aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/pci/host/pci-layerscape.c
blob: 6697b1a4d4fa3c577fdd3c335587404dbac3f381 (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
/*
 * PCIe host controller driver for Freescale Layerscape SoCs
 *
 * Copyright (C) 2014 Freescale Semiconductor.
 *
  * Author: Minghuan Lian <Minghuan.Lian@freescale.com>
 *
 * 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/delay.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/of_pci.h>
#include <linux/of_platform.h>
#include <linux/of_irq.h>
#include <linux/of_address.h>
#include <linux/pci.h>
#include <linux/platform_device.h>
#include <linux/resource.h>
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>

#include "pcie-designware.h"

/* PEX1/2 Misc Ports Status Register */
#define SCFG_PEXMSCPORTSR(pex_idx)	(0x94 + (pex_idx) * 4)
#define LTSSM_STATE_SHIFT	20
#define LTSSM_STATE_MASK	0x3f
#define LTSSM_PCIE_L0		0x11 /* L0 state */

/* Symbol Timer Register and Filter Mask Register 1 */
#define PCIE_STRFMR1 0x71c

struct ls_pcie {
	struct list_head node;
	struct device *dev;
	struct pci_bus *bus;
	void __iomem *dbi;
	struct regmap *scfg;
	struct pcie_port pp;
	int index;
	int msi_irq;
};

#define to_ls_pcie(x)	container_of(x, struct ls_pcie, pp)

static int ls_pcie_link_up(struct pcie_port *pp)
{
	u32 state;
	struct ls_pcie *pcie = to_ls_pcie(pp);

	regmap_read(pcie->scfg, SCFG_PEXMSCPORTSR(pcie->index), &state);
	state = (state >> LTSSM_STATE_SHIFT) & LTSSM_STATE_MASK;

	if (state < LTSSM_PCIE_L0)
		return 0;

	return 1;
}

static void ls_pcie_host_init(struct pcie_port *pp)
{
	struct ls_pcie *pcie = to_ls_pcie(pp);
	int count = 0;
	u32 val;

	dw_pcie_setup_rc(pp);

	while (!ls_pcie_link_up(pp)) {
		usleep_range(100, 1000);
		count++;
		if (count >= 200) {
			dev_err(pp->dev, "phy link never came up\n");
			return;
		}
	}

	/*
	 * LS1021A Workaround for internal TKT228622
	 * to fix the INTx hang issue
	 */
	val = ioread32(pcie->dbi + PCIE_STRFMR1);
	val &= 0xffff;
	iowrite32(val, pcie->dbi + PCIE_STRFMR1);
}

static struct pcie_host_ops ls_pcie_host_ops = {
	.link_up = ls_pcie_link_up,
	.host_init = ls_pcie_host_init,
};

static int ls_add_pcie_port(struct ls_pcie *pcie)
{
	struct pcie_port *pp;
	int ret;

	pp = &pcie->pp;
	pp->dev = pcie->dev;
	pp->dbi_base = pcie->dbi;
	pp->root_bus_nr = -1;
	pp->ops = &ls_pcie_host_ops;

	ret = dw_pcie_host_init(pp);
	if (ret) {
		dev_err(pp->dev, "failed to initialize host\n");
		return ret;
	}

	return 0;
}

static int __init ls_pcie_probe(struct platform_device *pdev)
{
	struct ls_pcie *pcie;
	struct resource *dbi_base;
	u32 index[2];
	int ret;

	pcie = devm_kzalloc(&pdev->dev, sizeof(*pcie), GFP_KERNEL);
	if (!pcie)
		return -ENOMEM;

	pcie->dev = &pdev->dev;

	dbi_base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "regs");
	if (!dbi_base) {
		dev_err(&pdev->dev, "missing *regs* space\n");
		return -ENODEV;
	}

	pcie->dbi = devm_ioremap_resource(&pdev->dev, dbi_base);
	if (IS_ERR(pcie->dbi))
		return PTR_ERR(pcie->dbi);

	pcie->scfg = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
						     "fsl,pcie-scfg");
	if (IS_ERR(pcie->scfg)) {
		dev_err(&pdev->dev, "No syscfg phandle specified\n");
		return PTR_ERR(pcie->scfg);
	}

	ret = of_property_read_u32_array(pdev->dev.of_node,
					 "fsl,pcie-scfg", index, 2);
	if (ret)
		return ret;
	pcie->index = index[1];

	ret = ls_add_pcie_port(pcie);
	if (ret < 0)
		return ret;

	platform_set_drvdata(pdev, pcie);

	return 0;
}

static const struct of_device_id ls_pcie_of_match[] = {
	{ .compatible = "fsl,ls1021a-pcie" },
	{ },
};
MODULE_DEVICE_TABLE(of, ls_pcie_of_match);

static struct platform_driver ls_pcie_driver = {
	.driver = {
		.name = "layerscape-pcie",
		.owner = THIS_MODULE,
		.of_match_table = ls_pcie_of_match,
	},
};

module_platform_driver_probe(ls_pcie_driver, ls_pcie_probe);

MODULE_AUTHOR("Minghuan Lian <Minghuan.Lian@freescale.com>");
MODULE_DESCRIPTION("Freescale Layerscape PCIe host controller driver");
MODULE_LICENSE("GPL v2");