diff options
Diffstat (limited to 'src/arch/i386/boot/boot.c')
| -rw-r--r-- | src/arch/i386/boot/boot.c | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/src/arch/i386/boot/boot.c b/src/arch/i386/boot/boot.c new file mode 100644 index 0000000000..84c71da800 --- /dev/null +++ b/src/arch/i386/boot/boot.c @@ -0,0 +1,182 @@ +#include <console/console.h> +#include <ip_checksum.h> +#include <boot/elf.h> +#include <boot/elf_boot.h> +#include <string.h> + + +#ifndef CMD_LINE +#define CMD_LINE "" +#endif + + + +#define UPSZ(X) ((sizeof(X) + 3) &~3) + +static struct { + Elf_Bhdr hdr; + Elf_Nhdr ft_hdr; + unsigned char ft_desc[UPSZ(FIRMWARE_TYPE)]; + Elf_Nhdr bl_hdr; + unsigned char bl_desc[UPSZ(BOOTLOADER)]; + Elf_Nhdr blv_hdr; + unsigned char blv_desc[UPSZ(BOOTLOADER_VERSION)]; + Elf_Nhdr cmd_hdr; + unsigned char cmd_desc[UPSZ(CMD_LINE)]; +} elf_boot_notes = { + .hdr = { + .b_signature = 0x0E1FB007, + .b_size = sizeof(elf_boot_notes), + .b_checksum = 0, + .b_records = 4, + }, + .ft_hdr = { + .n_namesz = 0, + .n_descsz = sizeof(FIRMWARE_TYPE), + .n_type = EBN_FIRMWARE_TYPE, + }, + .ft_desc = FIRMWARE_TYPE, + .bl_hdr = { + .n_namesz = 0, + .n_descsz = sizeof(BOOTLOADER), + .n_type = EBN_BOOTLOADER_NAME, + }, + .bl_desc = BOOTLOADER, + .blv_hdr = { + .n_namesz = 0, + .n_descsz = sizeof(BOOTLOADER_VERSION), + .n_type = EBN_BOOTLOADER_VERSION, + }, + .blv_desc = BOOTLOADER_VERSION, + .cmd_hdr = { + .n_namesz = 0, + .n_descsz = sizeof(CMD_LINE), + .n_type = EBN_COMMAND_LINE, + }, + .cmd_desc = CMD_LINE, +}; + + +int elf_check_arch(Elf_ehdr *ehdr) +{ + return ( + ((ehdr->e_machine == EM_386) || (ehdr->e_machine == EM_486)) && + (ehdr->e_ident[EI_CLASS] == ELFCLASS32) && + (ehdr->e_ident[EI_DATA] == ELFDATA2LSB) + ); + +} + +void jmp_to_elf_entry(void *entry, unsigned long buffer) +{ + extern unsigned char _ram_seg, _eram_seg; + unsigned long lb_start, lb_size; + unsigned long adjust, adjusted_boot_notes; + unsigned long type; + + elf_boot_notes.hdr.b_checksum = + compute_ip_checksum(&elf_boot_notes, sizeof(elf_boot_notes)); + + type = 0x0E1FB007; + lb_start = (unsigned long)&_ram_seg; + lb_size = (unsigned long)(&_eram_seg - &_ram_seg); + adjust = buffer + lb_size - lb_start; + + adjusted_boot_notes = (unsigned long)&elf_boot_notes; + adjusted_boot_notes += adjust; + + printk_spew("entry = 0x%08lx\n", (unsigned long)entry); + printk_spew("lb_start = 0x%08lx\n", lb_start); + printk_spew("lb_size = 0x%08lx\n", lb_size); + printk_spew("adjust = 0x%08lx\n", adjust); + printk_spew("buffer = 0x%08lx\n", buffer); + printk_spew(" elf_boot_notes = 0x%08lx\n", (unsigned long)&elf_boot_notes); + printk_spew("adjusted_boot_notes = 0x%08lx\n", adjusted_boot_notes); + + /* Jump to kernel */ + __asm__ __volatile__( + " cld \n\t" + /* Save the callee save registers... */ + " pushl %%esi\n\t" + " pushl %%edi\n\t" + " pushl %%ebx\n\t" + /* Save the parameters I was passed */ + " pushl $0\n\t" /* 20 adjust */ + " pushl %0\n\t" /* 16 lb_start */ + " pushl %1\n\t" /* 12 buffer */ + " pushl %2\n\t" /* 8 lb_size */ + " pushl %3\n\t" /* 4 entry */ + " pushl %4\n\t" /* 0 elf_boot_notes */ + /* Compute the adjustment */ + " xorl %%eax, %%eax\n\t" + " subl 16(%%esp), %%eax\n\t" + " addl 12(%%esp), %%eax\n\t" + " addl 8(%%esp), %%eax\n\t" + " movl %%eax, 20(%%esp)\n\t" + /* Place a copy of linuxBIOS in it's new location */ + /* Move ``longs'' the linuxBIOS size is 4 byte aligned */ + " movl 12(%%esp), %%edi\n\t" + " addl 8(%%esp), %%edi\n\t" + " movl 16(%%esp), %%esi\n\t" + " movl 8(%%esp), %%ecx\n\n" + " shrl $2, %%ecx\n\t" + " rep movsl\n\t" + + /* Adjust the stack pointer to point into the new linuxBIOS image */ + " addl 20(%%esp), %%esp\n\t" + /* Adjust the instruction pointer to point into the new linuxBIOS image */ + " movl $1f, %%eax\n\t" + " addl 20(%%esp), %%eax\n\t" + " jmp *%%eax\n\t" + "1: \n\t" + + /* Copy the linuxBIOS bounce buffer over linuxBIOS */ + /* Move ``longs'' the linuxBIOS size is 4 byte aligned */ + " movl 16(%%esp), %%edi\n\t" + " movl 12(%%esp), %%esi\n\t" + " movl 8(%%esp), %%ecx\n\t" + " shrl $2, %%ecx\n\t" + " rep movsl\n\t" + + /* Now jump to the loaded image */ + " movl $0x0E1FB007, %%eax\n\t" + " movl 0(%%esp), %%ebx\n\t" + " call *4(%%esp)\n\t" + + /* The loaded image returned? */ + " cli \n\t" + " cld \n\t" + + /* Copy the saved copy of linuxBIOS where linuxBIOS runs */ + /* Move ``longs'' the linuxBIOS size is 4 byte aligned */ + " movl 16(%%esp), %%edi\n\t" + " movl 12(%%esp), %%esi\n\t" + " addl 8(%%esp), %%esi\n\t" + " movl 8(%%esp), %%ecx\n\t" + " shrl $2, %%ecx\n\t" + " rep movsl\n\t" + + /* Adjust the stack pointer to point into the old linuxBIOS image */ + " subl 20(%%esp), %%esp\n\t" + + /* Adjust the instruction pointer to point into the old linuxBIOS image */ + " movl $1f, %%eax\n\t" + " subl 20(%%esp), %%eax\n\t" + " jmp *%%eax\n\t" + "1: \n\t" + + /* Drop the parameters I was passed */ + " addl $24, %%esp\n\t" + + /* Restore the callee save registers */ + " popl %%ebx\n\t" + " popl %%edi\n\t" + " popl %%esi\n\t" + + :: + "g" (lb_start), "g" (buffer), "g" (lb_size), + "g" (entry), "g"(adjusted_boot_notes) + ); +} + + |