1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * AMD Passthru DMA device driver 4 * -- Based on the CCP driver 5 * 6 * Copyright (C) 2016,2021 Advanced Micro Devices, Inc. 7 * 8 * Author: Sanjay R Mehta <sanju.mehta@amd.com> 9 * Author: Tom Lendacky <thomas.lendacky@amd.com> 10 * Author: Gary R Hook <gary.hook@amd.com> 11 */ 12 13 #include <linux/device.h> 14 #include <linux/dma-mapping.h> 15 #include <linux/delay.h> 16 #include <linux/interrupt.h> 17 #include <linux/kernel.h> 18 #include <linux/kthread.h> 19 #include <linux/module.h> 20 #include <linux/pci_ids.h> 21 #include <linux/pci.h> 22 #include <linux/spinlock.h> 23 24 #include "ptdma.h" 25 26 struct pt_msix { 27 int msix_count; 28 struct msix_entry msix_entry; 29 }; 30 31 /* 32 * pt_alloc_struct - allocate and initialize the pt_device struct 33 * 34 * @dev: device struct of the PTDMA 35 */ 36 static struct pt_device *pt_alloc_struct(struct device *dev) 37 { 38 struct pt_device *pt; 39 40 pt = devm_kzalloc(dev, sizeof(*pt), GFP_KERNEL); 41 42 if (!pt) 43 return NULL; 44 pt->dev = dev; 45 46 INIT_LIST_HEAD(&pt->cmd); 47 48 return pt; 49 } 50 51 static int pt_get_msix_irqs(struct pt_device *pt) 52 { 53 struct pt_msix *pt_msix = pt->pt_msix; 54 struct device *dev = pt->dev; 55 struct pci_dev *pdev = to_pci_dev(dev); 56 int ret; 57 58 pt_msix->msix_entry.entry = 0; 59 60 ret = pci_enable_msix_range(pdev, &pt_msix->msix_entry, 1, 1); 61 if (ret < 0) 62 return ret; 63 64 pt_msix->msix_count = ret; 65 66 pt->pt_irq = pt_msix->msix_entry.vector; 67 68 return 0; 69 } 70 71 static int pt_get_msi_irq(struct pt_device *pt) 72 { 73 struct device *dev = pt->dev; 74 struct pci_dev *pdev = to_pci_dev(dev); 75 int ret; 76 77 ret = pci_enable_msi(pdev); 78 if (ret) 79 return ret; 80 81 pt->pt_irq = pdev->irq; 82 83 return 0; 84 } 85 86 static int pt_get_irqs(struct pt_device *pt) 87 { 88 struct device *dev = pt->dev; 89 int ret; 90 91 ret = pt_get_msix_irqs(pt); 92 if (!ret) 93 return 0; 94 95 /* Couldn't get MSI-X vectors, try MSI */ 96 dev_err(dev, "could not enable MSI-X (%d), trying MSI\n", ret); 97 ret = pt_get_msi_irq(pt); 98 if (!ret) 99 return 0; 100 101 /* Couldn't get MSI interrupt */ 102 dev_err(dev, "could not enable MSI (%d)\n", ret); 103 104 return ret; 105 } 106 107 static void pt_free_irqs(struct pt_device *pt) 108 { 109 struct pt_msix *pt_msix = pt->pt_msix; 110 struct device *dev = pt->dev; 111 struct pci_dev *pdev = to_pci_dev(dev); 112 113 if (pt_msix->msix_count) 114 pci_disable_msix(pdev); 115 else if (pt->pt_irq) 116 pci_disable_msi(pdev); 117 118 pt->pt_irq = 0; 119 } 120 121 static int pt_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) 122 { 123 struct pt_device *pt; 124 struct pt_msix *pt_msix; 125 struct device *dev = &pdev->dev; 126 void __iomem * const *iomap_table; 127 int bar_mask; 128 int ret = -ENOMEM; 129 130 pt = pt_alloc_struct(dev); 131 if (!pt) 132 goto e_err; 133 134 pt_msix = devm_kzalloc(dev, sizeof(*pt_msix), GFP_KERNEL); 135 if (!pt_msix) 136 goto e_err; 137 138 pt->pt_msix = pt_msix; 139 pt->dev_vdata = (struct pt_dev_vdata *)id->driver_data; 140 if (!pt->dev_vdata) { 141 ret = -ENODEV; 142 dev_err(dev, "missing driver data\n"); 143 goto e_err; 144 } 145 146 ret = pcim_enable_device(pdev); 147 if (ret) { 148 dev_err(dev, "pcim_enable_device failed (%d)\n", ret); 149 goto e_err; 150 } 151 152 bar_mask = pci_select_bars(pdev, IORESOURCE_MEM); 153 ret = pcim_iomap_regions(pdev, bar_mask, "ptdma"); 154 if (ret) { 155 dev_err(dev, "pcim_iomap_regions failed (%d)\n", ret); 156 goto e_err; 157 } 158 159 iomap_table = pcim_iomap_table(pdev); 160 if (!iomap_table) { 161 dev_err(dev, "pcim_iomap_table failed\n"); 162 ret = -ENOMEM; 163 goto e_err; 164 } 165 166 pt->io_regs = iomap_table[pt->dev_vdata->bar]; 167 if (!pt->io_regs) { 168 dev_err(dev, "ioremap failed\n"); 169 ret = -ENOMEM; 170 goto e_err; 171 } 172 173 ret = pt_get_irqs(pt); 174 if (ret) 175 goto e_err; 176 177 pci_set_master(pdev); 178 179 ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(48)); 180 if (ret) { 181 ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32)); 182 if (ret) { 183 dev_err(dev, "dma_set_mask_and_coherent failed (%d)\n", 184 ret); 185 goto e_err; 186 } 187 } 188 189 dev_set_drvdata(dev, pt); 190 191 if (pt->dev_vdata) 192 ret = pt_core_init(pt); 193 194 if (ret) 195 goto e_err; 196 197 return 0; 198 199 e_err: 200 dev_err(dev, "initialization failed ret = %d\n", ret); 201 202 return ret; 203 } 204 205 static void pt_pci_remove(struct pci_dev *pdev) 206 { 207 struct device *dev = &pdev->dev; 208 struct pt_device *pt = dev_get_drvdata(dev); 209 210 if (!pt) 211 return; 212 213 if (pt->dev_vdata) 214 pt_core_destroy(pt); 215 216 pt_free_irqs(pt); 217 } 218 219 static const struct pt_dev_vdata dev_vdata[] = { 220 { 221 .bar = 2, 222 }, 223 }; 224 225 static const struct pci_device_id pt_pci_table[] = { 226 { PCI_VDEVICE(AMD, 0x1498), (kernel_ulong_t)&dev_vdata[0] }, 227 /* Last entry must be zero */ 228 { 0, } 229 }; 230 MODULE_DEVICE_TABLE(pci, pt_pci_table); 231 232 static struct pci_driver pt_pci_driver = { 233 .name = "ptdma", 234 .id_table = pt_pci_table, 235 .probe = pt_pci_probe, 236 .remove = pt_pci_remove, 237 }; 238 239 module_pci_driver(pt_pci_driver); 240 241 MODULE_AUTHOR("Sanjay R Mehta <sanju.mehta@amd.com>"); 242 MODULE_LICENSE("GPL"); 243 MODULE_DESCRIPTION("AMD PassThru DMA driver"); 244