summaryrefslogtreecommitdiff
path: root/arch/arm/mach-cns3xxx/pcie.c
blob: f6bf9f623d70b68bb7732029f436391de1253627 (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
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
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
/*
 * PCI-E support for CNS3xxx
 *
 * Copyright 2008 Cavium Networks
 *		  Richard Liu <richard.liu@caviumnetworks.com>
 * Copyright 2010 MontaVista Software, LLC.
 *		  Anton Vorontsov <avorontsov@mvista.com>
 *
 * This file 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/init.h>
#include <linux/kernel.h>
#include <linux/bug.h>
#include <linux/pci.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/ptrace.h>
#include <asm/mach/map.h>
#include "cns3xxx.h"
#include "core.h"

struct cns3xxx_pcie {
	void __iomem *host_regs; /* PCI config registers for host bridge */
	void __iomem *cfg0_regs; /* PCI Type 0 config registers */
	void __iomem *cfg1_regs; /* PCI Type 1 config registers */
	unsigned int irqs[2];
	struct resource res_io;
	struct resource res_mem;
	int port;
	bool linked;
};

static struct cns3xxx_pcie *sysdata_to_cnspci(void *sysdata)
{
	struct pci_sys_data *root = sysdata;

	return root->private_data;
}

static struct cns3xxx_pcie *pdev_to_cnspci(const struct pci_dev *dev)
{
	return sysdata_to_cnspci(dev->sysdata);
}

static struct cns3xxx_pcie *pbus_to_cnspci(struct pci_bus *bus)
{
	return sysdata_to_cnspci(bus->sysdata);
}

static void __iomem *cns3xxx_pci_cfg_base(struct pci_bus *bus,
				  unsigned int devfn, int where)
{
	struct cns3xxx_pcie *cnspci = pbus_to_cnspci(bus);
	int busno = bus->number;
	int slot = PCI_SLOT(devfn);
	void __iomem *base;

	/* If there is no link, just show the CNS PCI bridge. */
	if (!cnspci->linked && busno > 0)
		return NULL;

	/*
	 * The CNS PCI bridge doesn't fit into the PCI hierarchy, though
	 * we still want to access it. For this to work, we must place
	 * the first device on the same bus as the CNS PCI bridge.
	 */
	if (busno == 0) { /* internal PCIe bus, host bridge device */
		if (devfn == 0) /* device# and function# are ignored by hw */
			base = cnspci->host_regs;
		else
			return NULL; /* no such device */

	} else if (busno == 1) { /* directly connected PCIe device */
		if (slot == 0) /* device# is ignored by hw */
			base = cnspci->cfg0_regs;
		else
			return NULL; /* no such device */
	} else /* remote PCI bus */
		base = cnspci->cfg1_regs + ((busno & 0xf) << 20);

	return base + (where & 0xffc) + (devfn << 12);
}

static int cns3xxx_pci_read_config(struct pci_bus *bus, unsigned int devfn,
				   int where, int size, u32 *val)
{
	u32 v;
	void __iomem *base;
	u32 mask = (0x1ull << (size * 8)) - 1;
	int shift = (where % 4) * 8;

	base = cns3xxx_pci_cfg_base(bus, devfn, where);
	if (!base) {
		*val = 0xffffffff;
		return PCIBIOS_SUCCESSFUL;
	}

	v = __raw_readl(base);

	if (bus->number == 0 && devfn == 0 &&
			(where & 0xffc) == PCI_CLASS_REVISION) {
		/*
		 * RC's class is 0xb, but Linux PCI driver needs 0x604
		 * for a PCIe bridge. So we must fixup the class code
		 * to 0x604 here.
		 */
		v &= 0xff;
		v |= 0x604 << 16;
	}

	*val = (v >> shift) & mask;

	return PCIBIOS_SUCCESSFUL;
}

static int cns3xxx_pci_write_config(struct pci_bus *bus, unsigned int devfn,
				    int where, int size, u32 val)
{
	u32 v;
	void __iomem *base;
	u32 mask = (0x1ull << (size * 8)) - 1;
	int shift = (where % 4) * 8;

	base = cns3xxx_pci_cfg_base(bus, devfn, where);
	if (!base)
		return PCIBIOS_SUCCESSFUL;

	v = __raw_readl(base);

	v &= ~(mask << shift);
	v |= (val & mask) << shift;

	__raw_writel(v, base);

	return PCIBIOS_SUCCESSFUL;
}

static int cns3xxx_pci_setup(int nr, struct pci_sys_data *sys)
{
	struct cns3xxx_pcie *cnspci = sysdata_to_cnspci(sys);
	struct resource *res_io = &cnspci->res_io;
	struct resource *res_mem = &cnspci->res_mem;

	BUG_ON(request_resource(&iomem_resource, res_io) ||
	       request_resource(&iomem_resource, res_mem));

	pci_add_resource_offset(&sys->resources, res_io, sys->io_offset);
	pci_add_resource_offset(&sys->resources, res_mem, sys->mem_offset);

	return 1;
}

static struct pci_ops cns3xxx_pcie_ops = {
	.read = cns3xxx_pci_read_config,
	.write = cns3xxx_pci_write_config,
};

static int cns3xxx_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
{
	struct cns3xxx_pcie *cnspci = pdev_to_cnspci(dev);
	int irq = cnspci->irqs[!!dev->bus->number];

	pr_info("PCIe map irq: %04d:%02x:%02x.%02x slot %d, pin %d, irq: %d\n",
		pci_domain_nr(dev->bus), dev->bus->number, PCI_SLOT(dev->devfn),
		PCI_FUNC(dev->devfn), slot, pin, irq);

	return irq;
}

static struct cns3xxx_pcie cns3xxx_pcie[] = {
	[0] = {
		.host_regs = (void __iomem *)CNS3XXX_PCIE0_HOST_BASE_VIRT,
		.cfg0_regs = (void __iomem *)CNS3XXX_PCIE0_CFG0_BASE_VIRT,
		.cfg1_regs = (void __iomem *)CNS3XXX_PCIE0_CFG1_BASE_VIRT,
		.res_io = {
			.name = "PCIe0 I/O space",
			.start = CNS3XXX_PCIE0_IO_BASE,
			.end = CNS3XXX_PCIE0_CFG0_BASE - 1, /* 16 MiB */
			.flags = IORESOURCE_IO,
		},
		.res_mem = {
			.name = "PCIe0 non-prefetchable",
			.start = CNS3XXX_PCIE0_MEM_BASE,
			.end = CNS3XXX_PCIE0_HOST_BASE - 1, /* 176 MiB */
			.flags = IORESOURCE_MEM,
		},
		.irqs = { IRQ_CNS3XXX_PCIE0_RC, IRQ_CNS3XXX_PCIE0_DEVICE, },
		.port = 0,
	},
	[1] = {
		.host_regs = (void __iomem *)CNS3XXX_PCIE1_HOST_BASE_VIRT,
		.cfg0_regs = (void __iomem *)CNS3XXX_PCIE1_CFG0_BASE_VIRT,
		.cfg1_regs = (void __iomem *)CNS3XXX_PCIE1_CFG1_BASE_VIRT,
		.res_io = {
			.name = "PCIe1 I/O space",
			.start = CNS3XXX_PCIE1_IO_BASE,
			.end = CNS3XXX_PCIE1_CFG0_BASE - 1, /* 16 MiB */
			.flags = IORESOURCE_IO,
		},
		.res_mem = {
			.name = "PCIe1 non-prefetchable",
			.start = CNS3XXX_PCIE1_MEM_BASE,
			.end = CNS3XXX_PCIE1_HOST_BASE - 1, /* 176 MiB */
			.flags = IORESOURCE_MEM,
		},
		.irqs = { IRQ_CNS3XXX_PCIE1_RC, IRQ_CNS3XXX_PCIE1_DEVICE, },
		.port = 1,
	},
};

static void __init cns3xxx_pcie_check_link(struct cns3xxx_pcie *cnspci)
{
	int port = cnspci->port;
	u32 reg;
	unsigned long time;

	reg = __raw_readl(MISC_PCIE_CTRL(port));
	/*
	 * Enable Application Request to 1, it will exit L1 automatically,
	 * but when chip back, it will use another clock, still can use 0x1.
	 */
	reg |= 0x3;
	__raw_writel(reg, MISC_PCIE_CTRL(port));

	pr_info("PCIe: Port[%d] Enable PCIe LTSSM\n", port);
	pr_info("PCIe: Port[%d] Check data link layer...", port);

	time = jiffies;
	while (1) {
		reg = __raw_readl(MISC_PCIE_PM_DEBUG(port));
		if (reg & 0x1) {
			pr_info("Link up.\n");
			cnspci->linked = 1;
			break;
		} else if (time_after(jiffies, time + 50)) {
			pr_info("Device not found.\n");
			break;
		}
	}
}

static void __init cns3xxx_pcie_hw_init(struct cns3xxx_pcie *cnspci)
{
	int port = cnspci->port;
	struct pci_sys_data sd = {
		.private_data = cnspci,
	};
	struct pci_bus bus = {
		.number = 0,
		.ops = &cns3xxx_pcie_ops,
		.sysdata = &sd,
	};
	u16 mem_base  = cnspci->res_mem.start >> 16;
	u16 mem_limit = cnspci->res_mem.end   >> 16;
	u16 io_base   = cnspci->res_io.start  >> 16;
	u16 io_limit  = cnspci->res_io.end    >> 16;
	u32 devfn = 0;
	u8 tmp8;
	u16 pos;
	u16 dc;

	pci_bus_write_config_byte(&bus, devfn, PCI_PRIMARY_BUS, 0);
	pci_bus_write_config_byte(&bus, devfn, PCI_SECONDARY_BUS, 1);
	pci_bus_write_config_byte(&bus, devfn, PCI_SUBORDINATE_BUS, 1);

	pci_bus_read_config_byte(&bus, devfn, PCI_PRIMARY_BUS, &tmp8);
	pci_bus_read_config_byte(&bus, devfn, PCI_SECONDARY_BUS, &tmp8);
	pci_bus_read_config_byte(&bus, devfn, PCI_SUBORDINATE_BUS, &tmp8);

	pci_bus_write_config_word(&bus, devfn, PCI_MEMORY_BASE, mem_base);
	pci_bus_write_config_word(&bus, devfn, PCI_MEMORY_LIMIT, mem_limit);
	pci_bus_write_config_word(&bus, devfn, PCI_IO_BASE_UPPER16, io_base);
	pci_bus_write_config_word(&bus, devfn, PCI_IO_LIMIT_UPPER16, io_limit);

	if (!cnspci->linked)
		return;

	/* Set Device Max_Read_Request_Size to 128 byte */
	bus.number = 1; /* directly connected PCIe device */
	devfn = PCI_DEVFN(0, 0);
	pos = pci_bus_find_capability(&bus, devfn, PCI_CAP_ID_EXP);
	pci_bus_read_config_word(&bus, devfn, pos + PCI_EXP_DEVCTL, &dc);
	if (dc & PCI_EXP_DEVCTL_READRQ) {
		dc &= ~PCI_EXP_DEVCTL_READRQ;
		pci_bus_write_config_word(&bus, devfn, pos + PCI_EXP_DEVCTL, dc);
		pci_bus_read_config_word(&bus, devfn, pos + PCI_EXP_DEVCTL, &dc);
		if (dc & PCI_EXP_DEVCTL_READRQ)
			pr_warn("PCIe: Unable to set device Max_Read_Request_Size\n");
		else
			pr_info("PCIe: Max_Read_Request_Size set to 128 bytes\n");
	}
	/* Disable PCIe0 Interrupt Mask INTA to INTD */
	__raw_writel(~0x3FFF, MISC_PCIE_INT_MASK(port));
}

static int cns3xxx_pcie_abort_handler(unsigned long addr, unsigned int fsr,
				      struct pt_regs *regs)
{
	if (fsr & (1 << 10))
		regs->ARM_pc += 4;
	return 0;
}

void __init cns3xxx_pcie_init_late(void)
{
	int i;
	void *private_data;
	struct hw_pci hw_pci = {
	       .nr_controllers = 1,
	       .ops = &cns3xxx_pcie_ops,
	       .setup = cns3xxx_pci_setup,
	       .map_irq = cns3xxx_pcie_map_irq,
	       .private_data = &private_data,
	};

	pcibios_min_io = 0;
	pcibios_min_mem = 0;

	hook_fault_code(16 + 6, cns3xxx_pcie_abort_handler, SIGBUS, 0,
			"imprecise external abort");

	for (i = 0; i < ARRAY_SIZE(cns3xxx_pcie); i++) {
		cns3xxx_pwr_clk_en(0x1 << PM_CLK_GATE_REG_OFFSET_PCIE(i));
		cns3xxx_pwr_soft_rst(0x1 << PM_SOFT_RST_REG_OFFST_PCIE(i));
		cns3xxx_pcie_check_link(&cns3xxx_pcie[i]);
		cns3xxx_pcie_hw_init(&cns3xxx_pcie[i]);
		private_data = &cns3xxx_pcie[i];
		pci_common_init(&hw_pci);
	}

	pci_assign_unassigned_resources();
}