OpenCloudOS-Kernel/arch/x86/pci/early.c

104 lines
2.3 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/kernel.h>
#include <linux/pci.h>
#include <asm/pci-direct.h>
#include <asm/io.h>
#include <asm/pci_x86.h>
/* Direct PCI access. This is used for PCI accesses in early boot before
the PCI subsystem works. */
u32 read_pci_config(u8 bus, u8 slot, u8 func, u8 offset)
{
u32 v;
outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
v = inl(0xcfc);
return v;
}
u8 read_pci_config_byte(u8 bus, u8 slot, u8 func, u8 offset)
{
u8 v;
outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
v = inb(0xcfc + (offset&3));
return v;
}
u16 read_pci_config_16(u8 bus, u8 slot, u8 func, u8 offset)
{
u16 v;
outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
v = inw(0xcfc + (offset&2));
return v;
}
void write_pci_config(u8 bus, u8 slot, u8 func, u8 offset,
u32 val)
{
outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
outl(val, 0xcfc);
}
void write_pci_config_byte(u8 bus, u8 slot, u8 func, u8 offset, u8 val)
{
outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
outb(val, 0xcfc + (offset&3));
}
void write_pci_config_16(u8 bus, u8 slot, u8 func, u8 offset, u16 val)
{
outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
outw(val, 0xcfc + (offset&2));
}
int early_pci_allowed(void)
{
return (pci_probe & (PCI_PROBE_CONF1|PCI_PROBE_NOEARLY)) ==
PCI_PROBE_CONF1;
}
void early_dump_pci_device(u8 bus, u8 slot, u8 func)
{
u32 value[256 / 4];
int i;
pr_info("pci 0000:%02x:%02x.%d config space:\n", bus, slot, func);
for (i = 0; i < 256; i += 4)
value[i / 4] = read_pci_config(bus, slot, func, i);
print_hex_dump(KERN_INFO, "", DUMP_PREFIX_OFFSET, 16, 1, value, 256, false);
}
void early_dump_pci_devices(void)
{
unsigned bus, slot, func;
if (!early_pci_allowed())
return;
for (bus = 0; bus < 256; bus++) {
for (slot = 0; slot < 32; slot++) {
for (func = 0; func < 8; func++) {
u32 class;
u8 type;
class = read_pci_config(bus, slot, func,
PCI_CLASS_REVISION);
if (class == 0xffffffff)
continue;
early_dump_pci_device(bus, slot, func);
if (func == 0) {
type = read_pci_config_byte(bus, slot,
func,
PCI_HEADER_TYPE);
if (!(type & 0x80))
break;
}
}
}
}
}