Linux 3.11-rc3
[cris-mirror.git] / arch / sparc / mm / io-unit.c
blobeb99862e9654edb7aba01568cfda499e5be79983
1 /*
2 * io-unit.c: IO-UNIT specific routines for memory management.
4 * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
5 */
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>
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>
28 /* #define IOUNIT_DEBUG */
29 #ifdef IOUNIT_DEBUG
30 #define IOD(x) printk(x)
31 #else
32 #define IOD(x) do { } while (0)
33 #endif
35 #define IOPERM (IOUPTE_CACHE | IOUPTE_WRITE | IOUPTE_VALID)
36 #define MKIOPTE(phys) __iopte((((phys)>>4) & IOUPTE_PAGE) | IOPERM)
38 static void __init iounit_iommu_init(struct platform_device *op)
40 struct iounit_struct *iounit;
41 iopte_t *xpt, *xptend;
43 iounit = kzalloc(sizeof(struct iounit_struct), GFP_ATOMIC);
44 if (!iounit) {
45 prom_printf("SUN4D: Cannot alloc iounit, halting.\n");
46 prom_halt();
49 iounit->limit[0] = IOUNIT_BMAP1_START;
50 iounit->limit[1] = IOUNIT_BMAP2_START;
51 iounit->limit[2] = IOUNIT_BMAPM_START;
52 iounit->limit[3] = IOUNIT_BMAPM_END;
53 iounit->rotor[1] = IOUNIT_BMAP2_START;
54 iounit->rotor[2] = IOUNIT_BMAPM_START;
56 xpt = of_ioremap(&op->resource[2], 0, PAGE_SIZE * 16, "XPT");
57 if (!xpt) {
58 prom_printf("SUN4D: Cannot map External Page Table.");
59 prom_halt();
62 op->dev.archdata.iommu = iounit;
63 iounit->page_table = xpt;
64 spin_lock_init(&iounit->lock);
66 for (xptend = iounit->page_table + (16 * PAGE_SIZE) / sizeof(iopte_t);
67 xpt < xptend;)
68 iopte_val(*xpt++) = 0;
71 static int __init iounit_init(void)
73 extern void sun4d_init_sbi_irq(void);
74 struct device_node *dp;
76 for_each_node_by_name(dp, "sbi") {
77 struct platform_device *op = of_find_device_by_node(dp);
79 iounit_iommu_init(op);
80 of_propagate_archdata(op);
83 sun4d_init_sbi_irq();
85 return 0;
88 subsys_initcall(iounit_init);
90 /* One has to hold iounit->lock to call this */
91 static unsigned long iounit_get_area(struct iounit_struct *iounit, unsigned long vaddr, int size)
93 int i, j, k, npages;
94 unsigned long rotor, scan, limit;
95 iopte_t iopte;
97 npages = ((vaddr & ~PAGE_MASK) + size + (PAGE_SIZE-1)) >> PAGE_SHIFT;
99 /* A tiny bit of magic ingredience :) */
100 switch (npages) {
101 case 1: i = 0x0231; break;
102 case 2: i = 0x0132; break;
103 default: i = 0x0213; break;
106 IOD(("iounit_get_area(%08lx,%d[%d])=", vaddr, size, npages));
108 next: j = (i & 15);
109 rotor = iounit->rotor[j - 1];
110 limit = iounit->limit[j];
111 scan = rotor;
112 nexti: scan = find_next_zero_bit(iounit->bmap, limit, scan);
113 if (scan + npages > limit) {
114 if (limit != rotor) {
115 limit = rotor;
116 scan = iounit->limit[j - 1];
117 goto nexti;
119 i >>= 4;
120 if (!(i & 15))
121 panic("iounit_get_area: Couldn't find free iopte slots for (%08lx,%d)\n", vaddr, size);
122 goto next;
124 for (k = 1, scan++; k < npages; k++)
125 if (test_bit(scan++, iounit->bmap))
126 goto nexti;
127 iounit->rotor[j - 1] = (scan < limit) ? scan : iounit->limit[j - 1];
128 scan -= npages;
129 iopte = MKIOPTE(__pa(vaddr & PAGE_MASK));
130 vaddr = IOUNIT_DMA_BASE + (scan << PAGE_SHIFT) + (vaddr & ~PAGE_MASK);
131 for (k = 0; k < npages; k++, iopte = __iopte(iopte_val(iopte) + 0x100), scan++) {
132 set_bit(scan, iounit->bmap);
133 iounit->page_table[scan] = iopte;
135 IOD(("%08lx\n", vaddr));
136 return vaddr;
139 static __u32 iounit_get_scsi_one(struct device *dev, char *vaddr, unsigned long len)
141 struct iounit_struct *iounit = dev->archdata.iommu;
142 unsigned long ret, flags;
144 spin_lock_irqsave(&iounit->lock, flags);
145 ret = iounit_get_area(iounit, (unsigned long)vaddr, len);
146 spin_unlock_irqrestore(&iounit->lock, flags);
147 return ret;
150 static void iounit_get_scsi_sgl(struct device *dev, struct scatterlist *sg, int sz)
152 struct iounit_struct *iounit = dev->archdata.iommu;
153 unsigned long flags;
155 /* FIXME: Cache some resolved pages - often several sg entries are to the same page */
156 spin_lock_irqsave(&iounit->lock, flags);
157 while (sz != 0) {
158 --sz;
159 sg->dma_address = iounit_get_area(iounit, (unsigned long) sg_virt(sg), sg->length);
160 sg->dma_length = sg->length;
161 sg = sg_next(sg);
163 spin_unlock_irqrestore(&iounit->lock, flags);
166 static void iounit_release_scsi_one(struct device *dev, __u32 vaddr, unsigned long len)
168 struct iounit_struct *iounit = dev->archdata.iommu;
169 unsigned long flags;
171 spin_lock_irqsave(&iounit->lock, flags);
172 len = ((vaddr & ~PAGE_MASK) + len + (PAGE_SIZE-1)) >> PAGE_SHIFT;
173 vaddr = (vaddr - 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 spin_unlock_irqrestore(&iounit->lock, flags);
180 static void iounit_release_scsi_sgl(struct device *dev, struct scatterlist *sg, int sz)
182 struct iounit_struct *iounit = dev->archdata.iommu;
183 unsigned long flags;
184 unsigned long vaddr, len;
186 spin_lock_irqsave(&iounit->lock, flags);
187 while (sz != 0) {
188 --sz;
189 len = ((sg->dma_address & ~PAGE_MASK) + sg->length + (PAGE_SIZE-1)) >> PAGE_SHIFT;
190 vaddr = (sg->dma_address - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
191 IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr));
192 for (len += vaddr; vaddr < len; vaddr++)
193 clear_bit(vaddr, iounit->bmap);
194 sg = sg_next(sg);
196 spin_unlock_irqrestore(&iounit->lock, flags);
199 #ifdef CONFIG_SBUS
200 static int iounit_map_dma_area(struct device *dev, dma_addr_t *pba, unsigned long va, unsigned long addr, int len)
202 struct iounit_struct *iounit = dev->archdata.iommu;
203 unsigned long page, end;
204 pgprot_t dvma_prot;
205 iopte_t *iopte;
207 *pba = addr;
209 dvma_prot = __pgprot(SRMMU_CACHE | SRMMU_ET_PTE | SRMMU_PRIV);
210 end = PAGE_ALIGN((addr + len));
211 while(addr < end) {
212 page = va;
214 pgd_t *pgdp;
215 pmd_t *pmdp;
216 pte_t *ptep;
217 long i;
219 pgdp = pgd_offset(&init_mm, addr);
220 pmdp = pmd_offset(pgdp, addr);
221 ptep = pte_offset_map(pmdp, addr);
223 set_pte(ptep, mk_pte(virt_to_page(page), dvma_prot));
225 i = ((addr - IOUNIT_DMA_BASE) >> PAGE_SHIFT);
227 iopte = (iopte_t *)(iounit->page_table + i);
228 *iopte = MKIOPTE(__pa(page));
230 addr += PAGE_SIZE;
231 va += PAGE_SIZE;
233 flush_cache_all();
234 flush_tlb_all();
236 return 0;
239 static void iounit_unmap_dma_area(struct device *dev, unsigned long addr, int len)
241 /* XXX Somebody please fill this in */
243 #endif
245 static const struct sparc32_dma_ops iounit_dma_ops = {
246 .get_scsi_one = iounit_get_scsi_one,
247 .get_scsi_sgl = iounit_get_scsi_sgl,
248 .release_scsi_one = iounit_release_scsi_one,
249 .release_scsi_sgl = iounit_release_scsi_sgl,
250 #ifdef CONFIG_SBUS
251 .map_dma_area = iounit_map_dma_area,
252 .unmap_dma_area = iounit_unmap_dma_area,
253 #endif
256 void __init ld_mmu_iounit(void)
258 sparc32_dma_ops = &iounit_dma_ops;