linux-sg2042/arch/mips/pci/ops-loongson3.c

117 lines
2.7 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/types.h>
#include <linux/pci.h>
#include <linux/kernel.h>
#include <asm/mips-boards/bonito64.h>
#include <loongson.h>
#define PCI_ACCESS_READ 0
#define PCI_ACCESS_WRITE 1
#define HT1LO_PCICFG_BASE 0x1a000000
#define HT1LO_PCICFG_BASE_TP1 0x1b000000
static int loongson3_pci_config_access(unsigned char access_type,
struct pci_bus *bus, unsigned int devfn,
int where, u32 *data)
{
unsigned char busnum = bus->number;
int function = PCI_FUNC(devfn);
int device = PCI_SLOT(devfn);
int reg = where & ~3;
void *addrp;
u64 addr;
if (where < PCI_CFG_SPACE_SIZE) { /* standard config */
addr = (busnum << 16) | (device << 11) | (function << 8) | reg;
if (busnum == 0) {
if (device > 31)
return PCIBIOS_DEVICE_NOT_FOUND;
addrp = (void *)TO_UNCAC(HT1LO_PCICFG_BASE | addr);
} else {
addrp = (void *)TO_UNCAC(HT1LO_PCICFG_BASE_TP1 | addr);
}
} else if (where < PCI_CFG_SPACE_EXP_SIZE) { /* extended config */
struct pci_dev *rootdev;
rootdev = pci_get_domain_bus_and_slot(0, 0, 0);
if (!rootdev)
return PCIBIOS_DEVICE_NOT_FOUND;
addr = pci_resource_start(rootdev, 3);
if (!addr)
return PCIBIOS_DEVICE_NOT_FOUND;
addr |= busnum << 20 | device << 15 | function << 12 | reg;
addrp = (void *)TO_UNCAC(addr);
} else {
return PCIBIOS_DEVICE_NOT_FOUND;
}
if (access_type == PCI_ACCESS_WRITE)
writel(*data, addrp);
else {
*data = readl(addrp);
if (*data == 0xffffffff) {
*data = -1;
return PCIBIOS_DEVICE_NOT_FOUND;
}
}
return PCIBIOS_SUCCESSFUL;
}
static int loongson3_pci_pcibios_read(struct pci_bus *bus, unsigned int devfn,
int where, int size, u32 *val)
{
u32 data = 0;
int ret = loongson3_pci_config_access(PCI_ACCESS_READ,
bus, devfn, where, &data);
if (ret != PCIBIOS_SUCCESSFUL)
return ret;
if (size == 1)
*val = (data >> ((where & 3) << 3)) & 0xff;
else if (size == 2)
*val = (data >> ((where & 3) << 3)) & 0xffff;
else
*val = data;
return PCIBIOS_SUCCESSFUL;
}
static int loongson3_pci_pcibios_write(struct pci_bus *bus, unsigned int devfn,
int where, int size, u32 val)
{
u32 data = 0;
int ret;
if (size == 4)
data = val;
else {
ret = loongson3_pci_config_access(PCI_ACCESS_READ,
bus, devfn, where, &data);
if (ret != PCIBIOS_SUCCESSFUL)
return ret;
if (size == 1)
data = (data & ~(0xff << ((where & 3) << 3))) |
(val << ((where & 3) << 3));
else if (size == 2)
data = (data & ~(0xffff << ((where & 3) << 3))) |
(val << ((where & 3) << 3));
}
ret = loongson3_pci_config_access(PCI_ACCESS_WRITE,
bus, devfn, where, &data);
return ret;
}
struct pci_ops loongson_pci_ops = {
.read = loongson3_pci_pcibios_read,
.write = loongson3_pci_pcibios_write
};