1 /*
2 * Copyright (C) 2001,2002,2005 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 * BCM1x80/1x55-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 * XXX: AT THIS TIME, ONLY the NATIVE PCI-X INTERFACE IS SUPPORTED.
34 */
35 #include <linux/types.h>
36 #include <linux/pci.h>
37 #include <linux/kernel.h>
38 #include <linux/init.h>
39 #include <linux/mm.h>
40 #include <linux/console.h>
41 #include <linux/tty.h>
42
43 #include <asm/sibyte/bcm1480_regs.h>
44 #include <asm/sibyte/bcm1480_scd.h>
45 #include <asm/sibyte/board.h>
46 #include <asm/io.h>
47
48 /*
49 * Macros for calculating offsets into config space given a device
50 * structure or dev/fun/reg
51 */
52 #define CFGOFFSET(bus, devfn, where) (((bus)<<16)+((devfn)<<8)+(where))
53 #define CFGADDR(bus, devfn, where) CFGOFFSET((bus)->number, (devfn), where)
54
55 static void *cfg_space;
56
57 #define PCI_BUS_ENABLED 1
58 #define PCI_DEVICE_MODE 2
59
60 static int bcm1480_bus_status;
61
62 #define PCI_BRIDGE_DEVICE 0
63
64 /*
65 * Read/write 32-bit values in config space.
66 */
READCFG32(u32 addr)67 static inline u32 READCFG32(u32 addr)
68 {
69 return *(u32 *)(cfg_space + (addr&~3));
70 }
71
WRITECFG32(u32 addr,u32 data)72 static inline void WRITECFG32(u32 addr, u32 data)
73 {
74 *(u32 *)(cfg_space + (addr & ~3)) = data;
75 }
76
pcibios_map_irq(const struct pci_dev * dev,u8 slot,u8 pin)77 int pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
78 {
79 if (pin == 0)
80 return -1;
81
82 return K_BCM1480_INT_PCI_INTA - 1 + pin;
83 }
84
85 /* Do platform specific device initialization at pci_enable_device() time */
pcibios_plat_dev_init(struct pci_dev * dev)86 int pcibios_plat_dev_init(struct pci_dev *dev)
87 {
88 return 0;
89 }
90
91 /*
92 * Some checks before doing config cycles:
93 * In PCI Device Mode, hide everything on bus 0 except the LDT host
94 * bridge. Otherwise, access is controlled by bridge MasterEn bits.
95 */
bcm1480_pci_can_access(struct pci_bus * bus,int devfn)96 static int bcm1480_pci_can_access(struct pci_bus *bus, int devfn)
97 {
98 u32 devno;
99
100 if (!(bcm1480_bus_status & (PCI_BUS_ENABLED | PCI_DEVICE_MODE)))
101 return 0;
102
103 if (bus->number == 0) {
104 devno = PCI_SLOT(devfn);
105 if (bcm1480_bus_status & PCI_DEVICE_MODE)
106 return 0;
107 else
108 return 1;
109 } else
110 return 1;
111 }
112
113 /*
114 * Read/write access functions for various sizes of values
115 * in config space. Return all 1's for disallowed accesses
116 * for a kludgy but adequate simulation of master aborts.
117 */
118
bcm1480_pcibios_read(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 * val)119 static int bcm1480_pcibios_read(struct pci_bus *bus, unsigned int devfn,
120 int where, int size, u32 * val)
121 {
122 u32 data = 0;
123
124 if ((size == 2) && (where & 1))
125 return PCIBIOS_BAD_REGISTER_NUMBER;
126 else if ((size == 4) && (where & 3))
127 return PCIBIOS_BAD_REGISTER_NUMBER;
128
129 if (bcm1480_pci_can_access(bus, devfn))
130 data = READCFG32(CFGADDR(bus, devfn, where));
131 else
132 data = 0xFFFFFFFF;
133
134 if (size == 1)
135 *val = (data >> ((where & 3) << 3)) & 0xff;
136 else if (size == 2)
137 *val = (data >> ((where & 3) << 3)) & 0xffff;
138 else
139 *val = data;
140
141 return PCIBIOS_SUCCESSFUL;
142 }
143
bcm1480_pcibios_write(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 val)144 static int bcm1480_pcibios_write(struct pci_bus *bus, unsigned int devfn,
145 int where, int size, u32 val)
146 {
147 u32 cfgaddr = CFGADDR(bus, devfn, where);
148 u32 data = 0;
149
150 if ((size == 2) && (where & 1))
151 return PCIBIOS_BAD_REGISTER_NUMBER;
152 else if ((size == 4) && (where & 3))
153 return PCIBIOS_BAD_REGISTER_NUMBER;
154
155 if (!bcm1480_pci_can_access(bus, devfn))
156 return PCIBIOS_BAD_REGISTER_NUMBER;
157
158 data = READCFG32(cfgaddr);
159
160 if (size == 1)
161 data = (data & ~(0xff << ((where & 3) << 3))) |
162 (val << ((where & 3) << 3));
163 else if (size == 2)
164 data = (data & ~(0xffff << ((where & 3) << 3))) |
165 (val << ((where & 3) << 3));
166 else
167 data = val;
168
169 WRITECFG32(cfgaddr, data);
170
171 return PCIBIOS_SUCCESSFUL;
172 }
173
174 struct pci_ops bcm1480_pci_ops = {
175 bcm1480_pcibios_read,
176 bcm1480_pcibios_write,
177 };
178
179 static struct resource bcm1480_mem_resource = {
180 .name = "BCM1480 PCI MEM",
181 .start = A_BCM1480_PHYS_PCI_MEM_MATCH_BYTES,
182 .end = A_BCM1480_PHYS_PCI_MEM_MATCH_BYTES + 0xfffffffUL,
183 .flags = IORESOURCE_MEM,
184 };
185
186 static struct resource bcm1480_io_resource = {
187 .name = "BCM1480 PCI I/O",
188 .start = A_BCM1480_PHYS_PCI_IO_MATCH_BYTES,
189 .end = A_BCM1480_PHYS_PCI_IO_MATCH_BYTES + 0x1ffffffUL,
190 .flags = IORESOURCE_IO,
191 };
192
193 struct pci_controller bcm1480_controller = {
194 .pci_ops = &bcm1480_pci_ops,
195 .mem_resource = &bcm1480_mem_resource,
196 .io_resource = &bcm1480_io_resource,
197 .io_offset = A_BCM1480_PHYS_PCI_IO_MATCH_BYTES,
198 };
199
200
bcm1480_pcibios_init(void)201 static int __init bcm1480_pcibios_init(void)
202 {
203 uint32_t cmdreg;
204 uint64_t reg;
205
206 /* CFE will assign PCI resources */
207 pci_set_flags(PCI_PROBE_ONLY);
208
209 /* Avoid ISA compat ranges. */
210 PCIBIOS_MIN_IO = 0x00008000UL;
211 PCIBIOS_MIN_MEM = 0x01000000UL;
212
213 /* Set I/O resource limits. - unlimited for now to accommodate HT */
214 ioport_resource.end = 0xffffffffUL;
215 iomem_resource.end = 0xffffffffUL;
216
217 cfg_space = ioremap(A_BCM1480_PHYS_PCI_CFG_MATCH_BITS, 16*1024*1024);
218
219 /*
220 * See if the PCI bus has been configured by the firmware.
221 */
222 reg = __raw_readq(IOADDR(A_SCD_SYSTEM_CFG));
223 if (!(reg & M_BCM1480_SYS_PCI_HOST)) {
224 bcm1480_bus_status |= PCI_DEVICE_MODE;
225 } else {
226 cmdreg = READCFG32(CFGOFFSET(0, PCI_DEVFN(PCI_BRIDGE_DEVICE, 0),
227 PCI_COMMAND));
228 if (!(cmdreg & PCI_COMMAND_MASTER)) {
229 printk
230 ("PCI: Skipping PCI probe. Bus is not initialized.\n");
231 iounmap(cfg_space);
232 return 1; /* XXX */
233 }
234 bcm1480_bus_status |= PCI_BUS_ENABLED;
235 }
236
237 /* turn on ExpMemEn */
238 cmdreg = READCFG32(CFGOFFSET(0, PCI_DEVFN(PCI_BRIDGE_DEVICE, 0), 0x40));
239 WRITECFG32(CFGOFFSET(0, PCI_DEVFN(PCI_BRIDGE_DEVICE, 0), 0x40),
240 cmdreg | 0x10);
241 cmdreg = READCFG32(CFGOFFSET(0, PCI_DEVFN(PCI_BRIDGE_DEVICE, 0), 0x40));
242
243 /*
244 * Establish mappings in KSEG2 (kernel virtual) to PCI I/O
245 * space. Use "match bytes" policy to make everything look
246 * little-endian. So, you need to also set
247 * CONFIG_SWAP_IO_SPACE, but this is the combination that
248 * works correctly with most of Linux's drivers.
249 * XXX ehs: Should this happen in PCI Device mode?
250 */
251
252 bcm1480_controller.io_map_base = (unsigned long)
253 ioremap(A_BCM1480_PHYS_PCI_IO_MATCH_BYTES, 65536);
254 bcm1480_controller.io_map_base -= bcm1480_controller.io_offset;
255 set_io_port_base(bcm1480_controller.io_map_base);
256
257 register_pci_controller(&bcm1480_controller);
258
259 #ifdef CONFIG_VGA_CONSOLE
260 take_over_console(&vga_con, 0, MAX_NR_CONSOLES-1, 1);
261 #endif
262 return 0;
263 }
264
265 arch_initcall(bcm1480_pcibios_init);
266