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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/highmem.h>
14#include <linux/bitops.h>
15#include <linux/dma-mapping.h>
16#include <linux/of.h>
17#include <linux/of_device.h>
18
19#include <asm/pgalloc.h>
20#include <asm/pgtable.h>
21#include <asm/io.h>
22#include <asm/io-unit.h>
23#include <asm/mxcc.h>
24#include <asm/cacheflush.h>
25#include <asm/tlbflush.h>
26#include <asm/dma.h>
27#include <asm/oplib.h>
28
29#include "mm_32.h"
30
31
32#ifdef IOUNIT_DEBUG
33#define IOD(x) printk(x)
34#else
35#define IOD(x) do { } while (0)
36#endif
37
38#define IOPERM (IOUPTE_CACHE | IOUPTE_WRITE | IOUPTE_VALID)
39#define MKIOPTE(phys) __iopte((((phys)>>4) & IOUPTE_PAGE) | IOPERM)
40
41static void __init iounit_iommu_init(struct platform_device *op)
42{
43 struct iounit_struct *iounit;
44 iopte_t __iomem *xpt;
45 iopte_t __iomem *xptend;
46
47 iounit = kzalloc(sizeof(struct iounit_struct), GFP_ATOMIC);
48 if (!iounit) {
49 prom_printf("SUN4D: Cannot alloc iounit, halting.\n");
50 prom_halt();
51 }
52
53 iounit->limit[0] = IOUNIT_BMAP1_START;
54 iounit->limit[1] = IOUNIT_BMAP2_START;
55 iounit->limit[2] = IOUNIT_BMAPM_START;
56 iounit->limit[3] = IOUNIT_BMAPM_END;
57 iounit->rotor[1] = IOUNIT_BMAP2_START;
58 iounit->rotor[2] = IOUNIT_BMAPM_START;
59
60 xpt = of_ioremap(&op->resource[2], 0, PAGE_SIZE * 16, "XPT");
61 if (!xpt) {
62 prom_printf("SUN4D: Cannot map External Page Table.");
63 prom_halt();
64 }
65
66 op->dev.archdata.iommu = iounit;
67 iounit->page_table = xpt;
68 spin_lock_init(&iounit->lock);
69
70 xptend = iounit->page_table + (16 * PAGE_SIZE) / sizeof(iopte_t);
71 for (; xpt < xptend; xpt++)
72 sbus_writel(0, xpt);
73}
74
75static int __init iounit_init(void)
76{
77 extern void sun4d_init_sbi_irq(void);
78 struct device_node *dp;
79
80 for_each_node_by_name(dp, "sbi") {
81 struct platform_device *op = of_find_device_by_node(dp);
82
83 iounit_iommu_init(op);
84 of_propagate_archdata(op);
85 }
86
87 sun4d_init_sbi_irq();
88
89 return 0;
90}
91
92subsys_initcall(iounit_init);
93
94
95static unsigned long iounit_get_area(struct iounit_struct *iounit, unsigned long vaddr, int size)
96{
97 int i, j, k, npages;
98 unsigned long rotor, scan, limit;
99 iopte_t iopte;
100
101 npages = ((vaddr & ~PAGE_MASK) + size + (PAGE_SIZE-1)) >> PAGE_SHIFT;
102
103
104 switch (npages) {
105 case 1: i = 0x0231; break;
106 case 2: i = 0x0132; break;
107 default: i = 0x0213; break;
108 }
109
110 IOD(("iounit_get_area(%08lx,%d[%d])=", vaddr, size, npages));
111
112next: j = (i & 15);
113 rotor = iounit->rotor[j - 1];
114 limit = iounit->limit[j];
115 scan = rotor;
116nexti: scan = find_next_zero_bit(iounit->bmap, limit, scan);
117 if (scan + npages > limit) {
118 if (limit != rotor) {
119 limit = rotor;
120 scan = iounit->limit[j - 1];
121 goto nexti;
122 }
123 i >>= 4;
124 if (!(i & 15))
125 panic("iounit_get_area: Couldn't find free iopte slots for (%08lx,%d)\n", vaddr, size);
126 goto next;
127 }
128 for (k = 1, scan++; k < npages; k++)
129 if (test_bit(scan++, iounit->bmap))
130 goto nexti;
131 iounit->rotor[j - 1] = (scan < limit) ? scan : iounit->limit[j - 1];
132 scan -= npages;
133 iopte = MKIOPTE(__pa(vaddr & PAGE_MASK));
134 vaddr = IOUNIT_DMA_BASE + (scan << PAGE_SHIFT) + (vaddr & ~PAGE_MASK);
135 for (k = 0; k < npages; k++, iopte = __iopte(iopte_val(iopte) + 0x100), scan++) {
136 set_bit(scan, iounit->bmap);
137 sbus_writel(iopte_val(iopte), &iounit->page_table[scan]);
138 }
139 IOD(("%08lx\n", vaddr));
140 return vaddr;
141}
142
143static dma_addr_t iounit_map_page(struct device *dev, struct page *page,
144 unsigned long offset, size_t len, enum dma_data_direction dir,
145 unsigned long attrs)
146{
147 void *vaddr = page_address(page) + offset;
148 struct iounit_struct *iounit = dev->archdata.iommu;
149 unsigned long ret, flags;
150
151
152 if (!len || len > 256 * 1024)
153 return DMA_MAPPING_ERROR;
154
155 spin_lock_irqsave(&iounit->lock, flags);
156 ret = iounit_get_area(iounit, (unsigned long)vaddr, len);
157 spin_unlock_irqrestore(&iounit->lock, flags);
158 return ret;
159}
160
161static int iounit_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
162 enum dma_data_direction dir, unsigned long attrs)
163{
164 struct iounit_struct *iounit = dev->archdata.iommu;
165 struct scatterlist *sg;
166 unsigned long flags;
167 int i;
168
169
170 spin_lock_irqsave(&iounit->lock, flags);
171 for_each_sg(sgl, sg, nents, i) {
172 sg->dma_address = iounit_get_area(iounit, (unsigned long) sg_virt(sg), sg->length);
173 sg->dma_length = sg->length;
174 }
175 spin_unlock_irqrestore(&iounit->lock, flags);
176 return nents;
177}
178
179static void iounit_unmap_page(struct device *dev, dma_addr_t vaddr, size_t len,
180 enum dma_data_direction dir, unsigned long attrs)
181{
182 struct iounit_struct *iounit = dev->archdata.iommu;
183 unsigned long flags;
184
185 spin_lock_irqsave(&iounit->lock, flags);
186 len = ((vaddr & ~PAGE_MASK) + len + (PAGE_SIZE-1)) >> PAGE_SHIFT;
187 vaddr = (vaddr - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
188 IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr));
189 for (len += vaddr; vaddr < len; vaddr++)
190 clear_bit(vaddr, iounit->bmap);
191 spin_unlock_irqrestore(&iounit->lock, flags);
192}
193
194static void iounit_unmap_sg(struct device *dev, struct scatterlist *sgl,
195 int nents, enum dma_data_direction dir, unsigned long attrs)
196{
197 struct iounit_struct *iounit = dev->archdata.iommu;
198 unsigned long flags, vaddr, len;
199 struct scatterlist *sg;
200 int i;
201
202 spin_lock_irqsave(&iounit->lock, flags);
203 for_each_sg(sgl, sg, nents, i) {
204 len = ((sg->dma_address & ~PAGE_MASK) + sg->length + (PAGE_SIZE-1)) >> PAGE_SHIFT;
205 vaddr = (sg->dma_address - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
206 IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr));
207 for (len += vaddr; vaddr < len; vaddr++)
208 clear_bit(vaddr, iounit->bmap);
209 }
210 spin_unlock_irqrestore(&iounit->lock, flags);
211}
212
213#ifdef CONFIG_SBUS
214static void *iounit_alloc(struct device *dev, size_t len,
215 dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
216{
217 struct iounit_struct *iounit = dev->archdata.iommu;
218 unsigned long va, addr, page, end, ret;
219 pgprot_t dvma_prot;
220 iopte_t __iomem *iopte;
221
222
223 if (!len || len > 256 * 1024)
224 return NULL;
225
226 len = PAGE_ALIGN(len);
227 va = __get_free_pages(gfp | __GFP_ZERO, get_order(len));
228 if (!va)
229 return NULL;
230
231 addr = ret = sparc_dma_alloc_resource(dev, len);
232 if (!addr)
233 goto out_free_pages;
234 *dma_handle = addr;
235
236 dvma_prot = __pgprot(SRMMU_CACHE | SRMMU_ET_PTE | SRMMU_PRIV);
237 end = PAGE_ALIGN((addr + len));
238 while(addr < end) {
239 page = va;
240 {
241 pgd_t *pgdp;
242 pmd_t *pmdp;
243 pte_t *ptep;
244 long i;
245
246 pgdp = pgd_offset(&init_mm, addr);
247 pmdp = pmd_offset(pgdp, addr);
248 ptep = pte_offset_map(pmdp, addr);
249
250 set_pte(ptep, mk_pte(virt_to_page(page), dvma_prot));
251
252 i = ((addr - IOUNIT_DMA_BASE) >> PAGE_SHIFT);
253
254 iopte = iounit->page_table + i;
255 sbus_writel(iopte_val(MKIOPTE(__pa(page))), iopte);
256 }
257 addr += PAGE_SIZE;
258 va += PAGE_SIZE;
259 }
260 flush_cache_all();
261 flush_tlb_all();
262
263 return (void *)ret;
264
265out_free_pages:
266 free_pages(va, get_order(len));
267 return NULL;
268}
269
270static void iounit_free(struct device *dev, size_t size, void *cpu_addr,
271 dma_addr_t dma_addr, unsigned long attrs)
272{
273
274}
275#endif
276
277static const struct dma_map_ops iounit_dma_ops = {
278#ifdef CONFIG_SBUS
279 .alloc = iounit_alloc,
280 .free = iounit_free,
281#endif
282 .map_page = iounit_map_page,
283 .unmap_page = iounit_unmap_page,
284 .map_sg = iounit_map_sg,
285 .unmap_sg = iounit_unmap_sg,
286};
287
288void __init ld_mmu_iounit(void)
289{
290 dma_ops = &iounit_dma_ops;
291}
292
