xref: /openbmc/linux/arch/arm/mach-orion5x/pci.c (revision af901ca1)
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 ORION5X_PCI_REG(x)	(ORION5X_PCI_VIRT_BASE | (x))
200 #define PCI_MODE		ORION5X_PCI_REG(0xd00)
201 #define PCI_CMD			ORION5X_PCI_REG(0xc00)
202 #define PCI_P2P_CONF		ORION5X_PCI_REG(0x1d14)
203 #define PCI_CONF_ADDR		ORION5X_PCI_REG(0xc78)
204 #define PCI_CONF_DATA		ORION5X_PCI_REG(0xc7c)
205 
206 /*
207  * PCI_MODE bits
208  */
209 #define PCI_MODE_64BIT			(1 << 2)
210 #define PCI_MODE_PCIX			((1 << 4) | (1 << 5))
211 
212 /*
213  * PCI_CMD bits
214  */
215 #define PCI_CMD_HOST_REORDER		(1 << 29)
216 
217 /*
218  * PCI_P2P_CONF bits
219  */
220 #define PCI_P2P_BUS_OFFS		16
221 #define PCI_P2P_BUS_MASK		(0xff << PCI_P2P_BUS_OFFS)
222 #define PCI_P2P_DEV_OFFS		24
223 #define PCI_P2P_DEV_MASK		(0x1f << PCI_P2P_DEV_OFFS)
224 
225 /*
226  * PCI_CONF_ADDR bits
227  */
228 #define PCI_CONF_REG(reg)		((reg) & 0xfc)
229 #define PCI_CONF_FUNC(func)		(((func) & 0x3) << 8)
230 #define PCI_CONF_DEV(dev)		(((dev) & 0x1f) << 11)
231 #define PCI_CONF_BUS(bus)		(((bus) & 0xff) << 16)
232 #define PCI_CONF_ADDR_EN		(1 << 31)
233 
234 /*
235  * Internal configuration space
236  */
237 #define PCI_CONF_FUNC_STAT_CMD		0
238 #define PCI_CONF_REG_STAT_CMD		4
239 #define PCIX_STAT			0x64
240 #define PCIX_STAT_BUS_OFFS		8
241 #define PCIX_STAT_BUS_MASK		(0xff << PCIX_STAT_BUS_OFFS)
242 
243 /*
244  * PCI Address Decode Windows registers
245  */
246 #define PCI_BAR_SIZE_DDR_CS(n)	(((n) == 0) ? ORION5X_PCI_REG(0xc08) : \
247 				 ((n) == 1) ? ORION5X_PCI_REG(0xd08) : \
248 				 ((n) == 2) ? ORION5X_PCI_REG(0xc0c) : \
249 				 ((n) == 3) ? ORION5X_PCI_REG(0xd0c) : 0)
250 #define PCI_BAR_REMAP_DDR_CS(n)	(((n) == 0) ? ORION5X_PCI_REG(0xc48) : \
251 				 ((n) == 1) ? ORION5X_PCI_REG(0xd48) : \
252 				 ((n) == 2) ? ORION5X_PCI_REG(0xc4c) : \
253 				 ((n) == 3) ? ORION5X_PCI_REG(0xd4c) : 0)
254 #define PCI_BAR_ENABLE		ORION5X_PCI_REG(0xc3c)
255 #define PCI_ADDR_DECODE_CTRL	ORION5X_PCI_REG(0xd3c)
256 
257 /*
258  * PCI configuration helpers for BAR settings
259  */
260 #define PCI_CONF_FUNC_BAR_CS(n)		((n) >> 1)
261 #define PCI_CONF_REG_BAR_LO_CS(n)	(((n) & 1) ? 0x18 : 0x10)
262 #define PCI_CONF_REG_BAR_HI_CS(n)	(((n) & 1) ? 0x1c : 0x14)
263 
264 /*
265  * PCI config cycles are done by programming the PCI_CONF_ADDR register
266  * and then reading the PCI_CONF_DATA register. Need to make sure these
267  * transactions are atomic.
268  */
269 static DEFINE_SPINLOCK(orion5x_pci_lock);
270 
271 static int orion5x_pci_cardbus_mode;
272 
273 static int orion5x_pci_local_bus_nr(void)
274 {
275 	u32 conf = readl(PCI_P2P_CONF);
276 	return((conf & PCI_P2P_BUS_MASK) >> PCI_P2P_BUS_OFFS);
277 }
278 
279 static int orion5x_pci_hw_rd_conf(int bus, int dev, u32 func,
280 					u32 where, u32 size, u32 *val)
281 {
282 	unsigned long flags;
283 	spin_lock_irqsave(&orion5x_pci_lock, flags);
284 
285 	writel(PCI_CONF_BUS(bus) |
286 		PCI_CONF_DEV(dev) | PCI_CONF_REG(where) |
287 		PCI_CONF_FUNC(func) | PCI_CONF_ADDR_EN, PCI_CONF_ADDR);
288 
289 	*val = readl(PCI_CONF_DATA);
290 
291 	if (size == 1)
292 		*val = (*val >> (8*(where & 0x3))) & 0xff;
293 	else if (size == 2)
294 		*val = (*val >> (8*(where & 0x3))) & 0xffff;
295 
296 	spin_unlock_irqrestore(&orion5x_pci_lock, flags);
297 
298 	return PCIBIOS_SUCCESSFUL;
299 }
300 
301 static int orion5x_pci_hw_wr_conf(int bus, int dev, u32 func,
302 					u32 where, u32 size, u32 val)
303 {
304 	unsigned long flags;
305 	int ret = PCIBIOS_SUCCESSFUL;
306 
307 	spin_lock_irqsave(&orion5x_pci_lock, flags);
308 
309 	writel(PCI_CONF_BUS(bus) |
310 		PCI_CONF_DEV(dev) | PCI_CONF_REG(where) |
311 		PCI_CONF_FUNC(func) | PCI_CONF_ADDR_EN, PCI_CONF_ADDR);
312 
313 	if (size == 4) {
314 		__raw_writel(val, PCI_CONF_DATA);
315 	} else if (size == 2) {
316 		__raw_writew(val, PCI_CONF_DATA + (where & 0x3));
317 	} else if (size == 1) {
318 		__raw_writeb(val, PCI_CONF_DATA + (where & 0x3));
319 	} else {
320 		ret = PCIBIOS_BAD_REGISTER_NUMBER;
321 	}
322 
323 	spin_unlock_irqrestore(&orion5x_pci_lock, flags);
324 
325 	return ret;
326 }
327 
328 static int orion5x_pci_valid_config(int bus, u32 devfn)
329 {
330 	if (bus == orion5x_pci_local_bus_nr()) {
331 		/*
332 		 * Don't go out for local device
333 		 */
334 		if (PCI_SLOT(devfn) == 0 && PCI_FUNC(devfn) != 0)
335 			return 0;
336 
337 		/*
338 		 * When the PCI signals are directly connected to a
339 		 * Cardbus slot, ignore all but device IDs 0 and 1.
340 		 */
341 		if (orion5x_pci_cardbus_mode && PCI_SLOT(devfn) > 1)
342 			return 0;
343 	}
344 
345 	return 1;
346 }
347 
348 static int orion5x_pci_rd_conf(struct pci_bus *bus, u32 devfn,
349 				int where, int size, u32 *val)
350 {
351 	if (!orion5x_pci_valid_config(bus->number, devfn)) {
352 		*val = 0xffffffff;
353 		return PCIBIOS_DEVICE_NOT_FOUND;
354 	}
355 
356 	return orion5x_pci_hw_rd_conf(bus->number, PCI_SLOT(devfn),
357 					PCI_FUNC(devfn), where, size, val);
358 }
359 
360 static int orion5x_pci_wr_conf(struct pci_bus *bus, u32 devfn,
361 				int where, int size, u32 val)
362 {
363 	if (!orion5x_pci_valid_config(bus->number, devfn))
364 		return PCIBIOS_DEVICE_NOT_FOUND;
365 
366 	return orion5x_pci_hw_wr_conf(bus->number, PCI_SLOT(devfn),
367 					PCI_FUNC(devfn), where, size, val);
368 }
369 
370 static struct pci_ops pci_ops = {
371 	.read = orion5x_pci_rd_conf,
372 	.write = orion5x_pci_wr_conf,
373 };
374 
375 static void __init orion5x_pci_set_bus_nr(int nr)
376 {
377 	u32 p2p = readl(PCI_P2P_CONF);
378 
379 	if (readl(PCI_MODE) & PCI_MODE_PCIX) {
380 		/*
381 		 * PCI-X mode
382 		 */
383 		u32 pcix_status, bus, dev;
384 		bus = (p2p & PCI_P2P_BUS_MASK) >> PCI_P2P_BUS_OFFS;
385 		dev = (p2p & PCI_P2P_DEV_MASK) >> PCI_P2P_DEV_OFFS;
386 		orion5x_pci_hw_rd_conf(bus, dev, 0, PCIX_STAT, 4, &pcix_status);
387 		pcix_status &= ~PCIX_STAT_BUS_MASK;
388 		pcix_status |= (nr << PCIX_STAT_BUS_OFFS);
389 		orion5x_pci_hw_wr_conf(bus, dev, 0, PCIX_STAT, 4, pcix_status);
390 	} else {
391 		/*
392 		 * PCI Conventional mode
393 		 */
394 		p2p &= ~PCI_P2P_BUS_MASK;
395 		p2p |= (nr << PCI_P2P_BUS_OFFS);
396 		writel(p2p, PCI_P2P_CONF);
397 	}
398 }
399 
400 static void __init orion5x_pci_master_slave_enable(void)
401 {
402 	int bus_nr, func, reg;
403 	u32 val;
404 
405 	bus_nr = orion5x_pci_local_bus_nr();
406 	func = PCI_CONF_FUNC_STAT_CMD;
407 	reg = PCI_CONF_REG_STAT_CMD;
408 	orion5x_pci_hw_rd_conf(bus_nr, 0, func, reg, 4, &val);
409 	val |= (PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
410 	orion5x_pci_hw_wr_conf(bus_nr, 0, func, reg, 4, val | 0x7);
411 }
412 
413 static void __init orion5x_setup_pci_wins(struct mbus_dram_target_info *dram)
414 {
415 	u32 win_enable;
416 	int bus;
417 	int i;
418 
419 	/*
420 	 * First, disable windows.
421 	 */
422 	win_enable = 0xffffffff;
423 	writel(win_enable, PCI_BAR_ENABLE);
424 
425 	/*
426 	 * Setup windows for DDR banks.
427 	 */
428 	bus = orion5x_pci_local_bus_nr();
429 
430 	for (i = 0; i < dram->num_cs; i++) {
431 		struct mbus_dram_window *cs = dram->cs + i;
432 		u32 func = PCI_CONF_FUNC_BAR_CS(cs->cs_index);
433 		u32 reg;
434 		u32 val;
435 
436 		/*
437 		 * Write DRAM bank base address register.
438 		 */
439 		reg = PCI_CONF_REG_BAR_LO_CS(cs->cs_index);
440 		orion5x_pci_hw_rd_conf(bus, 0, func, reg, 4, &val);
441 		val = (cs->base & 0xfffff000) | (val & 0xfff);
442 		orion5x_pci_hw_wr_conf(bus, 0, func, reg, 4, val);
443 
444 		/*
445 		 * Write DRAM bank size register.
446 		 */
447 		reg = PCI_CONF_REG_BAR_HI_CS(cs->cs_index);
448 		orion5x_pci_hw_wr_conf(bus, 0, func, reg, 4, 0);
449 		writel((cs->size - 1) & 0xfffff000,
450 			PCI_BAR_SIZE_DDR_CS(cs->cs_index));
451 		writel(cs->base & 0xfffff000,
452 			PCI_BAR_REMAP_DDR_CS(cs->cs_index));
453 
454 		/*
455 		 * Enable decode window for this chip select.
456 		 */
457 		win_enable &= ~(1 << cs->cs_index);
458 	}
459 
460 	/*
461 	 * Re-enable decode windows.
462 	 */
463 	writel(win_enable, PCI_BAR_ENABLE);
464 
465 	/*
466 	 * Disable automatic update of address remapping when writing to BARs.
467 	 */
468 	orion5x_setbits(PCI_ADDR_DECODE_CTRL, 1);
469 }
470 
471 static int __init pci_setup(struct pci_sys_data *sys)
472 {
473 	struct resource *res;
474 
475 	/*
476 	 * Point PCI unit MBUS decode windows to DRAM space.
477 	 */
478 	orion5x_setup_pci_wins(&orion5x_mbus_dram_info);
479 
480 	/*
481 	 * Master + Slave enable
482 	 */
483 	orion5x_pci_master_slave_enable();
484 
485 	/*
486 	 * Force ordering
487 	 */
488 	orion5x_setbits(PCI_CMD, PCI_CMD_HOST_REORDER);
489 
490 	/*
491 	 * Request resources
492 	 */
493 	res = kzalloc(sizeof(struct resource) * 2, GFP_KERNEL);
494 	if (!res)
495 		panic("pci_setup unable to alloc resources");
496 
497 	/*
498 	 * IORESOURCE_IO
499 	 */
500 	res[0].name = "PCI I/O Space";
501 	res[0].flags = IORESOURCE_IO;
502 	res[0].start = ORION5X_PCI_IO_BUS_BASE;
503 	res[0].end = res[0].start + ORION5X_PCI_IO_SIZE - 1;
504 	if (request_resource(&ioport_resource, &res[0]))
505 		panic("Request PCI IO resource failed\n");
506 	sys->resource[0] = &res[0];
507 
508 	/*
509 	 * IORESOURCE_MEM
510 	 */
511 	res[1].name = "PCI Memory Space";
512 	res[1].flags = IORESOURCE_MEM;
513 	res[1].start = ORION5X_PCI_MEM_PHYS_BASE;
514 	res[1].end = res[1].start + ORION5X_PCI_MEM_SIZE - 1;
515 	if (request_resource(&iomem_resource, &res[1]))
516 		panic("Request PCI Memory resource failed\n");
517 	sys->resource[1] = &res[1];
518 
519 	sys->resource[2] = NULL;
520 	sys->io_offset = 0;
521 
522 	return 1;
523 }
524 
525 
526 /*****************************************************************************
527  * General PCIe + PCI
528  ****************************************************************************/
529 static void __devinit rc_pci_fixup(struct pci_dev *dev)
530 {
531 	/*
532 	 * Prevent enumeration of root complex.
533 	 */
534 	if (dev->bus->parent == NULL && dev->devfn == 0) {
535 		int i;
536 
537 		for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
538 			dev->resource[i].start = 0;
539 			dev->resource[i].end   = 0;
540 			dev->resource[i].flags = 0;
541 		}
542 	}
543 }
544 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MARVELL, PCI_ANY_ID, rc_pci_fixup);
545 
546 static int orion5x_pci_disabled __initdata;
547 
548 void __init orion5x_pci_disable(void)
549 {
550 	orion5x_pci_disabled = 1;
551 }
552 
553 void __init orion5x_pci_set_cardbus_mode(void)
554 {
555 	orion5x_pci_cardbus_mode = 1;
556 }
557 
558 int __init orion5x_pci_sys_setup(int nr, struct pci_sys_data *sys)
559 {
560 	int ret = 0;
561 
562 	if (nr == 0) {
563 		orion_pcie_set_local_bus_nr(PCIE_BASE, sys->busnr);
564 		ret = pcie_setup(sys);
565 	} else if (nr == 1 && !orion5x_pci_disabled) {
566 		orion5x_pci_set_bus_nr(sys->busnr);
567 		ret = pci_setup(sys);
568 	}
569 
570 	return ret;
571 }
572 
573 struct pci_bus __init *orion5x_pci_sys_scan_bus(int nr, struct pci_sys_data *sys)
574 {
575 	struct pci_bus *bus;
576 
577 	if (nr == 0) {
578 		bus = pci_scan_bus(sys->busnr, &pcie_ops, sys);
579 	} else if (nr == 1 && !orion5x_pci_disabled) {
580 		bus = pci_scan_bus(sys->busnr, &pci_ops, sys);
581 	} else {
582 		bus = NULL;
583 		BUG();
584 	}
585 
586 	return bus;
587 }
588 
589 int __init orion5x_pci_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
590 {
591 	int bus = dev->bus->number;
592 
593 	/*
594 	 * PCIe endpoint?
595 	 */
596 	if (orion5x_pci_disabled || bus < orion5x_pci_local_bus_nr())
597 		return IRQ_ORION5X_PCIE0_INT;
598 
599 	return -1;
600 }
601