#define REAL_MODE_CS (4 << 3) // 0x20
#define REAL_MODE_DS (5 << 3) // 0x28
- .code16gcc
-
/****************************************************************
* Include of 16bit C code
****************************************************************/
- .globl bios16c_start, bios16c_end
-bios16c_start:
-.include "out/blob.proc.16.s"
- .text
-bios16c_end:
+ .code16gcc
+.include "out/blob.16.s"
/****************************************************************
- * POST handler
+ * Entry macros
****************************************************************/
+ // Call a C function - this does the minimal work necessary to
+ // call into C. It sets up %ds, backs up %es, and backs up
+ // those registers that are call clobbered by the C compiler.
+ .macro ENTRY cfunc
+ cld
+ pushl %eax // Save registers clobbered by C code
+ pushl %ecx
+ pushl %edx
+ pushw %es
+ pushw %ds
+ movw %ss, %ax // Move %ss to %ds
+ movw %ax, %ds
+ pushl %esp // Backup %esp, then clear high bits
+ movzwl %sp, %esp
+ calll \cfunc
+ popl %esp // Restore %esp (including high bits)
+ popw %ds // Restore registers saved above
+ popw %es
+ popl %edx
+ popl %ecx
+ popl %eax
+ .endm
+
+ // Call a C function with current register list as an
+ // argument. This backs up the registers and sets %eax
+ // to point to the backup. On return, the registers are
+ // restored from the structure.
+ .macro ENTRY_ARG cfunc
+ cld
+ pushl %eax // Save registers (matches struct bregs)
+ pushl %ecx
+ pushl %edx
+ pushl %ebx
+ pushl %esi
+ pushl %edi
+ pushw %es
+ pushw %ds
+ movw %ss, %ax // Move %ss to %ds
+ movw %ax, %ds
+ movl %esp, %ebx // Backup %esp, then zero high bits
+ movzwl %sp, %esp
+ movl %esp, %eax // First arg is pointer to struct bregs
+ calll \cfunc
+ movl %ebx, %esp // Restore %esp (including high bits)
+ popw %ds // Restore registers (from struct bregs)
+ popw %es
+ popl %edi
+ popl %esi
+ popl %ebx
+ popl %edx
+ popl %ecx
+ popl %eax
+ .endm
+
+ // As above, but don't mangle %esp
+ .macro ENTRY_ARG_ESP cfunc
+ cld
+ pushl %eax // Save registers (matches struct bregs)
+ pushl %ecx
+ pushl %edx
+ pushl %ebx
+ pushl %esi
+ pushl %edi
+ pushw %es
+ pushw %ds
+ movw %ss, %ax // Move %ss to %ds
+ movw %ax, %ds
+ movl %esp, %eax // First arg is pointer to struct bregs
+ calll \cfunc
+ popw %ds // Restore registers (from struct bregs)
+ popw %es
+ popl %edi
+ popl %esi
+ popl %ebx
+ popl %edx
+ popl %ecx
+ popl %eax
+ .endm
+
// Macro to reset the 16bit stack
// Clobbers %ax
.macro RESET_STACK
xorw %ax, %ax
movw %ax, %ss
- movl $ CONFIG_STACK_OFFSET , %esp
+ movl $ BUILD_STACK_ADDR , %esp
+ .endm
+
+ // Specify a location in the fixed part of bios area.
+ .macro ORG addr
+ .section .text.fixed.addr
+ .org \addr - BUILD_START_FIXED
.endm
- .org 0xe05b
- .globl post16
+
+/****************************************************************
+ * POST handler
+ ****************************************************************/
+
+ ORG 0xe05b
post16:
// init the stack pointer
RESET_STACK
- // Set entry point of rombios32 code - the actual address
- // is altered later in the build process.
- .globl set_entry32
-set_entry32:
- pushl $0xf0000000
+ pushl $_code32__start
+
+ cld
// Fall through to transition32 function below
movl %eax, %cr0
// start protected mode code
- // ljmpl $PROTECTED_MODE_CS, $(1f | 0xf0000)
- .word 0xea66, 1f, 0x000f, PROTECTED_MODE_CS
+ .set __trans32, (BUILD_BIOS_ADDR + 1f)
+ ljmpl $PROTECTED_MODE_CS, $__trans32
.code32
1:
movw %ax, %fs
movw %ax, %gs
- cld
-
retl
// Call a 16bit function from 32bit mode.
// %eax = address of struct bregs
// Clobbers: all gp registers, flags, stack registers, cr0, idt/gdt
- .globl __call16_from32
+ .global __call16_from32
__call16_from32:
pushl %eax
// Jump to 16bit mode
- ljmp $0x20, $1f
+ ljmpw $REAL_MODE_CS, $1f
.code16gcc
1:
// restore data segment limits to 0xffff
- movw $0x28, %ax
+ movw $REAL_MODE_DS, %ax
movw %ax, %ds
movw %ax, %es
movw %ax, %ss
movl %eax, %cr0
// far jump to flush CPU queue after transition to real mode
- ljmpw $0xf000, $2f
+ ljmpw $SEG_BIOS, $2f
2:
// restore IDT to normal real-mode defaults
movw %ax, %ss // Assume stack is in segment 0
popl %eax
+
+ // Set __call16 return address to be transition32
pushl $transition32
// Fall through to __call16
// Call a 16bit function from 16bit mode with a specified cpu register state
// %eax = address of struct bregs
// Clobbers: all gp registers, es
- .globl __call16
+ .global __call16
__call16:
// Save eax
pushl %eax
// Setup for iretw call
- pushw $0xf000
+ pushw $SEG_BIOS
pushw $1f // return point
- pushw 0x28(%eax) // flags
- pushl 0x24(%eax) // CS:IP
+ pushw 0x20(%eax) // flags
+ pushl 0x1c(%eax) // CS:IP
// Load calling registers.
movl 0x04(%eax), %edi
movl 0x08(%eax), %esi
- movl 0x0c(%eax), %ebp
- movl 0x14(%eax), %ebx
- movl 0x18(%eax), %edx
- movl 0x1c(%eax), %ecx
+ movl 0x0c(%eax), %ebx
+ movl 0x10(%eax), %edx
+ movl 0x14(%eax), %ecx
movw 0x02(%eax), %es // XXX - should load %ds too
- movl 0x20(%eax), %eax
+ movl 0x18(%eax), %eax
// Invoke call
iretw // XXX - just do a lcalll
pushfw
pushl %eax
movl 0x06(%esp), %eax
- movl %ecx, 0x1c(%eax) // Save %ecx
+ movl %ecx, %ss:0x14(%eax) // Save %ecx
+ movw %ss, %cx
+ movw %cx, %ds // Restore %ds == %ss
popl %ecx
- movl %ecx, 0x20(%eax) // Save %eax
+ movl %ecx, 0x18(%eax) // Save %eax
popw %cx
- movw %cx, 0x28(%eax) // Save flags
+ movw %cx, 0x20(%eax) // Save flags
// Store remaining registers
movw %es, 0x02(%eax)
movl %edi, 0x04(%eax)
movl %esi, 0x08(%eax)
- movl %ebp, 0x0c(%eax)
- movl %ebx, 0x14(%eax)
- movl %edx, 0x18(%eax)
+ movl %ebx, 0x0c(%eax)
+ movl %edx, 0x10(%eax)
// Remove %eax
popl %eax
+ cld
+
retl
+// APM trampolines
+ .global apm16protected_entry
+apm16protected_entry:
+ pushfw // save flags
+ pushl %eax // dummy
+ ENTRY_ARG handle_1553
+ addw $4, %sp // pop dummy
+ popfw // restore flags
+ lretw
+
+ .code32
+ .global apm32protected_entry
+apm32protected_entry:
+ pushfw
+ pushw %cs // Setup for long jump to 16bit mode
+ pushw $1f
+ addw $8, 2(%esp)
+ ljmpw *(%esp)
+ .code16gcc
+1:
+ ENTRY_ARG_ESP handle_1553
+
+ movw $2f,(%esp) // Setup for long jump back to 32bit mode
+ subw $8, 2(%esp)
+ ljmpw *(%esp)
+ .code32
+2:
+ addl $4, %esp // pop call address
+ popfw
+ lretl
+ .code16gcc
+
+
/****************************************************************
* GDT and IDT tables
****************************************************************/
// Set base to f0000 to correspond to beginning of BIOS,
// in case I actually define an IDT later
// Set limit to 0
+ .global pmode_IDT_info
pmode_IDT_info:
.word 0x0000 // limit 15:00
.long 0xf0000 // base 16:47
.word 0x03ff // limit 15:00
.long 0 // base 16:47
+ .global rombios32_gdt_48
rombios32_gdt_48:
.word 0x30
.word rombios32_gdt
* Interrupt entry points
****************************************************************/
- .macro ENTRY cfunc
- cli // In case something far-calls instead of using "int"
- pushal
- pushw %es
- pushw %ds
- movw %ss, %ax
- movw %ax, %ds
- movzwl %sp, %esp
- movl %esp, %eax
- calll \cfunc
- popw %ds
- popw %es
- popal
- .endm
-
+ // Define an entry point for an interrupt (no args passed).
.macro IRQ_ENTRY num
- .globl entry_\num
+ .global entry_\num
entry_\num :
+ cli // In case something far-calls instead of using "int"
ENTRY handle_\num
iretw
.endm
- .macro IRQ_TRAMPOLINE num
- .globl irq_trampoline_0x\num
- irq_trampoline_0x\num :
- int $0x\num
- lretw
+ // Define an entry point for an interrupt (can read/modify args).
+ .macro IRQ_ENTRY_ARG num
+ .global entry_\num
+ entry_\num :
+ cli // In case something far-calls instead of using "int"
+ ENTRY_ARG handle_\num
+ iretw
.endm
- .org 0xe2c3
+ ORG 0xe2c3
IRQ_ENTRY nmi
- IRQ_ENTRY 13
- IRQ_ENTRY 12
- IRQ_ENTRY 11
+ IRQ_ENTRY_ARG 13
+ IRQ_ENTRY_ARG 12
+ IRQ_ENTRY_ARG 11
IRQ_ENTRY 76
IRQ_ENTRY 1c
IRQ_ENTRY 70
+
+ ORG 0xe3fe
+ jmp entry_13
+
+ ORG 0xe401
+ // XXX - Fixed Disk Parameter Table
+
+ ORG 0xe6f2
+ jmp entry_19
+
+ ORG 0xe6f5
+.include "out/cbt.proc.16.s"
+ .text
+
+ ORG 0xe729
+ // XXX - Baud Rate Generator Table
+
+ ORG 0xe739
+ IRQ_ENTRY_ARG 14
+
IRQ_ENTRY 74
IRQ_ENTRY 75
- .globl entry_19
+ // int 18/19 are special - they reset the stack and do not return.
+ .global entry_19
entry_19:
RESET_STACK
- calll handle_19
+ ENTRY handle_19
- .globl entry_18
+ .global entry_18
entry_18:
RESET_STACK
- calll handle_18
+ ENTRY handle_18
+
+ // IRQ trampolines
+ .macro IRQ_TRAMPOLINE num
+ .global irq_trampoline_0x\num
+ irq_trampoline_0x\num :
+ int $0x\num
+ lretw
+ .endm
IRQ_TRAMPOLINE 02
IRQ_TRAMPOLINE 10
IRQ_TRAMPOLINE 13
IRQ_TRAMPOLINE 15
+ IRQ_TRAMPOLINE 16
IRQ_TRAMPOLINE 18
IRQ_TRAMPOLINE 19
IRQ_TRAMPOLINE 1c
IRQ_TRAMPOLINE 4a
- .org 0xe3fe
- jmp entry_13
-
- .org 0xe401
- // XXX - Fixed Disk Parameter Table
-
- .org 0xe6f2
- jmp entry_19
-
- .org 0xe6f5
-.include "out/cbt.proc.16.s"
- .text
+ ORG 0xe82e
+ IRQ_ENTRY_ARG 16
- .org 0xe729
- // XXX - Baud Rate Generator Table
+entry_hwirq:
+ ENTRY handle_hwirq
- .org 0xe739
- IRQ_ENTRY 14
-
- .org 0xe82e
- IRQ_ENTRY 16
-
- .org 0xe987
+ ORG 0xe987
IRQ_ENTRY 09
- .org 0xec59
- IRQ_ENTRY 40
+ ORG 0xec59
+ IRQ_ENTRY_ARG 40
- .org 0xef57
+ ORG 0xef57
IRQ_ENTRY 0e
- .org 0xefc7
+ ORG 0xefc7
.include "out/floppy_dbt.proc.16.s"
.text
- .org 0xefd2
- IRQ_ENTRY 17
+ ORG 0xefd2
+ IRQ_ENTRY_ARG 17
- .org 0xf045
+ ORG 0xf045
// XXX int 10
iretw
- .org 0xf065
- IRQ_ENTRY 10
+ ORG 0xf065
+ IRQ_ENTRY_ARG 10
- .org 0xf0a4
+ ORG 0xf0a4
// XXX int 1D
iretw
- .globl freespace2_start, freespace2_end
+ .global freespace2_start, freespace2_end
freespace2_start:
- .org 0xf841
+ ORG 0xf841
freespace2_end:
jmp entry_12
- .org 0xf84d
+ ORG 0xf84d
jmp entry_11
- .org 0xf859
- IRQ_ENTRY 15
+ ORG 0xf859
+ IRQ_ENTRY_ARG 15
- .org 0xfa6e
+ ORG 0xfa6e
.include "out/font.proc.16.s"
.text
- .org 0xfe6e
- IRQ_ENTRY 1a
+ ORG 0xfe6e
+ IRQ_ENTRY_ARG 1a
- .org 0xfea5
+ ORG 0xfea5
IRQ_ENTRY 08
- .org 0xfef3
+ ORG 0xfef3
// XXX - Initial Interrupt Vector Offsets Loaded by POST
- .org 0xff00
+ ORG 0xff00
// XXX - BIOS_COPYRIGHT_STRING
.ascii "(c) 2002 MandrakeSoft S.A. Written by Kevin Lawton & the Bochs team."
- .org 0xff53
- .globl dummy_iret_handler
+ ORG 0xff53
+ .global dummy_iret_handler
dummy_iret_handler:
iretw
- .org 0xff54
- IRQ_ENTRY 05
+ ORG 0xff54
+ IRQ_ENTRY_ARG 05
- .org 0xfff0 // Power-up Entry Point
- ljmpw $0xf000, $post16
+ ORG 0xfff0 // Power-up Entry Point
+ ljmpw $SEG_BIOS, $post16
- .org 0xfff5
+ ORG 0xfff5
// BIOS build date
.ascii "06/23/99"
- .org 0xfffe
+ ORG 0xfffe
.byte CONFIG_MODEL_ID
+
+ .global bios_checksum
+bios_checksum:
.byte 0x00
.end
projects / seabios.git / blobdiff