* Copyright (c) 1998, 2000, 2020 The NetBSD Foundation, Inc.

/* $NetBSD: pci_map.c,v 1.44 2020/12/29 15:49:45 skrll Exp $ */

/*-
* Copyright (c) 1998, 2000, 2020 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Charles M. Hannum; by William R. Studenmund; by Jason R. Thorpe.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/

/*
* PCI device mapping.
*/

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: pci_map.c,v 1.44 2020/12/29 15:49:45 skrll Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>

#include <dev/pci/pcireg.h>
#include <dev/pci/pcivar.h>

bool pci_mapreg_map_enable_decode = true;

static int
pci_io_find(pci_chipset_tag_t pc, pcitag_t tag, int reg, pcireg_t type,
bus_addr_t *basep, bus_size_t *sizep, int *flagsp)
{
pcireg_t address, mask, csr;
int s;

if (reg < PCI_MAPREG_START ||
#if 0
/*
* Can't do this check; some devices have mapping registers
* way out in left field.
*/
reg >= PCI_MAPREG_END ||
#endif
(reg & 3))
panic("pci_io_find: bad request");

/*
* Section 6.2.5.1, `Address Maps', tells us that:
*
* 1) The builtin software should have already mapped the device in a
* reasonable way.
*
* 2) A device which wants 2^n bytes of memory will hardwire the bottom
* n bits of the address to 0. As recommended, we write all 1s and see
* what we get back.
*/
s = splhigh();
address = pci_conf_read(pc, tag, reg);
/*
* Disable decoding via the command register before writing to the
* BAR register. Changing the decoding address to all-one is
* not a valid address and could have side effects.
*/
csr = pci_conf_read(pc, tag, PCI_COMMAND_STATUS_REG);
pci_conf_write(pc, tag, PCI_COMMAND_STATUS_REG,
csr & ~PCI_COMMAND_IO_ENABLE) ;
pci_conf_write(pc, tag, reg, 0xffffffff);
mask = pci_conf_read(pc, tag, reg);
pci_conf_write(pc, tag, reg, address);
pci_conf_write(pc, tag, PCI_COMMAND_STATUS_REG, csr);
splx(s);

if (PCI_MAPREG_TYPE(address) != PCI_MAPREG_TYPE_IO) {
aprint_debug("pci_io_find: expected type i/o, found mem\n");
return 1;
}

if (PCI_MAPREG_IO_SIZE(mask) == 0) {
aprint_debug("pci_io_find: void region\n");
return 1;
}

if (basep != NULL)
*basep = PCI_MAPREG_IO_ADDR(address);
if (sizep != NULL)
*sizep = PCI_MAPREG_IO_SIZE(mask);
if (flagsp != NULL)
*flagsp = 0;

return 0;
}

static int
pci_mem_find(pci_chipset_tag_t pc, pcitag_t tag, int reg, pcireg_t type,
bus_addr_t *basep, bus_size_t *sizep, int *flagsp)
{
pcireg_t address, mask, address1 = 0, mask1 = 0xffffffff;
uint64_t waddress, wmask;
int s, is64bit, isrom;
pcireg_t csr;

is64bit = (PCI_MAPREG_MEM_TYPE(type) == PCI_MAPREG_MEM_TYPE_64BIT);
isrom = (reg == PCI_MAPREG_ROM);

if ((!isrom) && (reg < PCI_MAPREG_START ||
#if 0
/*
* Can't do this check; some devices have mapping registers
* way out in left field.
*/
reg >= PCI_MAPREG_END ||
#endif
(reg & 3)))
panic("pci_mem_find: bad request");

if (is64bit && (reg + 4) >= PCI_MAPREG_END)
panic("pci_mem_find: bad 64-bit request");

/*
* Section 6.2.5.1, `Address Maps', tells us that:
*
* 1) The builtin software should have already mapped the device in a
* reasonable way.
*
* 2) A device which wants 2^n bytes of memory will hardwire the bottom
* n bits of the address to 0. As recommended, we write all 1s and see
* what we get back. Only probe the upper BAR of a mem64 BAR if bit 31
* is readonly.
*/
s = splhigh();
address = pci_conf_read(pc, tag, reg);
csr = pci_conf_read(pc, tag, PCI_COMMAND_STATUS_REG);
/*
* Disable decoding via the command register before writing to the
* BAR register. Changing the decoding address to all-one is
* not a valid address and could have side effects.
*/
pci_conf_write(pc, tag, PCI_COMMAND_STATUS_REG,
csr & ~PCI_COMMAND_MEM_ENABLE) ;
pci_conf_write(pc, tag, reg, 0xffffffff);
mask = pci_conf_read(pc, tag, reg);
pci_conf_write(pc, tag, reg, address);
if (is64bit) {
address1 = pci_conf_read(pc, tag, reg + 4);
if ((mask & 0x80000000) == 0) {
pci_conf_write(pc, tag, reg + 4, 0xffffffff);
mask1 = pci_conf_read(pc, tag, reg + 4);
pci_conf_write(pc, tag, reg + 4, address1);
}
}
pci_conf_write(pc, tag, PCI_COMMAND_STATUS_REG, csr);
splx(s);

if (!isrom) {
/*
* roms should have an enable bit instead of a memory
* type decoder bit. For normal BARs, make sure that
* the address decoder type matches what we asked for.
*/
if (PCI_MAPREG_TYPE(address) != PCI_MAPREG_TYPE_MEM) {
printf("pci_mem_find: expected type mem, found i/o\n");
return 1;
}
/* XXX Allow 64bit bars for 32bit requests.*/
if (PCI_MAPREG_MEM_TYPE(address) !=
PCI_MAPREG_MEM_TYPE(type) &&
PCI_MAPREG_MEM_TYPE(address) !=
PCI_MAPREG_MEM_TYPE_64BIT) {
printf("pci_mem_find: "
"expected mem type %08x, found %08x\n",
PCI_MAPREG_MEM_TYPE(type),
PCI_MAPREG_MEM_TYPE(address));
return 1;
}
}

waddress = (uint64_t)address1 << 32UL | address;
wmask = (uint64_t)mask1 << 32UL | mask;

if ((is64bit && PCI_MAPREG_MEM64_SIZE(wmask) == 0) ||
(!is64bit && PCI_MAPREG_MEM_SIZE(mask) == 0)) {
aprint_debug("pci_mem_find: void region\n");
return 1;
}

switch (PCI_MAPREG_MEM_TYPE(address)) {
case PCI_MAPREG_MEM_TYPE_32BIT:
case PCI_MAPREG_MEM_TYPE_32BIT_1M:
break;
case PCI_MAPREG_MEM_TYPE_64BIT:
/*
* Handle the case of a 64-bit memory register on a
* platform with 32-bit addressing. Make sure that
* the address assigned and the device's memory size
* fit in 32 bits. We implicitly assume that if
* bus_addr_t is 64-bit, then so is bus_size_t.
*/
if (sizeof(uint64_t) > sizeof(bus_addr_t) &&
(address1 != 0 || mask1 != 0xffffffff)) {
printf("pci_mem_find: 64-bit memory map which is "
"inaccessible on a 32-bit platform\n");
return 1;
}
break;
default:
printf("pci_mem_find: reserved mapping register type\n");
return 1;
}

if (sizeof(uint64_t) > sizeof(bus_addr_t)) {
if (basep != NULL)
*basep = PCI_MAPREG_MEM_ADDR(address);
if (sizep != NULL)
*sizep = PCI_MAPREG_MEM_SIZE(mask);
} else {
if (basep != NULL)
*basep = PCI_MAPREG_MEM64_ADDR(waddress);
if (sizep != NULL)
*sizep = PCI_MAPREG_MEM64_SIZE(wmask);
}
if (flagsp != NULL)
*flagsp = (isrom || PCI_MAPREG_MEM_PREFETCHABLE(address)) ?
BUS_SPACE_MAP_PREFETCHABLE : 0;

return 0;
}

static const char *
bar_type_string(pcireg_t type)
{
if (PCI_MAPREG_TYPE(type) == PCI_MAPREG_TYPE_IO)
return "IO";

switch (PCI_MAPREG_MEM_TYPE(type)) {
case PCI_MAPREG_MEM_TYPE_32BIT:
return "MEM32";
case PCI_MAPREG_MEM_TYPE_32BIT_1M:
return "MEM32-1M";
case PCI_MAPREG_MEM_TYPE_64BIT:
return "MEM64";
}
return "<UNKNOWN>";
}

enum {
EA_ptr_dw0 = 0,
EA_ptr_base_lower = 1,
EA_ptr_base_upper = 2,
EA_ptr_maxoffset_lower = 3,
EA_ptr_maxoffset_upper = 4,

EA_PTR_COUNT = 5
};

struct pci_ea_entry {
/* entry field pointers */
int ea_ptrs[EA_PTR_COUNT];

/* Raw register values. */
pcireg_t dw0;
pcireg_t base_lower;
pcireg_t base_upper;
pcireg_t maxoffset_lower;
pcireg_t maxoffset_upper;

/* Interesting tidbits derived from them. */
uint64_t base;
uint64_t maxoffset;
unsigned int bei;
unsigned int props[2];
bool base_is_64;
bool maxoffset_is_64;
bool enabled;
bool writable;
};

static int
pci_ea_lookup(pci_chipset_tag_t pc, pcitag_t tag, int ea_cap_ptr,
int reg, struct pci_ea_entry *entryp)
{
struct pci_ea_entry entry = {
.ea_ptrs[EA_ptr_dw0] = ea_cap_ptr + 4,
};
unsigned int i, num_entries;
unsigned int wanted_bei;
pcireg_t val;

if (reg >= PCI_BAR0 && reg <= PCI_BAR5)
wanted_bei = PCI_EA_BEI_BAR0 + ((reg - PCI_BAR0) / 4);
else if (reg == PCI_MAPREG_ROM)
wanted_bei = PCI_EA_BEI_EXPROM;
else {
/* Invalid BAR. */
return 1;
}

val = pci_conf_read(pc, tag, ea_cap_ptr + PCI_EA_CAP1);
num_entries = __SHIFTOUT(val, PCI_EA_CAP1_NUMENTRIES);

val = pci_conf_read(pc, tag, PCI_BHLC_REG);
if (PCI_HDRTYPE_TYPE(val) == PCI_HDRTYPE_PPB) {
/* Need to skip over PCI_EA_CAP2 on PPBs. */
entry.ea_ptrs[EA_ptr_dw0] += 4;
}

for (i = 0; i < num_entries; i++) {
val = pci_conf_read(pc, tag, entry.ea_ptrs[EA_ptr_dw0]);
unsigned int entry_size = __SHIFTOUT(val, PCI_EA_ES);

entry.bei = __SHIFTOUT(val, PCI_EA_BEI);
entry.props[0] = __SHIFTOUT(val, PCI_EA_PP);
entry.props[1] = __SHIFTOUT(val, PCI_EA_SP);
entry.writable = (val & PCI_EA_W) ? true : false;
entry.enabled = (val & PCI_EA_E) ? true : false;

if (entry.bei != wanted_bei || entry_size == 0) {
entry.ea_ptrs[EA_ptr_dw0] += 4 * (entry_size + 1);
continue;
}

entry.ea_ptrs[EA_ptr_base_lower] =
entry.ea_ptrs[EA_ptr_dw0] + 4;
entry.ea_ptrs[EA_ptr_maxoffset_lower] =
entry.ea_ptrs[EA_ptr_dw0] + 8;

/* Base */
entry.base_lower = pci_conf_read(pc, tag,
entry.ea_ptrs[EA_ptr_base_lower]);
entry.base_is_64 =
(entry.base_lower & PCI_EA_BASEMAXOFFSET_64BIT)
? true : false;
if (entry.base_is_64) {
entry.ea_ptrs[EA_ptr_base_upper] =
entry.ea_ptrs[EA_ptr_dw0] + 12;
entry.base_upper = pci_conf_read(pc, tag,
entry.ea_ptrs[EA_ptr_base_upper]);
} else {
entry.ea_ptrs[EA_ptr_base_upper] = 0;
entry.base_upper = 0;
}

entry.base = (entry.base_lower & PCI_EA_LOWMASK) |
((uint64_t)entry.base_upper << 32);

/* MaxOffset */
entry.maxoffset_lower = pci_conf_read(pc, tag,
entry.ea_ptrs[EA_ptr_maxoffset_lower]);
entry.maxoffset_is_64 =
(entry.maxoffset_lower & PCI_EA_BASEMAXOFFSET_64BIT)
? true : false;
if (entry.maxoffset_is_64) {
entry.ea_ptrs[EA_ptr_maxoffset_upper] =
entry.ea_ptrs[EA_ptr_dw0] +
(entry.base_is_64 ? 16 : 12);
entry.maxoffset_upper = pci_conf_read(pc, tag,
entry.ea_ptrs[EA_ptr_maxoffset_upper]);
} else {
entry.ea_ptrs[EA_ptr_maxoffset_upper] = 0;
entry.maxoffset_upper = 0;
}

entry.maxoffset = (entry.maxoffset_lower & PCI_EA_LOWMASK) |
((uint64_t)entry.maxoffset_upper << 32);

if (entryp)
*entryp = entry;
return 0;
}
return 1;
}

static int
pci_ea_find(pci_chipset_tag_t pc, pcitag_t tag, int ea_cap_ptr,
int reg, pcireg_t type, bus_addr_t *basep, bus_size_t *sizep, int *flagsp,
struct pci_ea_entry *entryp)
{

struct pci_ea_entry entry;
int rv = pci_ea_lookup(pc, tag, ea_cap_ptr, reg, &entry);
if (rv)
return rv;

pcireg_t wanted_type;
if (PCI_MAPREG_TYPE(type) == PCI_MAPREG_TYPE_IO)
wanted_type = PCI_MAPREG_TYPE_IO;
else {
/*
* This covers ROM as well. We allow any user-specified
* memory type to match an EA memory region with no regard
* for 32 vs. 64.
*
* XXX Should it?
*/
wanted_type = PCI_MAPREG_TYPE_MEM;
}

/*
* MaxOffset is the last offset where you can issue a
* 32-bit read in the region. Therefore, the size of
* the region is MaxOffset + 4.
*/
uint64_t region_size = entry.maxoffset + 4;

unsigned int which_prop;
for (which_prop = 0; which_prop < 2; which_prop++) {
int mapflags = 0;

switch (entry.props[which_prop]) {
case PCI_EA_PROP_MEM_PREF:
mapflags |= BUS_SPACE_MAP_PREFETCHABLE;
/* FALLTHROUGH */
case PCI_EA_PROP_MEM_NONPREF:
if (PCI_MAPREG_TYPE(wanted_type) != PCI_MAPREG_TYPE_MEM)
goto unexpected_type;
break;

case PCI_EA_PROP_IO:
if (PCI_MAPREG_TYPE(wanted_type) != PCI_MAPREG_TYPE_IO)
goto unexpected_type;
break;

case PCI_EA_PROP_MEM_UNAVAIL:
case PCI_EA_PROP_IO_UNAVAIL:
case PCI_EA_PROP_UNAVAIL:
return 1;

/* XXX Don't support these yet. */
case PCI_EA_PROP_VF_MEM_PREF:
case PCI_EA_PROP_VF_MEM_NONPREF:
case PCI_EA_PROP_BB_MEM_PREF:
case PCI_EA_PROP_BB_MEM_NONPREF:
case PCI_EA_PROP_BB_IO:
default:
printf("%s: bei %u props[%u]=0x%x\n",
__func__, entry.bei, which_prop,
entry.props[which_prop]);
continue;
continue;
}

if ((sizeof(uint64_t) > sizeof(bus_addr_t) ||
PCI_MAPREG_TYPE(wanted_type) == PCI_MAPREG_TYPE_IO) &&
(entry.base + region_size) > 0x100000000ULL) {
goto inaccessible_64bit_region;
}

*basep = (bus_addr_t)entry.base;
*sizep = (bus_size_t)region_size;
*flagsp = mapflags;
if (entryp)
*entryp = entry;
return 0;
}

/* BAR not found. */
return 1;

unexpected_type:
printf("%s: unexpected type; wanted %s, got 0x%02x\n",
__func__, bar_type_string(wanted_type), entry.props[which_prop]);
return 1;

inaccessible_64bit_region:
if (PCI_MAPREG_TYPE(wanted_type) == PCI_MAPREG_TYPE_IO) {
printf("%s: 64-bit IO regions are unsupported\n",
__func__);
return 1;
}
printf("%s: 64-bit memory region inaccessible on 32-bit platform\n",
__func__);
return 1;
}

#define _PCI_MAPREG_TYPEBITS(reg) \
(PCI_MAPREG_TYPE(reg) == PCI_MAPREG_TYPE_IO ? \
reg & PCI_MAPREG_TYPE_MASK : \
reg & (PCI_MAPREG_TYPE_MASK|PCI_MAPREG_MEM_TYPE_MASK))

pcireg_t
pci_mapreg_type(pci_chipset_tag_t pc, pcitag_t tag, int reg)
{

return _PCI_MAPREG_TYPEBITS(pci_conf_read(pc, tag, reg));
}

int
pci_mapreg_probe(pci_chipset_tag_t pc, pcitag_t tag, int reg, pcireg_t *typep)
{
pcireg_t address, mask, csr;
int s;

s = splhigh();
address = pci_conf_read(pc, tag, reg);
/*
* Disable decoding via the command register before writing to the
* BAR register. Changing the decoding address to all-one is
* not a valid address and could have side effects.
*/
csr = pci_conf_read(pc, tag, PCI_COMMAND_STATUS_REG);
if (PCI_MAPREG_TYPE(address) == PCI_MAPREG_TYPE_IO) {
pci_conf_write(pc, tag, PCI_COMMAND_STATUS_REG,
csr & ~PCI_COMMAND_IO_ENABLE);
} else {
pci_conf_write(pc, tag, PCI_COMMAND_STATUS_REG,
csr & ~PCI_COMMAND_MEM_ENABLE);
}
pci_conf_write(pc, tag, reg, 0xffffffff);
mask = pci_conf_read(pc, tag, reg);
pci_conf_write(pc, tag, reg, address);
pci_conf_write(pc, tag, PCI_COMMAND_STATUS_REG, csr);
splx(s);

if (mask == 0) /* unimplemented mapping register */
return 0;

if (typep != NULL)
*typep = _PCI_MAPREG_TYPEBITS(address);
return 1;
}

int
pci_mapreg_info(pci_chipset_tag_t pc, pcitag_t tag, int reg, pcireg_t type,
bus_addr_t *basep, bus_size_t *sizep, int *flagsp)
{
int ea_cap_ptr;

if (pci_get_capability(pc, tag, PCI_CAP_EA, &ea_cap_ptr, NULL))
return pci_ea_find(pc, tag, ea_cap_ptr, reg, type,
basep, sizep, flagsp, NULL);

if (PCI_MAPREG_TYPE(type) == PCI_MAPREG_TYPE_IO)
return pci_io_find(pc, tag, reg, type, basep, sizep,
flagsp);
else
return pci_mem_find(pc, tag, reg, type, basep, sizep,
flagsp);
}

int
pci_mapreg_map(const struct pci_attach_args *pa, int reg, pcireg_t type,
int busflags, bus_space_tag_t *tagp, bus_space_handle_t *handlep,
bus_addr_t *basep, bus_size_t *sizep)
{
return pci_mapreg_submap(pa, reg, type, busflags, 0, 0, tagp,
handlep, basep, sizep);
}

int
pci_mapreg_submap(const struct pci_attach_args *pa, int reg, pcireg_t type,
int busflags, bus_size_t reqsize, bus_size_t offset, bus_space_tag_t *tagp,
bus_space_handle_t *handlep, bus_addr_t *basep, bus_size_t *sizep)
{
bus_space_tag_t tag;
bus_space_handle_t handle;
bus_addr_t base;
bus_size_t realmaxsize;
pcireg_t csr;
int flags, s;
int ea_cap_ptr;
bool have_ea = false;
struct pci_ea_entry entry;

if (PCI_MAPREG_TYPE(type) == PCI_MAPREG_TYPE_IO) {
if ((pa->pa_flags & PCI_FLAGS_IO_OKAY) == 0)
return 1;
tag = pa->pa_iot;
} else {
if ((pa->pa_flags & PCI_FLAGS_MEM_OKAY) == 0)
return 1;
tag = pa->pa_memt;
}

if (pci_get_capability(pa->pa_pc, pa->pa_tag, PCI_CAP_EA, &ea_cap_ptr,
NULL)) {
have_ea = true;
if (pci_ea_find(pa->pa_pc, pa->pa_tag, ea_cap_ptr, reg, type,
&base, &realmaxsize, &flags, &entry))
return 1;
if (reg != PCI_MAPREG_ROM && !entry.enabled) {
/* Entry not enabled. Try the regular BAR? */
have_ea = false;
}
}

if (!have_ea) {
if (PCI_MAPREG_TYPE(type) == PCI_MAPREG_TYPE_IO) {
if (pci_io_find(pa->pa_pc, pa->pa_tag, reg, type,
&base, &realmaxsize, &flags))
return 1;
} else {
if (pci_mem_find(pa->pa_pc, pa->pa_tag, reg, type,
&base, &realmaxsize, &flags))
return 1;
}
}

if (reg == PCI_MAPREG_ROM) {
/* Enable the ROM address decoder, if necessary. */
if (have_ea) {
if (!entry.enabled) {
entry.dw0 |= PCI_EA_E;
pci_conf_write(pa->pa_pc, pa->pa_tag,
entry.ea_ptrs[EA_ptr_dw0],
entry.dw0);
entry.enabled = true;
}
} else {
s = splhigh();
pcireg_t mask =
pci_conf_read(pa->pa_pc, pa->pa_tag, reg);
if ((mask & PCI_MAPREG_ROM_ENABLE) == 0) {
mask |= PCI_MAPREG_ROM_ENABLE;
pci_conf_write(pa->pa_pc, pa->pa_tag, reg,
mask);
}
splx(s);
}
}

/*
* If we're called with maxsize/offset of 0, behave like
* pci_mapreg_map.
*/

reqsize = (reqsize != 0) ? reqsize : realmaxsize;
base += offset;

if (realmaxsize < (offset + reqsize))
return 1;

if (bus_space_map(tag, base, reqsize, busflags, &handle))
return 1;

if (pci_mapreg_map_enable_decode) {
s = splhigh();
csr = pci_conf_read(pa->pa_pc, pa->pa_tag, PCI_COMMAND_STATUS_REG);
csr |= (PCI_MAPREG_TYPE(type) == PCI_MAPREG_TYPE_IO) ?
PCI_COMMAND_IO_ENABLE : PCI_COMMAND_MEM_ENABLE;
pci_conf_write(pa->pa_pc, pa->pa_tag, PCI_COMMAND_STATUS_REG, csr);
splx(s);
}

if (tagp != NULL)
*tagp = tag;
if (handlep != NULL)
*handlep = handle;
if (basep != NULL)
*basep = base;
if (sizep != NULL)
*sizep = reqsize;

return 0;
}

int
pci_find_rom(const struct pci_attach_args *pa, bus_space_tag_t bst,
bus_space_handle_t bsh, bus_size_t sz, int type,
bus_space_handle_t *romh, bus_size_t *romsz)
{
bus_size_t offset = 0, imagesz;
uint16_t ptr;
int done = 0;

/*
* no upper bound check; i cannot imagine a 4GB ROM, but
* it appears the spec would allow it!
*/
if (sz < 1024)
return 1;

while (offset < sz && !done){
struct pci_rom_header hdr;
struct pci_rom rom;

hdr.romh_magic = bus_space_read_2(bst, bsh,
offset + offsetof (struct pci_rom_header, romh_magic));
hdr.romh_data_ptr = bus_space_read_2(bst, bsh,
offset + offsetof (struct pci_rom_header, romh_data_ptr));

/* no warning: quite possibly ROM is simply not populated */
if (hdr.romh_magic != PCI_ROM_HEADER_MAGIC)
return 1;

ptr = offset + hdr.romh_data_ptr;

if (ptr > sz) {
printf("pci_find_rom: rom data ptr out of range\n");
return 1;
}

rom.rom_signature = bus_space_read_4(bst, bsh, ptr);
rom.rom_vendor = bus_space_read_2(bst, bsh, ptr +
offsetof(struct pci_rom, rom_vendor));
rom.rom_product = bus_space_read_2(bst, bsh, ptr +
offsetof(struct pci_rom, rom_product));
rom.rom_class = bus_space_read_1(bst, bsh,
ptr + offsetof (struct pci_rom, rom_class));
rom.rom_subclass = bus_space_read_1(bst, bsh,
ptr + offsetof (struct pci_rom, rom_subclass));
rom.rom_interface = bus_space_read_1(bst, bsh,
ptr + offsetof (struct pci_rom, rom_interface));
rom.rom_len = bus_space_read_2(bst, bsh,
ptr + offsetof (struct pci_rom, rom_len));
rom.rom_code_type = bus_space_read_1(bst, bsh,
ptr + offsetof (struct pci_rom, rom_code_type));
rom.rom_indicator = bus_space_read_1(bst, bsh,
ptr + offsetof (struct pci_rom, rom_indicator));

if (rom.rom_signature != PCI_ROM_SIGNATURE) {
printf("pci_find_rom: bad rom data signature\n");
return 1;
}

imagesz = rom.rom_len * 512;

if ((rom.rom_vendor == PCI_VENDOR(pa->pa_id)) &&
(rom.rom_product == PCI_PRODUCT(pa->pa_id)) &&
(rom.rom_class == PCI_CLASS(pa->pa_class)) &&
(rom.rom_subclass == PCI_SUBCLASS(pa->pa_class)) &&
(rom.rom_interface == PCI_INTERFACE(pa->pa_class)) &&
(rom.rom_code_type == type)) {
*romsz = imagesz;
bus_space_subregion(bst, bsh, offset, imagesz, romh);
return 0;
}

/* last image check */
if (rom.rom_indicator & PCI_ROM_INDICATOR_LAST)
return 1;

/* offset by size */
offset += imagesz;
}
return 1;
}