1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *	linux/arch/alpha/kernel/pci.c
4  *
5  * Extruded from code written by
6  *	Dave Rusling (david.rusling@reo.mts.dec.com)
7  *	David Mosberger (davidm@cs.arizona.edu)
8  */
9 
10 /* 2.3.x PCI/resources, 1999 Andrea Arcangeli <andrea@suse.de> */
11 
12 /*
13  * Nov 2000, Ivan Kokshaysky <ink@jurassic.park.msu.ru>
14  *	     PCI-PCI bridges cleanup
15  */
16 #include <linux/string.h>
17 #include <linux/pci.h>
18 #include <linux/init.h>
19 #include <linux/ioport.h>
20 #include <linux/kernel.h>
21 #include <linux/memblock.h>
22 #include <linux/module.h>
23 #include <linux/cache.h>
24 #include <linux/slab.h>
25 #include <linux/syscalls.h>
26 #include <asm/machvec.h>
27 
28 #include "proto.h"
29 #include "pci_impl.h"
30 
31 
32 /*
33  * Some string constants used by the various core logics.
34  */
35 
36 const char *const pci_io_names[] = {
37   "PCI IO bus 0", "PCI IO bus 1", "PCI IO bus 2", "PCI IO bus 3",
38   "PCI IO bus 4", "PCI IO bus 5", "PCI IO bus 6", "PCI IO bus 7"
39 };
40 
41 const char *const pci_mem_names[] = {
42   "PCI mem bus 0", "PCI mem bus 1", "PCI mem bus 2", "PCI mem bus 3",
43   "PCI mem bus 4", "PCI mem bus 5", "PCI mem bus 6", "PCI mem bus 7"
44 };
45 
46 const char pci_hae0_name[] = "HAE0";
47 
48 /*
49  * If PCI_PROBE_ONLY in pci_flags is set, we don't change any PCI resource
50  * assignments.
51  */
52 
53 /*
54  * The PCI controller list.
55  */
56 
57 struct pci_controller *hose_head, **hose_tail = &hose_head;
58 struct pci_controller *pci_isa_hose;
59 
60 /*
61  * Quirks.
62  */
63 
quirk_isa_bridge(struct pci_dev * dev)64 static void quirk_isa_bridge(struct pci_dev *dev)
65 {
66 	dev->class = PCI_CLASS_BRIDGE_ISA << 8;
67 }
68 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82378, quirk_isa_bridge);
69 
quirk_cypress(struct pci_dev * dev)70 static void quirk_cypress(struct pci_dev *dev)
71 {
72 	/* The Notorious Cy82C693 chip.  */
73 
74 	/* The generic legacy mode IDE fixup in drivers/pci/probe.c
75 	   doesn't work correctly with the Cypress IDE controller as
76 	   it has non-standard register layout.  Fix that.  */
77 	if (dev->class >> 8 == PCI_CLASS_STORAGE_IDE) {
78 		dev->resource[2].start = dev->resource[3].start = 0;
79 		dev->resource[2].end = dev->resource[3].end = 0;
80 		dev->resource[2].flags = dev->resource[3].flags = 0;
81 		if (PCI_FUNC(dev->devfn) == 2) {
82 			dev->resource[0].start = 0x170;
83 			dev->resource[0].end = 0x177;
84 			dev->resource[1].start = 0x376;
85 			dev->resource[1].end = 0x376;
86 		}
87 	}
88 
89 	/* The Cypress bridge responds on the PCI bus in the address range
90 	   0xffff0000-0xffffffff (conventional x86 BIOS ROM).  There is no
91 	   way to turn this off.  The bridge also supports several extended
92 	   BIOS ranges (disabled after power-up), and some consoles do turn
93 	   them on.  So if we use a large direct-map window, or a large SG
94 	   window, we must avoid the entire 0xfff00000-0xffffffff region.  */
95 	if (dev->class >> 8 == PCI_CLASS_BRIDGE_ISA) {
96 		if (__direct_map_base + __direct_map_size >= 0xfff00000UL)
97 			__direct_map_size = 0xfff00000UL - __direct_map_base;
98 		else {
99 			struct pci_controller *hose = dev->sysdata;
100 			struct pci_iommu_arena *pci = hose->sg_pci;
101 			if (pci && pci->dma_base + pci->size >= 0xfff00000UL)
102 				pci->size = 0xfff00000UL - pci->dma_base;
103 		}
104 	}
105 }
106 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_CONTAQ, PCI_DEVICE_ID_CONTAQ_82C693, quirk_cypress);
107 
108 /* Called for each device after PCI setup is done. */
pcibios_fixup_final(struct pci_dev * dev)109 static void pcibios_fixup_final(struct pci_dev *dev)
110 {
111 	unsigned int class = dev->class >> 8;
112 
113 	if (class == PCI_CLASS_BRIDGE_ISA || class == PCI_CLASS_BRIDGE_EISA) {
114 		dev->dma_mask = MAX_ISA_DMA_ADDRESS - 1;
115 		isa_bridge = dev;
116 	}
117 }
118 DECLARE_PCI_FIXUP_FINAL(PCI_ANY_ID, PCI_ANY_ID, pcibios_fixup_final);
119 
120 /* Just declaring that the power-of-ten prefixes are actually the
121    power-of-two ones doesn't make it true :) */
122 #define KB			1024
123 #define MB			(1024*KB)
124 #define GB			(1024*MB)
125 
126 resource_size_t
pcibios_align_resource(void * data,const struct resource * res,resource_size_t size,resource_size_t align)127 pcibios_align_resource(void *data, const struct resource *res,
128 		       resource_size_t size, resource_size_t align)
129 {
130 	struct pci_dev *dev = data;
131 	struct pci_controller *hose = dev->sysdata;
132 	unsigned long alignto;
133 	resource_size_t start = res->start;
134 
135 	if (res->flags & IORESOURCE_IO) {
136 		/* Make sure we start at our min on all hoses */
137 		if (start - hose->io_space->start < PCIBIOS_MIN_IO)
138 			start = PCIBIOS_MIN_IO + hose->io_space->start;
139 
140 		/*
141 		 * Put everything into 0x00-0xff region modulo 0x400
142 		 */
143 		if (start & 0x300)
144 			start = (start + 0x3ff) & ~0x3ff;
145 	}
146 	else if	(res->flags & IORESOURCE_MEM) {
147 		/* Make sure we start at our min on all hoses */
148 		if (start - hose->mem_space->start < PCIBIOS_MIN_MEM)
149 			start = PCIBIOS_MIN_MEM + hose->mem_space->start;
150 
151 		/*
152 		 * The following holds at least for the Low Cost
153 		 * Alpha implementation of the PCI interface:
154 		 *
155 		 * In sparse memory address space, the first
156 		 * octant (16MB) of every 128MB segment is
157 		 * aliased to the very first 16 MB of the
158 		 * address space (i.e., it aliases the ISA
159 		 * memory address space).  Thus, we try to
160 		 * avoid allocating PCI devices in that range.
161 		 * Can be allocated in 2nd-7th octant only.
162 		 * Devices that need more than 112MB of
163 		 * address space must be accessed through
164 		 * dense memory space only!
165 		 */
166 
167 		/* Align to multiple of size of minimum base.  */
168 		alignto = max_t(resource_size_t, 0x1000, align);
169 		start = ALIGN(start, alignto);
170 		if (hose->sparse_mem_base && size <= 7 * 16*MB) {
171 			if (((start / (16*MB)) & 0x7) == 0) {
172 				start &= ~(128*MB - 1);
173 				start += 16*MB;
174 				start  = ALIGN(start, alignto);
175 			}
176 			if (start/(128*MB) != (start + size - 1)/(128*MB)) {
177 				start &= ~(128*MB - 1);
178 				start += (128 + 16)*MB;
179 				start  = ALIGN(start, alignto);
180 			}
181 		}
182 	}
183 
184 	return start;
185 }
186 #undef KB
187 #undef MB
188 #undef GB
189 
190 static int __init
pcibios_init(void)191 pcibios_init(void)
192 {
193 	if (alpha_mv.init_pci)
194 		alpha_mv.init_pci();
195 	return 0;
196 }
197 
198 subsys_initcall(pcibios_init);
199 
200 #ifdef ALPHA_RESTORE_SRM_SETUP
201 /* Store PCI device configuration left by SRM here. */
202 struct pdev_srm_saved_conf
203 {
204 	struct pdev_srm_saved_conf *next;
205 	struct pci_dev *dev;
206 };
207 
208 static struct pdev_srm_saved_conf *srm_saved_configs;
209 
pdev_save_srm_config(struct pci_dev * dev)210 static void pdev_save_srm_config(struct pci_dev *dev)
211 {
212 	struct pdev_srm_saved_conf *tmp;
213 	static int printed = 0;
214 
215 	if (!alpha_using_srm || pci_has_flag(PCI_PROBE_ONLY))
216 		return;
217 
218 	if (!printed) {
219 		printk(KERN_INFO "pci: enabling save/restore of SRM state\n");
220 		printed = 1;
221 	}
222 
223 	tmp = kmalloc(sizeof(*tmp), GFP_KERNEL);
224 	if (!tmp) {
225 		printk(KERN_ERR "%s: kmalloc() failed!\n", __func__);
226 		return;
227 	}
228 	tmp->next = srm_saved_configs;
229 	tmp->dev = dev;
230 
231 	pci_save_state(dev);
232 
233 	srm_saved_configs = tmp;
234 }
235 
236 void
pci_restore_srm_config(void)237 pci_restore_srm_config(void)
238 {
239 	struct pdev_srm_saved_conf *tmp;
240 
241 	/* No need to restore if probed only. */
242 	if (pci_has_flag(PCI_PROBE_ONLY))
243 		return;
244 
245 	/* Restore SRM config. */
246 	for (tmp = srm_saved_configs; tmp; tmp = tmp->next) {
247 		pci_restore_state(tmp->dev);
248 	}
249 }
250 #else
251 #define pdev_save_srm_config(dev)	do {} while (0)
252 #endif
253 
pcibios_fixup_bus(struct pci_bus * bus)254 void pcibios_fixup_bus(struct pci_bus *bus)
255 {
256 	struct pci_dev *dev = bus->self;
257 
258 	if (pci_has_flag(PCI_PROBE_ONLY) && dev &&
259 	    (dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
260 		pci_read_bridge_bases(bus);
261 	}
262 
263 	list_for_each_entry(dev, &bus->devices, bus_list) {
264 		pdev_save_srm_config(dev);
265 	}
266 }
267 
268 /*
269  *  If we set up a device for bus mastering, we need to check the latency
270  *  timer as certain firmware forgets to set it properly, as seen
271  *  on SX164 and LX164 with SRM.
272  */
273 void
pcibios_set_master(struct pci_dev * dev)274 pcibios_set_master(struct pci_dev *dev)
275 {
276 	u8 lat;
277 	pci_read_config_byte(dev, PCI_LATENCY_TIMER, &lat);
278 	if (lat >= 16) return;
279 	printk("PCI: Setting latency timer of device %s to 64\n",
280 							pci_name(dev));
281 	pci_write_config_byte(dev, PCI_LATENCY_TIMER, 64);
282 }
283 
284 void __init
pcibios_claim_one_bus(struct pci_bus * b)285 pcibios_claim_one_bus(struct pci_bus *b)
286 {
287 	struct pci_dev *dev;
288 	struct pci_bus *child_bus;
289 
290 	list_for_each_entry(dev, &b->devices, bus_list) {
291 		int i;
292 
293 		for (i = 0; i < PCI_NUM_RESOURCES; i++) {
294 			struct resource *r = &dev->resource[i];
295 
296 			if (r->parent || !r->start || !r->flags)
297 				continue;
298 			if (pci_has_flag(PCI_PROBE_ONLY) ||
299 			    (r->flags & IORESOURCE_PCI_FIXED)) {
300 				if (pci_claim_resource(dev, i) == 0)
301 					continue;
302 
303 				pci_claim_bridge_resource(dev, i);
304 			}
305 		}
306 	}
307 
308 	list_for_each_entry(child_bus, &b->children, node)
309 		pcibios_claim_one_bus(child_bus);
310 }
311 
312 static void __init
pcibios_claim_console_setup(void)313 pcibios_claim_console_setup(void)
314 {
315 	struct pci_bus *b;
316 
317 	list_for_each_entry(b, &pci_root_buses, node)
318 		pcibios_claim_one_bus(b);
319 }
320 
321 void __init
common_init_pci(void)322 common_init_pci(void)
323 {
324 	struct pci_controller *hose;
325 	struct list_head resources;
326 	struct pci_host_bridge *bridge;
327 	struct pci_bus *bus;
328 	int ret, next_busno;
329 	int need_domain_info = 0;
330 	u32 pci_mem_end;
331 	u32 sg_base;
332 	unsigned long end;
333 
334 	/* Scan all of the recorded PCI controllers.  */
335 	for (next_busno = 0, hose = hose_head; hose; hose = hose->next) {
336 		sg_base = hose->sg_pci ? hose->sg_pci->dma_base : ~0;
337 
338 		/* Adjust hose mem_space limit to prevent PCI allocations
339 		   in the iommu windows. */
340 		pci_mem_end = min((u32)__direct_map_base, sg_base) - 1;
341 		end = hose->mem_space->start + pci_mem_end;
342 		if (hose->mem_space->end > end)
343 			hose->mem_space->end = end;
344 
345 		INIT_LIST_HEAD(&resources);
346 		pci_add_resource_offset(&resources, hose->io_space,
347 					hose->io_space->start);
348 		pci_add_resource_offset(&resources, hose->mem_space,
349 					hose->mem_space->start);
350 
351 		bridge = pci_alloc_host_bridge(0);
352 		if (!bridge)
353 			continue;
354 
355 		list_splice_init(&resources, &bridge->windows);
356 		bridge->dev.parent = NULL;
357 		bridge->sysdata = hose;
358 		bridge->busnr = next_busno;
359 		bridge->ops = alpha_mv.pci_ops;
360 		bridge->swizzle_irq = alpha_mv.pci_swizzle;
361 		bridge->map_irq = alpha_mv.pci_map_irq;
362 
363 		ret = pci_scan_root_bus_bridge(bridge);
364 		if (ret) {
365 			pci_free_host_bridge(bridge);
366 			continue;
367 		}
368 
369 		bus = hose->bus = bridge->bus;
370 		hose->need_domain_info = need_domain_info;
371 		next_busno = bus->busn_res.end + 1;
372 		/* Don't allow 8-bit bus number overflow inside the hose -
373 		   reserve some space for bridges. */
374 		if (next_busno > 224) {
375 			next_busno = 0;
376 			need_domain_info = 1;
377 		}
378 	}
379 
380 	pcibios_claim_console_setup();
381 
382 	pci_assign_unassigned_resources();
383 	for (hose = hose_head; hose; hose = hose->next) {
384 		bus = hose->bus;
385 		if (bus)
386 			pci_bus_add_devices(bus);
387 	}
388 }
389 
390 struct pci_controller * __init
alloc_pci_controller(void)391 alloc_pci_controller(void)
392 {
393 	struct pci_controller *hose;
394 
395 	hose = memblock_alloc(sizeof(*hose), SMP_CACHE_BYTES);
396 	if (!hose)
397 		panic("%s: Failed to allocate %zu bytes\n", __func__,
398 		      sizeof(*hose));
399 
400 	*hose_tail = hose;
401 	hose_tail = &hose->next;
402 
403 	return hose;
404 }
405 
406 struct resource * __init
alloc_resource(void)407 alloc_resource(void)
408 {
409 	void *ptr = memblock_alloc(sizeof(struct resource), SMP_CACHE_BYTES);
410 
411 	if (!ptr)
412 		panic("%s: Failed to allocate %zu bytes\n", __func__,
413 		      sizeof(struct resource));
414 
415 	return ptr;
416 }
417 
418 
419 /* Provide information on locations of various I/O regions in physical
420    memory.  Do this on a per-card basis so that we choose the right hose.  */
421 
SYSCALL_DEFINE3(pciconfig_iobase,long,which,unsigned long,bus,unsigned long,dfn)422 SYSCALL_DEFINE3(pciconfig_iobase, long, which, unsigned long, bus,
423 		unsigned long, dfn)
424 {
425 	struct pci_controller *hose;
426 	struct pci_dev *dev;
427 
428 	/* from hose or from bus.devfn */
429 	if (which & IOBASE_FROM_HOSE) {
430 		for(hose = hose_head; hose; hose = hose->next)
431 			if (hose->index == bus) break;
432 		if (!hose) return -ENODEV;
433 	} else {
434 		/* Special hook for ISA access.  */
435 		if (bus == 0 && dfn == 0) {
436 			hose = pci_isa_hose;
437 		} else {
438 			dev = pci_get_domain_bus_and_slot(0, bus, dfn);
439 			if (!dev)
440 				return -ENODEV;
441 			hose = dev->sysdata;
442 			pci_dev_put(dev);
443 		}
444 	}
445 
446 	switch (which & ~IOBASE_FROM_HOSE) {
447 	case IOBASE_HOSE:
448 		return hose->index;
449 	case IOBASE_SPARSE_MEM:
450 		return hose->sparse_mem_base;
451 	case IOBASE_DENSE_MEM:
452 		return hose->dense_mem_base;
453 	case IOBASE_SPARSE_IO:
454 		return hose->sparse_io_base;
455 	case IOBASE_DENSE_IO:
456 		return hose->dense_io_base;
457 	case IOBASE_ROOT_BUS:
458 		return hose->bus->number;
459 	}
460 
461 	return -EOPNOTSUPP;
462 }
463 
464 /* Destroy an __iomem token.  Not copied from lib/iomap.c.  */
465 
pci_iounmap(struct pci_dev * dev,void __iomem * addr)466 void pci_iounmap(struct pci_dev *dev, void __iomem * addr)
467 {
468 	if (__is_mmio(addr))
469 		iounmap(addr);
470 }
471 
472 EXPORT_SYMBOL(pci_iounmap);
473 
474 /* FIXME: Some boxes have multiple ISA bridges! */
475 struct pci_dev *isa_bridge;
476 EXPORT_SYMBOL(isa_bridge);
477