xref: /openbmc/linux/arch/arm/mach-orion5x/pci.c (revision 384740dc)
1 /*
2  * arch/arm/mach-orion5x/pci.c
3  *
4  * PCI and PCIe functions for Marvell Orion System On Chip
5  *
6  * Maintainer: Tzachi Perelstein <tzachi@marvell.com>
7  *
8  * This file is licensed under the terms of the GNU General Public
9  * License version 2.  This program is licensed "as is" without any
10  * warranty of any kind, whether express or implied.
11  */
12 
13 #include <linux/kernel.h>
14 #include <linux/pci.h>
15 #include <linux/mbus.h>
16 #include <asm/mach/pci.h>
17 #include <plat/pcie.h>
18 #include "common.h"
19 
20 /*****************************************************************************
21  * Orion has one PCIe controller and one PCI controller.
22  *
23  * Note1: The local PCIe bus number is '0'. The local PCI bus number
24  * follows the scanned PCIe bridged busses, if any.
25  *
26  * Note2: It is possible for PCI/PCIe agents to access many subsystem's
27  * space, by configuring BARs and Address Decode Windows, e.g. flashes on
28  * device bus, Orion registers, etc. However this code only enable the
29  * access to DDR banks.
30  ****************************************************************************/
31 
32 
33 /*****************************************************************************
34  * PCIe controller
35  ****************************************************************************/
36 #define PCIE_BASE	((void __iomem *)ORION5X_PCIE_VIRT_BASE)
37 
38 void __init orion5x_pcie_id(u32 *dev, u32 *rev)
39 {
40 	*dev = orion_pcie_dev_id(PCIE_BASE);
41 	*rev = orion_pcie_rev(PCIE_BASE);
42 }
43 
44 static int pcie_valid_config(int bus, int dev)
45 {
46 	/*
47 	 * Don't go out when trying to access --
48 	 * 1. nonexisting device on local bus
49 	 * 2. where there's no device connected (no link)
50 	 */
51 	if (bus == 0 && dev == 0)
52 		return 1;
53 
54 	if (!orion_pcie_link_up(PCIE_BASE))
55 		return 0;
56 
57 	if (bus == 0 && dev != 1)
58 		return 0;
59 
60 	return 1;
61 }
62 
63 
64 /*
65  * PCIe config cycles are done by programming the PCIE_CONF_ADDR register
66  * and then reading the PCIE_CONF_DATA register. Need to make sure these
67  * transactions are atomic.
68  */
69 static DEFINE_SPINLOCK(orion5x_pcie_lock);
70 
71 static int pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
72 			int size, u32 *val)
73 {
74 	unsigned long flags;
75 	int ret;
76 
77 	if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0) {
78 		*val = 0xffffffff;
79 		return PCIBIOS_DEVICE_NOT_FOUND;
80 	}
81 
82 	spin_lock_irqsave(&orion5x_pcie_lock, flags);
83 	ret = orion_pcie_rd_conf(PCIE_BASE, bus, devfn, where, size, val);
84 	spin_unlock_irqrestore(&orion5x_pcie_lock, flags);
85 
86 	return ret;
87 }
88 
89 static int pcie_rd_conf_wa(struct pci_bus *bus, u32 devfn,
90 			   int where, int size, u32 *val)
91 {
92 	int ret;
93 
94 	if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0) {
95 		*val = 0xffffffff;
96 		return PCIBIOS_DEVICE_NOT_FOUND;
97 	}
98 
99 	/*
100 	 * We only support access to the non-extended configuration
101 	 * space when using the WA access method (or we would have to
102 	 * sacrifice 256M of CPU virtual address space.)
103 	 */
104 	if (where >= 0x100) {
105 		*val = 0xffffffff;
106 		return PCIBIOS_DEVICE_NOT_FOUND;
107 	}
108 
109 	ret = orion_pcie_rd_conf_wa((void __iomem *)ORION5X_PCIE_WA_VIRT_BASE,
110 				    bus, devfn, where, size, val);
111 
112 	return ret;
113 }
114 
115 static int pcie_wr_conf(struct pci_bus *bus, u32 devfn,
116 			int where, int size, u32 val)
117 {
118 	unsigned long flags;
119 	int ret;
120 
121 	if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0)
122 		return PCIBIOS_DEVICE_NOT_FOUND;
123 
124 	spin_lock_irqsave(&orion5x_pcie_lock, flags);
125 	ret = orion_pcie_wr_conf(PCIE_BASE, bus, devfn, where, size, val);
126 	spin_unlock_irqrestore(&orion5x_pcie_lock, flags);
127 
128 	return ret;
129 }
130 
131 static struct pci_ops pcie_ops = {
132 	.read = pcie_rd_conf,
133 	.write = pcie_wr_conf,
134 };
135 
136 
137 static int __init pcie_setup(struct pci_sys_data *sys)
138 {
139 	struct resource *res;
140 	int dev;
141 
142 	/*
143 	 * Generic PCIe unit setup.
144 	 */
145 	orion_pcie_setup(PCIE_BASE, &orion5x_mbus_dram_info);
146 
147 	/*
148 	 * Check whether to apply Orion-1/Orion-NAS PCIe config
149 	 * read transaction workaround.
150 	 */
151 	dev = orion_pcie_dev_id(PCIE_BASE);
152 	if (dev == MV88F5181_DEV_ID || dev == MV88F5182_DEV_ID) {
153 		printk(KERN_NOTICE "Applying Orion-1/Orion-NAS PCIe config "
154 				   "read transaction workaround\n");
155 		orion5x_setup_pcie_wa_win(ORION5X_PCIE_WA_PHYS_BASE,
156 					  ORION5X_PCIE_WA_SIZE);
157 		pcie_ops.read = pcie_rd_conf_wa;
158 	}
159 
160 	/*
161 	 * Request resources.
162 	 */
163 	res = kzalloc(sizeof(struct resource) * 2, GFP_KERNEL);
164 	if (!res)
165 		panic("pcie_setup unable to alloc resources");
166 
167 	/*
168 	 * IORESOURCE_IO
169 	 */
170 	res[0].name = "PCIe I/O Space";
171 	res[0].flags = IORESOURCE_IO;
172 	res[0].start = ORION5X_PCIE_IO_BUS_BASE;
173 	res[0].end = res[0].start + ORION5X_PCIE_IO_SIZE - 1;
174 	if (request_resource(&ioport_resource, &res[0]))
175 		panic("Request PCIe IO resource failed\n");
176 	sys->resource[0] = &res[0];
177 
178 	/*
179 	 * IORESOURCE_MEM
180 	 */
181 	res[1].name = "PCIe Memory Space";
182 	res[1].flags = IORESOURCE_MEM;
183 	res[1].start = ORION5X_PCIE_MEM_PHYS_BASE;
184 	res[1].end = res[1].start + ORION5X_PCIE_MEM_SIZE - 1;
185 	if (request_resource(&iomem_resource, &res[1]))
186 		panic("Request PCIe Memory resource failed\n");
187 	sys->resource[1] = &res[1];
188 
189 	sys->resource[2] = NULL;
190 	sys->io_offset = 0;
191 
192 	return 1;
193 }
194 
195 /*****************************************************************************
196  * PCI controller
197  ****************************************************************************/
198 #define PCI_MODE		ORION5X_PCI_REG(0xd00)
199 #define PCI_CMD			ORION5X_PCI_REG(0xc00)
200 #define PCI_P2P_CONF		ORION5X_PCI_REG(0x1d14)
201 #define PCI_CONF_ADDR		ORION5X_PCI_REG(0xc78)
202 #define PCI_CONF_DATA		ORION5X_PCI_REG(0xc7c)
203 
204 /*
205  * PCI_MODE bits
206  */
207 #define PCI_MODE_64BIT			(1 << 2)
208 #define PCI_MODE_PCIX			((1 << 4) | (1 << 5))
209 
210 /*
211  * PCI_CMD bits
212  */
213 #define PCI_CMD_HOST_REORDER		(1 << 29)
214 
215 /*
216  * PCI_P2P_CONF bits
217  */
218 #define PCI_P2P_BUS_OFFS		16
219 #define PCI_P2P_BUS_MASK		(0xff << PCI_P2P_BUS_OFFS)
220 #define PCI_P2P_DEV_OFFS		24
221 #define PCI_P2P_DEV_MASK		(0x1f << PCI_P2P_DEV_OFFS)
222 
223 /*
224  * PCI_CONF_ADDR bits
225  */
226 #define PCI_CONF_REG(reg)		((reg) & 0xfc)
227 #define PCI_CONF_FUNC(func)		(((func) & 0x3) << 8)
228 #define PCI_CONF_DEV(dev)		(((dev) & 0x1f) << 11)
229 #define PCI_CONF_BUS(bus)		(((bus) & 0xff) << 16)
230 #define PCI_CONF_ADDR_EN		(1 << 31)
231 
232 /*
233  * Internal configuration space
234  */
235 #define PCI_CONF_FUNC_STAT_CMD		0
236 #define PCI_CONF_REG_STAT_CMD		4
237 #define PCIX_STAT			0x64
238 #define PCIX_STAT_BUS_OFFS		8
239 #define PCIX_STAT_BUS_MASK		(0xff << PCIX_STAT_BUS_OFFS)
240 
241 /*
242  * PCI Address Decode Windows registers
243  */
244 #define PCI_BAR_SIZE_DDR_CS(n)	(((n) == 0) ? ORION5X_PCI_REG(0xc08) : \
245 				 ((n) == 1) ? ORION5X_PCI_REG(0xd08) : \
246 				 ((n) == 2) ? ORION5X_PCI_REG(0xc0c) : \
247 				 ((n) == 3) ? ORION5X_PCI_REG(0xd0c) : 0)
248 #define PCI_BAR_REMAP_DDR_CS(n)	(((n) == 0) ? ORION5X_PCI_REG(0xc48) : \
249 				 ((n) == 1) ? ORION5X_PCI_REG(0xd48) : \
250 				 ((n) == 2) ? ORION5X_PCI_REG(0xc4c) : \
251 				 ((n) == 3) ? ORION5X_PCI_REG(0xd4c) : 0)
252 #define PCI_BAR_ENABLE		ORION5X_PCI_REG(0xc3c)
253 #define PCI_ADDR_DECODE_CTRL	ORION5X_PCI_REG(0xd3c)
254 
255 /*
256  * PCI configuration helpers for BAR settings
257  */
258 #define PCI_CONF_FUNC_BAR_CS(n)		((n) >> 1)
259 #define PCI_CONF_REG_BAR_LO_CS(n)	(((n) & 1) ? 0x18 : 0x10)
260 #define PCI_CONF_REG_BAR_HI_CS(n)	(((n) & 1) ? 0x1c : 0x14)
261 
262 /*
263  * PCI config cycles are done by programming the PCI_CONF_ADDR register
264  * and then reading the PCI_CONF_DATA register. Need to make sure these
265  * transactions are atomic.
266  */
267 static DEFINE_SPINLOCK(orion5x_pci_lock);
268 
269 static int orion5x_pci_cardbus_mode;
270 
271 static int orion5x_pci_local_bus_nr(void)
272 {
273 	u32 conf = readl(PCI_P2P_CONF);
274 	return((conf & PCI_P2P_BUS_MASK) >> PCI_P2P_BUS_OFFS);
275 }
276 
277 static int orion5x_pci_hw_rd_conf(int bus, int dev, u32 func,
278 					u32 where, u32 size, u32 *val)
279 {
280 	unsigned long flags;
281 	spin_lock_irqsave(&orion5x_pci_lock, flags);
282 
283 	writel(PCI_CONF_BUS(bus) |
284 		PCI_CONF_DEV(dev) | PCI_CONF_REG(where) |
285 		PCI_CONF_FUNC(func) | PCI_CONF_ADDR_EN, PCI_CONF_ADDR);
286 
287 	*val = readl(PCI_CONF_DATA);
288 
289 	if (size == 1)
290 		*val = (*val >> (8*(where & 0x3))) & 0xff;
291 	else if (size == 2)
292 		*val = (*val >> (8*(where & 0x3))) & 0xffff;
293 
294 	spin_unlock_irqrestore(&orion5x_pci_lock, flags);
295 
296 	return PCIBIOS_SUCCESSFUL;
297 }
298 
299 static int orion5x_pci_hw_wr_conf(int bus, int dev, u32 func,
300 					u32 where, u32 size, u32 val)
301 {
302 	unsigned long flags;
303 	int ret = PCIBIOS_SUCCESSFUL;
304 
305 	spin_lock_irqsave(&orion5x_pci_lock, flags);
306 
307 	writel(PCI_CONF_BUS(bus) |
308 		PCI_CONF_DEV(dev) | PCI_CONF_REG(where) |
309 		PCI_CONF_FUNC(func) | PCI_CONF_ADDR_EN, PCI_CONF_ADDR);
310 
311 	if (size == 4) {
312 		__raw_writel(val, PCI_CONF_DATA);
313 	} else if (size == 2) {
314 		__raw_writew(val, PCI_CONF_DATA + (where & 0x3));
315 	} else if (size == 1) {
316 		__raw_writeb(val, PCI_CONF_DATA + (where & 0x3));
317 	} else {
318 		ret = PCIBIOS_BAD_REGISTER_NUMBER;
319 	}
320 
321 	spin_unlock_irqrestore(&orion5x_pci_lock, flags);
322 
323 	return ret;
324 }
325 
326 static int orion5x_pci_valid_config(int bus, u32 devfn)
327 {
328 	if (bus == orion5x_pci_local_bus_nr()) {
329 		/*
330 		 * Don't go out for local device
331 		 */
332 		if (PCI_SLOT(devfn) == 0 && PCI_FUNC(devfn) != 0)
333 			return 0;
334 
335 		/*
336 		 * When the PCI signals are directly connected to a
337 		 * Cardbus slot, ignore all but device IDs 0 and 1.
338 		 */
339 		if (orion5x_pci_cardbus_mode && PCI_SLOT(devfn) > 1)
340 			return 0;
341 	}
342 
343 	return 1;
344 }
345 
346 static int orion5x_pci_rd_conf(struct pci_bus *bus, u32 devfn,
347 				int where, int size, u32 *val)
348 {
349 	if (!orion5x_pci_valid_config(bus->number, devfn)) {
350 		*val = 0xffffffff;
351 		return PCIBIOS_DEVICE_NOT_FOUND;
352 	}
353 
354 	return orion5x_pci_hw_rd_conf(bus->number, PCI_SLOT(devfn),
355 					PCI_FUNC(devfn), where, size, val);
356 }
357 
358 static int orion5x_pci_wr_conf(struct pci_bus *bus, u32 devfn,
359 				int where, int size, u32 val)
360 {
361 	if (!orion5x_pci_valid_config(bus->number, devfn))
362 		return PCIBIOS_DEVICE_NOT_FOUND;
363 
364 	return orion5x_pci_hw_wr_conf(bus->number, PCI_SLOT(devfn),
365 					PCI_FUNC(devfn), where, size, val);
366 }
367 
368 static struct pci_ops pci_ops = {
369 	.read = orion5x_pci_rd_conf,
370 	.write = orion5x_pci_wr_conf,
371 };
372 
373 static void __init orion5x_pci_set_bus_nr(int nr)
374 {
375 	u32 p2p = readl(PCI_P2P_CONF);
376 
377 	if (readl(PCI_MODE) & PCI_MODE_PCIX) {
378 		/*
379 		 * PCI-X mode
380 		 */
381 		u32 pcix_status, bus, dev;
382 		bus = (p2p & PCI_P2P_BUS_MASK) >> PCI_P2P_BUS_OFFS;
383 		dev = (p2p & PCI_P2P_DEV_MASK) >> PCI_P2P_DEV_OFFS;
384 		orion5x_pci_hw_rd_conf(bus, dev, 0, PCIX_STAT, 4, &pcix_status);
385 		pcix_status &= ~PCIX_STAT_BUS_MASK;
386 		pcix_status |= (nr << PCIX_STAT_BUS_OFFS);
387 		orion5x_pci_hw_wr_conf(bus, dev, 0, PCIX_STAT, 4, pcix_status);
388 	} else {
389 		/*
390 		 * PCI Conventional mode
391 		 */
392 		p2p &= ~PCI_P2P_BUS_MASK;
393 		p2p |= (nr << PCI_P2P_BUS_OFFS);
394 		writel(p2p, PCI_P2P_CONF);
395 	}
396 }
397 
398 static void __init orion5x_pci_master_slave_enable(void)
399 {
400 	int bus_nr, func, reg;
401 	u32 val;
402 
403 	bus_nr = orion5x_pci_local_bus_nr();
404 	func = PCI_CONF_FUNC_STAT_CMD;
405 	reg = PCI_CONF_REG_STAT_CMD;
406 	orion5x_pci_hw_rd_conf(bus_nr, 0, func, reg, 4, &val);
407 	val |= (PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
408 	orion5x_pci_hw_wr_conf(bus_nr, 0, func, reg, 4, val | 0x7);
409 }
410 
411 static void __init orion5x_setup_pci_wins(struct mbus_dram_target_info *dram)
412 {
413 	u32 win_enable;
414 	int bus;
415 	int i;
416 
417 	/*
418 	 * First, disable windows.
419 	 */
420 	win_enable = 0xffffffff;
421 	writel(win_enable, PCI_BAR_ENABLE);
422 
423 	/*
424 	 * Setup windows for DDR banks.
425 	 */
426 	bus = orion5x_pci_local_bus_nr();
427 
428 	for (i = 0; i < dram->num_cs; i++) {
429 		struct mbus_dram_window *cs = dram->cs + i;
430 		u32 func = PCI_CONF_FUNC_BAR_CS(cs->cs_index);
431 		u32 reg;
432 		u32 val;
433 
434 		/*
435 		 * Write DRAM bank base address register.
436 		 */
437 		reg = PCI_CONF_REG_BAR_LO_CS(cs->cs_index);
438 		orion5x_pci_hw_rd_conf(bus, 0, func, reg, 4, &val);
439 		val = (cs->base & 0xfffff000) | (val & 0xfff);
440 		orion5x_pci_hw_wr_conf(bus, 0, func, reg, 4, val);
441 
442 		/*
443 		 * Write DRAM bank size register.
444 		 */
445 		reg = PCI_CONF_REG_BAR_HI_CS(cs->cs_index);
446 		orion5x_pci_hw_wr_conf(bus, 0, func, reg, 4, 0);
447 		writel((cs->size - 1) & 0xfffff000,
448 			PCI_BAR_SIZE_DDR_CS(cs->cs_index));
449 		writel(cs->base & 0xfffff000,
450 			PCI_BAR_REMAP_DDR_CS(cs->cs_index));
451 
452 		/*
453 		 * Enable decode window for this chip select.
454 		 */
455 		win_enable &= ~(1 << cs->cs_index);
456 	}
457 
458 	/*
459 	 * Re-enable decode windows.
460 	 */
461 	writel(win_enable, PCI_BAR_ENABLE);
462 
463 	/*
464 	 * Disable automatic update of address remaping when writing to BARs.
465 	 */
466 	orion5x_setbits(PCI_ADDR_DECODE_CTRL, 1);
467 }
468 
469 static int __init pci_setup(struct pci_sys_data *sys)
470 {
471 	struct resource *res;
472 
473 	/*
474 	 * Point PCI unit MBUS decode windows to DRAM space.
475 	 */
476 	orion5x_setup_pci_wins(&orion5x_mbus_dram_info);
477 
478 	/*
479 	 * Master + Slave enable
480 	 */
481 	orion5x_pci_master_slave_enable();
482 
483 	/*
484 	 * Force ordering
485 	 */
486 	orion5x_setbits(PCI_CMD, PCI_CMD_HOST_REORDER);
487 
488 	/*
489 	 * Request resources
490 	 */
491 	res = kzalloc(sizeof(struct resource) * 2, GFP_KERNEL);
492 	if (!res)
493 		panic("pci_setup unable to alloc resources");
494 
495 	/*
496 	 * IORESOURCE_IO
497 	 */
498 	res[0].name = "PCI I/O Space";
499 	res[0].flags = IORESOURCE_IO;
500 	res[0].start = ORION5X_PCI_IO_BUS_BASE;
501 	res[0].end = res[0].start + ORION5X_PCI_IO_SIZE - 1;
502 	if (request_resource(&ioport_resource, &res[0]))
503 		panic("Request PCI IO resource failed\n");
504 	sys->resource[0] = &res[0];
505 
506 	/*
507 	 * IORESOURCE_MEM
508 	 */
509 	res[1].name = "PCI Memory Space";
510 	res[1].flags = IORESOURCE_MEM;
511 	res[1].start = ORION5X_PCI_MEM_PHYS_BASE;
512 	res[1].end = res[1].start + ORION5X_PCI_MEM_SIZE - 1;
513 	if (request_resource(&iomem_resource, &res[1]))
514 		panic("Request PCI Memory resource failed\n");
515 	sys->resource[1] = &res[1];
516 
517 	sys->resource[2] = NULL;
518 	sys->io_offset = 0;
519 
520 	return 1;
521 }
522 
523 
524 /*****************************************************************************
525  * General PCIe + PCI
526  ****************************************************************************/
527 static void __devinit rc_pci_fixup(struct pci_dev *dev)
528 {
529 	/*
530 	 * Prevent enumeration of root complex.
531 	 */
532 	if (dev->bus->parent == NULL && dev->devfn == 0) {
533 		int i;
534 
535 		for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
536 			dev->resource[i].start = 0;
537 			dev->resource[i].end   = 0;
538 			dev->resource[i].flags = 0;
539 		}
540 	}
541 }
542 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MARVELL, PCI_ANY_ID, rc_pci_fixup);
543 
544 static int orion5x_pci_disabled __initdata;
545 
546 void __init orion5x_pci_disable(void)
547 {
548 	orion5x_pci_disabled = 1;
549 }
550 
551 void __init orion5x_pci_set_cardbus_mode(void)
552 {
553 	orion5x_pci_cardbus_mode = 1;
554 }
555 
556 int __init orion5x_pci_sys_setup(int nr, struct pci_sys_data *sys)
557 {
558 	int ret = 0;
559 
560 	if (nr == 0) {
561 		orion_pcie_set_local_bus_nr(PCIE_BASE, sys->busnr);
562 		ret = pcie_setup(sys);
563 	} else if (nr == 1 && !orion5x_pci_disabled) {
564 		orion5x_pci_set_bus_nr(sys->busnr);
565 		ret = pci_setup(sys);
566 	}
567 
568 	return ret;
569 }
570 
571 struct pci_bus __init *orion5x_pci_sys_scan_bus(int nr, struct pci_sys_data *sys)
572 {
573 	struct pci_bus *bus;
574 
575 	if (nr == 0) {
576 		bus = pci_scan_bus(sys->busnr, &pcie_ops, sys);
577 	} else if (nr == 1 && !orion5x_pci_disabled) {
578 		bus = pci_scan_bus(sys->busnr, &pci_ops, sys);
579 	} else {
580 		bus = NULL;
581 		BUG();
582 	}
583 
584 	return bus;
585 }
586 
587 int __init orion5x_pci_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
588 {
589 	int bus = dev->bus->number;
590 
591 	/*
592 	 * PCIe endpoint?
593 	 */
594 	if (orion5x_pci_disabled || bus < orion5x_pci_local_bus_nr())
595 		return IRQ_ORION5X_PCIE0_INT;
596 
597 	return -1;
598 }
599