xref: /openbmc/linux/arch/arm/mach-orion5x/pci.c (revision cc22b4c1)
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/slab.h>
16 #include <linux/mbus.h>
17 #include <asm/irq.h>
18 #include <asm/mach/pci.h>
19 #include <plat/pcie.h>
20 #include "common.h"
21 
22 /*****************************************************************************
23  * Orion has one PCIe controller and one PCI controller.
24  *
25  * Note1: The local PCIe bus number is '0'. The local PCI bus number
26  * follows the scanned PCIe bridged busses, if any.
27  *
28  * Note2: It is possible for PCI/PCIe agents to access many subsystem's
29  * space, by configuring BARs and Address Decode Windows, e.g. flashes on
30  * device bus, Orion registers, etc. However this code only enable the
31  * access to DDR banks.
32  ****************************************************************************/
33 
34 
35 /*****************************************************************************
36  * PCIe controller
37  ****************************************************************************/
38 #define PCIE_BASE	((void __iomem *)ORION5X_PCIE_VIRT_BASE)
39 
40 void __init orion5x_pcie_id(u32 *dev, u32 *rev)
41 {
42 	*dev = orion_pcie_dev_id(PCIE_BASE);
43 	*rev = orion_pcie_rev(PCIE_BASE);
44 }
45 
46 static int pcie_valid_config(int bus, int dev)
47 {
48 	/*
49 	 * Don't go out when trying to access --
50 	 * 1. nonexisting device on local bus
51 	 * 2. where there's no device connected (no link)
52 	 */
53 	if (bus == 0 && dev == 0)
54 		return 1;
55 
56 	if (!orion_pcie_link_up(PCIE_BASE))
57 		return 0;
58 
59 	if (bus == 0 && dev != 1)
60 		return 0;
61 
62 	return 1;
63 }
64 
65 
66 /*
67  * PCIe config cycles are done by programming the PCIE_CONF_ADDR register
68  * and then reading the PCIE_CONF_DATA register. Need to make sure these
69  * transactions are atomic.
70  */
71 static DEFINE_SPINLOCK(orion5x_pcie_lock);
72 
73 static int pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
74 			int size, u32 *val)
75 {
76 	unsigned long flags;
77 	int ret;
78 
79 	if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0) {
80 		*val = 0xffffffff;
81 		return PCIBIOS_DEVICE_NOT_FOUND;
82 	}
83 
84 	spin_lock_irqsave(&orion5x_pcie_lock, flags);
85 	ret = orion_pcie_rd_conf(PCIE_BASE, bus, devfn, where, size, val);
86 	spin_unlock_irqrestore(&orion5x_pcie_lock, flags);
87 
88 	return ret;
89 }
90 
91 static int pcie_rd_conf_wa(struct pci_bus *bus, u32 devfn,
92 			   int where, int size, u32 *val)
93 {
94 	int ret;
95 
96 	if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0) {
97 		*val = 0xffffffff;
98 		return PCIBIOS_DEVICE_NOT_FOUND;
99 	}
100 
101 	/*
102 	 * We only support access to the non-extended configuration
103 	 * space when using the WA access method (or we would have to
104 	 * sacrifice 256M of CPU virtual address space.)
105 	 */
106 	if (where >= 0x100) {
107 		*val = 0xffffffff;
108 		return PCIBIOS_DEVICE_NOT_FOUND;
109 	}
110 
111 	ret = orion_pcie_rd_conf_wa((void __iomem *)ORION5X_PCIE_WA_VIRT_BASE,
112 				    bus, devfn, where, size, val);
113 
114 	return ret;
115 }
116 
117 static int pcie_wr_conf(struct pci_bus *bus, u32 devfn,
118 			int where, int size, u32 val)
119 {
120 	unsigned long flags;
121 	int ret;
122 
123 	if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0)
124 		return PCIBIOS_DEVICE_NOT_FOUND;
125 
126 	spin_lock_irqsave(&orion5x_pcie_lock, flags);
127 	ret = orion_pcie_wr_conf(PCIE_BASE, bus, devfn, where, size, val);
128 	spin_unlock_irqrestore(&orion5x_pcie_lock, flags);
129 
130 	return ret;
131 }
132 
133 static struct pci_ops pcie_ops = {
134 	.read = pcie_rd_conf,
135 	.write = pcie_wr_conf,
136 };
137 
138 
139 static int __init pcie_setup(struct pci_sys_data *sys)
140 {
141 	struct resource *res;
142 	int dev;
143 
144 	/*
145 	 * Generic PCIe unit setup.
146 	 */
147 	orion_pcie_setup(PCIE_BASE, &orion5x_mbus_dram_info);
148 
149 	/*
150 	 * Check whether to apply Orion-1/Orion-NAS PCIe config
151 	 * read transaction workaround.
152 	 */
153 	dev = orion_pcie_dev_id(PCIE_BASE);
154 	if (dev == MV88F5181_DEV_ID || dev == MV88F5182_DEV_ID) {
155 		printk(KERN_NOTICE "Applying Orion-1/Orion-NAS PCIe config "
156 				   "read transaction workaround\n");
157 		orion5x_setup_pcie_wa_win(ORION5X_PCIE_WA_PHYS_BASE,
158 					  ORION5X_PCIE_WA_SIZE);
159 		pcie_ops.read = pcie_rd_conf_wa;
160 	}
161 
162 	/*
163 	 * Request resources.
164 	 */
165 	res = kzalloc(sizeof(struct resource) * 2, GFP_KERNEL);
166 	if (!res)
167 		panic("pcie_setup unable to alloc resources");
168 
169 	/*
170 	 * IORESOURCE_IO
171 	 */
172 	res[0].name = "PCIe I/O Space";
173 	res[0].flags = IORESOURCE_IO;
174 	res[0].start = ORION5X_PCIE_IO_BUS_BASE;
175 	res[0].end = res[0].start + ORION5X_PCIE_IO_SIZE - 1;
176 	if (request_resource(&ioport_resource, &res[0]))
177 		panic("Request PCIe IO resource failed\n");
178 	sys->resource[0] = &res[0];
179 
180 	/*
181 	 * IORESOURCE_MEM
182 	 */
183 	res[1].name = "PCIe Memory Space";
184 	res[1].flags = IORESOURCE_MEM;
185 	res[1].start = ORION5X_PCIE_MEM_PHYS_BASE;
186 	res[1].end = res[1].start + ORION5X_PCIE_MEM_SIZE - 1;
187 	if (request_resource(&iomem_resource, &res[1]))
188 		panic("Request PCIe Memory resource failed\n");
189 	sys->resource[1] = &res[1];
190 
191 	sys->resource[2] = NULL;
192 	sys->io_offset = 0;
193 
194 	return 1;
195 }
196 
197 /*****************************************************************************
198  * PCI controller
199  ****************************************************************************/
200 #define ORION5X_PCI_REG(x)	(ORION5X_PCI_VIRT_BASE | (x))
201 #define PCI_MODE		ORION5X_PCI_REG(0xd00)
202 #define PCI_CMD			ORION5X_PCI_REG(0xc00)
203 #define PCI_P2P_CONF		ORION5X_PCI_REG(0x1d14)
204 #define PCI_CONF_ADDR		ORION5X_PCI_REG(0xc78)
205 #define PCI_CONF_DATA		ORION5X_PCI_REG(0xc7c)
206 
207 /*
208  * PCI_MODE bits
209  */
210 #define PCI_MODE_64BIT			(1 << 2)
211 #define PCI_MODE_PCIX			((1 << 4) | (1 << 5))
212 
213 /*
214  * PCI_CMD bits
215  */
216 #define PCI_CMD_HOST_REORDER		(1 << 29)
217 
218 /*
219  * PCI_P2P_CONF bits
220  */
221 #define PCI_P2P_BUS_OFFS		16
222 #define PCI_P2P_BUS_MASK		(0xff << PCI_P2P_BUS_OFFS)
223 #define PCI_P2P_DEV_OFFS		24
224 #define PCI_P2P_DEV_MASK		(0x1f << PCI_P2P_DEV_OFFS)
225 
226 /*
227  * PCI_CONF_ADDR bits
228  */
229 #define PCI_CONF_REG(reg)		((reg) & 0xfc)
230 #define PCI_CONF_FUNC(func)		(((func) & 0x3) << 8)
231 #define PCI_CONF_DEV(dev)		(((dev) & 0x1f) << 11)
232 #define PCI_CONF_BUS(bus)		(((bus) & 0xff) << 16)
233 #define PCI_CONF_ADDR_EN		(1 << 31)
234 
235 /*
236  * Internal configuration space
237  */
238 #define PCI_CONF_FUNC_STAT_CMD		0
239 #define PCI_CONF_REG_STAT_CMD		4
240 #define PCIX_STAT			0x64
241 #define PCIX_STAT_BUS_OFFS		8
242 #define PCIX_STAT_BUS_MASK		(0xff << PCIX_STAT_BUS_OFFS)
243 
244 /*
245  * PCI Address Decode Windows registers
246  */
247 #define PCI_BAR_SIZE_DDR_CS(n)	(((n) == 0) ? ORION5X_PCI_REG(0xc08) : \
248 				 ((n) == 1) ? ORION5X_PCI_REG(0xd08) : \
249 				 ((n) == 2) ? ORION5X_PCI_REG(0xc0c) : \
250 				 ((n) == 3) ? ORION5X_PCI_REG(0xd0c) : 0)
251 #define PCI_BAR_REMAP_DDR_CS(n)	(((n) == 0) ? ORION5X_PCI_REG(0xc48) : \
252 				 ((n) == 1) ? ORION5X_PCI_REG(0xd48) : \
253 				 ((n) == 2) ? ORION5X_PCI_REG(0xc4c) : \
254 				 ((n) == 3) ? ORION5X_PCI_REG(0xd4c) : 0)
255 #define PCI_BAR_ENABLE		ORION5X_PCI_REG(0xc3c)
256 #define PCI_ADDR_DECODE_CTRL	ORION5X_PCI_REG(0xd3c)
257 
258 /*
259  * PCI configuration helpers for BAR settings
260  */
261 #define PCI_CONF_FUNC_BAR_CS(n)		((n) >> 1)
262 #define PCI_CONF_REG_BAR_LO_CS(n)	(((n) & 1) ? 0x18 : 0x10)
263 #define PCI_CONF_REG_BAR_HI_CS(n)	(((n) & 1) ? 0x1c : 0x14)
264 
265 /*
266  * PCI config cycles are done by programming the PCI_CONF_ADDR register
267  * and then reading the PCI_CONF_DATA register. Need to make sure these
268  * transactions are atomic.
269  */
270 static DEFINE_SPINLOCK(orion5x_pci_lock);
271 
272 static int orion5x_pci_cardbus_mode;
273 
274 static int orion5x_pci_local_bus_nr(void)
275 {
276 	u32 conf = readl(PCI_P2P_CONF);
277 	return((conf & PCI_P2P_BUS_MASK) >> PCI_P2P_BUS_OFFS);
278 }
279 
280 static int orion5x_pci_hw_rd_conf(int bus, int dev, u32 func,
281 					u32 where, u32 size, u32 *val)
282 {
283 	unsigned long flags;
284 	spin_lock_irqsave(&orion5x_pci_lock, flags);
285 
286 	writel(PCI_CONF_BUS(bus) |
287 		PCI_CONF_DEV(dev) | PCI_CONF_REG(where) |
288 		PCI_CONF_FUNC(func) | PCI_CONF_ADDR_EN, PCI_CONF_ADDR);
289 
290 	*val = readl(PCI_CONF_DATA);
291 
292 	if (size == 1)
293 		*val = (*val >> (8*(where & 0x3))) & 0xff;
294 	else if (size == 2)
295 		*val = (*val >> (8*(where & 0x3))) & 0xffff;
296 
297 	spin_unlock_irqrestore(&orion5x_pci_lock, flags);
298 
299 	return PCIBIOS_SUCCESSFUL;
300 }
301 
302 static int orion5x_pci_hw_wr_conf(int bus, int dev, u32 func,
303 					u32 where, u32 size, u32 val)
304 {
305 	unsigned long flags;
306 	int ret = PCIBIOS_SUCCESSFUL;
307 
308 	spin_lock_irqsave(&orion5x_pci_lock, flags);
309 
310 	writel(PCI_CONF_BUS(bus) |
311 		PCI_CONF_DEV(dev) | PCI_CONF_REG(where) |
312 		PCI_CONF_FUNC(func) | PCI_CONF_ADDR_EN, PCI_CONF_ADDR);
313 
314 	if (size == 4) {
315 		__raw_writel(val, PCI_CONF_DATA);
316 	} else if (size == 2) {
317 		__raw_writew(val, PCI_CONF_DATA + (where & 0x3));
318 	} else if (size == 1) {
319 		__raw_writeb(val, PCI_CONF_DATA + (where & 0x3));
320 	} else {
321 		ret = PCIBIOS_BAD_REGISTER_NUMBER;
322 	}
323 
324 	spin_unlock_irqrestore(&orion5x_pci_lock, flags);
325 
326 	return ret;
327 }
328 
329 static int orion5x_pci_valid_config(int bus, u32 devfn)
330 {
331 	if (bus == orion5x_pci_local_bus_nr()) {
332 		/*
333 		 * Don't go out for local device
334 		 */
335 		if (PCI_SLOT(devfn) == 0 && PCI_FUNC(devfn) != 0)
336 			return 0;
337 
338 		/*
339 		 * When the PCI signals are directly connected to a
340 		 * Cardbus slot, ignore all but device IDs 0 and 1.
341 		 */
342 		if (orion5x_pci_cardbus_mode && PCI_SLOT(devfn) > 1)
343 			return 0;
344 	}
345 
346 	return 1;
347 }
348 
349 static int orion5x_pci_rd_conf(struct pci_bus *bus, u32 devfn,
350 				int where, int size, u32 *val)
351 {
352 	if (!orion5x_pci_valid_config(bus->number, devfn)) {
353 		*val = 0xffffffff;
354 		return PCIBIOS_DEVICE_NOT_FOUND;
355 	}
356 
357 	return orion5x_pci_hw_rd_conf(bus->number, PCI_SLOT(devfn),
358 					PCI_FUNC(devfn), where, size, val);
359 }
360 
361 static int orion5x_pci_wr_conf(struct pci_bus *bus, u32 devfn,
362 				int where, int size, u32 val)
363 {
364 	if (!orion5x_pci_valid_config(bus->number, devfn))
365 		return PCIBIOS_DEVICE_NOT_FOUND;
366 
367 	return orion5x_pci_hw_wr_conf(bus->number, PCI_SLOT(devfn),
368 					PCI_FUNC(devfn), where, size, val);
369 }
370 
371 static struct pci_ops pci_ops = {
372 	.read = orion5x_pci_rd_conf,
373 	.write = orion5x_pci_wr_conf,
374 };
375 
376 static void __init orion5x_pci_set_bus_nr(int nr)
377 {
378 	u32 p2p = readl(PCI_P2P_CONF);
379 
380 	if (readl(PCI_MODE) & PCI_MODE_PCIX) {
381 		/*
382 		 * PCI-X mode
383 		 */
384 		u32 pcix_status, bus, dev;
385 		bus = (p2p & PCI_P2P_BUS_MASK) >> PCI_P2P_BUS_OFFS;
386 		dev = (p2p & PCI_P2P_DEV_MASK) >> PCI_P2P_DEV_OFFS;
387 		orion5x_pci_hw_rd_conf(bus, dev, 0, PCIX_STAT, 4, &pcix_status);
388 		pcix_status &= ~PCIX_STAT_BUS_MASK;
389 		pcix_status |= (nr << PCIX_STAT_BUS_OFFS);
390 		orion5x_pci_hw_wr_conf(bus, dev, 0, PCIX_STAT, 4, pcix_status);
391 	} else {
392 		/*
393 		 * PCI Conventional mode
394 		 */
395 		p2p &= ~PCI_P2P_BUS_MASK;
396 		p2p |= (nr << PCI_P2P_BUS_OFFS);
397 		writel(p2p, PCI_P2P_CONF);
398 	}
399 }
400 
401 static void __init orion5x_pci_master_slave_enable(void)
402 {
403 	int bus_nr, func, reg;
404 	u32 val;
405 
406 	bus_nr = orion5x_pci_local_bus_nr();
407 	func = PCI_CONF_FUNC_STAT_CMD;
408 	reg = PCI_CONF_REG_STAT_CMD;
409 	orion5x_pci_hw_rd_conf(bus_nr, 0, func, reg, 4, &val);
410 	val |= (PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
411 	orion5x_pci_hw_wr_conf(bus_nr, 0, func, reg, 4, val | 0x7);
412 }
413 
414 static void __init orion5x_setup_pci_wins(struct mbus_dram_target_info *dram)
415 {
416 	u32 win_enable;
417 	int bus;
418 	int i;
419 
420 	/*
421 	 * First, disable windows.
422 	 */
423 	win_enable = 0xffffffff;
424 	writel(win_enable, PCI_BAR_ENABLE);
425 
426 	/*
427 	 * Setup windows for DDR banks.
428 	 */
429 	bus = orion5x_pci_local_bus_nr();
430 
431 	for (i = 0; i < dram->num_cs; i++) {
432 		struct mbus_dram_window *cs = dram->cs + i;
433 		u32 func = PCI_CONF_FUNC_BAR_CS(cs->cs_index);
434 		u32 reg;
435 		u32 val;
436 
437 		/*
438 		 * Write DRAM bank base address register.
439 		 */
440 		reg = PCI_CONF_REG_BAR_LO_CS(cs->cs_index);
441 		orion5x_pci_hw_rd_conf(bus, 0, func, reg, 4, &val);
442 		val = (cs->base & 0xfffff000) | (val & 0xfff);
443 		orion5x_pci_hw_wr_conf(bus, 0, func, reg, 4, val);
444 
445 		/*
446 		 * Write DRAM bank size register.
447 		 */
448 		reg = PCI_CONF_REG_BAR_HI_CS(cs->cs_index);
449 		orion5x_pci_hw_wr_conf(bus, 0, func, reg, 4, 0);
450 		writel((cs->size - 1) & 0xfffff000,
451 			PCI_BAR_SIZE_DDR_CS(cs->cs_index));
452 		writel(cs->base & 0xfffff000,
453 			PCI_BAR_REMAP_DDR_CS(cs->cs_index));
454 
455 		/*
456 		 * Enable decode window for this chip select.
457 		 */
458 		win_enable &= ~(1 << cs->cs_index);
459 	}
460 
461 	/*
462 	 * Re-enable decode windows.
463 	 */
464 	writel(win_enable, PCI_BAR_ENABLE);
465 
466 	/*
467 	 * Disable automatic update of address remapping when writing to BARs.
468 	 */
469 	orion5x_setbits(PCI_ADDR_DECODE_CTRL, 1);
470 }
471 
472 static int __init pci_setup(struct pci_sys_data *sys)
473 {
474 	struct resource *res;
475 
476 	/*
477 	 * Point PCI unit MBUS decode windows to DRAM space.
478 	 */
479 	orion5x_setup_pci_wins(&orion5x_mbus_dram_info);
480 
481 	/*
482 	 * Master + Slave enable
483 	 */
484 	orion5x_pci_master_slave_enable();
485 
486 	/*
487 	 * Force ordering
488 	 */
489 	orion5x_setbits(PCI_CMD, PCI_CMD_HOST_REORDER);
490 
491 	/*
492 	 * Request resources
493 	 */
494 	res = kzalloc(sizeof(struct resource) * 2, GFP_KERNEL);
495 	if (!res)
496 		panic("pci_setup unable to alloc resources");
497 
498 	/*
499 	 * IORESOURCE_IO
500 	 */
501 	res[0].name = "PCI I/O Space";
502 	res[0].flags = IORESOURCE_IO;
503 	res[0].start = ORION5X_PCI_IO_BUS_BASE;
504 	res[0].end = res[0].start + ORION5X_PCI_IO_SIZE - 1;
505 	if (request_resource(&ioport_resource, &res[0]))
506 		panic("Request PCI IO resource failed\n");
507 	sys->resource[0] = &res[0];
508 
509 	/*
510 	 * IORESOURCE_MEM
511 	 */
512 	res[1].name = "PCI Memory Space";
513 	res[1].flags = IORESOURCE_MEM;
514 	res[1].start = ORION5X_PCI_MEM_PHYS_BASE;
515 	res[1].end = res[1].start + ORION5X_PCI_MEM_SIZE - 1;
516 	if (request_resource(&iomem_resource, &res[1]))
517 		panic("Request PCI Memory resource failed\n");
518 	sys->resource[1] = &res[1];
519 
520 	sys->resource[2] = NULL;
521 	sys->io_offset = 0;
522 
523 	return 1;
524 }
525 
526 
527 /*****************************************************************************
528  * General PCIe + PCI
529  ****************************************************************************/
530 static void __devinit rc_pci_fixup(struct pci_dev *dev)
531 {
532 	/*
533 	 * Prevent enumeration of root complex.
534 	 */
535 	if (dev->bus->parent == NULL && dev->devfn == 0) {
536 		int i;
537 
538 		for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
539 			dev->resource[i].start = 0;
540 			dev->resource[i].end   = 0;
541 			dev->resource[i].flags = 0;
542 		}
543 	}
544 }
545 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MARVELL, PCI_ANY_ID, rc_pci_fixup);
546 
547 static int orion5x_pci_disabled __initdata;
548 
549 void __init orion5x_pci_disable(void)
550 {
551 	orion5x_pci_disabled = 1;
552 }
553 
554 void __init orion5x_pci_set_cardbus_mode(void)
555 {
556 	orion5x_pci_cardbus_mode = 1;
557 }
558 
559 int __init orion5x_pci_sys_setup(int nr, struct pci_sys_data *sys)
560 {
561 	int ret = 0;
562 
563 	vga_base = ORION5X_PCIE_MEM_PHYS_BASE;
564 
565 	if (nr == 0) {
566 		orion_pcie_set_local_bus_nr(PCIE_BASE, sys->busnr);
567 		ret = pcie_setup(sys);
568 	} else if (nr == 1 && !orion5x_pci_disabled) {
569 		orion5x_pci_set_bus_nr(sys->busnr);
570 		ret = pci_setup(sys);
571 	}
572 
573 	return ret;
574 }
575 
576 struct pci_bus __init *orion5x_pci_sys_scan_bus(int nr, struct pci_sys_data *sys)
577 {
578 	struct pci_bus *bus;
579 
580 	if (nr == 0) {
581 		bus = pci_scan_bus(sys->busnr, &pcie_ops, sys);
582 	} else if (nr == 1 && !orion5x_pci_disabled) {
583 		bus = pci_scan_bus(sys->busnr, &pci_ops, sys);
584 	} else {
585 		bus = NULL;
586 		BUG();
587 	}
588 
589 	return bus;
590 }
591 
592 int __init orion5x_pci_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
593 {
594 	int bus = dev->bus->number;
595 
596 	/*
597 	 * PCIe endpoint?
598 	 */
599 	if (orion5x_pci_disabled || bus < orion5x_pci_local_bus_nr())
600 		return IRQ_ORION5X_PCIE0_INT;
601 
602 	return -1;
603 }
604