efi: stub: get rid of efi_get_max_fdt_addr()

Now that ARM started following the example of arm64 and RISC-V, and
no longer imposes any restrictions on the placement of the FDT in
memory at boot, we no longer need per-arch implementations of
efi_get_max_fdt_addr() to factor out the differences. So get rid of
it.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 arch/arm/include/asm/efi.h              | 6 ------
 arch/arm64/include/asm/efi.h            | 6 ------
 arch/riscv/include/asm/efi.h            | 6 ------
 drivers/firmware/efi/libstub/efi-stub.c | 1 -
 drivers/firmware/efi/libstub/efistub.h  | 1 -
 drivers/firmware/efi/libstub/fdt.c      | 3 +--
 6 files changed, 1 insertion(+), 22 deletions(-)

On Thu, Oct 29, 2020 at 6:49 AM Ard Biesheuvel <ardb@kernel.org> wrote:
>
> Now that ARM started following the example of arm64 and RISC-V, and
> no longer imposes any restrictions on the placement of the FDT in
> memory at boot, we no longer need per-arch implementations of
> efi_get_max_fdt_addr() to factor out the differences. So get rid of
> it.
>
> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
> ---
>  arch/arm/include/asm/efi.h              | 6 ------
>  arch/arm64/include/asm/efi.h            | 6 ------
>  arch/riscv/include/asm/efi.h            | 6 ------
>  drivers/firmware/efi/libstub/efi-stub.c | 1 -
>  drivers/firmware/efi/libstub/efistub.h  | 1 -
>  drivers/firmware/efi/libstub/fdt.c      | 3 +--
>  6 files changed, 1 insertion(+), 22 deletions(-)
>
> diff --git a/arch/arm/include/asm/efi.h b/arch/arm/include/asm/efi.h
> index 3ee4f4381985..0496bc96a092 100644
> --- a/arch/arm/include/asm/efi.h
> +++ b/arch/arm/include/asm/efi.h
> @@ -74,12 +74,6 @@ static inline void efifb_setup_from_dmi(struct screen_info *si, const char *opt)
>   */
>  #define EFI_PHYS_ALIGN         SZ_16M
>
> -/* on ARM, the FDT should be located in a lowmem region */
> -static inline unsigned long efi_get_max_fdt_addr(unsigned long image_addr)
> -{
> -       return round_down(image_addr, EFI_PHYS_ALIGN) + SZ_512M;
> -}
> -
>  /* on ARM, the initrd should be loaded in a lowmem region */
>  static inline unsigned long efi_get_max_initrd_addr(unsigned long image_addr)
>  {
> diff --git a/arch/arm64/include/asm/efi.h b/arch/arm64/include/asm/efi.h
> index 973b14415271..01446a073b2e 100644
> --- a/arch/arm64/include/asm/efi.h
> +++ b/arch/arm64/include/asm/efi.h
> @@ -64,12 +64,6 @@ efi_status_t __efi_rt_asm_wrapper(void *, const char *, ...);
>  #define EFI_KIMG_ALIGN \
>         (SEGMENT_ALIGN > THREAD_ALIGN ? SEGMENT_ALIGN : THREAD_ALIGN)
>
> -/* on arm64, the FDT may be located anywhere in system RAM */
> -static inline unsigned long efi_get_max_fdt_addr(unsigned long image_addr)
> -{
> -       return ULONG_MAX;
> -}
> -
>  /*
>   * On arm64, we have to ensure that the initrd ends up in the linear region,
>   * which is a 1 GB aligned region of size '1UL << (VA_BITS_MIN - 1)' that is
> diff --git a/arch/riscv/include/asm/efi.h b/arch/riscv/include/asm/efi.h
> index 7542282f1141..6d98cd999680 100644
> --- a/arch/riscv/include/asm/efi.h
> +++ b/arch/riscv/include/asm/efi.h
> @@ -27,12 +27,6 @@ int efi_set_mapping_permissions(struct mm_struct *mm, efi_memory_desc_t *md);
>
>  #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 image_addr)
> -{
> -       return ULONG_MAX;
> -}
> -
>  /* Load initrd at enough distance from DRAM start */
>  static inline unsigned long efi_get_max_initrd_addr(unsigned long image_addr)
>  {
> diff --git a/drivers/firmware/efi/libstub/efi-stub.c b/drivers/firmware/efi/libstub/efi-stub.c
> index 914a343c7785..ec2f3985bef3 100644
> --- a/drivers/firmware/efi/libstub/efi-stub.c
> +++ b/drivers/firmware/efi/libstub/efi-stub.c
> @@ -273,7 +273,6 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
>         install_memreserve_table();
>
>         status = allocate_new_fdt_and_exit_boot(handle, &fdt_addr,
> -                                               efi_get_max_fdt_addr(image_addr),
>                                                 initrd_addr, initrd_size,
>                                                 cmdline_ptr, fdt_addr, fdt_size);
>         if (status != EFI_SUCCESS)
> diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h
> index 2d7abcd99de9..c1c63e847481 100644
> --- a/drivers/firmware/efi/libstub/efistub.h
> +++ b/drivers/firmware/efi/libstub/efistub.h
> @@ -750,7 +750,6 @@ efi_status_t efi_exit_boot_services(void *handle,
>
>  efi_status_t allocate_new_fdt_and_exit_boot(void *handle,
>                                             unsigned long *new_fdt_addr,
> -                                           unsigned long max_addr,
>                                             u64 initrd_addr, u64 initrd_size,
>                                             char *cmdline_ptr,
>                                             unsigned long fdt_addr,
> diff --git a/drivers/firmware/efi/libstub/fdt.c b/drivers/firmware/efi/libstub/fdt.c
> index 368cd60000ee..365c3a43a198 100644
> --- a/drivers/firmware/efi/libstub/fdt.c
> +++ b/drivers/firmware/efi/libstub/fdt.c
> @@ -238,7 +238,6 @@ static efi_status_t exit_boot_func(struct efi_boot_memmap *map,
>
>  efi_status_t allocate_new_fdt_and_exit_boot(void *handle,
>                                             unsigned long *new_fdt_addr,
> -                                           unsigned long max_addr,
>                                             u64 initrd_addr, u64 initrd_size,
>                                             char *cmdline_ptr,
>                                             unsigned long fdt_addr,
> @@ -275,7 +274,7 @@ efi_status_t allocate_new_fdt_and_exit_boot(void *handle,
>         efi_info("Exiting boot services and installing virtual address map...\n");
>
>         map.map = &memory_map;
> -       status = efi_allocate_pages(MAX_FDT_SIZE, new_fdt_addr, max_addr);
> +       status = efi_allocate_pages(MAX_FDT_SIZE, new_fdt_addr, ULONG_MAX);
>         if (status != EFI_SUCCESS) {
>                 efi_err("Unable to allocate memory for new device tree.\n");
>                 goto fail;
> --
> 2.17.1
>

Reviewed-by: Atish Patra <atish.patra@wdc.com>