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From:   Atish Patra <atishp@atishpatra.org>
Date:   Fri, 16 Jul 2021 07:08:17 -0700
Message-ID: <CAOnJCU+dJtHQNn8F19senK+js_H_oj=PqaExqkWdwGY9k3nGfg@mail.gmail.com>
Subject: Re: [PATCH RFC] riscv: Remove all XIP fixups by initializing MMU in memory
To:     Alex Ghiti <alex@ghiti.fr>
Cc:     Vitaly Wool <vitaly.wool@konsulko.com>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        linux-riscv <linux-riscv@lists.infradead.org>,
        LKML <linux-kernel@vger.kernel.org>
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On Fri, Jul 16, 2021 at 6:23 AM Alex Ghiti <alex@ghiti.fr> wrote:
>
> Hi Vitaly,
>
> Le 8/07/2021 =C3=A0 16:14, Vitaly Wool a =C3=A9crit :
> > Hi Alex,
> >
> > On Thu, Jul 8, 2021 at 1:43 PM Alex Ghiti <alex@ghiti.fr> wrote:
> >>
> >> Le 18/06/2021 =C3=A0 16:23, Alexandre Ghiti a =C3=A9crit :
> >>> For XIP kernel, the variables that are accessed when the MMU is off m=
ust be
> >>> fixup and it is currently achieved by adding a preprocessor macro for=
 all
> >>> those variables. This comes with a few drawbacks:
> >>>
> >>> - it adds a lot of code, especially in mm/init.c which gets overloade=
d,
> >>> - it easily breaks XIP kernels as anyone accessing a global variable =
before
> >>>     the MMU is on must fixup this variable,
> >>> - it prevents the usage of those fixup variables anywhere outside
> >>>     mm/init.c: kernel addresses conversion macros would benefit to sw=
itch
> >>>     to inline functions.
> >>>
> >>> This patch makes the data fixups unnecessary by initializing the MMU =
in the
> >>> memory rather than in flash. Indeed, very soon in the boot process, t=
he
> >>> kernel is copied to memory and the execution continues from there unt=
il
> >>> the kernel mapping is established where the execution jumps back in
> >>> flash. Then the offsets from the PC are preserved and no fixup is
> >>> necessary. And the kernel text in memory is never reserved so it is f=
ree
> >>> to use later on.
> >>>
> >>> This solution has the following drawbacks:
> >>>
> >>> - XIP kernel boot is longer because of the copy to memory, but can be
> >>>     improved by copying only necessary parts,
> >>> - in the current implementation, it creates a hole at the beginning o=
f
> >>>     the memory which could prevent large contiguous allocation,
> >>> - it actually just inverts what needs to be fixup: now rodata and tex=
t
> >>>     symbols accessed during the initialization of the MMU must be fix=
up
> >>>     whereas it was data before. However, I found a single fixup to be
> >>>     necessary and it is the dtb physical address in case CONFIG_BUILT=
IN_DTB
> >>>     is set.
> >>>
> >>
> >> @Vitaly; Any thought about that? Could you take some time to review/te=
st
> >> this approach?
> >
> > thanks for the heads-up. In my opinion, this thing with XIP on RISC-V
> > is currently going in the completely wrong direction. I would like to
> > see less data copying and less RAM usage, not more data copying and
> > more RAM usage.
> >
>
> In this patchset, there isn't more RAM usage but indeed more data
> copying, and as said, that can be largely improved by copying only the
> necessary parts, so we should evaluate/measure the time to copy those
> parts in RAM first.
>
> > I would also like to see kernel_mapping_pa_to_va /
> > kernel_mapping_va_to_pa simplified but that is a different story. I
> > might come up with something soon though.
>
> But I did not answer your message right away as your 'disapproval' made
> me start the implementation of another idea to circumvent all those
> issues. I'll submit the RFC soon, and from there, we'll discuss which
> approach is best (because I really want to see the code cleaned in
> mm/init.c :)).
>

That would be great. The current version is very unreadable.
Thanks for working on cleaning it up.

> Alex
>
> >
> > Best regards,
> >     Vitaly
> >
> >> Thanks!
> >>
> >> Alex
> >>
> >>> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
> >>> ---
> >>>    arch/riscv/include/asm/page.h    | 12 ++---
> >>>    arch/riscv/include/asm/pgtable.h | 22 +-------
> >>>    arch/riscv/kernel/head.S         | 87 +++++++++++++++++++++++-----=
----
> >>>    arch/riscv/kernel/setup.c        |  2 +-
> >>>    arch/riscv/mm/init.c             | 59 +++-------------------
> >>>    5 files changed, 78 insertions(+), 104 deletions(-)
> >>>
> >>> diff --git a/arch/riscv/include/asm/page.h b/arch/riscv/include/asm/p=
age.h
> >>> index 5d4622a44b09..97a950bbd3bf 100644
> >>> --- a/arch/riscv/include/asm/page.h
> >>> +++ b/arch/riscv/include/asm/page.h
> >>> @@ -105,11 +105,11 @@ extern unsigned long kernel_virt_addr;
> >>>        ((x) >=3D PAGE_OFFSET && (x) < kernel_virt_addr)
> >>>
> >>>    #define linear_mapping_pa_to_va(x)  ((void *)((unsigned long)(x) +=
 va_pa_offset))
> >>> -#define kernel_mapping_pa_to_va(y)   ({                             =
                 \
> >>> -     unsigned long _y =3D y;                                        =
                   \
> >>> -     (_y >=3D CONFIG_PHYS_RAM_BASE) ?                               =
                   \
> >>> -             (void *)((unsigned long)(_y) + va_kernel_pa_offset + XI=
P_OFFSET) :      \
> >>> -             (void *)((unsigned long)(_y) + va_kernel_xip_pa_offset)=
;                \
> >>> +#define kernel_mapping_pa_to_va(y)   ({                             =
         \
> >>> +     unsigned long _y =3D y;                                        =
           \
> >>> +     (_y >=3D CONFIG_PHYS_RAM_BASE) ?                               =
           \
> >>> +             (void *)((unsigned long)(_y) + va_kernel_pa_offset) :  =
         \
> >>> +             (void *)((unsigned long)(_y) + va_kernel_xip_pa_offset)=
;        \
> >>>        })
> >>>    #define __pa_to_va_nodebug(x)               linear_mapping_pa_to_v=
a(x)
> >>>
> >>> @@ -118,7 +118,7 @@ extern unsigned long kernel_virt_addr;
> >>>        unsigned long _y =3D y;                                       =
            \
> >>>        (_y < kernel_virt_addr + XIP_OFFSET) ?                        =
          \
> >>>                ((unsigned long)(_y) - va_kernel_xip_pa_offset) :     =
          \
> >>> -             ((unsigned long)(_y) - va_kernel_pa_offset - XIP_OFFSET=
);       \
> >>> +             ((unsigned long)(_y) - va_kernel_pa_offset);           =
         \
> >>>        })
> >>>
> >>>    #define __va_to_pa_nodebug(x)       ({                            =
                  \
> >>> diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/as=
m/pgtable.h
> >>> index 3ccd2dc52e85..99ec99384bf0 100644
> >>> --- a/arch/riscv/include/asm/pgtable.h
> >>> +++ b/arch/riscv/include/asm/pgtable.h
> >>> @@ -95,17 +95,6 @@
> >>>    #include <asm/pgtable-32.h>
> >>>    #endif /* CONFIG_64BIT */
> >>>
> >>> -#ifdef CONFIG_XIP_KERNEL
> >>> -#define XIP_FIXUP(addr) ({                                          =
         \
> >>> -     uintptr_t __a =3D (uintptr_t)(addr);                           =
           \
> >>> -     (__a >=3D 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 */
> >>> -
> >>>    #ifdef CONFIG_MMU
> >>>    /* Number of entries in the page global directory */
> >>>    #define PTRS_PER_PGD    (PAGE_SIZE / sizeof(pgd_t))
> >>> @@ -683,15 +672,8 @@ static inline pmd_t pmdp_establish(struct vm_are=
a_struct *vma,
> >>>    #define kern_addr_valid(addr)   (1) /* FIXME */
> >>>
> >>>    extern char _start[];
> >>> -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 */
> >>> +extern void *dtb_early_va;
> >>> +extern uintptr_t dtb_early_pa;
> >>>
> >>>    void paging_init(void);
> >>>    void misc_mem_init(void);
> >>> diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
> >>> index 89cc58ab52b4..7ac7d2bd1a53 100644
> >>> --- a/arch/riscv/kernel/head.S
> >>> +++ b/arch/riscv/kernel/head.S
> >>> @@ -17,14 +17,33 @@
> >>>
> >>>    #ifdef CONFIG_XIP_KERNEL
> >>>    .macro XIP_FIXUP_OFFSET reg
> >>> -     REG_L t0, _xip_fixup
> >>> +     li t0, CONFIG_PHYS_RAM_BASE - CONFIG_XIP_PHYS_ADDR
> >>>        add \reg, \reg, t0
> >>>    .endm
> >>> -_xip_fixup: .dword CONFIG_PHYS_RAM_BASE - CONFIG_XIP_PHYS_ADDR - XIP=
_OFFSET
> >>> +
> >>> +.macro MEM_FIXUP_OFFSET reg
> >>> +     li t0, CONFIG_XIP_PHYS_ADDR - CONFIG_PHYS_RAM_BASE
> >>> +     add \reg, \reg, t0
> >>> +.endm
> >>> +
> >>> +.macro XIP_JUMP_TO_MEM
> >>> +     la t1, 0f
> >>> +     XIP_FIXUP_OFFSET t1
> >>> +     jalr ra, t1, 0
> >>> +0:
> >>> +     /* Reload the global pointer: we are now in memory! */
> >>> +.option push
> >>> +.option norelax
> >>> +     la gp, __global_pointer$
> >>> +.option pop
> >>> +.endm
> >>>    #else
> >>> -.macro XIP_FIXUP_OFFSET reg
> >>> +.macro MEM_FIXUP_OFFSET reg
> >>> +.endm
> >>> +
> >>> +.macro XIP_JUMP_TO_MEM
> >>>    .endm
> >>> -#endif /* CONFIG_XIP_KERNEL */
> >>> +#endif
> >>>
> >>>    __HEAD
> >>>    ENTRY(_start)
> >>> @@ -82,7 +101,6 @@ 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
> >>> @@ -105,7 +123,6 @@ 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
> >>> @@ -159,9 +176,7 @@ 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)
> >>> @@ -173,7 +188,6 @@ 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
> >>> @@ -253,14 +267,12 @@ pmp_done:
> >>>        tail .Lsecondary_park
> >>>    .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
> >>> @@ -270,17 +282,43 @@ pmp_done:
> >>>        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
> >>> +     /*
> >>> +      * Copy the kernel text and data to memory: the virtual mapping=
 will be
> >>> +      * established from there, and then we will jump back to using =
flash
> >>> +      * resident text. This avoids to fixup global symbols when the =
code
> >>> +      * is executed from flash and targets data in memory before the=
 MMU is
> >>> +      * enabled.
> >>> +      * We must preserve a0, a1 and we have no stack yet (__memcpy d=
oes not
> >>> +      * spill anything).
> >>> +      */
> >>>        mv s0, a0
> >>> -     call __copy_data
> >>> +     mv s1, a1
> >>> +
> >>> +     li a0, CONFIG_PHYS_RAM_BASE
> >>> +     la a1, _xiprom
> >>> +     la a2, _exiprom
> >>> +     sub a2, a2, a1
> >>> +     add a2, a2, 1
> >>> +     call __memcpy
> >>> +
> >>> +     li a0, CONFIG_PHYS_RAM_BASE + XIP_OFFSET
> >>> +     la a1, _sdata
> >>> +     la a2, _end
> >>> +     sub a2, a2, a1
> >>> +     add a2, a2, 1
> >>> +     call __memcpy
> >>> +
> >>> +     fence.i
> >>>
> >>> -     /* Restore a0 copy */
> >>>        mv a0, s0
> >>> -#endif
> >>> +     mv a1, s1
> >>>
> >>> -#ifndef CONFIG_XIP_KERNEL
> >>> +     /*
> >>> +      * From here, the code will be executed from memory and we'll j=
ump back
> >>> +      * to flash once the MMU is enabled.
> >>> +      */
> >>> +     XIP_JUMP_TO_MEM
> >>> +#endif
> >>>        /* Clear BSS for flat non-ELF images */
> >>>        la a3, __bss_start
> >>>        la a4, __bss_stop
> >>> @@ -290,27 +328,24 @@ 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
> >>> +     MEM_FIXUP_OFFSET a0
> >>>    #else
> >>>        mv a0, s1
> >>>    #endif /* CONFIG_BUILTIN_DTB */
> >>>        call setup_vm
> >>>    #ifdef CONFIG_MMU
> >>>        la a0, early_pg_dir
> >>> -     XIP_FIXUP_OFFSET a0
> >>>        call relocate
> >>>    #endif /* CONFIG_MMU */
> >>>
> >>> @@ -329,15 +364,19 @@ clear_bss_done:
> >>>
> >>>    .Lsecondary_start:
> >>>    #ifdef CONFIG_SMP
> >>> +     /*
> >>> +      * From here, XIP kernel will be executed from memory and we'll=
 jump back
> >>> +      * to flash once the MMU is enabled.
> >>> +      */
> >>> +     XIP_JUMP_TO_MEM
> >>> +
> >>>        /* Set trap vector to spin forever to help debug */
> >>>        la a3, .Lsecondary_park
> >>>        csrw CSR_TVEC, a3
> >>>
> >>>        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/setup.c b/arch/riscv/kernel/setup.c
> >>> index 8b7f1c791821..8b7958b30a05 100644
> >>> --- a/arch/riscv/kernel/setup.c
> >>> +++ b/arch/riscv/kernel/setup.c
> >>> @@ -279,7 +279,7 @@ 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(XIP_FIXUP(dtb_early_pa))))
> >>> +     if (early_init_dt_verify(__va(dtb_early_pa)))
> >>>                unflatten_device_tree();
> >>>        else
> >>>                pr_err("No DTB found in kernel mappings\n");
> >>> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> >>> index 3d77b04bec54..a70cdd77b2be 100644
> >>> --- a/arch/riscv/mm/init.c
> >>> +++ b/arch/riscv/mm/init.c
> >>> @@ -33,7 +33,6 @@
> >>>    unsigned long kernel_virt_addr =3D KERNEL_LINK_ADDR;
> >>>    EXPORT_SYMBOL(kernel_virt_addr);
> >>>    #ifdef CONFIG_XIP_KERNEL
> >>> -#define kernel_virt_addr       (*((unsigned long *)XIP_FIXUP(&kernel=
_virt_addr)))
> >>>    extern char _xiprom[], _exiprom[];
> >>>    #endif
> >>>
> >>> @@ -43,8 +42,8 @@ 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);
> >>> @@ -203,33 +202,18 @@ static void __init setup_bootmem(void)
> >>>    }
> >>>
> >>>    #ifdef CONFIG_MMU
> >>> -static struct pt_alloc_ops _pt_ops __initdata;
> >>> -
> >>> -#ifdef CONFIG_XIP_KERNEL
> >>> -#define pt_ops (*(struct pt_alloc_ops *)XIP_FIXUP(&_pt_ops))
> >>> -#else
> >>> -#define pt_ops _pt_ops
> >>> -#endif
> >>> +static struct pt_alloc_ops pt_ops __initdata;
> >>>
> >>>    /* Offset between linear mapping virtual address and kernel load a=
ddress */
> >>>    unsigned long va_pa_offset __ro_after_init;
> >>>    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 a=
ddress */
> >>>    #ifdef CONFIG_64BIT
> >>>    unsigned long va_kernel_pa_offset __ro_after_init;
> >>>    EXPORT_SYMBOL(va_kernel_pa_offset);
> >>>    #endif
> >>> -#ifdef CONFIG_XIP_KERNEL
> >>> -#define va_kernel_pa_offset    (*((unsigned long *)XIP_FIXUP(&va_ker=
nel_pa_offset)))
> >>> -#endif
> >>>    unsigned long va_kernel_xip_pa_offset __ro_after_init;
> >>>    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 __ro_after_init;
> >>>    EXPORT_SYMBOL(pfn_base);
> >>>
> >>> @@ -239,12 +223,6 @@ static pte_t fixmap_pte[PTRS_PER_PTE] __page_ali=
gned_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, pgpr=
ot_t prot)
> >>>    {
> >>>        unsigned long addr =3D __fix_to_virt(idx);
> >>> @@ -320,12 +298,6 @@ static pmd_t fixmap_pmd[PTRS_PER_PMD] __page_ali=
gned_bss;
> >>>    static pmd_t early_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZ=
E);
> >>>    static 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 */
> >>> @@ -442,19 +414,6 @@ 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 =3D (void *)(&_sdata);
> >>> -     void *end =3D (void *)(&_end);
> >>> -     void *to =3D (void *)CONFIG_PHYS_RAM_BASE;
> >>> -     size_t sz =3D (size_t)(end - from + 1);
> >>> -
> >>> -     memcpy(to, from, sz);
> >>> -}
> >>> -#endif
> >>> -
> >>>    #ifdef CONFIG_STRICT_KERNEL_RWX
> >>>    static __init pgprot_t pgprot_from_va(uintptr_t va)
> >>>    {
> >>> @@ -511,16 +470,10 @@ static __init pgprot_t pgprot_from_va(uintptr_t=
 va)
> >>>
> >>>    static uintptr_t load_pa __initdata;
> >>>    uintptr_t 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
> >>>    static uintptr_t xiprom __initdata;
> >>>    static uintptr_t xiprom_sz __initdata;
> >>> -#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,
> >>>                                            __always_unused bool early=
)
> >>> @@ -538,7 +491,7 @@ static void __init create_kernel_page_table(pgd_t=
 *pgdir, uintptr_t map_size,
> >>>        end_va =3D kernel_virt_addr + XIP_OFFSET + load_sz;
> >>>        for (va =3D kernel_virt_addr + XIP_OFFSET; va < end_va; va +=
=3D map_size)
> >>>                create_pgd_mapping(pgdir, va,
> >>> -                                load_pa + (va - (kernel_virt_addr + =
XIP_OFFSET)),
> >>> +                                load_pa + (va - kernel_virt_addr),
> >>>                                   map_size, PAGE_KERNEL);
> >>>    }
> >>>    #else
> >>> @@ -648,7 +601,7 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa)
> >>>         * whereas dtb_early_va will be used before setup_vm_final ins=
talls
> >>>         * the linear mapping.
> >>>         */
> >>> -     dtb_early_va =3D kernel_mapping_pa_to_va(XIP_FIXUP(dtb_pa));
> >>> +     dtb_early_va =3D kernel_mapping_pa_to_va(dtb_pa);
> >>>    #else
> >>>        dtb_early_va =3D __va(dtb_pa);
> >>>    #endif /* CONFIG_64BIT */
> >>> @@ -664,7 +617,7 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa)
> >>>        dtb_early_va =3D (void *)DTB_EARLY_BASE_VA + (dtb_pa & (PGDIR_=
SIZE - 1));
> >>>    #else /* CONFIG_BUILTIN_DTB */
> >>>    #ifdef CONFIG_64BIT
> >>> -     dtb_early_va =3D kernel_mapping_pa_to_va(XIP_FIXUP(dtb_pa));
> >>> +     dtb_early_va =3D kernel_mapping_pa_to_va(dtb_pa);
> >>>    #else
> >>>        dtb_early_va =3D __va(dtb_pa);
> >>>    #endif /* CONFIG_64BIT */
> >>>
> >
> > _______________________________________________
> > linux-riscv mailing list
> > linux-riscv@lists.infradead.org
> > http://lists.infradead.org/mailman/listinfo/linux-riscv
> >
>
> _______________________________________________
> linux-riscv mailing list
> linux-riscv@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-riscv


--=20
Regards,
Atish