522ee 100644
> > > --- a/include/asm-generic/sections.h
> > > +++ b/include/asm-generic/sections.h
> > > @@ -72,6 +72,11 @@ extern void _start(void);
> > > */
> > > #ifdef CONFIG_ARM
> > >
> > > +extern char __text_end[];
> > > +extern char __text_rest_start[];
> > > +extern char __text_rest_end[];
> > > +extern char __secure_text_start[];
> > > +extern char __secure_text_end[];
> > > extern char __bss_start[];
> > > extern char __bss_end[];
> > > extern char __image_copy_start[];
> > > @@ -79,6 +84,10 @@ extern char __image_copy_end[]; extern char
> > > _image_binary_end[]; extern char __rel_dyn_start[]; extern char
> > > __rel_dyn_end[];
> > > +extern char __efi_runtime_start_section[]; extern char
> > > +__efi_runtime_stop_section[]; extern char
> > > +__efi_runtime_rel_start_section[];
> > > +extern char __efi_runtime_rel_stop_section[];
> > >
> > > #else /* don't use offsets: */
> > >
> > > --
> > > 2.21.0.896.g6a6c0f1
> >
