Merge tag 'efi-loongarch-for-v6.1' into efi/next

EFI boot support for loongarch

arch/loongarch/Kconfig

@@ -317,6 +317,15 @@ 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

arch/loongarch/Makefile

@@ -7,7 +7,11 @@ boot	:= arch/loongarch/boot
 
 KBUILD_DEFCONFIG := loongson3_defconfig
 
-KBUILD_IMAGE	= $(boot)/vmlinux
+ifndef CONFIG_EFI_STUB
+KBUILD_IMAGE	:= $(boot)/vmlinux.elf
+else
+KBUILD_IMAGE	:= $(boot)/vmlinux.efi
+endif
 
 #
 # Select the object file format to substitute into the linker script.
@@ -75,6 +79,7 @@ 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
@@ -86,10 +91,10 @@ PHONY += vdso_install
 vdso_install:
 	$(Q)$(MAKE) $(build)=arch/loongarch/vdso $@
 
-all:	$(KBUILD_IMAGE)
+all:	$(notdir $(KBUILD_IMAGE))
 
-$(KBUILD_IMAGE): vmlinux
-	$(Q)$(MAKE) $(build)=$(boot) $(bootvars-y) $@
+vmlinux.elf vmlinux.efi: vmlinux
+	$(Q)$(MAKE) $(build)=$(boot) $(bootvars-y) $(boot)/$@
 
 install:
 	$(Q)install -D -m 755 $(KBUILD_IMAGE) $(INSTALL_PATH)/vmlinux-$(KERNELRELEASE)

arch/loongarch/boot/Makefile

@@ -8,9 +8,13 @@ drop-sections := .comment .note .options .note.gnu.build-id
 strip-flags   := $(addprefix --remove-section=,$(drop-sections)) -S
 OBJCOPYFLAGS_vmlinux.efi := -O binary $(strip-flags)
 
-targets := vmlinux
 quiet_cmd_strip = STRIP	  $@
       cmd_strip = $(STRIP) -s -o $@ $<
 
-$(obj)/vmlinux: vmlinux FORCE
+targets := vmlinux.elf
+$(obj)/vmlinux.elf: vmlinux FORCE
 	$(call if_changed,strip)
+
+targets += vmlinux.efi
+$(obj)/vmlinux.efi: vmlinux FORCE
+	$(call if_changed,objcopy)

arch/loongarch/include/asm/efi.h

@@ -17,9 +17,16 @@ void efifb_setup_from_dmi(struct screen_info *si, const char *opt);
 #define arch_efi_call_virt_teardown()
 
 #define EFI_ALLOC_ALIGN		SZ_64K
+#define EFI_RT_VIRTUAL_OFFSET	CSR_DMW0_BASE
 
-struct screen_info *alloc_screen_info(void);
-void free_screen_info(struct screen_info *si);
+static inline struct screen_info *alloc_screen_info(void)
+{
+	return &screen_info;
+}
+
+static inline void free_screen_info(struct screen_info *si)
+{
+}
 
 static inline unsigned long efi_get_max_initrd_addr(unsigned long image_addr)
 {

arch/loongarch/kernel/efi-header.S

+/* 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:
+	.short	IMAGE_FILE_MACHINE_LOONGARCH64		/* Machine */
+	.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
+
+	.balign	0x10000					/* PECOFF_SEGMENT_ALIGN */
+.Lefi_header_end:
+	.endm

arch/loongarch/kernel/efi.c

@@ -69,4 +69,7 @@ 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);
+
+	if (screen_info.orig_video_isVGA == VIDEO_TYPE_EFI)
+		memblock_reserve(screen_info.lfb_base, screen_info.lfb_size);
 }

arch/loongarch/kernel/head.S

@@ -12,6 +12,26 @@
 #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	0x3c			/* 0x04 ~ 0x3b reserved */
+	.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_CODE_START(kernel_entry)			# kernel entry point

arch/loongarch/kernel/image-vars.h

+/* 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;
+__efistub_screen_info		= screen_info;
+
+#endif
+
+#endif /* __LOONGARCH_KERNEL_IMAGE_VARS_H */

arch/loongarch/kernel/setup.c

@@ -49,9 +49,7 @@
 #define SMBIOS_CORE_PACKAGE_OFFSET	0x23
 #define LOONGSON_EFI_ENABLE		(1 << 3)
 
-#ifdef CONFIG_VT
-struct screen_info screen_info;
-#endif
+struct screen_info screen_info __section(".data");
 
 unsigned long fw_arg0, fw_arg1;
 DEFINE_PER_CPU(unsigned long, kernelsp);
@@ -122,16 +120,9 @@ static void __init parse_cpu_table(const struct dmi_header *dm)
 
 static void __init parse_bios_table(const struct dmi_header *dm)
 {
-	int bios_extern;
 	char *dmi_data = (char *)dm;
 
-	bios_extern = *(dmi_data + SMBIOS_BIOSEXTERN_OFFSET);
 	b_info.bios_size = (*(dmi_data + SMBIOS_BIOSSIZE_OFFSET) + 1) << 6;
-
-	if (bios_extern & LOONGSON_EFI_ENABLE)
-		set_bit(EFI_BOOT, &efi.flags);
-	else
-		clear_bit(EFI_BOOT, &efi.flags);
 }
 
 static void __init find_tokens(const struct dmi_header *dm, void *dummy)

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

drivers/firmware/efi/Kconfig

@@ -107,7 +107,7 @@ 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
@@ -124,7 +124,7 @@ config EFI_GENERIC_STUB_INITRD_CMDLINE_LOADER
 	bool "Enable the command line initrd loader" if !X86
 	depends on EFI_STUB && (EFI_GENERIC_STUB || X86)
 	default y if X86
-	depends on !RISCV
+	depends on !RISCV && !LOONGARCH
 	help
 	  Select this config option to add support for the initrd= command
 	  line parameter, allowing an initrd that resides on the same volume

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)) \
+				   -fpie
 
 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 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)
 

drivers/firmware/efi/libstub/efi-stub.c

@@ -40,14 +40,22 @@
 
 #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
 
+/*
+ * Some architectures map the EFI regions into the kernel's linear map using a
+ * fixed offset.
+ */
+#ifndef EFI_RT_VIRTUAL_OFFSET
+#define EFI_RT_VIRTUAL_OFFSET	0
+#endif
+
 static u64 virtmap_base = EFI_RT_VIRTUAL_BASE;
-static bool flat_va_mapping;
+static bool flat_va_mapping = (EFI_RT_VIRTUAL_OFFSET != 0);
 
 const efi_system_table_t *efi_system_table;
 
@@ -254,8 +262,8 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
 	 * The easiest way to achieve that is to simply use a 1:1 mapping.
 	 */
 	prop_tbl = get_efi_config_table(EFI_PROPERTIES_TABLE_GUID);
-	flat_va_mapping = prop_tbl &&
-			  (prop_tbl->memory_protection_attribute &
+	flat_va_mapping |= prop_tbl &&
+			   (prop_tbl->memory_protection_attribute &
 			   EFI_PROPERTIES_RUNTIME_MEMORY_PROTECTION_NON_EXECUTABLE_PE_DATA);
 
 	/* force efi_novamap if SetVirtualAddressMap() is unsupported */
@@ -338,7 +346,7 @@ void efi_get_virtmap(efi_memory_desc_t *memory_map, unsigned long map_size,
 		paddr = in->phys_addr;
 		size = in->num_pages * EFI_PAGE_SIZE;
 
-		in->virt_addr = in->phys_addr;
+		in->virt_addr = in->phys_addr + EFI_RT_VIRTUAL_OFFSET;
 		if (efi_novamap) {
 			continue;
 		}

drivers/firmware/efi/libstub/loongarch-stub.c

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Author: Yun Liu <liuyun@loongson.cn>
+ *         Huacai Chen <chenhuacai@loongson.cn>
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+
+#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;
+
+efi_status_t check_platform_features(void)
+{
+	return EFI_SUCCESS;
+}
+
+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;
+
+	/* Config Direct Mapping */
+	csr_write64(CSR_DMW0_INIT, LOONGARCH_CSR_DMWIN0);
+	csr_write64(CSR_DMW1_INIT, LOONGARCH_CSR_DMWIN1);
+
+	real_kernel_entry = (kernel_entry_t)
+		((unsigned long)&kernel_entry - entrypoint + VMLINUX_LOAD_ADDRESS);
+
+	if (!efi_novamap)
+		real_kernel_entry(true, fdt);
+	else
+		real_kernel_entry(false, fdt);
+}

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