On Fri, 17 Jun 2022 at 16:56, Huacai Chen <chenhuacai@xxxxxxxxxxx> wrote: > > This patch adds efistub booting support, which is the standard UEFI boot > protocol for us to use. > > We use generic efistub, which means we can pass boot information (i.e., > system table, memory map, kernel command line, initrd) via a light FDT > and drop a lot of non-standard code. > > We use a flat mapping to map the efi runtime in the kernel's address > space. In efi, VA = PA; in kernel, VA = PA + PAGE_OFFSET. As a result, > flat mapping is not identity mapping, SetVirtualAddressMap() is still > needed for the efi runtime. > > Currently, generic efistub doesn't support mapping efi runtime in the > kernel. So we set efi_novamap to not call SetVirtualAddressMap() in the > stub. Instead, we call it in the core kernel. This also makes the raw > elf kernel booting be possible, which is needed by non-UEFI firmware > (e.g., PMON which is widely used by Loongson for historic reasons). > > Then how the elf kernel and the efi kernel co-exist? When building, the > raw vmlinux is naturally in elf format, the efi kernel is generated from > vmlinux by objcopy via removing the elf header. > > Note: The magic number in MSDOS header is used by Grub [1], which is the > same as RISC-V and ARM64. > > [1] https://lists.gnu.org/archive/html/grub-devel/2021-10/msg00215.html > That patch was never merged. Today, arm64 is the only arch in GRUB that uses EFI boot exclusively, and requires an additional magic number in the PE/COFF header. This is a mistake, which makes it difficult, e.g., to implement a generic EFI decompressor. The magic number signifies that the image implements the bare metal boot protocol, which GRUB does not implement. So it should not check for the magic number. I sent a patch for that here: https://lists.gnu.org/archive/html/grub-devel/2022-08/msg00113.html Please don't copy the same mistake in your GRUB port. > Signed-off-by: Huacai Chen <chenhuacai@xxxxxxxxxxx> > --- > arch/loongarch/Kconfig | 9 ++ > arch/loongarch/Makefile | 5 + > arch/loongarch/boot/Makefile | 4 + > arch/loongarch/kernel/efi-header.S | 101 ++++++++++++++ > arch/loongarch/kernel/efi.c | 126 +++++++++++++++++- > arch/loongarch/kernel/head.S | 26 ++++ > arch/loongarch/kernel/image-vars.h | 29 ++++ > arch/loongarch/kernel/vmlinux.lds.S | 1 + > drivers/firmware/efi/Kconfig | 2 +- > drivers/firmware/efi/libstub/Makefile | 10 ++ > .../firmware/efi/libstub/efi-stub-helper.c | 2 +- > drivers/firmware/efi/libstub/efi-stub.c | 4 +- > drivers/firmware/efi/libstub/loongarch-stub.c | 88 ++++++++++++ > include/linux/efi.h | 1 + > include/linux/pe.h | 2 + > 15 files changed, 405 insertions(+), 5 deletions(-) > create mode 100644 arch/loongarch/kernel/efi-header.S > create mode 100644 arch/loongarch/kernel/image-vars.h > create mode 100644 drivers/firmware/efi/libstub/loongarch-stub.c > > diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig > index 1ec220df751d..faee7fa4c004 100644 > --- a/arch/loongarch/Kconfig > +++ b/arch/loongarch/Kconfig > @@ -305,6 +305,15 @@ config EFI > This enables the kernel to use EFI runtime services that are > available (such as the EFI variable services). > > +config EFI_STUB > + bool "EFI boot stub support" > + default y > + depends on EFI > + select EFI_GENERIC_STUB > + help > + This kernel feature allows the kernel to be loaded directly by > + EFI firmware without the use of a bootloader. > + > config SMP > bool "Multi-Processing support" > help > diff --git a/arch/loongarch/Makefile b/arch/loongarch/Makefile > index fbe4277e6404..c1bda54893ec 100644 > --- a/arch/loongarch/Makefile > +++ b/arch/loongarch/Makefile > @@ -7,7 +7,11 @@ boot := arch/loongarch/boot > > KBUILD_DEFCONFIG := loongson3_defconfig > > +ifndef CONFIG_EFI_STUB > KBUILD_IMAGE = $(boot)/vmlinux > +else > +KBUILD_IMAGE = $(boot)/vmlinux.efi > +endif > I think this needs to be cleaned up. Calling your abstract non-EFI build target 'vmlinux' is going to clash with the actual file called vmlinux. So I suggest to rename this to vmlinux.elf and vmlinux.efi. > # > # Select the object file format to substitute into the linker script. > @@ -73,6 +77,7 @@ endif > head-y := arch/loongarch/kernel/head.o > > libs-y += arch/loongarch/lib/ > +libs-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a > > ifeq ($(KBUILD_EXTMOD),) > prepare: vdso_prepare > diff --git a/arch/loongarch/boot/Makefile b/arch/loongarch/boot/Makefile > index 0125b17edc98..b39d50a7a3df 100644 > --- a/arch/loongarch/boot/Makefile > +++ b/arch/loongarch/boot/Makefile > @@ -14,3 +14,7 @@ quiet_cmd_strip = STRIP $@ > > $(obj)/vmlinux: vmlinux FORCE > $(call if_changed,strip) > + > +targets += vmlinux.efi > +$(obj)/vmlinux.efi: $(obj)/vmlinux FORCE > + $(call if_changed,objcopy) Same here (.elf vs .efi) > diff --git a/arch/loongarch/kernel/efi-header.S b/arch/loongarch/kernel/efi-header.S > new file mode 100644 > index 000000000000..ef48dc72455b > --- /dev/null > +++ b/arch/loongarch/kernel/efi-header.S > @@ -0,0 +1,101 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* > + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited > + */ > + > +#include <linux/pe.h> > +#include <linux/sizes.h> > + > + .macro __EFI_PE_HEADER > + .long PE_MAGIC > +.Lcoff_header: > +#ifdef CONFIG_32BIT > + .short IMAGE_FILE_MACHINE_LOONGARCH32 /* Machine */ > +#else > + .short IMAGE_FILE_MACHINE_LOONGARCH64 /* Machine */ > +#endif Please drop the 32-bit version here. 32-bit binaries use PE32 not PE32+ so this header is not 32-bit compatible anway > + .short .Lsection_count /* NumberOfSections */ > + .long 0 /* TimeDateStamp */ > + .long 0 /* PointerToSymbolTable */ > + .long 0 /* NumberOfSymbols */ > + .short .Lsection_table - .Loptional_header /* SizeOfOptionalHeader */ > + .short IMAGE_FILE_DEBUG_STRIPPED | \ > + IMAGE_FILE_EXECUTABLE_IMAGE | \ > + IMAGE_FILE_LINE_NUMS_STRIPPED /* Characteristics */ > + > +.Loptional_header: > + .short PE_OPT_MAGIC_PE32PLUS /* PE32+ format */ > + .byte 0x02 /* MajorLinkerVersion */ > + .byte 0x14 /* MinorLinkerVersion */ > + .long __inittext_end - .Lefi_header_end /* SizeOfCode */ > + .long _end - __initdata_begin /* SizeOfInitializedData */ > + .long 0 /* SizeOfUninitializedData */ > + .long __efistub_efi_pe_entry - _head /* AddressOfEntryPoint */ > + .long .Lefi_header_end - _head /* BaseOfCode */ > + > +.Lextra_header_fields: > + .quad 0 /* ImageBase */ > + .long PECOFF_SEGMENT_ALIGN /* SectionAlignment */ > + .long PECOFF_FILE_ALIGN /* FileAlignment */ > + .short 0 /* MajorOperatingSystemVersion */ > + .short 0 /* MinorOperatingSystemVersion */ > + .short LINUX_EFISTUB_MAJOR_VERSION /* MajorImageVersion */ > + .short LINUX_EFISTUB_MINOR_VERSION /* MinorImageVersion */ > + .short 0 /* MajorSubsystemVersion */ > + .short 0 /* MinorSubsystemVersion */ > + .long 0 /* Win32VersionValue */ > + > + .long _end - _head /* SizeOfImage */ > + > + /* Everything before the kernel image is considered part of the header */ > + .long .Lefi_header_end - _head /* SizeOfHeaders */ > + .long 0 /* CheckSum */ > + .short IMAGE_SUBSYSTEM_EFI_APPLICATION /* Subsystem */ > + .short 0 /* DllCharacteristics */ > + .quad 0 /* SizeOfStackReserve */ > + .quad 0 /* SizeOfStackCommit */ > + .quad 0 /* SizeOfHeapReserve */ > + .quad 0 /* SizeOfHeapCommit */ > + .long 0 /* LoaderFlags */ > + .long (.Lsection_table - .) / 8 /* NumberOfRvaAndSizes */ > + > + .quad 0 /* ExportTable */ > + .quad 0 /* ImportTable */ > + .quad 0 /* ResourceTable */ > + .quad 0 /* ExceptionTable */ > + .quad 0 /* CertificationTable */ > + .quad 0 /* BaseRelocationTable */ > + > + /* Section table */ > +.Lsection_table: > + .ascii ".text\0\0\0" > + .long __inittext_end - .Lefi_header_end /* VirtualSize */ > + .long .Lefi_header_end - _head /* VirtualAddress */ > + .long __inittext_end - .Lefi_header_end /* SizeOfRawData */ > + .long .Lefi_header_end - _head /* PointerToRawData */ > + > + .long 0 /* PointerToRelocations */ > + .long 0 /* PointerToLineNumbers */ > + .short 0 /* NumberOfRelocations */ > + .short 0 /* NumberOfLineNumbers */ > + .long IMAGE_SCN_CNT_CODE | \ > + IMAGE_SCN_MEM_READ | \ > + IMAGE_SCN_MEM_EXECUTE /* Characteristics */ > + > + .ascii ".data\0\0\0" > + .long _end - __initdata_begin /* VirtualSize */ > + .long __initdata_begin - _head /* VirtualAddress */ > + .long _edata - __initdata_begin /* SizeOfRawData */ > + .long __initdata_begin - _head /* PointerToRawData */ > + > + .long 0 /* PointerToRelocations */ > + .long 0 /* PointerToLineNumbers */ > + .short 0 /* NumberOfRelocations */ > + .short 0 /* NumberOfLineNumbers */ > + .long IMAGE_SCN_CNT_INITIALIZED_DATA | \ > + IMAGE_SCN_MEM_READ | \ > + IMAGE_SCN_MEM_WRITE /* Characteristics */ > + > + .set .Lsection_count, (. - .Lsection_table) / 40 > +.Lefi_header_end: This symbol needs to be section aligned, or the section header fields will be off. Even if it works today, the PE/COFF spec requires the section's VirtualSize and VirtualAddress fields to be section aligned. > + .endm > diff --git a/arch/loongarch/kernel/efi.c b/arch/loongarch/kernel/efi.c > index a50b60c587fa..42f7cfe9ab03 100644 > --- a/arch/loongarch/kernel/efi.c > +++ b/arch/loongarch/kernel/efi.c > @@ -22,19 +22,141 @@ > > #include <asm/early_ioremap.h> > #include <asm/efi.h> > +#include <asm/tlb.h> > #include <asm/loongson.h> > > static unsigned long efi_nr_tables; > static unsigned long efi_config_table; > +static unsigned long screen_info_table __initdata = EFI_INVALID_TABLE_ADDR; > > static efi_system_table_t *efi_systab; > -static efi_config_table_type_t arch_tables[] __initdata = {{},}; > +static efi_config_table_type_t arch_tables[] __initdata = { > + {LINUX_EFI_LARCH_SCREEN_INFO_TABLE_GUID, &screen_info_table, "SINFO"}, > + {}, > +}; > + > +static void __init init_screen_info(void) > +{ > + struct screen_info *si; > + > + if (screen_info_table == EFI_INVALID_TABLE_ADDR) > + return; > + > + si = early_memremap_ro(screen_info_table, sizeof(*si)); > + if (!si) { > + pr_err("Could not map screen_info config table\n"); > + return; > + } > + screen_info = *si; > + early_memunmap(si, sizeof(*si)); > + > + if (screen_info.orig_video_isVGA == VIDEO_TYPE_EFI) > + memblock_reserve(screen_info.lfb_base, screen_info.lfb_size); > +} > + The above may be unnecessary - the EFI stub is part of the core kernel image, so you can access screen_info directly (please refer to the arm64 port for an example) > +static void __init create_tlb(u32 index, u64 vppn, u32 ps, u32 mat) > +{ > + unsigned long tlblo0, tlblo1; > + > + write_csr_pagesize(ps); > + > + tlblo0 = vppn | CSR_TLBLO0_V | CSR_TLBLO0_WE | > + CSR_TLBLO0_GLOBAL | (mat << CSR_TLBLO0_CCA_SHIFT); > + tlblo1 = tlblo0 + (1 << ps); > + > + csr_write64(vppn, LOONGARCH_CSR_TLBEHI); > + csr_write64(tlblo0, LOONGARCH_CSR_TLBELO0); > + csr_write64(tlblo1, LOONGARCH_CSR_TLBELO1); > + csr_xchg32(0, CSR_TLBIDX_EHINV, LOONGARCH_CSR_TLBIDX); > + csr_xchg32(index, CSR_TLBIDX_IDX, LOONGARCH_CSR_TLBIDX); > + > + tlb_write_indexed(); > +} > + > +#define MTLB_ENTRY_INDEX 0x800 > + > +/* Create VA == PA mapping as UEFI */ > +static void __init fix_efi_mapping(void) > +{ > + unsigned int index = MTLB_ENTRY_INDEX; > + unsigned int tlbnr = boot_cpu_data.tlbsizemtlb - 2; > + unsigned long i, vppn; > + > + /* Low Memory, Cached */ > + create_tlb(index++, 0x00000000, PS_128M, 1); > + /* MMIO Registers, Uncached */ > + create_tlb(index++, 0x10000000, PS_128M, 0); > + > + /* High Memory, Cached */ > + for (i = 0; i < tlbnr; i++) { > + vppn = 0x80000000ULL + (i * SZ_2G); > + create_tlb(index++, vppn, PS_1G, 1); > + } > +} > + > +/* > + * set_virtual_map() - create a virtual mapping for the EFI memory map and call > + * efi_set_virtual_address_map enter virtual for runtime service > + * > + * This function populates the virt_addr fields of all memory region descriptors > + * in @memory_map whose EFI_MEMORY_RUNTIME attribute is set. Those descriptors > + * are also copied to @runtime_map, and their total count is returned in @count. > + */ You mentioned before that this must be done in the core kernel and not in the EFI stub, but I don't remember the reason. Can you add a comment here why the below conversions cannot be done by the EFI stub? Doing this in the stub removes the need to set up a 1:1 mapping just for a single invocation of SetVirtualAddressMap(), so if there is any way to move this into the stub, I would strongly prefer it. > +static int __init set_virtual_map(void) > +{ > + int count = 0; > + unsigned int size; > + unsigned long attr; > + efi_status_t status; > + efi_runtime_services_t *rt; > + efi_set_virtual_address_map_t *svam; > + efi_memory_desc_t *in, runtime_map[32]; > + > + size = sizeof(efi_memory_desc_t); > + > + for_each_efi_memory_desc(in) { > + attr = in->attribute; > + if (!(attr & EFI_MEMORY_RUNTIME)) > + continue; > + > + if (attr & (EFI_MEMORY_WB | EFI_MEMORY_WT)) > + in->virt_addr = TO_CACHE(in->phys_addr); > + else > + in->virt_addr = TO_UNCACHE(in->phys_addr); > + > + memcpy(&runtime_map[count++], in, size); > + } > + > + rt = early_memremap_ro((unsigned long)efi_systab->runtime, sizeof(*rt)); > + > + /* Install the new virtual address map */ > + svam = rt->set_virtual_address_map; > + > + fix_efi_mapping(); > + > + status = svam(size * count, size, efi.memmap.desc_version, > + (efi_memory_desc_t *)TO_PHYS((unsigned long)runtime_map)); > + > + local_flush_tlb_all(); > + write_csr_pagesize(PS_DEFAULT_SIZE); > + > + return 0; > +} > > void __init efi_runtime_init(void) > { > + int status; > + > if (!efi_enabled(EFI_BOOT)) > return; > > + if (!efi_systab->runtime) > + return; > + > + status = set_virtual_map(); > + if (status < 0) > + return; > + > if (efi_runtime_disabled()) { > pr_info("EFI runtime services will be disabled.\n"); > return; > @@ -69,4 +191,6 @@ void __init efi_init(void) > config_tables = early_memremap(efi_config_table, efi_nr_tables * size); > efi_config_parse_tables(config_tables, efi_systab->nr_tables, arch_tables); > early_memunmap(config_tables, efi_nr_tables * size); > + > + init_screen_info(); > } > diff --git a/arch/loongarch/kernel/head.S b/arch/loongarch/kernel/head.S > index e596dfcd924b..ccc425027553 100644 > --- a/arch/loongarch/kernel/head.S > +++ b/arch/loongarch/kernel/head.S > @@ -12,6 +12,32 @@ > #include <asm/loongarch.h> > #include <asm/stackframe.h> > > +#ifdef CONFIG_EFI_STUB > + > +#include "efi-header.S" > + > + __HEAD > + > +_head: > + .word MZ_MAGIC /* "MZ", MS-DOS header */ > + .org 0x38 > +#ifdef CONFIG_32BIT > + .ascii "LA32" /* Magic number for BootLoader */ > +#else > + .ascii "LA64" /* Magic number for BootLoader */ > +#endif As explained above, please remove these. > + .org 0x3c > + .long pe_header - _head /* Offset to the PE header */ > + > +pe_header: > + __EFI_PE_HEADER > + > +SYM_DATA(kernel_asize, .long _end - _text); > +SYM_DATA(kernel_fsize, .long _edata - _text); > +SYM_DATA(kernel_offset, .long kernel_offset - _text); > + > +#endif > + > __REF > > SYM_ENTRY(_stext, SYM_L_GLOBAL, SYM_A_NONE) > diff --git a/arch/loongarch/kernel/image-vars.h b/arch/loongarch/kernel/image-vars.h > new file mode 100644 > index 000000000000..104e9f0e97fe > --- /dev/null > +++ b/arch/loongarch/kernel/image-vars.h > @@ -0,0 +1,29 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > +/* > + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited > + */ > +#ifndef __LOONGARCH_KERNEL_IMAGE_VARS_H > +#define __LOONGARCH_KERNEL_IMAGE_VARS_H > + > +#ifdef CONFIG_EFI_STUB > + > +__efistub_memcmp = memcmp; > +__efistub_memchr = memchr; > +__efistub_memcpy = memcpy; > +__efistub_memmove = memmove; > +__efistub_memset = memset; > +__efistub_strcat = strcat; > +__efistub_strcmp = strcmp; > +__efistub_strlen = strlen; > +__efistub_strncat = strncat; > +__efistub_strnstr = strnstr; > +__efistub_strnlen = strnlen; > +__efistub_strrchr = strrchr; > +__efistub_kernel_entry = kernel_entry; > +__efistub_kernel_asize = kernel_asize; > +__efistub_kernel_fsize = kernel_fsize; > +__efistub_kernel_offset = kernel_offset; > + > +#endif > + > +#endif /* __LOONGARCH_KERNEL_IMAGE_VARS_H */ > diff --git a/arch/loongarch/kernel/vmlinux.lds.S b/arch/loongarch/kernel/vmlinux.lds.S > index 78311a6101a3..9dfa5b886c09 100644 > --- a/arch/loongarch/kernel/vmlinux.lds.S > +++ b/arch/loongarch/kernel/vmlinux.lds.S > @@ -12,6 +12,7 @@ > #define BSS_FIRST_SECTIONS *(.bss..swapper_pg_dir) > > #include <asm-generic/vmlinux.lds.h> > +#include "image-vars.h" > > /* > * Max avaliable Page Size is 64K, so we set SectionAlignment > diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig > index 7aa4717cdcac..9e4645e5a5c0 100644 > --- a/drivers/firmware/efi/Kconfig > +++ b/drivers/firmware/efi/Kconfig > @@ -118,7 +118,7 @@ config EFI_GENERIC_STUB > > config EFI_ARMSTUB_DTB_LOADER > bool "Enable the DTB loader" > - depends on EFI_GENERIC_STUB && !RISCV > + depends on EFI_GENERIC_STUB && !RISCV && !LOONGARCH > default y > help > Select this config option to add support for the dtb= command Please make the initrd command line loader depend on !LOONGARCH. systemd-boot already supports this, and GRUB patches are on the list (the one you quoted above is part of the series that adds support for it). Your QEMU/edk2 firmware port also implements support for the LoadFile2 based method. > diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile > index d0537573501e..1588c61939e7 100644 > --- a/drivers/firmware/efi/libstub/Makefile > +++ b/drivers/firmware/efi/libstub/Makefile > @@ -26,6 +26,8 @@ cflags-$(CONFIG_ARM) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ > $(call cc-option,-mno-single-pic-base) > cflags-$(CONFIG_RISCV) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ > -fpic > +cflags-$(CONFIG_LOONGARCH) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ > + -fpic > > cflags-$(CONFIG_EFI_GENERIC_STUB) += -I$(srctree)/scripts/dtc/libfdt > > @@ -70,6 +72,8 @@ lib-$(CONFIG_ARM) += arm32-stub.o > lib-$(CONFIG_ARM64) += arm64-stub.o > lib-$(CONFIG_X86) += x86-stub.o > lib-$(CONFIG_RISCV) += riscv-stub.o > +lib-$(CONFIG_LOONGARCH) += loongarch-stub.o > + > CFLAGS_arm32-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET) > > # Even when -mbranch-protection=none is set, Clang will generate a > @@ -125,6 +129,12 @@ STUBCOPY_FLAGS-$(CONFIG_RISCV) += --prefix-alloc-sections=.init \ > --prefix-symbols=__efistub_ > STUBCOPY_RELOC-$(CONFIG_RISCV) := R_RISCV_HI20 > > +# For LoongArch, keep all the symbols in .init section and make sure that no > +# absolute symbols references doesn't exist. > +STUBCOPY_FLAGS-$(CONFIG_LOONGARCH) += --prefix-alloc-sections=.init \ > + --prefix-symbols=__efistub_ > +STUBCOPY_RELOC-$(CONFIG_LOONGARCH) := R_LARCH_MARK_LA > + > $(obj)/%.stub.o: $(obj)/%.o FORCE > $(call if_changed,stubcopy) > > diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c > index 3d972061c1b0..f612cfceda22 100644 > --- a/drivers/firmware/efi/libstub/efi-stub-helper.c > +++ b/drivers/firmware/efi/libstub/efi-stub-helper.c > @@ -21,7 +21,7 @@ > bool efi_nochunk; > bool efi_nokaslr = !IS_ENABLED(CONFIG_RANDOMIZE_BASE); > int efi_loglevel = CONSOLE_LOGLEVEL_DEFAULT; > -bool efi_novamap; > +bool efi_novamap = IS_ENABLED(CONFIG_LOONGARCH); /* LoongArch call svam() in kernel */ > > static bool efi_noinitrd; > static bool efi_nosoftreserve; > diff --git a/drivers/firmware/efi/libstub/efi-stub.c b/drivers/firmware/efi/libstub/efi-stub.c > index f515394cce6e..730b7bd21776 100644 > --- a/drivers/firmware/efi/libstub/efi-stub.c > +++ b/drivers/firmware/efi/libstub/efi-stub.c > @@ -40,9 +40,9 @@ > > #ifdef CONFIG_ARM64 > # define EFI_RT_VIRTUAL_LIMIT DEFAULT_MAP_WINDOW_64 > -#elif defined(CONFIG_RISCV) > +#elif defined(CONFIG_RISCV) || defined(CONFIG_LOONGARCH) > # define EFI_RT_VIRTUAL_LIMIT TASK_SIZE_MIN > -#else > +#else /* Only if TASK_SIZE is a constant */ > # define EFI_RT_VIRTUAL_LIMIT TASK_SIZE > #endif > > diff --git a/drivers/firmware/efi/libstub/loongarch-stub.c b/drivers/firmware/efi/libstub/loongarch-stub.c > new file mode 100644 > index 000000000000..beee086d9950 > --- /dev/null > +++ b/drivers/firmware/efi/libstub/loongarch-stub.c > @@ -0,0 +1,88 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Author: Yun Liu <liuyun@xxxxxxxxxxx> > + * Huacai Chen <chenhuacai@xxxxxxxxxxx> > + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited > + */ > + > +#include <linux/efi.h> > +#include <asm/efi.h> > +#include <asm/addrspace.h> > +#include "efistub.h" > + > +typedef void __noreturn (*kernel_entry_t)(bool efi, unsigned long fdt); > + > +extern int kernel_asize; > +extern int kernel_fsize; > +extern int kernel_offset; > +extern kernel_entry_t kernel_entry; > + > +static efi_guid_t screen_info_guid = LINUX_EFI_LARCH_SCREEN_INFO_TABLE_GUID; > + > +struct screen_info *alloc_screen_info(void) > +{ > + efi_status_t status; > + struct screen_info *si; > + > + status = efi_bs_call(allocate_pool, > + EFI_RUNTIME_SERVICES_DATA, sizeof(*si), (void **)&si); > + if (status != EFI_SUCCESS) > + return NULL; > + > + status = efi_bs_call(install_configuration_table, &screen_info_guid, si); > + if (status == EFI_SUCCESS) > + return si; > + > + efi_bs_call(free_pool, si); > + > + return NULL; > +} > + > +void free_screen_info(struct screen_info *si) > +{ > + if (!si) > + return; > + > + efi_bs_call(install_configuration_table, &screen_info_guid, NULL); > + efi_bs_call(free_pool, si); > +} > + As indicated above, I think you can adopt the arm64 approach here instead. > +efi_status_t check_platform_features(void) > +{ > + /* Config Direct Mapping */ > + csr_write64(CSR_DMW0_INIT, LOONGARCH_CSR_DMWIN0); > + csr_write64(CSR_DMW1_INIT, LOONGARCH_CSR_DMWIN1); > + > + return EFI_SUCCESS; > +} > + This code is not checking a platform feature so it does not belong here. The EFI stub code is an ordinary EFI app, and it runs in the execution context provided by EFI. So why is this needed so early? Can you move it into the kernel entry routine instead? > +efi_status_t handle_kernel_image(unsigned long *image_addr, > + unsigned long *image_size, > + unsigned long *reserve_addr, > + unsigned long *reserve_size, > + efi_loaded_image_t *image, > + efi_handle_t image_handle) > +{ > + efi_status_t status; > + unsigned long kernel_addr = 0; > + > + kernel_addr = (unsigned long)&kernel_offset - kernel_offset; > + > + status = efi_relocate_kernel(&kernel_addr, kernel_fsize, kernel_asize, > + PHYSADDR(VMLINUX_LOAD_ADDRESS), SZ_2M, 0x0); > + > + *image_addr = kernel_addr; > + *image_size = kernel_asize; > + > + return status; > +} > + > +void __noreturn efi_enter_kernel(unsigned long entrypoint, unsigned long fdt, unsigned long fdt_size) > +{ > + kernel_entry_t real_kernel_entry; > + > + real_kernel_entry = (kernel_entry_t) > + ((unsigned long)&kernel_entry - entrypoint + VMLINUX_LOAD_ADDRESS); > + > + real_kernel_entry(true, fdt); > +} > diff --git a/include/linux/efi.h b/include/linux/efi.h > index 7d9b0bb47eb3..adc43641ef8c 100644 > --- a/include/linux/efi.h > +++ b/include/linux/efi.h > @@ -401,6 +401,7 @@ void efi_native_runtime_setup(void); > * associated with ConOut > */ > #define LINUX_EFI_ARM_SCREEN_INFO_TABLE_GUID EFI_GUID(0xe03fc20a, 0x85dc, 0x406e, 0xb9, 0x0e, 0x4a, 0xb5, 0x02, 0x37, 0x1d, 0x95) > +#define LINUX_EFI_LARCH_SCREEN_INFO_TABLE_GUID EFI_GUID(0x07fd51a6, 0x9532, 0x926f, 0x51, 0xdc, 0x6a, 0x63, 0x60, 0x2f, 0x84, 0xb4) > #define LINUX_EFI_ARM_CPU_STATE_TABLE_GUID EFI_GUID(0xef79e4aa, 0x3c3d, 0x4989, 0xb9, 0x02, 0x07, 0xa9, 0x43, 0xe5, 0x50, 0xd2) > #define LINUX_EFI_LOADER_ENTRY_GUID EFI_GUID(0x4a67b082, 0x0a4c, 0x41cf, 0xb6, 0xc7, 0x44, 0x0b, 0x29, 0xbb, 0x8c, 0x4f) > #define LINUX_EFI_RANDOM_SEED_TABLE_GUID EFI_GUID(0x1ce1e5bc, 0x7ceb, 0x42f2, 0x81, 0xe5, 0x8a, 0xad, 0xf1, 0x80, 0xf5, 0x7b) > diff --git a/include/linux/pe.h b/include/linux/pe.h > index daf09ffffe38..1d3836ef9d92 100644 > --- a/include/linux/pe.h > +++ b/include/linux/pe.h > @@ -65,6 +65,8 @@ > #define IMAGE_FILE_MACHINE_SH5 0x01a8 > #define IMAGE_FILE_MACHINE_THUMB 0x01c2 > #define IMAGE_FILE_MACHINE_WCEMIPSV2 0x0169 > +#define IMAGE_FILE_MACHINE_LOONGARCH32 0x6232 > +#define IMAGE_FILE_MACHINE_LOONGARCH64 0x6264 > > /* flags */ > #define IMAGE_FILE_RELOCS_STRIPPED 0x0001 > -- > 2.27.0 >
