xref: /openbmc/linux/arch/arm/mach-orion5x/pci.c (revision 63a9332b)
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 
24 /*****************************************************************************
25  * Orion has one PCIe controller and one PCI controller.
26  *
27  * Note1: The local PCIe bus number is '0'. The local PCI bus number
28  * follows the scanned PCIe bridged busses, if any.
29  *
30  * Note2: It is possible for PCI/PCIe agents to access many subsystem's
31  * space, by configuring BARs and Address Decode Windows, e.g. flashes on
32  * device bus, Orion registers, etc. However this code only enable the
33  * access to DDR banks.
34  ****************************************************************************/
35 
36 
37 /*****************************************************************************
38  * PCIe controller
39  ****************************************************************************/
40 #define PCIE_BASE	((void __iomem *)ORION5X_PCIE_VIRT_BASE)
41 
42 void __init orion5x_pcie_id(u32 *dev, u32 *rev)
43 {
44 	*dev = orion_pcie_dev_id(PCIE_BASE);
45 	*rev = orion_pcie_rev(PCIE_BASE);
46 }
47 
48 static int pcie_valid_config(int bus, int dev)
49 {
50 	/*
51 	 * Don't go out when trying to access --
52 	 * 1. nonexisting device on local bus
53 	 * 2. where there's no device connected (no link)
54 	 */
55 	if (bus == 0 && dev == 0)
56 		return 1;
57 
58 	if (!orion_pcie_link_up(PCIE_BASE))
59 		return 0;
60 
61 	if (bus == 0 && dev != 1)
62 		return 0;
63 
64 	return 1;
65 }
66 
67 
68 /*
69  * PCIe config cycles are done by programming the PCIE_CONF_ADDR register
70  * and then reading the PCIE_CONF_DATA register. Need to make sure these
71  * transactions are atomic.
72  */
73 static DEFINE_SPINLOCK(orion5x_pcie_lock);
74 
75 static int pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
76 			int size, u32 *val)
77 {
78 	unsigned long flags;
79 	int ret;
80 
81 	if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0) {
82 		*val = 0xffffffff;
83 		return PCIBIOS_DEVICE_NOT_FOUND;
84 	}
85 
86 	spin_lock_irqsave(&orion5x_pcie_lock, flags);
87 	ret = orion_pcie_rd_conf(PCIE_BASE, bus, devfn, where, size, val);
88 	spin_unlock_irqrestore(&orion5x_pcie_lock, flags);
89 
90 	return ret;
91 }
92 
93 static int pcie_rd_conf_wa(struct pci_bus *bus, u32 devfn,
94 			   int where, int size, u32 *val)
95 {
96 	int ret;
97 
98 	if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0) {
99 		*val = 0xffffffff;
100 		return PCIBIOS_DEVICE_NOT_FOUND;
101 	}
102 
103 	/*
104 	 * We only support access to the non-extended configuration
105 	 * space when using the WA access method (or we would have to
106 	 * sacrifice 256M of CPU virtual address space.)
107 	 */
108 	if (where >= 0x100) {
109 		*val = 0xffffffff;
110 		return PCIBIOS_DEVICE_NOT_FOUND;
111 	}
112 
113 	ret = orion_pcie_rd_conf_wa((void __iomem *)ORION5X_PCIE_WA_VIRT_BASE,
114 				    bus, devfn, where, size, val);
115 
116 	return ret;
117 }
118 
119 static int pcie_wr_conf(struct pci_bus *bus, u32 devfn,
120 			int where, int size, u32 val)
121 {
122 	unsigned long flags;
123 	int ret;
124 
125 	if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0)
126 		return PCIBIOS_DEVICE_NOT_FOUND;
127 
128 	spin_lock_irqsave(&orion5x_pcie_lock, flags);
129 	ret = orion_pcie_wr_conf(PCIE_BASE, bus, devfn, where, size, val);
130 	spin_unlock_irqrestore(&orion5x_pcie_lock, flags);
131 
132 	return ret;
133 }
134 
135 static struct pci_ops pcie_ops = {
136 	.read = pcie_rd_conf,
137 	.write = pcie_wr_conf,
138 };
139 
140 
141 static int __init pcie_setup(struct pci_sys_data *sys)
142 {
143 	struct resource *res;
144 	int dev;
145 
146 	/*
147 	 * Generic PCIe unit setup.
148 	 */
149 	orion_pcie_setup(PCIE_BASE);
150 
151 	/*
152 	 * Check whether to apply Orion-1/Orion-NAS PCIe config
153 	 * read transaction workaround.
154 	 */
155 	dev = orion_pcie_dev_id(PCIE_BASE);
156 	if (dev == MV88F5181_DEV_ID || dev == MV88F5182_DEV_ID) {
157 		printk(KERN_NOTICE "Applying Orion-1/Orion-NAS PCIe config "
158 				   "read transaction workaround\n");
159 		orion5x_setup_pcie_wa_win(ORION5X_PCIE_WA_PHYS_BASE,
160 					  ORION5X_PCIE_WA_SIZE);
161 		pcie_ops.read = pcie_rd_conf_wa;
162 	}
163 
164 	/*
165 	 * Request resources.
166 	 */
167 	res = kzalloc(sizeof(struct resource) * 2, GFP_KERNEL);
168 	if (!res)
169 		panic("pcie_setup unable to alloc resources");
170 
171 	/*
172 	 * IORESOURCE_IO
173 	 */
174 	res[0].name = "PCIe I/O Space";
175 	res[0].flags = IORESOURCE_IO;
176 	res[0].start = ORION5X_PCIE_IO_BUS_BASE;
177 	res[0].end = res[0].start + ORION5X_PCIE_IO_SIZE - 1;
178 	if (request_resource(&ioport_resource, &res[0]))
179 		panic("Request PCIe IO resource failed\n");
180 	sys->resource[0] = &res[0];
181 
182 	/*
183 	 * IORESOURCE_MEM
184 	 */
185 	res[1].name = "PCIe Memory Space";
186 	res[1].flags = IORESOURCE_MEM;
187 	res[1].start = ORION5X_PCIE_MEM_PHYS_BASE;
188 	res[1].end = res[1].start + ORION5X_PCIE_MEM_SIZE - 1;
189 	if (request_resource(&iomem_resource, &res[1]))
190 		panic("Request PCIe Memory resource failed\n");
191 	sys->resource[1] = &res[1];
192 
193 	sys->resource[2] = NULL;
194 	sys->io_offset = 0;
195 
196 	return 1;
197 }
198 
199 /*****************************************************************************
200  * PCI controller
201  ****************************************************************************/
202 #define ORION5X_PCI_REG(x)	(ORION5X_PCI_VIRT_BASE | (x))
203 #define PCI_MODE		ORION5X_PCI_REG(0xd00)
204 #define PCI_CMD			ORION5X_PCI_REG(0xc00)
205 #define PCI_P2P_CONF		ORION5X_PCI_REG(0x1d14)
206 #define PCI_CONF_ADDR		ORION5X_PCI_REG(0xc78)
207 #define PCI_CONF_DATA		ORION5X_PCI_REG(0xc7c)
208 
209 /*
210  * PCI_MODE bits
211  */
212 #define PCI_MODE_64BIT			(1 << 2)
213 #define PCI_MODE_PCIX			((1 << 4) | (1 << 5))
214 
215 /*
216  * PCI_CMD bits
217  */
218 #define PCI_CMD_HOST_REORDER		(1 << 29)
219 
220 /*
221  * PCI_P2P_CONF bits
222  */
223 #define PCI_P2P_BUS_OFFS		16
224 #define PCI_P2P_BUS_MASK		(0xff << PCI_P2P_BUS_OFFS)
225 #define PCI_P2P_DEV_OFFS		24
226 #define PCI_P2P_DEV_MASK		(0x1f << PCI_P2P_DEV_OFFS)
227 
228 /*
229  * PCI_CONF_ADDR bits
230  */
231 #define PCI_CONF_REG(reg)		((reg) & 0xfc)
232 #define PCI_CONF_FUNC(func)		(((func) & 0x3) << 8)
233 #define PCI_CONF_DEV(dev)		(((dev) & 0x1f) << 11)
234 #define PCI_CONF_BUS(bus)		(((bus) & 0xff) << 16)
235 #define PCI_CONF_ADDR_EN		(1 << 31)
236 
237 /*
238  * Internal configuration space
239  */
240 #define PCI_CONF_FUNC_STAT_CMD		0
241 #define PCI_CONF_REG_STAT_CMD		4
242 #define PCIX_STAT			0x64
243 #define PCIX_STAT_BUS_OFFS		8
244 #define PCIX_STAT_BUS_MASK		(0xff << PCIX_STAT_BUS_OFFS)
245 
246 /*
247  * PCI Address Decode Windows registers
248  */
249 #define PCI_BAR_SIZE_DDR_CS(n)	(((n) == 0) ? ORION5X_PCI_REG(0xc08) : \
250 				 ((n) == 1) ? ORION5X_PCI_REG(0xd08) : \
251 				 ((n) == 2) ? ORION5X_PCI_REG(0xc0c) : \
252 				 ((n) == 3) ? ORION5X_PCI_REG(0xd0c) : 0)
253 #define PCI_BAR_REMAP_DDR_CS(n)	(((n) == 0) ? ORION5X_PCI_REG(0xc48) : \
254 				 ((n) == 1) ? ORION5X_PCI_REG(0xd48) : \
255 				 ((n) == 2) ? ORION5X_PCI_REG(0xc4c) : \
256 				 ((n) == 3) ? ORION5X_PCI_REG(0xd4c) : 0)
257 #define PCI_BAR_ENABLE		ORION5X_PCI_REG(0xc3c)
258 #define PCI_ADDR_DECODE_CTRL	ORION5X_PCI_REG(0xd3c)
259 
260 /*
261  * PCI configuration helpers for BAR settings
262  */
263 #define PCI_CONF_FUNC_BAR_CS(n)		((n) >> 1)
264 #define PCI_CONF_REG_BAR_LO_CS(n)	(((n) & 1) ? 0x18 : 0x10)
265 #define PCI_CONF_REG_BAR_HI_CS(n)	(((n) & 1) ? 0x1c : 0x14)
266 
267 /*
268  * PCI config cycles are done by programming the PCI_CONF_ADDR register
269  * and then reading the PCI_CONF_DATA register. Need to make sure these
270  * transactions are atomic.
271  */
272 static DEFINE_SPINLOCK(orion5x_pci_lock);
273 
274 static int orion5x_pci_cardbus_mode;
275 
276 static int orion5x_pci_local_bus_nr(void)
277 {
278 	u32 conf = readl(PCI_P2P_CONF);
279 	return((conf & PCI_P2P_BUS_MASK) >> PCI_P2P_BUS_OFFS);
280 }
281 
282 static int orion5x_pci_hw_rd_conf(int bus, int dev, u32 func,
283 					u32 where, u32 size, u32 *val)
284 {
285 	unsigned long flags;
286 	spin_lock_irqsave(&orion5x_pci_lock, flags);
287 
288 	writel(PCI_CONF_BUS(bus) |
289 		PCI_CONF_DEV(dev) | PCI_CONF_REG(where) |
290 		PCI_CONF_FUNC(func) | PCI_CONF_ADDR_EN, PCI_CONF_ADDR);
291 
292 	*val = readl(PCI_CONF_DATA);
293 
294 	if (size == 1)
295 		*val = (*val >> (8*(where & 0x3))) & 0xff;
296 	else if (size == 2)
297 		*val = (*val >> (8*(where & 0x3))) & 0xffff;
298 
299 	spin_unlock_irqrestore(&orion5x_pci_lock, flags);
300 
301 	return PCIBIOS_SUCCESSFUL;
302 }
303 
304 static int orion5x_pci_hw_wr_conf(int bus, int dev, u32 func,
305 					u32 where, u32 size, u32 val)
306 {
307 	unsigned long flags;
308 	int ret = PCIBIOS_SUCCESSFUL;
309 
310 	spin_lock_irqsave(&orion5x_pci_lock, flags);
311 
312 	writel(PCI_CONF_BUS(bus) |
313 		PCI_CONF_DEV(dev) | PCI_CONF_REG(where) |
314 		PCI_CONF_FUNC(func) | PCI_CONF_ADDR_EN, PCI_CONF_ADDR);
315 
316 	if (size == 4) {
317 		__raw_writel(val, PCI_CONF_DATA);
318 	} else if (size == 2) {
319 		__raw_writew(val, PCI_CONF_DATA + (where & 0x3));
320 	} else if (size == 1) {
321 		__raw_writeb(val, PCI_CONF_DATA + (where & 0x3));
322 	} else {
323 		ret = PCIBIOS_BAD_REGISTER_NUMBER;
324 	}
325 
326 	spin_unlock_irqrestore(&orion5x_pci_lock, flags);
327 
328 	return ret;
329 }
330 
331 static int orion5x_pci_valid_config(int bus, u32 devfn)
332 {
333 	if (bus == orion5x_pci_local_bus_nr()) {
334 		/*
335 		 * Don't go out for local device
336 		 */
337 		if (PCI_SLOT(devfn) == 0 && PCI_FUNC(devfn) != 0)
338 			return 0;
339 
340 		/*
341 		 * When the PCI signals are directly connected to a
342 		 * Cardbus slot, ignore all but device IDs 0 and 1.
343 		 */
344 		if (orion5x_pci_cardbus_mode && PCI_SLOT(devfn) > 1)
345 			return 0;
346 	}
347 
348 	return 1;
349 }
350 
351 static int orion5x_pci_rd_conf(struct pci_bus *bus, u32 devfn,
352 				int where, int size, u32 *val)
353 {
354 	if (!orion5x_pci_valid_config(bus->number, devfn)) {
355 		*val = 0xffffffff;
356 		return PCIBIOS_DEVICE_NOT_FOUND;
357 	}
358 
359 	return orion5x_pci_hw_rd_conf(bus->number, PCI_SLOT(devfn),
360 					PCI_FUNC(devfn), where, size, val);
361 }
362 
363 static int orion5x_pci_wr_conf(struct pci_bus *bus, u32 devfn,
364 				int where, int size, u32 val)
365 {
366 	if (!orion5x_pci_valid_config(bus->number, devfn))
367 		return PCIBIOS_DEVICE_NOT_FOUND;
368 
369 	return orion5x_pci_hw_wr_conf(bus->number, PCI_SLOT(devfn),
370 					PCI_FUNC(devfn), where, size, val);
371 }
372 
373 static struct pci_ops pci_ops = {
374 	.read = orion5x_pci_rd_conf,
375 	.write = orion5x_pci_wr_conf,
376 };
377 
378 static void __init orion5x_pci_set_bus_nr(int nr)
379 {
380 	u32 p2p = readl(PCI_P2P_CONF);
381 
382 	if (readl(PCI_MODE) & PCI_MODE_PCIX) {
383 		/*
384 		 * PCI-X mode
385 		 */
386 		u32 pcix_status, bus, dev;
387 		bus = (p2p & PCI_P2P_BUS_MASK) >> PCI_P2P_BUS_OFFS;
388 		dev = (p2p & PCI_P2P_DEV_MASK) >> PCI_P2P_DEV_OFFS;
389 		orion5x_pci_hw_rd_conf(bus, dev, 0, PCIX_STAT, 4, &pcix_status);
390 		pcix_status &= ~PCIX_STAT_BUS_MASK;
391 		pcix_status |= (nr << PCIX_STAT_BUS_OFFS);
392 		orion5x_pci_hw_wr_conf(bus, dev, 0, PCIX_STAT, 4, pcix_status);
393 	} else {
394 		/*
395 		 * PCI Conventional mode
396 		 */
397 		p2p &= ~PCI_P2P_BUS_MASK;
398 		p2p |= (nr << PCI_P2P_BUS_OFFS);
399 		writel(p2p, PCI_P2P_CONF);
400 	}
401 }
402 
403 static void __init orion5x_pci_master_slave_enable(void)
404 {
405 	int bus_nr, func, reg;
406 	u32 val;
407 
408 	bus_nr = orion5x_pci_local_bus_nr();
409 	func = PCI_CONF_FUNC_STAT_CMD;
410 	reg = PCI_CONF_REG_STAT_CMD;
411 	orion5x_pci_hw_rd_conf(bus_nr, 0, func, reg, 4, &val);
412 	val |= (PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
413 	orion5x_pci_hw_wr_conf(bus_nr, 0, func, reg, 4, val | 0x7);
414 }
415 
416 static void __init orion5x_setup_pci_wins(struct mbus_dram_target_info *dram)
417 {
418 	u32 win_enable;
419 	int bus;
420 	int i;
421 
422 	/*
423 	 * First, disable windows.
424 	 */
425 	win_enable = 0xffffffff;
426 	writel(win_enable, PCI_BAR_ENABLE);
427 
428 	/*
429 	 * Setup windows for DDR banks.
430 	 */
431 	bus = orion5x_pci_local_bus_nr();
432 
433 	for (i = 0; i < dram->num_cs; i++) {
434 		struct mbus_dram_window *cs = dram->cs + i;
435 		u32 func = PCI_CONF_FUNC_BAR_CS(cs->cs_index);
436 		u32 reg;
437 		u32 val;
438 
439 		/*
440 		 * Write DRAM bank base address register.
441 		 */
442 		reg = PCI_CONF_REG_BAR_LO_CS(cs->cs_index);
443 		orion5x_pci_hw_rd_conf(bus, 0, func, reg, 4, &val);
444 		val = (cs->base & 0xfffff000) | (val & 0xfff);
445 		orion5x_pci_hw_wr_conf(bus, 0, func, reg, 4, val);
446 
447 		/*
448 		 * Write DRAM bank size register.
449 		 */
450 		reg = PCI_CONF_REG_BAR_HI_CS(cs->cs_index);
451 		orion5x_pci_hw_wr_conf(bus, 0, func, reg, 4, 0);
452 		writel((cs->size - 1) & 0xfffff000,
453 			PCI_BAR_SIZE_DDR_CS(cs->cs_index));
454 		writel(cs->base & 0xfffff000,
455 			PCI_BAR_REMAP_DDR_CS(cs->cs_index));
456 
457 		/*
458 		 * Enable decode window for this chip select.
459 		 */
460 		win_enable &= ~(1 << cs->cs_index);
461 	}
462 
463 	/*
464 	 * Re-enable decode windows.
465 	 */
466 	writel(win_enable, PCI_BAR_ENABLE);
467 
468 	/*
469 	 * Disable automatic update of address remapping when writing to BARs.
470 	 */
471 	orion5x_setbits(PCI_ADDR_DECODE_CTRL, 1);
472 }
473 
474 static int __init pci_setup(struct pci_sys_data *sys)
475 {
476 	struct resource *res;
477 
478 	/*
479 	 * Point PCI unit MBUS decode windows to DRAM space.
480 	 */
481 	orion5x_setup_pci_wins(&orion_mbus_dram_info);
482 
483 	/*
484 	 * Master + Slave enable
485 	 */
486 	orion5x_pci_master_slave_enable();
487 
488 	/*
489 	 * Force ordering
490 	 */
491 	orion5x_setbits(PCI_CMD, PCI_CMD_HOST_REORDER);
492 
493 	/*
494 	 * Request resources
495 	 */
496 	res = kzalloc(sizeof(struct resource) * 2, GFP_KERNEL);
497 	if (!res)
498 		panic("pci_setup unable to alloc resources");
499 
500 	/*
501 	 * IORESOURCE_IO
502 	 */
503 	res[0].name = "PCI I/O Space";
504 	res[0].flags = IORESOURCE_IO;
505 	res[0].start = ORION5X_PCI_IO_BUS_BASE;
506 	res[0].end = res[0].start + ORION5X_PCI_IO_SIZE - 1;
507 	if (request_resource(&ioport_resource, &res[0]))
508 		panic("Request PCI IO resource failed\n");
509 	sys->resource[0] = &res[0];
510 
511 	/*
512 	 * IORESOURCE_MEM
513 	 */
514 	res[1].name = "PCI Memory Space";
515 	res[1].flags = IORESOURCE_MEM;
516 	res[1].start = ORION5X_PCI_MEM_PHYS_BASE;
517 	res[1].end = res[1].start + ORION5X_PCI_MEM_SIZE - 1;
518 	if (request_resource(&iomem_resource, &res[1]))
519 		panic("Request PCI Memory resource failed\n");
520 	sys->resource[1] = &res[1];
521 
522 	sys->resource[2] = NULL;
523 	sys->io_offset = 0;
524 
525 	return 1;
526 }
527 
528 
529 /*****************************************************************************
530  * General PCIe + PCI
531  ****************************************************************************/
532 static void __devinit rc_pci_fixup(struct pci_dev *dev)
533 {
534 	/*
535 	 * Prevent enumeration of root complex.
536 	 */
537 	if (dev->bus->parent == NULL && dev->devfn == 0) {
538 		int i;
539 
540 		for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
541 			dev->resource[i].start = 0;
542 			dev->resource[i].end   = 0;
543 			dev->resource[i].flags = 0;
544 		}
545 	}
546 }
547 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MARVELL, PCI_ANY_ID, rc_pci_fixup);
548 
549 static int orion5x_pci_disabled __initdata;
550 
551 void __init orion5x_pci_disable(void)
552 {
553 	orion5x_pci_disabled = 1;
554 }
555 
556 void __init orion5x_pci_set_cardbus_mode(void)
557 {
558 	orion5x_pci_cardbus_mode = 1;
559 }
560 
561 int __init orion5x_pci_sys_setup(int nr, struct pci_sys_data *sys)
562 {
563 	int ret = 0;
564 
565 	vga_base = ORION5X_PCIE_MEM_PHYS_BASE;
566 
567 	if (nr == 0) {
568 		orion_pcie_set_local_bus_nr(PCIE_BASE, sys->busnr);
569 		ret = pcie_setup(sys);
570 	} else if (nr == 1 && !orion5x_pci_disabled) {
571 		orion5x_pci_set_bus_nr(sys->busnr);
572 		ret = pci_setup(sys);
573 	}
574 
575 	return ret;
576 }
577 
578 struct pci_bus __init *orion5x_pci_sys_scan_bus(int nr, struct pci_sys_data *sys)
579 {
580 	struct pci_bus *bus;
581 
582 	if (nr == 0) {
583 		bus = pci_scan_bus(sys->busnr, &pcie_ops, sys);
584 	} else if (nr == 1 && !orion5x_pci_disabled) {
585 		bus = pci_scan_bus(sys->busnr, &pci_ops, sys);
586 	} else {
587 		bus = NULL;
588 		BUG();
589 	}
590 
591 	return bus;
592 }
593 
594 int __init orion5x_pci_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
595 {
596 	int bus = dev->bus->number;
597 
598 	/*
599 	 * PCIe endpoint?
600 	 */
601 	if (orion5x_pci_disabled || bus < orion5x_pci_local_bus_nr())
602 		return IRQ_ORION5X_PCIE0_INT;
603 
604 	return -1;
605 }
606