diff -ruN /tmp/sos-code-article7.5/bootstrap/multiboot.h ../sos-code-article7.5/bootstrap/multiboot.h --- /tmp/sos-code-article7.5/bootstrap/multiboot.h 2005-04-27 20:17:12.000000000 +0200 +++ ../sos-code-article7.5/bootstrap/multiboot.h 2005-04-27 23:15:15.000000000 +0200 @@ -47,10 +47,12 @@ #include + /* The address of the stack of the bootstrap thread */ extern sos_vaddr_t bootstrap_stack_bottom; extern sos_size_t bootstrap_stack_size; + /* Types. */ /* The Multiboot header. */ diff -ruN /tmp/sos-code-article7.5/extra/bootsect.S ../sos-code-article7.5/extra/bootsect.S --- /tmp/sos-code-article7.5/extra/bootsect.S 2005-04-27 20:17:13.000000000 +0200 +++ ../sos-code-article7.5/extra/bootsect.S 2005-04-27 23:15:16.000000000 +0200 @@ -1,10 +1,11 @@ /* - * @(#) $Id: bootsect.S,v 1.8 2004/11/20 16:00:11 d2 Exp $ + * @(#) $Id: bootsect.S,v 1.9 2005/04/27 21:00:09 d2 Exp $ * Description : Bootsecteur en syntaxe AT&T * Auteurs : Thomas Petazzoni & Fabrice Gautier & Emmanuel Marty * Jerome Petazzoni & Bernard Cassagne & coffeeman * David Decotigny + * Christopher Goyet (RAM size determination through BIOS int 15H) * Bug reports to kos-misc@enix.org */ @@ -152,6 +153,12 @@ movb $0x3, %al int $0x10 + /* Recupere la taille de la RAM */ + mov $0xE801, %ax + int $0x15 + movw %ax, (memsize1) + movw %bx, (memsize2) + /* Affiche les messages d'attente */ movw $loadkern, %si call message @@ -313,6 +320,18 @@ movl %eax, %ss movl $(stack + BOOT_STACK_SIZE), %ebp movl %ebp, %esp + +/* passe les arguments a sos */ + xor %eax, %eax + xor %ebx, %ebx + movw (COPY_ADRESS+(memsize2)), %ax /*eax = num de block de 64KB apres 16MB*/ + movw (COPY_ADRESS+(memsize1)), %bx /*ebx = num de block de 1KB entre 1MB et 16MB*/ + movl $0x40, %ecx /*ecx=64 */ + mul %ecx + add %ebx, %eax + pushl %eax /* valeur de addr */ + pushl $0x42244224 /*valeur de magic = magic de grub -1 */ + pushl $0 /* normalement call fait un push eip, mais la on a un jmp*/ /* Saut vers le noyau. La GDT est en place (flat mode), les * selecteurs aussi, a20 est ouverte, et les interruptions sont @@ -373,7 +392,7 @@ /* quelques messages */ -loadkern: .string "-= S O S =- : The Simple Operating System \r\n" +loadkern: .string "S O S : The Simple Operating System \r\n" check: .string "Checking for a 386+ processor... " found386: .string " [OK]\r\n" need386: .string " [FAILED]\r\n" @@ -381,6 +400,10 @@ loading: .string "Loading... " haltmsg: .string "System Halted\r\n" + /* Variables pour stocker la taille de la RAM (int 0x15) */ +memsize1: .long 0 +memsize2: .long 0 + /*** Les code/données du boot secteur se terminent ICI. le marqueur de * fin (aa55) est ajouté automatiquement par le script ld * sos_bsect.lds ***/ diff -ruN /tmp/sos-code-article7.5/extra/Makefile ../sos-code-article7.5/extra/Makefile --- /tmp/sos-code-article7.5/extra/Makefile 2005-04-27 20:17:13.000000000 +0200 +++ ../sos-code-article7.5/extra/Makefile 2005-04-27 23:15:16.000000000 +0200 @@ -1,4 +1,6 @@ OBJCOPY=objcopy +LIBGCC := $(shell $(CC) -print-libgcc-file-name) # To benefit from FP/64bits artihm. +EXTRA := $(shell [ -f ../userland/userprogs.kimg ] && echo ../userland/userprogs.kimg) all: sos_qemu.img @@ -31,7 +33,8 @@ # above) because they share some symbol definitions sos_bsect.elf: bootsect.o compile_kernel $(LD) --warn-common -T ./sos_bsect.lds -o $@ \ - bootsect.o $(wildcard ../hwcore/*.o ../drivers/*.o ../sos/*.o) + bootsect.o $(wildcard ../hwcore/*.o ../drivers/*.o ../sos/*.o)\ + $(EXTRA) $(LIBGCC) compile_kernel: $(MAKE) -C .. diff -ruN /tmp/sos-code-article7.5/extra/README ../sos-code-article7.5/extra/README --- /tmp/sos-code-article7.5/extra/README 2005-04-27 20:17:13.000000000 +0200 +++ ../sos-code-article7.5/extra/README 2005-04-27 23:15:16.000000000 +0200 @@ -65,8 +65,15 @@ - for cross-architecture compilation: see above - cd to this extra/ directory - run 'make' - - the floppy image is: sos_bsect.img - NOTE : SOS will not boot correctly this way after article 2 ! + - the floppy image is: sos_bsect.img for use with bochs or on a real + floppy disk + to use the image under qemu: use sos_qemu.img + + NOTE : From article 2 onward, be warned that using this bootsect + might lead to system crashes. This would be because the + solution we use to retrieve the RAM size might not work + properly on some systems (BIOS buggy or more than 1G RAM). THE + best way to boot SOS is always to use Grub. -- diff -ruN /tmp/sos-code-article7.5/hwcore/swintr.h ../sos-code-article7.5/hwcore/swintr.h --- /tmp/sos-code-article7.5/hwcore/swintr.h 2005-04-27 20:17:16.000000000 +0200 +++ ../sos-code-article7.5/hwcore/swintr.h 2005-04-27 23:15:19.000000000 +0200 @@ -31,7 +31,6 @@ */ #define SOS_SWINTR_SOS_SYSCALL 0x42 - #if defined(KERNEL_SOS) && !defined(ASM_SOURCE) #include diff -ruN /tmp/sos-code-article7.5/INSTALL ../sos-code-article7.5/INSTALL --- /tmp/sos-code-article7.5/INSTALL 2005-04-27 20:17:12.000000000 +0200 +++ ../sos-code-article7.5/INSTALL 2005-04-27 23:15:15.000000000 +0200 @@ -64,9 +64,9 @@ copy the file 'fd.img' to a floppy, and boot from it 2nd method - => see extra/README to compile with the boot sector we provide (up to - article 2 only), copy the file 'extra/sos_bsect.img' to a floppy, - and boot from it + => see extra/README to compile with the boot sector we provide, + copy the file 'extra/sos_bsect.img' to a floppy, and boot from + it Inside a PC emulator (x86 and non-x86 hosts) @@ -78,6 +78,7 @@ installed: 'apt-get install libsdl1.2-dev' on debian testing/unstable). + 1/ Grub is installed on the host (x86 hosts only) - - - - - - - - - - - - - - - - - - - - - - - - - @@ -90,6 +91,7 @@ qemu: run 'qemu -fda fd.img' If grub hangs while loading the kernel, please go to method 2/ + 2/ Grub is not installed (all hosts) - - - - - - - - - - - - - - - - - - @@ -100,8 +102,9 @@ qemu: run 'qemu -fda fd.img' - 3/ Bonus: boot with the bootsector we provide (all hosts, up to art. 2 ONLY !) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + + 3/ Bonus: boot with the bootsector we provide (all hosts) + - - - - - - - - - - - - - - - - - - - - - - - - - - - - - See extra/README to generate a floppy image with the boot sector we provide, and: @@ -110,8 +113,10 @@ qemu: run 'qemu -fda extra/sos_qemu.img' - NOTE: After article 2, this way of booting is not supported: please - use the method 2/ above. + NOTE: This technique assumes that INT 15H is supported by the + machine's BIOS. This should be OK for the vast majority of targets + (bochs, qemu, recent machines), but we do not guarantee it. In case + of doubt, please use Grub. NOTE : recommended versions of the tools diff -ruN /tmp/sos-code-article7.5/README ../sos-code-article7.5/README --- /tmp/sos-code-article7.5/README 2005-04-27 20:17:12.000000000 +0200 +++ ../sos-code-article7.5/README 2005-04-27 23:15:15.000000000 +0200 @@ -33,8 +33,7 @@ i586-gnu) is available. Can be tested on real i486/pentium hardware, or on any host that can run an i486/pentium PC emulator (bochs or qemu) - - kernel loaded by grub, or by a sample bootsector (up to article 2 - ONLY) + - kernel loaded by grub or by a sample bootsector - clear separation of physical memory and virtual memory concepts, even inside the kernel: no identity-mapping of the physical memory inside the kernel (allows to move virtual mappings of kernel pages @@ -54,7 +53,7 @@ 'all' and 'clean' - bootstrap/ directory: code to load the kernel. Both the stuff needed for a multiboot-compliant loader (eg grub) AND a bootsector - are provided. The bootsector may only be used up to article 2. + are provided. - sos/ directory: the entry routine for the kernel (main.c), various systemwide header files, a set of common useful C routines ("nano-klibc"), and kernel subsystems (kernel memory management, diff -ruN /tmp/sos-code-article7.5/sos/main.c ../sos-code-article7.5/sos/main.c --- /tmp/sos-code-article7.5/sos/main.c 2005-04-27 20:17:17.000000000 +0200 +++ ../sos-code-article7.5/sos/main.c 2005-04-27 23:15:19.000000000 +0200 @@ -16,6 +16,8 @@ USA. */ +#include + /* Include definitions of the multiboot standard */ #include #include @@ -64,7 +66,6 @@ } } - /* Clock IRQ handler */ static void clk_it(int intid) { @@ -325,17 +326,14 @@ /* ====================================================================== * The C entry point of our operating system */ -void sos_main(unsigned long magic, unsigned long addr) +void sos_main(unsigned long magic, unsigned long arg) { unsigned i; sos_paddr_t sos_kernel_core_base_paddr, sos_kernel_core_top_paddr; struct sos_time tick_resolution; - /* Grub sends us a structure, called multiboot_info_t with a lot of - precious informations about the system, see the multiboot - documentation for more information. */ - multiboot_info_t *mbi; - mbi = (multiboot_info_t *) addr; + /* Size of RAM above 1MB. Might be undefined ! */ + unsigned long int upper_mem = 0; /* Setup bochs and console, and clear the console */ sos_bochs_setup(); @@ -345,15 +343,32 @@ /* Greetings from SOS */ if (magic == MULTIBOOT_BOOTLOADER_MAGIC) - /* Loaded with Grub */ - sos_x86_videomem_printf(1, 0, - SOS_X86_VIDEO_FG_YELLOW | SOS_X86_VIDEO_BG_BLUE, - "Welcome From GRUB to %s%c RAM is %dMB (upper mem = 0x%x kB)", - "SOS article 7.5", ',', - (unsigned)(mbi->mem_upper >> 10) + 1, - (unsigned)mbi->mem_upper); + { + /* Grub sends us a structure, called multiboot_info_t with a lot of + precious informations about the system, see the multiboot + documentation for more information. */ + multiboot_info_t *mbi = (multiboot_info_t *) arg; + upper_mem = mbi->mem_upper; + sos_x86_videomem_printf(1, 0, + SOS_X86_VIDEO_FG_YELLOW | SOS_X86_VIDEO_BG_BLUE, + "Welcome From GRUB to %s%c RAM is %dMB (upper mem = 0x%x kB)", + "SOS article 7.5", ',', + (unsigned)(upper_mem >> 10) + 1, + (unsigned)upper_mem); + } + else if (magic == 0x42244224) + { + /* Loaded with SOS bootsect */ + upper_mem = arg; + sos_x86_videomem_printf(1, 0, + SOS_X86_VIDEO_FG_YELLOW | SOS_X86_VIDEO_BG_BLUE, + "Welcome to %s%c RAM is %dMB (upper mem = 0x%x kB)", + "SOS article 7.5", ',', + (unsigned)(upper_mem >> 10) + 1, + (unsigned)upper_mem); + } else - /* Not loaded with grub */ + /* Not loaded with grub, not from an enhanced bootsect */ sos_x86_videomem_printf(1, 0, SOS_X86_VIDEO_FG_YELLOW | SOS_X86_VIDEO_BG_BLUE, "Welcome to SOS article 7.5"); @@ -376,14 +391,14 @@ tick_resolution = (struct sos_time) { .sec=0, .nanosec=10000000UL }; sos_time_subsysem_setup(& tick_resolution); - /* We need a multiboot-compliant boot loader to get the size of the RAM */ - if (magic != MULTIBOOT_BOOTLOADER_MAGIC) + /* We need to know the RAM size */ + if (upper_mem == 0) { sos_x86_videomem_putstring(20, 0, SOS_X86_VIDEO_FG_LTRED | SOS_X86_VIDEO_BG_BLUE | SOS_X86_VIDEO_FG_BLINKING, - "I'm not loaded with Grub !"); + "I don't know RAM size ! Load me with Grub..."); /* STOP ! */ for (;;) continue; @@ -404,7 +419,7 @@ /* Multiboot says: "The value returned for upper memory is maximally the address of the first upper memory hole minus 1 megabyte.". It also adds: "It is not guaranteed to be this value." aka "YMMV" ;) */ - sos_physmem_subsystem_setup((mbi->mem_upper<<10) + (1<<20), + sos_physmem_subsystem_setup((upper_mem<<10) + (1<<20), & sos_kernel_core_base_paddr, & sos_kernel_core_top_paddr); @@ -495,7 +510,6 @@ /* Start the 'init' process, which in turns launches the other programs */ start_init(); - /* * We can safely exit from this function now, for there is already * an idle Kernel thread ready to make the CPU busy working...