xref: /openbmc/linux/arch/arm/mach-orion5x/pci.c (revision da1d9caf)
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 "common.h"
23 #include "orion5x.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 	struct resource realio;
146 	int dev;
147 
148 	/*
149 	 * Generic PCIe unit setup.
150 	 */
151 	orion_pcie_setup(PCIE_BASE);
152 
153 	/*
154 	 * Check whether to apply Orion-1/Orion-NAS PCIe config
155 	 * read transaction workaround.
156 	 */
157 	dev = orion_pcie_dev_id(PCIE_BASE);
158 	if (dev == MV88F5181_DEV_ID || dev == MV88F5182_DEV_ID) {
159 		printk(KERN_NOTICE "Applying Orion-1/Orion-NAS PCIe config "
160 				   "read transaction workaround\n");
161 		mvebu_mbus_add_window_by_id(ORION_MBUS_PCIE_WA_TARGET,
162 					    ORION_MBUS_PCIE_WA_ATTR,
163 					    ORION5X_PCIE_WA_PHYS_BASE,
164 					    ORION5X_PCIE_WA_SIZE);
165 		pcie_ops.read = pcie_rd_conf_wa;
166 	}
167 
168 	realio.start = sys->busnr * SZ_64K;
169 	realio.end = realio.start + SZ_64K - 1;
170 	pci_remap_iospace(&realio, ORION5X_PCIE_IO_PHYS_BASE);
171 
172 	/*
173 	 * Request resources.
174 	 */
175 	res = kzalloc(sizeof(struct resource), GFP_KERNEL);
176 	if (!res)
177 		panic("pcie_setup unable to alloc resources");
178 
179 	/*
180 	 * IORESOURCE_MEM
181 	 */
182 	res->name = "PCIe Memory Space";
183 	res->flags = IORESOURCE_MEM;
184 	res->start = ORION5X_PCIE_MEM_PHYS_BASE;
185 	res->end = res->start + ORION5X_PCIE_MEM_SIZE - 1;
186 	if (request_resource(&iomem_resource, res))
187 		panic("Request PCIe Memory resource failed\n");
188 	pci_add_resource_offset(&sys->resources, res, sys->mem_offset);
189 
190 	return 1;
191 }
192 
193 /*****************************************************************************
194  * PCI controller
195  ****************************************************************************/
196 #define ORION5X_PCI_REG(x)	(ORION5X_PCI_VIRT_BASE + (x))
197 #define PCI_MODE		ORION5X_PCI_REG(0xd00)
198 #define PCI_CMD			ORION5X_PCI_REG(0xc00)
199 #define PCI_P2P_CONF		ORION5X_PCI_REG(0x1d14)
200 #define PCI_CONF_ADDR		ORION5X_PCI_REG(0xc78)
201 #define PCI_CONF_DATA		ORION5X_PCI_REG(0xc7c)
202 
203 /*
204  * PCI_MODE bits
205  */
206 #define PCI_MODE_64BIT			(1 << 2)
207 #define PCI_MODE_PCIX			((1 << 4) | (1 << 5))
208 
209 /*
210  * PCI_CMD bits
211  */
212 #define PCI_CMD_HOST_REORDER		(1 << 29)
213 
214 /*
215  * PCI_P2P_CONF bits
216  */
217 #define PCI_P2P_BUS_OFFS		16
218 #define PCI_P2P_BUS_MASK		(0xff << PCI_P2P_BUS_OFFS)
219 #define PCI_P2P_DEV_OFFS		24
220 #define PCI_P2P_DEV_MASK		(0x1f << PCI_P2P_DEV_OFFS)
221 
222 /*
223  * PCI_CONF_ADDR bits
224  */
225 #define PCI_CONF_REG(reg)		((reg) & 0xfc)
226 #define PCI_CONF_FUNC(func)		(((func) & 0x3) << 8)
227 #define PCI_CONF_DEV(dev)		(((dev) & 0x1f) << 11)
228 #define PCI_CONF_BUS(bus)		(((bus) & 0xff) << 16)
229 #define PCI_CONF_ADDR_EN		(1 << 31)
230 
231 /*
232  * Internal configuration space
233  */
234 #define PCI_CONF_FUNC_STAT_CMD		0
235 #define PCI_CONF_REG_STAT_CMD		4
236 #define PCIX_STAT			0x64
237 #define PCIX_STAT_BUS_OFFS		8
238 #define PCIX_STAT_BUS_MASK		(0xff << PCIX_STAT_BUS_OFFS)
239 
240 /*
241  * PCI Address Decode Windows registers
242  */
243 #define PCI_BAR_SIZE_DDR_CS(n)	(((n) == 0) ? ORION5X_PCI_REG(0xc08) : \
244 				 ((n) == 1) ? ORION5X_PCI_REG(0xd08) : \
245 				 ((n) == 2) ? ORION5X_PCI_REG(0xc0c) : \
246 				 ((n) == 3) ? ORION5X_PCI_REG(0xd0c) : NULL)
247 #define PCI_BAR_REMAP_DDR_CS(n)	(((n) == 0) ? ORION5X_PCI_REG(0xc48) : \
248 				 ((n) == 1) ? ORION5X_PCI_REG(0xd48) : \
249 				 ((n) == 2) ? ORION5X_PCI_REG(0xc4c) : \
250 				 ((n) == 3) ? ORION5X_PCI_REG(0xd4c) : NULL)
251 #define PCI_BAR_ENABLE		ORION5X_PCI_REG(0xc3c)
252 #define PCI_ADDR_DECODE_CTRL	ORION5X_PCI_REG(0xd3c)
253 
254 /*
255  * PCI configuration helpers for BAR settings
256  */
257 #define PCI_CONF_FUNC_BAR_CS(n)		((n) >> 1)
258 #define PCI_CONF_REG_BAR_LO_CS(n)	(((n) & 1) ? 0x18 : 0x10)
259 #define PCI_CONF_REG_BAR_HI_CS(n)	(((n) & 1) ? 0x1c : 0x14)
260 
261 /*
262  * PCI config cycles are done by programming the PCI_CONF_ADDR register
263  * and then reading the PCI_CONF_DATA register. Need to make sure these
264  * transactions are atomic.
265  */
266 static DEFINE_SPINLOCK(orion5x_pci_lock);
267 
268 static int orion5x_pci_cardbus_mode;
269 
270 static int orion5x_pci_local_bus_nr(void)
271 {
272 	u32 conf = readl(PCI_P2P_CONF);
273 	return((conf & PCI_P2P_BUS_MASK) >> PCI_P2P_BUS_OFFS);
274 }
275 
276 static int orion5x_pci_hw_rd_conf(int bus, int dev, u32 func,
277 					u32 where, u32 size, u32 *val)
278 {
279 	unsigned long flags;
280 	spin_lock_irqsave(&orion5x_pci_lock, flags);
281 
282 	writel(PCI_CONF_BUS(bus) |
283 		PCI_CONF_DEV(dev) | PCI_CONF_REG(where) |
284 		PCI_CONF_FUNC(func) | PCI_CONF_ADDR_EN, PCI_CONF_ADDR);
285 
286 	*val = readl(PCI_CONF_DATA);
287 
288 	if (size == 1)
289 		*val = (*val >> (8*(where & 0x3))) & 0xff;
290 	else if (size == 2)
291 		*val = (*val >> (8*(where & 0x3))) & 0xffff;
292 
293 	spin_unlock_irqrestore(&orion5x_pci_lock, flags);
294 
295 	return PCIBIOS_SUCCESSFUL;
296 }
297 
298 static int orion5x_pci_hw_wr_conf(int bus, int dev, u32 func,
299 					u32 where, u32 size, u32 val)
300 {
301 	unsigned long flags;
302 	int ret = PCIBIOS_SUCCESSFUL;
303 
304 	spin_lock_irqsave(&orion5x_pci_lock, flags);
305 
306 	writel(PCI_CONF_BUS(bus) |
307 		PCI_CONF_DEV(dev) | PCI_CONF_REG(where) |
308 		PCI_CONF_FUNC(func) | PCI_CONF_ADDR_EN, PCI_CONF_ADDR);
309 
310 	if (size == 4) {
311 		__raw_writel(val, PCI_CONF_DATA);
312 	} else if (size == 2) {
313 		__raw_writew(val, PCI_CONF_DATA + (where & 0x3));
314 	} else if (size == 1) {
315 		__raw_writeb(val, PCI_CONF_DATA + (where & 0x3));
316 	} else {
317 		ret = PCIBIOS_BAD_REGISTER_NUMBER;
318 	}
319 
320 	spin_unlock_irqrestore(&orion5x_pci_lock, flags);
321 
322 	return ret;
323 }
324 
325 static int orion5x_pci_valid_config(int bus, u32 devfn)
326 {
327 	if (bus == orion5x_pci_local_bus_nr()) {
328 		/*
329 		 * Don't go out for local device
330 		 */
331 		if (PCI_SLOT(devfn) == 0 && PCI_FUNC(devfn) != 0)
332 			return 0;
333 
334 		/*
335 		 * When the PCI signals are directly connected to a
336 		 * Cardbus slot, ignore all but device IDs 0 and 1.
337 		 */
338 		if (orion5x_pci_cardbus_mode && PCI_SLOT(devfn) > 1)
339 			return 0;
340 	}
341 
342 	return 1;
343 }
344 
345 static int orion5x_pci_rd_conf(struct pci_bus *bus, u32 devfn,
346 				int where, int size, u32 *val)
347 {
348 	if (!orion5x_pci_valid_config(bus->number, devfn)) {
349 		*val = 0xffffffff;
350 		return PCIBIOS_DEVICE_NOT_FOUND;
351 	}
352 
353 	return orion5x_pci_hw_rd_conf(bus->number, PCI_SLOT(devfn),
354 					PCI_FUNC(devfn), where, size, val);
355 }
356 
357 static int orion5x_pci_wr_conf(struct pci_bus *bus, u32 devfn,
358 				int where, int size, u32 val)
359 {
360 	if (!orion5x_pci_valid_config(bus->number, devfn))
361 		return PCIBIOS_DEVICE_NOT_FOUND;
362 
363 	return orion5x_pci_hw_wr_conf(bus->number, PCI_SLOT(devfn),
364 					PCI_FUNC(devfn), where, size, val);
365 }
366 
367 static struct pci_ops pci_ops = {
368 	.read = orion5x_pci_rd_conf,
369 	.write = orion5x_pci_wr_conf,
370 };
371 
372 static void __init orion5x_pci_set_bus_nr(int nr)
373 {
374 	u32 p2p = readl(PCI_P2P_CONF);
375 
376 	if (readl(PCI_MODE) & PCI_MODE_PCIX) {
377 		/*
378 		 * PCI-X mode
379 		 */
380 		u32 pcix_status, bus, dev;
381 		bus = (p2p & PCI_P2P_BUS_MASK) >> PCI_P2P_BUS_OFFS;
382 		dev = (p2p & PCI_P2P_DEV_MASK) >> PCI_P2P_DEV_OFFS;
383 		orion5x_pci_hw_rd_conf(bus, dev, 0, PCIX_STAT, 4, &pcix_status);
384 		pcix_status &= ~PCIX_STAT_BUS_MASK;
385 		pcix_status |= (nr << PCIX_STAT_BUS_OFFS);
386 		orion5x_pci_hw_wr_conf(bus, dev, 0, PCIX_STAT, 4, pcix_status);
387 	} else {
388 		/*
389 		 * PCI Conventional mode
390 		 */
391 		p2p &= ~PCI_P2P_BUS_MASK;
392 		p2p |= (nr << PCI_P2P_BUS_OFFS);
393 		writel(p2p, PCI_P2P_CONF);
394 	}
395 }
396 
397 static void __init orion5x_pci_master_slave_enable(void)
398 {
399 	int bus_nr, func, reg;
400 	u32 val;
401 
402 	bus_nr = orion5x_pci_local_bus_nr();
403 	func = PCI_CONF_FUNC_STAT_CMD;
404 	reg = PCI_CONF_REG_STAT_CMD;
405 	orion5x_pci_hw_rd_conf(bus_nr, 0, func, reg, 4, &val);
406 	val |= (PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
407 	orion5x_pci_hw_wr_conf(bus_nr, 0, func, reg, 4, val | 0x7);
408 }
409 
410 static void __init orion5x_setup_pci_wins(void)
411 {
412 	const struct mbus_dram_target_info *dram = mv_mbus_dram_info();
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 		const 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 remapping 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 	struct resource realio;
473 
474 	/*
475 	 * Point PCI unit MBUS decode windows to DRAM space.
476 	 */
477 	orion5x_setup_pci_wins();
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 	realio.start = sys->busnr * SZ_64K;
490 	realio.end = realio.start + SZ_64K - 1;
491 	pci_remap_iospace(&realio, ORION5X_PCI_IO_PHYS_BASE);
492 
493 	/*
494 	 * Request resources
495 	 */
496 	res = kzalloc(sizeof(struct resource), GFP_KERNEL);
497 	if (!res)
498 		panic("pci_setup unable to alloc resources");
499 
500 	/*
501 	 * IORESOURCE_MEM
502 	 */
503 	res->name = "PCI Memory Space";
504 	res->flags = IORESOURCE_MEM;
505 	res->start = ORION5X_PCI_MEM_PHYS_BASE;
506 	res->end = res->start + ORION5X_PCI_MEM_SIZE - 1;
507 	if (request_resource(&iomem_resource, res))
508 		panic("Request PCI Memory resource failed\n");
509 	pci_add_resource_offset(&sys->resources, res, sys->mem_offset);
510 
511 	return 1;
512 }
513 
514 
515 /*****************************************************************************
516  * General PCIe + PCI
517  ****************************************************************************/
518 static void rc_pci_fixup(struct pci_dev *dev)
519 {
520 	/*
521 	 * Prevent enumeration of root complex.
522 	 */
523 	if (dev->bus->parent == NULL && dev->devfn == 0) {
524 		int i;
525 
526 		for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
527 			dev->resource[i].start = 0;
528 			dev->resource[i].end   = 0;
529 			dev->resource[i].flags = 0;
530 		}
531 	}
532 }
533 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MARVELL, PCI_ANY_ID, rc_pci_fixup);
534 
535 static int orion5x_pci_disabled __initdata;
536 
537 void __init orion5x_pci_disable(void)
538 {
539 	orion5x_pci_disabled = 1;
540 }
541 
542 void __init orion5x_pci_set_cardbus_mode(void)
543 {
544 	orion5x_pci_cardbus_mode = 1;
545 }
546 
547 int __init orion5x_pci_sys_setup(int nr, struct pci_sys_data *sys)
548 {
549 	vga_base = ORION5X_PCIE_MEM_PHYS_BASE;
550 
551 	if (nr == 0) {
552 		orion_pcie_set_local_bus_nr(PCIE_BASE, sys->busnr);
553 		return pcie_setup(sys);
554 	}
555 
556 	if (nr == 1 && !orion5x_pci_disabled) {
557 		orion5x_pci_set_bus_nr(sys->busnr);
558 		return pci_setup(sys);
559 	}
560 
561 	return 0;
562 }
563 
564 int __init orion5x_pci_sys_scan_bus(int nr, struct pci_host_bridge *bridge)
565 {
566 	struct pci_sys_data *sys = pci_host_bridge_priv(bridge);
567 
568 	list_splice_init(&sys->resources, &bridge->windows);
569 	bridge->dev.parent = NULL;
570 	bridge->sysdata = sys;
571 	bridge->busnr = sys->busnr;
572 
573 	if (nr == 0) {
574 		bridge->ops = &pcie_ops;
575 		return pci_scan_root_bus_bridge(bridge);
576 	}
577 
578 	if (nr == 1 && !orion5x_pci_disabled) {
579 		bridge->ops = &pci_ops;
580 		return pci_scan_root_bus_bridge(bridge);
581 	}
582 
583 	BUG();
584 	return -ENODEV;
585 }
586 
587 int __init orion5x_pci_map_irq(const 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