1 /***********************************************************************
2 * Copyright 2001 MontaVista Software Inc.
3 * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
5 * arch/mips/ddb5xxx/ddb5477/pci_ops.c
6 * Define the pci_ops for DB5477.
8 * Much of the code is derived from the original DDB5074 port by
9 * Geert Uytterhoeven <geert@sonycom.com>
11 * This program is free software; you can redistribute it and/or modify it
12 * under the terms of the GNU General Public License as published by the
13 * Free Software Foundation; either version 2 of the License, or (at your
14 * option) any later version.
15 ***********************************************************************
19 * DDB5477 has two PCI channels, external PCI and IOPIC (internal)
20 * Therefore we provide two sets of pci_ops.
22 #include <linux/pci.h>
23 #include <linux/kernel.h>
24 #include <linux/types.h>
26 #include <asm/addrspace.h>
27 #include <asm/debug.h>
29 #include <asm/ddb5xxx/ddb5xxx.h>
32 * config_swap structure records what set of pdar/pmr are used
33 * to access pci config space. It also provides a place hold the
34 * original values for future restoring.
36 struct pci_config_swap {
46 * On DDB5477, we have two sets of swap registers, for ext PCI and IOPCI.
48 struct pci_config_swap ext_pci_swap = {
54 struct pci_config_swap io_pci_swap = {
65 static inline u32 ddb_access_config_base(struct pci_config_swap *swap, u32 bus, /* 0 means top level bus */
69 u32 pciinit_offset = 0;
73 /* minimum pdar (window) size is 2MB */
74 db_assert(swap->config_size >= (2 << 20));
76 db_assert(slot_num < (1 << 5));
77 db_assert(bus < (1 << 8));
79 /* backup registers */
80 swap->pdar_backup = ddb_in32(swap->pdar);
81 swap->pmr_backup = ddb_in32(swap->pmr);
83 /* set the pdar (pci window) register */
84 ddb_set_pdar(swap->pdar, swap->config_base, swap->config_size, 32, /* 32 bit wide */
85 0, /* not on local memory bus */
86 0); /* not visible from PCI bus (N/A) */
89 * calcuate the absolute pci config addr;
90 * according to the spec, we start scanning from adr:11 (0x800)
94 pci_addr = 0x800 << slot_num;
97 pci_addr = (bus << 16) | (slot_num << 11);
101 * if pci_addr is less than pci config window size, we set
102 * pciinit_offset to 0 and adjust the virt_address.
103 * Otherwise we will try to adjust pciinit_offset.
105 if (pci_addr < swap->config_size) {
106 virt_addr = KSEG1ADDR(swap->config_base + pci_addr);
109 db_assert((pci_addr & (swap->config_size - 1)) == 0);
110 virt_addr = KSEG1ADDR(swap->config_base);
111 pciinit_offset = pci_addr;
114 /* set the pmr register */
115 option = DDB_PCI_ACCESS_32;
117 option |= DDB_PCI_CFGTYPE1;
118 ddb_set_pmr(swap->pmr, DDB_PCICMD_CFG, pciinit_offset, option);
123 static inline void ddb_close_config_base(struct pci_config_swap *swap)
125 ddb_out32(swap->pdar, swap->pdar_backup);
126 ddb_out32(swap->pmr, swap->pmr_backup);
129 static int read_config_dword(struct pci_config_swap *swap,
130 struct pci_bus *bus, u32 devfn, u32 where,
133 u32 bus_num, slot_num, func_num;
136 db_assert((where & 3) == 0);
137 db_assert(where < (1 << 8));
139 /* check if the bus is top-level */
140 if (bus->parent != NULL) {
141 bus_num = bus->number;
142 db_assert(bus_num != 0);
147 slot_num = PCI_SLOT(devfn);
148 func_num = PCI_FUNC(devfn);
149 base = ddb_access_config_base(swap, bus_num, slot_num);
150 *val = *(volatile u32 *) (base + (func_num << 8) + where);
151 ddb_close_config_base(swap);
152 return PCIBIOS_SUCCESSFUL;
155 static int read_config_word(struct pci_config_swap *swap,
156 struct pci_bus *bus, u32 devfn, u32 where,
162 db_assert((where & 1) == 0);
164 status = read_config_dword(swap, bus, devfn, where & ~3, &result);
167 *val = result & 0xffff;
171 static int read_config_byte(struct pci_config_swap *swap,
172 struct pci_bus *bus, u32 devfn, u32 where,
178 status = read_config_dword(swap, bus, devfn, where & ~3, &result);
183 *val = result & 0xff;
188 static int write_config_dword(struct pci_config_swap *swap,
189 struct pci_bus *bus, u32 devfn, u32 where,
192 u32 bus_num, slot_num, func_num;
195 db_assert((where & 3) == 0);
196 db_assert(where < (1 << 8));
198 /* check if the bus is top-level */
199 if (bus->parent != NULL) {
200 bus_num = bus->number;
201 db_assert(bus_num != 0);
206 slot_num = PCI_SLOT(devfn);
207 func_num = PCI_FUNC(devfn);
208 base = ddb_access_config_base(swap, bus_num, slot_num);
209 *(volatile u32 *) (base + (func_num << 8) + where) = val;
210 ddb_close_config_base(swap);
211 return PCIBIOS_SUCCESSFUL;
214 static int write_config_word(struct pci_config_swap *swap,
215 struct pci_bus *bus, u32 devfn, u32 where, u16 val)
217 int status, shift = 0;
220 db_assert((where & 1) == 0);
222 status = read_config_dword(swap, bus, devfn, where & ~3, &result);
223 if (status != PCIBIOS_SUCCESSFUL)
228 result &= ~(0xffff << shift);
229 result |= val << shift;
230 return write_config_dword(swap, bus, devfn, where & ~3, result);
233 static int write_config_byte(struct pci_config_swap *swap,
234 struct pci_bus *bus, u32 devfn, u32 where, u8 val)
236 int status, shift = 0;
239 status = read_config_dword(swap, bus, devfn, where & ~3, &result);
240 if (status != PCIBIOS_SUCCESSFUL)
247 result &= ~(0xff << shift);
248 result |= val << shift;
249 return write_config_dword(swap, bus, devfn, where & ~3, result);
252 #define MAKE_PCI_OPS(prefix, rw, pciswap, star) \
253 static int prefix##_##rw##_config(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 star val) \
256 return rw##_config_byte(pciswap, bus, devfn, where, (u8 star)val); \
257 else if (size == 2) \
258 return rw##_config_word(pciswap, bus, devfn, where, (u16 star)val); \
259 /* Size must be 4 */ \
260 return rw##_config_dword(pciswap, bus, devfn, where, val); \
263 MAKE_PCI_OPS(extpci, read, &ext_pci_swap, *)
264 MAKE_PCI_OPS(extpci, write, &ext_pci_swap,)
266 MAKE_PCI_OPS(iopci, read, &io_pci_swap, *)
267 MAKE_PCI_OPS(iopci, write, &io_pci_swap,)
269 struct pci_ops ddb5477_ext_pci_ops = {
270 .read = extpci_read_config,
271 .write = extpci_write_config
275 struct pci_ops ddb5477_io_pci_ops = {
276 .read = iopci_read_config,
277 .write = iopci_write_config