/arch/sh/drivers/pci/pci.c

  1/*
  2 * New-style PCI core.
  3 *
  4 * Copyright (c) 2004 - 2009  Paul Mundt
  5 * Copyright (c) 2002  M. R. Brown
  6 *
  7 * Modelled after arch/mips/pci/pci.c:
  8 *  Copyright (C) 2003, 04 Ralf Baechle (ralf@linux-mips.org)
  9 *
 10 * This file is subject to the terms and conditions of the GNU General Public
 11 * License.  See the file "COPYING" in the main directory of this archive
 12 * for more details.
 13 */
 14#include <linux/kernel.h>
 15#include <linux/mm.h>
 16#include <linux/pci.h>
 17#include <linux/init.h>
 18#include <linux/types.h>
 19#include <linux/dma-debug.h>
 20#include <linux/io.h>
 21#include <linux/mutex.h>
 22
 23unsigned long PCIBIOS_MIN_IO = 0x0000;
 24unsigned long PCIBIOS_MIN_MEM = 0;
 25
 26/*
 27 * The PCI controller list.
 28 */
 29static struct pci_channel *hose_head, **hose_tail = &hose_head;
 30
 31static int pci_initialized;
 32
 33static void __devinit pcibios_scanbus(struct pci_channel *hose)
 34{
 35	static int next_busno;
 36	static int need_domain_info;
 37	struct pci_bus *bus;
 38
 39	bus = pci_scan_bus(next_busno, hose->pci_ops, hose);
 40	hose->bus = bus;
 41
 42	need_domain_info = need_domain_info || hose->index;
 43	hose->need_domain_info = need_domain_info;
 44	if (bus) {
 45		next_busno = bus->subordinate + 1;
 46		/* Don't allow 8-bit bus number overflow inside the hose -
 47		   reserve some space for bridges. */
 48		if (next_busno > 224) {
 49			next_busno = 0;
 50			need_domain_info = 1;
 51		}
 52
 53		pci_bus_size_bridges(bus);
 54		pci_bus_assign_resources(bus);
 55		pci_enable_bridges(bus);
 56	}
 57}
 58
 59static DEFINE_MUTEX(pci_scan_mutex);
 60
 61int __devinit register_pci_controller(struct pci_channel *hose)
 62{
 63	int i;
 64
 65	for (i = 0; i < hose->nr_resources; i++) {
 66		struct resource *res = hose->resources + i;
 67
 68		if (res->flags & IORESOURCE_IO) {
 69			if (request_resource(&ioport_resource, res) < 0)
 70				goto out;
 71		} else {
 72			if (request_resource(&iomem_resource, res) < 0)
 73				goto out;
 74		}
 75	}
 76
 77	*hose_tail = hose;
 78	hose_tail = &hose->next;
 79
 80	/*
 81	 * Do not panic here but later - this might hapen before console init.
 82	 */
 83	if (!hose->io_map_base) {
 84		printk(KERN_WARNING
 85		       "registering PCI controller with io_map_base unset\n");
 86	}
 87
 88	/*
 89	 * Setup the ERR/PERR and SERR timers, if available.
 90	 */
 91	pcibios_enable_timers(hose);
 92
 93	/*
 94	 * Scan the bus if it is register after the PCI subsystem
 95	 * initialization.
 96	 */
 97	if (pci_initialized) {
 98		mutex_lock(&pci_scan_mutex);
 99		pcibios_scanbus(hose);
100		mutex_unlock(&pci_scan_mutex);
101	}
102
103	return 0;
104
105out:
106	for (--i; i >= 0; i--)
107		release_resource(&hose->resources[i]);
108
109	printk(KERN_WARNING "Skipping PCI bus scan due to resource conflict\n");
110	return -1;
111}
112
113static int __init pcibios_init(void)
114{
115	struct pci_channel *hose;
116
117	/* Scan all of the recorded PCI controllers.  */
118	for (hose = hose_head; hose; hose = hose->next)
119		pcibios_scanbus(hose);
120
121	pci_fixup_irqs(pci_common_swizzle, pcibios_map_platform_irq);
122
123	dma_debug_add_bus(&pci_bus_type);
124
125	pci_initialized = 1;
126
127	return 0;
128}
129subsys_initcall(pcibios_init);
130
131static void pcibios_fixup_device_resources(struct pci_dev *dev,
132	struct pci_bus *bus)
133{
134	/* Update device resources.  */
135	struct pci_channel *hose = bus->sysdata;
136	unsigned long offset = 0;
137	int i;
138
139	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
140		if (!dev->resource[i].start)
141			continue;
142		if (dev->resource[i].flags & IORESOURCE_IO)
143			offset = hose->io_offset;
144		else if (dev->resource[i].flags & IORESOURCE_MEM)
145			offset = hose->mem_offset;
146
147		dev->resource[i].start += offset;
148		dev->resource[i].end += offset;
149	}
150}
151
152/*
153 *  Called after each bus is probed, but before its children
154 *  are examined.
155 */
156void __devinit pcibios_fixup_bus(struct pci_bus *bus)
157{
158	struct pci_dev *dev = bus->self;
159	struct list_head *ln;
160	struct pci_channel *hose = bus->sysdata;
161
162	if (!dev) {
163		int i;
164
165		for (i = 0; i < hose->nr_resources; i++)
166			bus->resource[i] = hose->resources + i;
167	}
168
169	for (ln = bus->devices.next; ln != &bus->devices; ln = ln->next) {
170		dev = pci_dev_b(ln);
171
172		if ((dev->class >> 8) != PCI_CLASS_BRIDGE_PCI)
173			pcibios_fixup_device_resources(dev, bus);
174	}
175}
176
177/*
178 * We need to avoid collisions with `mirrored' VGA ports
179 * and other strange ISA hardware, so we always want the
180 * addresses to be allocated in the 0x000-0x0ff region
181 * modulo 0x400.
182 */
183resource_size_t pcibios_align_resource(void *data, const struct resource *res,
184				resource_size_t size, resource_size_t align)
185{
186	struct pci_dev *dev = data;
187	struct pci_channel *hose = dev->sysdata;
188	resource_size_t start = res->start;
189
190	if (res->flags & IORESOURCE_IO) {
191		if (start < PCIBIOS_MIN_IO + hose->resources[0].start)
192			start = PCIBIOS_MIN_IO + hose->resources[0].start;
193
194		/*
195                 * Put everything into 0x00-0xff region modulo 0x400.
196		 */
197		if (start & 0x300)
198			start = (start + 0x3ff) & ~0x3ff;
199	}
200
201	return start;
202}
203
204void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
205			     struct resource *res)
206{
207	struct pci_channel *hose = dev->sysdata;
208	unsigned long offset = 0;
209
210	if (res->flags & IORESOURCE_IO)
211		offset = hose->io_offset;
212	else if (res->flags & IORESOURCE_MEM)
213		offset = hose->mem_offset;
214
215	region->start = res->start - offset;
216	region->end = res->end - offset;
217}
218
219void pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
220			     struct pci_bus_region *region)
221{
222	struct pci_channel *hose = dev->sysdata;
223	unsigned long offset = 0;
224
225	if (res->flags & IORESOURCE_IO)
226		offset = hose->io_offset;
227	else if (res->flags & IORESOURCE_MEM)
228		offset = hose->mem_offset;
229
230	res->start = region->start + offset;
231	res->end = region->end + offset;
232}
233
234int pcibios_enable_device(struct pci_dev *dev, int mask)
235{
236	u16 cmd, old_cmd;
237	int idx;
238	struct resource *r;
239
240	pci_read_config_word(dev, PCI_COMMAND, &cmd);
241	old_cmd = cmd;
242	for (idx=0; idx < PCI_NUM_RESOURCES; idx++) {
243		/* Only set up the requested stuff */
244		if (!(mask & (1<<idx)))
245			continue;
246
247		r = &dev->resource[idx];
248		if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
249			continue;
250		if ((idx == PCI_ROM_RESOURCE) &&
251				(!(r->flags & IORESOURCE_ROM_ENABLE)))
252			continue;
253		if (!r->start && r->end) {
254			printk(KERN_ERR "PCI: Device %s not available "
255			       "because of resource collisions\n",
256			       pci_name(dev));
257			return -EINVAL;
258		}
259		if (r->flags & IORESOURCE_IO)
260			cmd |= PCI_COMMAND_IO;
261		if (r->flags & IORESOURCE_MEM)
262			cmd |= PCI_COMMAND_MEMORY;
263	}
264	if (cmd != old_cmd) {
265		printk("PCI: Enabling device %s (%04x -> %04x)\n",
266		       pci_name(dev), old_cmd, cmd);
267		pci_write_config_word(dev, PCI_COMMAND, cmd);
268	}
269	return 0;
270}
271
272/*
273 *  If we set up a device for bus mastering, we need to check and set
274 *  the latency timer as it may not be properly set.
275 */
276static unsigned int pcibios_max_latency = 255;
277
278void pcibios_set_master(struct pci_dev *dev)
279{
280	u8 lat;
281	pci_read_config_byte(dev, PCI_LATENCY_TIMER, &lat);
282	if (lat < 16)
283		lat = (64 <= pcibios_max_latency) ? 64 : pcibios_max_latency;
284	else if (lat > pcibios_max_latency)
285		lat = pcibios_max_latency;
286	else
287		return;
288	printk(KERN_INFO "PCI: Setting latency timer of device %s to %d\n",
289	       pci_name(dev), lat);
290	pci_write_config_byte(dev, PCI_LATENCY_TIMER, lat);
291}
292
293void __init pcibios_update_irq(struct pci_dev *dev, int irq)
294{
295	pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
296}
297
298char * __devinit pcibios_setup(char *str)
299{
300	return str;
301}
302
303static void __init
304pcibios_bus_report_status_early(struct pci_channel *hose,
305				int top_bus, int current_bus,
306				unsigned int status_mask, int warn)
307{
308	unsigned int pci_devfn;
309	u16 status;
310	int ret;
311
312	for (pci_devfn = 0; pci_devfn < 0xff; pci_devfn++) {
313		if (PCI_FUNC(pci_devfn))
314			continue;
315		ret = early_read_config_word(hose, top_bus, current_bus,
316					     pci_devfn, PCI_STATUS, &status);
317		if (ret != PCIBIOS_SUCCESSFUL)
318			continue;
319		if (status == 0xffff)
320			continue;
321
322		early_write_config_word(hose, top_bus, current_bus,
323					pci_devfn, PCI_STATUS,
324					status & status_mask);
325		if (warn)
326			printk("(%02x:%02x: %04X) ", current_bus,
327			       pci_devfn, status);
328	}
329}
330
331/*
332 * We can't use pci_find_device() here since we are
333 * called from interrupt context.
334 */
335static void __init_refok
336pcibios_bus_report_status(struct pci_bus *bus, unsigned int status_mask,
337			  int warn)
338{
339	struct pci_dev *dev;
340
341	list_for_each_entry(dev, &bus->devices, bus_list) {
342		u16 status;
343
344		/*
345		 * ignore host bridge - we handle
346		 * that separately
347		 */
348		if (dev->bus->number == 0 && dev->devfn == 0)
349			continue;
350
351		pci_read_config_word(dev, PCI_STATUS, &status);
352		if (status == 0xffff)
353			continue;
354
355		if ((status & status_mask) == 0)
356			continue;
357
358		/* clear the status errors */
359		pci_write_config_word(dev, PCI_STATUS, status & status_mask);
360
361		if (warn)
362			printk("(%s: %04X) ", pci_name(dev), status);
363	}
364
365	list_for_each_entry(dev, &bus->devices, bus_list)
366		if (dev->subordinate)
367			pcibios_bus_report_status(dev->subordinate, status_mask, warn);
368}
369
370void __init_refok pcibios_report_status(unsigned int status_mask, int warn)
371{
372	struct pci_channel *hose;
373
374	for (hose = hose_head; hose; hose = hose->next) {
375		if (unlikely(!hose->bus))
376			pcibios_bus_report_status_early(hose, hose_head->index,
377					hose->index, status_mask, warn);
378		else
379			pcibios_bus_report_status(hose->bus, status_mask, warn);
380	}
381}
382
383int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
384			enum pci_mmap_state mmap_state, int write_combine)
385{
386	/*
387	 * I/O space can be accessed via normal processor loads and stores on
388	 * this platform but for now we elect not to do this and portable
389	 * drivers should not do this anyway.
390	 */
391	if (mmap_state == pci_mmap_io)
392		return -EINVAL;
393
394	/*
395	 * Ignore write-combine; for now only return uncached mappings.
396	 */
397	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
398
399	return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
400			       vma->vm_end - vma->vm_start,
401			       vma->vm_page_prot);
402}
403
404#ifndef CONFIG_GENERIC_IOMAP
405
406static void __iomem *ioport_map_pci(struct pci_dev *dev,
407				    unsigned long port, unsigned int nr)
408{
409	struct pci_channel *chan = dev->sysdata;
410
411	if (unlikely(!chan->io_map_base)) {
412		chan->io_map_base = generic_io_base;
413
414		if (pci_domains_supported)
415			panic("To avoid data corruption io_map_base MUST be "
416			      "set with multiple PCI domains.");
417	}
418
419
420	return (void __iomem *)(chan->io_map_base + port);
421}
422
423void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen)
424{
425	resource_size_t start = pci_resource_start(dev, bar);
426	resource_size_t len = pci_resource_len(dev, bar);
427	unsigned long flags = pci_resource_flags(dev, bar);
428
429	if (unlikely(!len || !start))
430		return NULL;
431	if (maxlen && len > maxlen)
432		len = maxlen;
433
434	if (flags & IORESOURCE_IO)
435		return ioport_map_pci(dev, start, len);
436	if (flags & IORESOURCE_MEM) {
437		if (flags & IORESOURCE_CACHEABLE)
438			return ioremap(start, len);
439		return ioremap_nocache(start, len);
440	}
441
442	return NULL;
443}
444EXPORT_SYMBOL(pci_iomap);
445
446void pci_iounmap(struct pci_dev *dev, void __iomem *addr)
447{
448	iounmap(addr);
449}
450EXPORT_SYMBOL(pci_iounmap);
451
452#endif /* CONFIG_GENERIC_IOMAP */
453
454#ifdef CONFIG_HOTPLUG
455EXPORT_SYMBOL(pcibios_resource_to_bus);
456EXPORT_SYMBOL(pcibios_bus_to_resource);
457EXPORT_SYMBOL(PCIBIOS_MIN_IO);
458EXPORT_SYMBOL(PCIBIOS_MIN_MEM);
459#endif