xref: /openbmc/linux/drivers/net/can/m_can/m_can_pci.c (revision caa80275)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * PCI Specific M_CAN Glue
4  *
5  * Copyright (C) 2018-2020 Intel Corporation
6  * Author: Felipe Balbi (Intel)
7  * Author: Jarkko Nikula <jarkko.nikula@linux.intel.com>
8  * Author: Raymond Tan <raymond.tan@intel.com>
9  */
10 
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/netdevice.h>
14 #include <linux/pci.h>
15 #include <linux/pm_runtime.h>
16 
17 #include "m_can.h"
18 
19 #define M_CAN_PCI_MMIO_BAR		0
20 
21 #define M_CAN_CLOCK_FREQ_EHL		100000000
22 #define CTL_CSR_INT_CTL_OFFSET		0x508
23 
24 struct m_can_pci_priv {
25 	struct m_can_classdev cdev;
26 
27 	void __iomem *base;
28 };
29 
30 static inline struct m_can_pci_priv *cdev_to_priv(struct m_can_classdev *cdev)
31 {
32 	return container_of(cdev, struct m_can_pci_priv, cdev);
33 }
34 
35 static u32 iomap_read_reg(struct m_can_classdev *cdev, int reg)
36 {
37 	struct m_can_pci_priv *priv = cdev_to_priv(cdev);
38 
39 	return readl(priv->base + reg);
40 }
41 
42 static int iomap_read_fifo(struct m_can_classdev *cdev, int offset, void *val, size_t val_count)
43 {
44 	struct m_can_pci_priv *priv = cdev_to_priv(cdev);
45 
46 	ioread32_rep(priv->base + offset, val, val_count);
47 
48 	return 0;
49 }
50 
51 static int iomap_write_reg(struct m_can_classdev *cdev, int reg, int val)
52 {
53 	struct m_can_pci_priv *priv = cdev_to_priv(cdev);
54 
55 	writel(val, priv->base + reg);
56 
57 	return 0;
58 }
59 
60 static int iomap_write_fifo(struct m_can_classdev *cdev, int offset,
61 			    const void *val, size_t val_count)
62 {
63 	struct m_can_pci_priv *priv = cdev_to_priv(cdev);
64 
65 	iowrite32_rep(priv->base + offset, val, val_count);
66 
67 	return 0;
68 }
69 
70 static struct m_can_ops m_can_pci_ops = {
71 	.read_reg = iomap_read_reg,
72 	.write_reg = iomap_write_reg,
73 	.write_fifo = iomap_write_fifo,
74 	.read_fifo = iomap_read_fifo,
75 };
76 
77 static int m_can_pci_probe(struct pci_dev *pci, const struct pci_device_id *id)
78 {
79 	struct device *dev = &pci->dev;
80 	struct m_can_classdev *mcan_class;
81 	struct m_can_pci_priv *priv;
82 	void __iomem *base;
83 	int ret;
84 
85 	ret = pcim_enable_device(pci);
86 	if (ret)
87 		return ret;
88 
89 	pci_set_master(pci);
90 
91 	ret = pcim_iomap_regions(pci, BIT(M_CAN_PCI_MMIO_BAR), pci_name(pci));
92 	if (ret)
93 		return ret;
94 
95 	base = pcim_iomap_table(pci)[M_CAN_PCI_MMIO_BAR];
96 
97 	if (!base) {
98 		dev_err(dev, "failed to map BARs\n");
99 		return -ENOMEM;
100 	}
101 
102 	mcan_class = m_can_class_allocate_dev(&pci->dev,
103 					      sizeof(struct m_can_pci_priv));
104 	if (!mcan_class)
105 		return -ENOMEM;
106 
107 	priv = cdev_to_priv(mcan_class);
108 
109 	priv->base = base;
110 
111 	ret = pci_alloc_irq_vectors(pci, 1, 1, PCI_IRQ_ALL_TYPES);
112 	if (ret < 0)
113 		return ret;
114 
115 	mcan_class->dev = &pci->dev;
116 	mcan_class->net->irq = pci_irq_vector(pci, 0);
117 	mcan_class->pm_clock_support = 1;
118 	mcan_class->can.clock.freq = id->driver_data;
119 	mcan_class->ops = &m_can_pci_ops;
120 
121 	pci_set_drvdata(pci, mcan_class);
122 
123 	ret = m_can_class_register(mcan_class);
124 	if (ret)
125 		goto err;
126 
127 	/* Enable interrupt control at CAN wrapper IP */
128 	writel(0x1, base + CTL_CSR_INT_CTL_OFFSET);
129 
130 	pm_runtime_set_autosuspend_delay(dev, 1000);
131 	pm_runtime_use_autosuspend(dev);
132 	pm_runtime_put_noidle(dev);
133 	pm_runtime_allow(dev);
134 
135 	return 0;
136 
137 err:
138 	pci_free_irq_vectors(pci);
139 	return ret;
140 }
141 
142 static void m_can_pci_remove(struct pci_dev *pci)
143 {
144 	struct m_can_classdev *mcan_class = pci_get_drvdata(pci);
145 	struct m_can_pci_priv *priv = cdev_to_priv(mcan_class);
146 
147 	pm_runtime_forbid(&pci->dev);
148 	pm_runtime_get_noresume(&pci->dev);
149 
150 	/* Disable interrupt control at CAN wrapper IP */
151 	writel(0x0, priv->base + CTL_CSR_INT_CTL_OFFSET);
152 
153 	m_can_class_unregister(mcan_class);
154 	pci_free_irq_vectors(pci);
155 }
156 
157 static __maybe_unused int m_can_pci_suspend(struct device *dev)
158 {
159 	return m_can_class_suspend(dev);
160 }
161 
162 static __maybe_unused int m_can_pci_resume(struct device *dev)
163 {
164 	return m_can_class_resume(dev);
165 }
166 
167 static SIMPLE_DEV_PM_OPS(m_can_pci_pm_ops,
168 			 m_can_pci_suspend, m_can_pci_resume);
169 
170 static const struct pci_device_id m_can_pci_id_table[] = {
171 	{ PCI_VDEVICE(INTEL, 0x4bc1), M_CAN_CLOCK_FREQ_EHL, },
172 	{ PCI_VDEVICE(INTEL, 0x4bc2), M_CAN_CLOCK_FREQ_EHL, },
173 	{  }	/* Terminating Entry */
174 };
175 MODULE_DEVICE_TABLE(pci, m_can_pci_id_table);
176 
177 static struct pci_driver m_can_pci_driver = {
178 	.name = "m_can_pci",
179 	.probe = m_can_pci_probe,
180 	.remove = m_can_pci_remove,
181 	.id_table = m_can_pci_id_table,
182 	.driver = {
183 		.pm = &m_can_pci_pm_ops,
184 	},
185 };
186 
187 module_pci_driver(m_can_pci_driver);
188 
189 MODULE_AUTHOR("Felipe Balbi (Intel)");
190 MODULE_AUTHOR("Jarkko Nikula <jarkko.nikula@linux.intel.com>");
191 MODULE_AUTHOR("Raymond Tan <raymond.tan@intel.com>");
192 MODULE_LICENSE("GPL");
193 MODULE_DESCRIPTION("CAN bus driver for Bosch M_CAN controller on PCI bus");
194