xref: /openbmc/linux/drivers/net/can/m_can/m_can_pci.c (revision 9a29f5fc)
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		200000000
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 	void __iomem *src = priv->base + offset;
46 
47 	while (val_count--) {
48 		*(unsigned int *)val = ioread32(src);
49 		val += 4;
50 		src += 4;
51 	}
52 
53 	return 0;
54 }
55 
56 static int iomap_write_reg(struct m_can_classdev *cdev, int reg, int val)
57 {
58 	struct m_can_pci_priv *priv = cdev_to_priv(cdev);
59 
60 	writel(val, priv->base + reg);
61 
62 	return 0;
63 }
64 
65 static int iomap_write_fifo(struct m_can_classdev *cdev, int offset,
66 			    const void *val, size_t val_count)
67 {
68 	struct m_can_pci_priv *priv = cdev_to_priv(cdev);
69 	void __iomem *dst = priv->base + offset;
70 
71 	while (val_count--) {
72 		iowrite32(*(unsigned int *)val, dst);
73 		val += 4;
74 		dst += 4;
75 	}
76 
77 	return 0;
78 }
79 
80 static struct m_can_ops m_can_pci_ops = {
81 	.read_reg = iomap_read_reg,
82 	.write_reg = iomap_write_reg,
83 	.write_fifo = iomap_write_fifo,
84 	.read_fifo = iomap_read_fifo,
85 };
86 
87 static int m_can_pci_probe(struct pci_dev *pci, const struct pci_device_id *id)
88 {
89 	struct device *dev = &pci->dev;
90 	struct m_can_classdev *mcan_class;
91 	struct m_can_pci_priv *priv;
92 	void __iomem *base;
93 	int ret;
94 
95 	ret = pcim_enable_device(pci);
96 	if (ret)
97 		return ret;
98 
99 	pci_set_master(pci);
100 
101 	ret = pcim_iomap_regions(pci, BIT(M_CAN_PCI_MMIO_BAR), pci_name(pci));
102 	if (ret)
103 		return ret;
104 
105 	base = pcim_iomap_table(pci)[M_CAN_PCI_MMIO_BAR];
106 
107 	if (!base) {
108 		dev_err(dev, "failed to map BARs\n");
109 		return -ENOMEM;
110 	}
111 
112 	mcan_class = m_can_class_allocate_dev(&pci->dev,
113 					      sizeof(struct m_can_pci_priv));
114 	if (!mcan_class)
115 		return -ENOMEM;
116 
117 	priv = cdev_to_priv(mcan_class);
118 
119 	priv->base = base;
120 
121 	ret = pci_alloc_irq_vectors(pci, 1, 1, PCI_IRQ_ALL_TYPES);
122 	if (ret < 0)
123 		return ret;
124 
125 	mcan_class->dev = &pci->dev;
126 	mcan_class->net->irq = pci_irq_vector(pci, 0);
127 	mcan_class->pm_clock_support = 1;
128 	mcan_class->can.clock.freq = id->driver_data;
129 	mcan_class->ops = &m_can_pci_ops;
130 
131 	pci_set_drvdata(pci, mcan_class);
132 
133 	ret = m_can_class_register(mcan_class);
134 	if (ret)
135 		goto err;
136 
137 	/* Enable interrupt control at CAN wrapper IP */
138 	writel(0x1, base + CTL_CSR_INT_CTL_OFFSET);
139 
140 	pm_runtime_set_autosuspend_delay(dev, 1000);
141 	pm_runtime_use_autosuspend(dev);
142 	pm_runtime_put_noidle(dev);
143 	pm_runtime_allow(dev);
144 
145 	return 0;
146 
147 err:
148 	pci_free_irq_vectors(pci);
149 	return ret;
150 }
151 
152 static void m_can_pci_remove(struct pci_dev *pci)
153 {
154 	struct m_can_classdev *mcan_class = pci_get_drvdata(pci);
155 	struct m_can_pci_priv *priv = cdev_to_priv(mcan_class);
156 
157 	pm_runtime_forbid(&pci->dev);
158 	pm_runtime_get_noresume(&pci->dev);
159 
160 	/* Disable interrupt control at CAN wrapper IP */
161 	writel(0x0, priv->base + CTL_CSR_INT_CTL_OFFSET);
162 
163 	m_can_class_unregister(mcan_class);
164 	pci_free_irq_vectors(pci);
165 }
166 
167 static __maybe_unused int m_can_pci_suspend(struct device *dev)
168 {
169 	return m_can_class_suspend(dev);
170 }
171 
172 static __maybe_unused int m_can_pci_resume(struct device *dev)
173 {
174 	return m_can_class_resume(dev);
175 }
176 
177 static SIMPLE_DEV_PM_OPS(m_can_pci_pm_ops,
178 			 m_can_pci_suspend, m_can_pci_resume);
179 
180 static const struct pci_device_id m_can_pci_id_table[] = {
181 	{ PCI_VDEVICE(INTEL, 0x4bc1), M_CAN_CLOCK_FREQ_EHL, },
182 	{ PCI_VDEVICE(INTEL, 0x4bc2), M_CAN_CLOCK_FREQ_EHL, },
183 	{  }	/* Terminating Entry */
184 };
185 MODULE_DEVICE_TABLE(pci, m_can_pci_id_table);
186 
187 static struct pci_driver m_can_pci_driver = {
188 	.name = "m_can_pci",
189 	.probe = m_can_pci_probe,
190 	.remove = m_can_pci_remove,
191 	.id_table = m_can_pci_id_table,
192 	.driver = {
193 		.pm = &m_can_pci_pm_ops,
194 	},
195 };
196 
197 module_pci_driver(m_can_pci_driver);
198 
199 MODULE_AUTHOR("Felipe Balbi (Intel)");
200 MODULE_AUTHOR("Jarkko Nikula <jarkko.nikula@linux.intel.com>");
201 MODULE_AUTHOR("Raymond Tan <raymond.tan@intel.com>");
202 MODULE_LICENSE("GPL");
203 MODULE_DESCRIPTION("CAN bus driver for Bosch M_CAN controller on PCI bus");
204