From edba90fb16ec7224da591ab8f83efe3673853a3f Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Wed, 20 May 2015 16:03:33 +0200 Subject: first commit Based on x86/bios from lkvm Signed-off-by: Paolo Bonzini --- Makefile | 27 ++++++++ code16gcc.h | 14 +++++ e820.c | 70 +++++++++++++++++++++ entry.S | 95 ++++++++++++++++++++++++++++ include/assembly.h | 29 +++++++++ include/bios.h | 64 +++++++++++++++++++ include/const.h | 27 ++++++++ include/e820.h | 66 ++++++++++++++++++++ include/processor-flags.h | 153 ++++++++++++++++++++++++++++++++++++++++++++++ include/segment.h | 19 ++++++ int10.c | 43 +++++++++++++ int15.c | 16 +++++ memcpy.o | Bin 0 -> 952 bytes rom.ld.S | 19 ++++++ 14 files changed, 642 insertions(+) create mode 100644 Makefile create mode 100644 code16gcc.h create mode 100644 e820.c create mode 100644 entry.S create mode 100644 include/assembly.h create mode 100644 include/bios.h create mode 100644 include/const.h create mode 100644 include/e820.h create mode 100644 include/processor-flags.h create mode 100644 include/segment.h create mode 100644 int10.c create mode 100644 int15.c create mode 100644 memcpy.o create mode 100644 rom.ld.S diff --git a/Makefile b/Makefile new file mode 100644 index 0000000..0fb6c95 --- /dev/null +++ b/Makefile @@ -0,0 +1,27 @@ +obj16-y = e820.o int10.o int15.o +obj-y = $(obj16-y) entry.o +all-y = bios.bin + +BIOS_CFLAGS += -m32 +BIOS_CFLAGS += -march=i386 +BIOS_CFLAGS += -mregparm=3 +BIOS_CFLAGS += -fno-stack-protector +BIOS_CFLAGS += -Iinclude +$(obj16-y): BIOS_CFLAGS += -include code16gcc.h + +all: $(all-y) + +.PRECIOUS: %.o +%.o: %.c + $(CC) $(CFLAGS) $(BIOS_CFLAGS) -c -s $< -o $@ +%.o: %.S + $(CC) $(CFLAGS) $(BIOS_CFLAGS) -c -s $< -o $@ + +bios.bin.elf: $(obj-y) rom.ld.S + $(LD) -T rom.ld.S -o bios.bin.elf $(obj-y) + +bios.bin: bios.bin.elf + objcopy -O binary bios.bin.elf bios.bin + +clean: + rm $(obj-y) $(all-y) bios.bin.elf diff --git a/code16gcc.h b/code16gcc.h new file mode 100644 index 0000000..a4feb62 --- /dev/null +++ b/code16gcc.h @@ -0,0 +1,14 @@ +/* + * code16gcc.h + * + * This file is -include'd when compiling 16-bit C code. + * Note: this asm() needs to be emitted before gcc emits any code. + * Depending on gcc version, this requires -fno-unit-at-a-time or + * -fno-toplevel-reorder. + * + * Hopefully gcc will eventually have a real -m16 option so we can + * drop this hack long term. + */ + + +asm(".code16gcc"); diff --git a/e820.c b/e820.c new file mode 100644 index 0000000..4eab157 --- /dev/null +++ b/e820.c @@ -0,0 +1,70 @@ +#include "bios.h" +#include "segment.h" + +#include "processor-flags.h" +#include "e820.h" + +static inline void set_fs(uint16_t seg) +{ + asm volatile("movw %0,%%fs" : : "rm" (seg)); +} + +static inline uint8_t rdfs8(unsigned long addr) +{ + uint8_t v; + + asm volatile("addr32 movb %%fs:%1,%0" : "=q" (v) : "m" (*(uint8_t *)addr)); + + return v; +} + +static inline uint32_t rdfs32(unsigned long addr) +{ + uint32_t v; + + asm volatile("addr32 movl %%fs:%1,%0" : "=q" (v) : "m" (*(uint32_t *)addr)); + + return v; +} + +bioscall void e820_query_map(struct biosregs *regs) +{ + struct e820map *e820; + uint32_t map_size; + uint16_t fs_seg; + uint32_t ndx; + + e820 = (struct e820map *)E820_MAP_START; + fs_seg = flat_to_seg16(E820_MAP_START); + set_fs(fs_seg); + + ndx = regs->ebx; + + map_size = rdfs32(flat_to_off16((uint32_t)&e820->nr_map, fs_seg)); + + if (ndx < map_size) { + uint32_t start; + unsigned int i; + uint8_t *p; + + fs_seg = flat_to_seg16(E820_MAP_START); + set_fs(fs_seg); + + start = (uint32_t)&e820->map[ndx]; + + p = (void *) regs->edi; + + for (i = 0; i < sizeof(struct e820entry); i++) + *p++ = rdfs8(flat_to_off16(start + i, fs_seg)); + } + + regs->eax = SMAP; + regs->ecx = sizeof(struct e820entry); + regs->ebx = ++ndx; + + /* Clear CF to indicate success. */ + regs->eflags &= ~X86_EFLAGS_CF; + + if (ndx >= map_size) + regs->ebx = 0; /* end of map */ +} diff --git a/entry.S b/entry.S new file mode 100644 index 0000000..a192c7d --- /dev/null +++ b/entry.S @@ -0,0 +1,95 @@ +/* + * Our pretty trivial BIOS emulation + */ + +#include "assembly.h" +#include "processor-flags.h" + + .org 0 + .code16gcc + +/* + * handy BIOS macros + */ + +/* If you change these macros, remember to update 'struct biosregs' */ +.macro SAVE_BIOSREGS + pushl %fs + pushl %es + pushl %ds + pushl %edi + pushl %esi + pushl %ebp + pushl %esp + pushl %edx + pushl %ecx + pushl %ebx + pushl %eax +.endm + +.macro RESTORE_BIOSREGS + popl %eax + popl %ebx + popl %ecx + popl %edx + popl %esp + popl %ebp + popl %esi + popl %edi + popl %ds + popl %es + popl %fs +.endm + +/* + * fake interrupt handler, nothing can be faster ever + */ +ENTRY(bios_intfake) + /* + * Set CF to indicate failure. We don't want callers to think that the + * interrupt handler succeeded and then treat the return values in + * registers as valid data. + */ + orl $X86_EFLAGS_CF, 0x4(%esp) + + IRET +ENTRY_END(bios_intfake) + +/* + * int 10 - video - service + */ +ENTRY(bios_int10) + SAVE_BIOSREGS + + movl %esp, %eax + /* this is way easier than doing it in assembly */ + /* just push all the regs and jump to a C handler */ + call int10_handler + + RESTORE_BIOSREGS + + /* Clear CF to indicate success. */ + andl $~X86_EFLAGS_CF, 0x4(%esp) + + IRET +ENTRY_END(bios_int10) + +ENTRY(bios_int15) + SAVE_BIOSREGS + + movl %esp, %eax + call int15_handler + + RESTORE_BIOSREGS + + IRET +ENTRY_END(bios_int15) + +ENTRY(real_entry) + cli + hlt +ENTRY_END(real_entry) + + ORG(fff0) + jmp real_entry + diff --git a/include/assembly.h b/include/assembly.h new file mode 100644 index 0000000..3601024 --- /dev/null +++ b/include/assembly.h @@ -0,0 +1,29 @@ +#ifndef ASSEMBLY_H_ +#define ASSEMBLY_H_ + +#define __ASSEMBLY__ + +#define ORG(x) \ + .section .fixedaddr._##x + +#define __ALIGN .p2align 4, 0x90 +#define ENTRY(name) \ + __ALIGN; \ + .globl name; \ + name: + +#define GLOBAL(name) \ + .globl name; \ + name: + +#define ENTRY_END(name) GLOBAL(name##_end) +#define END(name) GLOBAL(name##_end) + +/* + * gas produces size override prefix with which + * we are unhappy, lets make it hardcoded for + * 16 bit mode + */ +#define IRET .byte 0xcf + +#endif /* ASSEMBLY_H_ */ diff --git a/include/bios.h b/include/bios.h new file mode 100644 index 0000000..153c887 --- /dev/null +++ b/include/bios.h @@ -0,0 +1,64 @@ +#ifndef BIOS_H_ +#define BIOS_H_ + +#include + +/* + * X86-32 Memory Map (typical) + * start end + * Real Mode Interrupt Vector Table 0x00000000 0x000003FF + * BDA area 0x00000400 0x000004FF + * Conventional Low Memory 0x00000500 0x0009FBFF + * EBDA area 0x0009FC00 0x0009FFFF + * VIDEO RAM 0x000A0000 0x000BFFFF + * VIDEO ROM (BIOS) 0x000C0000 0x000C7FFF + * ROMs & unus. space (mapped hw & misc)0x000C8000 0x000EFFFF 160 KiB (typically) + * Motherboard BIOS 0x000F0000 0x000FFFFF + * Extended Memory 0x00100000 0xFEBFFFFF + * Reserved (configs, ACPI, PnP, etc) 0xFEC00000 0xFFFFFFFF + */ + +#define REAL_MODE_IVT_BEGIN 0x00000000 +#define REAL_MODE_IVT_END 0x000003ff + +#define BDA_START 0x00000400 +#define BDA_END 0x000004ff + +#define EBDA_START 0x0009fc00 +#define EBDA_END 0x0009ffff + +#define E820_MAP_START EBDA_START + +/* + * When interfacing with assembler code we need to be sure how + * arguments are passed in real mode. + */ +#define bioscall __attribute__((regparm(3))) + +#ifndef __ASSEMBLER__ + +#include + +struct biosregs { + uint32_t eax; + uint32_t ebx; + uint32_t ecx; + uint32_t edx; + uint32_t esp; + uint32_t ebp; + uint32_t esi; + uint32_t edi; + uint32_t ds; + uint32_t es; + uint32_t fs; + uint32_t eip; + uint32_t eflags; +}; + +extern bioscall void int10_handler(struct biosregs *regs); +extern bioscall void int15_handler(struct biosregs *regs); +extern bioscall void e820_query_map(struct biosregs *regs); + +#endif + +#endif /* BIOS_H_ */ diff --git a/include/const.h b/include/const.h new file mode 100644 index 0000000..3d5213f --- /dev/null +++ b/include/const.h @@ -0,0 +1,27 @@ +/* const.h: Macros for dealing with constants. */ + +#ifndef _LINUX_CONST_H +#define _LINUX_CONST_H + +/* Some constant macros are used in both assembler and + * C code. Therefore we cannot annotate them always with + * 'UL' and other type specifiers unilaterally. We + * use the following macros to deal with this. + * + * Similarly, _AT() will cast an expression with a type in C, but + * leave it unchanged in asm. + */ + +#ifdef __ASSEMBLY__ +#define _AC(X,Y) X +#define _AT(T,X) X +#else +#define __AC(X,Y) (X##Y) +#define _AC(X,Y) __AC(X,Y) +#define _AT(T,X) ((T)(X)) +#endif + +#define BITUL(x) (_AC(1,UL) << (x)) +#define BITULL(x) (_AC(1,ULL) << (x)) + +#endif /* !(_LINUX_CONST_H) */ diff --git a/include/e820.h b/include/e820.h new file mode 100644 index 0000000..1dfd18f --- /dev/null +++ b/include/e820.h @@ -0,0 +1,66 @@ +#ifndef _UAPI_ASM_X86_E820_H +#define _UAPI_ASM_X86_E820_H + +#define SMAP 0x534d4150 /* ASCII "SMAP" */ +#define E820MAP 0x2d0 /* our map */ +#define E820MAX 128 /* number of entries in E820MAP */ + +/* + * Legacy E820 BIOS limits us to 128 (E820MAX) nodes due to the + * constrained space in the zeropage. If we have more nodes than + * that, and if we've booted off EFI firmware, then the EFI tables + * passed us from the EFI firmware can list more nodes. Size our + * internal memory map tables to have room for these additional + * nodes, based on up to three entries per node for which the + * kernel was built: MAX_NUMNODES == (1 << CONFIG_NODES_SHIFT), + * plus E820MAX, allowing space for the possible duplicate E820 + * entries that might need room in the same arrays, prior to the + * call to sanitize_e820_map() to remove duplicates. The allowance + * of three memory map entries per node is "enough" entries for + * the initial hardware platform motivating this mechanism to make + * use of additional EFI map entries. Future platforms may want + * to allow more than three entries per node or otherwise refine + * this size. + */ + +#define E820_X_MAX E820MAX + +#define E820NR 0x1e8 /* # entries in E820MAP */ + +#define E820_RAM 1 +#define E820_RESERVED 2 +#define E820_ACPI 3 +#define E820_NVS 4 +#define E820_UNUSABLE 5 + + +/* + * reserved RAM used by kernel itself + * if CONFIG_INTEL_TXT is enabled, memory of this type will be + * included in the S3 integrity calculation and so should not include + * any memory that BIOS might alter over the S3 transition + */ +#define E820_RESERVED_KERN 128 + +struct e820entry { + uint64_t addr; /* start of memory segment */ + uint64_t size; /* size of memory segment */ + uint32_t type; /* type of memory segment */ +} __attribute__((packed)); + +struct e820map { + uint32_t nr_map; + struct e820entry map[E820_X_MAX]; +}; + +#define ISA_START_ADDRESS 0xa0000 +#define ISA_END_ADDRESS 0x100000 + +#define BIOS_BEGIN 0x000a0000 +#define BIOS_END 0x00100000 + +#define BIOS_ROM_BASE 0xffe00000 +#define BIOS_ROM_END 0xffffffff + + +#endif /* _UAPI_ASM_X86_E820_H */ diff --git a/include/processor-flags.h b/include/processor-flags.h new file mode 100644 index 0000000..2725d27 --- /dev/null +++ b/include/processor-flags.h @@ -0,0 +1,153 @@ +#ifndef _UAPI_ASM_X86_PROCESSOR_FLAGS_H +#define _UAPI_ASM_X86_PROCESSOR_FLAGS_H +/* Various flags defined: can be included from assembler. */ + +#include "const.h" + +/* + * EFLAGS bits + */ +#define X86_EFLAGS_CF_BIT 0 /* Carry Flag */ +#define X86_EFLAGS_CF BITUL(X86_EFLAGS_CF_BIT) +#define X86_EFLAGS_FIXED_BIT 1 /* Bit 1 - always on */ +#define X86_EFLAGS_FIXED BITUL(X86_EFLAGS_FIXED_BIT) +#define X86_EFLAGS_PF_BIT 2 /* Parity Flag */ +#define X86_EFLAGS_PF BITUL(X86_EFLAGS_PF_BIT) +#define X86_EFLAGS_AF_BIT 4 /* Auxiliary carry Flag */ +#define X86_EFLAGS_AF BITUL(X86_EFLAGS_AF_BIT) +#define X86_EFLAGS_ZF_BIT 6 /* Zero Flag */ +#define X86_EFLAGS_ZF BITUL(X86_EFLAGS_ZF_BIT) +#define X86_EFLAGS_SF_BIT 7 /* Sign Flag */ +#define X86_EFLAGS_SF BITUL(X86_EFLAGS_SF_BIT) +#define X86_EFLAGS_TF_BIT 8 /* Trap Flag */ +#define X86_EFLAGS_TF BITUL(X86_EFLAGS_TF_BIT) +#define X86_EFLAGS_IF_BIT 9 /* Interrupt Flag */ +#define X86_EFLAGS_IF BITUL(X86_EFLAGS_IF_BIT) +#define X86_EFLAGS_DF_BIT 10 /* Direction Flag */ +#define X86_EFLAGS_DF BITUL(X86_EFLAGS_DF_BIT) +#define X86_EFLAGS_OF_BIT 11 /* Overflow Flag */ +#define X86_EFLAGS_OF BITUL(X86_EFLAGS_OF_BIT) +#define X86_EFLAGS_IOPL_BIT 12 /* I/O Privilege Level (2 bits) */ +#define X86_EFLAGS_IOPL (_AC(3,UL) << X86_EFLAGS_IOPL_BIT) +#define X86_EFLAGS_NT_BIT 14 /* Nested Task */ +#define X86_EFLAGS_NT BITUL(X86_EFLAGS_NT_BIT) +#define X86_EFLAGS_RF_BIT 16 /* Resume Flag */ +#define X86_EFLAGS_RF BITUL(X86_EFLAGS_RF_BIT) +#define X86_EFLAGS_VM_BIT 17 /* Virtual Mode */ +#define X86_EFLAGS_VM BITUL(X86_EFLAGS_VM_BIT) +#define X86_EFLAGS_AC_BIT 18 /* Alignment Check/Access Control */ +#define X86_EFLAGS_AC BITUL(X86_EFLAGS_AC_BIT) +#define X86_EFLAGS_AC_BIT 18 /* Alignment Check/Access Control */ +#define X86_EFLAGS_AC BITUL(X86_EFLAGS_AC_BIT) +#define X86_EFLAGS_VIF_BIT 19 /* Virtual Interrupt Flag */ +#define X86_EFLAGS_VIF BITUL(X86_EFLAGS_VIF_BIT) +#define X86_EFLAGS_VIP_BIT 20 /* Virtual Interrupt Pending */ +#define X86_EFLAGS_VIP BITUL(X86_EFLAGS_VIP_BIT) +#define X86_EFLAGS_ID_BIT 21 /* CPUID detection */ +#define X86_EFLAGS_ID BITUL(X86_EFLAGS_ID_BIT) + +/* + * Basic CPU control in CR0 + */ +#define X86_CR0_PE_BIT 0 /* Protection Enable */ +#define X86_CR0_PE BITUL(X86_CR0_PE_BIT) +#define X86_CR0_MP_BIT 1 /* Monitor Coprocessor */ +#define X86_CR0_MP BITUL(X86_CR0_MP_BIT) +#define X86_CR0_EM_BIT 2 /* Emulation */ +#define X86_CR0_EM BITUL(X86_CR0_EM_BIT) +#define X86_CR0_TS_BIT 3 /* Task Switched */ +#define X86_CR0_TS BITUL(X86_CR0_TS_BIT) +#define X86_CR0_ET_BIT 4 /* Extension Type */ +#define X86_CR0_ET BITUL(X86_CR0_ET_BIT) +#define X86_CR0_NE_BIT 5 /* Numeric Error */ +#define X86_CR0_NE BITUL(X86_CR0_NE_BIT) +#define X86_CR0_WP_BIT 16 /* Write Protect */ +#define X86_CR0_WP BITUL(X86_CR0_WP_BIT) +#define X86_CR0_AM_BIT 18 /* Alignment Mask */ +#define X86_CR0_AM BITUL(X86_CR0_AM_BIT) +#define X86_CR0_NW_BIT 29 /* Not Write-through */ +#define X86_CR0_NW BITUL(X86_CR0_NW_BIT) +#define X86_CR0_CD_BIT 30 /* Cache Disable */ +#define X86_CR0_CD BITUL(X86_CR0_CD_BIT) +#define X86_CR0_PG_BIT 31 /* Paging */ +#define X86_CR0_PG BITUL(X86_CR0_PG_BIT) + +/* + * Paging options in CR3 + */ +#define X86_CR3_PWT_BIT 3 /* Page Write Through */ +#define X86_CR3_PWT BITUL(X86_CR3_PWT_BIT) +#define X86_CR3_PCD_BIT 4 /* Page Cache Disable */ +#define X86_CR3_PCD BITUL(X86_CR3_PCD_BIT) +#define X86_CR3_PCID_MASK _AC(0x00000fff,UL) /* PCID Mask */ + +/* + * Intel CPU features in CR4 + */ +#define X86_CR4_VME_BIT 0 /* enable vm86 extensions */ +#define X86_CR4_VME BITUL(X86_CR4_VME_BIT) +#define X86_CR4_PVI_BIT 1 /* virtual interrupts flag enable */ +#define X86_CR4_PVI BITUL(X86_CR4_PVI_BIT) +#define X86_CR4_TSD_BIT 2 /* disable time stamp at ipl 3 */ +#define X86_CR4_TSD BITUL(X86_CR4_TSD_BIT) +#define X86_CR4_DE_BIT 3 /* enable debugging extensions */ +#define X86_CR4_DE BITUL(X86_CR4_DE_BIT) +#define X86_CR4_PSE_BIT 4 /* enable page size extensions */ +#define X86_CR4_PSE BITUL(X86_CR4_PSE_BIT) +#define X86_CR4_PAE_BIT 5 /* enable physical address extensions */ +#define X86_CR4_PAE BITUL(X86_CR4_PAE_BIT) +#define X86_CR4_MCE_BIT 6 /* Machine check enable */ +#define X86_CR4_MCE BITUL(X86_CR4_MCE_BIT) +#define X86_CR4_PGE_BIT 7 /* enable global pages */ +#define X86_CR4_PGE BITUL(X86_CR4_PGE_BIT) +#define X86_CR4_PCE_BIT 8 /* enable performance counters at ipl 3 */ +#define X86_CR4_PCE BITUL(X86_CR4_PCE_BIT) +#define X86_CR4_OSFXSR_BIT 9 /* enable fast FPU save and restore */ +#define X86_CR4_OSFXSR BITUL(X86_CR4_OSFXSR_BIT) +#define X86_CR4_OSXMMEXCPT_BIT 10 /* enable unmasked SSE exceptions */ +#define X86_CR4_OSXMMEXCPT BITUL(X86_CR4_OSXMMEXCPT_BIT) +#define X86_CR4_VMXE_BIT 13 /* enable VMX virtualization */ +#define X86_CR4_VMXE BITUL(X86_CR4_VMXE_BIT) +#define X86_CR4_SMXE_BIT 14 /* enable safer mode (TXT) */ +#define X86_CR4_SMXE BITUL(X86_CR4_SMXE_BIT) +#define X86_CR4_FSGSBASE_BIT 16 /* enable RDWRFSGS support */ +#define X86_CR4_FSGSBASE BITUL(X86_CR4_FSGSBASE_BIT) +#define X86_CR4_PCIDE_BIT 17 /* enable PCID support */ +#define X86_CR4_PCIDE BITUL(X86_CR4_PCIDE_BIT) +#define X86_CR4_OSXSAVE_BIT 18 /* enable xsave and xrestore */ +#define X86_CR4_OSXSAVE BITUL(X86_CR4_OSXSAVE_BIT) +#define X86_CR4_SMEP_BIT 20 /* enable SMEP support */ +#define X86_CR4_SMEP BITUL(X86_CR4_SMEP_BIT) +#define X86_CR4_SMAP_BIT 21 /* enable SMAP support */ +#define X86_CR4_SMAP BITUL(X86_CR4_SMAP_BIT) + +/* + * x86-64 Task Priority Register, CR8 + */ +#define X86_CR8_TPR _AC(0x0000000f,UL) /* task priority register */ + +/* + * AMD and Transmeta use MSRs for configuration; see + */ + +/* + * NSC/Cyrix CPU configuration register indexes + */ +#define CX86_PCR0 0x20 +#define CX86_GCR 0xb8 +#define CX86_CCR0 0xc0 +#define CX86_CCR1 0xc1 +#define CX86_CCR2 0xc2 +#define CX86_CCR3 0xc3 +#define CX86_CCR4 0xe8 +#define CX86_CCR5 0xe9 +#define CX86_CCR6 0xea +#define CX86_CCR7 0xeb +#define CX86_PCR1 0xf0 +#define CX86_DIR0 0xfe +#define CX86_DIR1 0xff +#define CX86_ARR_BASE 0xc4 +#define CX86_RCR_BASE 0xdc + + +#endif /* _UAPI_ASM_X86_PROCESSOR_FLAGS_H */ diff --git a/include/segment.h b/include/segment.h new file mode 100644 index 0000000..694eb4b --- /dev/null +++ b/include/segment.h @@ -0,0 +1,19 @@ +#ifndef KVM_SEGMENT_H +#define KVM_SEGMENT_H + +static inline uint32_t segment_to_flat(uint16_t selector, uint16_t offset) +{ + return ((uint32_t)selector << 4) + (uint32_t) offset; +} + +static inline uint16_t flat_to_seg16(uint32_t address) +{ + return address >> 4; +} + +static inline uint16_t flat_to_off16(uint32_t address, uint32_t segment) +{ + return address - (segment << 4); +} + +#endif /* KVM_SEGMENT_H */ diff --git a/int10.c b/int10.c new file mode 100644 index 0000000..9d9604c --- /dev/null +++ b/int10.c @@ -0,0 +1,43 @@ +#include "bios.h" +#include "segment.h" + +static inline void outb(unsigned short port, unsigned char val) +{ + asm volatile("outb %0, %1" : : "a"(val), "Nd"(port)); +} + +/* + * It's probably much more useful to make this print to the serial + * line rather than print to a non-displayed VGA memory + */ +static inline void int10_putchar(struct biosregs *args) +{ + uint8_t al = args->eax & 0xFF; + + outb(0x3f8, al); +} + +#define VBE_STATUS_OK 0x004F +#define VBE_STATUS_FAIL 0x014F + +static void int10_vesa(struct biosregs *args) +{ + args->eax = VBE_STATUS_FAIL; +} + +bioscall void int10_handler(struct biosregs *args) +{ + uint8_t ah; + + ah = (args->eax & 0xff00) >> 8; + + switch (ah) { + case 0x0e: + int10_putchar(args); + break; + case 0x4f: + int10_vesa(args); + break; + } + +} diff --git a/int15.c b/int15.c new file mode 100644 index 0000000..d8ff820 --- /dev/null +++ b/int15.c @@ -0,0 +1,16 @@ +#include "bios.h" + +#include "processor-flags.h" + +bioscall void int15_handler(struct biosregs *regs) +{ + switch (regs->eax) { + case 0xe820: + e820_query_map(regs); + break; + default: + /* Set CF to indicate failure. */ + regs->eflags |= X86_EFLAGS_CF; + break; + } +} diff --git a/memcpy.o b/memcpy.o new file mode 100644 index 0000000..d24e386 Binary files /dev/null and b/memcpy.o differ diff --git a/rom.ld.S b/rom.ld.S new file mode 100644 index 0000000..04f2ff9 --- /dev/null +++ b/rom.ld.S @@ -0,0 +1,19 @@ +OUTPUT_FORMAT("elf32-i386", "elf32-i386", "elf32-i386") +OUTPUT_ARCH(i386) + +SECTIONS { + .text 0 : { + *(.text) + . = 0xfff0 ; + *(.fixedaddr._fff0) + . = 0x10000 ; + } + + /DISCARD/ : { + *(.debug*) + *(.data) + *(.bss) + *(.eh_frame*) + } +} + -- cgit v1.1