xref: /openbmc/linux/arch/arm/mach-orion5x/pci.c (revision 158c0c62)
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 "common.h"
22 
23 /*****************************************************************************
24  * Orion has one PCIe controller and one PCI controller.
25  *
26  * Note1: The local PCIe bus number is '0'. The local PCI bus number
27  * follows the scanned PCIe bridged busses, if any.
28  *
29  * Note2: It is possible for PCI/PCIe agents to access many subsystem's
30  * space, by configuring BARs and Address Decode Windows, e.g. flashes on
31  * device bus, Orion registers, etc. However this code only enable the
32  * access to DDR banks.
33  ****************************************************************************/
34 
35 
36 /*****************************************************************************
37  * PCIe controller
38  ****************************************************************************/
39 #define PCIE_BASE	((void __iomem *)ORION5X_PCIE_VIRT_BASE)
40 
41 void __init orion5x_pcie_id(u32 *dev, u32 *rev)
42 {
43 	*dev = orion_pcie_dev_id(PCIE_BASE);
44 	*rev = orion_pcie_rev(PCIE_BASE);
45 }
46 
47 static int pcie_valid_config(int bus, int dev)
48 {
49 	/*
50 	 * Don't go out when trying to access --
51 	 * 1. nonexisting device on local bus
52 	 * 2. where there's no device connected (no link)
53 	 */
54 	if (bus == 0 && dev == 0)
55 		return 1;
56 
57 	if (!orion_pcie_link_up(PCIE_BASE))
58 		return 0;
59 
60 	if (bus == 0 && dev != 1)
61 		return 0;
62 
63 	return 1;
64 }
65 
66 
67 /*
68  * PCIe config cycles are done by programming the PCIE_CONF_ADDR register
69  * and then reading the PCIE_CONF_DATA register. Need to make sure these
70  * transactions are atomic.
71  */
72 static DEFINE_SPINLOCK(orion5x_pcie_lock);
73 
74 static int pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
75 			int size, u32 *val)
76 {
77 	unsigned long flags;
78 	int ret;
79 
80 	if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0) {
81 		*val = 0xffffffff;
82 		return PCIBIOS_DEVICE_NOT_FOUND;
83 	}
84 
85 	spin_lock_irqsave(&orion5x_pcie_lock, flags);
86 	ret = orion_pcie_rd_conf(PCIE_BASE, bus, devfn, where, size, val);
87 	spin_unlock_irqrestore(&orion5x_pcie_lock, flags);
88 
89 	return ret;
90 }
91 
92 static int pcie_rd_conf_wa(struct pci_bus *bus, u32 devfn,
93 			   int where, int size, u32 *val)
94 {
95 	int ret;
96 
97 	if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0) {
98 		*val = 0xffffffff;
99 		return PCIBIOS_DEVICE_NOT_FOUND;
100 	}
101 
102 	/*
103 	 * We only support access to the non-extended configuration
104 	 * space when using the WA access method (or we would have to
105 	 * sacrifice 256M of CPU virtual address space.)
106 	 */
107 	if (where >= 0x100) {
108 		*val = 0xffffffff;
109 		return PCIBIOS_DEVICE_NOT_FOUND;
110 	}
111 
112 	ret = orion_pcie_rd_conf_wa((void __iomem *)ORION5X_PCIE_WA_VIRT_BASE,
113 				    bus, devfn, where, size, val);
114 
115 	return ret;
116 }
117 
118 static int pcie_wr_conf(struct pci_bus *bus, u32 devfn,
119 			int where, int size, u32 val)
120 {
121 	unsigned long flags;
122 	int ret;
123 
124 	if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0)
125 		return PCIBIOS_DEVICE_NOT_FOUND;
126 
127 	spin_lock_irqsave(&orion5x_pcie_lock, flags);
128 	ret = orion_pcie_wr_conf(PCIE_BASE, bus, devfn, where, size, val);
129 	spin_unlock_irqrestore(&orion5x_pcie_lock, flags);
130 
131 	return ret;
132 }
133 
134 static struct pci_ops pcie_ops = {
135 	.read = pcie_rd_conf,
136 	.write = pcie_wr_conf,
137 };
138 
139 
140 static int __init pcie_setup(struct pci_sys_data *sys)
141 {
142 	struct resource *res;
143 	int dev;
144 
145 	/*
146 	 * Generic PCIe unit setup.
147 	 */
148 	orion_pcie_setup(PCIE_BASE, &orion5x_mbus_dram_info);
149 
150 	/*
151 	 * Check whether to apply Orion-1/Orion-NAS PCIe config
152 	 * read transaction workaround.
153 	 */
154 	dev = orion_pcie_dev_id(PCIE_BASE);
155 	if (dev == MV88F5181_DEV_ID || dev == MV88F5182_DEV_ID) {
156 		printk(KERN_NOTICE "Applying Orion-1/Orion-NAS PCIe config "
157 				   "read transaction workaround\n");
158 		orion5x_setup_pcie_wa_win(ORION5X_PCIE_WA_PHYS_BASE,
159 					  ORION5X_PCIE_WA_SIZE);
160 		pcie_ops.read = pcie_rd_conf_wa;
161 	}
162 
163 	/*
164 	 * Request resources.
165 	 */
166 	res = kzalloc(sizeof(struct resource) * 2, GFP_KERNEL);
167 	if (!res)
168 		panic("pcie_setup unable to alloc resources");
169 
170 	/*
171 	 * IORESOURCE_IO
172 	 */
173 	res[0].name = "PCIe I/O Space";
174 	res[0].flags = IORESOURCE_IO;
175 	res[0].start = ORION5X_PCIE_IO_BUS_BASE;
176 	res[0].end = res[0].start + ORION5X_PCIE_IO_SIZE - 1;
177 	if (request_resource(&ioport_resource, &res[0]))
178 		panic("Request PCIe IO resource failed\n");
179 	sys->resource[0] = &res[0];
180 
181 	/*
182 	 * IORESOURCE_MEM
183 	 */
184 	res[1].name = "PCIe Memory Space";
185 	res[1].flags = IORESOURCE_MEM;
186 	res[1].start = ORION5X_PCIE_MEM_PHYS_BASE;
187 	res[1].end = res[1].start + ORION5X_PCIE_MEM_SIZE - 1;
188 	if (request_resource(&iomem_resource, &res[1]))
189 		panic("Request PCIe Memory resource failed\n");
190 	sys->resource[1] = &res[1];
191 
192 	sys->resource[2] = NULL;
193 	sys->io_offset = 0;
194 
195 	return 1;
196 }
197 
198 /*****************************************************************************
199  * PCI controller
200  ****************************************************************************/
201 #define ORION5X_PCI_REG(x)	(ORION5X_PCI_VIRT_BASE | (x))
202 #define PCI_MODE		ORION5X_PCI_REG(0xd00)
203 #define PCI_CMD			ORION5X_PCI_REG(0xc00)
204 #define PCI_P2P_CONF		ORION5X_PCI_REG(0x1d14)
205 #define PCI_CONF_ADDR		ORION5X_PCI_REG(0xc78)
206 #define PCI_CONF_DATA		ORION5X_PCI_REG(0xc7c)
207 
208 /*
209  * PCI_MODE bits
210  */
211 #define PCI_MODE_64BIT			(1 << 2)
212 #define PCI_MODE_PCIX			((1 << 4) | (1 << 5))
213 
214 /*
215  * PCI_CMD bits
216  */
217 #define PCI_CMD_HOST_REORDER		(1 << 29)
218 
219 /*
220  * PCI_P2P_CONF bits
221  */
222 #define PCI_P2P_BUS_OFFS		16
223 #define PCI_P2P_BUS_MASK		(0xff << PCI_P2P_BUS_OFFS)
224 #define PCI_P2P_DEV_OFFS		24
225 #define PCI_P2P_DEV_MASK		(0x1f << PCI_P2P_DEV_OFFS)
226 
227 /*
228  * PCI_CONF_ADDR bits
229  */
230 #define PCI_CONF_REG(reg)		((reg) & 0xfc)
231 #define PCI_CONF_FUNC(func)		(((func) & 0x3) << 8)
232 #define PCI_CONF_DEV(dev)		(((dev) & 0x1f) << 11)
233 #define PCI_CONF_BUS(bus)		(((bus) & 0xff) << 16)
234 #define PCI_CONF_ADDR_EN		(1 << 31)
235 
236 /*
237  * Internal configuration space
238  */
239 #define PCI_CONF_FUNC_STAT_CMD		0
240 #define PCI_CONF_REG_STAT_CMD		4
241 #define PCIX_STAT			0x64
242 #define PCIX_STAT_BUS_OFFS		8
243 #define PCIX_STAT_BUS_MASK		(0xff << PCIX_STAT_BUS_OFFS)
244 
245 /*
246  * PCI Address Decode Windows registers
247  */
248 #define PCI_BAR_SIZE_DDR_CS(n)	(((n) == 0) ? ORION5X_PCI_REG(0xc08) : \
249 				 ((n) == 1) ? ORION5X_PCI_REG(0xd08) : \
250 				 ((n) == 2) ? ORION5X_PCI_REG(0xc0c) : \
251 				 ((n) == 3) ? ORION5X_PCI_REG(0xd0c) : 0)
252 #define PCI_BAR_REMAP_DDR_CS(n)	(((n) == 0) ? ORION5X_PCI_REG(0xc48) : \
253 				 ((n) == 1) ? ORION5X_PCI_REG(0xd48) : \
254 				 ((n) == 2) ? ORION5X_PCI_REG(0xc4c) : \
255 				 ((n) == 3) ? ORION5X_PCI_REG(0xd4c) : 0)
256 #define PCI_BAR_ENABLE		ORION5X_PCI_REG(0xc3c)
257 #define PCI_ADDR_DECODE_CTRL	ORION5X_PCI_REG(0xd3c)
258 
259 /*
260  * PCI configuration helpers for BAR settings
261  */
262 #define PCI_CONF_FUNC_BAR_CS(n)		((n) >> 1)
263 #define PCI_CONF_REG_BAR_LO_CS(n)	(((n) & 1) ? 0x18 : 0x10)
264 #define PCI_CONF_REG_BAR_HI_CS(n)	(((n) & 1) ? 0x1c : 0x14)
265 
266 /*
267  * PCI config cycles are done by programming the PCI_CONF_ADDR register
268  * and then reading the PCI_CONF_DATA register. Need to make sure these
269  * transactions are atomic.
270  */
271 static DEFINE_SPINLOCK(orion5x_pci_lock);
272 
273 static int orion5x_pci_cardbus_mode;
274 
275 static int orion5x_pci_local_bus_nr(void)
276 {
277 	u32 conf = readl(PCI_P2P_CONF);
278 	return((conf & PCI_P2P_BUS_MASK) >> PCI_P2P_BUS_OFFS);
279 }
280 
281 static int orion5x_pci_hw_rd_conf(int bus, int dev, u32 func,
282 					u32 where, u32 size, u32 *val)
283 {
284 	unsigned long flags;
285 	spin_lock_irqsave(&orion5x_pci_lock, flags);
286 
287 	writel(PCI_CONF_BUS(bus) |
288 		PCI_CONF_DEV(dev) | PCI_CONF_REG(where) |
289 		PCI_CONF_FUNC(func) | PCI_CONF_ADDR_EN, PCI_CONF_ADDR);
290 
291 	*val = readl(PCI_CONF_DATA);
292 
293 	if (size == 1)
294 		*val = (*val >> (8*(where & 0x3))) & 0xff;
295 	else if (size == 2)
296 		*val = (*val >> (8*(where & 0x3))) & 0xffff;
297 
298 	spin_unlock_irqrestore(&orion5x_pci_lock, flags);
299 
300 	return PCIBIOS_SUCCESSFUL;
301 }
302 
303 static int orion5x_pci_hw_wr_conf(int bus, int dev, u32 func,
304 					u32 where, u32 size, u32 val)
305 {
306 	unsigned long flags;
307 	int ret = PCIBIOS_SUCCESSFUL;
308 
309 	spin_lock_irqsave(&orion5x_pci_lock, flags);
310 
311 	writel(PCI_CONF_BUS(bus) |
312 		PCI_CONF_DEV(dev) | PCI_CONF_REG(where) |
313 		PCI_CONF_FUNC(func) | PCI_CONF_ADDR_EN, PCI_CONF_ADDR);
314 
315 	if (size == 4) {
316 		__raw_writel(val, PCI_CONF_DATA);
317 	} else if (size == 2) {
318 		__raw_writew(val, PCI_CONF_DATA + (where & 0x3));
319 	} else if (size == 1) {
320 		__raw_writeb(val, PCI_CONF_DATA + (where & 0x3));
321 	} else {
322 		ret = PCIBIOS_BAD_REGISTER_NUMBER;
323 	}
324 
325 	spin_unlock_irqrestore(&orion5x_pci_lock, flags);
326 
327 	return ret;
328 }
329 
330 static int orion5x_pci_valid_config(int bus, u32 devfn)
331 {
332 	if (bus == orion5x_pci_local_bus_nr()) {
333 		/*
334 		 * Don't go out for local device
335 		 */
336 		if (PCI_SLOT(devfn) == 0 && PCI_FUNC(devfn) != 0)
337 			return 0;
338 
339 		/*
340 		 * When the PCI signals are directly connected to a
341 		 * Cardbus slot, ignore all but device IDs 0 and 1.
342 		 */
343 		if (orion5x_pci_cardbus_mode && PCI_SLOT(devfn) > 1)
344 			return 0;
345 	}
346 
347 	return 1;
348 }
349 
350 static int orion5x_pci_rd_conf(struct pci_bus *bus, u32 devfn,
351 				int where, int size, u32 *val)
352 {
353 	if (!orion5x_pci_valid_config(bus->number, devfn)) {
354 		*val = 0xffffffff;
355 		return PCIBIOS_DEVICE_NOT_FOUND;
356 	}
357 
358 	return orion5x_pci_hw_rd_conf(bus->number, PCI_SLOT(devfn),
359 					PCI_FUNC(devfn), where, size, val);
360 }
361 
362 static int orion5x_pci_wr_conf(struct pci_bus *bus, u32 devfn,
363 				int where, int size, u32 val)
364 {
365 	if (!orion5x_pci_valid_config(bus->number, devfn))
366 		return PCIBIOS_DEVICE_NOT_FOUND;
367 
368 	return orion5x_pci_hw_wr_conf(bus->number, PCI_SLOT(devfn),
369 					PCI_FUNC(devfn), where, size, val);
370 }
371 
372 static struct pci_ops pci_ops = {
373 	.read = orion5x_pci_rd_conf,
374 	.write = orion5x_pci_wr_conf,
375 };
376 
377 static void __init orion5x_pci_set_bus_nr(int nr)
378 {
379 	u32 p2p = readl(PCI_P2P_CONF);
380 
381 	if (readl(PCI_MODE) & PCI_MODE_PCIX) {
382 		/*
383 		 * PCI-X mode
384 		 */
385 		u32 pcix_status, bus, dev;
386 		bus = (p2p & PCI_P2P_BUS_MASK) >> PCI_P2P_BUS_OFFS;
387 		dev = (p2p & PCI_P2P_DEV_MASK) >> PCI_P2P_DEV_OFFS;
388 		orion5x_pci_hw_rd_conf(bus, dev, 0, PCIX_STAT, 4, &pcix_status);
389 		pcix_status &= ~PCIX_STAT_BUS_MASK;
390 		pcix_status |= (nr << PCIX_STAT_BUS_OFFS);
391 		orion5x_pci_hw_wr_conf(bus, dev, 0, PCIX_STAT, 4, pcix_status);
392 	} else {
393 		/*
394 		 * PCI Conventional mode
395 		 */
396 		p2p &= ~PCI_P2P_BUS_MASK;
397 		p2p |= (nr << PCI_P2P_BUS_OFFS);
398 		writel(p2p, PCI_P2P_CONF);
399 	}
400 }
401 
402 static void __init orion5x_pci_master_slave_enable(void)
403 {
404 	int bus_nr, func, reg;
405 	u32 val;
406 
407 	bus_nr = orion5x_pci_local_bus_nr();
408 	func = PCI_CONF_FUNC_STAT_CMD;
409 	reg = PCI_CONF_REG_STAT_CMD;
410 	orion5x_pci_hw_rd_conf(bus_nr, 0, func, reg, 4, &val);
411 	val |= (PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
412 	orion5x_pci_hw_wr_conf(bus_nr, 0, func, reg, 4, val | 0x7);
413 }
414 
415 static void __init orion5x_setup_pci_wins(struct mbus_dram_target_info *dram)
416 {
417 	u32 win_enable;
418 	int bus;
419 	int i;
420 
421 	/*
422 	 * First, disable windows.
423 	 */
424 	win_enable = 0xffffffff;
425 	writel(win_enable, PCI_BAR_ENABLE);
426 
427 	/*
428 	 * Setup windows for DDR banks.
429 	 */
430 	bus = orion5x_pci_local_bus_nr();
431 
432 	for (i = 0; i < dram->num_cs; i++) {
433 		struct mbus_dram_window *cs = dram->cs + i;
434 		u32 func = PCI_CONF_FUNC_BAR_CS(cs->cs_index);
435 		u32 reg;
436 		u32 val;
437 
438 		/*
439 		 * Write DRAM bank base address register.
440 		 */
441 		reg = PCI_CONF_REG_BAR_LO_CS(cs->cs_index);
442 		orion5x_pci_hw_rd_conf(bus, 0, func, reg, 4, &val);
443 		val = (cs->base & 0xfffff000) | (val & 0xfff);
444 		orion5x_pci_hw_wr_conf(bus, 0, func, reg, 4, val);
445 
446 		/*
447 		 * Write DRAM bank size register.
448 		 */
449 		reg = PCI_CONF_REG_BAR_HI_CS(cs->cs_index);
450 		orion5x_pci_hw_wr_conf(bus, 0, func, reg, 4, 0);
451 		writel((cs->size - 1) & 0xfffff000,
452 			PCI_BAR_SIZE_DDR_CS(cs->cs_index));
453 		writel(cs->base & 0xfffff000,
454 			PCI_BAR_REMAP_DDR_CS(cs->cs_index));
455 
456 		/*
457 		 * Enable decode window for this chip select.
458 		 */
459 		win_enable &= ~(1 << cs->cs_index);
460 	}
461 
462 	/*
463 	 * Re-enable decode windows.
464 	 */
465 	writel(win_enable, PCI_BAR_ENABLE);
466 
467 	/*
468 	 * Disable automatic update of address remapping when writing to BARs.
469 	 */
470 	orion5x_setbits(PCI_ADDR_DECODE_CTRL, 1);
471 }
472 
473 static int __init pci_setup(struct pci_sys_data *sys)
474 {
475 	struct resource *res;
476 
477 	/*
478 	 * Point PCI unit MBUS decode windows to DRAM space.
479 	 */
480 	orion5x_setup_pci_wins(&orion5x_mbus_dram_info);
481 
482 	/*
483 	 * Master + Slave enable
484 	 */
485 	orion5x_pci_master_slave_enable();
486 
487 	/*
488 	 * Force ordering
489 	 */
490 	orion5x_setbits(PCI_CMD, PCI_CMD_HOST_REORDER);
491 
492 	/*
493 	 * Request resources
494 	 */
495 	res = kzalloc(sizeof(struct resource) * 2, GFP_KERNEL);
496 	if (!res)
497 		panic("pci_setup unable to alloc resources");
498 
499 	/*
500 	 * IORESOURCE_IO
501 	 */
502 	res[0].name = "PCI I/O Space";
503 	res[0].flags = IORESOURCE_IO;
504 	res[0].start = ORION5X_PCI_IO_BUS_BASE;
505 	res[0].end = res[0].start + ORION5X_PCI_IO_SIZE - 1;
506 	if (request_resource(&ioport_resource, &res[0]))
507 		panic("Request PCI IO resource failed\n");
508 	sys->resource[0] = &res[0];
509 
510 	/*
511 	 * IORESOURCE_MEM
512 	 */
513 	res[1].name = "PCI Memory Space";
514 	res[1].flags = IORESOURCE_MEM;
515 	res[1].start = ORION5X_PCI_MEM_PHYS_BASE;
516 	res[1].end = res[1].start + ORION5X_PCI_MEM_SIZE - 1;
517 	if (request_resource(&iomem_resource, &res[1]))
518 		panic("Request PCI Memory resource failed\n");
519 	sys->resource[1] = &res[1];
520 
521 	sys->resource[2] = NULL;
522 	sys->io_offset = 0;
523 
524 	return 1;
525 }
526 
527 
528 /*****************************************************************************
529  * General PCIe + PCI
530  ****************************************************************************/
531 static void __devinit rc_pci_fixup(struct pci_dev *dev)
532 {
533 	/*
534 	 * Prevent enumeration of root complex.
535 	 */
536 	if (dev->bus->parent == NULL && dev->devfn == 0) {
537 		int i;
538 
539 		for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
540 			dev->resource[i].start = 0;
541 			dev->resource[i].end   = 0;
542 			dev->resource[i].flags = 0;
543 		}
544 	}
545 }
546 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MARVELL, PCI_ANY_ID, rc_pci_fixup);
547 
548 static int orion5x_pci_disabled __initdata;
549 
550 void __init orion5x_pci_disable(void)
551 {
552 	orion5x_pci_disabled = 1;
553 }
554 
555 void __init orion5x_pci_set_cardbus_mode(void)
556 {
557 	orion5x_pci_cardbus_mode = 1;
558 }
559 
560 int __init orion5x_pci_sys_setup(int nr, struct pci_sys_data *sys)
561 {
562 	int ret = 0;
563 
564 	vga_base = ORION5X_PCIE_MEM_PHYS_BASE;
565 
566 	if (nr == 0) {
567 		orion_pcie_set_local_bus_nr(PCIE_BASE, sys->busnr);
568 		ret = pcie_setup(sys);
569 	} else if (nr == 1 && !orion5x_pci_disabled) {
570 		orion5x_pci_set_bus_nr(sys->busnr);
571 		ret = pci_setup(sys);
572 	}
573 
574 	return ret;
575 }
576 
577 struct pci_bus __init *orion5x_pci_sys_scan_bus(int nr, struct pci_sys_data *sys)
578 {
579 	struct pci_bus *bus;
580 
581 	if (nr == 0) {
582 		bus = pci_scan_bus(sys->busnr, &pcie_ops, sys);
583 	} else if (nr == 1 && !orion5x_pci_disabled) {
584 		bus = pci_scan_bus(sys->busnr, &pci_ops, sys);
585 	} else {
586 		bus = NULL;
587 		BUG();
588 	}
589 
590 	return bus;
591 }
592 
593 int __init orion5x_pci_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
594 {
595 	int bus = dev->bus->number;
596 
597 	/*
598 	 * PCIe endpoint?
599 	 */
600 	if (orion5x_pci_disabled || bus < orion5x_pci_local_bus_nr())
601 		return IRQ_ORION5X_PCIE0_INT;
602 
603 	return -1;
604 }
605