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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/bitops.h>
14#include <linux/dma-mapping.h>
15#include <linux/of.h>
16#include <linux/of_device.h>
17
18#include <asm/io.h>
19#include <asm/io-unit.h>
20#include <asm/mxcc.h>
21#include <asm/cacheflush.h>
22#include <asm/tlbflush.h>
23#include <asm/dma.h>
24#include <asm/oplib.h>
25
26#include "mm_32.h"
27
28
29#ifdef IOUNIT_DEBUG
30#define IOD(x) printk(x)
31#else
32#define IOD(x) do { } while (0)
33#endif
34
35#define IOPERM (IOUPTE_CACHE | IOUPTE_WRITE | IOUPTE_VALID)
36#define MKIOPTE(phys) __iopte((((phys)>>4) & IOUPTE_PAGE) | IOPERM)
37
38static const struct dma_map_ops iounit_dma_ops;
39
40static 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 op->dev.dma_ops = &iounit_dma_ops;
74}
75
76static int __init iounit_init(void)
77{
78 extern void sun4d_init_sbi_irq(void);
79 struct device_node *dp;
80
81 for_each_node_by_name(dp, "sbi") {
82 struct platform_device *op = of_find_device_by_node(dp);
83
84 iounit_iommu_init(op);
85 of_propagate_archdata(op);
86 }
87
88 sun4d_init_sbi_irq();
89
90 return 0;
91}
92
93subsys_initcall(iounit_init);
94
95
96static unsigned long iounit_get_area(struct iounit_struct *iounit, unsigned long vaddr, int size)
97{
98 int i, j, k, npages;
99 unsigned long rotor, scan, limit;
100 iopte_t iopte;
101
102 npages = ((vaddr & ~PAGE_MASK) + size + (PAGE_SIZE-1)) >> PAGE_SHIFT;
103
104
105 switch (npages) {
106 case 1: i = 0x0231; break;
107 case 2: i = 0x0132; break;
108 default: i = 0x0213; break;
109 }
110
111 IOD(("iounit_get_area(%08lx,%d[%d])=", vaddr, size, npages));
112
113next: j = (i & 15);
114 rotor = iounit->rotor[j - 1];
115 limit = iounit->limit[j];
116 scan = rotor;
117nexti: scan = find_next_zero_bit(iounit->bmap, limit, scan);
118 if (scan + npages > limit) {
119 if (limit != rotor) {
120 limit = rotor;
121 scan = iounit->limit[j - 1];
122 goto nexti;
123 }
124 i >>= 4;
125 if (!(i & 15))
126 panic("iounit_get_area: Couldn't find free iopte slots for (%08lx,%d)\n", vaddr, size);
127 goto next;
128 }
129 for (k = 1, scan++; k < npages; k++)
130 if (test_bit(scan++, iounit->bmap))
131 goto nexti;
132 iounit->rotor[j - 1] = (scan < limit) ? scan : iounit->limit[j - 1];
133 scan -= npages;
134 iopte = MKIOPTE(__pa(vaddr & PAGE_MASK));
135 vaddr = IOUNIT_DMA_BASE + (scan << PAGE_SHIFT) + (vaddr & ~PAGE_MASK);
136 for (k = 0; k < npages; k++, iopte = __iopte(iopte_val(iopte) + 0x100), scan++) {
137 set_bit(scan, iounit->bmap);
138 sbus_writel(iopte_val(iopte), &iounit->page_table[scan]);
139 }
140 IOD(("%08lx\n", vaddr));
141 return vaddr;
142}
143
144static dma_addr_t iounit_map_page(struct device *dev, struct page *page,
145 unsigned long offset, size_t len, enum dma_data_direction dir,
146 unsigned long attrs)
147{
148 void *vaddr = page_address(page) + offset;
149 struct iounit_struct *iounit = dev->archdata.iommu;
150 unsigned long ret, flags;
151
152
153 if (!len || len > 256 * 1024)
154 return DMA_MAPPING_ERROR;
155
156 spin_lock_irqsave(&iounit->lock, flags);
157 ret = iounit_get_area(iounit, (unsigned long)vaddr, len);
158 spin_unlock_irqrestore(&iounit->lock, flags);
159 return ret;
160}
161
162static int iounit_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
163 enum dma_data_direction dir, unsigned long attrs)
164{
165 struct iounit_struct *iounit = dev->archdata.iommu;
166 struct scatterlist *sg;
167 unsigned long flags;
168 int i;
169
170
171 spin_lock_irqsave(&iounit->lock, flags);
172 for_each_sg(sgl, sg, nents, i) {
173 sg->dma_address = iounit_get_area(iounit, (unsigned long) sg_virt(sg), sg->length);
174 sg->dma_length = sg->length;
175 }
176 spin_unlock_irqrestore(&iounit->lock, flags);
177 return nents;
178}
179
180static void iounit_unmap_page(struct device *dev, dma_addr_t vaddr, size_t len,
181 enum dma_data_direction dir, unsigned long attrs)
182{
183 struct iounit_struct *iounit = dev->archdata.iommu;
184 unsigned long flags;
185
186 spin_lock_irqsave(&iounit->lock, flags);
187 len = ((vaddr & ~PAGE_MASK) + len + (PAGE_SIZE-1)) >> PAGE_SHIFT;
188 vaddr = (vaddr - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
189 IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr));
190 for (len += vaddr; vaddr < len; vaddr++)
191 clear_bit(vaddr, iounit->bmap);
192 spin_unlock_irqrestore(&iounit->lock, flags);
193}
194
195static void iounit_unmap_sg(struct device *dev, struct scatterlist *sgl,
196 int nents, enum dma_data_direction dir, unsigned long attrs)
197{
198 struct iounit_struct *iounit = dev->archdata.iommu;
199 unsigned long flags, vaddr, len;
200 struct scatterlist *sg;
201 int i;
202
203 spin_lock_irqsave(&iounit->lock, flags);
204 for_each_sg(sgl, sg, nents, i) {
205 len = ((sg->dma_address & ~PAGE_MASK) + sg->length + (PAGE_SIZE-1)) >> PAGE_SHIFT;
206 vaddr = (sg->dma_address - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
207 IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr));
208 for (len += vaddr; vaddr < len; vaddr++)
209 clear_bit(vaddr, iounit->bmap);
210 }
211 spin_unlock_irqrestore(&iounit->lock, flags);
212}
213
214#ifdef CONFIG_SBUS
215static void *iounit_alloc(struct device *dev, size_t len,
216 dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
217{
218 struct iounit_struct *iounit = dev->archdata.iommu;
219 unsigned long va, addr, page, end, ret;
220 pgprot_t dvma_prot;
221 iopte_t __iomem *iopte;
222
223
224 if (!len || len > 256 * 1024)
225 return NULL;
226
227 len = PAGE_ALIGN(len);
228 va = __get_free_pages(gfp | __GFP_ZERO, get_order(len));
229 if (!va)
230 return NULL;
231
232 addr = ret = sparc_dma_alloc_resource(dev, len);
233 if (!addr)
234 goto out_free_pages;
235 *dma_handle = addr;
236
237 dvma_prot = __pgprot(SRMMU_CACHE | SRMMU_ET_PTE | SRMMU_PRIV);
238 end = PAGE_ALIGN((addr + len));
239 while(addr < end) {
240 page = va;
241 {
242 pmd_t *pmdp;
243 pte_t *ptep;
244 long i;
245
246 pmdp = pmd_off_k(addr);
247 ptep = pte_offset_map(pmdp, addr);
248
249 set_pte(ptep, mk_pte(virt_to_page(page), dvma_prot));
250
251 i = ((addr - IOUNIT_DMA_BASE) >> PAGE_SHIFT);
252
253 iopte = iounit->page_table + i;
254 sbus_writel(iopte_val(MKIOPTE(__pa(page))), iopte);
255 }
256 addr += PAGE_SIZE;
257 va += PAGE_SIZE;
258 }
259 flush_cache_all();
260 flush_tlb_all();
261
262 return (void *)ret;
263
264out_free_pages:
265 free_pages(va, get_order(len));
266 return NULL;
267}
268
269static void iounit_free(struct device *dev, size_t size, void *cpu_addr,
270 dma_addr_t dma_addr, unsigned long attrs)
271{
272
273}
274#endif
275
276static const struct dma_map_ops iounit_dma_ops = {
277#ifdef CONFIG_SBUS
278 .alloc = iounit_alloc,
279 .free = iounit_free,
280#endif
281 .map_page = iounit_map_page,
282 .unmap_page = iounit_unmap_page,
283 .map_sg = iounit_map_sg,
284 .unmap_sg = iounit_unmap_sg,
285};
286
