// Rom layout and bios assembler to C interface.
//
-// Copyright (C) 2008 Kevin O'Connor <kevin@koconnor.net>
+// Copyright (C) 2008,2009 Kevin O'Connor <kevin@koconnor.net>
// Copyright (C) 2002 MandrakeSoft S.A.
//
// This file may be distributed under the terms of the GNU LGPLv3 license.
-#include "config.h" // CONFIG_*
-#include "ioport.h" // PORT_A20
-#include "bregs.h" // CR0_*
-#include "cmos.h" // CMOS_RESET_CODE
-#include "../out/asm-offsets.h" // BREGS_*
-
/****************************************************************
* Include of 16bit C code
.code16gcc
.include "out/ccode.16.s"
-
-/****************************************************************
- * 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 $ BUILD_STACK_ADDR , %esp
- cld
- .endm
-
- // Declare a function
- .macro DECLFUNC func
- .section .text.asm.\func
- .global \func
- .endm
-
-
-/****************************************************************
- * POST handler
- ****************************************************************/
-
- DECLFUNC entry_post
-entry_post:
- // enable cache
- movl %cr0, %eax
- andl $~(CR0_CD|CR0_NW), %eax
- movl %eax, %cr0
-
- // Check for restart indicator.
- movl $CMOS_RESET_CODE, %eax
- outb %al, $PORT_CMOS_INDEX
- inb $PORT_CMOS_DATA, %al
- cmpb $0x0, %al
- jnz 1f
-
- // Normal entry point
- RESET_STACK
- pushl $_code32__start
- jmp transition32
-
- // Entry point when a post call looks like a resume.
-1:
- // Save old shutdown status.
- movl %eax, %ebx
-
- // Clear shutdown status register.
- movl $CMOS_RESET_CODE, %eax
- outb %al, $PORT_CMOS_INDEX
- xorl %eax, %eax
- outb %al, $PORT_CMOS_DATA
-
- // Use a stack in EBDA
- movw $SEG_BDA, %ax
- movw %ax, %ds
- movw BDA_ebda_seg, %ax
- // XXX - should verify ebda_seg looks sane.
- movw %ax, %ds
- movw %ax, %ss
- movl $EBDA_OFFSET_TOP_STACK, %esp
-
- // Call handler.
- movl %ebx, %eax
- cld
- cli
- jmp handle_resume
+#include "config.h" // CONFIG_*
+#include "ioport.h" // PORT_A20
+#include "bregs.h" // CR0_*
+#include "cmos.h" // CMOS_RESET_CODE
+#include "../out/asm-offsets.h" // BREGS_*
+#include "entryfuncs.S" // ENTRY_*
/****************************************************************
****************************************************************/
// Place CPU into 32bit mode from 16bit mode.
-// Clobbers: %eax, flags, stack registers, cr0, idt/gdt
+// Clobbers: flags, segment registers, cr0, idt/gdt
DECLFUNC transition32
transition32:
- // Disable irqs
+ pushl %eax
+
+ // Disable irqs (and clear direction flag)
cli
+ cld
+
+ // Disable nmi
+ movl $CMOS_RESET_CODE|NMI_DISABLE_BIT, %eax
+ outb %al, $PORT_CMOS_INDEX
+ inb $PORT_CMOS_DATA, %al
// enable a20
inb $PORT_A20, %al
movw %ax, %fs
movw %ax, %gs
+ popl %eax
retl
// Call a 16bit function from 32bit mode.
// %eax = address of struct bregs
-// Clobbers: all gp registers, flags, stack registers, cr0, idt/gdt
+// Clobbers: %e[bcd]x, %e[ds]i, flags, segment registers, idt/gdt
DECLFUNC __call16_from32
.global __call16big_from32
__call16_from32:
movw %ax, %fs
movw %ax, %gs
+#if CONFIG_DISABLE_A20
// disable a20
inb $PORT_A20, %al
andb $~A20_ENABLE_BIT, %al
outb %al, $PORT_A20
+#endif
// Jump to 16bit mode
ljmpw $SEG32_MODE16_CS, $1f
// Call a 16bit function from 16bit mode with a specified cpu register state
// %eax = address of struct bregs
-// Clobbers: all gp registers, es
+// Clobbers: %e[bcd]x, %e[ds]i, flags
DECLFUNC __call16
__call16:
- // Save eax
+ // Save %eax, %ebp
+ pushl %ebp
pushl %eax
// Setup for iretw call
// Load calling registers.
movl BREGS_edi(%eax), %edi
movl BREGS_esi(%eax), %esi
+ movl BREGS_ebp(%eax), %ebp
movl BREGS_ebx(%eax), %ebx
movl BREGS_edx(%eax), %edx
movl BREGS_ecx(%eax), %ecx
movw %es, BREGS_es(%eax)
movl %edi, BREGS_edi(%eax)
movl %esi, BREGS_esi(%eax)
+ movl %ebp, BREGS_ebp(%eax)
movl %ebx, BREGS_ebx(%eax)
movl %edx, BREGS_edx(%eax)
- // Remove %eax
+ // Remove %eax, restore %ebp
popl %eax
+ popl %ebp
+
+ retl
+
+// IRQ trampolines
+ .macro IRQ_TRAMPOLINE num
+ DECLFUNC irq_trampoline_0x\num
+ irq_trampoline_0x\num :
+ int $0x\num
+ lretw
+ .endm
+
+ IRQ_TRAMPOLINE 10
+ IRQ_TRAMPOLINE 13
+ IRQ_TRAMPOLINE 15
+ IRQ_TRAMPOLINE 16
+ IRQ_TRAMPOLINE 18
+ IRQ_TRAMPOLINE 19
+
+/****************************************************************
+ * POST entry point
+ ****************************************************************/
+
+ DECLFUNC entry_post
+entry_post:
+ // Enable cache
+ movl %cr0, %eax
+ andl $~(CR0_CD|CR0_NW), %eax
+ movl %eax, %cr0
+
+ // Disable interrupts
+ cli
cld
- retl
+ // Check for restart indicator.
+ movl $CMOS_RESET_CODE|NMI_DISABLE_BIT, %eax
+ outb %al, $PORT_CMOS_INDEX
+ inb $PORT_CMOS_DATA, %al
+ cmpb $0x0, %al
+ jnz 1f
+
+ // Normal entry point
+ ENTRY_INTO32 _start
+
+ // Entry point when a post call looks like a resume.
+1:
+ // Save old shutdown status.
+ movl %eax, %ebx
-// PnP trampolines
+ // Clear shutdown status register.
+ movl $CMOS_RESET_CODE|NMI_DISABLE_BIT, %eax
+ outb %al, $PORT_CMOS_INDEX
+ xorl %eax, %eax
+ outb %al, $PORT_CMOS_DATA
+
+ // Use a stack in EBDA
+ movw $SEG_BDA, %ax
+ movw %ax, %ds
+ movw BDA_ebda_seg, %ax
+
+ cmpw $EBDA_SEGMENT_START, %ax
+ jle 2f
+ // EBDA segment doesn't look valid - use startup value.
+ movw $EBDA_SEGMENT_START, %ax
+
+2: movw %ax, %ds
+ movw %ax, %ss
+ movl $EBDA_OFFSET_TOP_STACK, %esp
+
+ // Call handler.
+ movl %ebx, %eax
+ jmp handle_resume
+
+
+/****************************************************************
+ * Misc. entry points.
+ ****************************************************************/
+
+// PnP entry points
DECLFUNC entry_pnp_real
.global entry_pnp_prot
entry_pnp_prot:
popl %esp
lretw
-// APM trampolines
+// APM entry points
DECLFUNC apm16protected_entry
apm16protected_entry:
pushfw // save flags
lretl
// 32bit elf entry point
- DECLFUNC post32
+ EXPORTFUNC post32
post32:
cli
cld
lidtl (BUILD_BIOS_ADDR + pmode_IDT_info)
lgdtl (BUILD_BIOS_ADDR + rombios32_gdt_48)
+ movl $SEG32_MODE32_DS, %eax
+ movw %ax, %ds
+ movw %ax, %es
+ movw %ax, %fs
+ movw %ax, %gs
+ movw %ax, %ss
movl $BUILD_STACK_ADDR, %esp
- ljmpl $SEG32_MODE32_CS, $_code32__start
+ ljmpl $SEG32_MODE32_CS, $_start
.code16gcc
-// Shutdown a CPU. We want this in the 0xf000 section to ensure that
-// the code wont be overwritten with something else. (Should
-// something spurious wake up the CPU, we want to be sure that the hlt
-// insn will still be present and will shutdown the CPU.)
- DECLFUNC permanent_halt
-permanent_halt:
- cli
-1: hlt
- jmp 1b
-
- // IRQ trampolines
- .macro IRQ_TRAMPOLINE num
- DECLFUNC irq_trampoline_0x\num
- irq_trampoline_0x\num :
- int $0x\num
- lretw
- .endm
-
- IRQ_TRAMPOLINE 10
- IRQ_TRAMPOLINE 13
- IRQ_TRAMPOLINE 15
- IRQ_TRAMPOLINE 16
- IRQ_TRAMPOLINE 18
- IRQ_TRAMPOLINE 19
-
/****************************************************************
* Interrupt entry points
.macro IRQ_ENTRY num
.global entry_\num
entry_\num :
- cli // In case something far-calls instead of using "int"
- ENTRY handle_\num
- iretw
+ pushl $ handle_\num
+ jmp irqentry
.endm
// 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
+ pushl $ handle_\num
+ jmp irqentryarg
.endm
// Macros that put each handler into its own section
.macro DECL_IRQ_ENTRY num
- .section .text.asm.entry_\num
+ DECLFUNC entry_\num
IRQ_ENTRY \num
.endm
.macro DECL_IRQ_ENTRY_ARG num
- .section .text.asm.entry_\num
+ DECLFUNC entry_\num
IRQ_ENTRY_ARG \num
.endm
+ // Main entry point for interrupts without args
+ DECLFUNC irqentry
+irqentry:
+ ENTRY_ST
+ iretw
+
+ // Main entry point for interrupts with args
+ DECLFUNC irqentryarg
+irqentryarg:
+ ENTRY_ARG_ST
+ iretw
+
DECL_IRQ_ENTRY_ARG 13
- DECL_IRQ_ENTRY_ARG 12
- DECL_IRQ_ENTRY_ARG 11
DECL_IRQ_ENTRY 76
DECL_IRQ_ENTRY 70
DECL_IRQ_ENTRY 74
DECL_IRQ_ENTRY hwpic1
DECL_IRQ_ENTRY hwpic2
- // int 18/19 are special - they reset the stack and do not return.
+ // int 18/19 are special - they reset stack and call into 32bit mode.
DECLFUNC entry_19
entry_19:
- RESET_STACK
- pushl $_code32_handle_19
- jmp transition32
+ ENTRY_INTO32 handle_19
DECLFUNC entry_18
entry_18:
- RESET_STACK
- pushl $_code32_handle_18
- jmp transition32
+ ENTRY_INTO32 handle_18
/****************************************************************
jmp entry_post
ORG 0xe2c3
- IRQ_ENTRY nmi
+ IRQ_ENTRY 02
ORG 0xe3fe
.global entry_13_official
// 0xf0a4 - VideoParams in misc.c
ORG 0xf841
- .global entry_12_official
-entry_12_official:
- jmp entry_12
+ IRQ_ENTRY_ARG 12
ORG 0xf84d
- .global entry_11_official
-entry_11_official:
- jmp entry_11
+ IRQ_ENTRY_ARG 11
ORG 0xf859
IRQ_ENTRY_ARG 15
projects / seabios.git / blobdiff