pci_cfgspace.c revision 7b3700d1667b1178db936c8f0864fe50a502417e
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/*
* PCI configuration space access routines
*/
#include <sys/systm.h>
#include <sys/psw.h>
#include <sys/bootconf.h>
#include <sys/reboot.h>
#include <sys/pci_impl.h>
#include <sys/pci_cfgspace.h>
#include <sys/pci_cfgspace_impl.h>
int pci_bios_cfg_type = PCI_MECHANISM_UNKNOWN;
int pci_bios_nbus;
int pci_bios_mech;
int pci_bios_vers;
/*
* These two variables can be used to force a configuration mechanism or
* to force which function is used to probe for the presence of the PCI bus.
*/
int PCI_CFG_TYPE = 0;
int PCI_PROBE_TYPE = 0;
/*
* These function pointers lead to the actual implementation routines
* for configuration space access. Normally they lead to either the
* pci_mech1_* or pci_mech2_* routines, but they can also lead to
* routines that work around chipset bugs.
*/
uint8_t (*pci_getb_func)(int bus, int dev, int func, int reg);
uint16_t (*pci_getw_func)(int bus, int dev, int func, int reg);
uint32_t (*pci_getl_func)(int bus, int dev, int func, int reg);
void (*pci_putb_func)(int bus, int dev, int func, int reg, uint8_t val);
void (*pci_putw_func)(int bus, int dev, int func, int reg, uint16_t val);
void (*pci_putl_func)(int bus, int dev, int func, int reg, uint32_t val);
/*
* Internal routines
*/
static int pci_check(void);
static int pci_check_bios(void);
static int pci_get_cfg_type(void);
/* all config-space access routines share this one... */
kmutex_t pcicfg_mutex;
/* ..except Orion and Neptune, which have to have their own */
kmutex_t pcicfg_chipset_mutex;
void
pci_cfgspace_init(void)
{
mutex_init(&pcicfg_mutex, NULL, MUTEX_SPIN,
(ddi_iblock_cookie_t)ipltospl(15));
mutex_init(&pcicfg_chipset_mutex, NULL, MUTEX_SPIN,
(ddi_iblock_cookie_t)ipltospl(15));
if (!pci_check()) {
mutex_destroy(&pcicfg_mutex);
mutex_destroy(&pcicfg_chipset_mutex);
}
}
/*
* This code determines if this system supports PCI and which
* type of configuration access method is used
*/
static int
pci_check(void)
{
/*
* Only do this once. NB: If this is not a PCI system, and we
* get called twice, we can't detect it and will probably die
* horribly when we try to ask the BIOS whether PCI is present.
* This code is safe *ONLY* during system startup when the
* BIOS is still available.
*/
if (pci_bios_cfg_type != PCI_MECHANISM_UNKNOWN)
return (TRUE);
pci_bios_cfg_type = pci_check_bios();
if (pci_bios_cfg_type == PCI_MECHANISM_NONE)
pci_bios_cfg_type = PCI_MECHANISM_1; /* default to mech 1 */
switch (pci_get_cfg_type()) {
case PCI_MECHANISM_1:
if (pci_is_broken_orion()) {
pci_getb_func = pci_orion_getb;
pci_getw_func = pci_orion_getw;
pci_getl_func = pci_orion_getl;
pci_putb_func = pci_orion_putb;
pci_putw_func = pci_orion_putw;
pci_putl_func = pci_orion_putl;
} else {
pci_getb_func = pci_mech1_getb;
pci_getw_func = pci_mech1_getw;
pci_getl_func = pci_mech1_getl;
pci_putb_func = pci_mech1_putb;
pci_putw_func = pci_mech1_putw;
pci_putl_func = pci_mech1_putl;
}
break;
case PCI_MECHANISM_2:
if (pci_check_neptune()) {
/*
* The BIOS for some systems with the Intel
* Neptune chipset seem to default to #2 even
* though the chipset can do #1. Override
* the BIOS so that MP systems will work
* correctly.
*/
pci_getb_func = pci_neptune_getb;
pci_getw_func = pci_neptune_getw;
pci_getl_func = pci_neptune_getl;
pci_putb_func = pci_neptune_putb;
pci_putw_func = pci_neptune_putw;
pci_putl_func = pci_neptune_putl;
} else {
pci_getb_func = pci_mech2_getb;
pci_getw_func = pci_mech2_getw;
pci_getl_func = pci_mech2_getl;
pci_putb_func = pci_mech2_putb;
pci_putw_func = pci_mech2_putw;
pci_putl_func = pci_mech2_putl;
}
break;
default:
return (FALSE);
}
return (TRUE);
}
static int
pci_check_bios(void)
{
struct bop_regs regs;
uint32_t carryflag;
uint16_t ax, dx;
bzero(&regs, sizeof (regs));
regs.eax.word.ax = (PCI_FUNCTION_ID << 8) | PCI_BIOS_PRESENT;
BOP_DOINT(bootops, 0x1a, &regs);
carryflag = regs.eflags & PS_C;
ax = regs.eax.word.ax;
dx = regs.edx.word.dx;
/* the carry flag must not be set */
if (carryflag != 0)
return (PCI_MECHANISM_NONE);
if (dx != ('P' | 'C'<<8))
return (PCI_MECHANISM_NONE);
/* ah (the high byte of ax) must be zero */
if ((ax & 0xff00) != 0)
return (PCI_MECHANISM_NONE);
pci_bios_mech = (ax & 0x3);
pci_bios_vers = regs.ebx.word.bx;
pci_bios_nbus = (regs.ecx.word.cx & 0xff);
switch (pci_bios_mech) {
default: /* ?!? */
case 0: /* supports neither? */
return (PCI_MECHANISM_NONE);
case 1:
case 3: /* supports both */
return (PCI_MECHANISM_1);
case 2:
return (PCI_MECHANISM_2);
}
}
static int
pci_get_cfg_type(void)
{
/* Check to see if the config mechanism has been set in /etc/system */
switch (PCI_CFG_TYPE) {
default:
case 0:
break;
case 1:
return (PCI_MECHANISM_1);
case 2:
return (PCI_MECHANISM_2);
case -1:
return (PCI_MECHANISM_NONE);
}
/* call one of the PCI detection algorithms */
switch (PCI_PROBE_TYPE) {
default:
case 0:
/* From pci_check() and pci_check_bios() */
return (pci_bios_cfg_type);
case -1:
return (PCI_MECHANISM_NONE);
}
}