change the format of drive info in the Multiboot Specification, implement some of the new features.

ChangeLog

@@ -1,3 +1,31 @@
+2000-10-16  OKUJI Yoshinori  <okuji@gnu.org>
+
+	Some of the new Multiboot features are supported. APM support
+	and VESA support are not strictly defined or implemented yet.
+	
+	* docs/multiboot.texi (Top): Increase the version number.
+	(Boot information format): Changed the drive information format,
+	because it was not straightforward.
+	
+	* grub/asmstub.c (io_map): New variable.
+	(track_int13): New function.
+	(get_rom_config_table): Likewise.
+	* stage2/stage2.c (cmain): Set CONFIG_ENTRIES to MBI.DRIVES_ADDR
+	+ MBI.DRIVES.LENGTH instead of MBI.MMAP_ADDR + MBI.MMAP_LENGTH.
+	* stage2/common.c (init_bios_info) [!STAGE1_5]: Added support
+	for drive info, ROM config table, and boot loader name features
+	of the Multiboot Specification.
+	* stage2/mb_info.h (drive_info): New structure.
+	(MB_DI_CHS_MODE): New macro.
+	(MB_DI_LBA_MODE): Likewise.
+	(multiboot_info): Added drives_length, drives_addr,
+	config_table, and boot_loader_name.
+	(MB_INFO_DRIVE_INFO): New macro.
+	(MB_INFO_CONFIG_TABLE): Likewise.
+	(MB_INFO_BOOT_LOADER_NAME): Likewise.
+	* stage2/asm.S (get_rom_config_table): New function.
+	* stage2/shared.h (get_rom_config_table): Declared.
+	
 2000-10-16  OKUJI Yoshinori  <okuji@gnu.org>
 
 	* util/grub-install.in (convert): Check only if the file exists,

docs/grub-install.8

@@ -22,8 +22,11 @@ instead of the root directory.
 use FILE as the grub shell.
 .TP
 \fB\-\-force\-lba\fR
-Force GRUB to use LBA mode even for a buggy
+force GRUB to use LBA mode even for a buggy
 BIOS.
+.TP
+\fB\-\-recheck\fR
+probe a device map even if it already exists.
 .PP
 INSTALL_DEVICE can be a GRUB device name or a system device filename.
 .PP

docs/multiboot.texi

@@ -71,7 +71,7 @@ into another language, under the above conditions for modified versions.
 @top Multiboot Specification
 
 This file documents Multiboot Specification, the proposal for the boot
-sequence standard. This edition documents version 0.6.90.
+sequence standard. This edition documents version 0.6.91.
 @end ifnottex
 
 
@@ -567,7 +567,7 @@ follows:
 44      | mmap_length       |    (present if flags[6] is set)
 48      | mmap_addr         |    (present if flags[6] is set)
         +-------------------+
-52      | drives_count      |    (present if flags[7] is set)
+52      | drives_length     |    (present if flags[7] is set)
 56      | drives_addr       |    (present if flags[7] is set)
         +-------------------+
 60      | config_table      |    (present if flags[8] is set)
@@ -765,29 +765,33 @@ be available for normal use.
 
 If bit 7 in the @samp{flags} is set, then the @samp{drives_*} fields
 are valid, and indicate the address of the physical address of the first
-drive structure and the number of drive structures. @samp{drives_addr}
+drive structure and the size of drive structures. @samp{drives_addr}
-is the address, and @samp{drives_count} is the
+is the address, and @samp{drives_length} is the total size of drive
-number. @samp{drives_count} may be zero. Each drive structure is
+structures. Note that @samp{drives_length} may be zero. Each drive
-formatted as follows:
+structure is formatted as follows:
 
 @example
 @group
         +-------------------+
-0       | drive_number      |
+0       | size              |
         +-------------------+
-1       | drive_mode        |
+4       | drive_number      |
         +-------------------+
-2       | drive_cylinders   |
+5       | drive_mode        |
-4       | drive_heads       |
-5       | drive_sectors     |
         +-------------------+
-6       | drive_ports       |
+6       | drive_cylinders   |
+8       | drive_heads       |
+9       | drive_sectors     |
         +-------------------+
-10      | reserved (0)      |
+10 - xx | drive_ports       |
         +-------------------+
 @end group
 @end example
 
+The @samp{size} field specifies the size of this structure. The size
+varies, depending on the number of ports. Note that the size may not be
+equal to (10 + 2 * the number of ports), because of an alignment.
+
 The @samp{drive_number} field contains the BIOS drive number. The
 @samp{drive_mode} field represents the access mode used by the boot
 loader. Currently, the following modes are defined:
@@ -807,15 +811,11 @@ cylinders. @samp{drive_heads} contains the number of the
 heads. @samp{drive_sectors} contains the number of the sectors per
 track.
 
-The @samp{drive_ports} field contains the physical address of the array
+The @samp{drive_ports} field contains the array of the I/O ports used
-of the I/O ports used for the drive in the @sc{bios} code. The array
+for the drive in the @sc{bios} code. The array consists of zero or more
-consists of zero or more unsigned two-bytes integers, and is terminated
+unsigned two-bytes integers, and is terminated with zero. Note that the
-with zero. Note that the array may contain any number of I/O ports that
+array may contain any number of I/O ports that are not related to the
-are not related to the drive actually (such as @sc{dma} controller's
+drive actually (such as @sc{dma} controller's ports).
-ports).
-
-The last field @samp{reserved} is reserved for future use, and must be
-zero. The size is four bytes.
 
 If bit 8 in the @samp{flags} is set, then the @samp{config_table} field
 is valid, and indicates the address of the @sc{rom} configuration table

grub/asmstub.c

@@ -71,6 +71,7 @@ int saved_entryno = 0;
 char version_string[] = VERSION;
 char config_file[128] = "/boot/grub/menu.lst"; /* FIXME: arbitrary */
 unsigned long linux_text_len = 0;
+unsigned short io_map[IO_MAP_SIZE];
 
 /* Emulation requirements. */
 char *grub_scratch_mem = 0;
@@ -423,6 +424,19 @@ get_mmap_entry (struct mmar_desc *desc, int cont)
   return 0;
 }
 
+/* Track the int13 handler.  */
+void
+track_int13 (int drive)
+{
+  /* Nothing to do in the simulator.  */
+}
+
+/* Get the ROM configuration table.  */
+unsigned long
+get_rom_config_table (void)
+{
+  return 0;
+}
 
 /* low-level timing info */
 int

stage2/asm.S

@@ -1596,6 +1596,50 @@ xsmap:
 	pop	%ebp
 	ret
 
+/*
+ * get_rom_config_table()
+ *
+ * Get the linear address of a ROM configuration table. Return zero,
+ * if fails.
+ */
+	
+ENTRY(get_rom_config_table)
+	pushl	%ebp
+	pushl	%ebx
+
+	/* zero %ebx for simplicity */
+	xorl	%ebx, %ebx
+	
+	call	EXT_C(prot_to_real)
+	.code16
+
+	movw	$0xc0, %ax
+	int	$0x15
+
+	jc	no_rom_table
+	testb	%ah, %ah
+	jnz	no_rom_table
+	
+	movw	%es, %dx
+	jmp	found_rom_table
+	
+no_rom_table:
+	xorw	%dx, %dx
+	xorw	%bx, %bx
+	
+found_rom_table:
+	DATA32	call	EXT_C(real_to_prot)
+	.code32
+
+	/* compute the linear address */
+	movw	%dx, %ax
+	shll	$4, %eax
+	addl	%ebx, %eax
+
+	popl	%ebx
+	popl	%ebp
+	ret
+
 /*
  * gateA20(int linear)
  *

stage2/common.c

@@ -158,6 +158,7 @@ init_bios_info (void)
 {
 #ifndef STAGE1_5
   unsigned long cont, memtmp, addr;
+  int drive;
 #endif
 
   /*
@@ -260,11 +261,60 @@ init_bios_info (void)
 
   saved_mem_upper = mbi.mem_upper;
 
+  /* Get the drive info.  */
+  /* FIXME: This should be postponed until a Multiboot kernel actually
+     requires it, because this could slow down the start-up
+     unreasonably.  */
+  mbi.drives_length = 0;
+  mbi.drives_addr = addr;
+
+  /* For now, GRUB doesn't probe floppies, since it is trivial to map
+     floppy drives to BIOS drives.  */
+  for (drive = 0x80; drive < 0x88; drive++)
+    {
+      struct geometry geom;
+      struct drive_info *info = (struct drive_info *) addr;
+      unsigned short *port;
+      
+      /* Get the geometry. This ensures that the drive is present.  */
+      if (get_diskinfo (drive, &geom))
+	break;
+      
+      /* Clean out the I/O map.  */
+      grub_memset ((char *) io_map, 0,
+		   IO_MAP_SIZE * sizeof (unsigned short));
+      /* Track the int13 handler.  */
+      track_int13 (drive);
+
+      /* Set the information.  */
+      info->drive_number = drive;
+      info->drive_mode = ((geom.flags & BIOSDISK_FLAG_LBA_EXTENSION)
+			  ? MB_DI_LBA_MODE : MB_DI_CHS_MODE);
+      info->drive_cylinders = geom.cylinders;
+      info->drive_heads = geom.heads;
+      info->drive_sectors = geom.sectors;
+
+      addr += sizeof (struct drive_info);
+      for (port = io_map; *port; port++, addr += sizeof (unsigned short))
+	*((unsigned short *) addr) = *port;
+
+      info->size = addr - (unsigned long) info;
+      mbi.drives_length += info->size;
+    }
+
+  /* Get the ROM configuration table by INT 15, AH=C0h.  */
+  mbi.config_table = get_rom_config_table ();
+
+  /* Set the boot loader name.  */
+  mbi.boot_loader_name = (unsigned long) "GNU GRUB " VERSION;
+  
   /*
    *  Initialize other Multiboot Info flags.
    */
 
-  mbi.flags = MB_INFO_MEMORY | MB_INFO_CMDLINE | MB_INFO_BOOTDEV;
+  mbi.flags = (MB_INFO_MEMORY | MB_INFO_CMDLINE | MB_INFO_BOOTDEV
+	       | MB_INFO_DRIVE_INFO | MB_INFO_CONFIG_TABLE
+	       | MB_INFO_BOOT_LOADER_NAME);
 
 #endif /* STAGE1_5 */
 

stage2/mb_info.h

@@ -23,7 +23,7 @@
  */
 
 struct mod_list
-  {
+{
   /* the memory used goes from bytes 'mod_start' to 'mod_end-1' inclusive */
   unsigned long mod_start;
   unsigned long mod_end;
@@ -33,7 +33,7 @@ struct mod_list
   
   /* padding to take it to 16 bytes (must be zero) */
   unsigned long pad;
-  };
+};
 
 
 /*
@@ -44,19 +44,45 @@ struct mod_list
  */
 
 struct AddrRangeDesc
-  {
+{
   unsigned long size;
   unsigned long long BaseAddr;
   unsigned long long Length;
   unsigned long Type;
   
   /* unspecified optional padding... */
-  };
+};
 
 /* usable memory "Type", all others are reserved.  */
 #define MB_ARD_MEMORY       1
 
 
+/* Drive Info structure.  */
+struct drive_info
+{
+  /* The size of this structure.  */
+  unsigned long size;
+
+  /* The BIOS drive number.  */
+  unsigned char drive_number;
+
+  /* The access mode (see below).  */
+  unsigned char drive_mode;
+
+  /* The BIOS geometry.  */
+  unsigned short drive_cylinders;
+  unsigned char drive_heads;
+  unsigned char drive_sectors;
+
+  /* The array of I/O ports used for the drive.  */
+  unsigned short drive_ports[0];
+};
+
+/* Drive Mode.  */
+#define MB_DI_CHS_MODE	0
+#define MB_DI_LBA_MODE	1
+
+
 /*
  *  MultiBoot Info description
  *
@@ -65,7 +91,7 @@ struct AddrRangeDesc
  */
 
 struct multiboot_info
-  {
+{
   /* MultiBoot info version number */
   unsigned long flags;
   
@@ -110,7 +136,17 @@ struct multiboot_info
   /* Memory Mapping buffer */
   unsigned long mmap_length;
   unsigned long mmap_addr;
-  };
+  
+  /* Drive Info buffer */
+  unsigned long drives_length;
+  unsigned long drives_addr;
+  
+  /* ROM configuration table */
+  unsigned long config_table;
+  
+  /* Boot Loader Name */
+  unsigned long boot_loader_name;
+};
 
 /*
  *  Flags to be set in the 'flags' parameter above
@@ -135,6 +171,15 @@ struct multiboot_info
 /* is there a full memory map? */
 #define MB_INFO_MEM_MAP         0x40
 
+/* Is there drive info?  */
+#define MB_INFO_DRIVE_INFO	0x80
+
+/* Is there a config table?  */
+#define MB_INFO_CONFIG_TABLE	0x100
+
+/* Is there a boot loader name?  */
+#define MB_INFO_BOOT_LOADER_NAME	0x200
+
 /*
  *  The following value must be present in the EAX register.
  */

stage2/shared.h

@@ -643,6 +643,10 @@ int get_eisamemsize (void);
    map). */
 int get_mmap_entry (struct mmar_desc *desc, int cont);
 
+/* Get the linear address of a ROM configuration table. Return zero,
+   if fails.  */
+unsigned long get_rom_config_table (void);
+
 /* Return the data area immediately following our code. */
 int get_code_end (void);
 

stage2/stage2.c

@@ -797,7 +797,7 @@ cmain (void)
       config_len = 0;
       menu_len = 0;
       num_entries = 0;
-      config_entries = (char *) (mbi.mmap_addr + mbi.mmap_length);
+      config_entries = (char *) mbi.drives_addr + mbi.drives_length;
       menu_entries = (char *) MENU_BUF;
       init_config ();