Subject: [PATCH] x86, boot: add fields to support load bzImage and ramdisk above 4G ext_ramdisk_image/size will record high 32bits for ramdisk info. xloadflags bit0 will be set if relocatable with 64bit. Let get_ramdisk_image/size to use ext_ramdisk_image/size to get right positon for ramdisk. bootloader will fill value to ext_ramdisk_image/size when it load ramdisk above 4G. Also bootloader will check if xloadflags bit0 is set to decicde if it could load ramdisk high above 4G. Update header version to 2.12. -v2: add ext_cmd_line_ptr for above 4G support. -v3: update to xloadflags from HPA. -v4: use fields from bootparam instead setup_header accoring to HPA. Signed-off-by: Yinghai Lu Cc: Rob Landley Cc: Matt Fleming --- Documentation/x86/boot.txt | 19 ++++++++++++++++++- Documentation/x86/zero-page.txt | 3 +++ arch/x86/boot/compressed/cmdline.c | 3 +++ arch/x86/boot/header.S | 12 ++++++++++-- arch/x86/include/asm/bootparam.h | 10 ++++++++-- arch/x86/kernel/head64.c | 3 +++ arch/x86/kernel/setup.c | 6 ++++++ 7 files changed, 51 insertions(+), 5 deletions(-) Index: linux-2.6/Documentation/x86/boot.txt =================================================================== --- linux-2.6.orig/Documentation/x86/boot.txt +++ linux-2.6/Documentation/x86/boot.txt @@ -57,6 +57,9 @@ Protocol 2.10: (Kernel 2.6.31) Added a p Protocol 2.11: (Kernel 3.6) Added a field for offset of EFI handover protocol entry point. +Protocol 2.12: (Kernel 3.9) Added three fields for loading bzImage and + ramdisk above 4G with 64bit in bootparam. + **** MEMORY LAYOUT The traditional memory map for the kernel loader, used for Image or @@ -182,7 +185,7 @@ Offset Proto Name Meaning 0230/4 2.05+ kernel_alignment Physical addr alignment required for kernel 0234/1 2.05+ relocatable_kernel Whether kernel is relocatable or not 0235/1 2.10+ min_alignment Minimum alignment, as a power of two -0236/2 N/A pad3 Unused +0236/2 2.12+ xloadflags Boot protocol option flags 0238/4 2.06+ cmdline_size Maximum size of the kernel command line 023C/4 2.07+ hardware_subarch Hardware subarchitecture 0240/8 2.07+ hardware_subarch_data Subarchitecture-specific data @@ -581,6 +584,20 @@ Protocol: 2.10+ misaligned kernel. Therefore, a loader should typically try each power-of-two alignment from kernel_alignment down to this alignment. +Field name: xloadflags +Type: modify (obligatory) +Offset/size: 0x236/2 +Protocol: 2.12+ + + This field is a bitmask. + + Bit 0 (read): CAN_BE_LOADED_ABOVE_4G + - If 1, kernel/boot_params/cmdline/ramdisk can be above 4g, + + Bit 15 (write): USE_EXT_BOOT_PARAMS + - If 1, set by bootloader, and kernel could check new fields + in boot_params that are added from 2.12 safely. + Field name: cmdline_size Type: read Offset/size: 0x238/4 Index: linux-2.6/arch/x86/boot/header.S =================================================================== --- linux-2.6.orig/arch/x86/boot/header.S +++ linux-2.6/arch/x86/boot/header.S @@ -279,7 +279,7 @@ _start: # Part 2 of the header, from the old setup.S .ascii "HdrS" # header signature - .word 0x020b # header version number (>= 0x0105) + .word 0x020c # header version number (>= 0x0105) # or else old loadlin-1.5 will fail) .globl realmode_swtch realmode_swtch: .word 0, 0 # default_switch, SETUPSEG @@ -369,7 +369,15 @@ relocatable_kernel: .byte 1 relocatable_kernel: .byte 0 #endif min_alignment: .byte MIN_KERNEL_ALIGN_LG2 # minimum alignment -pad3: .word 0 + +xloadflags: +CAN_BE_LOADED_ABOVE_4G = 1 # If set, the kernel/boot_param/ + # ramdisk could be loaded above 4g +#if defined(CONFIG_X86_64) && defined(CONFIG_RELOCATABLE) + .word CAN_BE_LOADED_ABOVE_4G +#else + .word 0 +#endif cmdline_size: .long COMMAND_LINE_SIZE-1 #length of the command line, #added with boot protocol Index: linux-2.6/arch/x86/include/asm/bootparam.h =================================================================== --- linux-2.6.orig/arch/x86/include/asm/bootparam.h +++ linux-2.6/arch/x86/include/asm/bootparam.h @@ -57,7 +57,10 @@ struct setup_header { __u32 initrd_addr_max; __u32 kernel_alignment; __u8 relocatable_kernel; - __u8 _pad2[3]; + __u8 min_alignment; + __u16 xloadflags; +#define CAN_BE_LOADED_ABOVE_4G (1<<0) +#define USE_EXT_BOOT_PARAMS (1<<15) __u32 cmdline_size; __u32 hardware_subarch; __u64 hardware_subarch_data; @@ -105,7 +108,10 @@ struct boot_params { __u8 hd1_info[16]; /* obsolete! */ /* 0x090 */ struct sys_desc_table sys_desc_table; /* 0x0a0 */ struct olpc_ofw_header olpc_ofw_header; /* 0x0b0 */ - __u8 _pad4[128]; /* 0x0c0 */ + __u32 ext_ramdisk_image; /* 0x0c0 */ + __u32 ext_ramdisk_size; /* 0x0c4 */ + __u32 ext_cmd_line_ptr; /* 0x0c8 */ + __u8 _pad4[116]; /* 0x0cc */ struct edid_info edid_info; /* 0x140 */ struct efi_info efi_info; /* 0x1c0 */ __u32 alt_mem_k; /* 0x1e0 */ Index: linux-2.6/arch/x86/kernel/setup.c =================================================================== --- linux-2.6.orig/arch/x86/kernel/setup.c +++ linux-2.6/arch/x86/kernel/setup.c @@ -302,12 +302,18 @@ static u64 __init get_ramdisk_image(void { u64 ramdisk_image = boot_params.hdr.ramdisk_image; + if (boot_params.hdr.xloadflags & USE_EXT_BOOT_PARAMS) + ramdisk_image |= (u64)boot_params.ext_ramdisk_image << 32; + return ramdisk_image; } static u64 __init get_ramdisk_size(void) { u64 ramdisk_size = boot_params.hdr.ramdisk_size; + if (boot_params.hdr.xloadflags & USE_EXT_BOOT_PARAMS) + ramdisk_size |= (u64)boot_params.ext_ramdisk_size << 32; + return ramdisk_size; } Index: linux-2.6/arch/x86/boot/compressed/cmdline.c =================================================================== --- linux-2.6.orig/arch/x86/boot/compressed/cmdline.c +++ linux-2.6/arch/x86/boot/compressed/cmdline.c @@ -17,6 +17,9 @@ static unsigned long get_cmd_line_ptr(vo { unsigned long cmd_line_ptr = real_mode->hdr.cmd_line_ptr; + if (real_mode->hdr.xloadflags & USE_EXT_BOOT_PARAMS) + cmd_line_ptr |= (u64)real_mode->ext_cmd_line_ptr << 32; + return cmd_line_ptr; } int cmdline_find_option(const char *option, char *buffer, int bufsize) Index: linux-2.6/arch/x86/kernel/head64.c =================================================================== --- linux-2.6.orig/arch/x86/kernel/head64.c +++ linux-2.6/arch/x86/kernel/head64.c @@ -45,6 +45,9 @@ static unsigned long get_cmd_line_ptr(vo { unsigned long cmd_line_ptr = boot_params.hdr.cmd_line_ptr; + if (boot_params.hdr.xloadflags & USE_EXT_BOOT_PARAMS) + cmd_line_ptr |= (u64)boot_params.ext_cmd_line_ptr << 32; + return cmd_line_ptr; } Index: linux-2.6/Documentation/x86/zero-page.txt =================================================================== --- linux-2.6.orig/Documentation/x86/zero-page.txt +++ linux-2.6/Documentation/x86/zero-page.txt @@ -19,6 +19,9 @@ Offset Proto Name Meaning 090/010 ALL hd1_info hd1 disk parameter, OBSOLETE!! 0A0/010 ALL sys_desc_table System description table (struct sys_desc_table) 0B0/010 ALL olpc_ofw_header OLPC's OpenFirmware CIF and friends +0C0/004 ALL ext_ramdisk_image ramdisk_image high 32bits +0C4/004 ALL ext_ramdisk_size ramdisk_size high 32bits +0C8/004 ALL ext_cmd_line_ptr cmd_line_ptr high 32bits 140/080 ALL edid_info Video mode setup (struct edid_info) 1C0/020 ALL efi_info EFI 32 information (struct efi_info) 1E0/004 ALL alk_mem_k Alternative mem check, in KB