xref: /openbmc/linux/arch/arm/mach-orion5x/pci.c (revision 9dd0b194)
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/mbus.h>
16 #include <asm/mach/pci.h>
17 #include <asm/plat-orion/pcie.h>
18 #include "common.h"
19 
20 /*****************************************************************************
21  * Orion has one PCIe controller and one PCI controller.
22  *
23  * Note1: The local PCIe bus number is '0'. The local PCI bus number
24  * follows the scanned PCIe bridged busses, if any.
25  *
26  * Note2: It is possible for PCI/PCIe agents to access many subsystem's
27  * space, by configuring BARs and Address Decode Windows, e.g. flashes on
28  * device bus, Orion registers, etc. However this code only enable the
29  * access to DDR banks.
30  ****************************************************************************/
31 
32 
33 /*****************************************************************************
34  * PCIe controller
35  ****************************************************************************/
36 #define PCIE_BASE	((void __iomem *)ORION5X_PCIE_VIRT_BASE)
37 
38 void __init orion5x_pcie_id(u32 *dev, u32 *rev)
39 {
40 	*dev = orion_pcie_dev_id(PCIE_BASE);
41 	*rev = orion_pcie_rev(PCIE_BASE);
42 }
43 
44 int orion5x_pcie_local_bus_nr(void)
45 {
46 	return orion_pcie_get_local_bus_nr(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((void __iomem *)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, &orion5x_mbus_dram_info);
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 		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 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 int orion5x_pci_local_bus_nr(void)
273 {
274 	u32 conf = orion5x_read(PCI_P2P_CONF);
275 	return((conf & PCI_P2P_BUS_MASK) >> PCI_P2P_BUS_OFFS);
276 }
277 
278 static int orion5x_pci_hw_rd_conf(int bus, int dev, u32 func,
279 					u32 where, u32 size, u32 *val)
280 {
281 	unsigned long flags;
282 	spin_lock_irqsave(&orion5x_pci_lock, flags);
283 
284 	orion5x_write(PCI_CONF_ADDR, PCI_CONF_BUS(bus) |
285 			PCI_CONF_DEV(dev) | PCI_CONF_REG(where) |
286 			PCI_CONF_FUNC(func) | PCI_CONF_ADDR_EN);
287 
288 	*val = orion5x_read(PCI_CONF_DATA);
289 
290 	if (size == 1)
291 		*val = (*val >> (8*(where & 0x3))) & 0xff;
292 	else if (size == 2)
293 		*val = (*val >> (8*(where & 0x3))) & 0xffff;
294 
295 	spin_unlock_irqrestore(&orion5x_pci_lock, flags);
296 
297 	return PCIBIOS_SUCCESSFUL;
298 }
299 
300 static int orion5x_pci_hw_wr_conf(int bus, int dev, u32 func,
301 					u32 where, u32 size, u32 val)
302 {
303 	unsigned long flags;
304 	int ret = PCIBIOS_SUCCESSFUL;
305 
306 	spin_lock_irqsave(&orion5x_pci_lock, flags);
307 
308 	orion5x_write(PCI_CONF_ADDR, PCI_CONF_BUS(bus) |
309 			PCI_CONF_DEV(dev) | PCI_CONF_REG(where) |
310 			PCI_CONF_FUNC(func) | PCI_CONF_ADDR_EN);
311 
312 	if (size == 4) {
313 		__raw_writel(val, PCI_CONF_DATA);
314 	} else if (size == 2) {
315 		__raw_writew(val, PCI_CONF_DATA + (where & 0x3));
316 	} else if (size == 1) {
317 		__raw_writeb(val, PCI_CONF_DATA + (where & 0x3));
318 	} else {
319 		ret = PCIBIOS_BAD_REGISTER_NUMBER;
320 	}
321 
322 	spin_unlock_irqrestore(&orion5x_pci_lock, flags);
323 
324 	return ret;
325 }
326 
327 static int orion5x_pci_rd_conf(struct pci_bus *bus, u32 devfn,
328 				int where, int size, u32 *val)
329 {
330 	/*
331 	 * Don't go out for local device
332 	 */
333 	if (bus->number == orion5x_pci_local_bus_nr() &&
334 	    PCI_SLOT(devfn) == 0 && PCI_FUNC(devfn) != 0) {
335 		*val = 0xffffffff;
336 		return PCIBIOS_DEVICE_NOT_FOUND;
337 	}
338 
339 	return orion5x_pci_hw_rd_conf(bus->number, PCI_SLOT(devfn),
340 					PCI_FUNC(devfn), where, size, val);
341 }
342 
343 static int orion5x_pci_wr_conf(struct pci_bus *bus, u32 devfn,
344 				int where, int size, u32 val)
345 {
346 	if (bus->number == orion5x_pci_local_bus_nr() &&
347 	    PCI_SLOT(devfn) == 0 && PCI_FUNC(devfn) != 0)
348 		return PCIBIOS_DEVICE_NOT_FOUND;
349 
350 	return orion5x_pci_hw_wr_conf(bus->number, PCI_SLOT(devfn),
351 					PCI_FUNC(devfn), where, size, val);
352 }
353 
354 static struct pci_ops pci_ops = {
355 	.read = orion5x_pci_rd_conf,
356 	.write = orion5x_pci_wr_conf,
357 };
358 
359 static void __init orion5x_pci_set_bus_nr(int nr)
360 {
361 	u32 p2p = orion5x_read(PCI_P2P_CONF);
362 
363 	if (orion5x_read(PCI_MODE) & PCI_MODE_PCIX) {
364 		/*
365 		 * PCI-X mode
366 		 */
367 		u32 pcix_status, bus, dev;
368 		bus = (p2p & PCI_P2P_BUS_MASK) >> PCI_P2P_BUS_OFFS;
369 		dev = (p2p & PCI_P2P_DEV_MASK) >> PCI_P2P_DEV_OFFS;
370 		orion5x_pci_hw_rd_conf(bus, dev, 0, PCIX_STAT, 4, &pcix_status);
371 		pcix_status &= ~PCIX_STAT_BUS_MASK;
372 		pcix_status |= (nr << PCIX_STAT_BUS_OFFS);
373 		orion5x_pci_hw_wr_conf(bus, dev, 0, PCIX_STAT, 4, pcix_status);
374 	} else {
375 		/*
376 		 * PCI Conventional mode
377 		 */
378 		p2p &= ~PCI_P2P_BUS_MASK;
379 		p2p |= (nr << PCI_P2P_BUS_OFFS);
380 		orion5x_write(PCI_P2P_CONF, p2p);
381 	}
382 }
383 
384 static void __init orion5x_pci_master_slave_enable(void)
385 {
386 	int bus_nr, func, reg;
387 	u32 val;
388 
389 	bus_nr = orion5x_pci_local_bus_nr();
390 	func = PCI_CONF_FUNC_STAT_CMD;
391 	reg = PCI_CONF_REG_STAT_CMD;
392 	orion5x_pci_hw_rd_conf(bus_nr, 0, func, reg, 4, &val);
393 	val |= (PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
394 	orion5x_pci_hw_wr_conf(bus_nr, 0, func, reg, 4, val | 0x7);
395 }
396 
397 static void __init orion5x_setup_pci_wins(struct mbus_dram_target_info *dram)
398 {
399 	u32 win_enable;
400 	int bus;
401 	int i;
402 
403 	/*
404 	 * First, disable windows.
405 	 */
406 	win_enable = 0xffffffff;
407 	orion5x_write(PCI_BAR_ENABLE, win_enable);
408 
409 	/*
410 	 * Setup windows for DDR banks.
411 	 */
412 	bus = orion5x_pci_local_bus_nr();
413 
414 	for (i = 0; i < dram->num_cs; i++) {
415 		struct mbus_dram_window *cs = dram->cs + i;
416 		u32 func = PCI_CONF_FUNC_BAR_CS(cs->cs_index);
417 		u32 reg;
418 		u32 val;
419 
420 		/*
421 		 * Write DRAM bank base address register.
422 		 */
423 		reg = PCI_CONF_REG_BAR_LO_CS(cs->cs_index);
424 		orion5x_pci_hw_rd_conf(bus, 0, func, reg, 4, &val);
425 		val = (cs->base & 0xfffff000) | (val & 0xfff);
426 		orion5x_pci_hw_wr_conf(bus, 0, func, reg, 4, val);
427 
428 		/*
429 		 * Write DRAM bank size register.
430 		 */
431 		reg = PCI_CONF_REG_BAR_HI_CS(cs->cs_index);
432 		orion5x_pci_hw_wr_conf(bus, 0, func, reg, 4, 0);
433 		orion5x_write(PCI_BAR_SIZE_DDR_CS(cs->cs_index),
434 				(cs->size - 1) & 0xfffff000);
435 		orion5x_write(PCI_BAR_REMAP_DDR_CS(cs->cs_index),
436 				cs->base & 0xfffff000);
437 
438 		/*
439 		 * Enable decode window for this chip select.
440 		 */
441 		win_enable &= ~(1 << cs->cs_index);
442 	}
443 
444 	/*
445 	 * Re-enable decode windows.
446 	 */
447 	orion5x_write(PCI_BAR_ENABLE, win_enable);
448 
449 	/*
450 	 * Disable automatic update of address remaping when writing to BARs.
451 	 */
452 	orion5x_setbits(PCI_ADDR_DECODE_CTRL, 1);
453 }
454 
455 static int __init pci_setup(struct pci_sys_data *sys)
456 {
457 	struct resource *res;
458 
459 	/*
460 	 * Point PCI unit MBUS decode windows to DRAM space.
461 	 */
462 	orion5x_setup_pci_wins(&orion5x_mbus_dram_info);
463 
464 	/*
465 	 * Master + Slave enable
466 	 */
467 	orion5x_pci_master_slave_enable();
468 
469 	/*
470 	 * Force ordering
471 	 */
472 	orion5x_setbits(PCI_CMD, PCI_CMD_HOST_REORDER);
473 
474 	/*
475 	 * Request resources
476 	 */
477 	res = kzalloc(sizeof(struct resource) * 2, GFP_KERNEL);
478 	if (!res)
479 		panic("pci_setup unable to alloc resources");
480 
481 	/*
482 	 * IORESOURCE_IO
483 	 */
484 	res[0].name = "PCI I/O Space";
485 	res[0].flags = IORESOURCE_IO;
486 	res[0].start = ORION5X_PCI_IO_BUS_BASE;
487 	res[0].end = res[0].start + ORION5X_PCI_IO_SIZE - 1;
488 	if (request_resource(&ioport_resource, &res[0]))
489 		panic("Request PCI IO resource failed\n");
490 	sys->resource[0] = &res[0];
491 
492 	/*
493 	 * IORESOURCE_MEM
494 	 */
495 	res[1].name = "PCI Memory Space";
496 	res[1].flags = IORESOURCE_MEM;
497 	res[1].start = ORION5X_PCI_MEM_PHYS_BASE;
498 	res[1].end = res[1].start + ORION5X_PCI_MEM_SIZE - 1;
499 	if (request_resource(&iomem_resource, &res[1]))
500 		panic("Request PCI Memory resource failed\n");
501 	sys->resource[1] = &res[1];
502 
503 	sys->resource[2] = NULL;
504 	sys->io_offset = 0;
505 
506 	return 1;
507 }
508 
509 
510 /*****************************************************************************
511  * General PCIe + PCI
512  ****************************************************************************/
513 static void __devinit 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 int __init orion5x_pci_sys_setup(int nr, struct pci_sys_data *sys)
531 {
532 	int ret = 0;
533 
534 	if (nr == 0) {
535 		orion_pcie_set_local_bus_nr(PCIE_BASE, sys->busnr);
536 		ret = pcie_setup(sys);
537 	} else if (nr == 1) {
538 		orion5x_pci_set_bus_nr(sys->busnr);
539 		ret = pci_setup(sys);
540 	}
541 
542 	return ret;
543 }
544 
545 struct pci_bus __init *orion5x_pci_sys_scan_bus(int nr, struct pci_sys_data *sys)
546 {
547 	struct pci_bus *bus;
548 
549 	if (nr == 0) {
550 		bus = pci_scan_bus(sys->busnr, &pcie_ops, sys);
551 	} else if (nr == 1) {
552 		bus = pci_scan_bus(sys->busnr, &pci_ops, sys);
553 	} else {
554 		bus = NULL;
555 		BUG();
556 	}
557 
558 	return bus;
559 }
560