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#include <linux/vt.h>
43
44#include <asm/sibyte/bcm1480_regs.h>
45#include <asm/sibyte/bcm1480_scd.h>
46#include <asm/sibyte/board.h>
47#include <asm/io.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 PCI_DEVICE_MODE 2
60
61static int bcm1480_bus_status;
62
63#define PCI_BRIDGE_DEVICE  0
64
65/*
66 * Read/write 32-bit values in config space.
67 */
68static inline u32 READCFG32(u32 addr)
69{
70	return *(u32 *)(cfg_space + (addr&~3));
71}
72
73static inline void WRITECFG32(u32 addr, u32 data)
74{
75	*(u32 *)(cfg_space + (addr & ~3)) = data;
76}
77
78int pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
79{
80	if (pin == 0)
81		return -1;
82
83	return K_BCM1480_INT_PCI_INTA - 1 + pin;
84}
85
86/* Do platform specific device initialization at pci_enable_device() time */
87int pcibios_plat_dev_init(struct pci_dev *dev)
88{
89	return 0;
90}
91
92/*
93 * Some checks before doing config cycles:
94 * In PCI Device Mode, hide everything on bus 0 except the LDT host
95 * bridge.  Otherwise, access is controlled by bridge MasterEn bits.
96 */
97static int bcm1480_pci_can_access(struct pci_bus *bus, int devfn)
98{
99	u32 devno;
100
101	if (!(bcm1480_bus_status & (PCI_BUS_ENABLED | PCI_DEVICE_MODE)))
102		return 0;
103
104	if (bus->number == 0) {
105		devno = PCI_SLOT(devfn);
106		if (bcm1480_bus_status & PCI_DEVICE_MODE)
107			return 0;
108		else
109			return 1;
110	} else
111		return 1;
112}
113
114/*
115 * Read/write access functions for various sizes of values
116 * in config space.  Return all 1's for disallowed accesses
117 * for a kludgy but adequate simulation of master aborts.
118 */
119
120static int bcm1480_pcibios_read(struct pci_bus *bus, unsigned int devfn,
121				int where, int size, u32 * val)
122{
123	u32 data = 0;
124
125	if ((size == 2) && (where & 1))
126		return PCIBIOS_BAD_REGISTER_NUMBER;
127	else if ((size == 4) && (where & 3))
128		return PCIBIOS_BAD_REGISTER_NUMBER;
129
130	if (bcm1480_pci_can_access(bus, devfn))
131		data = READCFG32(CFGADDR(bus, devfn, where));
132	else
133		data = 0xFFFFFFFF;
134
135	if (size == 1)
136		*val = (data >> ((where & 3) << 3)) & 0xff;
137	else if (size == 2)
138		*val = (data >> ((where & 3) << 3)) & 0xffff;
139	else
140		*val = data;
141
142	return PCIBIOS_SUCCESSFUL;
143}
144
145static int bcm1480_pcibios_write(struct pci_bus *bus, unsigned int devfn,
146				int where, int size, u32 val)
147{
148	u32 cfgaddr = CFGADDR(bus, devfn, where);
149	u32 data = 0;
150
151	if ((size == 2) && (where & 1))
152		return PCIBIOS_BAD_REGISTER_NUMBER;
153	else if ((size == 4) && (where & 3))
154		return PCIBIOS_BAD_REGISTER_NUMBER;
155
156	if (!bcm1480_pci_can_access(bus, devfn))
157		return PCIBIOS_BAD_REGISTER_NUMBER;
158
159	data = READCFG32(cfgaddr);
160
161	if (size == 1)
162		data = (data & ~(0xff << ((where & 3) << 3))) |
163		    (val << ((where & 3) << 3));
164	else if (size == 2)
165		data = (data & ~(0xffff << ((where & 3) << 3))) |
166		    (val << ((where & 3) << 3));
167	else
168		data = val;
169
170	WRITECFG32(cfgaddr, data);
171
172	return PCIBIOS_SUCCESSFUL;
173}
174
175struct pci_ops bcm1480_pci_ops = {
176	.read	= bcm1480_pcibios_read,
177	.write	= bcm1480_pcibios_write,
178};
179
180static struct resource bcm1480_mem_resource = {
181	.name	= "BCM1480 PCI MEM",
182	.start	= A_BCM1480_PHYS_PCI_MEM_MATCH_BYTES,
183	.end	= A_BCM1480_PHYS_PCI_MEM_MATCH_BYTES + 0xfffffffUL,
184	.flags	= IORESOURCE_MEM,
185};
186
187static struct resource bcm1480_io_resource = {
188	.name	= "BCM1480 PCI I/O",
189	.start	= A_BCM1480_PHYS_PCI_IO_MATCH_BYTES,
190	.end	= A_BCM1480_PHYS_PCI_IO_MATCH_BYTES + 0x1ffffffUL,
191	.flags	= IORESOURCE_IO,
192};
193
194struct pci_controller bcm1480_controller = {
195	.pci_ops	= &bcm1480_pci_ops,
196	.mem_resource	= &bcm1480_mem_resource,
197	.io_resource	= &bcm1480_io_resource,
198	.io_offset	= A_BCM1480_PHYS_PCI_IO_MATCH_BYTES,
199};
200
201
202static int __init bcm1480_pcibios_init(void)
203{
204	uint32_t cmdreg;
205	uint64_t reg;
206
207	/* CFE will assign PCI resources */
208	pci_set_flags(PCI_PROBE_ONLY);
209
210	/* Avoid ISA compat ranges.  */
211	PCIBIOS_MIN_IO = 0x00008000UL;
212	PCIBIOS_MIN_MEM = 0x01000000UL;
213
214	/* Set I/O resource limits. - unlimited for now to accommodate HT */
215	ioport_resource.end = 0xffffffffUL;
216	iomem_resource.end = 0xffffffffUL;
217
218	cfg_space = ioremap(A_BCM1480_PHYS_PCI_CFG_MATCH_BITS, 16*1024*1024);
219
220	/*
221	 * See if the PCI bus has been configured by the firmware.
222	 */
223	reg = __raw_readq(IOADDR(A_SCD_SYSTEM_CFG));
224	if (!(reg & M_BCM1480_SYS_PCI_HOST)) {
225		bcm1480_bus_status |= PCI_DEVICE_MODE;
226	} else {
227		cmdreg = READCFG32(CFGOFFSET(0, PCI_DEVFN(PCI_BRIDGE_DEVICE, 0),
228					     PCI_COMMAND));
229		if (!(cmdreg & PCI_COMMAND_MASTER)) {
230			printk
231			    ("PCI: Skipping PCI probe.	Bus is not initialized.\n");
232			iounmap(cfg_space);
233			return 1; /* XXX */
234		}
235		bcm1480_bus_status |= PCI_BUS_ENABLED;
236	}
237
238	/* turn on ExpMemEn */
239	cmdreg = READCFG32(CFGOFFSET(0, PCI_DEVFN(PCI_BRIDGE_DEVICE, 0), 0x40));
240	WRITECFG32(CFGOFFSET(0, PCI_DEVFN(PCI_BRIDGE_DEVICE, 0), 0x40),
241			cmdreg | 0x10);
242	cmdreg = READCFG32(CFGOFFSET(0, PCI_DEVFN(PCI_BRIDGE_DEVICE, 0), 0x40));
243
244	/*
245	 * Establish mappings in KSEG2 (kernel virtual) to PCI I/O
246	 * space.  Use "match bytes" policy to make everything look
247	 * little-endian.  So, you need to also set
248	 * CONFIG_SWAP_IO_SPACE, but this is the combination that
249	 * works correctly with most of Linux's drivers.
250	 * XXX ehs: Should this happen in PCI Device mode?
251	 */
252
253	bcm1480_controller.io_map_base = (unsigned long)
254		ioremap(A_BCM1480_PHYS_PCI_IO_MATCH_BYTES, 65536);
255	bcm1480_controller.io_map_base -= bcm1480_controller.io_offset;
256	set_io_port_base(bcm1480_controller.io_map_base);
257
258	register_pci_controller(&bcm1480_controller);
259
260#ifdef CONFIG_VGA_CONSOLE
261	console_lock();
262	do_take_over_console(&vga_con, 0, MAX_NR_CONSOLES-1, 1);
263	console_unlock();
264#endif
265	return 0;
266}
267
268arch_initcall(bcm1480_pcibios_init);
269