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 #include <linux/of.h>
16 #include <linux/of_device.h>
17
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>
27
28 #include "mm_32.h"
29
30 /* #define IOUNIT_DEBUG */
31 #ifdef IOUNIT_DEBUG
32 #define IOD(x) printk(x)
33 #else
34 #define IOD(x) do { } while (0)
35 #endif
36
37 #define IOPERM (IOUPTE_CACHE | IOUPTE_WRITE | IOUPTE_VALID)
38 #define MKIOPTE(phys) __iopte((((phys)>>4) & IOUPTE_PAGE) | IOPERM)
39
iounit_iommu_init(struct platform_device * op)40 static void __init iounit_iommu_init(struct platform_device *op)
41 {
42 struct iounit_struct *iounit;
43 iopte_t __iomem *xpt;
44 iopte_t __iomem *xptend;
45
46 iounit = kzalloc(sizeof(struct iounit_struct), GFP_ATOMIC);
47 if (!iounit) {
48 prom_printf("SUN4D: Cannot alloc iounit, halting.\n");
49 prom_halt();
50 }
51
52 iounit->limit[0] = IOUNIT_BMAP1_START;
53 iounit->limit[1] = IOUNIT_BMAP2_START;
54 iounit->limit[2] = IOUNIT_BMAPM_START;
55 iounit->limit[3] = IOUNIT_BMAPM_END;
56 iounit->rotor[1] = IOUNIT_BMAP2_START;
57 iounit->rotor[2] = IOUNIT_BMAPM_START;
58
59 xpt = of_ioremap(&op->resource[2], 0, PAGE_SIZE * 16, "XPT");
60 if (!xpt) {
61 prom_printf("SUN4D: Cannot map External Page Table.");
62 prom_halt();
63 }
64
65 op->dev.archdata.iommu = iounit;
66 iounit->page_table = xpt;
67 spin_lock_init(&iounit->lock);
68
69 xptend = iounit->page_table + (16 * PAGE_SIZE) / sizeof(iopte_t);
70 for (; xpt < xptend; xpt++)
71 sbus_writel(0, xpt);
72 }
73
iounit_init(void)74 static int __init iounit_init(void)
75 {
76 extern void sun4d_init_sbi_irq(void);
77 struct device_node *dp;
78
79 for_each_node_by_name(dp, "sbi") {
80 struct platform_device *op = of_find_device_by_node(dp);
81
82 iounit_iommu_init(op);
83 of_propagate_archdata(op);
84 }
85
86 sun4d_init_sbi_irq();
87
88 return 0;
89 }
90
91 subsys_initcall(iounit_init);
92
93 /* One has to hold iounit->lock to call this */
iounit_get_area(struct iounit_struct * iounit,unsigned long vaddr,int size)94 static unsigned long iounit_get_area(struct iounit_struct *iounit, unsigned long vaddr, int size)
95 {
96 int i, j, k, npages;
97 unsigned long rotor, scan, limit;
98 iopte_t iopte;
99
100 npages = ((vaddr & ~PAGE_MASK) + size + (PAGE_SIZE-1)) >> PAGE_SHIFT;
101
102 /* A tiny bit of magic ingredience :) */
103 switch (npages) {
104 case 1: i = 0x0231; break;
105 case 2: i = 0x0132; break;
106 default: i = 0x0213; break;
107 }
108
109 IOD(("iounit_get_area(%08lx,%d[%d])=", vaddr, size, npages));
110
111 next: j = (i & 15);
112 rotor = iounit->rotor[j - 1];
113 limit = iounit->limit[j];
114 scan = rotor;
115 nexti: scan = find_next_zero_bit(iounit->bmap, limit, scan);
116 if (scan + npages > limit) {
117 if (limit != rotor) {
118 limit = rotor;
119 scan = iounit->limit[j - 1];
120 goto nexti;
121 }
122 i >>= 4;
123 if (!(i & 15))
124 panic("iounit_get_area: Couldn't find free iopte slots for (%08lx,%d)\n", vaddr, size);
125 goto next;
126 }
127 for (k = 1, scan++; k < npages; k++)
128 if (test_bit(scan++, iounit->bmap))
129 goto nexti;
130 iounit->rotor[j - 1] = (scan < limit) ? scan : iounit->limit[j - 1];
131 scan -= npages;
132 iopte = MKIOPTE(__pa(vaddr & PAGE_MASK));
133 vaddr = IOUNIT_DMA_BASE + (scan << PAGE_SHIFT) + (vaddr & ~PAGE_MASK);
134 for (k = 0; k < npages; k++, iopte = __iopte(iopte_val(iopte) + 0x100), scan++) {
135 set_bit(scan, iounit->bmap);
136 sbus_writel(iopte, &iounit->page_table[scan]);
137 }
138 IOD(("%08lx\n", vaddr));
139 return vaddr;
140 }
141
iounit_get_scsi_one(struct device * dev,char * vaddr,unsigned long len)142 static __u32 iounit_get_scsi_one(struct device *dev, char *vaddr, unsigned long len)
143 {
144 struct iounit_struct *iounit = dev->archdata.iommu;
145 unsigned long ret, flags;
146
147 spin_lock_irqsave(&iounit->lock, flags);
148 ret = iounit_get_area(iounit, (unsigned long)vaddr, len);
149 spin_unlock_irqrestore(&iounit->lock, flags);
150 return ret;
151 }
152
iounit_get_scsi_sgl(struct device * dev,struct scatterlist * sg,int sz)153 static void iounit_get_scsi_sgl(struct device *dev, struct scatterlist *sg, int sz)
154 {
155 struct iounit_struct *iounit = dev->archdata.iommu;
156 unsigned long flags;
157
158 /* FIXME: Cache some resolved pages - often several sg entries are to the same page */
159 spin_lock_irqsave(&iounit->lock, flags);
160 while (sz != 0) {
161 --sz;
162 sg->dma_address = iounit_get_area(iounit, (unsigned long) sg_virt(sg), sg->length);
163 sg->dma_length = sg->length;
164 sg = sg_next(sg);
165 }
166 spin_unlock_irqrestore(&iounit->lock, flags);
167 }
168
iounit_release_scsi_one(struct device * dev,__u32 vaddr,unsigned long len)169 static void iounit_release_scsi_one(struct device *dev, __u32 vaddr, unsigned long len)
170 {
171 struct iounit_struct *iounit = dev->archdata.iommu;
172 unsigned long flags;
173
174 spin_lock_irqsave(&iounit->lock, flags);
175 len = ((vaddr & ~PAGE_MASK) + len + (PAGE_SIZE-1)) >> PAGE_SHIFT;
176 vaddr = (vaddr - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
177 IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr));
178 for (len += vaddr; vaddr < len; vaddr++)
179 clear_bit(vaddr, iounit->bmap);
180 spin_unlock_irqrestore(&iounit->lock, flags);
181 }
182
iounit_release_scsi_sgl(struct device * dev,struct scatterlist * sg,int sz)183 static void iounit_release_scsi_sgl(struct device *dev, struct scatterlist *sg, int sz)
184 {
185 struct iounit_struct *iounit = dev->archdata.iommu;
186 unsigned long flags;
187 unsigned long vaddr, len;
188
189 spin_lock_irqsave(&iounit->lock, flags);
190 while (sz != 0) {
191 --sz;
192 len = ((sg->dma_address & ~PAGE_MASK) + sg->length + (PAGE_SIZE-1)) >> PAGE_SHIFT;
193 vaddr = (sg->dma_address - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
194 IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr));
195 for (len += vaddr; vaddr < len; vaddr++)
196 clear_bit(vaddr, iounit->bmap);
197 sg = sg_next(sg);
198 }
199 spin_unlock_irqrestore(&iounit->lock, flags);
200 }
201
202 #ifdef CONFIG_SBUS
iounit_map_dma_area(struct device * dev,dma_addr_t * pba,unsigned long va,unsigned long addr,int len)203 static int iounit_map_dma_area(struct device *dev, dma_addr_t *pba, unsigned long va, unsigned long addr, int len)
204 {
205 struct iounit_struct *iounit = dev->archdata.iommu;
206 unsigned long page, end;
207 pgprot_t dvma_prot;
208 iopte_t __iomem *iopte;
209
210 *pba = addr;
211
212 dvma_prot = __pgprot(SRMMU_CACHE | SRMMU_ET_PTE | SRMMU_PRIV);
213 end = PAGE_ALIGN((addr + len));
214 while(addr < end) {
215 page = va;
216 {
217 pgd_t *pgdp;
218 pmd_t *pmdp;
219 pte_t *ptep;
220 long i;
221
222 pgdp = pgd_offset(&init_mm, addr);
223 pmdp = pmd_offset(pgdp, addr);
224 ptep = pte_offset_map(pmdp, addr);
225
226 set_pte(ptep, mk_pte(virt_to_page(page), dvma_prot));
227
228 i = ((addr - IOUNIT_DMA_BASE) >> PAGE_SHIFT);
229
230 iopte = iounit->page_table + i;
231 sbus_writel(MKIOPTE(__pa(page)), iopte);
232 }
233 addr += PAGE_SIZE;
234 va += PAGE_SIZE;
235 }
236 flush_cache_all();
237 flush_tlb_all();
238
239 return 0;
240 }
241
iounit_unmap_dma_area(struct device * dev,unsigned long addr,int len)242 static void iounit_unmap_dma_area(struct device *dev, unsigned long addr, int len)
243 {
244 /* XXX Somebody please fill this in */
245 }
246 #endif
247
248 static const struct sparc32_dma_ops iounit_dma_ops = {
249 .get_scsi_one = iounit_get_scsi_one,
250 .get_scsi_sgl = iounit_get_scsi_sgl,
251 .release_scsi_one = iounit_release_scsi_one,
252 .release_scsi_sgl = iounit_release_scsi_sgl,
253 #ifdef CONFIG_SBUS
254 .map_dma_area = iounit_map_dma_area,
255 .unmap_dma_area = iounit_unmap_dma_area,
256 #endif
257 };
258
ld_mmu_iounit(void)259 void __init ld_mmu_iounit(void)
260 {
261 sparc32_dma_ops = &iounit_dma_ops;
262 }
263