--- /dev/null
+/*
+ * Linux/i386 loader
+ * Supports bzImage, zImage and Image format.
+ *
+ * Based on work by Steve Gehlbach.
+ * Portions are taken from mkelfImage.
+ *
+ * 2003-09 by SONE Takeshi
+ */
+
+#include "config.h"
+#include "kernel/kernel.h"
+#include "libopenbios/bindings.h"
+#include "libopenbios/sys_info.h"
+#include "context.h"
+#include "segment.h"
+#include "libc/diskio.h"
+#include "boot.h"
+
+#define printf printk
+#define debug printk
+#define strtoull_with_suffix strtol
+
+#define LINUX_PARAM_LOC 0x90000
+#define COMMAND_LINE_LOC 0x91000
+#define GDT_LOC 0x92000
+#define STACK_LOC 0x93000
+
+#define E820MAX 32 /* number of entries in E820MAP */
+struct e820entry {
+ unsigned long long addr; /* start of memory segment */
+ unsigned long long size; /* size of memory segment */
+ unsigned long type; /* type of memory segment */
+#define E820_RAM 1
+#define E820_RESERVED 2
+#define E820_ACPI 3 /* usable as RAM once ACPI tables have been read */
+#define E820_NVS 4
+};
+
+/* The header of Linux/i386 kernel */
+struct linux_header {
+ uint8_t reserved1[0x1f1]; /* 0x000 */
+ uint8_t setup_sects; /* 0x1f1 */
+ uint16_t root_flags; /* 0x1f2 */
+ uint8_t reserved2[6]; /* 0x1f4 */
+ uint16_t vid_mode; /* 0x1fa */
+ uint16_t root_dev; /* 0x1fc */
+ uint16_t boot_sector_magic; /* 0x1fe */
+ /* 2.00+ */
+ uint8_t reserved3[2]; /* 0x200 */
+ uint8_t header_magic[4]; /* 0x202 */
+ uint16_t protocol_version; /* 0x206 */
+ uint32_t realmode_swtch; /* 0x208 */
+ uint16_t start_sys; /* 0x20c */
+ uint16_t kver_addr; /* 0x20e */
+ uint8_t type_of_loader; /* 0x210 */
+ uint8_t loadflags; /* 0x211 */
+ uint16_t setup_move_size; /* 0x212 */
+ uint32_t code32_start; /* 0x214 */
+ uint32_t ramdisk_image; /* 0x218 */
+ uint32_t ramdisk_size; /* 0x21c */
+ uint8_t reserved4[4]; /* 0x220 */
+ /* 2.01+ */
+ uint16_t heap_end_ptr; /* 0x224 */
+ uint8_t reserved5[2]; /* 0x226 */
+ /* 2.02+ */
+ uint32_t cmd_line_ptr; /* 0x228 */
+ /* 2.03+ */
+ uint32_t initrd_addr_max; /* 0x22c */
+} __attribute__ ((packed));
+
+
+/* Paramters passed to 32-bit part of Linux
+ * This is another view of the structure above.. */
+struct linux_params {
+ uint8_t orig_x; /* 0x00 */
+ uint8_t orig_y; /* 0x01 */
+ uint16_t ext_mem_k; /* 0x02 -- EXT_MEM_K sits here */
+ uint16_t orig_video_page; /* 0x04 */
+ uint8_t orig_video_mode; /* 0x06 */
+ uint8_t orig_video_cols; /* 0x07 */
+ uint16_t unused2; /* 0x08 */
+ uint16_t orig_video_ega_bx; /* 0x0a */
+ uint16_t unused3; /* 0x0c */
+ uint8_t orig_video_lines; /* 0x0e */
+ uint8_t orig_video_isVGA; /* 0x0f */
+ uint16_t orig_video_points; /* 0x10 */
+
+ /* VESA graphic mode -- linear frame buffer */
+ uint16_t lfb_width; /* 0x12 */
+ uint16_t lfb_height; /* 0x14 */
+ uint16_t lfb_depth; /* 0x16 */
+ uint32_t lfb_base; /* 0x18 */
+ uint32_t lfb_size; /* 0x1c */
+ uint16_t cl_magic; /* 0x20 */
+#define CL_MAGIC_VALUE 0xA33F
+ uint16_t cl_offset; /* 0x22 */
+ uint16_t lfb_linelength; /* 0x24 */
+ uint8_t red_size; /* 0x26 */
+ uint8_t red_pos; /* 0x27 */
+ uint8_t green_size; /* 0x28 */
+ uint8_t green_pos; /* 0x29 */
+ uint8_t blue_size; /* 0x2a */
+ uint8_t blue_pos; /* 0x2b */
+ uint8_t rsvd_size; /* 0x2c */
+ uint8_t rsvd_pos; /* 0x2d */
+ uint16_t vesapm_seg; /* 0x2e */
+ uint16_t vesapm_off; /* 0x30 */
+ uint16_t pages; /* 0x32 */
+ uint8_t reserved4[12]; /* 0x34 -- 0x3f reserved for future expansion */
+
+ //struct apm_bios_info apm_bios_info; /* 0x40 */
+ uint8_t apm_bios_info[0x40];
+ //struct drive_info_struct drive_info; /* 0x80 */
+ uint8_t drive_info[0x20];
+ //struct sys_desc_table sys_desc_table; /* 0xa0 */
+ uint8_t sys_desc_table[0x140];
+ uint32_t alt_mem_k; /* 0x1e0 */
+ uint8_t reserved5[4]; /* 0x1e4 */
+ uint8_t e820_map_nr; /* 0x1e8 */
+ uint8_t reserved6[9]; /* 0x1e9 */
+ uint16_t mount_root_rdonly; /* 0x1f2 */
+ uint8_t reserved7[4]; /* 0x1f4 */
+ uint16_t ramdisk_flags; /* 0x1f8 */
+#define RAMDISK_IMAGE_START_MASK 0x07FF
+#define RAMDISK_PROMPT_FLAG 0x8000
+#define RAMDISK_LOAD_FLAG 0x4000
+ uint8_t reserved8[2]; /* 0x1fa */
+ uint16_t orig_root_dev; /* 0x1fc */
+ uint8_t reserved9[1]; /* 0x1fe */
+ uint8_t aux_device_info; /* 0x1ff */
+ uint8_t reserved10[2]; /* 0x200 */
+ uint8_t param_block_signature[4]; /* 0x202 */
+ uint16_t param_block_version; /* 0x206 */
+ uint8_t reserved11[8]; /* 0x208 */
+ uint8_t loader_type; /* 0x210 */
+#define LOADER_TYPE_LOADLIN 1
+#define LOADER_TYPE_BOOTSECT_LOADER 2
+#define LOADER_TYPE_SYSLINUX 3
+#define LOADER_TYPE_ETHERBOOT 4
+#define LOADER_TYPE_KERNEL 5
+ uint8_t loader_flags; /* 0x211 */
+ uint8_t reserved12[2]; /* 0x212 */
+ uint32_t kernel_start; /* 0x214 */
+ uint32_t initrd_start; /* 0x218 */
+ uint32_t initrd_size; /* 0x21c */
+ uint8_t reserved12_5[8]; /* 0x220 */
+ uint32_t cmd_line_ptr; /* 0x228 */
+ uint8_t reserved13[164]; /* 0x22c */
+ struct e820entry e820_map[E820MAX]; /* 0x2d0 */
+ uint8_t reserved16[688]; /* 0x550 */
+#define COMMAND_LINE_SIZE 256
+ /* Command line is copied here by 32-bit i386/kernel/head.S.
+ * So I will follow the boot protocol, rather than putting it
+ * directly here. --ts1 */
+ uint8_t command_line[COMMAND_LINE_SIZE]; /* 0x800 */
+ uint8_t reserved17[1792]; /* 0x900 - 0x1000 */
+};
+
+static uint64_t forced_memsize;
+static int fd;
+
+static unsigned long file_size(void)
+{
+ long long fpos, fsize;
+
+ /* Save current position */
+ fpos = tell(fd);
+
+ /* Go to end of file and get position */
+ seek_io(fd, -1);
+ fsize = tell(fd);
+
+ /* Go back to old position */
+ seek_io(fd, 0);
+ seek_io(fd, fpos);
+
+ return fsize;
+}
+
+/* Load the first part the file and check if it's Linux */
+static uint32_t load_linux_header(struct linux_header *hdr)
+{
+ int load_high;
+ uint32_t kern_addr;
+
+ if (read_io(fd, hdr, sizeof *hdr) != sizeof *hdr) {
+ debug("Can't read Linux header\n");
+ return 0;
+ }
+ if (hdr->boot_sector_magic != 0xaa55) {
+ debug("Not a Linux kernel image\n");
+ return 0;
+ }
+
+ /* Linux is found. Print some information */
+ if (memcmp(hdr->header_magic, "HdrS", 4) != 0) {
+ /* This may be floppy disk image or something.
+ * Perform a simple (incomplete) sanity check. */
+ if (hdr->setup_sects >= 16
+ || file_size() - (hdr->setup_sects<<9) >= 512<<10) {
+ debug("This looks like a bootdisk image but not like Linux...\n");
+ return 0;
+ }
+
+ printf("Possible very old Linux");
+ /* This kernel does not even have a protocol version.
+ * Force the value. */
+ hdr->protocol_version = 0; /* pre-2.00 */
+ } else
+ printf("Found Linux");
+ if (hdr->protocol_version >= 0x200 && hdr->kver_addr) {
+ char kver[256];
+ seek_io(fd, hdr->kver_addr + 0x200);
+ if (read_io(fd, kver, sizeof kver) != 0) {
+ kver[255] = 0;
+ printf(" version %s", kver);
+ }
+ }
+ debug(" (protocol %#x)", hdr->protocol_version);
+ load_high = 0;
+ if (hdr->protocol_version >= 0x200) {
+ debug(" (loadflags %#x)", hdr->loadflags);
+ load_high = hdr->loadflags & 1;
+ }
+ if (load_high) {
+ printf(" bzImage");
+ kern_addr = 0x100000;
+ } else {
+ printf(" zImage or Image");
+ kern_addr = 0x1000;
+ }
+ printf(".\n");
+
+ return kern_addr;
+}
+
+/* Set up parameters for 32-bit kernel */
+static void
+init_linux_params(struct linux_params *params, struct linux_header *hdr)
+{
+ debug("Setting up paramters at %#lx\n", virt_to_phys(params));
+ memset(params, 0, sizeof *params);
+
+ /* Copy some useful values from header */
+ params->mount_root_rdonly = hdr->root_flags;
+ params->orig_root_dev = hdr->root_dev;
+
+ /* Video parameters.
+ * This assumes we have VGA in standard 80x25 text mode,
+ * just like our vga.c does.
+ * Cursor position is filled later to allow some more printf's. */
+ params->orig_video_mode = 3;
+ params->orig_video_cols = 80;
+ params->orig_video_lines = 25;
+ params->orig_video_isVGA = 1;
+ params->orig_video_points = 16;
+
+ params->loader_type = 0xff; /* Unregistered Linux loader */
+}
+
+/* Memory map */
+static void
+set_memory_size(struct linux_params *params, struct sys_info *info)
+{
+ int i;
+ uint64_t end;
+ uint32_t ramtop = 0;
+ struct e820entry *linux_map;
+ struct memrange *filo_map;
+
+ linux_map = params->e820_map;
+ filo_map = info->memrange;
+ for (i = 0; i < info->n_memranges; i++, linux_map++, filo_map++) {
+ if (i < E820MAX) {
+ /* Convert to BIOS e820 style */
+ linux_map->addr = filo_map->base;
+ linux_map->size = filo_map->size;
+ linux_map->type = E820_RAM;
+ debug("%016Lx - %016Lx\n", linux_map->addr,
+ linux_map->addr + linux_map->size);
+ params->e820_map_nr = i+1;
+ }
+
+ /* Find out top of RAM. XXX This ignores hole above 1MB */
+ end = filo_map->base + filo_map->size;
+ if (end < (1ULL << 32)) { /* don't count memory above 4GB */
+ if (end > ramtop)
+ ramtop = (uint32_t) end;
+ }
+ }
+ debug("ramtop=%#x\n", ramtop);
+ /* Size of memory above 1MB in KB */
+ params->alt_mem_k = (ramtop - (1<<20)) >> 10;
+ /* old style, 64MB max */
+ if (ramtop >= (64<<20))
+ params->ext_mem_k = (63<<10);
+ else
+ params->ext_mem_k = params->alt_mem_k;
+ debug("ext_mem_k=%d, alt_mem_k=%d\n", params->ext_mem_k, params->alt_mem_k);
+}
+
+/*
+ * Parse command line
+ * Some parameters, like initrd=<file>, are not passed to kernel,
+ * we are responsible to process them.
+ * Parameters for kernel are copied to kern_cmdline. Returns name of initrd.
+ */
+static char *parse_command_line(const char *orig_cmdline, char *kern_cmdline)
+{
+ const char *start, *sep, *end, *val;
+ char name[64];
+ int len;
+ int k_len;
+ int to_kern;
+ char *initrd = NULL;
+ int toolong = 0;
+
+ forced_memsize = 0;
+
+ if (!orig_cmdline) {
+ *kern_cmdline = 0;
+ return NULL;
+ }
+
+ k_len = 0;
+ debug("original command line: \"%s\"\n", orig_cmdline);
+ debug("kernel command line at %#lx\n", virt_to_phys(kern_cmdline));
+
+ start = orig_cmdline;
+ while (*start == ' ')
+ start++;
+ while (*start) {
+ end = strchr(start, ' ');
+ if (!end)
+ end = start + strlen(start);
+ sep = strchr(start, '=');
+ if (!sep || sep > end)
+ sep = end;
+ len = sep - start;
+ if (len >= sizeof(name))
+ len = sizeof(name) - 1;
+ memcpy(name, start, len);
+ name[len] = 0;
+
+ if (*sep == '=') {
+ val = sep + 1;
+ len = end - val;
+ } else {
+ val = NULL;
+ len = 0;
+ }
+
+ /* Only initrd= and mem= are handled here. vga= is not,
+ * which I believe is a paramter to the realmode part of Linux,
+ * which we don't execute. */
+ if (strcmp(name, "initrd") == 0) {
+ if (!val)
+ printf("Missing filename to initrd parameter\n");
+ else {
+ initrd = malloc(len + 1);
+ memcpy(initrd, val, len);
+ initrd[len] = 0;
+ debug("initrd=%s\n", initrd);
+ }
+ /* Don't pass this to kernel */
+ to_kern = 0;
+ } else if (strcmp(name, "mem") == 0) {
+ if (!val)
+ printf("Missing value for mem parameter\n");
+ else {
+ forced_memsize = strtoull_with_suffix(val, (char**)&val, 0);
+ if (forced_memsize == 0)
+ printf("Invalid mem option, ignored\n");
+ if (val != end) {
+ printf("Garbage after mem=<size>, ignored\n");
+ forced_memsize = 0;
+ }
+ debug("mem=%Lu\n", forced_memsize);
+ }
+ /* mem= is for both loader and kernel */
+ to_kern = 1;
+ } else
+ to_kern = 1;
+
+ if (to_kern) {
+ /* Copy to kernel command line buffer */
+ if (k_len != 0)
+ kern_cmdline[k_len++] = ' '; /* put separator */
+ len = end - start;
+ if (k_len + len >= COMMAND_LINE_SIZE) {
+ len = COMMAND_LINE_SIZE - k_len - 1;
+ if (!toolong) {
+ printf("Kernel command line is too long; truncated to "
+ "%d bytes\n", COMMAND_LINE_SIZE-1);
+ toolong = 1;
+ }
+ }
+ memcpy(kern_cmdline + k_len, start, len);
+ k_len += len;
+ }
+
+ start = end;
+ while (*start == ' ')
+ start++;
+ }
+ kern_cmdline[k_len] = 0;
+ debug("kernel command line (%d bytes): \"%s\"\n", k_len, kern_cmdline);
+
+ return initrd;
+}
+
+/* Set command line location */
+static void set_command_line_loc(struct linux_params *params,
+ struct linux_header *hdr)
+{
+ if (hdr->protocol_version >= 0x202) {
+ /* new style */
+ params->cmd_line_ptr = COMMAND_LINE_LOC;
+ } else {
+ /* old style */
+ params->cl_magic = CL_MAGIC_VALUE;
+ params->cl_offset = COMMAND_LINE_LOC - LINUX_PARAM_LOC;
+ }
+}
+
+/* Load 32-bit part of kernel */
+static int load_linux_kernel(struct linux_header *hdr, uint32_t kern_addr)
+{
+ uint32_t kern_offset, kern_size;
+
+ if (hdr->setup_sects == 0)
+ hdr->setup_sects = 4;
+ kern_offset = (hdr->setup_sects + 1) * 512;
+ seek_io(fd, kern_offset);
+ kern_size = file_size() - kern_offset;
+ debug("offset=%#x addr=%#x size=%#x\n", kern_offset, kern_addr, kern_size);
+
+#if 0
+ if (using_devsize) {
+ printf("Attempt to load up to end of device as kernel; "
+ "specify the image size\n");
+ return 0;
+ }
+#endif
+
+ printf("Loading kernel... ");
+ if (read_io(fd, phys_to_virt(kern_addr), kern_size) != kern_size) {
+ printf("Can't read kernel\n");
+ return 0;
+ }
+ printf("ok\n");
+
+ return kern_size;
+}
+
+static int load_initrd(struct linux_header *hdr, struct sys_info *info,
+ uint32_t kern_end, struct linux_params *params, const char *initrd_file)
+{
+ uint32_t max;
+ uint32_t start, end, size;
+ uint64_t forced;
+
+ fd = open_io(initrd_file);
+ if (fd == -1) {
+ printf("Can't open initrd: %s\n", initrd_file);
+ return -1;
+ }
+
+#if 0
+ if (using_devsize) {
+ printf("Attempt to load up to end of device as initrd; "
+ "specify the image size\n");
+ return -1;
+ }
+#endif
+
+ size = file_size();
+
+
+ /* Find out the kernel's restriction on how high the initrd can be
+ * placed */
+ if (hdr->protocol_version >= 0x203)
+ max = hdr->initrd_addr_max;
+ else
+ max = 0x38000000; /* Hardcoded value for older kernels */
+
+ /* FILO itself is at the top of RAM. (relocated)
+ * So, try putting initrd just below us. */
+ end = virt_to_phys(_start);
+ if (end > max)
+ end = max;
+
+ /* If "mem=" option is given, we have to put the initrd within
+ * the specified range. */
+ if (forced_memsize) {
+ forced = forced_memsize;
+ if (forced > max)
+ forced = max;
+ /* If the "mem=" is lower, it's easy */
+ if (forced <= end)
+ end = forced;
+ else {
+ /* Otherwise, see if we can put it above us */
+ if (virt_to_phys(_end) + size <= forced)
+ end = forced; /* Ok */
+ }
+ }
+
+ start = end - size;
+ start &= ~0xfff; /* page align */
+ end = start + size;
+
+ debug("start=%#x end=%#x\n", start, end);
+
+ if (start < kern_end) {
+ printf("Initrd is too big to fit in memory\n");
+ return -1;
+ }
+
+ printf("Loading initrd... ");
+ if (read_io(fd, phys_to_virt(start), size) != size) {
+ printf("Can't read initrd\n");
+ return -1;
+ }
+ printf("ok\n");
+
+ params->initrd_start = start;
+ params->initrd_size = size;
+
+ close_io(fd);
+
+ return 0;
+}
+
+static void hardware_setup(void)
+{
+ /* Disable nmi */
+ outb(0x80, 0x70);
+
+ /* Make sure any coprocessor is properly reset.. */
+ outb(0, 0xf0);
+ outb(0, 0xf1);
+
+ /* we're getting screwed again and again by this problem of the 8259.
+ * so we're going to leave this lying around for inclusion into
+ * crt0.S on an as-needed basis.
+ *
+ * well, that went ok, I hope. Now we have to reprogram the interrupts :-(
+ * we put them right after the intel-reserved hardware interrupts, at
+ * int 0x20-0x2F. There they won't mess up anything. Sadly IBM really
+ * messed this up with the original PC, and they haven't been able to
+ * rectify it afterwards. Thus the bios puts interrupts at 0x08-0x0f,
+ * which is used for the internal hardware interrupts as well. We just
+ * have to reprogram the 8259's, and it isn't fun.
+ */
+
+ outb(0x11, 0x20); /* initialization sequence to 8259A-1 */
+ outb(0x11, 0xA0); /* and to 8259A-2 */
+
+ outb(0x20, 0x21); /* start of hardware int's (0x20) */
+ outb(0x28, 0xA1); /* start of hardware int's 2 (0x28) */
+
+ outb(0x04, 0x21); /* 8259-1 is master */
+ outb(0x02, 0xA1); /* 8259-2 is slave */
+
+ outb(0x01, 0x21); /* 8086 mode for both */
+ outb(0x01, 0xA1);
+
+ outb(0xFF, 0xA1); /* mask off all interrupts for now */
+ outb(0xFB, 0x21); /* mask all irq's but irq2 which is cascaded */
+}
+
+/* Start Linux */
+static int start_linux(uint32_t kern_addr, struct linux_params *params)
+{
+ struct segment_desc *linux_gdt;
+ struct context *ctx;
+ //extern int cursor_x, cursor_y;
+
+ ctx = init_context(phys_to_virt(STACK_LOC), 4096, 0);
+
+ /* Linux expects GDT being in low memory */
+ linux_gdt = phys_to_virt(GDT_LOC);
+ memset(linux_gdt, 0, 13*sizeof(struct segment_desc));
+ /* Normal kernel code/data segments */
+ linux_gdt[2] = gdt[FLAT_CODE];
+ linux_gdt[3] = gdt[FLAT_DATA];
+ /* 2.6 kernel uses 12 and 13, but head.S uses backward-compatible
+ * segments (2 and 3), so it SHOULD not be a problem.
+ * However, some distro kernels (eg. RH9) with backported threading
+ * patch use 12 and 13 also when booting... */
+ linux_gdt[12] = gdt[FLAT_CODE];
+ linux_gdt[13] = gdt[FLAT_DATA];
+ ctx->gdt_base = GDT_LOC;
+ ctx->gdt_limit = 14*8-1;
+ ctx->cs = 0x10;
+ ctx->ds = 0x18;
+ ctx->es = 0x18;
+ ctx->fs = 0x18;
+ ctx->gs = 0x18;
+ ctx->ss = 0x18;
+
+ /* Parameter location */
+ ctx->esi = virt_to_phys(params);
+
+ /* Entry point */
+ ctx->eip = kern_addr;
+
+ debug("eip=%#x\n", kern_addr);
+ printf("Jumping to entry point...\n");
+
+#ifdef VGA_CONSOLE
+ /* Update VGA cursor position.
+ * This must be here because the printf changes the value! */
+ params->orig_x = cursor_x;
+ params->orig_y = cursor_y;
+#endif
+
+ /* Go... */
+ ctx = switch_to(ctx);
+
+ /* It's impossible but... */
+ printf("Returned with eax=%#x\n", ctx->eax);
+
+ return ctx->eax;
+}
+
+int linux_load(struct sys_info *info, const char *file, const char *cmdline)
+{
+ struct linux_header hdr;
+ struct linux_params *params;
+ uint32_t kern_addr, kern_size;
+ char *initrd_file = NULL;
+
+ fd = open_io(file);
+ if (fd == -1) {
+ return -1;
+ }
+
+ kern_addr = load_linux_header(&hdr);
+ if (kern_addr == 0)
+ return LOADER_NOT_SUPPORT;
+
+ params = phys_to_virt(LINUX_PARAM_LOC);
+ init_linux_params(params, &hdr);
+ set_memory_size(params, info);
+ initrd_file = parse_command_line(cmdline, phys_to_virt(COMMAND_LINE_LOC));
+ set_command_line_loc(params, &hdr);
+
+ kern_size = load_linux_kernel(&hdr, kern_addr);
+ if (kern_size == 0) {
+ if (initrd_file)
+ free(initrd_file);
+ return -1;
+ }
+
+ if (initrd_file) {
+ if (load_initrd(&hdr, info, kern_addr+kern_size, params, initrd_file)
+ != 0) {
+ free(initrd_file);
+ return -1;
+ }
+ free(initrd_file);
+ }
+
+ hardware_setup();
+
+ start_linux(kern_addr, params);
+ return 0;
+}
Code Review / kvmfornfv.git / blobdiff