1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2005-2008, PA Semi, Inc 4 * 5 * Maintained by: Olof Johansson <olof@lixom.net> 6 */ 7 8 #undef DEBUG 9 10 #include <linux/memblock.h> 11 #include <linux/types.h> 12 #include <linux/spinlock.h> 13 #include <linux/pci.h> 14 #include <asm/iommu.h> 15 #include <asm/machdep.h> 16 #include <asm/firmware.h> 17 18 #include "pasemi.h" 19 20 #define IOBMAP_PAGE_SHIFT 12 21 #define IOBMAP_PAGE_SIZE (1 << IOBMAP_PAGE_SHIFT) 22 #define IOBMAP_PAGE_MASK (IOBMAP_PAGE_SIZE - 1) 23 24 #define IOB_BASE 0xe0000000 25 #define IOB_SIZE 0x3000 26 /* Configuration registers */ 27 #define IOBCAP_REG 0x40 28 #define IOBCOM_REG 0x100 29 /* Enable IOB address translation */ 30 #define IOBCOM_ATEN 0x00000100 31 32 /* Address decode configuration register */ 33 #define IOB_AD_REG 0x14c 34 /* IOBCOM_AD_REG fields */ 35 #define IOB_AD_VGPRT 0x00000e00 36 #define IOB_AD_VGAEN 0x00000100 37 /* Direct mapping settings */ 38 #define IOB_AD_MPSEL_MASK 0x00000030 39 #define IOB_AD_MPSEL_B38 0x00000000 40 #define IOB_AD_MPSEL_B40 0x00000010 41 #define IOB_AD_MPSEL_B42 0x00000020 42 /* Translation window size / enable */ 43 #define IOB_AD_TRNG_MASK 0x00000003 44 #define IOB_AD_TRNG_256M 0x00000000 45 #define IOB_AD_TRNG_2G 0x00000001 46 #define IOB_AD_TRNG_128G 0x00000003 47 48 #define IOB_TABLEBASE_REG 0x154 49 50 /* Base of the 64 4-byte L1 registers */ 51 #define IOB_XLT_L1_REGBASE 0x2b00 52 53 /* Register to invalidate TLB entries */ 54 #define IOB_AT_INVAL_TLB_REG 0x2d00 55 56 /* The top two bits of the level 1 entry contains valid and type flags */ 57 #define IOBMAP_L1E_V 0x40000000 58 #define IOBMAP_L1E_V_B 0x80000000 59 60 /* For big page entries, the bottom two bits contains flags */ 61 #define IOBMAP_L1E_BIG_CACHED 0x00000002 62 #define IOBMAP_L1E_BIG_PRIORITY 0x00000001 63 64 /* For regular level 2 entries, top 2 bits contain valid and cache flags */ 65 #define IOBMAP_L2E_V 0x80000000 66 #define IOBMAP_L2E_V_CACHED 0xc0000000 67 68 static void __iomem *iob; 69 static u32 iob_l1_emptyval; 70 static u32 iob_l2_emptyval; 71 static u32 *iob_l2_base; 72 73 static struct iommu_table iommu_table_iobmap; 74 static int iommu_table_iobmap_inited; 75 76 static int iobmap_build(struct iommu_table *tbl, long index, 77 long npages, unsigned long uaddr, 78 enum dma_data_direction direction, 79 unsigned long attrs) 80 { 81 u32 *ip; 82 u32 rpn; 83 unsigned long bus_addr; 84 85 pr_debug("iobmap: build at: %lx, %lx, addr: %lx\n", index, npages, uaddr); 86 87 bus_addr = (tbl->it_offset + index) << IOBMAP_PAGE_SHIFT; 88 89 ip = ((u32 *)tbl->it_base) + index; 90 91 while (npages--) { 92 rpn = __pa(uaddr) >> IOBMAP_PAGE_SHIFT; 93 94 *(ip++) = IOBMAP_L2E_V | rpn; 95 /* invalidate tlb, can be optimized more */ 96 out_le32(iob+IOB_AT_INVAL_TLB_REG, bus_addr >> 14); 97 98 uaddr += IOBMAP_PAGE_SIZE; 99 bus_addr += IOBMAP_PAGE_SIZE; 100 } 101 return 0; 102 } 103 104 105 static void iobmap_free(struct iommu_table *tbl, long index, 106 long npages) 107 { 108 u32 *ip; 109 unsigned long bus_addr; 110 111 pr_debug("iobmap: free at: %lx, %lx\n", index, npages); 112 113 bus_addr = (tbl->it_offset + index) << IOBMAP_PAGE_SHIFT; 114 115 ip = ((u32 *)tbl->it_base) + index; 116 117 while (npages--) { 118 *(ip++) = iob_l2_emptyval; 119 /* invalidate tlb, can be optimized more */ 120 out_le32(iob+IOB_AT_INVAL_TLB_REG, bus_addr >> 14); 121 bus_addr += IOBMAP_PAGE_SIZE; 122 } 123 } 124 125 static struct iommu_table_ops iommu_table_iobmap_ops = { 126 .set = iobmap_build, 127 .clear = iobmap_free 128 }; 129 130 static void iommu_table_iobmap_setup(void) 131 { 132 pr_debug(" -> %s\n", __func__); 133 iommu_table_iobmap.it_busno = 0; 134 iommu_table_iobmap.it_offset = 0; 135 iommu_table_iobmap.it_page_shift = IOBMAP_PAGE_SHIFT; 136 137 /* it_size is in number of entries */ 138 iommu_table_iobmap.it_size = 139 0x80000000 >> iommu_table_iobmap.it_page_shift; 140 141 /* Initialize the common IOMMU code */ 142 iommu_table_iobmap.it_base = (unsigned long)iob_l2_base; 143 iommu_table_iobmap.it_index = 0; 144 /* XXXOJN tune this to avoid IOB cache invals. 145 * Should probably be 8 (64 bytes) 146 */ 147 iommu_table_iobmap.it_blocksize = 4; 148 iommu_table_iobmap.it_ops = &iommu_table_iobmap_ops; 149 iommu_init_table(&iommu_table_iobmap, 0); 150 pr_debug(" <- %s\n", __func__); 151 } 152 153 154 155 static void pci_dma_bus_setup_pasemi(struct pci_bus *bus) 156 { 157 pr_debug("pci_dma_bus_setup, bus %p, bus->self %p\n", bus, bus->self); 158 159 if (!iommu_table_iobmap_inited) { 160 iommu_table_iobmap_inited = 1; 161 iommu_table_iobmap_setup(); 162 } 163 } 164 165 166 static void pci_dma_dev_setup_pasemi(struct pci_dev *dev) 167 { 168 pr_debug("pci_dma_dev_setup, dev %p (%s)\n", dev, pci_name(dev)); 169 170 #if !defined(CONFIG_PPC_PASEMI_IOMMU_DMA_FORCE) 171 /* For non-LPAR environment, don't translate anything for the DMA 172 * engine. The exception to this is if the user has enabled 173 * CONFIG_PPC_PASEMI_IOMMU_DMA_FORCE at build time. 174 */ 175 if (dev->vendor == 0x1959 && dev->device == 0xa007 && 176 !firmware_has_feature(FW_FEATURE_LPAR)) { 177 dev->dev.dma_ops = NULL; 178 /* 179 * Set the coherent DMA mask to prevent the iommu 180 * being used unnecessarily 181 */ 182 dev->dev.coherent_dma_mask = DMA_BIT_MASK(44); 183 return; 184 } 185 #endif 186 187 set_iommu_table_base(&dev->dev, &iommu_table_iobmap); 188 } 189 190 static int __init iob_init(struct device_node *dn) 191 { 192 unsigned long tmp; 193 u32 regword; 194 int i; 195 196 pr_debug(" -> %s\n", __func__); 197 198 /* For 2G space, 8x64 pages (2^21 bytes) is max total l2 size */ 199 iob_l2_base = memblock_alloc_try_nid_raw(1UL << 21, 1UL << 21, 200 MEMBLOCK_LOW_LIMIT, 0x80000000, 201 NUMA_NO_NODE); 202 if (!iob_l2_base) 203 panic("%s: Failed to allocate %lu bytes align=0x%lx max_addr=%x\n", 204 __func__, 1UL << 21, 1UL << 21, 0x80000000); 205 206 pr_info("IOBMAP L2 allocated at: %p\n", iob_l2_base); 207 208 /* Allocate a spare page to map all invalid IOTLB pages. */ 209 tmp = memblock_phys_alloc(IOBMAP_PAGE_SIZE, IOBMAP_PAGE_SIZE); 210 if (!tmp) 211 panic("IOBMAP: Cannot allocate spare page!"); 212 /* Empty l1 is marked invalid */ 213 iob_l1_emptyval = 0; 214 /* Empty l2 is mapped to dummy page */ 215 iob_l2_emptyval = IOBMAP_L2E_V | (tmp >> IOBMAP_PAGE_SHIFT); 216 217 iob = ioremap(IOB_BASE, IOB_SIZE); 218 if (!iob) 219 panic("IOBMAP: Cannot map registers!"); 220 221 /* setup direct mapping of the L1 entries */ 222 for (i = 0; i < 64; i++) { 223 /* Each L1 covers 32MB, i.e. 8K entries = 32K of ram */ 224 regword = IOBMAP_L1E_V | (__pa(iob_l2_base + i*0x2000) >> 12); 225 out_le32(iob+IOB_XLT_L1_REGBASE+i*4, regword); 226 } 227 228 /* set 2GB translation window, based at 0 */ 229 regword = in_le32(iob+IOB_AD_REG); 230 regword &= ~IOB_AD_TRNG_MASK; 231 regword |= IOB_AD_TRNG_2G; 232 out_le32(iob+IOB_AD_REG, regword); 233 234 /* Enable translation */ 235 regword = in_le32(iob+IOBCOM_REG); 236 regword |= IOBCOM_ATEN; 237 out_le32(iob+IOBCOM_REG, regword); 238 239 pr_debug(" <- %s\n", __func__); 240 241 return 0; 242 } 243 244 245 /* These are called very early. */ 246 void __init iommu_init_early_pasemi(void) 247 { 248 int iommu_off; 249 250 #ifndef CONFIG_PPC_PASEMI_IOMMU 251 iommu_off = 1; 252 #else 253 iommu_off = of_chosen && 254 of_get_property(of_chosen, "linux,iommu-off", NULL); 255 #endif 256 if (iommu_off) 257 return; 258 259 iob_init(NULL); 260 261 pasemi_pci_controller_ops.dma_dev_setup = pci_dma_dev_setup_pasemi; 262 pasemi_pci_controller_ops.dma_bus_setup = pci_dma_bus_setup_pasemi; 263 set_pci_dma_ops(&dma_iommu_ops); 264 } 265