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  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * ioport.c:  Simple io mapping allocator.
  4 *
  5 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
  6 * Copyright (C) 1995 Miguel de Icaza (miguel@nuclecu.unam.mx)
  7 *
  8 * 1996: sparc_free_io, 1999: ioremap()/iounmap() by Pete Zaitcev.
  9 *
 10 * 2000/01/29
 11 * <rth> zait: as long as pci_alloc_consistent produces something addressable, 
 12 *	things are ok.
 13 * <zaitcev> rth: no, it is relevant, because get_free_pages returns you a
 14 *	pointer into the big page mapping
 15 * <rth> zait: so what?
 16 * <rth> zait: remap_it_my_way(virt_to_phys(get_free_page()))
 17 * <zaitcev> Hmm
 18 * <zaitcev> Suppose I did this remap_it_my_way(virt_to_phys(get_free_page())).
 19 *	So far so good.
 20 * <zaitcev> Now, driver calls pci_free_consistent(with result of
 21 *	remap_it_my_way()).
 22 * <zaitcev> How do you find the address to pass to free_pages()?
 23 * <rth> zait: walk the page tables?  It's only two or three level after all.
 24 * <rth> zait: you have to walk them anyway to remove the mapping.
 25 * <zaitcev> Hmm
 26 * <zaitcev> Sounds reasonable
 27 */
 28
 29#include <linux/module.h>
 30#include <linux/sched.h>
 31#include <linux/kernel.h>
 32#include <linux/errno.h>
 33#include <linux/types.h>
 34#include <linux/ioport.h>
 35#include <linux/mm.h>
 36#include <linux/slab.h>
 37#include <linux/pci.h>		/* struct pci_dev */
 38#include <linux/proc_fs.h>
 39#include <linux/seq_file.h>
 40#include <linux/scatterlist.h>
 
 41#include <linux/of_device.h>
 42
 43#include <asm/io.h>
 44#include <asm/vaddrs.h>
 45#include <asm/oplib.h>
 46#include <asm/prom.h>
 47#include <asm/page.h>
 48#include <asm/pgalloc.h>
 49#include <asm/dma.h>
 50#include <asm/iommu.h>
 51#include <asm/io-unit.h>
 52#include <asm/leon.h>
 53
 54const struct sparc32_dma_ops *sparc32_dma_ops;
 55
 56/* This function must make sure that caches and memory are coherent after DMA
 57 * On LEON systems without cache snooping it flushes the entire D-CACHE.
 58 */
 59static inline void dma_make_coherent(unsigned long pa, unsigned long len)
 60{
 61	if (sparc_cpu_model == sparc_leon) {
 62		if (!sparc_leon3_snooping_enabled())
 63			leon_flush_dcache_all();
 64	}
 65}
 66
 67static void __iomem *_sparc_ioremap(struct resource *res, u32 bus, u32 pa, int sz);
 68static void __iomem *_sparc_alloc_io(unsigned int busno, unsigned long phys,
 69    unsigned long size, char *name);
 70static void _sparc_free_io(struct resource *res);
 71
 72static void register_proc_sparc_ioport(void);
 73
 74/* This points to the next to use virtual memory for DVMA mappings */
 75static struct resource _sparc_dvma = {
 76	.name = "sparc_dvma", .start = DVMA_VADDR, .end = DVMA_END - 1
 77};
 78/* This points to the start of I/O mappings, cluable from outside. */
 79/*ext*/ struct resource sparc_iomap = {
 80	.name = "sparc_iomap", .start = IOBASE_VADDR, .end = IOBASE_END - 1
 81};
 82
 83/*
 84 * Our mini-allocator...
 85 * Boy this is gross! We need it because we must map I/O for
 86 * timers and interrupt controller before the kmalloc is available.
 87 */
 88
 89#define XNMLN  15
 90#define XNRES  10	/* SS-10 uses 8 */
 91
 92struct xresource {
 93	struct resource xres;	/* Must be first */
 94	int xflag;		/* 1 == used */
 95	char xname[XNMLN+1];
 96};
 97
 98static struct xresource xresv[XNRES];
 99
100static struct xresource *xres_alloc(void) {
101	struct xresource *xrp;
102	int n;
103
104	xrp = xresv;
105	for (n = 0; n < XNRES; n++) {
106		if (xrp->xflag == 0) {
107			xrp->xflag = 1;
108			return xrp;
109		}
110		xrp++;
111	}
112	return NULL;
113}
114
115static void xres_free(struct xresource *xrp) {
116	xrp->xflag = 0;
117}
118
119/*
120 * These are typically used in PCI drivers
121 * which are trying to be cross-platform.
122 *
123 * Bus type is always zero on IIep.
124 */
125void __iomem *ioremap(phys_addr_t offset, size_t size)
126{
127	char name[14];
128
129	sprintf(name, "phys_%08x", (u32)offset);
130	return _sparc_alloc_io(0, (unsigned long)offset, size, name);
131}
132EXPORT_SYMBOL(ioremap);
133
134/*
135 * Complementary to ioremap().
136 */
137void iounmap(volatile void __iomem *virtual)
138{
139	unsigned long vaddr = (unsigned long) virtual & PAGE_MASK;
140	struct resource *res;
141
142	/*
143	 * XXX Too slow. Can have 8192 DVMA pages on sun4m in the worst case.
144	 * This probably warrants some sort of hashing.
145	*/
146	if ((res = lookup_resource(&sparc_iomap, vaddr)) == NULL) {
147		printk("free_io/iounmap: cannot free %lx\n", vaddr);
148		return;
149	}
150	_sparc_free_io(res);
151
152	if ((char *)res >= (char*)xresv && (char *)res < (char *)&xresv[XNRES]) {
153		xres_free((struct xresource *)res);
154	} else {
155		kfree(res);
156	}
157}
158EXPORT_SYMBOL(iounmap);
159
160void __iomem *of_ioremap(struct resource *res, unsigned long offset,
161			 unsigned long size, char *name)
162{
163	return _sparc_alloc_io(res->flags & 0xF,
164			       res->start + offset,
165			       size, name);
166}
167EXPORT_SYMBOL(of_ioremap);
168
169void of_iounmap(struct resource *res, void __iomem *base, unsigned long size)
170{
171	iounmap(base);
172}
173EXPORT_SYMBOL(of_iounmap);
174
175/*
176 * Meat of mapping
177 */
178static void __iomem *_sparc_alloc_io(unsigned int busno, unsigned long phys,
179    unsigned long size, char *name)
180{
181	static int printed_full;
182	struct xresource *xres;
183	struct resource *res;
184	char *tack;
185	int tlen;
186	void __iomem *va;	/* P3 diag */
187
188	if (name == NULL) name = "???";
189
190	if ((xres = xres_alloc()) != NULL) {
191		tack = xres->xname;
192		res = &xres->xres;
193	} else {
194		if (!printed_full) {
195			printk("ioremap: done with statics, switching to malloc\n");
196			printed_full = 1;
197		}
198		tlen = strlen(name);
199		tack = kmalloc(sizeof (struct resource) + tlen + 1, GFP_KERNEL);
200		if (tack == NULL) return NULL;
201		memset(tack, 0, sizeof(struct resource));
202		res = (struct resource *) tack;
203		tack += sizeof (struct resource);
204	}
205
206	strlcpy(tack, name, XNMLN+1);
207	res->name = tack;
208
209	va = _sparc_ioremap(res, busno, phys, size);
210	/* printk("ioremap(0x%x:%08lx[0x%lx])=%p\n", busno, phys, size, va); */ /* P3 diag */
211	return va;
212}
213
214/*
215 */
216static void __iomem *
217_sparc_ioremap(struct resource *res, u32 bus, u32 pa, int sz)
218{
219	unsigned long offset = ((unsigned long) pa) & (~PAGE_MASK);
220
221	if (allocate_resource(&sparc_iomap, res,
222	    (offset + sz + PAGE_SIZE-1) & PAGE_MASK,
223	    sparc_iomap.start, sparc_iomap.end, PAGE_SIZE, NULL, NULL) != 0) {
224		/* Usually we cannot see printks in this case. */
225		prom_printf("alloc_io_res(%s): cannot occupy\n",
226		    (res->name != NULL)? res->name: "???");
227		prom_halt();
228	}
229
230	pa &= PAGE_MASK;
231	srmmu_mapiorange(bus, pa, res->start, resource_size(res));
232
233	return (void __iomem *)(unsigned long)(res->start + offset);
234}
235
236/*
237 * Complementary to _sparc_ioremap().
238 */
239static void _sparc_free_io(struct resource *res)
240{
241	unsigned long plen;
242
243	plen = resource_size(res);
244	BUG_ON((plen & (PAGE_SIZE-1)) != 0);
245	srmmu_unmapiorange(res->start, plen);
246	release_resource(res);
247}
248
249#ifdef CONFIG_SBUS
250
251void sbus_set_sbus64(struct device *dev, int x)
252{
253	printk("sbus_set_sbus64: unsupported\n");
254}
255EXPORT_SYMBOL(sbus_set_sbus64);
256
257/*
258 * Allocate a chunk of memory suitable for DMA.
259 * Typically devices use them for control blocks.
260 * CPU may access them without any explicit flushing.
261 */
262static void *sbus_alloc_coherent(struct device *dev, size_t len,
263				 dma_addr_t *dma_addrp, gfp_t gfp,
264				 unsigned long attrs)
265{
266	struct platform_device *op = to_platform_device(dev);
267	unsigned long len_total = PAGE_ALIGN(len);
268	unsigned long va;
269	struct resource *res;
270	int order;
271
272	/* XXX why are some lengths signed, others unsigned? */
273	if (len <= 0) {
274		return NULL;
275	}
276	/* XXX So what is maxphys for us and how do drivers know it? */
277	if (len > 256*1024) {			/* __get_free_pages() limit */
278		return NULL;
279	}
280
281	order = get_order(len_total);
282	va = __get_free_pages(gfp, order);
283	if (va == 0)
284		goto err_nopages;
285
286	if ((res = kzalloc(sizeof(struct resource), GFP_KERNEL)) == NULL)
287		goto err_nomem;
288
289	if (allocate_resource(&_sparc_dvma, res, len_total,
290	    _sparc_dvma.start, _sparc_dvma.end, PAGE_SIZE, NULL, NULL) != 0) {
291		printk("sbus_alloc_consistent: cannot occupy 0x%lx", len_total);
292		goto err_nova;
293	}
294
295	// XXX The sbus_map_dma_area does this for us below, see comments.
296	// srmmu_mapiorange(0, virt_to_phys(va), res->start, len_total);
297	/*
298	 * XXX That's where sdev would be used. Currently we load
299	 * all iommu tables with the same translations.
300	 */
301	if (sbus_map_dma_area(dev, dma_addrp, va, res->start, len_total) != 0)
302		goto err_noiommu;
303
304	res->name = op->dev.of_node->name;
305
306	return (void *)(unsigned long)res->start;
307
308err_noiommu:
309	release_resource(res);
310err_nova:
311	kfree(res);
312err_nomem:
313	free_pages(va, order);
314err_nopages:
315	return NULL;
316}
317
318static void sbus_free_coherent(struct device *dev, size_t n, void *p,
319			       dma_addr_t ba, unsigned long attrs)
320{
 
321	struct resource *res;
322	struct page *pgv;
323
324	if ((res = lookup_resource(&_sparc_dvma,
325	    (unsigned long)p)) == NULL) {
326		printk("sbus_free_consistent: cannot free %p\n", p);
327		return;
328	}
329
330	if (((unsigned long)p & (PAGE_SIZE-1)) != 0) {
331		printk("sbus_free_consistent: unaligned va %p\n", p);
332		return;
333	}
334
335	n = PAGE_ALIGN(n);
336	if (resource_size(res) != n) {
337		printk("sbus_free_consistent: region 0x%lx asked 0x%zx\n",
338		    (long)resource_size(res), n);
339		return;
 
 
 
 
 
 
340	}
341
342	release_resource(res);
343	kfree(res);
344
345	pgv = virt_to_page(p);
346	sbus_unmap_dma_area(dev, ba, n);
347
348	__free_pages(pgv, get_order(n));
349}
350
351/*
352 * Map a chunk of memory so that devices can see it.
353 * CPU view of this memory may be inconsistent with
354 * a device view and explicit flushing is necessary.
355 */
356static dma_addr_t sbus_map_page(struct device *dev, struct page *page,
357				unsigned long offset, size_t len,
358				enum dma_data_direction dir,
359				unsigned long attrs)
360{
361	void *va = page_address(page) + offset;
362
363	/* XXX why are some lengths signed, others unsigned? */
364	if (len <= 0) {
365		return 0;
366	}
367	/* XXX So what is maxphys for us and how do drivers know it? */
368	if (len > 256*1024) {			/* __get_free_pages() limit */
369		return 0;
370	}
371	return mmu_get_scsi_one(dev, va, len);
372}
373
374static void sbus_unmap_page(struct device *dev, dma_addr_t ba, size_t n,
375			    enum dma_data_direction dir, unsigned long attrs)
376{
377	mmu_release_scsi_one(dev, ba, n);
378}
379
380static int sbus_map_sg(struct device *dev, struct scatterlist *sg, int n,
381		       enum dma_data_direction dir, unsigned long attrs)
382{
383	mmu_get_scsi_sgl(dev, sg, n);
384	return n;
385}
386
387static void sbus_unmap_sg(struct device *dev, struct scatterlist *sg, int n,
388			  enum dma_data_direction dir, unsigned long attrs)
389{
390	mmu_release_scsi_sgl(dev, sg, n);
391}
392
393static void sbus_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
394				 int n,	enum dma_data_direction dir)
395{
396	BUG();
397}
398
399static void sbus_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
400				    int n, enum dma_data_direction dir)
401{
402	BUG();
403}
404
405static int sbus_dma_supported(struct device *dev, u64 mask)
406{
407	return 0;
408}
409
410static const struct dma_map_ops sbus_dma_ops = {
411	.alloc			= sbus_alloc_coherent,
412	.free			= sbus_free_coherent,
413	.map_page		= sbus_map_page,
414	.unmap_page		= sbus_unmap_page,
415	.map_sg			= sbus_map_sg,
416	.unmap_sg		= sbus_unmap_sg,
417	.sync_sg_for_cpu	= sbus_sync_sg_for_cpu,
418	.sync_sg_for_device	= sbus_sync_sg_for_device,
419	.dma_supported		= sbus_dma_supported,
420};
421
422static int __init sparc_register_ioport(void)
423{
424	register_proc_sparc_ioport();
425
426	return 0;
427}
428
429arch_initcall(sparc_register_ioport);
430
431#endif /* CONFIG_SBUS */
432
433
434/* Allocate and map kernel buffer using consistent mode DMA for a device.
435 * hwdev should be valid struct pci_dev pointer for PCI devices.
436 */
437static void *pci32_alloc_coherent(struct device *dev, size_t len,
438				  dma_addr_t *pba, gfp_t gfp,
439				  unsigned long attrs)
440{
441	unsigned long len_total = PAGE_ALIGN(len);
442	void *va;
443	struct resource *res;
444	int order;
445
446	if (len == 0) {
447		return NULL;
448	}
449	if (len > 256*1024) {			/* __get_free_pages() limit */
450		return NULL;
451	}
452
453	order = get_order(len_total);
454	va = (void *) __get_free_pages(gfp, order);
455	if (va == NULL) {
456		printk("pci_alloc_consistent: no %ld pages\n", len_total>>PAGE_SHIFT);
457		goto err_nopages;
458	}
459
460	if ((res = kzalloc(sizeof(struct resource), GFP_KERNEL)) == NULL) {
461		printk("pci_alloc_consistent: no core\n");
462		goto err_nomem;
463	}
464
465	if (allocate_resource(&_sparc_dvma, res, len_total,
466	    _sparc_dvma.start, _sparc_dvma.end, PAGE_SIZE, NULL, NULL) != 0) {
467		printk("pci_alloc_consistent: cannot occupy 0x%lx", len_total);
468		goto err_nova;
469	}
470	srmmu_mapiorange(0, virt_to_phys(va), res->start, len_total);
471
472	*pba = virt_to_phys(va); /* equals virt_to_bus (R.I.P.) for us. */
473	return (void *) res->start;
474
475err_nova:
476	kfree(res);
477err_nomem:
478	free_pages((unsigned long)va, order);
479err_nopages:
480	return NULL;
481}
482
483/* Free and unmap a consistent DMA buffer.
484 * cpu_addr is what was returned from pci_alloc_consistent,
485 * size must be the same as what as passed into pci_alloc_consistent,
486 * and likewise dma_addr must be the same as what *dma_addrp was set to.
487 *
488 * References to the memory and mappings associated with cpu_addr/dma_addr
489 * past this call are illegal.
490 */
491static void pci32_free_coherent(struct device *dev, size_t n, void *p,
492				dma_addr_t ba, unsigned long attrs)
493{
494	struct resource *res;
495
496	if ((res = lookup_resource(&_sparc_dvma,
497	    (unsigned long)p)) == NULL) {
498		printk("pci_free_consistent: cannot free %p\n", p);
499		return;
500	}
501
502	if (((unsigned long)p & (PAGE_SIZE-1)) != 0) {
503		printk("pci_free_consistent: unaligned va %p\n", p);
504		return;
505	}
506
507	n = PAGE_ALIGN(n);
508	if (resource_size(res) != n) {
509		printk("pci_free_consistent: region 0x%lx asked 0x%lx\n",
510		    (long)resource_size(res), (long)n);
511		return;
512	}
513
514	dma_make_coherent(ba, n);
515	srmmu_unmapiorange((unsigned long)p, n);
516
517	release_resource(res);
518	kfree(res);
519	free_pages((unsigned long)phys_to_virt(ba), get_order(n));
520}
521
522/*
523 * Same as pci_map_single, but with pages.
524 */
525static dma_addr_t pci32_map_page(struct device *dev, struct page *page,
526				 unsigned long offset, size_t size,
527				 enum dma_data_direction dir,
528				 unsigned long attrs)
529{
530	/* IIep is write-through, not flushing. */
531	return page_to_phys(page) + offset;
532}
533
534static void pci32_unmap_page(struct device *dev, dma_addr_t ba, size_t size,
535			     enum dma_data_direction dir, unsigned long attrs)
536{
537	if (dir != PCI_DMA_TODEVICE && !(attrs & DMA_ATTR_SKIP_CPU_SYNC))
538		dma_make_coherent(ba, PAGE_ALIGN(size));
539}
540
541/* Map a set of buffers described by scatterlist in streaming
542 * mode for DMA.  This is the scatter-gather version of the
543 * above pci_map_single interface.  Here the scatter gather list
544 * elements are each tagged with the appropriate dma address
545 * and length.  They are obtained via sg_dma_{address,length}(SG).
546 *
547 * NOTE: An implementation may be able to use a smaller number of
548 *       DMA address/length pairs than there are SG table elements.
549 *       (for example via virtual mapping capabilities)
550 *       The routine returns the number of addr/length pairs actually
551 *       used, at most nents.
552 *
553 * Device ownership issues as mentioned above for pci_map_single are
554 * the same here.
555 */
556static int pci32_map_sg(struct device *device, struct scatterlist *sgl,
557			int nents, enum dma_data_direction dir,
558			unsigned long attrs)
559{
560	struct scatterlist *sg;
561	int n;
562
563	/* IIep is write-through, not flushing. */
564	for_each_sg(sgl, sg, nents, n) {
565		sg->dma_address = sg_phys(sg);
566		sg->dma_length = sg->length;
567	}
568	return nents;
569}
570
571/* Unmap a set of streaming mode DMA translations.
572 * Again, cpu read rules concerning calls here are the same as for
573 * pci_unmap_single() above.
574 */
575static void pci32_unmap_sg(struct device *dev, struct scatterlist *sgl,
576			   int nents, enum dma_data_direction dir,
577			   unsigned long attrs)
578{
579	struct scatterlist *sg;
580	int n;
581
582	if (dir != PCI_DMA_TODEVICE && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) {
583		for_each_sg(sgl, sg, nents, n) {
584			dma_make_coherent(sg_phys(sg), PAGE_ALIGN(sg->length));
585		}
586	}
587}
588
589/* Make physical memory consistent for a single
590 * streaming mode DMA translation before or after a transfer.
591 *
592 * If you perform a pci_map_single() but wish to interrogate the
593 * buffer using the cpu, yet do not wish to teardown the PCI dma
594 * mapping, you must call this function before doing so.  At the
595 * next point you give the PCI dma address back to the card, you
596 * must first perform a pci_dma_sync_for_device, and then the
597 * device again owns the buffer.
598 */
599static void pci32_sync_single_for_cpu(struct device *dev, dma_addr_t ba,
600				      size_t size, enum dma_data_direction dir)
601{
602	if (dir != PCI_DMA_TODEVICE) {
603		dma_make_coherent(ba, PAGE_ALIGN(size));
604	}
605}
606
607static void pci32_sync_single_for_device(struct device *dev, dma_addr_t ba,
608					 size_t size, enum dma_data_direction dir)
609{
610	if (dir != PCI_DMA_TODEVICE) {
611		dma_make_coherent(ba, PAGE_ALIGN(size));
612	}
613}
614
615/* Make physical memory consistent for a set of streaming
616 * mode DMA translations after a transfer.
617 *
618 * The same as pci_dma_sync_single_* but for a scatter-gather list,
619 * same rules and usage.
620 */
621static void pci32_sync_sg_for_cpu(struct device *dev, struct scatterlist *sgl,
622				  int nents, enum dma_data_direction dir)
623{
624	struct scatterlist *sg;
625	int n;
626
627	if (dir != PCI_DMA_TODEVICE) {
628		for_each_sg(sgl, sg, nents, n) {
629			dma_make_coherent(sg_phys(sg), PAGE_ALIGN(sg->length));
630		}
631	}
632}
633
634static void pci32_sync_sg_for_device(struct device *device, struct scatterlist *sgl,
635				     int nents, enum dma_data_direction dir)
636{
637	struct scatterlist *sg;
638	int n;
639
640	if (dir != PCI_DMA_TODEVICE) {
641		for_each_sg(sgl, sg, nents, n) {
642			dma_make_coherent(sg_phys(sg), PAGE_ALIGN(sg->length));
643		}
644	}
645}
646
647/* note: leon re-uses pci32_dma_ops */
648const struct dma_map_ops pci32_dma_ops = {
649	.alloc			= pci32_alloc_coherent,
650	.free			= pci32_free_coherent,
651	.map_page		= pci32_map_page,
652	.unmap_page		= pci32_unmap_page,
653	.map_sg			= pci32_map_sg,
654	.unmap_sg		= pci32_unmap_sg,
655	.sync_single_for_cpu	= pci32_sync_single_for_cpu,
656	.sync_single_for_device	= pci32_sync_single_for_device,
657	.sync_sg_for_cpu	= pci32_sync_sg_for_cpu,
658	.sync_sg_for_device	= pci32_sync_sg_for_device,
659};
660EXPORT_SYMBOL(pci32_dma_ops);
661
662const struct dma_map_ops *dma_ops = &sbus_dma_ops;
663EXPORT_SYMBOL(dma_ops);
664
665#ifdef CONFIG_PROC_FS
666
667static int sparc_io_proc_show(struct seq_file *m, void *v)
668{
669	struct resource *root = m->private, *r;
670	const char *nm;
671
672	for (r = root->child; r != NULL; r = r->sibling) {
673		if ((nm = r->name) == NULL) nm = "???";
674		seq_printf(m, "%016llx-%016llx: %s\n",
675				(unsigned long long)r->start,
676				(unsigned long long)r->end, nm);
677	}
678
679	return 0;
680}
681
682static int sparc_io_proc_open(struct inode *inode, struct file *file)
683{
684	return single_open(file, sparc_io_proc_show, PDE_DATA(inode));
685}
686
687static const struct file_operations sparc_io_proc_fops = {
688	.owner		= THIS_MODULE,
689	.open		= sparc_io_proc_open,
690	.read		= seq_read,
691	.llseek		= seq_lseek,
692	.release	= single_release,
693};
694#endif /* CONFIG_PROC_FS */
695
696static void register_proc_sparc_ioport(void)
697{
698#ifdef CONFIG_PROC_FS
699	proc_create_data("io_map", 0, NULL, &sparc_io_proc_fops, &sparc_iomap);
700	proc_create_data("dvma_map", 0, NULL, &sparc_io_proc_fops, &_sparc_dvma);
 
 
701#endif
702}
v6.2
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * ioport.c:  Simple io mapping allocator.
  4 *
  5 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
  6 * Copyright (C) 1995 Miguel de Icaza (miguel@nuclecu.unam.mx)
  7 *
  8 * 1996: sparc_free_io, 1999: ioremap()/iounmap() by Pete Zaitcev.
  9 *
 10 * 2000/01/29
 11 * <rth> zait: as long as pci_alloc_consistent produces something addressable, 
 12 *	things are ok.
 13 * <zaitcev> rth: no, it is relevant, because get_free_pages returns you a
 14 *	pointer into the big page mapping
 15 * <rth> zait: so what?
 16 * <rth> zait: remap_it_my_way(virt_to_phys(get_free_page()))
 17 * <zaitcev> Hmm
 18 * <zaitcev> Suppose I did this remap_it_my_way(virt_to_phys(get_free_page())).
 19 *	So far so good.
 20 * <zaitcev> Now, driver calls pci_free_consistent(with result of
 21 *	remap_it_my_way()).
 22 * <zaitcev> How do you find the address to pass to free_pages()?
 23 * <rth> zait: walk the page tables?  It's only two or three level after all.
 24 * <rth> zait: you have to walk them anyway to remove the mapping.
 25 * <zaitcev> Hmm
 26 * <zaitcev> Sounds reasonable
 27 */
 28
 29#include <linux/module.h>
 30#include <linux/sched.h>
 31#include <linux/kernel.h>
 32#include <linux/errno.h>
 33#include <linux/types.h>
 34#include <linux/ioport.h>
 35#include <linux/mm.h>
 36#include <linux/slab.h>
 37#include <linux/pci.h>		/* struct pci_dev */
 38#include <linux/proc_fs.h>
 39#include <linux/seq_file.h>
 40#include <linux/scatterlist.h>
 41#include <linux/dma-map-ops.h>
 42#include <linux/of_device.h>
 43
 44#include <asm/io.h>
 45#include <asm/vaddrs.h>
 46#include <asm/oplib.h>
 47#include <asm/prom.h>
 48#include <asm/page.h>
 49#include <asm/pgalloc.h>
 50#include <asm/dma.h>
 51#include <asm/iommu.h>
 52#include <asm/io-unit.h>
 53#include <asm/leon.h>
 54
 
 
 
 
 
 
 
 
 
 
 
 
 
 55static void __iomem *_sparc_ioremap(struct resource *res, u32 bus, u32 pa, int sz);
 56static void __iomem *_sparc_alloc_io(unsigned int busno, unsigned long phys,
 57    unsigned long size, char *name);
 58static void _sparc_free_io(struct resource *res);
 59
 60static void register_proc_sparc_ioport(void);
 61
 62/* This points to the next to use virtual memory for DVMA mappings */
 63static struct resource _sparc_dvma = {
 64	.name = "sparc_dvma", .start = DVMA_VADDR, .end = DVMA_END - 1
 65};
 66/* This points to the start of I/O mappings, cluable from outside. */
 67/*ext*/ struct resource sparc_iomap = {
 68	.name = "sparc_iomap", .start = IOBASE_VADDR, .end = IOBASE_END - 1
 69};
 70
 71/*
 72 * Our mini-allocator...
 73 * Boy this is gross! We need it because we must map I/O for
 74 * timers and interrupt controller before the kmalloc is available.
 75 */
 76
 77#define XNMLN  15
 78#define XNRES  10	/* SS-10 uses 8 */
 79
 80struct xresource {
 81	struct resource xres;	/* Must be first */
 82	int xflag;		/* 1 == used */
 83	char xname[XNMLN+1];
 84};
 85
 86static struct xresource xresv[XNRES];
 87
 88static struct xresource *xres_alloc(void) {
 89	struct xresource *xrp;
 90	int n;
 91
 92	xrp = xresv;
 93	for (n = 0; n < XNRES; n++) {
 94		if (xrp->xflag == 0) {
 95			xrp->xflag = 1;
 96			return xrp;
 97		}
 98		xrp++;
 99	}
100	return NULL;
101}
102
103static void xres_free(struct xresource *xrp) {
104	xrp->xflag = 0;
105}
106
107/*
108 * These are typically used in PCI drivers
109 * which are trying to be cross-platform.
110 *
111 * Bus type is always zero on IIep.
112 */
113void __iomem *ioremap(phys_addr_t offset, size_t size)
114{
115	char name[14];
116
117	sprintf(name, "phys_%08x", (u32)offset);
118	return _sparc_alloc_io(0, (unsigned long)offset, size, name);
119}
120EXPORT_SYMBOL(ioremap);
121
122/*
123 * Complementary to ioremap().
124 */
125void iounmap(volatile void __iomem *virtual)
126{
127	unsigned long vaddr = (unsigned long) virtual & PAGE_MASK;
128	struct resource *res;
129
130	/*
131	 * XXX Too slow. Can have 8192 DVMA pages on sun4m in the worst case.
132	 * This probably warrants some sort of hashing.
133	*/
134	if ((res = lookup_resource(&sparc_iomap, vaddr)) == NULL) {
135		printk("free_io/iounmap: cannot free %lx\n", vaddr);
136		return;
137	}
138	_sparc_free_io(res);
139
140	if ((char *)res >= (char*)xresv && (char *)res < (char *)&xresv[XNRES]) {
141		xres_free((struct xresource *)res);
142	} else {
143		kfree(res);
144	}
145}
146EXPORT_SYMBOL(iounmap);
147
148void __iomem *of_ioremap(struct resource *res, unsigned long offset,
149			 unsigned long size, char *name)
150{
151	return _sparc_alloc_io(res->flags & 0xF,
152			       res->start + offset,
153			       size, name);
154}
155EXPORT_SYMBOL(of_ioremap);
156
157void of_iounmap(struct resource *res, void __iomem *base, unsigned long size)
158{
159	iounmap(base);
160}
161EXPORT_SYMBOL(of_iounmap);
162
163/*
164 * Meat of mapping
165 */
166static void __iomem *_sparc_alloc_io(unsigned int busno, unsigned long phys,
167    unsigned long size, char *name)
168{
169	static int printed_full;
170	struct xresource *xres;
171	struct resource *res;
172	char *tack;
173	int tlen;
174	void __iomem *va;	/* P3 diag */
175
176	if (name == NULL) name = "???";
177
178	if ((xres = xres_alloc()) != NULL) {
179		tack = xres->xname;
180		res = &xres->xres;
181	} else {
182		if (!printed_full) {
183			printk("ioremap: done with statics, switching to malloc\n");
184			printed_full = 1;
185		}
186		tlen = strlen(name);
187		tack = kmalloc(sizeof (struct resource) + tlen + 1, GFP_KERNEL);
188		if (tack == NULL) return NULL;
189		memset(tack, 0, sizeof(struct resource));
190		res = (struct resource *) tack;
191		tack += sizeof (struct resource);
192	}
193
194	strlcpy(tack, name, XNMLN+1);
195	res->name = tack;
196
197	va = _sparc_ioremap(res, busno, phys, size);
198	/* printk("ioremap(0x%x:%08lx[0x%lx])=%p\n", busno, phys, size, va); */ /* P3 diag */
199	return va;
200}
201
202/*
203 */
204static void __iomem *
205_sparc_ioremap(struct resource *res, u32 bus, u32 pa, int sz)
206{
207	unsigned long offset = ((unsigned long) pa) & (~PAGE_MASK);
208
209	if (allocate_resource(&sparc_iomap, res,
210	    (offset + sz + PAGE_SIZE-1) & PAGE_MASK,
211	    sparc_iomap.start, sparc_iomap.end, PAGE_SIZE, NULL, NULL) != 0) {
212		/* Usually we cannot see printks in this case. */
213		prom_printf("alloc_io_res(%s): cannot occupy\n",
214		    (res->name != NULL)? res->name: "???");
215		prom_halt();
216	}
217
218	pa &= PAGE_MASK;
219	srmmu_mapiorange(bus, pa, res->start, resource_size(res));
220
221	return (void __iomem *)(unsigned long)(res->start + offset);
222}
223
224/*
225 * Complementary to _sparc_ioremap().
226 */
227static void _sparc_free_io(struct resource *res)
228{
229	unsigned long plen;
230
231	plen = resource_size(res);
232	BUG_ON((plen & (PAGE_SIZE-1)) != 0);
233	srmmu_unmapiorange(res->start, plen);
234	release_resource(res);
235}
236
237unsigned long sparc_dma_alloc_resource(struct device *dev, size_t len)
 
 
238{
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
239	struct resource *res;
 
240
241	res = kzalloc(sizeof(*res), GFP_KERNEL);
242	if (!res)
243		return 0;
244	res->name = dev->of_node->full_name;
 
 
 
 
245
246	if (allocate_resource(&_sparc_dvma, res, len, _sparc_dvma.start,
247			      _sparc_dvma.end, PAGE_SIZE, NULL, NULL) != 0) {
248		printk("%s: cannot occupy 0x%zx", __func__, len);
249		kfree(res);
250		return 0;
 
 
 
 
 
 
 
251	}
252
253	return res->start;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
254}
255
256bool sparc_dma_free_resource(void *cpu_addr, size_t size)
 
257{
258	unsigned long addr = (unsigned long)cpu_addr;
259	struct resource *res;
 
 
 
 
 
 
 
260
261	res = lookup_resource(&_sparc_dvma, addr);
262	if (!res) {
263		printk("%s: cannot free %p\n", __func__, cpu_addr);
264		return false;
265	}
266
267	if ((addr & (PAGE_SIZE - 1)) != 0) {
268		printk("%s: unaligned va %p\n", __func__, cpu_addr);
269		return false;
270	}
271
272	size = PAGE_ALIGN(size);
273	if (resource_size(res) != size) {
274		printk("%s: region 0x%lx asked 0x%zx\n",
275			__func__, (long)resource_size(res), size);
276		return false;
277	}
278
279	release_resource(res);
280	kfree(res);
281	return true;
 
 
 
 
282}
283
284#ifdef CONFIG_SBUS
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
285
286void sbus_set_sbus64(struct device *dev, int x)
287{
288	printk("sbus_set_sbus64: unsupported\n");
289}
290EXPORT_SYMBOL(sbus_set_sbus64);
 
 
 
 
 
 
 
 
 
 
 
291
292static int __init sparc_register_ioport(void)
293{
294	register_proc_sparc_ioport();
295
296	return 0;
297}
298
299arch_initcall(sparc_register_ioport);
300
301#endif /* CONFIG_SBUS */
302
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
303/*
304 * IIep is write-through, not flushing on cpu to device transfer.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
305 *
306 * On LEON systems without cache snooping, the entire D-CACHE must be flushed to
307 * make DMA to cacheable memory coherent.
 
 
 
 
 
 
308 */
309void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
310		enum dma_data_direction dir)
 
311{
312	if (dir != DMA_TO_DEVICE &&
313	    sparc_cpu_model == sparc_leon &&
314	    !sparc_leon3_snooping_enabled())
315		leon_flush_dcache_all();
 
 
 
 
 
316}
317
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
318#ifdef CONFIG_PROC_FS
319
320static int sparc_io_proc_show(struct seq_file *m, void *v)
321{
322	struct resource *root = m->private, *r;
323	const char *nm;
324
325	for (r = root->child; r != NULL; r = r->sibling) {
326		if ((nm = r->name) == NULL) nm = "???";
327		seq_printf(m, "%016llx-%016llx: %s\n",
328				(unsigned long long)r->start,
329				(unsigned long long)r->end, nm);
330	}
331
332	return 0;
333}
 
 
 
 
 
 
 
 
 
 
 
 
 
334#endif /* CONFIG_PROC_FS */
335
336static void register_proc_sparc_ioport(void)
337{
338#ifdef CONFIG_PROC_FS
339	proc_create_single_data("io_map", 0, NULL, sparc_io_proc_show,
340			&sparc_iomap);
341	proc_create_single_data("dvma_map", 0, NULL, sparc_io_proc_show,
342			&_sparc_dvma);
343#endif
344}