arch/sparc/mm/io-unit.c

   1 /* $Id: io-unit.c,v 1.24 2001/12/17 07:05:09 davem Exp $
   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/config.h>
   8 #include <linux/kernel.h>
   9 #include <linux/init.h>
  10 #include <linux/slab.h>
  11 #include <linux/spinlock.h>
  12 #include <linux/mm.h>
  13 #include <linux/highmem.h>      /* pte_offset_map => kmap_atomic */
  14 #include <linux/bitops.h>
  15
  16 #include <asm/scatterlist.h>
  17 #include <asm/pgalloc.h>
  18 #include <asm/pgtable.h>
  19 #include <asm/sbus.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
  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 = kmalloc(sizeof(struct iounit_struct), GFP_ATOMIC);
  46
  47         memset(iounit, 0, sizeof(*iounit));
  48         iounit->limit[0] = IOUNIT_BMAP1_START;
  49         iounit->limit[1] = IOUNIT_BMAP2_START;
  50         iounit->limit[2] = IOUNIT_BMAPM_START;
  51         iounit->limit[3] = IOUNIT_BMAPM_END;
  52         iounit->rotor[1] = IOUNIT_BMAP2_START;
  53         iounit->rotor[2] = IOUNIT_BMAPM_START;
  54
  55         xpt = NULL;
  56         if(prom_getproperty(sbi_node, "reg", (void *) iommu_promregs,
  57                             sizeof(iommu_promregs)) != -1) {
  58                 prom_apply_generic_ranges(io_node, 0, iommu_promregs, 3);
  59                 memset(&r, 0, sizeof(r));
  60                 r.flags = iommu_promregs[2].which_io;
  61                 r.start = iommu_promregs[2].phys_addr;
  62                 xpt = (iopte_t *) sbus_ioremap(&r, 0, PAGE_SIZE * 16, "XPT");
  63         }
  64         if(!xpt) panic("Cannot map External Page Table.");
  65
  66         sbus->iommu = (struct iommu_struct *)iounit;
  67         iounit->page_table = xpt;
  68
  69         for (xptend = iounit->page_table + (16 * PAGE_SIZE) / sizeof(iopte_t);
  70              xpt < xptend;)
  71                 iopte_val(*xpt++) = 0;
  72 }
  73
  74 /* One has to hold iounit->lock to call this */
  75 static unsigned long iounit_get_area(struct iounit_struct *iounit, unsigned long vaddr, int size)
  76 {
  77         int i, j, k, npages;
  78         unsigned long rotor, scan, limit;
  79         iopte_t iopte;
  80
  81         npages = ((vaddr & ~PAGE_MASK) + size + (PAGE_SIZE-1)) >> PAGE_SHIFT;
  82
  83         /* A tiny bit of magic ingredience :) */
  84         switch (npages) {
  85         case 1: i = 0x0231; break;
  86         case 2: i = 0x0132; break;
  87         default: i = 0x0213; break;
  88         }
  89
  90         IOD(("iounit_get_area(%08lx,%d[%d])=", vaddr, size, npages));
  91
  92 next:   j = (i & 15);
  93         rotor = iounit->rotor[j - 1];
  94         limit = iounit->limit[j];
  95         scan = rotor;
  96 nexti:  scan = find_next_zero_bit(iounit->bmap, limit, scan);
  97         if (scan + npages > limit) {
  98                 if (limit != rotor) {
  99                         limit = rotor;
 100                         scan = iounit->limit[j - 1];
 101                         goto nexti;
 102                 }
 103                 i >>= 4;
 104                 if (!(i & 15))
 105                         panic("iounit_get_area: Couldn't find free iopte slots for (%08lx,%d)\n", vaddr, size);
 106                 goto next;
 107         }
 108         for (k = 1, scan++; k < npages; k++)
 109                 if (test_bit(scan++, iounit->bmap))
 110                         goto nexti;
 111         iounit->rotor[j - 1] = (scan < limit) ? scan : iounit->limit[j - 1];
 112         scan -= npages;
 113         iopte = MKIOPTE(__pa(vaddr & PAGE_MASK));
 114         vaddr = IOUNIT_DMA_BASE + (scan << PAGE_SHIFT) + (vaddr & ~PAGE_MASK);
 115         for (k = 0; k < npages; k++, iopte = __iopte(iopte_val(iopte) + 0x100), scan++) {
 116                 set_bit(scan, iounit->bmap);
 117                 iounit->page_table[scan] = iopte;
 118         }
 119         IOD(("%08lx\n", vaddr));
 120         return vaddr;
 121 }
 122
 123 static __u32 iounit_get_scsi_one(char *vaddr, unsigned long len, struct sbus_bus *sbus)
 124 {
 125         unsigned long ret, flags;
 126         struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
 127
 128         spin_lock_irqsave(&iounit->lock, flags);
 129         ret = iounit_get_area(iounit, (unsigned long)vaddr, len);
 130         spin_unlock_irqrestore(&iounit->lock, flags);
 131         return ret;
 132 }
 133
 134 static void iounit_get_scsi_sgl(struct scatterlist *sg, int sz, struct sbus_bus *sbus)
 135 {
 136         unsigned long flags;
 137         struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
 138
 139         /* FIXME: Cache some resolved pages - often several sg entries are to the same page */
 140         spin_lock_irqsave(&iounit->lock, flags);
 141         while (sz != 0) {
 142                 --sz;
 143                 sg[sz].dvma_address = iounit_get_area(iounit, (unsigned long)page_address(sg[sz].page) + sg[sz].offset, sg[sz].length);
 144                 sg[sz].dvma_length = sg[sz].length;
 145         }
 146         spin_unlock_irqrestore(&iounit->lock, flags);
 147 }
 148
 149 static void iounit_release_scsi_one(__u32 vaddr, unsigned long len, struct sbus_bus *sbus)
 150 {
 151         unsigned long flags;
 152         struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
 153
 154         spin_lock_irqsave(&iounit->lock, flags);
 155         len = ((vaddr & ~PAGE_MASK) + len + (PAGE_SIZE-1)) >> PAGE_SHIFT;
 156         vaddr = (vaddr - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
 157         IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr));
 158         for (len += vaddr; vaddr < len; vaddr++)
 159                 clear_bit(vaddr, iounit->bmap);
 160         spin_unlock_irqrestore(&iounit->lock, flags);
 161 }
 162
 163 static void iounit_release_scsi_sgl(struct scatterlist *sg, int sz, struct sbus_bus *sbus)
 164 {
 165         unsigned long flags;
 166         unsigned long vaddr, len;
 167         struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
 168
 169         spin_lock_irqsave(&iounit->lock, flags);
 170         while (sz != 0) {
 171                 --sz;
 172                 len = ((sg[sz].dvma_address & ~PAGE_MASK) + sg[sz].length + (PAGE_SIZE-1)) >> PAGE_SHIFT;
 173                 vaddr = (sg[sz].dvma_address - 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         }
 178         spin_unlock_irqrestore(&iounit->lock, flags);
 179 }
 180
 181 #ifdef CONFIG_SBUS
 182 static int iounit_map_dma_area(dma_addr_t *pba, unsigned long va, __u32 addr, int len)
 183 {
 184         unsigned long page, end;
 185         pgprot_t dvma_prot;
 186         iopte_t *iopte;
 187         struct sbus_bus *sbus;
 188
 189         *pba = addr;
 190
 191         dvma_prot = __pgprot(SRMMU_CACHE | SRMMU_ET_PTE | SRMMU_PRIV);
 192         end = PAGE_ALIGN((addr + len));
 193         while(addr < end) {
 194                 page = va;
 195                 {
 196                         pgd_t *pgdp;
 197                         pmd_t *pmdp;
 198                         pte_t *ptep;
 199                         long i;
 200
 201                         pgdp = pgd_offset(&init_mm, addr);
 202                         pmdp = pmd_offset(pgdp, addr);
 203                         ptep = pte_offset_map(pmdp, addr);
 204
 205                         set_pte(ptep, mk_pte(virt_to_page(page), dvma_prot));
 206
 207                         i = ((addr - IOUNIT_DMA_BASE) >> PAGE_SHIFT);
 208
 209                         for_each_sbus(sbus) {
 210                                 struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
 211
 212                                 iopte = (iopte_t *)(iounit->page_table + i);
 213                                 *iopte = MKIOPTE(__pa(page));
 214                         }
 215                 }
 216                 addr += PAGE_SIZE;
 217                 va += PAGE_SIZE;
 218         }
 219         flush_cache_all();
 220         flush_tlb_all();
 221
 222         return 0;
 223 }
 224
 225 static void iounit_unmap_dma_area(unsigned long addr, int len)
 226 {
 227         /* XXX Somebody please fill this in */
 228 }
 229
 230 /* XXX We do not pass sbus device here, bad. */
 231 static struct page *iounit_translate_dvma(unsigned long addr)
 232 {
 233         struct sbus_bus *sbus = sbus_root;      /* They are all the same */
 234         struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
 235         int i;
 236         iopte_t *iopte;
 237
 238         i = ((addr - IOUNIT_DMA_BASE) >> PAGE_SHIFT);
 239         iopte = (iopte_t *)(iounit->page_table + i);
 240         return pfn_to_page(iopte_val(*iopte) >> (PAGE_SHIFT-4)); /* XXX sun4d guru, help */
 241 }
 242 #endif
 243
 244 static char *iounit_lockarea(char *vaddr, unsigned long len)
 245 {
 246 /* FIXME: Write this */
 247         return vaddr;
 248 }
 249
 250 static void iounit_unlockarea(char *vaddr, unsigned long len)
 251 {
 252 /* FIXME: Write this */
 253 }
 254
 255 void __init ld_mmu_iounit(void)
 256 {
 257         BTFIXUPSET_CALL(mmu_lockarea, iounit_lockarea, BTFIXUPCALL_RETO0);
 258         BTFIXUPSET_CALL(mmu_unlockarea, iounit_unlockarea, BTFIXUPCALL_NOP);
 259
 260         BTFIXUPSET_CALL(mmu_get_scsi_one, iounit_get_scsi_one, BTFIXUPCALL_NORM);
 261         BTFIXUPSET_CALL(mmu_get_scsi_sgl, iounit_get_scsi_sgl, BTFIXUPCALL_NORM);
 262         BTFIXUPSET_CALL(mmu_release_scsi_one, iounit_release_scsi_one, BTFIXUPCALL_NORM);
 263         BTFIXUPSET_CALL(mmu_release_scsi_sgl, iounit_release_scsi_sgl, BTFIXUPCALL_NORM);
 264
 265 #ifdef CONFIG_SBUS
 266         BTFIXUPSET_CALL(mmu_map_dma_area, iounit_map_dma_area, BTFIXUPCALL_NORM);
 267         BTFIXUPSET_CALL(mmu_unmap_dma_area, iounit_unmap_dma_area, BTFIXUPCALL_NORM);
 268         BTFIXUPSET_CALL(mmu_translate_dvma, iounit_translate_dvma, BTFIXUPCALL_NORM);
 269 #endif
 270 }
 271
 272 __u32 iounit_map_dma_init(struct sbus_bus *sbus, int size)
 273 {
 274         int i, j, k, npages;
 275         unsigned long rotor, scan, limit;
 276         unsigned long flags;
 277         __u32 ret;
 278         struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
 279
 280         npages = (size + (PAGE_SIZE-1)) >> PAGE_SHIFT;
 281         i = 0x0213;
 282         spin_lock_irqsave(&iounit->lock, flags);
 283 next:   j = (i & 15);
 284         rotor = iounit->rotor[j - 1];
 285         limit = iounit->limit[j];
 286         scan = rotor;
 287 nexti:  scan = find_next_zero_bit(iounit->bmap, limit, scan);
 288         if (scan + npages > limit) {
 289                 if (limit != rotor) {
 290                         limit = rotor;
 291                         scan = iounit->limit[j - 1];
 292                         goto nexti;
 293                 }
 294                 i >>= 4;
 295                 if (!(i & 15))
 296                         panic("iounit_map_dma_init: Couldn't find free iopte slots for %d bytes\n", size);
 297                 goto next;
 298         }
 299         for (k = 1, scan++; k < npages; k++)
 300                 if (test_bit(scan++, iounit->bmap))
 301                         goto nexti;
 302         iounit->rotor[j - 1] = (scan < limit) ? scan : iounit->limit[j - 1];
 303         scan -= npages;
 304         ret = IOUNIT_DMA_BASE + (scan << PAGE_SHIFT);
 305         for (k = 0; k < npages; k++, scan++)
 306                 set_bit(scan, iounit->bmap);
 307         spin_unlock_irqrestore(&iounit->lock, flags);
 308         return ret;
 309 }
 310
 311 __u32 iounit_map_dma_page(__u32 vaddr, void *addr, struct sbus_bus *sbus)
 312 {
 313         int scan = (vaddr - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
 314         struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
 315
 316         iounit->page_table[scan] = MKIOPTE(__pa(((unsigned long)addr) & PAGE_MASK));
 317         return vaddr + (((unsigned long)addr) & ~PAGE_MASK);
 318 }