xref: /openbmc/linux/arch/arm/kernel/bios32.c (revision eb3fcf00)
1 /*
2  *  linux/arch/arm/kernel/bios32.c
3  *
4  *  PCI bios-type initialisation for PCI machines
5  *
6  *  Bits taken from various places.
7  */
8 #include <linux/export.h>
9 #include <linux/kernel.h>
10 #include <linux/pci.h>
11 #include <linux/slab.h>
12 #include <linux/init.h>
13 #include <linux/io.h>
14 
15 #include <asm/mach-types.h>
16 #include <asm/mach/map.h>
17 #include <asm/mach/pci.h>
18 
19 static int debug_pci;
20 
21 /*
22  * We can't use pci_get_device() here since we are
23  * called from interrupt context.
24  */
25 static void pcibios_bus_report_status(struct pci_bus *bus, u_int status_mask, int warn)
26 {
27 	struct pci_dev *dev;
28 
29 	list_for_each_entry(dev, &bus->devices, bus_list) {
30 		u16 status;
31 
32 		/*
33 		 * ignore host bridge - we handle
34 		 * that separately
35 		 */
36 		if (dev->bus->number == 0 && dev->devfn == 0)
37 			continue;
38 
39 		pci_read_config_word(dev, PCI_STATUS, &status);
40 		if (status == 0xffff)
41 			continue;
42 
43 		if ((status & status_mask) == 0)
44 			continue;
45 
46 		/* clear the status errors */
47 		pci_write_config_word(dev, PCI_STATUS, status & status_mask);
48 
49 		if (warn)
50 			printk("(%s: %04X) ", pci_name(dev), status);
51 	}
52 
53 	list_for_each_entry(dev, &bus->devices, bus_list)
54 		if (dev->subordinate)
55 			pcibios_bus_report_status(dev->subordinate, status_mask, warn);
56 }
57 
58 void pcibios_report_status(u_int status_mask, int warn)
59 {
60 	struct pci_bus *bus;
61 
62 	list_for_each_entry(bus, &pci_root_buses, node)
63 		pcibios_bus_report_status(bus, status_mask, warn);
64 }
65 
66 /*
67  * We don't use this to fix the device, but initialisation of it.
68  * It's not the correct use for this, but it works.
69  * Note that the arbiter/ISA bridge appears to be buggy, specifically in
70  * the following area:
71  * 1. park on CPU
72  * 2. ISA bridge ping-pong
73  * 3. ISA bridge master handling of target RETRY
74  *
75  * Bug 3 is responsible for the sound DMA grinding to a halt.  We now
76  * live with bug 2.
77  */
78 static void pci_fixup_83c553(struct pci_dev *dev)
79 {
80 	/*
81 	 * Set memory region to start at address 0, and enable IO
82 	 */
83 	pci_write_config_dword(dev, PCI_BASE_ADDRESS_0, PCI_BASE_ADDRESS_SPACE_MEMORY);
84 	pci_write_config_word(dev, PCI_COMMAND, PCI_COMMAND_IO);
85 
86 	dev->resource[0].end -= dev->resource[0].start;
87 	dev->resource[0].start = 0;
88 
89 	/*
90 	 * All memory requests from ISA to be channelled to PCI
91 	 */
92 	pci_write_config_byte(dev, 0x48, 0xff);
93 
94 	/*
95 	 * Enable ping-pong on bus master to ISA bridge transactions.
96 	 * This improves the sound DMA substantially.  The fixed
97 	 * priority arbiter also helps (see below).
98 	 */
99 	pci_write_config_byte(dev, 0x42, 0x01);
100 
101 	/*
102 	 * Enable PCI retry
103 	 */
104 	pci_write_config_byte(dev, 0x40, 0x22);
105 
106 	/*
107 	 * We used to set the arbiter to "park on last master" (bit
108 	 * 1 set), but unfortunately the CyberPro does not park the
109 	 * bus.  We must therefore park on CPU.  Unfortunately, this
110 	 * may trigger yet another bug in the 553.
111 	 */
112 	pci_write_config_byte(dev, 0x83, 0x02);
113 
114 	/*
115 	 * Make the ISA DMA request lowest priority, and disable
116 	 * rotating priorities completely.
117 	 */
118 	pci_write_config_byte(dev, 0x80, 0x11);
119 	pci_write_config_byte(dev, 0x81, 0x00);
120 
121 	/*
122 	 * Route INTA input to IRQ 11, and set IRQ11 to be level
123 	 * sensitive.
124 	 */
125 	pci_write_config_word(dev, 0x44, 0xb000);
126 	outb(0x08, 0x4d1);
127 }
128 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_WINBOND, PCI_DEVICE_ID_WINBOND_83C553, pci_fixup_83c553);
129 
130 static void pci_fixup_unassign(struct pci_dev *dev)
131 {
132 	dev->resource[0].end -= dev->resource[0].start;
133 	dev->resource[0].start = 0;
134 }
135 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_WINBOND2, PCI_DEVICE_ID_WINBOND2_89C940F, pci_fixup_unassign);
136 
137 /*
138  * Prevent the PCI layer from seeing the resources allocated to this device
139  * if it is the host bridge by marking it as such.  These resources are of
140  * no consequence to the PCI layer (they are handled elsewhere).
141  */
142 static void pci_fixup_dec21285(struct pci_dev *dev)
143 {
144 	int i;
145 
146 	if (dev->devfn == 0) {
147 		dev->class &= 0xff;
148 		dev->class |= PCI_CLASS_BRIDGE_HOST << 8;
149 		for (i = 0; i < PCI_NUM_RESOURCES; i++) {
150 			dev->resource[i].start = 0;
151 			dev->resource[i].end   = 0;
152 			dev->resource[i].flags = 0;
153 		}
154 	}
155 }
156 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_DEC, PCI_DEVICE_ID_DEC_21285, pci_fixup_dec21285);
157 
158 /*
159  * PCI IDE controllers use non-standard I/O port decoding, respect it.
160  */
161 static void pci_fixup_ide_bases(struct pci_dev *dev)
162 {
163 	struct resource *r;
164 	int i;
165 
166 	if ((dev->class >> 8) != PCI_CLASS_STORAGE_IDE)
167 		return;
168 
169 	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
170 		r = dev->resource + i;
171 		if ((r->start & ~0x80) == 0x374) {
172 			r->start |= 2;
173 			r->end = r->start;
174 		}
175 	}
176 }
177 DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, pci_fixup_ide_bases);
178 
179 /*
180  * Put the DEC21142 to sleep
181  */
182 static void pci_fixup_dec21142(struct pci_dev *dev)
183 {
184 	pci_write_config_dword(dev, 0x40, 0x80000000);
185 }
186 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_DEC, PCI_DEVICE_ID_DEC_21142, pci_fixup_dec21142);
187 
188 /*
189  * The CY82C693 needs some rather major fixups to ensure that it does
190  * the right thing.  Idea from the Alpha people, with a few additions.
191  *
192  * We ensure that the IDE base registers are set to 1f0/3f4 for the
193  * primary bus, and 170/374 for the secondary bus.  Also, hide them
194  * from the PCI subsystem view as well so we won't try to perform
195  * our own auto-configuration on them.
196  *
197  * In addition, we ensure that the PCI IDE interrupts are routed to
198  * IRQ 14 and IRQ 15 respectively.
199  *
200  * The above gets us to a point where the IDE on this device is
201  * functional.  However, The CY82C693U _does not work_ in bus
202  * master mode without locking the PCI bus solid.
203  */
204 static void pci_fixup_cy82c693(struct pci_dev *dev)
205 {
206 	if ((dev->class >> 8) == PCI_CLASS_STORAGE_IDE) {
207 		u32 base0, base1;
208 
209 		if (dev->class & 0x80) {	/* primary */
210 			base0 = 0x1f0;
211 			base1 = 0x3f4;
212 		} else {			/* secondary */
213 			base0 = 0x170;
214 			base1 = 0x374;
215 		}
216 
217 		pci_write_config_dword(dev, PCI_BASE_ADDRESS_0,
218 				       base0 | PCI_BASE_ADDRESS_SPACE_IO);
219 		pci_write_config_dword(dev, PCI_BASE_ADDRESS_1,
220 				       base1 | PCI_BASE_ADDRESS_SPACE_IO);
221 
222 		dev->resource[0].start = 0;
223 		dev->resource[0].end   = 0;
224 		dev->resource[0].flags = 0;
225 
226 		dev->resource[1].start = 0;
227 		dev->resource[1].end   = 0;
228 		dev->resource[1].flags = 0;
229 	} else if (PCI_FUNC(dev->devfn) == 0) {
230 		/*
231 		 * Setup IDE IRQ routing.
232 		 */
233 		pci_write_config_byte(dev, 0x4b, 14);
234 		pci_write_config_byte(dev, 0x4c, 15);
235 
236 		/*
237 		 * Disable FREQACK handshake, enable USB.
238 		 */
239 		pci_write_config_byte(dev, 0x4d, 0x41);
240 
241 		/*
242 		 * Enable PCI retry, and PCI post-write buffer.
243 		 */
244 		pci_write_config_byte(dev, 0x44, 0x17);
245 
246 		/*
247 		 * Enable ISA master and DMA post write buffering.
248 		 */
249 		pci_write_config_byte(dev, 0x45, 0x03);
250 	}
251 }
252 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_CONTAQ, PCI_DEVICE_ID_CONTAQ_82C693, pci_fixup_cy82c693);
253 
254 static void pci_fixup_it8152(struct pci_dev *dev)
255 {
256 	int i;
257 	/* fixup for ITE 8152 devices */
258 	/* FIXME: add defines for class 0x68000 and 0x80103 */
259 	if ((dev->class >> 8) == PCI_CLASS_BRIDGE_HOST ||
260 	    dev->class == 0x68000 ||
261 	    dev->class == 0x80103) {
262 		for (i = 0; i < PCI_NUM_RESOURCES; i++) {
263 			dev->resource[i].start = 0;
264 			dev->resource[i].end   = 0;
265 			dev->resource[i].flags = 0;
266 		}
267 	}
268 }
269 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ITE, PCI_DEVICE_ID_ITE_8152, pci_fixup_it8152);
270 
271 /*
272  * If the bus contains any of these devices, then we must not turn on
273  * parity checking of any kind.  Currently this is CyberPro 20x0 only.
274  */
275 static inline int pdev_bad_for_parity(struct pci_dev *dev)
276 {
277 	return ((dev->vendor == PCI_VENDOR_ID_INTERG &&
278 		 (dev->device == PCI_DEVICE_ID_INTERG_2000 ||
279 		  dev->device == PCI_DEVICE_ID_INTERG_2010)) ||
280 		(dev->vendor == PCI_VENDOR_ID_ITE &&
281 		 dev->device == PCI_DEVICE_ID_ITE_8152));
282 
283 }
284 
285 /*
286  * pcibios_fixup_bus - Called after each bus is probed,
287  * but before its children are examined.
288  */
289 void pcibios_fixup_bus(struct pci_bus *bus)
290 {
291 	struct pci_dev *dev;
292 	u16 features = PCI_COMMAND_SERR | PCI_COMMAND_PARITY | PCI_COMMAND_FAST_BACK;
293 
294 	/*
295 	 * Walk the devices on this bus, working out what we can
296 	 * and can't support.
297 	 */
298 	list_for_each_entry(dev, &bus->devices, bus_list) {
299 		u16 status;
300 
301 		pci_read_config_word(dev, PCI_STATUS, &status);
302 
303 		/*
304 		 * If any device on this bus does not support fast back
305 		 * to back transfers, then the bus as a whole is not able
306 		 * to support them.  Having fast back to back transfers
307 		 * on saves us one PCI cycle per transaction.
308 		 */
309 		if (!(status & PCI_STATUS_FAST_BACK))
310 			features &= ~PCI_COMMAND_FAST_BACK;
311 
312 		if (pdev_bad_for_parity(dev))
313 			features &= ~(PCI_COMMAND_SERR | PCI_COMMAND_PARITY);
314 
315 		switch (dev->class >> 8) {
316 		case PCI_CLASS_BRIDGE_PCI:
317 			pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &status);
318 			status |= PCI_BRIDGE_CTL_PARITY|PCI_BRIDGE_CTL_MASTER_ABORT;
319 			status &= ~(PCI_BRIDGE_CTL_BUS_RESET|PCI_BRIDGE_CTL_FAST_BACK);
320 			pci_write_config_word(dev, PCI_BRIDGE_CONTROL, status);
321 			break;
322 
323 		case PCI_CLASS_BRIDGE_CARDBUS:
324 			pci_read_config_word(dev, PCI_CB_BRIDGE_CONTROL, &status);
325 			status |= PCI_CB_BRIDGE_CTL_PARITY|PCI_CB_BRIDGE_CTL_MASTER_ABORT;
326 			pci_write_config_word(dev, PCI_CB_BRIDGE_CONTROL, status);
327 			break;
328 		}
329 	}
330 
331 	/*
332 	 * Now walk the devices again, this time setting them up.
333 	 */
334 	list_for_each_entry(dev, &bus->devices, bus_list) {
335 		u16 cmd;
336 
337 		pci_read_config_word(dev, PCI_COMMAND, &cmd);
338 		cmd |= features;
339 		pci_write_config_word(dev, PCI_COMMAND, cmd);
340 
341 		pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE,
342 				      L1_CACHE_BYTES >> 2);
343 	}
344 
345 	/*
346 	 * Propagate the flags to the PCI bridge.
347 	 */
348 	if (bus->self && bus->self->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
349 		if (features & PCI_COMMAND_FAST_BACK)
350 			bus->bridge_ctl |= PCI_BRIDGE_CTL_FAST_BACK;
351 		if (features & PCI_COMMAND_PARITY)
352 			bus->bridge_ctl |= PCI_BRIDGE_CTL_PARITY;
353 	}
354 
355 	/*
356 	 * Report what we did for this bus
357 	 */
358 	pr_info("PCI: bus%d: Fast back to back transfers %sabled\n",
359 		bus->number, (features & PCI_COMMAND_FAST_BACK) ? "en" : "dis");
360 }
361 EXPORT_SYMBOL(pcibios_fixup_bus);
362 
363 /*
364  * Swizzle the device pin each time we cross a bridge.  If a platform does
365  * not provide a swizzle function, we perform the standard PCI swizzling.
366  *
367  * The default swizzling walks up the bus tree one level at a time, applying
368  * the standard swizzle function at each step, stopping when it finds the PCI
369  * root bus.  This will return the slot number of the bridge device on the
370  * root bus and the interrupt pin on that device which should correspond
371  * with the downstream device interrupt.
372  *
373  * Platforms may override this, in which case the slot and pin returned
374  * depend entirely on the platform code.  However, please note that the
375  * PCI standard swizzle is implemented on plug-in cards and Cardbus based
376  * PCI extenders, so it can not be ignored.
377  */
378 static u8 pcibios_swizzle(struct pci_dev *dev, u8 *pin)
379 {
380 	struct pci_sys_data *sys = dev->sysdata;
381 	int slot, oldpin = *pin;
382 
383 	if (sys->swizzle)
384 		slot = sys->swizzle(dev, pin);
385 	else
386 		slot = pci_common_swizzle(dev, pin);
387 
388 	if (debug_pci)
389 		printk("PCI: %s swizzling pin %d => pin %d slot %d\n",
390 			pci_name(dev), oldpin, *pin, slot);
391 
392 	return slot;
393 }
394 
395 /*
396  * Map a slot/pin to an IRQ.
397  */
398 static int pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
399 {
400 	struct pci_sys_data *sys = dev->sysdata;
401 	int irq = -1;
402 
403 	if (sys->map_irq)
404 		irq = sys->map_irq(dev, slot, pin);
405 
406 	if (debug_pci)
407 		printk("PCI: %s mapping slot %d pin %d => irq %d\n",
408 			pci_name(dev), slot, pin, irq);
409 
410 	return irq;
411 }
412 
413 static int pcibios_init_resources(int busnr, struct pci_sys_data *sys)
414 {
415 	int ret;
416 	struct resource_entry *window;
417 
418 	if (list_empty(&sys->resources)) {
419 		pci_add_resource_offset(&sys->resources,
420 			 &iomem_resource, sys->mem_offset);
421 	}
422 
423 	resource_list_for_each_entry(window, &sys->resources)
424 		if (resource_type(window->res) == IORESOURCE_IO)
425 			return 0;
426 
427 	sys->io_res.start = (busnr * SZ_64K) ?  : pcibios_min_io;
428 	sys->io_res.end = (busnr + 1) * SZ_64K - 1;
429 	sys->io_res.flags = IORESOURCE_IO;
430 	sys->io_res.name = sys->io_res_name;
431 	sprintf(sys->io_res_name, "PCI%d I/O", busnr);
432 
433 	ret = request_resource(&ioport_resource, &sys->io_res);
434 	if (ret) {
435 		pr_err("PCI: unable to allocate I/O port region (%d)\n", ret);
436 		return ret;
437 	}
438 	pci_add_resource_offset(&sys->resources, &sys->io_res,
439 				sys->io_offset);
440 
441 	return 0;
442 }
443 
444 static void pcibios_init_hw(struct device *parent, struct hw_pci *hw,
445 			    struct list_head *head)
446 {
447 	struct pci_sys_data *sys = NULL;
448 	int ret;
449 	int nr, busnr;
450 
451 	for (nr = busnr = 0; nr < hw->nr_controllers; nr++) {
452 		sys = kzalloc(sizeof(struct pci_sys_data), GFP_KERNEL);
453 		if (WARN(!sys, "PCI: unable to allocate sys data!"))
454 			break;
455 
456 		sys->busnr   = busnr;
457 		sys->swizzle = hw->swizzle;
458 		sys->map_irq = hw->map_irq;
459 		sys->align_resource = hw->align_resource;
460 		INIT_LIST_HEAD(&sys->resources);
461 
462 		if (hw->private_data)
463 			sys->private_data = hw->private_data[nr];
464 
465 		ret = hw->setup(nr, sys);
466 
467 		if (ret > 0) {
468 			ret = pcibios_init_resources(nr, sys);
469 			if (ret)  {
470 				kfree(sys);
471 				break;
472 			}
473 
474 			if (hw->scan)
475 				sys->bus = hw->scan(nr, sys);
476 			else
477 				sys->bus = pci_scan_root_bus_msi(parent,
478 					sys->busnr, hw->ops, sys,
479 					&sys->resources, hw->msi_ctrl);
480 
481 			if (WARN(!sys->bus, "PCI: unable to scan bus!")) {
482 				kfree(sys);
483 				break;
484 			}
485 
486 			busnr = sys->bus->busn_res.end + 1;
487 
488 			list_add(&sys->node, head);
489 		} else {
490 			kfree(sys);
491 			if (ret < 0)
492 				break;
493 		}
494 	}
495 }
496 
497 void pci_common_init_dev(struct device *parent, struct hw_pci *hw)
498 {
499 	struct pci_sys_data *sys;
500 	LIST_HEAD(head);
501 
502 	pci_add_flags(PCI_REASSIGN_ALL_RSRC);
503 	if (hw->preinit)
504 		hw->preinit();
505 	pcibios_init_hw(parent, hw, &head);
506 	if (hw->postinit)
507 		hw->postinit();
508 
509 	pci_fixup_irqs(pcibios_swizzle, pcibios_map_irq);
510 
511 	list_for_each_entry(sys, &head, node) {
512 		struct pci_bus *bus = sys->bus;
513 
514 		if (!pci_has_flag(PCI_PROBE_ONLY)) {
515 			struct pci_bus *child;
516 
517 			/*
518 			 * Size the bridge windows.
519 			 */
520 			pci_bus_size_bridges(bus);
521 
522 			/*
523 			 * Assign resources.
524 			 */
525 			pci_bus_assign_resources(bus);
526 
527 			list_for_each_entry(child, &bus->children, node)
528 				pcie_bus_configure_settings(child);
529 		}
530 		/*
531 		 * Tell drivers about devices found.
532 		 */
533 		pci_bus_add_devices(bus);
534 	}
535 }
536 
537 #ifndef CONFIG_PCI_HOST_ITE8152
538 void pcibios_set_master(struct pci_dev *dev)
539 {
540 	/* No special bus mastering setup handling */
541 }
542 #endif
543 
544 char * __init pcibios_setup(char *str)
545 {
546 	if (!strcmp(str, "debug")) {
547 		debug_pci = 1;
548 		return NULL;
549 	} else if (!strcmp(str, "firmware")) {
550 		pci_add_flags(PCI_PROBE_ONLY);
551 		return NULL;
552 	}
553 	return str;
554 }
555 
556 /*
557  * From arch/i386/kernel/pci-i386.c:
558  *
559  * We need to avoid collisions with `mirrored' VGA ports
560  * and other strange ISA hardware, so we always want the
561  * addresses to be allocated in the 0x000-0x0ff region
562  * modulo 0x400.
563  *
564  * Why? Because some silly external IO cards only decode
565  * the low 10 bits of the IO address. The 0x00-0xff region
566  * is reserved for motherboard devices that decode all 16
567  * bits, so it's ok to allocate at, say, 0x2800-0x28ff,
568  * but we want to try to avoid allocating at 0x2900-0x2bff
569  * which might be mirrored at 0x0100-0x03ff..
570  */
571 resource_size_t pcibios_align_resource(void *data, const struct resource *res,
572 				resource_size_t size, resource_size_t align)
573 {
574 	struct pci_dev *dev = data;
575 	struct pci_sys_data *sys = dev->sysdata;
576 	resource_size_t start = res->start;
577 
578 	if (res->flags & IORESOURCE_IO && start & 0x300)
579 		start = (start + 0x3ff) & ~0x3ff;
580 
581 	start = (start + align - 1) & ~(align - 1);
582 
583 	if (sys->align_resource)
584 		return sys->align_resource(dev, res, start, size, align);
585 
586 	return start;
587 }
588 
589 /**
590  * pcibios_enable_device - Enable I/O and memory.
591  * @dev: PCI device to be enabled
592  */
593 int pcibios_enable_device(struct pci_dev *dev, int mask)
594 {
595 	if (pci_has_flag(PCI_PROBE_ONLY))
596 		return 0;
597 
598 	return pci_enable_resources(dev, mask);
599 }
600 
601 int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
602 			enum pci_mmap_state mmap_state, int write_combine)
603 {
604 	if (mmap_state == pci_mmap_io)
605 		return -EINVAL;
606 
607 	/*
608 	 * Mark this as IO
609 	 */
610 	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
611 
612 	if (remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
613 			     vma->vm_end - vma->vm_start,
614 			     vma->vm_page_prot))
615 		return -EAGAIN;
616 
617 	return 0;
618 }
619 
620 void __init pci_map_io_early(unsigned long pfn)
621 {
622 	struct map_desc pci_io_desc = {
623 		.virtual	= PCI_IO_VIRT_BASE,
624 		.type		= MT_DEVICE,
625 		.length		= SZ_64K,
626 	};
627 
628 	pci_io_desc.pfn = pfn;
629 	iotable_init(&pci_io_desc, 1);
630 }
631