diff --git a/src/arch/i386/include/comboot.h b/src/arch/i386/include/comboot.h index b5b1f8a0..56661a80 100644 --- a/src/arch/i386/include/comboot.h +++ b/src/arch/i386/include/comboot.h @@ -57,6 +57,40 @@ typedef struct { com32_reg32_t eflags; /* Offset 40 */ } com32sys_t; +typedef struct { + uint32_t eax; /* Offset 0 */ + uint32_t ecx; /* Offset 4 */ + uint32_t edx; /* Offset 8 */ + uint32_t ebx; /* Offset 12 */ + uint32_t esp; /* Offset 16 */ + uint32_t ebp; /* Offset 20 */ + uint32_t esi; /* Offset 24 */ + uint32_t edi; /* Offset 28 */ + + uint32_t eip; /* Offset 32 */ +} syslinux_pm_regs; + +typedef struct { + uint16_t es; /* Offset 0 */ + uint16_t _unused_cs; /* Offset 2 */ + uint16_t ds; /* Offset 4 */ + uint16_t ss; /* Offset 6 */ + uint16_t fs; /* Offset 8 */ + uint16_t gs; /* Offset 10 */ + + uint32_t eax; /* Offset 12 */ + uint32_t ecx; /* Offset 16 */ + uint32_t edx; /* Offset 20 */ + uint32_t ebx; /* Offset 24 */ + uint32_t esp; /* Offset 28 */ + uint32_t ebp; /* Offset 32 */ + uint32_t esi; /* Offset 36 */ + uint32_t edi; /* Offset 40 */ + + uint16_t ip; /* Offset 44 */ + uint16_t cs; /* Offset 46 */ +} syslinux_rm_regs; + typedef struct { uint32_t dest; uint32_t src; diff --git a/src/arch/i386/interface/syslinux/comboot_call.c b/src/arch/i386/interface/syslinux/comboot_call.c index 290d94ac..bf6c4c66 100644 --- a/src/arch/i386/interface/syslinux/comboot_call.c +++ b/src/arch/i386/interface/syslinux/comboot_call.c @@ -53,6 +53,14 @@ static char __data16_array ( syslinux_configuration_file, [] ) = ""; static uint8_t __data16 ( comboot_feature_flags ) = COMBOOT_FEATURE_IDLE_LOOP; #define comboot_feature_flags __use_data16 ( comboot_feature_flags ) +typedef union { + syslinux_pm_regs pm; syslinux_rm_regs rm; +} syslinux_regs; + +/** Initial register values for INT 22h AX=1Ah and 1Bh */ +static syslinux_regs __text16 ( comboot_initial_regs ); +#define comboot_initial_regs __use_text16 ( comboot_initial_regs ) + static struct segoff __text16 ( int20_vector ); #define int20_vector __use_text16 ( int20_vector ) @@ -316,7 +324,7 @@ static __asmcall void int22 ( struct i386_all_regs *ix86 ) { case 0x0001: /* Get Version */ /* Number of INT 22h API functions available */ - ix86->regs.ax = 0x0018; + ix86->regs.ax = 0x001B; /* SYSLINUX version number */ ix86->regs.ch = 0; /* major */ @@ -569,6 +577,58 @@ static __asmcall void int22 ( struct i386_all_regs *ix86 ) { ix86->flags &= ~CF; break; + case 0x001B: /* Cleanup, shuffle and boot to real mode */ + if ( ix86->regs.cx > COMBOOT_MAX_SHUFFLE_DESCRIPTORS ) + break; + + /* Perform final cleanup */ + shutdown ( SHUTDOWN_BOOT ); + + /* Perform sequence of copies */ + shuffle ( ix86->segs.es, ix86->regs.di, ix86->regs.cx ); + + /* Copy initial register values to .text16 */ + memcpy_user ( real_to_user ( rm_cs, (unsigned) __from_text16 ( &comboot_initial_regs ) ), 0, + real_to_user ( ix86->segs.ds, ix86->regs.si ), 0, + sizeof(syslinux_rm_regs) ); + + /* Load initial register values */ + __asm__ __volatile__ ( + REAL_CODE ( + /* Point SS:SP at the register value structure */ + "pushw %%cs\n\t" + "popw %%ss\n\t" + "movw $comboot_initial_regs, %%sp\n\t" + + /* Segment registers */ + "popw %%es\n\t" + "popw %%ax\n\t" /* Skip CS */ + "popw %%ds\n\t" + "popw %%ax\n\t" /* Skip SS for now */ + "popw %%fs\n\t" + "popw %%gs\n\t" + + /* GP registers */ + "popl %%eax\n\t" + "popl %%ecx\n\t" + "popl %%edx\n\t" + "popl %%ebx\n\t" + "popl %%ebp\n\t" /* Skip ESP for now */ + "popl %%ebp\n\t" + "popl %%esi\n\t" + "popl %%edi\n\t" + + /* Load correct SS:ESP */ + "movw $(comboot_initial_regs + 6), %%sp\n\t" + "popw %%ss\n\t" + "movl %%cs:(comboot_initial_regs + 28), %%esp\n\t" + + "ljmp *%%cs:(comboot_initial_regs + 44)\n\t" + ) + : : ); + + break; + default: DBG ( "COMBOOT unknown int22 function %04x\n", ix86->regs.ax ); break;