diff -uNr linux-2.5.7.boot3.build/Documentation/i386/boot.txt linux-2.5.7.boot3.proto/Documentation/i386/boot.txt --- linux-2.5.7.boot3.build/Documentation/i386/boot.txt Sun Mar 10 20:05:16 2002 +++ linux-2.5.7.boot3.proto/Documentation/i386/boot.txt Wed Apr 3 02:06:43 2002 @@ -127,7 +127,18 @@ 0224/2 2.01+ heap_end_ptr Free memory after setup end 0226/2 N/A pad1 Unused 0228/4 2.02+ cmd_line_ptr 32-bit pointer to the kernel command line -022C/4 2.03+ initrd_addr_max Highest legal initrd address +022C/4 2.03+ ramdisk_max Highest legal initrd address +0230/2 2.04+ entry32_off offset of 32bit entry point +0230/2 2.04+ internal_cmdline_off offset of compiled in command line +0234/4 2.04+ low_base 0x1000 +0238/4 2.04+ low_memsz Memory used @ 0x1000 +023C/4 2.04+ low_filesz Precomputed data for 0x1000 +0240/4 2.04+ real_base 0x90000 +0244/4 2.04+ real_memsz Memory used @ 0x90000 +0248/4 2.04+ real_filesz Precomputed data for @ 0x90000 +024C/4 2.04+ high_memsz Memory used @ 0x100000 +0250/4 2.04+ high_base 0x100000 +0254/4 2.04+ high_filesz Amount of file used for the compressed kernel For backwards compatibility, if the setup_sects field contains 0, the real value is 4. @@ -198,7 +209,7 @@ The initrd should typically be located as high in memory as possible, as it may otherwise get overwritten by the early kernel initialization sequence. However, it must never be - located above the address specified in the initrd_addr_max + located above the address specified in the ramdisk_max field. The initrd should be at least 4K page aligned. cmd_line_ptr: @@ -219,6 +230,76 @@ if your ramdisk is exactly 131072 bytes long and this field is 0x37FFFFFF, you can start your ramdisk at 0x37FE0000.) + entry32_off: + The offset of the 32bit entry point from the real mode kernel. + For boot protocols 2.03 or earlier, this field is not present, + and there is no 32bit entry point. + + internal_cmdline_off: + The offset of the null terminated compiled in command line + from the real mode kernel. For boot protocols 2.03 or + earlier this field is not present, and there is no built in + command line. The memory from internal_cmdline_off to + real_filesz is reserved for the compiled in command_line. An + external utility may modify this command line. + + To change the maximum size of the compiled in command line several + variables need to be modified. real_filesz to indicate the + new maximum size. setup_sects to indicate if the number of + sectors needed for the realmode kernel changes. + + A heap is maintained between real_filesz and real_memsz/heap_end_ptr. + Increasing the size of the heap is not a problem, decreasing + it is. So when changing the real_filesz, real_memsz and + heap_end_ptr should also be changed. real_memsz and + heap_end_ptr should always indicate the same maximum except + at runtime when a bootloader may indicate a larger heap is + present. + + low_base, low_memsz, low_filesz, + real_base, real_memsz, real_filesz, + high_base, high_memsz, high_filesz: + Up to this point building a zImage or a bzImage has been a very lossy + process. The introduction of these six variables attempts to + rectify that situation. They document exactly which pieces + of memory, the kernel uses during the boot process, and they + indicate exactly how large the various data segments of the + kernel are. It is now possible to create a lossless + transformation to and from a static ELF executable. + + For a bzImage the low program segment describes the memory + from 4KB - 572KB the kernel decompressors uses as a temorary + buffer. For a zImage the low program segment describes the + memory from 4KB - 572KB where the compressed kernel is loaded. + + For a bzImage the high program segment describes the memory + from 1MB on where the compressed kernel is loaded, where + decompression takes place, where the kernel initially runs, + and where the kernels bss segment is. For a zImage the high + program segment describes the memory from 1MB on where the + kernel is decompressed to, where the kernel initial runs, and + where the kernels bss segment is located. + + The real program segment describes the memory from 572KB + (0x90000) to 640KB (0xa0000) that the real mode kernel uses. + This region may be moved lower in memory if the BIOS has + reserved region for some other purpose. When doing so + the following considerations should be applied. + + For a zImage you may move the real mode kernel now + lower than low_base + low_memsz. + + For a bzImage if you move real_base below (low_base + + low_memsz) the following are the values of the other + variables. + low_memsz -= (low_base + low_memsz) - real_base + high_memsz += (low_base + low_memsz) - real_base + + + With this information it becomes safe to to statically + relocate the real mode kernel as well as dynamically relocate + it. real_base should not be > 0x90000. + **** THE KERNEL COMMAND LINE @@ -247,6 +328,11 @@ The kernel command line *must* be within the memory region covered by setup_move_size, so you may need to adjust this field. + +If the protocol version is 2.04 or higher a compiled in command line +may be present. If this is the case the passed command line is +appended onto the tail of the compiled command line. Assuming +there is room. **** SAMPLE BOOT CONFIGURATION diff -uNr linux-2.5.7.boot3.build/arch/i386/Config.help linux-2.5.7.boot3.proto/arch/i386/Config.help --- linux-2.5.7.boot3.build/arch/i386/Config.help Wed Mar 20 07:18:31 2002 +++ linux-2.5.7.boot3.proto/arch/i386/Config.help Wed Apr 3 02:06:43 2002 @@ -797,6 +797,12 @@ a work-around for a number of buggy BIOSes. Switch this option on if your computer crashes instead of powering off properly. +CONFIG_CMDLINE + Generally it is best to pass command line parameters via the + bootloader but there are times it is convinient not to do this. + This allows you to hard code a default kernel command line, whatever + the bootloader passes will be appended to it. + CONFIG_TOSHIBA This adds a driver to safely access the System Management Mode of the CPU on Toshiba portables with a genuine Toshiba BIOS. It does diff -uNr linux-2.5.7.boot3.build/arch/i386/boot/realmode.lds linux-2.5.7.boot3.proto/arch/i386/boot/realmode.lds --- linux-2.5.7.boot3.build/arch/i386/boot/realmode.lds Tue Apr 2 22:26:28 2002 +++ linux-2.5.7.boot3.proto/arch/i386/boot/realmode.lds Wed Apr 3 02:06:43 2002 @@ -1,5 +1,5 @@ OUTPUT_FORMAT("elf32-i386", "elf32-i386", "elf32-i386") -ENTRY(_start) +ENTRY(entry32) OUTPUT_ARCH(i386) SECTIONS { diff -uNr linux-2.5.7.boot3.build/arch/i386/boot/setup.S linux-2.5.7.boot3.proto/arch/i386/boot/setup.S --- linux-2.5.7.boot3.build/arch/i386/boot/setup.S Tue Apr 2 22:26:28 2002 +++ linux-2.5.7.boot3.proto/arch/i386/boot/setup.S Wed Apr 3 02:06:43 2002 @@ -42,6 +42,12 @@ * if CX/DX have been changed in the e801 call and if so use AX/BX . * Michael Miller, April 2001 * + * Update boot protocol to version 2.04 + * - Add support for a compiled in command line. + * - Add support for a 32bit kernel entry point + * - Stop information loss when bzImage is created + * Eric Biederman 29 March 2002 + * */ #include @@ -89,7 +95,7 @@ # This is the setup header, and it must start at %cs:2 (old 0x9020:2) .ascii "HdrS" # header signature - .word 0x0203 # header version number (>= 0x0105) + .word 0x0204 # header version number (>= 0x0105) # or else old loadlin-1.5 will fail) realmode_swtch: .word 0, 0 # default_switch, SETUPSEG start_sys_seg: # pointing to kernel version string @@ -164,8 +170,14 @@ # The highest safe address for # the contents of an initrd -# variables private to setup.S (not for bootloaders) -pad2: .long 0 +entry32_off: .word entry32 - start + (DELTA_INITSEG << 4) + # offset of the 32bit entry point + # relative to the start of + # the real mode kernel + +internal_cmdline_off: # offset of compiled in command line + .word internal_command_line - start + (DELTA_INITSEG << 4) + low_base: .long LOW_BASE # low buffer base 0x1000 low_memsz: .long 0x00000000 # Size of low buffer @ 0x1000 low_filesz: .long 0x00000000 # Size of precomputed data @ 0x1000 @@ -177,6 +189,17 @@ high_base: .long HIGH_BASE # high buffer base 0x100000 high_memsz: .long 0x00000000 # Size of high buffer @ 0x100000 high_filesz: .long 0x00000000 # Datasize of the linux kernel +# variables private to the kernel (not for bootloaders) +entry32_used: .long 0x00000000 +entry32_16_off: .long protected_to_real - start + (DELTA_INITSEG << 4) +eax: .long 0x00000000 +ebx: .long 0x00000000 +ecx: .long 0x00000000 +edx: .long 0x00000000 +esi: .long 0x00000000 +edi: .long 0x00000000 +esp: .long 0x00000000 +ebp: .long 0x00000000 trampoline: call start_of_setup # Don't let the E820 map overlap code . = (0x2d0 - 0x200) + (E820MAX * E820ENTRY_SIZE) @@ -1019,29 +1042,174 @@ outb %al,$0x80 ret + .code32 + .globl entry32 +entry32: + testl %esp, %esp + jnz 1f + /* If there isn't a valid stack pointer + * Assume setup.S is loaded at INITSEG, + * and setup a stack pointer just below that. + */ + movl %esp, ((INITSEG << 4) - 4) + movl $((INITSEG << 4) - 4), %esp + jmp 2f +1: pushl %esp +2: pushl %esi + call 3f +3: popl %esi + subl $(3b - start), %esi + movl %eax, eax - start(%esi) + movl %ebx, ebx - start(%esi) + movl %ebx, ebx - start(%esi) + movl %ecx, ecx - start(%esi) + movl %edx, edx - start(%esi) + popl %eax + movl %eax, esi - start(%esi) + movl %edi, edi - start(%esi) + movl %ebp, ebp - start(%esi) + popl %esp + movl %esp, esp - start(%esi) + + /* Magic to indicate 32bit entry */ + movl $ENTRY32, %ebp + movl %ebp, entry32_used - start(%esi) + + /* Pointer to real mode code */ + subl $(DELTA_INITSEG << 4), %esi + + /* Start address for 32-bit code */ + movl $KERNEL_START, %ebx + jmpl *%ebx + +protected_to_real: + cli + /* Get pointer to start */ + call 1f +1: popl %esi + subl $(1b - start), %esi + + /* Fixup my real mode segment */ + movl %esi, %eax + shrl $4, %eax + movw %ax, 2 + realptr - start(%esi) + + /* Compute the gdt fixup */ + movl %esi, %eax + shll $16, %eax # Base low + + movl %esi, %ebx + shrl $16, %ebx + andl $0xff, %ebx + + movl %esi, %edx + andl $0xff000000, %edx + orl %edx, %ebx # Base high + + /* Fixup the gdt */ + andl $0x0000ffff, (gdt - start + __SETUP_REAL_CS)(%esi) + orl %eax, (gdt - start + __SETUP_REAL_CS)(%esi) + andl $0x00ffff00, (gdt - start + __SETUP_REAL_CS + 4)(%esi) + orl %ebx, (gdt - start + __SETUP_REAL_CS + 4)(%esi) + andl $0x0000ffff, (gdt - start + __SETUP_REAL_DS)(%esi) + orl %eax, (gdt - start + __SETUP_REAL_DS)(%esi) + andl $0x00ffff00, (gdt - start + __SETUP_REAL_DS + 4)(%esi) + orl %ebx, (gdt - start + __SETUP_REAL_DS + 4)(%esi) + + /* Fixup gdt_48 */ + leal gdt - start(%esi), %eax # Compute gdt_base + movl %eax, gdt_48 +2 - start(%esi) # Store gdt_base + + /* Setup the classic BIOS interrupt table at 0x0 */ + lidt idt_real - start(%esi) + + /* Load 16bit segments we can use */ + lgdt gdt_48 - start(%esi) + + /* Don't disable the a20 line, (this shouldn't be required) */ + + /* Load 16bit data segments, to ensure the segment limits are set */ + movl $__SETUP_REAL_DS, %ebx + movl %ebx, %ds + movl %ebx, %es + movl %ebx, %ss + movl %ebx, %fs + movl %ebx, %gs + + /* switch to 16bit mode */ + ljmp $__SETUP_REAL_CS, $1f - start +1: + .code16 + /* Disable Paging and protected mode */ + /* clear the PG & PE bits of CR0 */ + movl %cr0,%eax + andl $~((1 << 31)|(1<<0)),%eax + movl %eax,%cr0 + + /* make intersegment jmp to flush the processor pipeline + * and reload %cs:%eip (to clear upper 16 bits of %eip). + */ + ljmp *(realptr - start) +2: + /* we are in real mode now + * set up the real mode segment registers : %ds, %ss, %es, %gs, %fs + */ + movw %cs, %ax + /* Put the data segments in INITSEG */ + subw $DELTA_INITSEG, %ax + movw %ax, %ds + movw %ax, %es + movw %ax, %fs + movw %ax, %gs + /* Put ss:sp just below INITSEG */ + subw $0x800, %ax + movw %ax, %ss + movw $0x8000, %sp + jmp start + +realptr: + .word 2b - start + .word 0x0000 + # Descriptor tables gdt: .word 0, 0, 0, 0 # dummy .word 0, 0, 0, 0 # unused - .word 0xFFFF # 4Gb - (0x100000*0x1000 = 4Gb) + .word 0xFFFF # 32bit 4GB - (0x100000*0x1000 = 4GB) .word 0 # base address = 0 - .word 0x9A00 # code read/exec - .word 0x00CF # granularity = 4096, 386 + .byte 0x00, 0x9B # code read/exec/accessed + .byte 0xCF, 0x00 # granularity = 4096, 386 # (+5th nibble of limit) - .word 0xFFFF # 4Gb - (0x100000*0x1000 = 4Gb) + .word 0xFFFF # 32bit 4GB - (0x100000*0x1000 = 4GB) .word 0 # base address = 0 - .word 0x9200 # data read/write - .word 0x00CF # granularity = 4096, 386 + .byte 0x00, 0x93 # data read/write/accessed + .byte 0xCF, 0x00 # granularity = 4096, 386 # (+5th nibble of limit) + + .word 0xFFFF # 16bit 64KB - (0x10000*1 = 64KB) + .word 0 # base address = SETUPSEG + .byte 0x00, 0x9b # code read/exec/accessed + .byte 0x00, 0x00 # granularity = bytes + + + .word 0xFFFF # 16bit 64KB - (0x10000*1 = 64KB) + .word 0 # base address = SETUPSEG + .byte 0x00, 0x93 # data read/write/accessed + .byte 0x00, 0x00 # granularity = bytes +gdt_end: + idt_48: .word 0 # idt limit = 0 .word 0, 0 # idt base = 0L -gdt_48: - .word 0x8000 # gdt limit=2048, - # 256 GDT entries +idt_real: + .word 0x400 - 1 # idt limit ( 256 entries) + .word 0, 0 # idt base = 0L + +gdt_48: + .word gdt_end - gdt - 1 # gdt limit .word 0, 0 # gdt base (filled in later) # Include video setup & detection code @@ -1054,7 +1222,8 @@ # After this point, there is some free space which is used by the video mode # handling code to store the temporary mode table (not used by the kernel). - +internal_command_line: + .asciz CONFIG_CMDLINE _esetup: .section ".setup.heap", "a", @nobits _setup_heap: diff -uNr linux-2.5.7.boot3.build/arch/i386/config.in linux-2.5.7.boot3.proto/arch/i386/config.in --- linux-2.5.7.boot3.build/arch/i386/config.in Wed Mar 20 07:18:31 2002 +++ linux-2.5.7.boot3.proto/arch/i386/config.in Wed Apr 3 02:06:43 2002 @@ -279,6 +279,7 @@ bool ' Use real mode APM BIOS call to power off' CONFIG_APM_REAL_MODE_POWER_OFF fi +string 'Initial kernel command line' CONFIG_CMDLINE "" endmenu source drivers/mtd/Config.in diff -uNr linux-2.5.7.boot3.build/arch/i386/kernel/setup.c linux-2.5.7.boot3.proto/arch/i386/kernel/setup.c --- linux-2.5.7.boot3.build/arch/i386/kernel/setup.c Tue Apr 2 11:46:18 2002 +++ linux-2.5.7.boot3.proto/arch/i386/kernel/setup.c Wed Apr 3 02:06:43 2002 @@ -101,6 +101,7 @@ #include #include #include +#include #include #include #include @@ -665,34 +666,31 @@ screen_info.orig_video_points = 16; } -static void read_entry16_params(struct boot_params *params) +static void read_entry32_params(struct boot_params *params) { char *cmdline; + int cmdline_off; /* - * These values are set up by the setup-routine at boot-time + * These values are set a compile time or set by the bootloader */ ROOT_DEV = to_kdev_t(params->root_dev); - drive_info = params->drive_info; - screen_info = params->screen.info; - apm_info.bios = params->apm_bios_info; - if( params->sys_desc_table.length != 0 ) { - MCA_bus = params->sys_desc_table.table[3] &0x2; - machine_id = params->sys_desc_table.table[0]; - machine_submodel_id = params->sys_desc_table.table[1]; - BIOS_revision = params->sys_desc_table.table[2]; - } - aux_device_present = params->aux_device_info; + + if (!params->mount_root_rdonly) + root_mountflags &= ~MS_RDONLY; #ifdef CONFIG_BLK_DEV_RAM rd_image_start = params->ramdisk_flags & RAMDISK_IMAGE_START_MASK; rd_prompt = ((params->ramdisk_flags & RAMDISK_PROMPT_FLAG) != 0); rd_doload = ((params->ramdisk_flags & RAMDISK_LOAD_FLAG) != 0); #endif - setup_memory_region(params); - if (!params->mount_root_rdonly) - root_mountflags &= ~MS_RDONLY; + /* The compiled in command line */ + cmdline = (char *)params; + cmdline += params->internal_cmdline_off; + strncpy(command_line, cmdline, COMMAND_LINE_SIZE); + command_line[COMMAND_LINE_SIZE -1] = '\0'; + /* The bootloader passed command line */ cmdline = ""; if (params->cmd_line_ptr) { /* New command line protocol */ @@ -701,33 +699,73 @@ else if (*((unsigned short *)OLD_CL_MAGIC_ADDR) == OLD_CL_MAGIC) { cmdline = (char *)OLD_CL_BASE + *((unsigned short *)OLD_CL_OFFSET_ADDR); } - memcpy(command_line, cmdline, COMMAND_LINE_SIZE); + cmdline_off = strlen(command_line); + memcpy(command_line + cmdline_off, cmdline, COMMAND_LINE_SIZE - cmdline_off); command_line[COMMAND_LINE_SIZE -1] = '\0'; #ifdef CONFIG_BLK_DEV_INITRD if (params->loader_type && params->initrd_start) { initrd_start = params->initrd_start ? - params->initrd_start + PAGE_OFFSET : 0; + params->initrd_start + PAGE_OFFSET : 0; initrd_end = initrd_start + params->initrd_size; } #endif } + +static void read_entry16_params(struct boot_params *params) +{ + /* + * These values are set up by the setup-routine at boot-time + */ + drive_info = params->drive_info; + screen_info = params->screen.info; + apm_info.bios = params->apm_bios_info; + if( params->sys_desc_table.length != 0 ) { + MCA_bus = params->sys_desc_table.table[3] &0x2; + machine_id = params->sys_desc_table.table[0]; + machine_submodel_id = params->sys_desc_table.table[1]; + BIOS_revision = params->sys_desc_table.table[2]; + } + aux_device_present = params->aux_device_info; + + setup_memory_region(params); +} + static void parse_params(char **cmdline_p) { struct boot_params *params; - int entry16; + int entry16, entry32; params = (struct boot_params *)initial_regs.esi; entry16 = initial_regs.ebp == ENTRY16; + entry32 = (initial_regs.ebp == ENTRY32) && (params->entry32_used); init_settings(); + /* Get compiled in and bootloader parameters */ + if (entry16 || entry32) { + read_entry32_params(params); + } + + /* Get parameters from the 16bit BIOS */ if (entry16) { read_entry16_params(params); } /* Read user specified params */ parse_mem_cmdline(cmdline_p); + + if ((e820.nr_map == 0) && entry32) { + /* If we came in via the 32bit entry point and don't + * have a memory size we need help. + * So go out and come back in the 16bit entry point. + */ + void (*entry32_16)(void); + printk(KERN_INFO "No memory size information so reentering 16bit mode\n"); + entry32_16 = (void (*)(void))(initial_regs.esi + params->entry32_16_off); + unlock_kernel(); + entry32_16(); + } if (e820.nr_map == 0) { panic("Unknown memory size\n"); diff -uNr linux-2.5.7.boot3.build/include/asm-i386/boot_param.h linux-2.5.7.boot3.proto/include/asm-i386/boot_param.h --- linux-2.5.7.boot3.build/include/asm-i386/boot_param.h Tue Apr 2 11:46:18 2002 +++ linux-2.5.7.boot3.proto/include/asm-i386/boot_param.h Wed Apr 3 02:06:43 2002 @@ -76,7 +76,23 @@ __u32 cmd_line_ptr; /* 0x228 */ /* 2.03+ */ __u32 ramdisk_max; /* 0x22c */ - __u8 reserved15[0x2d0 - 0x230]; /* 0x230 */ + /* 2.04+ */ + __u16 entry32_off; /* 0x230 */ + __u16 internal_cmdline_off; /* 0x232 */ + __u32 low_base; /* 0x234 */ + __u32 low_memsz; /* 0x238 */ + __u32 low_filesz; /* 0x23c */ + __u32 real_base; /* 0x240 */ + __u32 real_memsz; /* 0x244 */ + __u32 real_filesz; /* 0x248 */ + __u32 high_base; /* 0x24C */ + __u32 high_memsz; /* 0x250 */ + __u32 high_filesz; /* 0x254 */ + /* entry32 values (for internal kernel use only) */ + __u32 entry32_used; /* 0x258 */ + __u32 entry32_16_off; /* 0x25c */ + struct initial_regs32 regs; /* 0x260 */ + __u8 reserved15[0x2d0 - 0x280]; /* 0x280 */ struct e820entry e820_map[E820MAX]; /* 0x2d0 */ /* 0x550 */ } __attribute__((packed));