blob: c8bc8f44579209d1577adadfc58467d030947354 [file] [log] [blame]
// PNP BIOS calls
//
// Copyright (C) 2008 Kevin O'Connor <kevin@koconnor.net>
//
// This file may be distributed under the terms of the GNU LGPLv3 license.
#include "util.h" // checksum
#include "config.h" // BUILD_BIOS_ADDR
#include "farptr.h" // SET_FARVAR
struct pnpheader {
u32 signature;
u8 version;
u8 length;
u16 control;
u8 checksum;
u32 eventloc;
u16 real_ip;
u16 real_cs;
u16 prot_ip;
u32 prot_base;
u32 oemid;
u16 real_ds;
u32 prot_database;
} PACKED;
extern struct pnpheader PNPHEADER;
extern char pnp_string[];
#if CONFIG_PNPBIOS
struct pnpheader PNPHEADER __aligned(16) VAR16EXPORT = {
.signature = PNP_SIGNATURE,
.version = 0x10,
.length = sizeof(PNPHEADER),
.real_cs = SEG_BIOS,
.prot_base = BUILD_BIOS_ADDR,
.real_ds = SEG_BIOS,
.prot_database = BUILD_BIOS_ADDR,
};
#else
// We need a copy of this string in the 0xf000 segment, but we are not
// actually a PnP BIOS, so make sure it is *not* aligned, so OSes will
// not see it if they scan.
char pnp_string[] __aligned(2) VAR16VISIBLE = " $PnP";
#endif
#define FUNCTION_NOT_SUPPORTED 0x82
// BBS - Get Version and Installation Check
static u16
handle_pnp60(u16 *args)
{
u16 version_ptr = args[1];
u16 version_seg = args[2];
SET_FARVAR(version_seg, *(u16*)(version_ptr+0), 0x0101);
return 0;
}
static u16
handle_pnpXX(u16 *args)
{
return FUNCTION_NOT_SUPPORTED;
}
u16 VISIBLE16
handle_pnp(u16 *args)
{
if (! CONFIG_PNPBIOS)
return FUNCTION_NOT_SUPPORTED;
u16 arg1 = args[0];
dprintf(DEBUG_HDL_pnp, "pnp call arg1=%x\n", arg1);
switch (arg1) {
case 0x60: return handle_pnp60(args);
default: return handle_pnpXX(args);
}
}
u16
get_pnp_offset(void)
{
if (! CONFIG_PNPBIOS)
return (u32)pnp_string + 1 - BUILD_BIOS_ADDR;
return (u32)&PNPHEADER - BUILD_BIOS_ADDR;
}
// romlayout.S
extern void entry_pnp_real(void);
extern void entry_pnp_prot(void);
void
pnp_init(void)
{
if (! CONFIG_PNPBIOS)
return;
dprintf(3, "init PNPBIOS table\n");
PNPHEADER.real_ip = (u32)entry_pnp_real - BUILD_BIOS_ADDR;
PNPHEADER.prot_ip = (u32)entry_pnp_prot - BUILD_BIOS_ADDR;
PNPHEADER.checksum -= checksum(&PNPHEADER, sizeof(PNPHEADER));
}