1 // SPDX-License-Identifier: GPL-2.0-only 2 #include <stdint.h> 3 #include <unistd.h> 4 5 #include <linux/errno.h> 6 #include <linux/io.h> 7 #include <linux/pci_ids.h> 8 #include <linux/sizes.h> 9 10 #include <vfio_util.h> 11 12 #include "hw.h" 13 #include "registers.h" 14 15 #define IOAT_DMACOUNT_MAX UINT16_MAX 16 17 struct ioat_state { 18 /* Single descriptor used to issue DMA memcpy operations */ 19 struct ioat_dma_descriptor desc; 20 21 /* Copy buffers used by ioat_send_msi() to generate an interrupt. */ 22 u64 send_msi_src; 23 u64 send_msi_dst; 24 }; 25 26 static inline struct ioat_state *to_ioat_state(struct vfio_pci_device *device) 27 { 28 return device->driver.region.vaddr; 29 } 30 31 static inline void *ioat_channel_registers(struct vfio_pci_device *device) 32 { 33 return device->bars[0].vaddr + IOAT_CHANNEL_MMIO_SIZE; 34 } 35 36 static int ioat_probe(struct vfio_pci_device *device) 37 { 38 u8 version; 39 int r; 40 41 if (!vfio_pci_device_match(device, PCI_VENDOR_ID_INTEL, 42 PCI_DEVICE_ID_INTEL_IOAT_SKX)) 43 return -EINVAL; 44 45 VFIO_ASSERT_NOT_NULL(device->bars[0].vaddr); 46 47 version = readb(device->bars[0].vaddr + IOAT_VER_OFFSET); 48 switch (version) { 49 case IOAT_VER_3_2: 50 case IOAT_VER_3_3: 51 r = 0; 52 break; 53 default: 54 printf("ioat: Unsupported version: 0x%x\n", version); 55 r = -EINVAL; 56 } 57 return r; 58 } 59 60 static u64 ioat_channel_status(void *bar) 61 { 62 return readq(bar + IOAT_CHANSTS_OFFSET) & IOAT_CHANSTS_STATUS; 63 } 64 65 static void ioat_clear_errors(struct vfio_pci_device *device) 66 { 67 void *registers = ioat_channel_registers(device); 68 u32 errors; 69 70 errors = vfio_pci_config_readl(device, IOAT_PCI_CHANERR_INT_OFFSET); 71 vfio_pci_config_writel(device, IOAT_PCI_CHANERR_INT_OFFSET, errors); 72 73 errors = vfio_pci_config_readl(device, IOAT_PCI_DMAUNCERRSTS_OFFSET); 74 vfio_pci_config_writel(device, IOAT_PCI_CHANERR_INT_OFFSET, errors); 75 76 errors = readl(registers + IOAT_CHANERR_OFFSET); 77 writel(errors, registers + IOAT_CHANERR_OFFSET); 78 } 79 80 static void ioat_reset(struct vfio_pci_device *device) 81 { 82 void *registers = ioat_channel_registers(device); 83 u32 sleep_ms = 1, attempts = 5000 / sleep_ms; 84 u8 chancmd; 85 86 ioat_clear_errors(device); 87 88 writeb(IOAT_CHANCMD_RESET, registers + IOAT2_CHANCMD_OFFSET); 89 90 for (;;) { 91 chancmd = readb(registers + IOAT2_CHANCMD_OFFSET); 92 if (!(chancmd & IOAT_CHANCMD_RESET)) 93 break; 94 95 VFIO_ASSERT_GT(--attempts, 0); 96 usleep(sleep_ms * 1000); 97 } 98 99 VFIO_ASSERT_EQ(ioat_channel_status(registers), IOAT_CHANSTS_HALTED); 100 } 101 102 static void ioat_init(struct vfio_pci_device *device) 103 { 104 struct ioat_state *ioat = to_ioat_state(device); 105 u8 intrctrl; 106 107 VFIO_ASSERT_GE(device->driver.region.size, sizeof(*ioat)); 108 109 vfio_pci_config_writew(device, PCI_COMMAND, 110 PCI_COMMAND_MEMORY | 111 PCI_COMMAND_MASTER | 112 PCI_COMMAND_INTX_DISABLE); 113 114 ioat_reset(device); 115 116 /* Enable the use of MXI-x interrupts for channel interrupts. */ 117 intrctrl = IOAT_INTRCTRL_MSIX_VECTOR_CONTROL; 118 writeb(intrctrl, device->bars[0].vaddr + IOAT_INTRCTRL_OFFSET); 119 120 vfio_pci_msix_enable(device, 0, device->msix_info.count); 121 122 device->driver.msi = 0; 123 device->driver.max_memcpy_size = 124 1UL << readb(device->bars[0].vaddr + IOAT_XFERCAP_OFFSET); 125 device->driver.max_memcpy_count = IOAT_DMACOUNT_MAX; 126 } 127 128 static void ioat_remove(struct vfio_pci_device *device) 129 { 130 ioat_reset(device); 131 vfio_pci_msix_disable(device); 132 } 133 134 static void ioat_handle_error(struct vfio_pci_device *device) 135 { 136 void *registers = ioat_channel_registers(device); 137 138 printf("Error detected during memcpy operation!\n" 139 " CHANERR: 0x%x\n" 140 " CHANERR_INT: 0x%x\n" 141 " DMAUNCERRSTS: 0x%x\n", 142 readl(registers + IOAT_CHANERR_OFFSET), 143 vfio_pci_config_readl(device, IOAT_PCI_CHANERR_INT_OFFSET), 144 vfio_pci_config_readl(device, IOAT_PCI_DMAUNCERRSTS_OFFSET)); 145 146 ioat_reset(device); 147 } 148 149 static int ioat_memcpy_wait(struct vfio_pci_device *device) 150 { 151 void *registers = ioat_channel_registers(device); 152 u64 status; 153 int r = 0; 154 155 /* Wait until all operations complete. */ 156 for (;;) { 157 status = ioat_channel_status(registers); 158 if (status == IOAT_CHANSTS_DONE) 159 break; 160 161 if (status == IOAT_CHANSTS_HALTED) { 162 ioat_handle_error(device); 163 return -1; 164 } 165 } 166 167 /* Put the channel into the SUSPENDED state. */ 168 writeb(IOAT_CHANCMD_SUSPEND, registers + IOAT2_CHANCMD_OFFSET); 169 for (;;) { 170 status = ioat_channel_status(registers); 171 if (status == IOAT_CHANSTS_SUSPENDED) 172 break; 173 } 174 175 return r; 176 } 177 178 static void __ioat_memcpy_start(struct vfio_pci_device *device, 179 iova_t src, iova_t dst, u64 size, 180 u16 count, bool interrupt) 181 { 182 void *registers = ioat_channel_registers(device); 183 struct ioat_state *ioat = to_ioat_state(device); 184 u64 desc_iova; 185 u16 chanctrl; 186 187 desc_iova = to_iova(device, &ioat->desc); 188 ioat->desc = (struct ioat_dma_descriptor) { 189 .ctl_f.op = IOAT_OP_COPY, 190 .ctl_f.int_en = interrupt, 191 .src_addr = src, 192 .dst_addr = dst, 193 .size = size, 194 .next = desc_iova, 195 }; 196 197 /* Tell the device the address of the descriptor. */ 198 writeq(desc_iova, registers + IOAT2_CHAINADDR_OFFSET); 199 200 /* (Re)Enable the channel interrupt and abort on any errors */ 201 chanctrl = IOAT_CHANCTRL_INT_REARM | IOAT_CHANCTRL_ANY_ERR_ABORT_EN; 202 writew(chanctrl, registers + IOAT_CHANCTRL_OFFSET); 203 204 /* Kick off @count DMA copy operation(s). */ 205 writew(count, registers + IOAT_CHAN_DMACOUNT_OFFSET); 206 } 207 208 static void ioat_memcpy_start(struct vfio_pci_device *device, 209 iova_t src, iova_t dst, u64 size, 210 u64 count) 211 { 212 __ioat_memcpy_start(device, src, dst, size, count, false); 213 } 214 215 static void ioat_send_msi(struct vfio_pci_device *device) 216 { 217 struct ioat_state *ioat = to_ioat_state(device); 218 219 __ioat_memcpy_start(device, 220 to_iova(device, &ioat->send_msi_src), 221 to_iova(device, &ioat->send_msi_dst), 222 sizeof(ioat->send_msi_src), 1, true); 223 224 VFIO_ASSERT_EQ(ioat_memcpy_wait(device), 0); 225 } 226 227 const struct vfio_pci_driver_ops ioat_ops = { 228 .name = "ioat", 229 .probe = ioat_probe, 230 .init = ioat_init, 231 .remove = ioat_remove, 232 .memcpy_start = ioat_memcpy_start, 233 .memcpy_wait = ioat_memcpy_wait, 234 .send_msi = ioat_send_msi, 235 }; 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