xref: /linux/arch/sparc/mm/io-unit.c (revision 2b8232ce512105e28453f301d1510de8363bccd1)
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.
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 
15 #include <asm/scatterlist.h>
16 #include <asm/pgalloc.h>
17 #include <asm/pgtable.h>
18 #include <asm/sbus.h>
19 #include <asm/io.h>
20 #include <asm/io-unit.h>
21 #include <asm/mxcc.h>
22 #include <asm/cacheflush.h>
23 #include <asm/tlbflush.h>
24 #include <asm/dma.h>
25 #include <asm/oplib.h>
26 
27 /* #define IOUNIT_DEBUG */
28 #ifdef IOUNIT_DEBUG
29 #define IOD(x) printk(x)
30 #else
31 #define IOD(x) do { } while (0)
32 #endif
33 
34 #define IOPERM        (IOUPTE_CACHE | IOUPTE_WRITE | IOUPTE_VALID)
35 #define MKIOPTE(phys) __iopte((((phys)>>4) & IOUPTE_PAGE) | IOPERM)
36 
37 void __init
38 iounit_init(int sbi_node, int io_node, struct sbus_bus *sbus)
39 {
40 	iopte_t *xpt, *xptend;
41 	struct iounit_struct *iounit;
42 	struct linux_prom_registers iommu_promregs[PROMREG_MAX];
43 	struct resource r;
44 
45 	iounit = kzalloc(sizeof(struct iounit_struct), GFP_ATOMIC);
46 	if (!iounit) {
47 		prom_printf("SUN4D: Cannot alloc iounit, halting.\n");
48 		prom_halt();
49 	}
50 
51 	iounit->limit[0] = IOUNIT_BMAP1_START;
52 	iounit->limit[1] = IOUNIT_BMAP2_START;
53 	iounit->limit[2] = IOUNIT_BMAPM_START;
54 	iounit->limit[3] = IOUNIT_BMAPM_END;
55 	iounit->rotor[1] = IOUNIT_BMAP2_START;
56 	iounit->rotor[2] = IOUNIT_BMAPM_START;
57 
58 	xpt = NULL;
59 	if(prom_getproperty(sbi_node, "reg", (void *) iommu_promregs,
60 			    sizeof(iommu_promregs)) != -1) {
61 		prom_apply_generic_ranges(io_node, 0, iommu_promregs, 3);
62 		memset(&r, 0, sizeof(r));
63 		r.flags = iommu_promregs[2].which_io;
64 		r.start = iommu_promregs[2].phys_addr;
65 		xpt = (iopte_t *) sbus_ioremap(&r, 0, PAGE_SIZE * 16, "XPT");
66 	}
67 	if(!xpt) panic("Cannot map External Page Table.");
68 
69 	sbus->ofdev.dev.archdata.iommu = iounit;
70 	iounit->page_table = xpt;
71 	spin_lock_init(&iounit->lock);
72 
73 	for (xptend = iounit->page_table + (16 * PAGE_SIZE) / sizeof(iopte_t);
74 	     xpt < xptend;)
75 	     	iopte_val(*xpt++) = 0;
76 }
77 
78 /* One has to hold iounit->lock to call this */
79 static unsigned long iounit_get_area(struct iounit_struct *iounit, unsigned long vaddr, int size)
80 {
81 	int i, j, k, npages;
82 	unsigned long rotor, scan, limit;
83 	iopte_t iopte;
84 
85         npages = ((vaddr & ~PAGE_MASK) + size + (PAGE_SIZE-1)) >> PAGE_SHIFT;
86 
87 	/* A tiny bit of magic ingredience :) */
88 	switch (npages) {
89 	case 1: i = 0x0231; break;
90 	case 2: i = 0x0132; break;
91 	default: i = 0x0213; break;
92 	}
93 
94 	IOD(("iounit_get_area(%08lx,%d[%d])=", vaddr, size, npages));
95 
96 next:	j = (i & 15);
97 	rotor = iounit->rotor[j - 1];
98 	limit = iounit->limit[j];
99 	scan = rotor;
100 nexti:	scan = find_next_zero_bit(iounit->bmap, limit, scan);
101 	if (scan + npages > limit) {
102 		if (limit != rotor) {
103 			limit = rotor;
104 			scan = iounit->limit[j - 1];
105 			goto nexti;
106 		}
107 		i >>= 4;
108 		if (!(i & 15))
109 			panic("iounit_get_area: Couldn't find free iopte slots for (%08lx,%d)\n", vaddr, size);
110 		goto next;
111 	}
112 	for (k = 1, scan++; k < npages; k++)
113 		if (test_bit(scan++, iounit->bmap))
114 			goto nexti;
115 	iounit->rotor[j - 1] = (scan < limit) ? scan : iounit->limit[j - 1];
116 	scan -= npages;
117 	iopte = MKIOPTE(__pa(vaddr & PAGE_MASK));
118 	vaddr = IOUNIT_DMA_BASE + (scan << PAGE_SHIFT) + (vaddr & ~PAGE_MASK);
119 	for (k = 0; k < npages; k++, iopte = __iopte(iopte_val(iopte) + 0x100), scan++) {
120 		set_bit(scan, iounit->bmap);
121 		iounit->page_table[scan] = iopte;
122 	}
123 	IOD(("%08lx\n", vaddr));
124 	return vaddr;
125 }
126 
127 static __u32 iounit_get_scsi_one(char *vaddr, unsigned long len, struct sbus_bus *sbus)
128 {
129 	unsigned long ret, flags;
130 	struct iounit_struct *iounit = sbus->ofdev.dev.archdata.iommu;
131 
132 	spin_lock_irqsave(&iounit->lock, flags);
133 	ret = iounit_get_area(iounit, (unsigned long)vaddr, len);
134 	spin_unlock_irqrestore(&iounit->lock, flags);
135 	return ret;
136 }
137 
138 static void iounit_get_scsi_sgl(struct scatterlist *sg, int sz, struct sbus_bus *sbus)
139 {
140 	unsigned long flags;
141 	struct iounit_struct *iounit = sbus->ofdev.dev.archdata.iommu;
142 
143 	/* FIXME: Cache some resolved pages - often several sg entries are to the same page */
144 	spin_lock_irqsave(&iounit->lock, flags);
145 	while (sz != 0) {
146 		--sz;
147 		sg[sz].dvma_address = iounit_get_area(iounit, (unsigned long)page_address(sg[sz].page) + sg[sz].offset, sg[sz].length);
148 		sg[sz].dvma_length = sg[sz].length;
149 	}
150 	spin_unlock_irqrestore(&iounit->lock, flags);
151 }
152 
153 static void iounit_release_scsi_one(__u32 vaddr, unsigned long len, struct sbus_bus *sbus)
154 {
155 	unsigned long flags;
156 	struct iounit_struct *iounit = sbus->ofdev.dev.archdata.iommu;
157 
158 	spin_lock_irqsave(&iounit->lock, flags);
159 	len = ((vaddr & ~PAGE_MASK) + len + (PAGE_SIZE-1)) >> PAGE_SHIFT;
160 	vaddr = (vaddr - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
161 	IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr));
162 	for (len += vaddr; vaddr < len; vaddr++)
163 		clear_bit(vaddr, iounit->bmap);
164 	spin_unlock_irqrestore(&iounit->lock, flags);
165 }
166 
167 static void iounit_release_scsi_sgl(struct scatterlist *sg, int sz, struct sbus_bus *sbus)
168 {
169 	unsigned long flags;
170 	unsigned long vaddr, len;
171 	struct iounit_struct *iounit = sbus->ofdev.dev.archdata.iommu;
172 
173 	spin_lock_irqsave(&iounit->lock, flags);
174 	while (sz != 0) {
175 		--sz;
176 		len = ((sg[sz].dvma_address & ~PAGE_MASK) + sg[sz].length + (PAGE_SIZE-1)) >> PAGE_SHIFT;
177 		vaddr = (sg[sz].dvma_address - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
178 		IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr));
179 		for (len += vaddr; vaddr < len; vaddr++)
180 			clear_bit(vaddr, iounit->bmap);
181 	}
182 	spin_unlock_irqrestore(&iounit->lock, flags);
183 }
184 
185 #ifdef CONFIG_SBUS
186 static int iounit_map_dma_area(dma_addr_t *pba, unsigned long va, __u32 addr, int len)
187 {
188 	unsigned long page, end;
189 	pgprot_t dvma_prot;
190 	iopte_t *iopte;
191 	struct sbus_bus *sbus;
192 
193 	*pba = addr;
194 
195 	dvma_prot = __pgprot(SRMMU_CACHE | SRMMU_ET_PTE | SRMMU_PRIV);
196 	end = PAGE_ALIGN((addr + len));
197 	while(addr < end) {
198 		page = va;
199 		{
200 			pgd_t *pgdp;
201 			pmd_t *pmdp;
202 			pte_t *ptep;
203 			long i;
204 
205 			pgdp = pgd_offset(&init_mm, addr);
206 			pmdp = pmd_offset(pgdp, addr);
207 			ptep = pte_offset_map(pmdp, addr);
208 
209 			set_pte(ptep, mk_pte(virt_to_page(page), dvma_prot));
210 
211 			i = ((addr - IOUNIT_DMA_BASE) >> PAGE_SHIFT);
212 
213 			for_each_sbus(sbus) {
214 				struct iounit_struct *iounit = sbus->ofdev.dev.archdata.iommu;
215 
216 				iopte = (iopte_t *)(iounit->page_table + i);
217 				*iopte = MKIOPTE(__pa(page));
218 			}
219 		}
220 		addr += PAGE_SIZE;
221 		va += PAGE_SIZE;
222 	}
223 	flush_cache_all();
224 	flush_tlb_all();
225 
226 	return 0;
227 }
228 
229 static void iounit_unmap_dma_area(unsigned long addr, int len)
230 {
231 	/* XXX Somebody please fill this in */
232 }
233 
234 /* XXX We do not pass sbus device here, bad. */
235 static struct page *iounit_translate_dvma(unsigned long addr)
236 {
237 	struct sbus_bus *sbus = sbus_root;	/* They are all the same */
238 	struct iounit_struct *iounit = sbus->ofdev.dev.archdata.iommu;
239 	int i;
240 	iopte_t *iopte;
241 
242 	i = ((addr - IOUNIT_DMA_BASE) >> PAGE_SHIFT);
243 	iopte = (iopte_t *)(iounit->page_table + i);
244 	return pfn_to_page(iopte_val(*iopte) >> (PAGE_SHIFT-4)); /* XXX sun4d guru, help */
245 }
246 #endif
247 
248 static char *iounit_lockarea(char *vaddr, unsigned long len)
249 {
250 /* FIXME: Write this */
251 	return vaddr;
252 }
253 
254 static void iounit_unlockarea(char *vaddr, unsigned long len)
255 {
256 /* FIXME: Write this */
257 }
258 
259 void __init ld_mmu_iounit(void)
260 {
261 	BTFIXUPSET_CALL(mmu_lockarea, iounit_lockarea, BTFIXUPCALL_RETO0);
262 	BTFIXUPSET_CALL(mmu_unlockarea, iounit_unlockarea, BTFIXUPCALL_NOP);
263 
264 	BTFIXUPSET_CALL(mmu_get_scsi_one, iounit_get_scsi_one, BTFIXUPCALL_NORM);
265 	BTFIXUPSET_CALL(mmu_get_scsi_sgl, iounit_get_scsi_sgl, BTFIXUPCALL_NORM);
266 	BTFIXUPSET_CALL(mmu_release_scsi_one, iounit_release_scsi_one, BTFIXUPCALL_NORM);
267 	BTFIXUPSET_CALL(mmu_release_scsi_sgl, iounit_release_scsi_sgl, BTFIXUPCALL_NORM);
268 
269 #ifdef CONFIG_SBUS
270 	BTFIXUPSET_CALL(mmu_map_dma_area, iounit_map_dma_area, BTFIXUPCALL_NORM);
271 	BTFIXUPSET_CALL(mmu_unmap_dma_area, iounit_unmap_dma_area, BTFIXUPCALL_NORM);
272 	BTFIXUPSET_CALL(mmu_translate_dvma, iounit_translate_dvma, BTFIXUPCALL_NORM);
273 #endif
274 }
275 
276 __u32 iounit_map_dma_init(struct sbus_bus *sbus, int size)
277 {
278 	int i, j, k, npages;
279 	unsigned long rotor, scan, limit;
280 	unsigned long flags;
281 	__u32 ret;
282 	struct iounit_struct *iounit = sbus->ofdev.dev.archdata.iommu;
283 
284         npages = (size + (PAGE_SIZE-1)) >> PAGE_SHIFT;
285 	i = 0x0213;
286 	spin_lock_irqsave(&iounit->lock, flags);
287 next:	j = (i & 15);
288 	rotor = iounit->rotor[j - 1];
289 	limit = iounit->limit[j];
290 	scan = rotor;
291 nexti:	scan = find_next_zero_bit(iounit->bmap, limit, scan);
292 	if (scan + npages > limit) {
293 		if (limit != rotor) {
294 			limit = rotor;
295 			scan = iounit->limit[j - 1];
296 			goto nexti;
297 		}
298 		i >>= 4;
299 		if (!(i & 15))
300 			panic("iounit_map_dma_init: Couldn't find free iopte slots for %d bytes\n", size);
301 		goto next;
302 	}
303 	for (k = 1, scan++; k < npages; k++)
304 		if (test_bit(scan++, iounit->bmap))
305 			goto nexti;
306 	iounit->rotor[j - 1] = (scan < limit) ? scan : iounit->limit[j - 1];
307 	scan -= npages;
308 	ret = IOUNIT_DMA_BASE + (scan << PAGE_SHIFT);
309 	for (k = 0; k < npages; k++, scan++)
310 		set_bit(scan, iounit->bmap);
311 	spin_unlock_irqrestore(&iounit->lock, flags);
312 	return ret;
313 }
314 
315 __u32 iounit_map_dma_page(__u32 vaddr, void *addr, struct sbus_bus *sbus)
316 {
317 	int scan = (vaddr - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
318 	struct iounit_struct *iounit = sbus->ofdev.dev.archdata.iommu;
319 
320 	iounit->page_table[scan] = MKIOPTE(__pa(((unsigned long)addr) & PAGE_MASK));
321 	return vaddr + (((unsigned long)addr) & ~PAGE_MASK);
322 }
323