arch/sparc/mm/io-unit.c

   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
  16 #include <asm/pgalloc.h>
  17 #include <asm/pgtable.h>
  18 #include <asm/sbus.h>
  19 #include <asm/io.h>
  20 #include <asm/io-unit.h>
  21 #include <asm/mxcc.h>
  22 #include <asm/cacheflush.h>
  23 #include <asm/tlbflush.h>
  24 #include <asm/dma.h>
  25 #include <asm/oplib.h>
  26
  27 /* #define IOUNIT_DEBUG */
  28 #ifdef IOUNIT_DEBUG
  29 #define IOD(x) printk(x)
  30 #else
  31 #define IOD(x) do { } while (0)
  32 #endif
  33
  34 #define IOPERM        (IOUPTE_CACHE | IOUPTE_WRITE | IOUPTE_VALID)
  35 #define MKIOPTE(phys) __iopte((((phys)>>4) & IOUPTE_PAGE) | IOPERM)
  36
  37 void __init
  38 iounit_init(int sbi_node, int io_node, struct sbus_bus *sbus)
  39 {
  40         iopte_t *xpt, *xptend;
  41         struct iounit_struct *iounit;
  42         struct linux_prom_registers iommu_promregs[PROMREG_MAX];
  43         struct resource r;
  44
  45         iounit = kzalloc(sizeof(struct iounit_struct), GFP_ATOMIC);
  46         if (!iounit) {
  47                 prom_printf("SUN4D: Cannot alloc iounit, halting.\n");
  48                 prom_halt();
  49         }
  50
  51         iounit->limit[0] = IOUNIT_BMAP1_START;
  52         iounit->limit[1] = IOUNIT_BMAP2_START;
  53         iounit->limit[2] = IOUNIT_BMAPM_START;
  54         iounit->limit[3] = IOUNIT_BMAPM_END;
  55         iounit->rotor[1] = IOUNIT_BMAP2_START;
  56         iounit->rotor[2] = IOUNIT_BMAPM_START;
  57
  58         xpt = NULL;
  59         if(prom_getproperty(sbi_node, "reg", (void *) iommu_promregs,
  60                             sizeof(iommu_promregs)) != -1) {
  61                 prom_apply_generic_ranges(io_node, 0, iommu_promregs, 3);
  62                 memset(&r, 0, sizeof(r));
  63                 r.flags = iommu_promregs[2].which_io;
  64                 r.start = iommu_promregs[2].phys_addr;
  65                 xpt = (iopte_t *) sbus_ioremap(&r, 0, PAGE_SIZE * 16, "XPT");
  66         }
  67         if(!xpt) panic("Cannot map External Page Table.");
  68
  69         sbus->ofdev.dev.archdata.iommu = iounit;
  70         iounit->page_table = xpt;
  71         spin_lock_init(&iounit->lock);
  72
  73         for (xptend = iounit->page_table + (16 * PAGE_SIZE) / sizeof(iopte_t);
  74              xpt < xptend;)
  75                 iopte_val(*xpt++) = 0;
  76 }
  77
  78 /* One has to hold iounit->lock to call this */
  79 static unsigned long iounit_get_area(struct iounit_struct *iounit, unsigned long vaddr, int size)
  80 {
  81         int i, j, k, npages;
  82         unsigned long rotor, scan, limit;
  83         iopte_t iopte;
  84
  85         npages = ((vaddr & ~PAGE_MASK) + size + (PAGE_SIZE-1)) >> PAGE_SHIFT;
  86
  87         /* A tiny bit of magic ingredience :) */
  88         switch (npages) {
  89         case 1: i = 0x0231; break;
  90         case 2: i = 0x0132; break;
  91         default: i = 0x0213; break;
  92         }
  93
  94         IOD(("iounit_get_area(%08lx,%d[%d])=", vaddr, size, npages));
  95
  96 next:   j = (i & 15);
  97         rotor = iounit->rotor[j - 1];
  98         limit = iounit->limit[j];
  99         scan = rotor;
 100 nexti:  scan = find_next_zero_bit(iounit->bmap, limit, scan);
 101         if (scan + npages > limit) {
 102                 if (limit != rotor) {
 103                         limit = rotor;
 104                         scan = iounit->limit[j - 1];
 105                         goto nexti;
 106                 }
 107                 i >>= 4;
 108                 if (!(i & 15))
 109                         panic("iounit_get_area: Couldn't find free iopte slots for (%08lx,%d)\n", vaddr, size);
 110                 goto next;
 111         }
 112         for (k = 1, scan++; k < npages; k++)
 113                 if (test_bit(scan++, iounit->bmap))
 114                         goto nexti;
 115         iounit->rotor[j - 1] = (scan < limit) ? scan : iounit->limit[j - 1];
 116         scan -= npages;
 117         iopte = MKIOPTE(__pa(vaddr & PAGE_MASK));
 118         vaddr = IOUNIT_DMA_BASE + (scan << PAGE_SHIFT) + (vaddr & ~PAGE_MASK);
 119         for (k = 0; k < npages; k++, iopte = __iopte(iopte_val(iopte) + 0x100), scan++) {
 120                 set_bit(scan, iounit->bmap);
 121                 iounit->page_table[scan] = iopte;
 122         }
 123         IOD(("%08lx\n", vaddr));
 124         return vaddr;
 125 }
 126
 127 static __u32 iounit_get_scsi_one(char *vaddr, unsigned long len, struct sbus_bus *sbus)
 128 {
 129         unsigned long ret, flags;
 130         struct iounit_struct *iounit = sbus->ofdev.dev.archdata.iommu;
 131
 132         spin_lock_irqsave(&iounit->lock, flags);
 133         ret = iounit_get_area(iounit, (unsigned long)vaddr, len);
 134         spin_unlock_irqrestore(&iounit->lock, flags);
 135         return ret;
 136 }
 137
 138 static void iounit_get_scsi_sgl(struct scatterlist *sg, int sz, struct sbus_bus *sbus)
 139 {
 140         unsigned long flags;
 141         struct iounit_struct *iounit = sbus->ofdev.dev.archdata.iommu;
 142
 143         /* FIXME: Cache some resolved pages - often several sg entries are to the same page */
 144         spin_lock_irqsave(&iounit->lock, flags);
 145         while (sz != 0) {
 146                 --sz;
 147                 sg->dvma_address = iounit_get_area(iounit, (unsigned long) sg_virt(sg), sg->length);
 148                 sg->dvma_length = sg->length;
 149                 sg = sg_next(sg);
 150         }
 151         spin_unlock_irqrestore(&iounit->lock, flags);
 152 }
 153
 154 static void iounit_release_scsi_one(__u32 vaddr, unsigned long len, struct sbus_bus *sbus)
 155 {
 156         unsigned long flags;
 157         struct iounit_struct *iounit = sbus->ofdev.dev.archdata.iommu;
 158
 159         spin_lock_irqsave(&iounit->lock, flags);
 160         len = ((vaddr & ~PAGE_MASK) + len + (PAGE_SIZE-1)) >> PAGE_SHIFT;
 161         vaddr = (vaddr - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
 162         IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr));
 163         for (len += vaddr; vaddr < len; vaddr++)
 164                 clear_bit(vaddr, iounit->bmap);
 165         spin_unlock_irqrestore(&iounit->lock, flags);
 166 }
 167
 168 static void iounit_release_scsi_sgl(struct scatterlist *sg, int sz, struct sbus_bus *sbus)
 169 {
 170         unsigned long flags;
 171         unsigned long vaddr, len;
 172         struct iounit_struct *iounit = sbus->ofdev.dev.archdata.iommu;
 173
 174         spin_lock_irqsave(&iounit->lock, flags);
 175         while (sz != 0) {
 176                 --sz;
 177                 len = ((sg->dvma_address & ~PAGE_MASK) + sg->length + (PAGE_SIZE-1)) >> PAGE_SHIFT;
 178                 vaddr = (sg->dvma_address - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
 179                 IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr));
 180                 for (len += vaddr; vaddr < len; vaddr++)
 181                         clear_bit(vaddr, iounit->bmap);
 182                 sg = sg_next(sg);
 183         }
 184         spin_unlock_irqrestore(&iounit->lock, flags);
 185 }
 186
 187 #ifdef CONFIG_SBUS
 188 static int iounit_map_dma_area(dma_addr_t *pba, unsigned long va, __u32 addr, int len)
 189 {
 190         unsigned long page, end;
 191         pgprot_t dvma_prot;
 192         iopte_t *iopte;
 193         struct sbus_bus *sbus;
 194
 195         *pba = addr;
 196
 197         dvma_prot = __pgprot(SRMMU_CACHE | SRMMU_ET_PTE | SRMMU_PRIV);
 198         end = PAGE_ALIGN((addr + len));
 199         while(addr < end) {
 200                 page = va;
 201                 {
 202                         pgd_t *pgdp;
 203                         pmd_t *pmdp;
 204                         pte_t *ptep;
 205                         long i;
 206
 207                         pgdp = pgd_offset(&init_mm, addr);
 208                         pmdp = pmd_offset(pgdp, addr);
 209                         ptep = pte_offset_map(pmdp, addr);
 210
 211                         set_pte(ptep, mk_pte(virt_to_page(page), dvma_prot));
 212
 213                         i = ((addr - IOUNIT_DMA_BASE) >> PAGE_SHIFT);
 214
 215                         for_each_sbus(sbus) {
 216                                 struct iounit_struct *iounit = sbus->ofdev.dev.archdata.iommu;
 217
 218                                 iopte = (iopte_t *)(iounit->page_table + i);
 219                                 *iopte = MKIOPTE(__pa(page));
 220                         }
 221                 }
 222                 addr += PAGE_SIZE;
 223                 va += PAGE_SIZE;
 224         }
 225         flush_cache_all();
 226         flush_tlb_all();
 227
 228         return 0;
 229 }
 230
 231 static void iounit_unmap_dma_area(unsigned long addr, int len)
 232 {
 233         /* XXX Somebody please fill this in */
 234 }
 235
 236 /* XXX We do not pass sbus device here, bad. */
 237 static struct page *iounit_translate_dvma(unsigned long addr)
 238 {
 239         struct sbus_bus *sbus = sbus_root;      /* They are all the same */
 240         struct iounit_struct *iounit = sbus->ofdev.dev.archdata.iommu;
 241         int i;
 242         iopte_t *iopte;
 243
 244         i = ((addr - IOUNIT_DMA_BASE) >> PAGE_SHIFT);
 245         iopte = (iopte_t *)(iounit->page_table + i);
 246         return pfn_to_page(iopte_val(*iopte) >> (PAGE_SHIFT-4)); /* XXX sun4d guru, help */
 247 }
 248 #endif
 249
 250 static char *iounit_lockarea(char *vaddr, unsigned long len)
 251 {
 252 /* FIXME: Write this */
 253         return vaddr;
 254 }
 255
 256 static void iounit_unlockarea(char *vaddr, unsigned long len)
 257 {
 258 /* FIXME: Write this */
 259 }
 260
 261 void __init ld_mmu_iounit(void)
 262 {
 263         BTFIXUPSET_CALL(mmu_lockarea, iounit_lockarea, BTFIXUPCALL_RETO0);
 264         BTFIXUPSET_CALL(mmu_unlockarea, iounit_unlockarea, BTFIXUPCALL_NOP);
 265
 266         BTFIXUPSET_CALL(mmu_get_scsi_one, iounit_get_scsi_one, BTFIXUPCALL_NORM);
 267         BTFIXUPSET_CALL(mmu_get_scsi_sgl, iounit_get_scsi_sgl, BTFIXUPCALL_NORM);
 268         BTFIXUPSET_CALL(mmu_release_scsi_one, iounit_release_scsi_one, BTFIXUPCALL_NORM);
 269         BTFIXUPSET_CALL(mmu_release_scsi_sgl, iounit_release_scsi_sgl, BTFIXUPCALL_NORM);
 270
 271 #ifdef CONFIG_SBUS
 272         BTFIXUPSET_CALL(mmu_map_dma_area, iounit_map_dma_area, BTFIXUPCALL_NORM);
 273         BTFIXUPSET_CALL(mmu_unmap_dma_area, iounit_unmap_dma_area, BTFIXUPCALL_NORM);
 274         BTFIXUPSET_CALL(mmu_translate_dvma, iounit_translate_dvma, BTFIXUPCALL_NORM);
 275 #endif
 276 }
 277
 278 __u32 iounit_map_dma_init(struct sbus_bus *sbus, int size)
 279 {
 280         int i, j, k, npages;
 281         unsigned long rotor, scan, limit;
 282         unsigned long flags;
 283         __u32 ret;
 284         struct iounit_struct *iounit = sbus->ofdev.dev.archdata.iommu;
 285
 286         npages = (size + (PAGE_SIZE-1)) >> PAGE_SHIFT;
 287         i = 0x0213;
 288         spin_lock_irqsave(&iounit->lock, flags);
 289 next:   j = (i & 15);
 290         rotor = iounit->rotor[j - 1];
 291         limit = iounit->limit[j];
 292         scan = rotor;
 293 nexti:  scan = find_next_zero_bit(iounit->bmap, limit, scan);
 294         if (scan + npages > limit) {
 295                 if (limit != rotor) {
 296                         limit = rotor;
 297                         scan = iounit->limit[j - 1];
 298                         goto nexti;
 299                 }
 300                 i >>= 4;
 301                 if (!(i & 15))
 302                         panic("iounit_map_dma_init: Couldn't find free iopte slots for %d bytes\n", size);
 303                 goto next;
 304         }
 305         for (k = 1, scan++; k < npages; k++)
 306                 if (test_bit(scan++, iounit->bmap))
 307                         goto nexti;
 308         iounit->rotor[j - 1] = (scan < limit) ? scan : iounit->limit[j - 1];
 309         scan -= npages;
 310         ret = IOUNIT_DMA_BASE + (scan << PAGE_SHIFT);
 311         for (k = 0; k < npages; k++, scan++)
 312                 set_bit(scan, iounit->bmap);
 313         spin_unlock_irqrestore(&iounit->lock, flags);
 314         return ret;
 315 }
 316
 317 __u32 iounit_map_dma_page(__u32 vaddr, void *addr, struct sbus_bus *sbus)
 318 {
 319         int scan = (vaddr - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
 320         struct iounit_struct *iounit = sbus->ofdev.dev.archdata.iommu;
 321
 322         iounit->page_table[scan] = MKIOPTE(__pa(((unsigned long)addr) & PAGE_MASK));
 323         return vaddr + (((unsigned long)addr) & ~PAGE_MASK);
 324 }