summaryrefslogtreecommitdiff
path: root/arch/powerpc/kernel/rtas_pci.c
blob: fccf96e897f6a7b6f092f38b20c4d18142f650e7 (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
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2001 Dave Engebretsen, IBM Corporation
 * Copyright (C) 2003 Anton Blanchard <anton@au.ibm.com>, IBM
 *
 * RTAS specific routines for PCI.
 *
 * Based on code from pci.c, chrp_pci.c and pSeries_pci.c
 */

#include <linux/kernel.h>
#include <linux/threads.h>
#include <linux/pci.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/pgtable.h>
#include <linux/of_address.h>
#include <linux/of_fdt.h>

#include <asm/io.h>
#include <asm/irq.h>
#include <asm/machdep.h>
#include <asm/pci-bridge.h>
#include <asm/iommu.h>
#include <asm/rtas.h>
#include <asm/mpic.h>
#include <asm/ppc-pci.h>
#include <asm/eeh.h>

/* RTAS tokens */
static int read_pci_config;
static int write_pci_config;
static int ibm_read_pci_config;
static int ibm_write_pci_config;

static inline int config_access_valid(struct pci_dn *dn, int where)
{
	if (where < 256)
		return 1;
	if (where < 4096 && dn->pci_ext_config_space)
		return 1;

	return 0;
}

int rtas_pci_dn_read_config(struct pci_dn *pdn, int where, int size, u32 *val)
{
	int returnval = -1;
	unsigned long buid, addr;
	int ret;

	if (!pdn)
		return PCIBIOS_DEVICE_NOT_FOUND;
	if (!config_access_valid(pdn, where))
		return PCIBIOS_BAD_REGISTER_NUMBER;
#ifdef CONFIG_EEH
	if (pdn->edev && pdn->edev->pe &&
	    (pdn->edev->pe->state & EEH_PE_CFG_BLOCKED))
		return PCIBIOS_SET_FAILED;
#endif

	addr = rtas_config_addr(pdn->busno, pdn->devfn, where);
	buid = pdn->phb->buid;
	if (buid) {
		ret = rtas_call(ibm_read_pci_config, 4, 2, &returnval,
				addr, BUID_HI(buid), BUID_LO(buid), size);
	} else {
		ret = rtas_call(read_pci_config, 2, 2, &returnval, addr, size);
	}
	*val = returnval;

	if (ret)
		return PCIBIOS_DEVICE_NOT_FOUND;

	return PCIBIOS_SUCCESSFUL;
}

static int rtas_pci_read_config(struct pci_bus *bus,
				unsigned int devfn,
				int where, int size, u32 *val)
{
	struct pci_dn *pdn;
	int ret;

	*val = 0xFFFFFFFF;

	pdn = pci_get_pdn_by_devfn(bus, devfn);

	/* Validity of pdn is checked in here */
	ret = rtas_pci_dn_read_config(pdn, where, size, val);
	if (*val == EEH_IO_ERROR_VALUE(size) &&
	    eeh_dev_check_failure(pdn_to_eeh_dev(pdn)))
		return PCIBIOS_DEVICE_NOT_FOUND;

	return ret;
}

int rtas_pci_dn_write_config(struct pci_dn *pdn, int where, int size, u32 val)
{
	unsigned long buid, addr;
	int ret;

	if (!pdn)
		return PCIBIOS_DEVICE_NOT_FOUND;
	if (!config_access_valid(pdn, where))
		return PCIBIOS_BAD_REGISTER_NUMBER;
#ifdef CONFIG_EEH
	if (pdn->edev && pdn->edev->pe &&
	    (pdn->edev->pe->state & EEH_PE_CFG_BLOCKED))
		return PCIBIOS_SET_FAILED;
#endif

	addr = rtas_config_addr(pdn->busno, pdn->devfn, where);
	buid = pdn->phb->buid;
	if (buid) {
		ret = rtas_call(ibm_write_pci_config, 5, 1, NULL, addr,
			BUID_HI(buid), BUID_LO(buid), size, (ulong) val);
	} else {
		ret = rtas_call(write_pci_config, 3, 1, NULL, addr, size, (ulong)val);
	}

	if (ret)
		return PCIBIOS_DEVICE_NOT_FOUND;

	return PCIBIOS_SUCCESSFUL;
}

static int rtas_pci_write_config(struct pci_bus *bus,
				 unsigned int devfn,
				 int where, int size, u32 val)
{
	struct pci_dn *pdn;

	pdn = pci_get_pdn_by_devfn(bus, devfn);

	/* Validity of pdn is checked in here. */
	return rtas_pci_dn_write_config(pdn, where, size, val);
}

static struct pci_ops rtas_pci_ops = {
	.read = rtas_pci_read_config,
	.write = rtas_pci_write_config,
};

static int is_python(struct device_node *dev)
{
	const char *model = of_get_property(dev, "model", NULL);

	if (model && strstr(model, "Python"))
		return 1;

	return 0;
}

static void python_countermeasures(struct device_node *dev)
{
	struct resource registers;
	void __iomem *chip_regs;
	volatile u32 val;

	if (of_address_to_resource(dev, 0, &registers)) {
		printk(KERN_ERR "Can't get address for Python workarounds !\n");
		return;
	}

	/* Python's register file is 1 MB in size. */
	chip_regs = ioremap(registers.start & ~(0xfffffUL), 0x100000);

	/*
	 * Firmware doesn't always clear this bit which is critical
	 * for good performance - Anton
	 */

#define PRG_CL_RESET_VALID 0x00010000

	val = in_be32(chip_regs + 0xf6030);
	if (val & PRG_CL_RESET_VALID) {
		printk(KERN_INFO "Python workaround: ");
		val &= ~PRG_CL_RESET_VALID;
		out_be32(chip_regs + 0xf6030, val);
		/*
		 * We must read it back for changes to
		 * take effect
		 */
		val = in_be32(chip_regs + 0xf6030);
		printk("reg0: %x\n", val);
	}

	iounmap(chip_regs);
}

void __init init_pci_config_tokens(void)
{
	read_pci_config = rtas_function_token(RTAS_FN_READ_PCI_CONFIG);
	write_pci_config = rtas_function_token(RTAS_FN_WRITE_PCI_CONFIG);
	ibm_read_pci_config = rtas_function_token(RTAS_FN_IBM_READ_PCI_CONFIG);
	ibm_write_pci_config = rtas_function_token(RTAS_FN_IBM_WRITE_PCI_CONFIG);
}

unsigned long get_phb_buid(struct device_node *phb)
{
	struct resource r;

	if (ibm_read_pci_config == -1)
		return 0;
	if (of_address_to_resource(phb, 0, &r))
		return 0;
	return r.start;
}

static int phb_set_bus_ranges(struct device_node *dev,
			      struct pci_controller *phb)
{
	const __be32 *bus_range;
	unsigned int len;

	bus_range = of_get_property(dev, "bus-range", &len);
	if (bus_range == NULL || len < 2 * sizeof(int)) {
		return 1;
 	}

	phb->first_busno = be32_to_cpu(bus_range[0]);
	phb->last_busno  = be32_to_cpu(bus_range[1]);

	return 0;
}

int rtas_setup_phb(struct pci_controller *phb)
{
	struct device_node *dev = phb->dn;

	if (is_python(dev))
		python_countermeasures(dev);

	if (phb_set_bus_ranges(dev, phb))
		return 1;

	phb->ops = &rtas_pci_ops;
	phb->buid = get_phb_buid(dev);

	return 0;
}