aboutsummaryrefslogtreecommitdiffstats
path: root/arch/arm/mach-ixp23xx/pci.c
blob: db24c43449d7472896f2c9062f81ac872be20cb4 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
/*
 * arch/arm/mach-ixp23xx/pci.c
 *
 * PCI routines for IXP23XX based systems
 *
 * Copyright (c) 2005 MontaVista Software, Inc.
 *
 * based on original code:
 *
 * Author: Naeem Afzal <naeem.m.afzal@intel.com>
 * Copyright 2002-2005 Intel Corp.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.
 */

#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/mm.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/slab.h>
#include <linux/delay.h>

#include <asm/io.h>
#include <asm/irq.h>
#include <asm/sizes.h>
#include <asm/system.h>
#include <asm/mach/pci.h>
#include <asm/hardware.h>

extern int (*external_fault) (unsigned long, struct pt_regs *);

static volatile int pci_master_aborts = 0;

#ifdef DEBUG
#define DBG(x...)	printk(x)
#else
#define DBG(x...)
#endif

int clear_master_aborts(void);

static u32
*ixp23xx_pci_config_addr(unsigned int bus_nr, unsigned int devfn, int where)
{
	u32 *paddress;

	/*
	 * Must be dword aligned
	 */
	where &= ~3;

	/*
	 * For top bus, generate type 0, else type 1
	 */
	if (!bus_nr) {
		if (PCI_SLOT(devfn) >= 8)
			return 0;

		paddress = (u32 *) (IXP23XX_PCI_CFG0_VIRT
				    | (1 << (PCI_SLOT(devfn) + 16))
				    | (PCI_FUNC(devfn) << 8) | where);
	} else {
		paddress = (u32 *) (IXP23XX_PCI_CFG1_VIRT
				    | (bus_nr << 16)
				    | (PCI_SLOT(devfn) << 11)
				    | (PCI_FUNC(devfn) << 8) | where);
	}

	return paddress;
}

/*
 * Mask table, bits to mask for quantity of size 1, 2 or 4 bytes.
 * 0 and 3 are not valid indexes...
 */
static u32 bytemask[] = {
	/*0*/	0,
	/*1*/	0xff,
	/*2*/	0xffff,
	/*3*/	0,
	/*4*/	0xffffffff,
};

static int ixp23xx_pci_read_config(struct pci_bus *bus, unsigned int devfn,
				int where, int size, u32 *value)
{
	u32 n;
	u32 *addr;

	n = where % 4;

	DBG("In config_read(%d) %d from dev %d:%d:%d\n", size, where,
		bus->number, PCI_SLOT(devfn), PCI_FUNC(devfn));

	addr = ixp23xx_pci_config_addr(bus->number, devfn, where);
	if (!addr)
		return PCIBIOS_DEVICE_NOT_FOUND;

	pci_master_aborts = 0;
	*value = (*addr >> (8*n)) & bytemask[size];
	if (pci_master_aborts) {
			pci_master_aborts = 0;
			*value = 0xffffffff;
			return PCIBIOS_DEVICE_NOT_FOUND;
		}

	return PCIBIOS_SUCCESSFUL;
}

/*
 * We don't do error checking on the address for writes.
 * It's assumed that the user checked for the device existing first
 * by doing a read first.
 */
static int ixp23xx_pci_write_config(struct pci_bus *bus, unsigned int devfn,
					int where, int size, u32 value)
{
	u32 mask;
	u32 *addr;
	u32 temp;

	mask = ~(bytemask[size] << ((where % 0x4) * 8));
	addr = ixp23xx_pci_config_addr(bus->number, devfn, where);
	if (!addr)
		return PCIBIOS_DEVICE_NOT_FOUND;
	temp = (u32) (value) << ((where % 0x4) * 8);
	*addr = (*addr & mask) | temp;

	clear_master_aborts();

	return PCIBIOS_SUCCESSFUL;
}

struct pci_ops ixp23xx_pci_ops = {
	.read	= ixp23xx_pci_read_config,
	.write	= ixp23xx_pci_write_config,
};

struct pci_bus *ixp23xx_pci_scan_bus(int nr, struct pci_sys_data *sysdata)
{
	return pci_scan_bus(sysdata->busnr, &ixp23xx_pci_ops, sysdata);
}

int ixp23xx_pci_abort_handler(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
{
	volatile unsigned long temp;
	unsigned long flags;

	pci_master_aborts = 1;

	local_irq_save(flags);
	temp = *IXP23XX_PCI_CONTROL;

	/*
	 * master abort and cmd tgt err
	 */
	if (temp & ((1 << 8) | (1 << 5)))
		*IXP23XX_PCI_CONTROL = temp;

	temp = *IXP23XX_PCI_CMDSTAT;

	if (temp & (1 << 29))
		*IXP23XX_PCI_CMDSTAT = temp;
	local_irq_restore(flags);

	/*
	 * If it was an imprecise abort, then we need to correct the
	 * return address to be _after_ the instruction.
	 */
	if (fsr & (1 << 10))
		regs->ARM_pc += 4;

	return 0;
}

int clear_master_aborts(void)
{
	volatile u32 temp;

	temp = *IXP23XX_PCI_CONTROL;

	/*
	 * master abort and cmd tgt err
	 */
	if (temp & ((1 << 8) | (1 << 5)))
		*IXP23XX_PCI_CONTROL = temp;

	temp = *IXP23XX_PCI_CMDSTAT;

	if (temp & (1 << 29))
		*IXP23XX_PCI_CMDSTAT = temp;

	return 0;
}

static void __init ixp23xx_pci_common_init(void)
{
#ifdef __ARMEB__
	*IXP23XX_PCI_CONTROL |= 0x20000;	/* set I/O swapping */
#endif
	/*
	 * ADDR_31 needs to be clear for PCI memory access to CPP memory
	 */
	*IXP23XX_CPP2XSI_CURR_XFER_REG3 &= ~IXP23XX_CPP2XSI_ADDR_31;
	*IXP23XX_CPP2XSI_CURR_XFER_REG3 |= IXP23XX_CPP2XSI_PSH_OFF;

	/*
	 * Select correct memory for PCI inbound transactions
	 */
	if (ixp23xx_cpp_boot()) {
		*IXP23XX_PCI_CPP_ADDR_BITS &= ~(1 << 1);
	} else {
		*IXP23XX_PCI_CPP_ADDR_BITS |= (1 << 1);

		/*
		 * Enable coherency on A2 silicon.
		 */
		if (arch_is_coherent())
			*IXP23XX_CPP2XSI_CURR_XFER_REG3 &= ~IXP23XX_CPP2XSI_COH_OFF;
	}
}

void __init ixp23xx_pci_preinit(void)
{
	ixp23xx_pci_common_init();

	hook_fault_code(16+6, ixp23xx_pci_abort_handler, SIGBUS,
			"PCI config cycle to non-existent device");

	*IXP23XX_PCI_ADDR_EXT = 0x0000e000;
}

/*
 * Prevent PCI layer from seeing the inbound host-bridge resources
 */
static void __devinit pci_fixup_ixp23xx(struct pci_dev *dev)
{
	int i;

	dev->class &= 0xff;
	dev->class |= PCI_CLASS_BRIDGE_HOST << 8;
	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
		dev->resource[i].start = 0;
		dev->resource[i].end   = 0;
		dev->resource[i].flags = 0;
	}
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x9002, pci_fixup_ixp23xx);

/*
 * IXP2300 systems often have large resource requirements, so we just
 * use our own resource space.
 */
static struct resource ixp23xx_pci_mem_space = {
	.start	= IXP23XX_PCI_MEM_START,
	.end	= IXP23XX_PCI_MEM_START + IXP23XX_PCI_MEM_SIZE - 1,
	.flags	= IORESOURCE_MEM,
	.name	= "PCI Mem Space"
};

static struct resource ixp23xx_pci_io_space = {
	.start	= 0x00000100,
	.end	= 0x01ffffff,
	.flags	= IORESOURCE_IO,
	.name	= "PCI I/O Space"
};

int ixp23xx_pci_setup(int nr, struct pci_sys_data *sys)
{
	if (nr >= 1)
		return 0;

	sys->resource[0] = &ixp23xx_pci_io_space;
	sys->resource[1] = &ixp23xx_pci_mem_space;
	sys->resource[2] = NULL;

	return 1;
}

void __init ixp23xx_pci_slave_init(void)
{
	ixp23xx_pci_common_init();
}