xref: /openbmc/linux/arch/arm/mach-orion5x/pci.c (revision ff89c462)
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/irq.h>
17 #include <asm/mach/pci.h>
18 #include <plat/pcie.h>
19 #include "common.h"
20 
21 /*****************************************************************************
22  * Orion has one PCIe controller and one PCI controller.
23  *
24  * Note1: The local PCIe bus number is '0'. The local PCI bus number
25  * follows the scanned PCIe bridged busses, if any.
26  *
27  * Note2: It is possible for PCI/PCIe agents to access many subsystem's
28  * space, by configuring BARs and Address Decode Windows, e.g. flashes on
29  * device bus, Orion registers, etc. However this code only enable the
30  * access to DDR banks.
31  ****************************************************************************/
32 
33 
34 /*****************************************************************************
35  * PCIe controller
36  ****************************************************************************/
37 #define PCIE_BASE	((void __iomem *)ORION5X_PCIE_VIRT_BASE)
38 
39 void __init orion5x_pcie_id(u32 *dev, u32 *rev)
40 {
41 	*dev = orion_pcie_dev_id(PCIE_BASE);
42 	*rev = orion_pcie_rev(PCIE_BASE);
43 }
44 
45 static int pcie_valid_config(int bus, int dev)
46 {
47 	/*
48 	 * Don't go out when trying to access --
49 	 * 1. nonexisting device on local bus
50 	 * 2. where there's no device connected (no link)
51 	 */
52 	if (bus == 0 && dev == 0)
53 		return 1;
54 
55 	if (!orion_pcie_link_up(PCIE_BASE))
56 		return 0;
57 
58 	if (bus == 0 && dev != 1)
59 		return 0;
60 
61 	return 1;
62 }
63 
64 
65 /*
66  * PCIe config cycles are done by programming the PCIE_CONF_ADDR register
67  * and then reading the PCIE_CONF_DATA register. Need to make sure these
68  * transactions are atomic.
69  */
70 static DEFINE_SPINLOCK(orion5x_pcie_lock);
71 
72 static int pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
73 			int size, u32 *val)
74 {
75 	unsigned long flags;
76 	int ret;
77 
78 	if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0) {
79 		*val = 0xffffffff;
80 		return PCIBIOS_DEVICE_NOT_FOUND;
81 	}
82 
83 	spin_lock_irqsave(&orion5x_pcie_lock, flags);
84 	ret = orion_pcie_rd_conf(PCIE_BASE, bus, devfn, where, size, val);
85 	spin_unlock_irqrestore(&orion5x_pcie_lock, flags);
86 
87 	return ret;
88 }
89 
90 static int pcie_rd_conf_wa(struct pci_bus *bus, u32 devfn,
91 			   int where, int size, u32 *val)
92 {
93 	int ret;
94 
95 	if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0) {
96 		*val = 0xffffffff;
97 		return PCIBIOS_DEVICE_NOT_FOUND;
98 	}
99 
100 	/*
101 	 * We only support access to the non-extended configuration
102 	 * space when using the WA access method (or we would have to
103 	 * sacrifice 256M of CPU virtual address space.)
104 	 */
105 	if (where >= 0x100) {
106 		*val = 0xffffffff;
107 		return PCIBIOS_DEVICE_NOT_FOUND;
108 	}
109 
110 	ret = orion_pcie_rd_conf_wa((void __iomem *)ORION5X_PCIE_WA_VIRT_BASE,
111 				    bus, devfn, where, size, val);
112 
113 	return ret;
114 }
115 
116 static int pcie_wr_conf(struct pci_bus *bus, u32 devfn,
117 			int where, int size, u32 val)
118 {
119 	unsigned long flags;
120 	int ret;
121 
122 	if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0)
123 		return PCIBIOS_DEVICE_NOT_FOUND;
124 
125 	spin_lock_irqsave(&orion5x_pcie_lock, flags);
126 	ret = orion_pcie_wr_conf(PCIE_BASE, bus, devfn, where, size, val);
127 	spin_unlock_irqrestore(&orion5x_pcie_lock, flags);
128 
129 	return ret;
130 }
131 
132 static struct pci_ops pcie_ops = {
133 	.read = pcie_rd_conf,
134 	.write = pcie_wr_conf,
135 };
136 
137 
138 static int __init pcie_setup(struct pci_sys_data *sys)
139 {
140 	struct resource *res;
141 	int dev;
142 
143 	/*
144 	 * Generic PCIe unit setup.
145 	 */
146 	orion_pcie_setup(PCIE_BASE, &orion5x_mbus_dram_info);
147 
148 	/*
149 	 * Check whether to apply Orion-1/Orion-NAS PCIe config
150 	 * read transaction workaround.
151 	 */
152 	dev = orion_pcie_dev_id(PCIE_BASE);
153 	if (dev == MV88F5181_DEV_ID || dev == MV88F5182_DEV_ID) {
154 		printk(KERN_NOTICE "Applying Orion-1/Orion-NAS PCIe config "
155 				   "read transaction workaround\n");
156 		orion5x_setup_pcie_wa_win(ORION5X_PCIE_WA_PHYS_BASE,
157 					  ORION5X_PCIE_WA_SIZE);
158 		pcie_ops.read = pcie_rd_conf_wa;
159 	}
160 
161 	/*
162 	 * Request resources.
163 	 */
164 	res = kzalloc(sizeof(struct resource) * 2, GFP_KERNEL);
165 	if (!res)
166 		panic("pcie_setup unable to alloc resources");
167 
168 	/*
169 	 * IORESOURCE_IO
170 	 */
171 	res[0].name = "PCIe I/O Space";
172 	res[0].flags = IORESOURCE_IO;
173 	res[0].start = ORION5X_PCIE_IO_BUS_BASE;
174 	res[0].end = res[0].start + ORION5X_PCIE_IO_SIZE - 1;
175 	if (request_resource(&ioport_resource, &res[0]))
176 		panic("Request PCIe IO resource failed\n");
177 	sys->resource[0] = &res[0];
178 
179 	/*
180 	 * IORESOURCE_MEM
181 	 */
182 	res[1].name = "PCIe Memory Space";
183 	res[1].flags = IORESOURCE_MEM;
184 	res[1].start = ORION5X_PCIE_MEM_PHYS_BASE;
185 	res[1].end = res[1].start + ORION5X_PCIE_MEM_SIZE - 1;
186 	if (request_resource(&iomem_resource, &res[1]))
187 		panic("Request PCIe Memory resource failed\n");
188 	sys->resource[1] = &res[1];
189 
190 	sys->resource[2] = NULL;
191 	sys->io_offset = 0;
192 
193 	return 1;
194 }
195 
196 /*****************************************************************************
197  * PCI controller
198  ****************************************************************************/
199 #define PCI_MODE		ORION5X_PCI_REG(0xd00)
200 #define PCI_CMD			ORION5X_PCI_REG(0xc00)
201 #define PCI_P2P_CONF		ORION5X_PCI_REG(0x1d14)
202 #define PCI_CONF_ADDR		ORION5X_PCI_REG(0xc78)
203 #define PCI_CONF_DATA		ORION5X_PCI_REG(0xc7c)
204 
205 /*
206  * PCI_MODE bits
207  */
208 #define PCI_MODE_64BIT			(1 << 2)
209 #define PCI_MODE_PCIX			((1 << 4) | (1 << 5))
210 
211 /*
212  * PCI_CMD bits
213  */
214 #define PCI_CMD_HOST_REORDER		(1 << 29)
215 
216 /*
217  * PCI_P2P_CONF bits
218  */
219 #define PCI_P2P_BUS_OFFS		16
220 #define PCI_P2P_BUS_MASK		(0xff << PCI_P2P_BUS_OFFS)
221 #define PCI_P2P_DEV_OFFS		24
222 #define PCI_P2P_DEV_MASK		(0x1f << PCI_P2P_DEV_OFFS)
223 
224 /*
225  * PCI_CONF_ADDR bits
226  */
227 #define PCI_CONF_REG(reg)		((reg) & 0xfc)
228 #define PCI_CONF_FUNC(func)		(((func) & 0x3) << 8)
229 #define PCI_CONF_DEV(dev)		(((dev) & 0x1f) << 11)
230 #define PCI_CONF_BUS(bus)		(((bus) & 0xff) << 16)
231 #define PCI_CONF_ADDR_EN		(1 << 31)
232 
233 /*
234  * Internal configuration space
235  */
236 #define PCI_CONF_FUNC_STAT_CMD		0
237 #define PCI_CONF_REG_STAT_CMD		4
238 #define PCIX_STAT			0x64
239 #define PCIX_STAT_BUS_OFFS		8
240 #define PCIX_STAT_BUS_MASK		(0xff << PCIX_STAT_BUS_OFFS)
241 
242 /*
243  * PCI Address Decode Windows registers
244  */
245 #define PCI_BAR_SIZE_DDR_CS(n)	(((n) == 0) ? ORION5X_PCI_REG(0xc08) : \
246 				 ((n) == 1) ? ORION5X_PCI_REG(0xd08) : \
247 				 ((n) == 2) ? ORION5X_PCI_REG(0xc0c) : \
248 				 ((n) == 3) ? ORION5X_PCI_REG(0xd0c) : 0)
249 #define PCI_BAR_REMAP_DDR_CS(n)	(((n) == 0) ? ORION5X_PCI_REG(0xc48) : \
250 				 ((n) == 1) ? ORION5X_PCI_REG(0xd48) : \
251 				 ((n) == 2) ? ORION5X_PCI_REG(0xc4c) : \
252 				 ((n) == 3) ? ORION5X_PCI_REG(0xd4c) : 0)
253 #define PCI_BAR_ENABLE		ORION5X_PCI_REG(0xc3c)
254 #define PCI_ADDR_DECODE_CTRL	ORION5X_PCI_REG(0xd3c)
255 
256 /*
257  * PCI configuration helpers for BAR settings
258  */
259 #define PCI_CONF_FUNC_BAR_CS(n)		((n) >> 1)
260 #define PCI_CONF_REG_BAR_LO_CS(n)	(((n) & 1) ? 0x18 : 0x10)
261 #define PCI_CONF_REG_BAR_HI_CS(n)	(((n) & 1) ? 0x1c : 0x14)
262 
263 /*
264  * PCI config cycles are done by programming the PCI_CONF_ADDR register
265  * and then reading the PCI_CONF_DATA register. Need to make sure these
266  * transactions are atomic.
267  */
268 static DEFINE_SPINLOCK(orion5x_pci_lock);
269 
270 static int orion5x_pci_cardbus_mode;
271 
272 static int orion5x_pci_local_bus_nr(void)
273 {
274 	u32 conf = readl(PCI_P2P_CONF);
275 	return((conf & PCI_P2P_BUS_MASK) >> PCI_P2P_BUS_OFFS);
276 }
277 
278 static int orion5x_pci_hw_rd_conf(int bus, int dev, u32 func,
279 					u32 where, u32 size, u32 *val)
280 {
281 	unsigned long flags;
282 	spin_lock_irqsave(&orion5x_pci_lock, flags);
283 
284 	writel(PCI_CONF_BUS(bus) |
285 		PCI_CONF_DEV(dev) | PCI_CONF_REG(where) |
286 		PCI_CONF_FUNC(func) | PCI_CONF_ADDR_EN, PCI_CONF_ADDR);
287 
288 	*val = readl(PCI_CONF_DATA);
289 
290 	if (size == 1)
291 		*val = (*val >> (8*(where & 0x3))) & 0xff;
292 	else if (size == 2)
293 		*val = (*val >> (8*(where & 0x3))) & 0xffff;
294 
295 	spin_unlock_irqrestore(&orion5x_pci_lock, flags);
296 
297 	return PCIBIOS_SUCCESSFUL;
298 }
299 
300 static int orion5x_pci_hw_wr_conf(int bus, int dev, u32 func,
301 					u32 where, u32 size, u32 val)
302 {
303 	unsigned long flags;
304 	int ret = PCIBIOS_SUCCESSFUL;
305 
306 	spin_lock_irqsave(&orion5x_pci_lock, flags);
307 
308 	writel(PCI_CONF_BUS(bus) |
309 		PCI_CONF_DEV(dev) | PCI_CONF_REG(where) |
310 		PCI_CONF_FUNC(func) | PCI_CONF_ADDR_EN, PCI_CONF_ADDR);
311 
312 	if (size == 4) {
313 		__raw_writel(val, PCI_CONF_DATA);
314 	} else if (size == 2) {
315 		__raw_writew(val, PCI_CONF_DATA + (where & 0x3));
316 	} else if (size == 1) {
317 		__raw_writeb(val, PCI_CONF_DATA + (where & 0x3));
318 	} else {
319 		ret = PCIBIOS_BAD_REGISTER_NUMBER;
320 	}
321 
322 	spin_unlock_irqrestore(&orion5x_pci_lock, flags);
323 
324 	return ret;
325 }
326 
327 static int orion5x_pci_valid_config(int bus, u32 devfn)
328 {
329 	if (bus == orion5x_pci_local_bus_nr()) {
330 		/*
331 		 * Don't go out for local device
332 		 */
333 		if (PCI_SLOT(devfn) == 0 && PCI_FUNC(devfn) != 0)
334 			return 0;
335 
336 		/*
337 		 * When the PCI signals are directly connected to a
338 		 * Cardbus slot, ignore all but device IDs 0 and 1.
339 		 */
340 		if (orion5x_pci_cardbus_mode && PCI_SLOT(devfn) > 1)
341 			return 0;
342 	}
343 
344 	return 1;
345 }
346 
347 static int orion5x_pci_rd_conf(struct pci_bus *bus, u32 devfn,
348 				int where, int size, u32 *val)
349 {
350 	if (!orion5x_pci_valid_config(bus->number, devfn)) {
351 		*val = 0xffffffff;
352 		return PCIBIOS_DEVICE_NOT_FOUND;
353 	}
354 
355 	return orion5x_pci_hw_rd_conf(bus->number, PCI_SLOT(devfn),
356 					PCI_FUNC(devfn), where, size, val);
357 }
358 
359 static int orion5x_pci_wr_conf(struct pci_bus *bus, u32 devfn,
360 				int where, int size, u32 val)
361 {
362 	if (!orion5x_pci_valid_config(bus->number, devfn))
363 		return PCIBIOS_DEVICE_NOT_FOUND;
364 
365 	return orion5x_pci_hw_wr_conf(bus->number, PCI_SLOT(devfn),
366 					PCI_FUNC(devfn), where, size, val);
367 }
368 
369 static struct pci_ops pci_ops = {
370 	.read = orion5x_pci_rd_conf,
371 	.write = orion5x_pci_wr_conf,
372 };
373 
374 static void __init orion5x_pci_set_bus_nr(int nr)
375 {
376 	u32 p2p = readl(PCI_P2P_CONF);
377 
378 	if (readl(PCI_MODE) & PCI_MODE_PCIX) {
379 		/*
380 		 * PCI-X mode
381 		 */
382 		u32 pcix_status, bus, dev;
383 		bus = (p2p & PCI_P2P_BUS_MASK) >> PCI_P2P_BUS_OFFS;
384 		dev = (p2p & PCI_P2P_DEV_MASK) >> PCI_P2P_DEV_OFFS;
385 		orion5x_pci_hw_rd_conf(bus, dev, 0, PCIX_STAT, 4, &pcix_status);
386 		pcix_status &= ~PCIX_STAT_BUS_MASK;
387 		pcix_status |= (nr << PCIX_STAT_BUS_OFFS);
388 		orion5x_pci_hw_wr_conf(bus, dev, 0, PCIX_STAT, 4, pcix_status);
389 	} else {
390 		/*
391 		 * PCI Conventional mode
392 		 */
393 		p2p &= ~PCI_P2P_BUS_MASK;
394 		p2p |= (nr << PCI_P2P_BUS_OFFS);
395 		writel(p2p, PCI_P2P_CONF);
396 	}
397 }
398 
399 static void __init orion5x_pci_master_slave_enable(void)
400 {
401 	int bus_nr, func, reg;
402 	u32 val;
403 
404 	bus_nr = orion5x_pci_local_bus_nr();
405 	func = PCI_CONF_FUNC_STAT_CMD;
406 	reg = PCI_CONF_REG_STAT_CMD;
407 	orion5x_pci_hw_rd_conf(bus_nr, 0, func, reg, 4, &val);
408 	val |= (PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
409 	orion5x_pci_hw_wr_conf(bus_nr, 0, func, reg, 4, val | 0x7);
410 }
411 
412 static void __init orion5x_setup_pci_wins(struct mbus_dram_target_info *dram)
413 {
414 	u32 win_enable;
415 	int bus;
416 	int i;
417 
418 	/*
419 	 * First, disable windows.
420 	 */
421 	win_enable = 0xffffffff;
422 	writel(win_enable, PCI_BAR_ENABLE);
423 
424 	/*
425 	 * Setup windows for DDR banks.
426 	 */
427 	bus = orion5x_pci_local_bus_nr();
428 
429 	for (i = 0; i < dram->num_cs; i++) {
430 		struct mbus_dram_window *cs = dram->cs + i;
431 		u32 func = PCI_CONF_FUNC_BAR_CS(cs->cs_index);
432 		u32 reg;
433 		u32 val;
434 
435 		/*
436 		 * Write DRAM bank base address register.
437 		 */
438 		reg = PCI_CONF_REG_BAR_LO_CS(cs->cs_index);
439 		orion5x_pci_hw_rd_conf(bus, 0, func, reg, 4, &val);
440 		val = (cs->base & 0xfffff000) | (val & 0xfff);
441 		orion5x_pci_hw_wr_conf(bus, 0, func, reg, 4, val);
442 
443 		/*
444 		 * Write DRAM bank size register.
445 		 */
446 		reg = PCI_CONF_REG_BAR_HI_CS(cs->cs_index);
447 		orion5x_pci_hw_wr_conf(bus, 0, func, reg, 4, 0);
448 		writel((cs->size - 1) & 0xfffff000,
449 			PCI_BAR_SIZE_DDR_CS(cs->cs_index));
450 		writel(cs->base & 0xfffff000,
451 			PCI_BAR_REMAP_DDR_CS(cs->cs_index));
452 
453 		/*
454 		 * Enable decode window for this chip select.
455 		 */
456 		win_enable &= ~(1 << cs->cs_index);
457 	}
458 
459 	/*
460 	 * Re-enable decode windows.
461 	 */
462 	writel(win_enable, PCI_BAR_ENABLE);
463 
464 	/*
465 	 * Disable automatic update of address remaping when writing to BARs.
466 	 */
467 	orion5x_setbits(PCI_ADDR_DECODE_CTRL, 1);
468 }
469 
470 static int __init pci_setup(struct pci_sys_data *sys)
471 {
472 	struct resource *res;
473 
474 	/*
475 	 * Point PCI unit MBUS decode windows to DRAM space.
476 	 */
477 	orion5x_setup_pci_wins(&orion5x_mbus_dram_info);
478 
479 	/*
480 	 * Master + Slave enable
481 	 */
482 	orion5x_pci_master_slave_enable();
483 
484 	/*
485 	 * Force ordering
486 	 */
487 	orion5x_setbits(PCI_CMD, PCI_CMD_HOST_REORDER);
488 
489 	/*
490 	 * Request resources
491 	 */
492 	res = kzalloc(sizeof(struct resource) * 2, GFP_KERNEL);
493 	if (!res)
494 		panic("pci_setup unable to alloc resources");
495 
496 	/*
497 	 * IORESOURCE_IO
498 	 */
499 	res[0].name = "PCI I/O Space";
500 	res[0].flags = IORESOURCE_IO;
501 	res[0].start = ORION5X_PCI_IO_BUS_BASE;
502 	res[0].end = res[0].start + ORION5X_PCI_IO_SIZE - 1;
503 	if (request_resource(&ioport_resource, &res[0]))
504 		panic("Request PCI IO resource failed\n");
505 	sys->resource[0] = &res[0];
506 
507 	/*
508 	 * IORESOURCE_MEM
509 	 */
510 	res[1].name = "PCI Memory Space";
511 	res[1].flags = IORESOURCE_MEM;
512 	res[1].start = ORION5X_PCI_MEM_PHYS_BASE;
513 	res[1].end = res[1].start + ORION5X_PCI_MEM_SIZE - 1;
514 	if (request_resource(&iomem_resource, &res[1]))
515 		panic("Request PCI Memory resource failed\n");
516 	sys->resource[1] = &res[1];
517 
518 	sys->resource[2] = NULL;
519 	sys->io_offset = 0;
520 
521 	return 1;
522 }
523 
524 
525 /*****************************************************************************
526  * General PCIe + PCI
527  ****************************************************************************/
528 static void __devinit rc_pci_fixup(struct pci_dev *dev)
529 {
530 	/*
531 	 * Prevent enumeration of root complex.
532 	 */
533 	if (dev->bus->parent == NULL && dev->devfn == 0) {
534 		int i;
535 
536 		for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
537 			dev->resource[i].start = 0;
538 			dev->resource[i].end   = 0;
539 			dev->resource[i].flags = 0;
540 		}
541 	}
542 }
543 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MARVELL, PCI_ANY_ID, rc_pci_fixup);
544 
545 static int orion5x_pci_disabled __initdata;
546 
547 void __init orion5x_pci_disable(void)
548 {
549 	orion5x_pci_disabled = 1;
550 }
551 
552 void __init orion5x_pci_set_cardbus_mode(void)
553 {
554 	orion5x_pci_cardbus_mode = 1;
555 }
556 
557 int __init orion5x_pci_sys_setup(int nr, struct pci_sys_data *sys)
558 {
559 	int ret = 0;
560 
561 	if (nr == 0) {
562 		orion_pcie_set_local_bus_nr(PCIE_BASE, sys->busnr);
563 		ret = pcie_setup(sys);
564 	} else if (nr == 1 && !orion5x_pci_disabled) {
565 		orion5x_pci_set_bus_nr(sys->busnr);
566 		ret = pci_setup(sys);
567 	}
568 
569 	return ret;
570 }
571 
572 struct pci_bus __init *orion5x_pci_sys_scan_bus(int nr, struct pci_sys_data *sys)
573 {
574 	struct pci_bus *bus;
575 
576 	if (nr == 0) {
577 		bus = pci_scan_bus(sys->busnr, &pcie_ops, sys);
578 	} else if (nr == 1 && !orion5x_pci_disabled) {
579 		bus = pci_scan_bus(sys->busnr, &pci_ops, sys);
580 	} else {
581 		bus = NULL;
582 		BUG();
583 	}
584 
585 	return bus;
586 }
587 
588 int __init orion5x_pci_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
589 {
590 	int bus = dev->bus->number;
591 
592 	/*
593 	 * PCIe endpoint?
594 	 */
595 	if (orion5x_pci_disabled || bus < orion5x_pci_local_bus_nr())
596 		return IRQ_ORION5X_PCIE0_INT;
597 
598 	return -1;
599 }
600