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 const 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 goto err_free_dev; 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->pm_wake_source = 0; 129 mcan_class->can.clock.freq = id->driver_data; 130 mcan_class->ops = &m_can_pci_ops; 131 132 pci_set_drvdata(pci, mcan_class); 133 134 ret = m_can_class_register(mcan_class); 135 if (ret) 136 goto err_free_irq; 137 138 /* Enable interrupt control at CAN wrapper IP */ 139 writel(0x1, base + CTL_CSR_INT_CTL_OFFSET); 140 141 pm_runtime_set_autosuspend_delay(dev, 1000); 142 pm_runtime_use_autosuspend(dev); 143 pm_runtime_put_noidle(dev); 144 pm_runtime_allow(dev); 145 146 return 0; 147 148 err_free_irq: 149 pci_free_irq_vectors(pci); 150 err_free_dev: 151 m_can_class_free_dev(mcan_class->net); 152 return ret; 153 } 154 155 static void m_can_pci_remove(struct pci_dev *pci) 156 { 157 struct m_can_classdev *mcan_class = pci_get_drvdata(pci); 158 struct m_can_pci_priv *priv = cdev_to_priv(mcan_class); 159 160 pm_runtime_forbid(&pci->dev); 161 pm_runtime_get_noresume(&pci->dev); 162 163 /* Disable interrupt control at CAN wrapper IP */ 164 writel(0x0, priv->base + CTL_CSR_INT_CTL_OFFSET); 165 166 m_can_class_unregister(mcan_class); 167 m_can_class_free_dev(mcan_class->net); 168 pci_free_irq_vectors(pci); 169 } 170 171 static __maybe_unused int m_can_pci_suspend(struct device *dev) 172 { 173 return m_can_class_suspend(dev); 174 } 175 176 static __maybe_unused int m_can_pci_resume(struct device *dev) 177 { 178 return m_can_class_resume(dev); 179 } 180 181 static SIMPLE_DEV_PM_OPS(m_can_pci_pm_ops, 182 m_can_pci_suspend, m_can_pci_resume); 183 184 static const struct pci_device_id m_can_pci_id_table[] = { 185 { PCI_VDEVICE(INTEL, 0x4bc1), M_CAN_CLOCK_FREQ_EHL, }, 186 { PCI_VDEVICE(INTEL, 0x4bc2), M_CAN_CLOCK_FREQ_EHL, }, 187 { } /* Terminating Entry */ 188 }; 189 MODULE_DEVICE_TABLE(pci, m_can_pci_id_table); 190 191 static struct pci_driver m_can_pci_driver = { 192 .name = "m_can_pci", 193 .probe = m_can_pci_probe, 194 .remove = m_can_pci_remove, 195 .id_table = m_can_pci_id_table, 196 .driver = { 197 .pm = &m_can_pci_pm_ops, 198 }, 199 }; 200 201 module_pci_driver(m_can_pci_driver); 202 203 MODULE_AUTHOR("Felipe Balbi (Intel)"); 204 MODULE_AUTHOR("Jarkko Nikula <jarkko.nikula@linux.intel.com>"); 205 MODULE_AUTHOR("Raymond Tan <raymond.tan@intel.com>"); 206 MODULE_LICENSE("GPL"); 207 MODULE_DESCRIPTION("CAN bus driver for Bosch M_CAN controller on PCI bus"); 208