1/*
2 * Broadcom specific AMBA
3 * PCI Core in hostmode
4 *
5 * Copyright 2005 - 2011, Broadcom Corporation
6 * Copyright 2006, 2007, Michael Buesch <m@bues.ch>
7 * Copyright 2011, 2012, Hauke Mehrtens <hauke@hauke-m.de>
8 *
9 * Licensed under the GNU/GPL. See COPYING for details.
10 */
11
12#include "bcma_private.h"
13#include <linux/pci.h>
14#include <linux/export.h>
15#include <linux/bcma/bcma.h>
16#include <asm/paccess.h>
17
18/* Probe a 32bit value on the bus and catch bus exceptions.
19 * Returns nonzero on a bus exception.
20 * This is MIPS specific */
21#define mips_busprobe32(val, addr)	get_dbe((val), ((u32 *)(addr)))
22
23/* Assume one-hot slot wiring */
24#define BCMA_PCI_SLOT_MAX	16
25#define	PCI_CONFIG_SPACE_SIZE	256
26
27bool __devinit bcma_core_pci_is_in_hostmode(struct bcma_drv_pci *pc)
28{
29	struct bcma_bus *bus = pc->core->bus;
30	u16 chipid_top;
31	u32 tmp;
32
33	chipid_top = (bus->chipinfo.id & 0xFF00);
34	if (chipid_top != 0x4700 &&
35	    chipid_top != 0x5300)
36		return false;
37
38	if (bus->sprom.boardflags_lo & BCMA_CORE_PCI_BFL_NOPCI) {
39		pr_info("This PCI core is disabled and not working\n");
40		return false;
41	}
42
43	bcma_core_enable(pc->core, 0);
44
45	return !mips_busprobe32(tmp, pc->core->io_addr);
46}
47
48static u32 bcma_pcie_read_config(struct bcma_drv_pci *pc, u32 address)
49{
50	pcicore_write32(pc, BCMA_CORE_PCI_CONFIG_ADDR, address);
51	pcicore_read32(pc, BCMA_CORE_PCI_CONFIG_ADDR);
52	return pcicore_read32(pc, BCMA_CORE_PCI_CONFIG_DATA);
53}
54
55static void bcma_pcie_write_config(struct bcma_drv_pci *pc, u32 address,
56				   u32 data)
57{
58	pcicore_write32(pc, BCMA_CORE_PCI_CONFIG_ADDR, address);
59	pcicore_read32(pc, BCMA_CORE_PCI_CONFIG_ADDR);
60	pcicore_write32(pc, BCMA_CORE_PCI_CONFIG_DATA, data);
61}
62
63static u32 bcma_get_cfgspace_addr(struct bcma_drv_pci *pc, unsigned int dev,
64			     unsigned int func, unsigned int off)
65{
66	u32 addr = 0;
67
68	/* Issue config commands only when the data link is up (atleast
69	 * one external pcie device is present).
70	 */
71	if (dev >= 2 || !(bcma_pcie_read(pc, BCMA_CORE_PCI_DLLP_LSREG)
72			  & BCMA_CORE_PCI_DLLP_LSREG_LINKUP))
73		goto out;
74
75	/* Type 0 transaction */
76	/* Slide the PCI window to the appropriate slot */
77	pcicore_write32(pc, BCMA_CORE_PCI_SBTOPCI1, BCMA_CORE_PCI_SBTOPCI_CFG0);
78	/* Calculate the address */
79	addr = pc->host_controller->host_cfg_addr;
80	addr |= (dev << BCMA_CORE_PCI_CFG_SLOT_SHIFT);
81	addr |= (func << BCMA_CORE_PCI_CFG_FUN_SHIFT);
82	addr |= (off & ~3);
83
84out:
85	return addr;
86}
87
88static int bcma_extpci_read_config(struct bcma_drv_pci *pc, unsigned int dev,
89				  unsigned int func, unsigned int off,
90				  void *buf, int len)
91{
92	int err = -EINVAL;
93	u32 addr, val;
94	void __iomem *mmio = 0;
95
96	WARN_ON(!pc->hostmode);
97	if (unlikely(len != 1 && len != 2 && len != 4))
98		goto out;
99	if (dev == 0) {
100		/* we support only two functions on device 0 */
101		if (func > 1)
102			return -EINVAL;
103
104		/* accesses to config registers with offsets >= 256
105		 * requires indirect access.
106		 */
107		if (off >= PCI_CONFIG_SPACE_SIZE) {
108			addr = (func << 12);
109			addr |= (off & 0x0FFF);
110			val = bcma_pcie_read_config(pc, addr);
111		} else {
112			addr = BCMA_CORE_PCI_PCICFG0;
113			addr |= (func << 8);
114			addr |= (off & 0xfc);
115			val = pcicore_read32(pc, addr);
116		}
117	} else {
118		addr = bcma_get_cfgspace_addr(pc, dev, func, off);
119		if (unlikely(!addr))
120			goto out;
121		err = -ENOMEM;
122		mmio = ioremap_nocache(addr, len);
123		if (!mmio)
124			goto out;
125
126		if (mips_busprobe32(val, mmio)) {
127			val = 0xffffffff;
128			goto unmap;
129		}
130
131		val = readl(mmio);
132	}
133	val >>= (8 * (off & 3));
134
135	switch (len) {
136	case 1:
137		*((u8 *)buf) = (u8)val;
138		break;
139	case 2:
140		*((u16 *)buf) = (u16)val;
141		break;
142	case 4:
143		*((u32 *)buf) = (u32)val;
144		break;
145	}
146	err = 0;
147unmap:
148	if (mmio)
149		iounmap(mmio);
150out:
151	return err;
152}
153
154static int bcma_extpci_write_config(struct bcma_drv_pci *pc, unsigned int dev,
155				   unsigned int func, unsigned int off,
156				   const void *buf, int len)
157{
158	int err = -EINVAL;
159	u32 addr = 0, val = 0;
160	void __iomem *mmio = 0;
161	u16 chipid = pc->core->bus->chipinfo.id;
162
163	WARN_ON(!pc->hostmode);
164	if (unlikely(len != 1 && len != 2 && len != 4))
165		goto out;
166	if (dev == 0) {
167		/* accesses to config registers with offsets >= 256
168		 * requires indirect access.
169		 */
170		if (off < PCI_CONFIG_SPACE_SIZE) {
171			addr = pc->core->addr + BCMA_CORE_PCI_PCICFG0;
172			addr |= (func << 8);
173			addr |= (off & 0xfc);
174			mmio = ioremap_nocache(addr, len);
175			if (!mmio)
176				goto out;
177		}
178	} else {
179		addr = bcma_get_cfgspace_addr(pc, dev, func, off);
180		if (unlikely(!addr))
181			goto out;
182		err = -ENOMEM;
183		mmio = ioremap_nocache(addr, len);
184		if (!mmio)
185			goto out;
186
187		if (mips_busprobe32(val, mmio)) {
188			val = 0xffffffff;
189			goto unmap;
190		}
191	}
192
193	switch (len) {
194	case 1:
195		val = readl(mmio);
196		val &= ~(0xFF << (8 * (off & 3)));
197		val |= *((const u8 *)buf) << (8 * (off & 3));
198		break;
199	case 2:
200		val = readl(mmio);
201		val &= ~(0xFFFF << (8 * (off & 3)));
202		val |= *((const u16 *)buf) << (8 * (off & 3));
203		break;
204	case 4:
205		val = *((const u32 *)buf);
206		break;
207	}
208	if (dev == 0 && !addr) {
209		/* accesses to config registers with offsets >= 256
210		 * requires indirect access.
211		 */
212		addr = (func << 12);
213		addr |= (off & 0x0FFF);
214		bcma_pcie_write_config(pc, addr, val);
215	} else {
216		writel(val, mmio);
217
218		if (chipid == 0x4716 || chipid == 0x4748)
219			readl(mmio);
220	}
221
222	err = 0;
223unmap:
224	if (mmio)
225		iounmap(mmio);
226out:
227	return err;
228}
229
230static int bcma_core_pci_hostmode_read_config(struct pci_bus *bus,
231					      unsigned int devfn,
232					      int reg, int size, u32 *val)
233{
234	unsigned long flags;
235	int err;
236	struct bcma_drv_pci *pc;
237	struct bcma_drv_pci_host *pc_host;
238
239	pc_host = container_of(bus->ops, struct bcma_drv_pci_host, pci_ops);
240	pc = pc_host->pdev;
241
242	spin_lock_irqsave(&pc_host->cfgspace_lock, flags);
243	err = bcma_extpci_read_config(pc, PCI_SLOT(devfn),
244				     PCI_FUNC(devfn), reg, val, size);
245	spin_unlock_irqrestore(&pc_host->cfgspace_lock, flags);
246
247	return err ? PCIBIOS_DEVICE_NOT_FOUND : PCIBIOS_SUCCESSFUL;
248}
249
250static int bcma_core_pci_hostmode_write_config(struct pci_bus *bus,
251					       unsigned int devfn,
252					       int reg, int size, u32 val)
253{
254	unsigned long flags;
255	int err;
256	struct bcma_drv_pci *pc;
257	struct bcma_drv_pci_host *pc_host;
258
259	pc_host = container_of(bus->ops, struct bcma_drv_pci_host, pci_ops);
260	pc = pc_host->pdev;
261
262	spin_lock_irqsave(&pc_host->cfgspace_lock, flags);
263	err = bcma_extpci_write_config(pc, PCI_SLOT(devfn),
264				      PCI_FUNC(devfn), reg, &val, size);
265	spin_unlock_irqrestore(&pc_host->cfgspace_lock, flags);
266
267	return err ? PCIBIOS_DEVICE_NOT_FOUND : PCIBIOS_SUCCESSFUL;
268}
269
270/* return cap_offset if requested capability exists in the PCI config space */
271static u8 __devinit bcma_find_pci_capability(struct bcma_drv_pci *pc,
272					     unsigned int dev,
273					     unsigned int func, u8 req_cap_id,
274					     unsigned char *buf, u32 *buflen)
275{
276	u8 cap_id;
277	u8 cap_ptr = 0;
278	u32 bufsize;
279	u8 byte_val;
280
281	/* check for Header type 0 */
282	bcma_extpci_read_config(pc, dev, func, PCI_HEADER_TYPE, &byte_val,
283				sizeof(u8));
284	if ((byte_val & 0x7f) != PCI_HEADER_TYPE_NORMAL)
285		return cap_ptr;
286
287	/* check if the capability pointer field exists */
288	bcma_extpci_read_config(pc, dev, func, PCI_STATUS, &byte_val,
289				sizeof(u8));
290	if (!(byte_val & PCI_STATUS_CAP_LIST))
291		return cap_ptr;
292
293	/* check if the capability pointer is 0x00 */
294	bcma_extpci_read_config(pc, dev, func, PCI_CAPABILITY_LIST, &cap_ptr,
295				sizeof(u8));
296	if (cap_ptr == 0x00)
297		return cap_ptr;
298
299	/* loop thr'u the capability list and see if the requested capabilty
300	 * exists */
301	bcma_extpci_read_config(pc, dev, func, cap_ptr, &cap_id, sizeof(u8));
302	while (cap_id != req_cap_id) {
303		bcma_extpci_read_config(pc, dev, func, cap_ptr + 1, &cap_ptr,
304					sizeof(u8));
305		if (cap_ptr == 0x00)
306			return cap_ptr;
307		bcma_extpci_read_config(pc, dev, func, cap_ptr, &cap_id,
308					sizeof(u8));
309	}
310
311	/* found the caller requested capability */
312	if ((buf != NULL) && (buflen != NULL)) {
313		u8 cap_data;
314
315		bufsize = *buflen;
316		if (!bufsize)
317			return cap_ptr;
318
319		*buflen = 0;
320
321		/* copy the cpability data excluding cap ID and next ptr */
322		cap_data = cap_ptr + 2;
323		if ((bufsize + cap_data)  > PCI_CONFIG_SPACE_SIZE)
324			bufsize = PCI_CONFIG_SPACE_SIZE - cap_data;
325		*buflen = bufsize;
326		while (bufsize--) {
327			bcma_extpci_read_config(pc, dev, func, cap_data, buf,
328						sizeof(u8));
329			cap_data++;
330			buf++;
331		}
332	}
333
334	return cap_ptr;
335}
336
337/* If the root port is capable of returning Config Request
338 * Retry Status (CRS) Completion Status to software then
339 * enable the feature.
340 */
341static void __devinit bcma_core_pci_enable_crs(struct bcma_drv_pci *pc)
342{
343	u8 cap_ptr, root_ctrl, root_cap, dev;
344	u16 val16;
345	int i;
346
347	cap_ptr = bcma_find_pci_capability(pc, 0, 0, PCI_CAP_ID_EXP, NULL,
348					   NULL);
349	root_cap = cap_ptr + PCI_EXP_RTCAP;
350	bcma_extpci_read_config(pc, 0, 0, root_cap, &val16, sizeof(u16));
351	if (val16 & BCMA_CORE_PCI_RC_CRS_VISIBILITY) {
352		/* Enable CRS software visibility */
353		root_ctrl = cap_ptr + PCI_EXP_RTCTL;
354		val16 = PCI_EXP_RTCTL_CRSSVE;
355		bcma_extpci_read_config(pc, 0, 0, root_ctrl, &val16,
356					sizeof(u16));
357
358		/* Initiate a configuration request to read the vendor id
359		 * field of the device function's config space header after
360		 * 100 ms wait time from the end of Reset. If the device is
361		 * not done with its internal initialization, it must at
362		 * least return a completion TLP, with a completion status
363		 * of "Configuration Request Retry Status (CRS)". The root
364		 * complex must complete the request to the host by returning
365		 * a read-data value of 0001h for the Vendor ID field and
366		 * all 1s for any additional bytes included in the request.
367		 * Poll using the config reads for max wait time of 1 sec or
368		 * until we receive the successful completion status. Repeat
369		 * the procedure for all the devices.
370		 */
371		for (dev = 1; dev < BCMA_PCI_SLOT_MAX; dev++) {
372			for (i = 0; i < 100000; i++) {
373				bcma_extpci_read_config(pc, dev, 0,
374							PCI_VENDOR_ID, &val16,
375							sizeof(val16));
376				if (val16 != 0x1)
377					break;
378				udelay(10);
379			}
380			if (val16 == 0x1)
381				pr_err("PCI: Broken device in slot %d\n", dev);
382		}
383	}
384}
385
386void __devinit bcma_core_pci_hostmode_init(struct bcma_drv_pci *pc)
387{
388	struct bcma_bus *bus = pc->core->bus;
389	struct bcma_drv_pci_host *pc_host;
390	u32 tmp;
391	u32 pci_membase_1G;
392	unsigned long io_map_base;
393
394	pr_info("PCIEcore in host mode found\n");
395
396	pc_host = kzalloc(sizeof(*pc_host), GFP_KERNEL);
397	if (!pc_host)  {
398		pr_err("can not allocate memory");
399		return;
400	}
401
402	pc->host_controller = pc_host;
403	pc_host->pci_controller.io_resource = &pc_host->io_resource;
404	pc_host->pci_controller.mem_resource = &pc_host->mem_resource;
405	pc_host->pci_controller.pci_ops = &pc_host->pci_ops;
406	pc_host->pdev = pc;
407
408	pci_membase_1G = BCMA_SOC_PCI_DMA;
409	pc_host->host_cfg_addr = BCMA_SOC_PCI_CFG;
410
411	pc_host->pci_ops.read = bcma_core_pci_hostmode_read_config;
412	pc_host->pci_ops.write = bcma_core_pci_hostmode_write_config;
413
414	pc_host->mem_resource.name = "BCMA PCIcore external memory",
415	pc_host->mem_resource.start = BCMA_SOC_PCI_DMA;
416	pc_host->mem_resource.end = BCMA_SOC_PCI_DMA + BCMA_SOC_PCI_DMA_SZ - 1;
417	pc_host->mem_resource.flags = IORESOURCE_MEM | IORESOURCE_PCI_FIXED;
418
419	pc_host->io_resource.name = "BCMA PCIcore external I/O",
420	pc_host->io_resource.start = 0x100;
421	pc_host->io_resource.end = 0x7FF;
422	pc_host->io_resource.flags = IORESOURCE_IO | IORESOURCE_PCI_FIXED;
423
424	/* Reset RC */
425	udelay(3000);
426	pcicore_write32(pc, BCMA_CORE_PCI_CTL, BCMA_CORE_PCI_CTL_RST_OE);
427	udelay(1000);
428	pcicore_write32(pc, BCMA_CORE_PCI_CTL, BCMA_CORE_PCI_CTL_RST |
429			BCMA_CORE_PCI_CTL_RST_OE);
430
431	/* 64 MB I/O access window. On 4716, use
432	 * sbtopcie0 to access the device registers. We
433	 * can't use address match 2 (1 GB window) region
434	 * as mips can't generate 64-bit address on the
435	 * backplane.
436	 */
437	if (bus->chipinfo.id == 0x4716 || bus->chipinfo.id == 0x4748) {
438		pc_host->mem_resource.start = BCMA_SOC_PCI_MEM;
439		pc_host->mem_resource.end = BCMA_SOC_PCI_MEM +
440					    BCMA_SOC_PCI_MEM_SZ - 1;
441		pcicore_write32(pc, BCMA_CORE_PCI_SBTOPCI0,
442				BCMA_CORE_PCI_SBTOPCI_MEM | BCMA_SOC_PCI_MEM);
443	} else if (bus->chipinfo.id == 0x5300) {
444		tmp = BCMA_CORE_PCI_SBTOPCI_MEM;
445		tmp |= BCMA_CORE_PCI_SBTOPCI_PREF;
446		tmp |= BCMA_CORE_PCI_SBTOPCI_BURST;
447		if (pc->core->core_unit == 0) {
448			pc_host->mem_resource.start = BCMA_SOC_PCI_MEM;
449			pc_host->mem_resource.end = BCMA_SOC_PCI_MEM +
450						    BCMA_SOC_PCI_MEM_SZ - 1;
451			pci_membase_1G = BCMA_SOC_PCIE_DMA_H32;
452			pcicore_write32(pc, BCMA_CORE_PCI_SBTOPCI0,
453					tmp | BCMA_SOC_PCI_MEM);
454		} else if (pc->core->core_unit == 1) {
455			pc_host->mem_resource.start = BCMA_SOC_PCI1_MEM;
456			pc_host->mem_resource.end = BCMA_SOC_PCI1_MEM +
457						    BCMA_SOC_PCI_MEM_SZ - 1;
458			pci_membase_1G = BCMA_SOC_PCIE1_DMA_H32;
459			pc_host->host_cfg_addr = BCMA_SOC_PCI1_CFG;
460			pcicore_write32(pc, BCMA_CORE_PCI_SBTOPCI0,
461					tmp | BCMA_SOC_PCI1_MEM);
462		}
463	} else
464		pcicore_write32(pc, BCMA_CORE_PCI_SBTOPCI0,
465				BCMA_CORE_PCI_SBTOPCI_IO);
466
467	/* 64 MB configuration access window */
468	pcicore_write32(pc, BCMA_CORE_PCI_SBTOPCI1, BCMA_CORE_PCI_SBTOPCI_CFG0);
469
470	/* 1 GB memory access window */
471	pcicore_write32(pc, BCMA_CORE_PCI_SBTOPCI2,
472			BCMA_CORE_PCI_SBTOPCI_MEM | pci_membase_1G);
473
474
475	/* As per PCI Express Base Spec 1.1 we need to wait for
476	 * at least 100 ms from the end of a reset (cold/warm/hot)
477	 * before issuing configuration requests to PCI Express
478	 * devices.
479	 */
480	udelay(100000);
481
482	bcma_core_pci_enable_crs(pc);
483
484	/* Enable PCI bridge BAR0 memory & master access */
485	tmp = PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY;
486	bcma_extpci_write_config(pc, 0, 0, PCI_COMMAND, &tmp, sizeof(tmp));
487
488	/* Enable PCI interrupts */
489	pcicore_write32(pc, BCMA_CORE_PCI_IMASK, BCMA_CORE_PCI_IMASK_INTA);
490
491	/* Ok, ready to run, register it to the system.
492	 * The following needs change, if we want to port hostmode
493	 * to non-MIPS platform. */
494	io_map_base = (unsigned long)ioremap_nocache(BCMA_SOC_PCI_MEM,
495						     0x04000000);
496	pc_host->pci_controller.io_map_base = io_map_base;
497	set_io_port_base(pc_host->pci_controller.io_map_base);
498	/* Give some time to the PCI controller to configure itself with the new
499	 * values. Not waiting at this point causes crashes of the machine. */
500	mdelay(10);
501	register_pci_controller(&pc_host->pci_controller);
502	return;
503}
504
505/* Early PCI fixup for a device on the PCI-core bridge. */
506static void bcma_core_pci_fixup_pcibridge(struct pci_dev *dev)
507{
508	if (dev->bus->ops->read != bcma_core_pci_hostmode_read_config) {
509		/* This is not a device on the PCI-core bridge. */
510		return;
511	}
512	if (PCI_SLOT(dev->devfn) != 0)
513		return;
514
515	pr_info("PCI: Fixing up bridge %s\n", pci_name(dev));
516
517	/* Enable PCI bridge bus mastering and memory space */
518	pci_set_master(dev);
519	if (pcibios_enable_device(dev, ~0) < 0) {
520		pr_err("PCI: BCMA bridge enable failed\n");
521		return;
522	}
523
524	/* Enable PCI bridge BAR1 prefetch and burst */
525	pci_write_config_dword(dev, BCMA_PCI_BAR1_CONTROL, 3);
526}
527DECLARE_PCI_FIXUP_EARLY(PCI_ANY_ID, PCI_ANY_ID, bcma_core_pci_fixup_pcibridge);
528
529/* Early PCI fixup for all PCI-cores to set the correct memory address. */
530static void bcma_core_pci_fixup_addresses(struct pci_dev *dev)
531{
532	struct resource *res;
533	int pos;
534
535	if (dev->bus->ops->read != bcma_core_pci_hostmode_read_config) {
536		/* This is not a device on the PCI-core bridge. */
537		return;
538	}
539	if (PCI_SLOT(dev->devfn) == 0)
540		return;
541
542	pr_info("PCI: Fixing up addresses %s\n", pci_name(dev));
543
544	for (pos = 0; pos < 6; pos++) {
545		res = &dev->resource[pos];
546		if (res->flags & (IORESOURCE_IO | IORESOURCE_MEM))
547			pci_assign_resource(dev, pos);
548	}
549}
550DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, bcma_core_pci_fixup_addresses);
551
552/* This function is called when doing a pci_enable_device().
553 * We must first check if the device is a device on the PCI-core bridge. */
554int bcma_core_pci_plat_dev_init(struct pci_dev *dev)
555{
556	struct bcma_drv_pci_host *pc_host;
557
558	if (dev->bus->ops->read != bcma_core_pci_hostmode_read_config) {
559		/* This is not a device on the PCI-core bridge. */
560		return -ENODEV;
561	}
562	pc_host = container_of(dev->bus->ops, struct bcma_drv_pci_host,
563			       pci_ops);
564
565	pr_info("PCI: Fixing up device %s\n", pci_name(dev));
566
567	/* Fix up interrupt lines */
568	dev->irq = bcma_core_mips_irq(pc_host->pdev->core) + 2;
569	pci_write_config_byte(dev, PCI_INTERRUPT_LINE, dev->irq);
570
571	return 0;
572}
573EXPORT_SYMBOL(bcma_core_pci_plat_dev_init);
574
575/* PCI device IRQ mapping. */
576int bcma_core_pci_pcibios_map_irq(const struct pci_dev *dev)
577{
578	struct bcma_drv_pci_host *pc_host;
579
580	if (dev->bus->ops->read != bcma_core_pci_hostmode_read_config) {
581		/* This is not a device on the PCI-core bridge. */
582		return -ENODEV;
583	}
584
585	pc_host = container_of(dev->bus->ops, struct bcma_drv_pci_host,
586			       pci_ops);
587	return bcma_core_mips_irq(pc_host->pdev->core) + 2;
588}
589EXPORT_SYMBOL(bcma_core_pci_pcibios_map_irq);
590