xref: /openbmc/linux/arch/arm/mach-orion5x/pci.c (revision 5d1190ea)
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 <video/vga.h>
18 #include <asm/irq.h>
19 #include <asm/mach/pci.h>
20 #include <plat/pcie.h>
21 #include <plat/addr-map.h>
22 #include <mach/orion5x.h>
23 #include "common.h"
24 
25 /*****************************************************************************
26  * Orion has one PCIe controller and one PCI controller.
27  *
28  * Note1: The local PCIe bus number is '0'. The local PCI bus number
29  * follows the scanned PCIe bridged busses, if any.
30  *
31  * Note2: It is possible for PCI/PCIe agents to access many subsystem's
32  * space, by configuring BARs and Address Decode Windows, e.g. flashes on
33  * device bus, Orion registers, etc. However this code only enable the
34  * access to DDR banks.
35  ****************************************************************************/
36 
37 
38 /*****************************************************************************
39  * PCIe controller
40  ****************************************************************************/
41 #define PCIE_BASE	(ORION5X_PCIE_VIRT_BASE)
42 
43 void __init orion5x_pcie_id(u32 *dev, u32 *rev)
44 {
45 	*dev = orion_pcie_dev_id(PCIE_BASE);
46 	*rev = orion_pcie_rev(PCIE_BASE);
47 }
48 
49 static int pcie_valid_config(int bus, int dev)
50 {
51 	/*
52 	 * Don't go out when trying to access --
53 	 * 1. nonexisting device on local bus
54 	 * 2. where there's no device connected (no link)
55 	 */
56 	if (bus == 0 && dev == 0)
57 		return 1;
58 
59 	if (!orion_pcie_link_up(PCIE_BASE))
60 		return 0;
61 
62 	if (bus == 0 && dev != 1)
63 		return 0;
64 
65 	return 1;
66 }
67 
68 
69 /*
70  * PCIe config cycles are done by programming the PCIE_CONF_ADDR register
71  * and then reading the PCIE_CONF_DATA register. Need to make sure these
72  * transactions are atomic.
73  */
74 static DEFINE_SPINLOCK(orion5x_pcie_lock);
75 
76 static int pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
77 			int size, u32 *val)
78 {
79 	unsigned long flags;
80 	int ret;
81 
82 	if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0) {
83 		*val = 0xffffffff;
84 		return PCIBIOS_DEVICE_NOT_FOUND;
85 	}
86 
87 	spin_lock_irqsave(&orion5x_pcie_lock, flags);
88 	ret = orion_pcie_rd_conf(PCIE_BASE, bus, devfn, where, size, val);
89 	spin_unlock_irqrestore(&orion5x_pcie_lock, flags);
90 
91 	return ret;
92 }
93 
94 static int pcie_rd_conf_wa(struct pci_bus *bus, u32 devfn,
95 			   int where, int size, u32 *val)
96 {
97 	int ret;
98 
99 	if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0) {
100 		*val = 0xffffffff;
101 		return PCIBIOS_DEVICE_NOT_FOUND;
102 	}
103 
104 	/*
105 	 * We only support access to the non-extended configuration
106 	 * space when using the WA access method (or we would have to
107 	 * sacrifice 256M of CPU virtual address space.)
108 	 */
109 	if (where >= 0x100) {
110 		*val = 0xffffffff;
111 		return PCIBIOS_DEVICE_NOT_FOUND;
112 	}
113 
114 	ret = orion_pcie_rd_conf_wa(ORION5X_PCIE_WA_VIRT_BASE,
115 				    bus, devfn, where, size, val);
116 
117 	return ret;
118 }
119 
120 static int pcie_wr_conf(struct pci_bus *bus, u32 devfn,
121 			int where, int size, u32 val)
122 {
123 	unsigned long flags;
124 	int ret;
125 
126 	if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0)
127 		return PCIBIOS_DEVICE_NOT_FOUND;
128 
129 	spin_lock_irqsave(&orion5x_pcie_lock, flags);
130 	ret = orion_pcie_wr_conf(PCIE_BASE, bus, devfn, where, size, val);
131 	spin_unlock_irqrestore(&orion5x_pcie_lock, flags);
132 
133 	return ret;
134 }
135 
136 static struct pci_ops pcie_ops = {
137 	.read = pcie_rd_conf,
138 	.write = pcie_wr_conf,
139 };
140 
141 
142 static int __init pcie_setup(struct pci_sys_data *sys)
143 {
144 	struct resource *res;
145 	int dev;
146 
147 	/*
148 	 * Generic PCIe unit setup.
149 	 */
150 	orion_pcie_setup(PCIE_BASE);
151 
152 	/*
153 	 * Check whether to apply Orion-1/Orion-NAS PCIe config
154 	 * read transaction workaround.
155 	 */
156 	dev = orion_pcie_dev_id(PCIE_BASE);
157 	if (dev == MV88F5181_DEV_ID || dev == MV88F5182_DEV_ID) {
158 		printk(KERN_NOTICE "Applying Orion-1/Orion-NAS PCIe config "
159 				   "read transaction workaround\n");
160 		mvebu_mbus_add_window_remap_flags("pcie0.0",
161 						  ORION5X_PCIE_WA_PHYS_BASE,
162 						  ORION5X_PCIE_WA_SIZE,
163 						  MVEBU_MBUS_NO_REMAP,
164 						  MVEBU_MBUS_PCI_WA);
165 		pcie_ops.read = pcie_rd_conf_wa;
166 	}
167 
168 	pci_ioremap_io(sys->busnr * SZ_64K, ORION5X_PCIE_IO_PHYS_BASE);
169 
170 	/*
171 	 * Request resources.
172 	 */
173 	res = kzalloc(sizeof(struct resource), GFP_KERNEL);
174 	if (!res)
175 		panic("pcie_setup unable to alloc resources");
176 
177 	/*
178 	 * IORESOURCE_MEM
179 	 */
180 	res->name = "PCIe Memory Space";
181 	res->flags = IORESOURCE_MEM;
182 	res->start = ORION5X_PCIE_MEM_PHYS_BASE;
183 	res->end = res->start + ORION5X_PCIE_MEM_SIZE - 1;
184 	if (request_resource(&iomem_resource, res))
185 		panic("Request PCIe Memory resource failed\n");
186 	pci_add_resource_offset(&sys->resources, res, sys->mem_offset);
187 
188 	return 1;
189 }
190 
191 /*****************************************************************************
192  * PCI controller
193  ****************************************************************************/
194 #define ORION5X_PCI_REG(x)	(ORION5X_PCI_VIRT_BASE + (x))
195 #define PCI_MODE		ORION5X_PCI_REG(0xd00)
196 #define PCI_CMD			ORION5X_PCI_REG(0xc00)
197 #define PCI_P2P_CONF		ORION5X_PCI_REG(0x1d14)
198 #define PCI_CONF_ADDR		ORION5X_PCI_REG(0xc78)
199 #define PCI_CONF_DATA		ORION5X_PCI_REG(0xc7c)
200 
201 /*
202  * PCI_MODE bits
203  */
204 #define PCI_MODE_64BIT			(1 << 2)
205 #define PCI_MODE_PCIX			((1 << 4) | (1 << 5))
206 
207 /*
208  * PCI_CMD bits
209  */
210 #define PCI_CMD_HOST_REORDER		(1 << 29)
211 
212 /*
213  * PCI_P2P_CONF bits
214  */
215 #define PCI_P2P_BUS_OFFS		16
216 #define PCI_P2P_BUS_MASK		(0xff << PCI_P2P_BUS_OFFS)
217 #define PCI_P2P_DEV_OFFS		24
218 #define PCI_P2P_DEV_MASK		(0x1f << PCI_P2P_DEV_OFFS)
219 
220 /*
221  * PCI_CONF_ADDR bits
222  */
223 #define PCI_CONF_REG(reg)		((reg) & 0xfc)
224 #define PCI_CONF_FUNC(func)		(((func) & 0x3) << 8)
225 #define PCI_CONF_DEV(dev)		(((dev) & 0x1f) << 11)
226 #define PCI_CONF_BUS(bus)		(((bus) & 0xff) << 16)
227 #define PCI_CONF_ADDR_EN		(1 << 31)
228 
229 /*
230  * Internal configuration space
231  */
232 #define PCI_CONF_FUNC_STAT_CMD		0
233 #define PCI_CONF_REG_STAT_CMD		4
234 #define PCIX_STAT			0x64
235 #define PCIX_STAT_BUS_OFFS		8
236 #define PCIX_STAT_BUS_MASK		(0xff << PCIX_STAT_BUS_OFFS)
237 
238 /*
239  * PCI Address Decode Windows registers
240  */
241 #define PCI_BAR_SIZE_DDR_CS(n)	(((n) == 0) ? ORION5X_PCI_REG(0xc08) : \
242 				 ((n) == 1) ? ORION5X_PCI_REG(0xd08) : \
243 				 ((n) == 2) ? ORION5X_PCI_REG(0xc0c) : \
244 				 ((n) == 3) ? ORION5X_PCI_REG(0xd0c) : 0)
245 #define PCI_BAR_REMAP_DDR_CS(n)	(((n) == 0) ? ORION5X_PCI_REG(0xc48) : \
246 				 ((n) == 1) ? ORION5X_PCI_REG(0xd48) : \
247 				 ((n) == 2) ? ORION5X_PCI_REG(0xc4c) : \
248 				 ((n) == 3) ? ORION5X_PCI_REG(0xd4c) : 0)
249 #define PCI_BAR_ENABLE		ORION5X_PCI_REG(0xc3c)
250 #define PCI_ADDR_DECODE_CTRL	ORION5X_PCI_REG(0xd3c)
251 
252 /*
253  * PCI configuration helpers for BAR settings
254  */
255 #define PCI_CONF_FUNC_BAR_CS(n)		((n) >> 1)
256 #define PCI_CONF_REG_BAR_LO_CS(n)	(((n) & 1) ? 0x18 : 0x10)
257 #define PCI_CONF_REG_BAR_HI_CS(n)	(((n) & 1) ? 0x1c : 0x14)
258 
259 /*
260  * PCI config cycles are done by programming the PCI_CONF_ADDR register
261  * and then reading the PCI_CONF_DATA register. Need to make sure these
262  * transactions are atomic.
263  */
264 static DEFINE_SPINLOCK(orion5x_pci_lock);
265 
266 static int orion5x_pci_cardbus_mode;
267 
268 static int orion5x_pci_local_bus_nr(void)
269 {
270 	u32 conf = readl(PCI_P2P_CONF);
271 	return((conf & PCI_P2P_BUS_MASK) >> PCI_P2P_BUS_OFFS);
272 }
273 
274 static int orion5x_pci_hw_rd_conf(int bus, int dev, u32 func,
275 					u32 where, u32 size, u32 *val)
276 {
277 	unsigned long flags;
278 	spin_lock_irqsave(&orion5x_pci_lock, flags);
279 
280 	writel(PCI_CONF_BUS(bus) |
281 		PCI_CONF_DEV(dev) | PCI_CONF_REG(where) |
282 		PCI_CONF_FUNC(func) | PCI_CONF_ADDR_EN, PCI_CONF_ADDR);
283 
284 	*val = readl(PCI_CONF_DATA);
285 
286 	if (size == 1)
287 		*val = (*val >> (8*(where & 0x3))) & 0xff;
288 	else if (size == 2)
289 		*val = (*val >> (8*(where & 0x3))) & 0xffff;
290 
291 	spin_unlock_irqrestore(&orion5x_pci_lock, flags);
292 
293 	return PCIBIOS_SUCCESSFUL;
294 }
295 
296 static int orion5x_pci_hw_wr_conf(int bus, int dev, u32 func,
297 					u32 where, u32 size, u32 val)
298 {
299 	unsigned long flags;
300 	int ret = PCIBIOS_SUCCESSFUL;
301 
302 	spin_lock_irqsave(&orion5x_pci_lock, flags);
303 
304 	writel(PCI_CONF_BUS(bus) |
305 		PCI_CONF_DEV(dev) | PCI_CONF_REG(where) |
306 		PCI_CONF_FUNC(func) | PCI_CONF_ADDR_EN, PCI_CONF_ADDR);
307 
308 	if (size == 4) {
309 		__raw_writel(val, PCI_CONF_DATA);
310 	} else if (size == 2) {
311 		__raw_writew(val, PCI_CONF_DATA + (where & 0x3));
312 	} else if (size == 1) {
313 		__raw_writeb(val, PCI_CONF_DATA + (where & 0x3));
314 	} else {
315 		ret = PCIBIOS_BAD_REGISTER_NUMBER;
316 	}
317 
318 	spin_unlock_irqrestore(&orion5x_pci_lock, flags);
319 
320 	return ret;
321 }
322 
323 static int orion5x_pci_valid_config(int bus, u32 devfn)
324 {
325 	if (bus == orion5x_pci_local_bus_nr()) {
326 		/*
327 		 * Don't go out for local device
328 		 */
329 		if (PCI_SLOT(devfn) == 0 && PCI_FUNC(devfn) != 0)
330 			return 0;
331 
332 		/*
333 		 * When the PCI signals are directly connected to a
334 		 * Cardbus slot, ignore all but device IDs 0 and 1.
335 		 */
336 		if (orion5x_pci_cardbus_mode && PCI_SLOT(devfn) > 1)
337 			return 0;
338 	}
339 
340 	return 1;
341 }
342 
343 static int orion5x_pci_rd_conf(struct pci_bus *bus, u32 devfn,
344 				int where, int size, u32 *val)
345 {
346 	if (!orion5x_pci_valid_config(bus->number, devfn)) {
347 		*val = 0xffffffff;
348 		return PCIBIOS_DEVICE_NOT_FOUND;
349 	}
350 
351 	return orion5x_pci_hw_rd_conf(bus->number, PCI_SLOT(devfn),
352 					PCI_FUNC(devfn), where, size, val);
353 }
354 
355 static int orion5x_pci_wr_conf(struct pci_bus *bus, u32 devfn,
356 				int where, int size, u32 val)
357 {
358 	if (!orion5x_pci_valid_config(bus->number, devfn))
359 		return PCIBIOS_DEVICE_NOT_FOUND;
360 
361 	return orion5x_pci_hw_wr_conf(bus->number, PCI_SLOT(devfn),
362 					PCI_FUNC(devfn), where, size, val);
363 }
364 
365 static struct pci_ops pci_ops = {
366 	.read = orion5x_pci_rd_conf,
367 	.write = orion5x_pci_wr_conf,
368 };
369 
370 static void __init orion5x_pci_set_bus_nr(int nr)
371 {
372 	u32 p2p = readl(PCI_P2P_CONF);
373 
374 	if (readl(PCI_MODE) & PCI_MODE_PCIX) {
375 		/*
376 		 * PCI-X mode
377 		 */
378 		u32 pcix_status, bus, dev;
379 		bus = (p2p & PCI_P2P_BUS_MASK) >> PCI_P2P_BUS_OFFS;
380 		dev = (p2p & PCI_P2P_DEV_MASK) >> PCI_P2P_DEV_OFFS;
381 		orion5x_pci_hw_rd_conf(bus, dev, 0, PCIX_STAT, 4, &pcix_status);
382 		pcix_status &= ~PCIX_STAT_BUS_MASK;
383 		pcix_status |= (nr << PCIX_STAT_BUS_OFFS);
384 		orion5x_pci_hw_wr_conf(bus, dev, 0, PCIX_STAT, 4, pcix_status);
385 	} else {
386 		/*
387 		 * PCI Conventional mode
388 		 */
389 		p2p &= ~PCI_P2P_BUS_MASK;
390 		p2p |= (nr << PCI_P2P_BUS_OFFS);
391 		writel(p2p, PCI_P2P_CONF);
392 	}
393 }
394 
395 static void __init orion5x_pci_master_slave_enable(void)
396 {
397 	int bus_nr, func, reg;
398 	u32 val;
399 
400 	bus_nr = orion5x_pci_local_bus_nr();
401 	func = PCI_CONF_FUNC_STAT_CMD;
402 	reg = PCI_CONF_REG_STAT_CMD;
403 	orion5x_pci_hw_rd_conf(bus_nr, 0, func, reg, 4, &val);
404 	val |= (PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
405 	orion5x_pci_hw_wr_conf(bus_nr, 0, func, reg, 4, val | 0x7);
406 }
407 
408 static void __init orion5x_setup_pci_wins(void)
409 {
410 	const struct mbus_dram_target_info *dram = mv_mbus_dram_info();
411 	u32 win_enable;
412 	int bus;
413 	int i;
414 
415 	/*
416 	 * First, disable windows.
417 	 */
418 	win_enable = 0xffffffff;
419 	writel(win_enable, PCI_BAR_ENABLE);
420 
421 	/*
422 	 * Setup windows for DDR banks.
423 	 */
424 	bus = orion5x_pci_local_bus_nr();
425 
426 	for (i = 0; i < dram->num_cs; i++) {
427 		const struct mbus_dram_window *cs = dram->cs + i;
428 		u32 func = PCI_CONF_FUNC_BAR_CS(cs->cs_index);
429 		u32 reg;
430 		u32 val;
431 
432 		/*
433 		 * Write DRAM bank base address register.
434 		 */
435 		reg = PCI_CONF_REG_BAR_LO_CS(cs->cs_index);
436 		orion5x_pci_hw_rd_conf(bus, 0, func, reg, 4, &val);
437 		val = (cs->base & 0xfffff000) | (val & 0xfff);
438 		orion5x_pci_hw_wr_conf(bus, 0, func, reg, 4, val);
439 
440 		/*
441 		 * Write DRAM bank size register.
442 		 */
443 		reg = PCI_CONF_REG_BAR_HI_CS(cs->cs_index);
444 		orion5x_pci_hw_wr_conf(bus, 0, func, reg, 4, 0);
445 		writel((cs->size - 1) & 0xfffff000,
446 			PCI_BAR_SIZE_DDR_CS(cs->cs_index));
447 		writel(cs->base & 0xfffff000,
448 			PCI_BAR_REMAP_DDR_CS(cs->cs_index));
449 
450 		/*
451 		 * Enable decode window for this chip select.
452 		 */
453 		win_enable &= ~(1 << cs->cs_index);
454 	}
455 
456 	/*
457 	 * Re-enable decode windows.
458 	 */
459 	writel(win_enable, PCI_BAR_ENABLE);
460 
461 	/*
462 	 * Disable automatic update of address remapping when writing to BARs.
463 	 */
464 	orion5x_setbits(PCI_ADDR_DECODE_CTRL, 1);
465 }
466 
467 static int __init pci_setup(struct pci_sys_data *sys)
468 {
469 	struct resource *res;
470 
471 	/*
472 	 * Point PCI unit MBUS decode windows to DRAM space.
473 	 */
474 	orion5x_setup_pci_wins();
475 
476 	/*
477 	 * Master + Slave enable
478 	 */
479 	orion5x_pci_master_slave_enable();
480 
481 	/*
482 	 * Force ordering
483 	 */
484 	orion5x_setbits(PCI_CMD, PCI_CMD_HOST_REORDER);
485 
486 	pci_ioremap_io(sys->busnr * SZ_64K, ORION5X_PCI_IO_PHYS_BASE);
487 
488 	/*
489 	 * Request resources
490 	 */
491 	res = kzalloc(sizeof(struct resource), GFP_KERNEL);
492 	if (!res)
493 		panic("pci_setup unable to alloc resources");
494 
495 	/*
496 	 * IORESOURCE_MEM
497 	 */
498 	res->name = "PCI Memory Space";
499 	res->flags = IORESOURCE_MEM;
500 	res->start = ORION5X_PCI_MEM_PHYS_BASE;
501 	res->end = res->start + ORION5X_PCI_MEM_SIZE - 1;
502 	if (request_resource(&iomem_resource, res))
503 		panic("Request PCI Memory resource failed\n");
504 	pci_add_resource_offset(&sys->resources, res, sys->mem_offset);
505 
506 	return 1;
507 }
508 
509 
510 /*****************************************************************************
511  * General PCIe + PCI
512  ****************************************************************************/
513 static void rc_pci_fixup(struct pci_dev *dev)
514 {
515 	/*
516 	 * Prevent enumeration of root complex.
517 	 */
518 	if (dev->bus->parent == NULL && dev->devfn == 0) {
519 		int i;
520 
521 		for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
522 			dev->resource[i].start = 0;
523 			dev->resource[i].end   = 0;
524 			dev->resource[i].flags = 0;
525 		}
526 	}
527 }
528 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MARVELL, PCI_ANY_ID, rc_pci_fixup);
529 
530 static int orion5x_pci_disabled __initdata;
531 
532 void __init orion5x_pci_disable(void)
533 {
534 	orion5x_pci_disabled = 1;
535 }
536 
537 void __init orion5x_pci_set_cardbus_mode(void)
538 {
539 	orion5x_pci_cardbus_mode = 1;
540 }
541 
542 int __init orion5x_pci_sys_setup(int nr, struct pci_sys_data *sys)
543 {
544 	int ret = 0;
545 
546 	vga_base = ORION5X_PCIE_MEM_PHYS_BASE;
547 
548 	if (nr == 0) {
549 		orion_pcie_set_local_bus_nr(PCIE_BASE, sys->busnr);
550 		ret = pcie_setup(sys);
551 	} else if (nr == 1 && !orion5x_pci_disabled) {
552 		orion5x_pci_set_bus_nr(sys->busnr);
553 		ret = pci_setup(sys);
554 	}
555 
556 	return ret;
557 }
558 
559 struct pci_bus __init *orion5x_pci_sys_scan_bus(int nr, struct pci_sys_data *sys)
560 {
561 	struct pci_bus *bus;
562 
563 	if (nr == 0) {
564 		bus = pci_scan_root_bus(NULL, sys->busnr, &pcie_ops, sys,
565 					&sys->resources);
566 	} else if (nr == 1 && !orion5x_pci_disabled) {
567 		bus = pci_scan_root_bus(NULL, sys->busnr, &pci_ops, sys,
568 					&sys->resources);
569 	} else {
570 		bus = NULL;
571 		BUG();
572 	}
573 
574 	return bus;
575 }
576 
577 int __init orion5x_pci_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
578 {
579 	int bus = dev->bus->number;
580 
581 	/*
582 	 * PCIe endpoint?
583 	 */
584 	if (orion5x_pci_disabled || bus < orion5x_pci_local_bus_nr())
585 		return IRQ_ORION5X_PCIE0_INT;
586 
587 	return -1;
588 }
589