1 /* 2 * io-unit.c: IO-UNIT specific routines for memory management. 3 * 4 * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz) 5 */ 6 7 #include <linux/kernel.h> 8 #include <linux/init.h> 9 #include <linux/slab.h> 10 #include <linux/spinlock.h> 11 #include <linux/mm.h> 12 #include <linux/highmem.h> /* pte_offset_map => kmap_atomic */ 13 #include <linux/bitops.h> 14 #include <linux/scatterlist.h> 15 #include <linux/of.h> 16 #include <linux/of_device.h> 17 18 #include <asm/pgalloc.h> 19 #include <asm/pgtable.h> 20 #include <asm/io.h> 21 #include <asm/io-unit.h> 22 #include <asm/mxcc.h> 23 #include <asm/cacheflush.h> 24 #include <asm/tlbflush.h> 25 #include <asm/dma.h> 26 #include <asm/oplib.h> 27 28 /* #define IOUNIT_DEBUG */ 29 #ifdef IOUNIT_DEBUG 30 #define IOD(x) printk(x) 31 #else 32 #define IOD(x) do { } while (0) 33 #endif 34 35 #define IOPERM (IOUPTE_CACHE | IOUPTE_WRITE | IOUPTE_VALID) 36 #define MKIOPTE(phys) __iopte((((phys)>>4) & IOUPTE_PAGE) | IOPERM) 37 38 static void __init iounit_iommu_init(struct platform_device *op) 39 { 40 struct iounit_struct *iounit; 41 iopte_t *xpt, *xptend; 42 43 iounit = kzalloc(sizeof(struct iounit_struct), GFP_ATOMIC); 44 if (!iounit) { 45 prom_printf("SUN4D: Cannot alloc iounit, halting.\n"); 46 prom_halt(); 47 } 48 49 iounit->limit[0] = IOUNIT_BMAP1_START; 50 iounit->limit[1] = IOUNIT_BMAP2_START; 51 iounit->limit[2] = IOUNIT_BMAPM_START; 52 iounit->limit[3] = IOUNIT_BMAPM_END; 53 iounit->rotor[1] = IOUNIT_BMAP2_START; 54 iounit->rotor[2] = IOUNIT_BMAPM_START; 55 56 xpt = of_ioremap(&op->resource[2], 0, PAGE_SIZE * 16, "XPT"); 57 if (!xpt) { 58 prom_printf("SUN4D: Cannot map External Page Table."); 59 prom_halt(); 60 } 61 62 op->dev.archdata.iommu = iounit; 63 iounit->page_table = xpt; 64 spin_lock_init(&iounit->lock); 65 66 for (xptend = iounit->page_table + (16 * PAGE_SIZE) / sizeof(iopte_t); 67 xpt < xptend;) 68 iopte_val(*xpt++) = 0; 69 } 70 71 static int __init iounit_init(void) 72 { 73 extern void sun4d_init_sbi_irq(void); 74 struct device_node *dp; 75 76 for_each_node_by_name(dp, "sbi") { 77 struct platform_device *op = of_find_device_by_node(dp); 78 79 iounit_iommu_init(op); 80 of_propagate_archdata(op); 81 } 82 83 sun4d_init_sbi_irq(); 84 85 return 0; 86 } 87 88 subsys_initcall(iounit_init); 89 90 /* One has to hold iounit->lock to call this */ 91 static unsigned long iounit_get_area(struct iounit_struct *iounit, unsigned long vaddr, int size) 92 { 93 int i, j, k, npages; 94 unsigned long rotor, scan, limit; 95 iopte_t iopte; 96 97 npages = ((vaddr & ~PAGE_MASK) + size + (PAGE_SIZE-1)) >> PAGE_SHIFT; 98 99 /* A tiny bit of magic ingredience :) */ 100 switch (npages) { 101 case 1: i = 0x0231; break; 102 case 2: i = 0x0132; break; 103 default: i = 0x0213; break; 104 } 105 106 IOD(("iounit_get_area(%08lx,%d[%d])=", vaddr, size, npages)); 107 108 next: j = (i & 15); 109 rotor = iounit->rotor[j - 1]; 110 limit = iounit->limit[j]; 111 scan = rotor; 112 nexti: scan = find_next_zero_bit(iounit->bmap, limit, scan); 113 if (scan + npages > limit) { 114 if (limit != rotor) { 115 limit = rotor; 116 scan = iounit->limit[j - 1]; 117 goto nexti; 118 } 119 i >>= 4; 120 if (!(i & 15)) 121 panic("iounit_get_area: Couldn't find free iopte slots for (%08lx,%d)\n", vaddr, size); 122 goto next; 123 } 124 for (k = 1, scan++; k < npages; k++) 125 if (test_bit(scan++, iounit->bmap)) 126 goto nexti; 127 iounit->rotor[j - 1] = (scan < limit) ? scan : iounit->limit[j - 1]; 128 scan -= npages; 129 iopte = MKIOPTE(__pa(vaddr & PAGE_MASK)); 130 vaddr = IOUNIT_DMA_BASE + (scan << PAGE_SHIFT) + (vaddr & ~PAGE_MASK); 131 for (k = 0; k < npages; k++, iopte = __iopte(iopte_val(iopte) + 0x100), scan++) { 132 set_bit(scan, iounit->bmap); 133 iounit->page_table[scan] = iopte; 134 } 135 IOD(("%08lx\n", vaddr)); 136 return vaddr; 137 } 138 139 static __u32 iounit_get_scsi_one(struct device *dev, char *vaddr, unsigned long len) 140 { 141 struct iounit_struct *iounit = dev->archdata.iommu; 142 unsigned long ret, flags; 143 144 spin_lock_irqsave(&iounit->lock, flags); 145 ret = iounit_get_area(iounit, (unsigned long)vaddr, len); 146 spin_unlock_irqrestore(&iounit->lock, flags); 147 return ret; 148 } 149 150 static void iounit_get_scsi_sgl(struct device *dev, struct scatterlist *sg, int sz) 151 { 152 struct iounit_struct *iounit = dev->archdata.iommu; 153 unsigned long flags; 154 155 /* FIXME: Cache some resolved pages - often several sg entries are to the same page */ 156 spin_lock_irqsave(&iounit->lock, flags); 157 while (sz != 0) { 158 --sz; 159 sg->dma_address = iounit_get_area(iounit, (unsigned long) sg_virt(sg), sg->length); 160 sg->dma_length = sg->length; 161 sg = sg_next(sg); 162 } 163 spin_unlock_irqrestore(&iounit->lock, flags); 164 } 165 166 static void iounit_release_scsi_one(struct device *dev, __u32 vaddr, unsigned long len) 167 { 168 struct iounit_struct *iounit = dev->archdata.iommu; 169 unsigned long flags; 170 171 spin_lock_irqsave(&iounit->lock, flags); 172 len = ((vaddr & ~PAGE_MASK) + len + (PAGE_SIZE-1)) >> PAGE_SHIFT; 173 vaddr = (vaddr - IOUNIT_DMA_BASE) >> PAGE_SHIFT; 174 IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr)); 175 for (len += vaddr; vaddr < len; vaddr++) 176 clear_bit(vaddr, iounit->bmap); 177 spin_unlock_irqrestore(&iounit->lock, flags); 178 } 179 180 static void iounit_release_scsi_sgl(struct device *dev, struct scatterlist *sg, int sz) 181 { 182 struct iounit_struct *iounit = dev->archdata.iommu; 183 unsigned long flags; 184 unsigned long vaddr, len; 185 186 spin_lock_irqsave(&iounit->lock, flags); 187 while (sz != 0) { 188 --sz; 189 len = ((sg->dma_address & ~PAGE_MASK) + sg->length + (PAGE_SIZE-1)) >> PAGE_SHIFT; 190 vaddr = (sg->dma_address - IOUNIT_DMA_BASE) >> PAGE_SHIFT; 191 IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr)); 192 for (len += vaddr; vaddr < len; vaddr++) 193 clear_bit(vaddr, iounit->bmap); 194 sg = sg_next(sg); 195 } 196 spin_unlock_irqrestore(&iounit->lock, flags); 197 } 198 199 #ifdef CONFIG_SBUS 200 static int iounit_map_dma_area(struct device *dev, dma_addr_t *pba, unsigned long va, unsigned long addr, int len) 201 { 202 struct iounit_struct *iounit = dev->archdata.iommu; 203 unsigned long page, end; 204 pgprot_t dvma_prot; 205 iopte_t *iopte; 206 207 *pba = addr; 208 209 dvma_prot = __pgprot(SRMMU_CACHE | SRMMU_ET_PTE | SRMMU_PRIV); 210 end = PAGE_ALIGN((addr + len)); 211 while(addr < end) { 212 page = va; 213 { 214 pgd_t *pgdp; 215 pmd_t *pmdp; 216 pte_t *ptep; 217 long i; 218 219 pgdp = pgd_offset(&init_mm, addr); 220 pmdp = pmd_offset(pgdp, addr); 221 ptep = pte_offset_map(pmdp, addr); 222 223 set_pte(ptep, mk_pte(virt_to_page(page), dvma_prot)); 224 225 i = ((addr - IOUNIT_DMA_BASE) >> PAGE_SHIFT); 226 227 iopte = (iopte_t *)(iounit->page_table + i); 228 *iopte = MKIOPTE(__pa(page)); 229 } 230 addr += PAGE_SIZE; 231 va += PAGE_SIZE; 232 } 233 flush_cache_all(); 234 flush_tlb_all(); 235 236 return 0; 237 } 238 239 static void iounit_unmap_dma_area(struct device *dev, unsigned long addr, int len) 240 { 241 /* XXX Somebody please fill this in */ 242 } 243 #endif 244 245 static const struct sparc32_dma_ops iounit_dma_ops = { 246 .get_scsi_one = iounit_get_scsi_one, 247 .get_scsi_sgl = iounit_get_scsi_sgl, 248 .release_scsi_one = iounit_release_scsi_one, 249 .release_scsi_sgl = iounit_release_scsi_sgl, 250 #ifdef CONFIG_SBUS 251 .map_dma_area = iounit_map_dma_area, 252 .unmap_dma_area = iounit_unmap_dma_area, 253 #endif 254 }; 255 256 void __init ld_mmu_iounit(void) 257 { 258 sparc32_dma_ops = &iounit_dma_ops; 259 } 260