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 #include "mm_32.h" 29 30 /* #define IOUNIT_DEBUG */ 31 #ifdef IOUNIT_DEBUG 32 #define IOD(x) printk(x) 33 #else 34 #define IOD(x) do { } while (0) 35 #endif 36 37 #define IOPERM (IOUPTE_CACHE | IOUPTE_WRITE | IOUPTE_VALID) 38 #define MKIOPTE(phys) __iopte((((phys)>>4) & IOUPTE_PAGE) | IOPERM) 39 40 static void __init iounit_iommu_init(struct platform_device *op) 41 { 42 struct iounit_struct *iounit; 43 iopte_t __iomem *xpt; 44 iopte_t __iomem *xptend; 45 46 iounit = kzalloc(sizeof(struct iounit_struct), GFP_ATOMIC); 47 if (!iounit) { 48 prom_printf("SUN4D: Cannot alloc iounit, halting.\n"); 49 prom_halt(); 50 } 51 52 iounit->limit[0] = IOUNIT_BMAP1_START; 53 iounit->limit[1] = IOUNIT_BMAP2_START; 54 iounit->limit[2] = IOUNIT_BMAPM_START; 55 iounit->limit[3] = IOUNIT_BMAPM_END; 56 iounit->rotor[1] = IOUNIT_BMAP2_START; 57 iounit->rotor[2] = IOUNIT_BMAPM_START; 58 59 xpt = of_ioremap(&op->resource[2], 0, PAGE_SIZE * 16, "XPT"); 60 if (!xpt) { 61 prom_printf("SUN4D: Cannot map External Page Table."); 62 prom_halt(); 63 } 64 65 op->dev.archdata.iommu = iounit; 66 iounit->page_table = xpt; 67 spin_lock_init(&iounit->lock); 68 69 xptend = iounit->page_table + (16 * PAGE_SIZE) / sizeof(iopte_t); 70 for (; xpt < xptend; xpt++) 71 sbus_writel(0, xpt); 72 } 73 74 static int __init iounit_init(void) 75 { 76 extern void sun4d_init_sbi_irq(void); 77 struct device_node *dp; 78 79 for_each_node_by_name(dp, "sbi") { 80 struct platform_device *op = of_find_device_by_node(dp); 81 82 iounit_iommu_init(op); 83 of_propagate_archdata(op); 84 } 85 86 sun4d_init_sbi_irq(); 87 88 return 0; 89 } 90 91 subsys_initcall(iounit_init); 92 93 /* One has to hold iounit->lock to call this */ 94 static unsigned long iounit_get_area(struct iounit_struct *iounit, unsigned long vaddr, int size) 95 { 96 int i, j, k, npages; 97 unsigned long rotor, scan, limit; 98 iopte_t iopte; 99 100 npages = ((vaddr & ~PAGE_MASK) + size + (PAGE_SIZE-1)) >> PAGE_SHIFT; 101 102 /* A tiny bit of magic ingredience :) */ 103 switch (npages) { 104 case 1: i = 0x0231; break; 105 case 2: i = 0x0132; break; 106 default: i = 0x0213; break; 107 } 108 109 IOD(("iounit_get_area(%08lx,%d[%d])=", vaddr, size, npages)); 110 111 next: j = (i & 15); 112 rotor = iounit->rotor[j - 1]; 113 limit = iounit->limit[j]; 114 scan = rotor; 115 nexti: scan = find_next_zero_bit(iounit->bmap, limit, scan); 116 if (scan + npages > limit) { 117 if (limit != rotor) { 118 limit = rotor; 119 scan = iounit->limit[j - 1]; 120 goto nexti; 121 } 122 i >>= 4; 123 if (!(i & 15)) 124 panic("iounit_get_area: Couldn't find free iopte slots for (%08lx,%d)\n", vaddr, size); 125 goto next; 126 } 127 for (k = 1, scan++; k < npages; k++) 128 if (test_bit(scan++, iounit->bmap)) 129 goto nexti; 130 iounit->rotor[j - 1] = (scan < limit) ? scan : iounit->limit[j - 1]; 131 scan -= npages; 132 iopte = MKIOPTE(__pa(vaddr & PAGE_MASK)); 133 vaddr = IOUNIT_DMA_BASE + (scan << PAGE_SHIFT) + (vaddr & ~PAGE_MASK); 134 for (k = 0; k < npages; k++, iopte = __iopte(iopte_val(iopte) + 0x100), scan++) { 135 set_bit(scan, iounit->bmap); 136 sbus_writel(iopte, &iounit->page_table[scan]); 137 } 138 IOD(("%08lx\n", vaddr)); 139 return vaddr; 140 } 141 142 static __u32 iounit_get_scsi_one(struct device *dev, char *vaddr, unsigned long len) 143 { 144 struct iounit_struct *iounit = dev->archdata.iommu; 145 unsigned long ret, flags; 146 147 spin_lock_irqsave(&iounit->lock, flags); 148 ret = iounit_get_area(iounit, (unsigned long)vaddr, len); 149 spin_unlock_irqrestore(&iounit->lock, flags); 150 return ret; 151 } 152 153 static void iounit_get_scsi_sgl(struct device *dev, struct scatterlist *sg, int sz) 154 { 155 struct iounit_struct *iounit = dev->archdata.iommu; 156 unsigned long flags; 157 158 /* FIXME: Cache some resolved pages - often several sg entries are to the same page */ 159 spin_lock_irqsave(&iounit->lock, flags); 160 while (sz != 0) { 161 --sz; 162 sg->dma_address = iounit_get_area(iounit, (unsigned long) sg_virt(sg), sg->length); 163 sg->dma_length = sg->length; 164 sg = sg_next(sg); 165 } 166 spin_unlock_irqrestore(&iounit->lock, flags); 167 } 168 169 static void iounit_release_scsi_one(struct device *dev, __u32 vaddr, unsigned long len) 170 { 171 struct iounit_struct *iounit = dev->archdata.iommu; 172 unsigned long flags; 173 174 spin_lock_irqsave(&iounit->lock, flags); 175 len = ((vaddr & ~PAGE_MASK) + len + (PAGE_SIZE-1)) >> PAGE_SHIFT; 176 vaddr = (vaddr - IOUNIT_DMA_BASE) >> PAGE_SHIFT; 177 IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr)); 178 for (len += vaddr; vaddr < len; vaddr++) 179 clear_bit(vaddr, iounit->bmap); 180 spin_unlock_irqrestore(&iounit->lock, flags); 181 } 182 183 static void iounit_release_scsi_sgl(struct device *dev, struct scatterlist *sg, int sz) 184 { 185 struct iounit_struct *iounit = dev->archdata.iommu; 186 unsigned long flags; 187 unsigned long vaddr, len; 188 189 spin_lock_irqsave(&iounit->lock, flags); 190 while (sz != 0) { 191 --sz; 192 len = ((sg->dma_address & ~PAGE_MASK) + sg->length + (PAGE_SIZE-1)) >> PAGE_SHIFT; 193 vaddr = (sg->dma_address - IOUNIT_DMA_BASE) >> PAGE_SHIFT; 194 IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr)); 195 for (len += vaddr; vaddr < len; vaddr++) 196 clear_bit(vaddr, iounit->bmap); 197 sg = sg_next(sg); 198 } 199 spin_unlock_irqrestore(&iounit->lock, flags); 200 } 201 202 #ifdef CONFIG_SBUS 203 static int iounit_map_dma_area(struct device *dev, dma_addr_t *pba, unsigned long va, unsigned long addr, int len) 204 { 205 struct iounit_struct *iounit = dev->archdata.iommu; 206 unsigned long page, end; 207 pgprot_t dvma_prot; 208 iopte_t __iomem *iopte; 209 210 *pba = addr; 211 212 dvma_prot = __pgprot(SRMMU_CACHE | SRMMU_ET_PTE | SRMMU_PRIV); 213 end = PAGE_ALIGN((addr + len)); 214 while(addr < end) { 215 page = va; 216 { 217 pgd_t *pgdp; 218 pmd_t *pmdp; 219 pte_t *ptep; 220 long i; 221 222 pgdp = pgd_offset(&init_mm, addr); 223 pmdp = pmd_offset(pgdp, addr); 224 ptep = pte_offset_map(pmdp, addr); 225 226 set_pte(ptep, mk_pte(virt_to_page(page), dvma_prot)); 227 228 i = ((addr - IOUNIT_DMA_BASE) >> PAGE_SHIFT); 229 230 iopte = iounit->page_table + i; 231 sbus_writel(MKIOPTE(__pa(page)), iopte); 232 } 233 addr += PAGE_SIZE; 234 va += PAGE_SIZE; 235 } 236 flush_cache_all(); 237 flush_tlb_all(); 238 239 return 0; 240 } 241 242 static void iounit_unmap_dma_area(struct device *dev, unsigned long addr, int len) 243 { 244 /* XXX Somebody please fill this in */ 245 } 246 #endif 247 248 static const struct sparc32_dma_ops iounit_dma_ops = { 249 .get_scsi_one = iounit_get_scsi_one, 250 .get_scsi_sgl = iounit_get_scsi_sgl, 251 .release_scsi_one = iounit_release_scsi_one, 252 .release_scsi_sgl = iounit_release_scsi_sgl, 253 #ifdef CONFIG_SBUS 254 .map_dma_area = iounit_map_dma_area, 255 .unmap_dma_area = iounit_unmap_dma_area, 256 #endif 257 }; 258 259 void __init ld_mmu_iounit(void) 260 { 261 sparc32_dma_ops = &iounit_dma_ops; 262 } 263