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.
4 * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
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>
13 #include <linux/highmem.h> /* pte_offset_map => kmap_atomic */
15 #include <asm/scatterlist.h>
16 #include <asm/pgalloc.h>
17 #include <asm/pgtable.h>
20 #include <asm/io-unit.h>
22 #include <asm/bitops.h>
23 #include <asm/cacheflush.h>
24 #include <asm/tlbflush.h>
26 /* #define IOUNIT_DEBUG */
28 #define IOD(x) printk(x)
30 #define IOD(x) do { } while (0)
33 #define IOPERM (IOUPTE_CACHE | IOUPTE_WRITE | IOUPTE_VALID)
34 #define MKIOPTE(phys) __iopte((((phys)>>4) & IOUPTE_PAGE) | IOPERM)
37 iounit_init(int sbi_node, int io_node, struct sbus_bus *sbus)
39 iopte_t *xpt, *xptend;
40 struct iounit_struct *iounit;
41 struct linux_prom_registers iommu_promregs[PROMREG_MAX];
44 iounit = kmalloc(sizeof(struct iounit_struct), GFP_ATOMIC);
46 memset(iounit, 0, sizeof(*iounit));
47 iounit->limit[0] = IOUNIT_BMAP1_START;
48 iounit->limit[1] = IOUNIT_BMAP2_START;
49 iounit->limit[2] = IOUNIT_BMAPM_START;
50 iounit->limit[3] = IOUNIT_BMAPM_END;
51 iounit->rotor[1] = IOUNIT_BMAP2_START;
52 iounit->rotor[2] = IOUNIT_BMAPM_START;
54 prom_getproperty(sbi_node, "reg", (void *) iommu_promregs,
55 sizeof(iommu_promregs));
56 prom_apply_generic_ranges(io_node, 0, iommu_promregs, 3);
57 memset(&r, 0, sizeof(r));
58 r.flags = iommu_promregs[2].which_io;
59 r.start = iommu_promregs[2].phys_addr;
60 xpt = (iopte_t *) sbus_ioremap(&r, 0, PAGE_SIZE * 16, "XPT");
61 if(!xpt) panic("Cannot map External Page Table.");
63 sbus->iommu = (struct iommu_struct *)iounit;
64 iounit->page_table = xpt;
66 for (xptend = iounit->page_table + (16 * PAGE_SIZE) / sizeof(iopte_t);
68 iopte_val(*xpt++) = 0;
71 /* One has to hold iounit->lock to call this */
72 static unsigned long iounit_get_area(struct iounit_struct *iounit, unsigned long vaddr, int size)
75 unsigned long rotor, scan, limit;
78 npages = ((vaddr & ~PAGE_MASK) + size + (PAGE_SIZE-1)) >> PAGE_SHIFT;
80 /* A tiny bit of magic ingredience :) */
82 case 1: i = 0x0231; break;
83 case 2: i = 0x0132; break;
84 default: i = 0x0213; break;
87 IOD(("iounit_get_area(%08lx,%d[%d])=", vaddr, size, npages));
90 rotor = iounit->rotor[j - 1];
91 limit = iounit->limit[j];
93 nexti: scan = find_next_zero_bit(iounit->bmap, limit, scan);
94 if (scan + npages > limit) {
97 scan = iounit->limit[j - 1];
102 panic("iounit_get_area: Couldn't find free iopte slots for (%08lx,%d)\n", vaddr, size);
105 for (k = 1, scan++; k < npages; k++)
106 if (test_bit(scan++, iounit->bmap))
108 iounit->rotor[j - 1] = (scan < limit) ? scan : iounit->limit[j - 1];
110 iopte = MKIOPTE(__pa(vaddr & PAGE_MASK));
111 vaddr = IOUNIT_DMA_BASE + (scan << PAGE_SHIFT) + (vaddr & ~PAGE_MASK);
112 for (k = 0; k < npages; k++, iopte = __iopte(iopte_val(iopte) + 0x100), scan++) {
113 set_bit(scan, iounit->bmap);
114 iounit->page_table[scan] = iopte;
116 IOD(("%08lx\n", vaddr));
120 static __u32 iounit_get_scsi_one(char *vaddr, unsigned long len, struct sbus_bus *sbus)
122 unsigned long ret, flags;
123 struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
125 spin_lock_irqsave(&iounit->lock, flags);
126 ret = iounit_get_area(iounit, (unsigned long)vaddr, len);
127 spin_unlock_irqrestore(&iounit->lock, flags);
131 static void iounit_get_scsi_sgl(struct scatterlist *sg, int sz, struct sbus_bus *sbus)
134 struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
136 /* FIXME: Cache some resolved pages - often several sg entries are to the same page */
137 spin_lock_irqsave(&iounit->lock, flags);
140 sg[sz].dvma_address = iounit_get_area(iounit, (unsigned long)page_address(sg[sz].page) + sg[sz].offset, sg[sz].length);
141 sg[sz].dvma_length = sg[sz].length;
143 spin_unlock_irqrestore(&iounit->lock, flags);
146 static void iounit_release_scsi_one(__u32 vaddr, unsigned long len, struct sbus_bus *sbus)
149 struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
151 spin_lock_irqsave(&iounit->lock, flags);
152 len = ((vaddr & ~PAGE_MASK) + len + (PAGE_SIZE-1)) >> PAGE_SHIFT;
153 vaddr = (vaddr - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
154 IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr));
155 for (len += vaddr; vaddr < len; vaddr++)
156 clear_bit(vaddr, iounit->bmap);
157 spin_unlock_irqrestore(&iounit->lock, flags);
160 static void iounit_release_scsi_sgl(struct scatterlist *sg, int sz, struct sbus_bus *sbus)
163 unsigned long vaddr, len;
164 struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
166 spin_lock_irqsave(&iounit->lock, flags);
169 len = ((sg[sz].dvma_address & ~PAGE_MASK) + sg[sz].length + (PAGE_SIZE-1)) >> PAGE_SHIFT;
170 vaddr = (sg[sz].dvma_address - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
171 IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr));
172 for (len += vaddr; vaddr < len; vaddr++)
173 clear_bit(vaddr, iounit->bmap);
175 spin_unlock_irqrestore(&iounit->lock, flags);
179 static int iounit_map_dma_area(dma_addr_t *pba, unsigned long va, __u32 addr, int len)
181 unsigned long page, end;
184 struct sbus_bus *sbus;
188 dvma_prot = __pgprot(SRMMU_CACHE | SRMMU_ET_PTE | SRMMU_PRIV);
189 end = PAGE_ALIGN((addr + len));
198 pgdp = pgd_offset(init_task.mm, addr);
199 pmdp = pmd_offset(pgdp, addr);
200 ptep = pte_offset_map(pmdp, addr);
202 set_pte(ptep, mk_pte(virt_to_page(page), dvma_prot));
204 i = ((addr - IOUNIT_DMA_BASE) >> PAGE_SHIFT);
206 for_each_sbus(sbus) {
207 struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
209 iopte = (iopte_t *)(iounit->page_table + i);
210 *iopte = MKIOPTE(__pa(page));
222 static void iounit_unmap_dma_area(unsigned long addr, int len)
224 /* XXX Somebody please fill this in */
227 /* XXX We do not pass sbus device here, bad. */
228 static struct page *iounit_translate_dvma(unsigned long addr)
230 struct sbus_bus *sbus = sbus_root; /* They are all the same */
231 struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
235 i = ((addr - IOUNIT_DMA_BASE) >> PAGE_SHIFT);
236 iopte = (iopte_t *)(iounit->page_table + i);
237 return pfn_to_page(iopte_val(*iopte) >> (PAGE_SHIFT-4)); /* XXX sun4d guru, help */
241 static char *iounit_lockarea(char *vaddr, unsigned long len)
243 /* FIXME: Write this */
247 static void iounit_unlockarea(char *vaddr, unsigned long len)
249 /* FIXME: Write this */
252 void __init ld_mmu_iounit(void)
254 BTFIXUPSET_CALL(mmu_lockarea, iounit_lockarea, BTFIXUPCALL_RETO0);
255 BTFIXUPSET_CALL(mmu_unlockarea, iounit_unlockarea, BTFIXUPCALL_NOP);
257 BTFIXUPSET_CALL(mmu_get_scsi_one, iounit_get_scsi_one, BTFIXUPCALL_NORM);
258 BTFIXUPSET_CALL(mmu_get_scsi_sgl, iounit_get_scsi_sgl, BTFIXUPCALL_NORM);
259 BTFIXUPSET_CALL(mmu_release_scsi_one, iounit_release_scsi_one, BTFIXUPCALL_NORM);
260 BTFIXUPSET_CALL(mmu_release_scsi_sgl, iounit_release_scsi_sgl, BTFIXUPCALL_NORM);
263 BTFIXUPSET_CALL(mmu_map_dma_area, iounit_map_dma_area, BTFIXUPCALL_NORM);
264 BTFIXUPSET_CALL(mmu_unmap_dma_area, iounit_unmap_dma_area, BTFIXUPCALL_NORM);
265 BTFIXUPSET_CALL(mmu_translate_dvma, iounit_translate_dvma, BTFIXUPCALL_NORM);
269 __u32 iounit_map_dma_init(struct sbus_bus *sbus, int size)
272 unsigned long rotor, scan, limit;
275 struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
277 npages = (size + (PAGE_SIZE-1)) >> PAGE_SHIFT;
279 spin_lock_irqsave(&iounit->lock, flags);
281 rotor = iounit->rotor[j - 1];
282 limit = iounit->limit[j];
284 nexti: scan = find_next_zero_bit(iounit->bmap, limit, scan);
285 if (scan + npages > limit) {
286 if (limit != rotor) {
288 scan = iounit->limit[j - 1];
293 panic("iounit_map_dma_init: Couldn't find free iopte slots for %d bytes\n", size);
296 for (k = 1, scan++; k < npages; k++)
297 if (test_bit(scan++, iounit->bmap))
299 iounit->rotor[j - 1] = (scan < limit) ? scan : iounit->limit[j - 1];
301 ret = IOUNIT_DMA_BASE + (scan << PAGE_SHIFT);
302 for (k = 0; k < npages; k++, scan++)
303 set_bit(scan, iounit->bmap);
304 spin_unlock_irqrestore(&iounit->lock, flags);
308 __u32 iounit_map_dma_page(__u32 vaddr, void *addr, struct sbus_bus *sbus)
310 int scan = (vaddr - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
311 struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
313 iounit->page_table[scan] = MKIOPTE(__pa(((unsigned long)addr) & PAGE_MASK));
314 return vaddr + (((unsigned long)addr) & ~PAGE_MASK);