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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * AMD Passthru DMA device driver4 * -- Based on the CCP driver5 *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 26struct 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 struct33 *34 * @dev: device struct of the PTDMA35 */36static 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 51static 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 71static 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 86static 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 107static 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 121static 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 199e_err:200 dev_err(dev, "initialization failed ret = %d\n", ret);201 202 return ret;203}204 205static 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 219static const struct pt_dev_vdata dev_vdata[] = {220 {221 .bar = 2,222 },223};224 225static 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};230MODULE_DEVICE_TABLE(pci, pt_pci_table);231 232static 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 239module_pci_driver(pt_pci_driver);240 241MODULE_AUTHOR("Sanjay R Mehta <sanju.mehta@amd.com>");242MODULE_LICENSE("GPL");243MODULE_DESCRIPTION("AMD PassThru DMA driver");244