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/kernel.h>
8 #include <linux/init.h>
9 #include <linux/slab.h>
10 #include <linux/spinlock.h>
12 #include <linux/highmem.h> /* pte_offset_map => kmap_atomic */
13 #include <linux/bitops.h>
15 #include <asm/scatterlist.h>
16 #include <asm/pgalloc.h>
17 #include <asm/pgtable.h>
20 #include <asm/io-unit.h>
22 #include <asm/cacheflush.h>
23 #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;
55 if(prom_getproperty(sbi_node, "reg", (void *) iommu_promregs,
56 sizeof(iommu_promregs)) != -1) {
57 prom_apply_generic_ranges(io_node, 0, iommu_promregs, 3);
58 memset(&r, 0, sizeof(r));
59 r.flags = iommu_promregs[2].which_io;
60 r.start = iommu_promregs[2].phys_addr;
61 xpt = (iopte_t *) sbus_ioremap(&r, 0, PAGE_SIZE * 16, "XPT");
63 if(!xpt) panic("Cannot map External Page Table.");
65 sbus->iommu = (struct iommu_struct *)iounit;
66 iounit->page_table = xpt;
68 for (xptend = iounit->page_table + (16 * PAGE_SIZE) / sizeof(iopte_t);
70 iopte_val(*xpt++) = 0;
73 /* One has to hold iounit->lock to call this */
74 static unsigned long iounit_get_area(struct iounit_struct *iounit, unsigned long vaddr, int size)
77 unsigned long rotor, scan, limit;
80 npages = ((vaddr & ~PAGE_MASK) + size + (PAGE_SIZE-1)) >> PAGE_SHIFT;
82 /* A tiny bit of magic ingredience :) */
84 case 1: i = 0x0231; break;
85 case 2: i = 0x0132; break;
86 default: i = 0x0213; break;
89 IOD(("iounit_get_area(%08lx,%d[%d])=", vaddr, size, npages));
92 rotor = iounit->rotor[j - 1];
93 limit = iounit->limit[j];
95 nexti: scan = find_next_zero_bit(iounit->bmap, limit, scan);
96 if (scan + npages > limit) {
99 scan = iounit->limit[j - 1];
104 panic("iounit_get_area: Couldn't find free iopte slots for (%08lx,%d)\n", vaddr, size);
107 for (k = 1, scan++; k < npages; k++)
108 if (test_bit(scan++, iounit->bmap))
110 iounit->rotor[j - 1] = (scan < limit) ? scan : iounit->limit[j - 1];
112 iopte = MKIOPTE(__pa(vaddr & PAGE_MASK));
113 vaddr = IOUNIT_DMA_BASE + (scan << PAGE_SHIFT) + (vaddr & ~PAGE_MASK);
114 for (k = 0; k < npages; k++, iopte = __iopte(iopte_val(iopte) + 0x100), scan++) {
115 set_bit(scan, iounit->bmap);
116 iounit->page_table[scan] = iopte;
118 IOD(("%08lx\n", vaddr));
122 static __u32 iounit_get_scsi_one(char *vaddr, unsigned long len, struct sbus_bus *sbus)
124 unsigned long ret, flags;
125 struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
127 spin_lock_irqsave(&iounit->lock, flags);
128 ret = iounit_get_area(iounit, (unsigned long)vaddr, len);
129 spin_unlock_irqrestore(&iounit->lock, flags);
133 static void iounit_get_scsi_sgl(struct scatterlist *sg, int sz, struct sbus_bus *sbus)
136 struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
138 /* FIXME: Cache some resolved pages - often several sg entries are to the same page */
139 spin_lock_irqsave(&iounit->lock, flags);
142 sg[sz].dvma_address = iounit_get_area(iounit, (unsigned long)page_address(sg[sz].page) + sg[sz].offset, sg[sz].length);
143 sg[sz].dvma_length = sg[sz].length;
145 spin_unlock_irqrestore(&iounit->lock, flags);
148 static void iounit_release_scsi_one(__u32 vaddr, unsigned long len, struct sbus_bus *sbus)
151 struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
153 spin_lock_irqsave(&iounit->lock, flags);
154 len = ((vaddr & ~PAGE_MASK) + len + (PAGE_SIZE-1)) >> PAGE_SHIFT;
155 vaddr = (vaddr - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
156 IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr));
157 for (len += vaddr; vaddr < len; vaddr++)
158 clear_bit(vaddr, iounit->bmap);
159 spin_unlock_irqrestore(&iounit->lock, flags);
162 static void iounit_release_scsi_sgl(struct scatterlist *sg, int sz, struct sbus_bus *sbus)
165 unsigned long vaddr, len;
166 struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
168 spin_lock_irqsave(&iounit->lock, flags);
171 len = ((sg[sz].dvma_address & ~PAGE_MASK) + sg[sz].length + (PAGE_SIZE-1)) >> PAGE_SHIFT;
172 vaddr = (sg[sz].dvma_address - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
173 IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr));
174 for (len += vaddr; vaddr < len; vaddr++)
175 clear_bit(vaddr, iounit->bmap);
177 spin_unlock_irqrestore(&iounit->lock, flags);
181 static int iounit_map_dma_area(dma_addr_t *pba, unsigned long va, __u32 addr, int len)
183 unsigned long page, end;
186 struct sbus_bus *sbus;
190 dvma_prot = __pgprot(SRMMU_CACHE | SRMMU_ET_PTE | SRMMU_PRIV);
191 end = PAGE_ALIGN((addr + len));
200 pgdp = pgd_offset(&init_mm, addr);
201 pmdp = pmd_offset(pgdp, addr);
202 ptep = pte_offset_map(pmdp, addr);
204 set_pte(ptep, mk_pte(virt_to_page(page), dvma_prot));
206 i = ((addr - IOUNIT_DMA_BASE) >> PAGE_SHIFT);
208 for_each_sbus(sbus) {
209 struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
211 iopte = (iopte_t *)(iounit->page_table + i);
212 *iopte = MKIOPTE(__pa(page));
224 static void iounit_unmap_dma_area(unsigned long addr, int len)
226 /* XXX Somebody please fill this in */
229 /* XXX We do not pass sbus device here, bad. */
230 static struct page *iounit_translate_dvma(unsigned long addr)
232 struct sbus_bus *sbus = sbus_root; /* They are all the same */
233 struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
237 i = ((addr - IOUNIT_DMA_BASE) >> PAGE_SHIFT);
238 iopte = (iopte_t *)(iounit->page_table + i);
239 return pfn_to_page(iopte_val(*iopte) >> (PAGE_SHIFT-4)); /* XXX sun4d guru, help */
243 static char *iounit_lockarea(char *vaddr, unsigned long len)
245 /* FIXME: Write this */
249 static void iounit_unlockarea(char *vaddr, unsigned long len)
251 /* FIXME: Write this */
254 void __init ld_mmu_iounit(void)
256 BTFIXUPSET_CALL(mmu_lockarea, iounit_lockarea, BTFIXUPCALL_RETO0);
257 BTFIXUPSET_CALL(mmu_unlockarea, iounit_unlockarea, BTFIXUPCALL_NOP);
259 BTFIXUPSET_CALL(mmu_get_scsi_one, iounit_get_scsi_one, BTFIXUPCALL_NORM);
260 BTFIXUPSET_CALL(mmu_get_scsi_sgl, iounit_get_scsi_sgl, BTFIXUPCALL_NORM);
261 BTFIXUPSET_CALL(mmu_release_scsi_one, iounit_release_scsi_one, BTFIXUPCALL_NORM);
262 BTFIXUPSET_CALL(mmu_release_scsi_sgl, iounit_release_scsi_sgl, BTFIXUPCALL_NORM);
265 BTFIXUPSET_CALL(mmu_map_dma_area, iounit_map_dma_area, BTFIXUPCALL_NORM);
266 BTFIXUPSET_CALL(mmu_unmap_dma_area, iounit_unmap_dma_area, BTFIXUPCALL_NORM);
267 BTFIXUPSET_CALL(mmu_translate_dvma, iounit_translate_dvma, BTFIXUPCALL_NORM);
271 __u32 iounit_map_dma_init(struct sbus_bus *sbus, int size)
274 unsigned long rotor, scan, limit;
277 struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
279 npages = (size + (PAGE_SIZE-1)) >> PAGE_SHIFT;
281 spin_lock_irqsave(&iounit->lock, flags);
283 rotor = iounit->rotor[j - 1];
284 limit = iounit->limit[j];
286 nexti: scan = find_next_zero_bit(iounit->bmap, limit, scan);
287 if (scan + npages > limit) {
288 if (limit != rotor) {
290 scan = iounit->limit[j - 1];
295 panic("iounit_map_dma_init: Couldn't find free iopte slots for %d bytes\n", size);
298 for (k = 1, scan++; k < npages; k++)
299 if (test_bit(scan++, iounit->bmap))
301 iounit->rotor[j - 1] = (scan < limit) ? scan : iounit->limit[j - 1];
303 ret = IOUNIT_DMA_BASE + (scan << PAGE_SHIFT);
304 for (k = 0; k < npages; k++, scan++)
305 set_bit(scan, iounit->bmap);
306 spin_unlock_irqrestore(&iounit->lock, flags);
310 __u32 iounit_map_dma_page(__u32 vaddr, void *addr, struct sbus_bus *sbus)
312 int scan = (vaddr - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
313 struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
315 iounit->page_table[scan] = MKIOPTE(__pa(((unsigned long)addr) & PAGE_MASK));
316 return vaddr + (((unsigned long)addr) & ~PAGE_MASK);