summaryrefslogtreecommitdiffstats
path: root/arch/arm/mach-iop3xx/iop331-pci.c
blob: 44dd213b48a350fe90c47288ea8f27fda43ece76 (plain)
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
/*
 * arch/arm/mach-iop3xx/iop331-pci.c
 *
 * PCI support for the Intel IOP331 chipset
 *
 * Author: Dave Jiang (dave.jiang@intel.com)
 * Copyright (C) 2003, 2004 Intel Corp.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/init.h>
#include <linux/ioport.h>

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

#include <asm/arch/iop331.h>

#undef DEBUG
#undef DEBUG1

#ifdef DEBUG
#define  DBG(x...) printk(x)
#else
#define  DBG(x...) do { } while (0)
#endif

#ifdef DEBUG1
#define  DBG1(x...) printk(x)
#else
#define  DBG1(x...) do { } while (0)
#endif

/*
 * This routine builds either a type0 or type1 configuration command.  If the
 * bus is on the 80331 then a type0 made, else a type1 is created.
 */
static u32 iop331_cfg_address(struct pci_bus *bus, int devfn, int where)
{
	struct pci_sys_data *sys = bus->sysdata;
	u32 addr;

	if (sys->busnr == bus->number)
		addr = 1 << (PCI_SLOT(devfn) + 16) | (PCI_SLOT(devfn) << 11);
	else
		addr = bus->number << 16 | PCI_SLOT(devfn) << 11 | 1;

	addr |=	PCI_FUNC(devfn) << 8 | (where & ~3);

	return addr;
}

/*
 * This routine checks the status of the last configuration cycle.  If an error
 * was detected it returns a 1, else it returns a 0.  The errors being checked
 * are parity, master abort, target abort (master and target).  These types of
 * errors occure during a config cycle where there is no device, like during
 * the discovery stage.
 */
static int iop331_pci_status(void)
{
	unsigned int status;
	int ret = 0;

	/*
	 * Check the status registers.
	 */
	status = *IOP331_ATUSR;
	if (status & 0xf900)
	{
		DBG("\t\t\tPCI: P0 - status = 0x%08x\n", status);
		*IOP331_ATUSR = status & 0xf900;
		ret = 1;
	}
	status = *IOP331_ATUISR;
	if (status & 0x679f)
	{
		DBG("\t\t\tPCI: P1 - status = 0x%08x\n", status);
		*IOP331_ATUISR = status & 0x679f;
		ret = 1;
	}
	return ret;
}

/*
 * Simply write the address register and read the configuration
 * data.  Note that the 4 nop's ensure that we are able to handle
 * a delayed abort (in theory.)
 */
static inline u32 iop331_read(unsigned long addr)
{
	u32 val;

	__asm__ __volatile__(
		"str	%1, [%2]\n\t"
		"ldr	%0, [%3]\n\t"
		"nop\n\t"
		"nop\n\t"
		"nop\n\t"
		"nop\n\t"
		: "=r" (val)
		: "r" (addr), "r" (IOP331_OCCAR), "r" (IOP331_OCCDR));

	return val;
}

/*
 * The read routines must check the error status of the last configuration
 * cycle.  If there was an error, the routine returns all hex f's.
 */
static int
iop331_read_config(struct pci_bus *bus, unsigned int devfn, int where,
		int size, u32 *value)
{
	unsigned long addr = iop331_cfg_address(bus, devfn, where);
	u32 val = iop331_read(addr) >> ((where & 3) * 8);

	if( iop331_pci_status() )
		val = 0xffffffff;

	*value = val;

	return PCIBIOS_SUCCESSFUL;
}

static int
iop331_write_config(struct pci_bus *bus, unsigned int devfn, int where,
		int size, u32 value)
{
	unsigned long addr = iop331_cfg_address(bus, devfn, where);
	u32 val;

	if (size != 4) {
		val = iop331_read(addr);
		if (!iop331_pci_status() == 0)
			return PCIBIOS_SUCCESSFUL;

		where = (where & 3) * 8;

		if (size == 1)
			val &= ~(0xff << where);
		else
			val &= ~(0xffff << where);

		*IOP331_OCCDR = val | value << where;
	} else {
		asm volatile(
			"str	%1, [%2]\n\t"
			"str	%0, [%3]\n\t"
			"nop\n\t"
			"nop\n\t"
			"nop\n\t"
			"nop\n\t"
			:
			: "r" (value), "r" (addr),
			  "r" (IOP331_OCCAR), "r" (IOP331_OCCDR));
	}

	return PCIBIOS_SUCCESSFUL;
}

static struct pci_ops iop331_ops = {
	.read	= iop331_read_config,
	.write	= iop331_write_config,
};

/*
 * When a PCI device does not exist during config cycles, the XScale gets a
 * bus error instead of returning 0xffffffff. This handler simply returns.
 */
int
iop331_pci_abort(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
{
	DBG("PCI abort: address = 0x%08lx fsr = 0x%03x PC = 0x%08lx LR = 0x%08lx\n",
		addr, fsr, regs->ARM_pc, regs->ARM_lr);

	/*
	 * 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;
}

/*
 * Scan an IOP331 PCI bus.  sys->bus defines which bus we scan.
 */
struct pci_bus *iop331_scan_bus(int nr, struct pci_sys_data *sys)
{
	return pci_scan_bus(sys->busnr, &iop331_ops, sys);
}

void iop331_init(void)
{
	DBG1("PCI:  Intel 80331 PCI init code.\n");
	DBG1("\tATU: IOP331_ATUCMD=0x%04x\n", *IOP331_ATUCMD);
	DBG1("\tATU: IOP331_OMWTVR0=0x%04x, IOP331_OIOWTVR=0x%04x\n",
			*IOP331_OMWTVR0,
			*IOP331_OIOWTVR);
	DBG1("\tATU: IOP331_OMWTVR1=0x%04x\n", *IOP331_OMWTVR1);
	DBG1("\tATU: IOP331_ATUCR=0x%08x\n", *IOP331_ATUCR);
	DBG1("\tATU: IOP331_IABAR0=0x%08x IOP331_IALR0=0x%08x IOP331_IATVR0=%08x\n", *IOP331_IABAR0, *IOP331_IALR0, *IOP331_IATVR0);
	DBG1("\tATU: IOP31_IABAR1=0x%08x IOP331_IALR1=0x%08x\n", *IOP331_IABAR1, *IOP331_IALR1);
	DBG1("\tATU: IOP331_ERBAR=0x%08x IOP331_ERLR=0x%08x IOP331_ERTVR=%08x\n", *IOP331_ERBAR, *IOP331_ERLR, *IOP331_ERTVR);
	DBG1("\tATU: IOP331_IABAR2=0x%08x IOP331_IALR2=0x%08x IOP331_IATVR2=%08x\n", *IOP331_IABAR2, *IOP331_IALR2, *IOP331_IATVR2);
	DBG1("\tATU: IOP331_IABAR3=0x%08x IOP331_IALR3=0x%08x IOP331_IATVR3=%08x\n", *IOP331_IABAR3, *IOP331_IALR3, *IOP331_IATVR3);

	hook_fault_code(16+6, iop331_pci_abort, SIGBUS, "imprecise external abort");
}