blob: 7cca3bde59b24d09c01d48dd816345c9e5fe89e7 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Copyright (C) 2001,2002,2003 Broadcom Corporation
3 * Copyright (C) 2004 by Ralf Baechle (ralf@linux-mips.org)
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License
7 * as published by the Free Software Foundation; either version 2
8 * of the License, or (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
18 */
19
20/*
21 * BCM1250-specific PCI support
22 *
23 * This module provides the glue between Linux's PCI subsystem
24 * and the hardware. We basically provide glue for accessing
25 * configuration space, and set up the translation for I/O
26 * space accesses.
27 *
28 * To access configuration space, we use ioremap. In the 32-bit
29 * kernel, this consumes either 4 or 8 page table pages, and 16MB of
30 * kernel mapped memory. Hopefully neither of these should be a huge
31 * problem.
32 */
33#include <linux/config.h>
34#include <linux/types.h>
35#include <linux/pci.h>
36#include <linux/kernel.h>
37#include <linux/init.h>
38#include <linux/mm.h>
39#include <linux/console.h>
40#include <linux/tty.h>
41
42#include <asm/io.h>
43
44#include <asm/sibyte/sb1250_defs.h>
45#include <asm/sibyte/sb1250_regs.h>
46#include <asm/sibyte/sb1250_scd.h>
47#include <asm/sibyte/board.h>
48
49/*
50 * Macros for calculating offsets into config space given a device
51 * structure or dev/fun/reg
52 */
53#define CFGOFFSET(bus,devfn,where) (((bus)<<16) + ((devfn)<<8) + (where))
54#define CFGADDR(bus,devfn,where) CFGOFFSET((bus)->number,(devfn),where)
55
56static void *cfg_space;
57
58#define PCI_BUS_ENABLED 1
59#define LDT_BUS_ENABLED 2
60#define PCI_DEVICE_MODE 4
61
62static int sb1250_bus_status = 0;
63
64#define PCI_BRIDGE_DEVICE 0
65#define LDT_BRIDGE_DEVICE 1
66
67#ifdef CONFIG_SIBYTE_HAS_LDT
68/*
69 * HT's level-sensitive interrupts require EOI, which is generated
70 * through a 4MB memory-mapped region
71 */
72unsigned long ldt_eoi_space;
73#endif
74
75/*
76 * Read/write 32-bit values in config space.
77 */
78static inline u32 READCFG32(u32 addr)
79{
80 return *(u32 *) (cfg_space + (addr & ~3));
81}
82
83static inline void WRITECFG32(u32 addr, u32 data)
84{
85 *(u32 *) (cfg_space + (addr & ~3)) = data;
86}
87
88int pcibios_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
89{
90 return dev->irq;
91}
92
93/* Do platform specific device initialization at pci_enable_device() time */
94int pcibios_plat_dev_init(struct pci_dev *dev)
95{
96 return 0;
97}
98
99/*
100 * Some checks before doing config cycles:
101 * In PCI Device Mode, hide everything on bus 0 except the LDT host
102 * bridge. Otherwise, access is controlled by bridge MasterEn bits.
103 */
104static int sb1250_pci_can_access(struct pci_bus *bus, int devfn)
105{
106 u32 devno;
107
108 if (!(sb1250_bus_status & (PCI_BUS_ENABLED | PCI_DEVICE_MODE)))
109 return 0;
110
111 if (bus->number == 0) {
112 devno = PCI_SLOT(devfn);
113 if (devno == LDT_BRIDGE_DEVICE)
114 return (sb1250_bus_status & LDT_BUS_ENABLED) != 0;
115 else if (sb1250_bus_status & PCI_DEVICE_MODE)
116 return 0;
117 else
118 return 1;
119 } else
120 return 1;
121}
122
123/*
124 * Read/write access functions for various sizes of values
125 * in config space. Return all 1's for disallowed accesses
126 * for a kludgy but adequate simulation of master aborts.
127 */
128
129static int sb1250_pcibios_read(struct pci_bus *bus, unsigned int devfn,
130 int where, int size, u32 * val)
131{
132 u32 data = 0;
133
134 if ((size == 2) && (where & 1))
135 return PCIBIOS_BAD_REGISTER_NUMBER;
136 else if ((size == 4) && (where & 3))
137 return PCIBIOS_BAD_REGISTER_NUMBER;
138
139 if (sb1250_pci_can_access(bus, devfn))
140 data = READCFG32(CFGADDR(bus, devfn, where));
141 else
142 data = 0xFFFFFFFF;
143
144 if (size == 1)
145 *val = (data >> ((where & 3) << 3)) & 0xff;
146 else if (size == 2)
147 *val = (data >> ((where & 3) << 3)) & 0xffff;
148 else
149 *val = data;
150
151 return PCIBIOS_SUCCESSFUL;
152}
153
154static int sb1250_pcibios_write(struct pci_bus *bus, unsigned int devfn,
155 int where, int size, u32 val)
156{
157 u32 cfgaddr = CFGADDR(bus, devfn, where);
158 u32 data = 0;
159
160 if ((size == 2) && (where & 1))
161 return PCIBIOS_BAD_REGISTER_NUMBER;
162 else if ((size == 4) && (where & 3))
163 return PCIBIOS_BAD_REGISTER_NUMBER;
164
165 if (!sb1250_pci_can_access(bus, devfn))
166 return PCIBIOS_BAD_REGISTER_NUMBER;
167
168 data = READCFG32(cfgaddr);
169
170 if (size == 1)
171 data = (data & ~(0xff << ((where & 3) << 3))) |
172 (val << ((where & 3) << 3));
173 else if (size == 2)
174 data = (data & ~(0xffff << ((where & 3) << 3))) |
175 (val << ((where & 3) << 3));
176 else
177 data = val;
178
179 WRITECFG32(cfgaddr, data);
180
181 return PCIBIOS_SUCCESSFUL;
182}
183
184struct pci_ops sb1250_pci_ops = {
185 .read = sb1250_pcibios_read,
186 .write = sb1250_pcibios_write,
187};
188
189static struct resource sb1250_mem_resource = {
190 .name = "SB1250 PCI MEM",
191 .start = 0x40000000UL,
192 .end = 0x5fffffffUL,
193 .flags = IORESOURCE_MEM,
194};
195
196static struct resource sb1250_io_resource = {
197 .name = "SB1250 PCI I/O",
198 .start = 0x00000000UL,
199 .end = 0x01ffffffUL,
200 .flags = IORESOURCE_IO,
201};
202
203struct pci_controller sb1250_controller = {
204 .pci_ops = &sb1250_pci_ops,
205 .mem_resource = &sb1250_mem_resource,
206 .io_resource = &sb1250_io_resource,
207};
208
209static int __init sb1250_pcibios_init(void)
210{
211 uint32_t cmdreg;
212 uint64_t reg;
213 extern int pci_probe_only;
214
215 /* CFE will assign PCI resources */
216 pci_probe_only = 1;
217
218 /* Avoid ISA compat ranges. */
219 PCIBIOS_MIN_IO = 0x00008000UL;
220 PCIBIOS_MIN_MEM = 0x01000000UL;
221
222 /* Set I/O resource limits. */
223 ioport_resource.end = 0x01ffffffUL; /* 32MB accessible by sb1250 */
224 iomem_resource.end = 0xffffffffUL; /* no HT support yet */
225
226 cfg_space =
227 ioremap(A_PHYS_LDTPCI_CFG_MATCH_BITS, 16 * 1024 * 1024);
228
229 /*
230 * See if the PCI bus has been configured by the firmware.
231 */
232 reg = *((volatile uint64_t *) IOADDR(A_SCD_SYSTEM_CFG));
233 if (!(reg & M_SYS_PCI_HOST)) {
234 sb1250_bus_status |= PCI_DEVICE_MODE;
235 } else {
236 cmdreg =
237 READCFG32(CFGOFFSET
238 (0, PCI_DEVFN(PCI_BRIDGE_DEVICE, 0),
239 PCI_COMMAND));
240 if (!(cmdreg & PCI_COMMAND_MASTER)) {
241 printk
242 ("PCI: Skipping PCI probe. Bus is not initialized.\n");
243 iounmap(cfg_space);
244 return 0;
245 }
246 sb1250_bus_status |= PCI_BUS_ENABLED;
247 }
248
249 /*
250 * Establish mappings in KSEG2 (kernel virtual) to PCI I/O
251 * space. Use "match bytes" policy to make everything look
252 * little-endian. So, you need to also set
253 * CONFIG_SWAP_IO_SPACE, but this is the combination that
254 * works correctly with most of Linux's drivers.
255 * XXX ehs: Should this happen in PCI Device mode?
256 */
257
258 set_io_port_base((unsigned long)
259 ioremap(A_PHYS_LDTPCI_IO_MATCH_BYTES, 65536));
260 isa_slot_offset = (unsigned long)
261 ioremap(A_PHYS_LDTPCI_IO_MATCH_BYTES_32, 1024 * 1024);
262
263#ifdef CONFIG_SIBYTE_HAS_LDT
264 /*
265 * Also check the LDT bridge's enable, just in case we didn't
266 * initialize that one.
267 */
268
269 cmdreg = READCFG32(CFGOFFSET(0, PCI_DEVFN(LDT_BRIDGE_DEVICE, 0),
270 PCI_COMMAND));
271 if (cmdreg & PCI_COMMAND_MASTER) {
272 sb1250_bus_status |= LDT_BUS_ENABLED;
273
274 /*
275 * Need bits 23:16 to convey vector number. Note that
276 * this consumes 4MB of kernel-mapped memory
277 * (Kseg2/Kseg3) for 32-bit kernel.
278 */
279 ldt_eoi_space = (unsigned long)
280 ioremap(A_PHYS_LDT_SPECIAL_MATCH_BYTES,
281 4 * 1024 * 1024);
282 }
283#endif
284
285 register_pci_controller(&sb1250_controller);
286
287#ifdef CONFIG_VGA_CONSOLE
288 take_over_console(&vga_con, 0, MAX_NR_CONSOLES - 1, 1);
289#endif
290 return 0;
291}
292arch_initcall(sb1250_pcibios_init);