xref: /linux/arch/sh/drivers/pci/pcie-sh7786.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
1 /*
2  * Low-Level PCI Express Support for the SH7786
3  *
4  *  Copyright (C) 2009 - 2011  Paul Mundt
5  *
6  * This file is subject to the terms and conditions of the GNU General Public
7  * License.  See the file "COPYING" in the main directory of this archive
8  * for more details.
9  */
10 #define pr_fmt(fmt) "PCI: " fmt
11 
12 #include <linux/pci.h>
13 #include <linux/init.h>
14 #include <linux/kernel.h>
15 #include <linux/io.h>
16 #include <linux/async.h>
17 #include <linux/delay.h>
18 #include <linux/slab.h>
19 #include <linux/clk.h>
20 #include <linux/sh_clk.h>
21 #include <linux/sh_intc.h>
22 #include "pcie-sh7786.h"
23 #include <asm/sizes.h>
24 
25 struct sh7786_pcie_port {
26 	struct pci_channel	*hose;
27 	struct clk		*fclk, phy_clk;
28 	unsigned int		index;
29 	int			endpoint;
30 	int			link;
31 };
32 
33 static struct sh7786_pcie_port *sh7786_pcie_ports;
34 static unsigned int nr_ports;
35 
36 static struct sh7786_pcie_hwops {
37 	int (*core_init)(void);
38 	async_func_ptr *port_init_hw;
39 } *sh7786_pcie_hwops;
40 
41 static struct resource sh7786_pci0_resources[] = {
42 	{
43 		.name	= "PCIe0 IO",
44 		.start	= 0xfd000000,
45 		.end	= 0xfd000000 + SZ_8M - 1,
46 		.flags	= IORESOURCE_IO,
47 	}, {
48 		.name	= "PCIe0 MEM 0",
49 		.start	= 0xc0000000,
50 		.end	= 0xc0000000 + SZ_512M - 1,
51 		.flags	= IORESOURCE_MEM | IORESOURCE_MEM_32BIT,
52 	}, {
53 		.name	= "PCIe0 MEM 1",
54 		.start	= 0x10000000,
55 		.end	= 0x10000000 + SZ_64M - 1,
56 		.flags	= IORESOURCE_MEM,
57 	}, {
58 		.name	= "PCIe0 MEM 2",
59 		.start	= 0xfe100000,
60 		.end	= 0xfe100000 + SZ_1M - 1,
61 		.flags	= IORESOURCE_MEM,
62 	},
63 };
64 
65 static struct resource sh7786_pci1_resources[] = {
66 	{
67 		.name	= "PCIe1 IO",
68 		.start	= 0xfd800000,
69 		.end	= 0xfd800000 + SZ_8M - 1,
70 		.flags	= IORESOURCE_IO,
71 	}, {
72 		.name	= "PCIe1 MEM 0",
73 		.start	= 0xa0000000,
74 		.end	= 0xa0000000 + SZ_512M - 1,
75 		.flags	= IORESOURCE_MEM | IORESOURCE_MEM_32BIT,
76 	}, {
77 		.name	= "PCIe1 MEM 1",
78 		.start	= 0x30000000,
79 		.end	= 0x30000000 + SZ_256M - 1,
80 		.flags	= IORESOURCE_MEM | IORESOURCE_MEM_32BIT,
81 	}, {
82 		.name	= "PCIe1 MEM 2",
83 		.start	= 0xfe300000,
84 		.end	= 0xfe300000 + SZ_1M - 1,
85 		.flags	= IORESOURCE_MEM,
86 	},
87 };
88 
89 static struct resource sh7786_pci2_resources[] = {
90 	{
91 		.name	= "PCIe2 IO",
92 		.start	= 0xfc800000,
93 		.end	= 0xfc800000 + SZ_4M - 1,
94 		.flags	= IORESOURCE_IO,
95 	}, {
96 		.name	= "PCIe2 MEM 0",
97 		.start	= 0x80000000,
98 		.end	= 0x80000000 + SZ_512M - 1,
99 		.flags	= IORESOURCE_MEM | IORESOURCE_MEM_32BIT,
100 	}, {
101 		.name	= "PCIe2 MEM 1",
102 		.start	= 0x20000000,
103 		.end	= 0x20000000 + SZ_256M - 1,
104 		.flags	= IORESOURCE_MEM | IORESOURCE_MEM_32BIT,
105 	}, {
106 		.name	= "PCIe2 MEM 2",
107 		.start	= 0xfcd00000,
108 		.end	= 0xfcd00000 + SZ_1M - 1,
109 		.flags	= IORESOURCE_MEM,
110 	},
111 };
112 
113 extern struct pci_ops sh7786_pci_ops;
114 
115 #define DEFINE_CONTROLLER(start, idx)					\
116 {									\
117 	.pci_ops	= &sh7786_pci_ops,				\
118 	.resources	= sh7786_pci##idx##_resources,			\
119 	.nr_resources	= ARRAY_SIZE(sh7786_pci##idx##_resources),	\
120 	.reg_base	= start,					\
121 	.mem_offset	= 0,						\
122 	.io_offset	= 0,						\
123 }
124 
125 static struct pci_channel sh7786_pci_channels[] = {
126 	DEFINE_CONTROLLER(0xfe000000, 0),
127 	DEFINE_CONTROLLER(0xfe200000, 1),
128 	DEFINE_CONTROLLER(0xfcc00000, 2),
129 };
130 
131 static struct clk fixed_pciexclkp = {
132 	.rate = 100000000,	/* 100 MHz reference clock */
133 };
134 
135 static void __devinit sh7786_pci_fixup(struct pci_dev *dev)
136 {
137 	/*
138 	 * Prevent enumeration of root complex resources.
139 	 */
140 	if (pci_is_root_bus(dev->bus) && dev->devfn == 0) {
141 		int i;
142 
143 		for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
144 			dev->resource[i].start	= 0;
145 			dev->resource[i].end	= 0;
146 			dev->resource[i].flags	= 0;
147 		}
148 	}
149 }
150 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_RENESAS, PCI_DEVICE_ID_RENESAS_SH7786,
151 			 sh7786_pci_fixup);
152 
153 static int __init phy_wait_for_ack(struct pci_channel *chan)
154 {
155 	unsigned int timeout = 100;
156 
157 	while (timeout--) {
158 		if (pci_read_reg(chan, SH4A_PCIEPHYADRR) & (1 << BITS_ACK))
159 			return 0;
160 
161 		udelay(100);
162 	}
163 
164 	return -ETIMEDOUT;
165 }
166 
167 static int __init pci_wait_for_irq(struct pci_channel *chan, unsigned int mask)
168 {
169 	unsigned int timeout = 100;
170 
171 	while (timeout--) {
172 		if ((pci_read_reg(chan, SH4A_PCIEINTR) & mask) == mask)
173 			return 0;
174 
175 		udelay(100);
176 	}
177 
178 	return -ETIMEDOUT;
179 }
180 
181 static void __init phy_write_reg(struct pci_channel *chan, unsigned int addr,
182 				 unsigned int lane, unsigned int data)
183 {
184 	unsigned long phyaddr;
185 
186 	phyaddr = (1 << BITS_CMD) + ((lane & 0xf) << BITS_LANE) +
187 			((addr & 0xff) << BITS_ADR);
188 
189 	/* Set write data */
190 	pci_write_reg(chan, data, SH4A_PCIEPHYDOUTR);
191 	pci_write_reg(chan, phyaddr, SH4A_PCIEPHYADRR);
192 
193 	phy_wait_for_ack(chan);
194 
195 	/* Clear command */
196 	pci_write_reg(chan, 0, SH4A_PCIEPHYDOUTR);
197 	pci_write_reg(chan, 0, SH4A_PCIEPHYADRR);
198 
199 	phy_wait_for_ack(chan);
200 }
201 
202 static int __init pcie_clk_init(struct sh7786_pcie_port *port)
203 {
204 	struct pci_channel *chan = port->hose;
205 	struct clk *clk;
206 	char fclk_name[16];
207 	int ret;
208 
209 	/*
210 	 * First register the fixed clock
211 	 */
212 	ret = clk_register(&fixed_pciexclkp);
213 	if (unlikely(ret != 0))
214 		return ret;
215 
216 	/*
217 	 * Grab the port's function clock, which the PHY clock depends
218 	 * on. clock lookups don't help us much at this point, since no
219 	 * dev_id is available this early. Lame.
220 	 */
221 	snprintf(fclk_name, sizeof(fclk_name), "pcie%d_fck", port->index);
222 
223 	port->fclk = clk_get(NULL, fclk_name);
224 	if (IS_ERR(port->fclk)) {
225 		ret = PTR_ERR(port->fclk);
226 		goto err_fclk;
227 	}
228 
229 	clk_enable(port->fclk);
230 
231 	/*
232 	 * And now, set up the PHY clock
233 	 */
234 	clk = &port->phy_clk;
235 
236 	memset(clk, 0, sizeof(struct clk));
237 
238 	clk->parent = &fixed_pciexclkp;
239 	clk->enable_reg = (void __iomem *)(chan->reg_base + SH4A_PCIEPHYCTLR);
240 	clk->enable_bit = BITS_CKE;
241 
242 	ret = sh_clk_mstp_register(clk, 1);
243 	if (unlikely(ret < 0))
244 		goto err_phy;
245 
246 	return 0;
247 
248 err_phy:
249 	clk_disable(port->fclk);
250 	clk_put(port->fclk);
251 err_fclk:
252 	clk_unregister(&fixed_pciexclkp);
253 
254 	return ret;
255 }
256 
257 static int __init phy_init(struct sh7786_pcie_port *port)
258 {
259 	struct pci_channel *chan = port->hose;
260 	unsigned int timeout = 100;
261 
262 	clk_enable(&port->phy_clk);
263 
264 	/* Initialize the phy */
265 	phy_write_reg(chan, 0x60, 0xf, 0x004b008b);
266 	phy_write_reg(chan, 0x61, 0xf, 0x00007b41);
267 	phy_write_reg(chan, 0x64, 0xf, 0x00ff4f00);
268 	phy_write_reg(chan, 0x65, 0xf, 0x09070907);
269 	phy_write_reg(chan, 0x66, 0xf, 0x00000010);
270 	phy_write_reg(chan, 0x74, 0xf, 0x0007001c);
271 	phy_write_reg(chan, 0x79, 0xf, 0x01fc000d);
272 	phy_write_reg(chan, 0xb0, 0xf, 0x00000610);
273 
274 	/* Deassert Standby */
275 	phy_write_reg(chan, 0x67, 0x1, 0x00000400);
276 
277 	/* Disable clock */
278 	clk_disable(&port->phy_clk);
279 
280 	while (timeout--) {
281 		if (pci_read_reg(chan, SH4A_PCIEPHYSR))
282 			return 0;
283 
284 		udelay(100);
285 	}
286 
287 	return -ETIMEDOUT;
288 }
289 
290 static void __init pcie_reset(struct sh7786_pcie_port *port)
291 {
292 	struct pci_channel *chan = port->hose;
293 
294 	pci_write_reg(chan, 1, SH4A_PCIESRSTR);
295 	pci_write_reg(chan, 0, SH4A_PCIETCTLR);
296 	pci_write_reg(chan, 0, SH4A_PCIESRSTR);
297 	pci_write_reg(chan, 0, SH4A_PCIETXVC0SR);
298 }
299 
300 static int __init pcie_init(struct sh7786_pcie_port *port)
301 {
302 	struct pci_channel *chan = port->hose;
303 	unsigned int data;
304 	phys_addr_t memphys;
305 	size_t memsize;
306 	int ret, i, win;
307 
308 	/* Begin initialization */
309 	pcie_reset(port);
310 
311 	/*
312 	 * Initial header for port config space is type 1, set the device
313 	 * class to match. Hardware takes care of propagating the IDSETR
314 	 * settings, so there is no need to bother with a quirk.
315 	 */
316 	pci_write_reg(chan, PCI_CLASS_BRIDGE_PCI << 16, SH4A_PCIEIDSETR1);
317 
318 	/* Initialize default capabilities. */
319 	data = pci_read_reg(chan, SH4A_PCIEEXPCAP0);
320 	data &= ~(PCI_EXP_FLAGS_TYPE << 16);
321 
322 	if (port->endpoint)
323 		data |= PCI_EXP_TYPE_ENDPOINT << 20;
324 	else
325 		data |= PCI_EXP_TYPE_ROOT_PORT << 20;
326 
327 	data |= PCI_CAP_ID_EXP;
328 	pci_write_reg(chan, data, SH4A_PCIEEXPCAP0);
329 
330 	/* Enable data link layer active state reporting */
331 	pci_write_reg(chan, PCI_EXP_LNKCAP_DLLLARC, SH4A_PCIEEXPCAP3);
332 
333 	/* Enable extended sync and ASPM L0s support */
334 	data = pci_read_reg(chan, SH4A_PCIEEXPCAP4);
335 	data &= ~PCI_EXP_LNKCTL_ASPMC;
336 	data |= PCI_EXP_LNKCTL_ES | 1;
337 	pci_write_reg(chan, data, SH4A_PCIEEXPCAP4);
338 
339 	/* Write out the physical slot number */
340 	data = pci_read_reg(chan, SH4A_PCIEEXPCAP5);
341 	data &= ~PCI_EXP_SLTCAP_PSN;
342 	data |= (port->index + 1) << 19;
343 	pci_write_reg(chan, data, SH4A_PCIEEXPCAP5);
344 
345 	/* Set the completion timer timeout to the maximum 32ms. */
346 	data = pci_read_reg(chan, SH4A_PCIETLCTLR);
347 	data &= ~0x3f00;
348 	data |= 0x32 << 8;
349 	pci_write_reg(chan, data, SH4A_PCIETLCTLR);
350 
351 	/*
352 	 * Set fast training sequences to the maximum 255,
353 	 * and enable MAC data scrambling.
354 	 */
355 	data = pci_read_reg(chan, SH4A_PCIEMACCTLR);
356 	data &= ~PCIEMACCTLR_SCR_DIS;
357 	data |= (0xff << 16);
358 	pci_write_reg(chan, data, SH4A_PCIEMACCTLR);
359 
360 	memphys = __pa(memory_start);
361 	memsize = roundup_pow_of_two(memory_end - memory_start);
362 
363 	/*
364 	 * If there's more than 512MB of memory, we need to roll over to
365 	 * LAR1/LAMR1.
366 	 */
367 	if (memsize > SZ_512M) {
368 		pci_write_reg(chan, memphys + SZ_512M, SH4A_PCIELAR1);
369 		pci_write_reg(chan, ((memsize - SZ_512M) - SZ_256) | 1,
370 			      SH4A_PCIELAMR1);
371 		memsize = SZ_512M;
372 	} else {
373 		/*
374 		 * Otherwise just zero it out and disable it.
375 		 */
376 		pci_write_reg(chan, 0, SH4A_PCIELAR1);
377 		pci_write_reg(chan, 0, SH4A_PCIELAMR1);
378 	}
379 
380 	/*
381 	 * LAR0/LAMR0 covers up to the first 512MB, which is enough to
382 	 * cover all of lowmem on most platforms.
383 	 */
384 	pci_write_reg(chan, memphys, SH4A_PCIELAR0);
385 	pci_write_reg(chan, (memsize - SZ_256) | 1, SH4A_PCIELAMR0);
386 
387 	/* Finish initialization */
388 	data = pci_read_reg(chan, SH4A_PCIETCTLR);
389 	data |= 0x1;
390 	pci_write_reg(chan, data, SH4A_PCIETCTLR);
391 
392 	/* Let things settle down a bit.. */
393 	mdelay(100);
394 
395 	/* Enable DL_Active Interrupt generation */
396 	data = pci_read_reg(chan, SH4A_PCIEDLINTENR);
397 	data |= PCIEDLINTENR_DLL_ACT_ENABLE;
398 	pci_write_reg(chan, data, SH4A_PCIEDLINTENR);
399 
400 	/* Disable MAC data scrambling. */
401 	data = pci_read_reg(chan, SH4A_PCIEMACCTLR);
402 	data |= PCIEMACCTLR_SCR_DIS | (0xff << 16);
403 	pci_write_reg(chan, data, SH4A_PCIEMACCTLR);
404 
405 	/*
406 	 * This will timeout if we don't have a link, but we permit the
407 	 * port to register anyways in order to support hotplug on future
408 	 * hardware.
409 	 */
410 	ret = pci_wait_for_irq(chan, MASK_INT_TX_CTRL);
411 
412 	data = pci_read_reg(chan, SH4A_PCIEPCICONF1);
413 	data &= ~(PCI_STATUS_DEVSEL_MASK << 16);
414 	data |= PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER |
415 		(PCI_STATUS_CAP_LIST | PCI_STATUS_DEVSEL_FAST) << 16;
416 	pci_write_reg(chan, data, SH4A_PCIEPCICONF1);
417 
418 	pci_write_reg(chan, 0x80888000, SH4A_PCIETXVC0DCTLR);
419 	pci_write_reg(chan, 0x00222000, SH4A_PCIERXVC0DCTLR);
420 
421 	wmb();
422 
423 	if (ret == 0) {
424 		data = pci_read_reg(chan, SH4A_PCIEMACSR);
425 		printk(KERN_NOTICE "PCI: PCIe#%d x%d link detected\n",
426 		       port->index, (data >> 20) & 0x3f);
427 	} else
428 		printk(KERN_NOTICE "PCI: PCIe#%d link down\n",
429 		       port->index);
430 
431 	for (i = win = 0; i < chan->nr_resources; i++) {
432 		struct resource *res = chan->resources + i;
433 		resource_size_t size;
434 		u32 mask;
435 
436 		/*
437 		 * We can't use the 32-bit mode windows in legacy 29-bit
438 		 * mode, so just skip them entirely.
439 		 */
440 		if ((res->flags & IORESOURCE_MEM_32BIT) && __in_29bit_mode())
441 			continue;
442 
443 		pci_write_reg(chan, 0x00000000, SH4A_PCIEPTCTLR(win));
444 
445 		/*
446 		 * The PAMR mask is calculated in units of 256kB, which
447 		 * keeps things pretty simple.
448 		 */
449 		size = resource_size(res);
450 		mask = (roundup_pow_of_two(size) / SZ_256K) - 1;
451 		pci_write_reg(chan, mask << 18, SH4A_PCIEPAMR(win));
452 
453 		pci_write_reg(chan, upper_32_bits(res->start),
454 			      SH4A_PCIEPARH(win));
455 		pci_write_reg(chan, lower_32_bits(res->start),
456 			      SH4A_PCIEPARL(win));
457 
458 		mask = MASK_PARE;
459 		if (res->flags & IORESOURCE_IO)
460 			mask |= MASK_SPC;
461 
462 		pci_write_reg(chan, mask, SH4A_PCIEPTCTLR(win));
463 
464 		win++;
465 	}
466 
467 	return 0;
468 }
469 
470 int __init pcibios_map_platform_irq(const struct pci_dev *pdev, u8 slot, u8 pin)
471 {
472         return evt2irq(0xae0);
473 }
474 
475 static int __init sh7786_pcie_core_init(void)
476 {
477 	/* Return the number of ports */
478 	return test_mode_pin(MODE_PIN12) ? 3 : 2;
479 }
480 
481 static void __init sh7786_pcie_init_hw(void *data, async_cookie_t cookie)
482 {
483 	struct sh7786_pcie_port *port = data;
484 	int ret;
485 
486 	/*
487 	 * Check if we are configured in endpoint or root complex mode,
488 	 * this is a fixed pin setting that applies to all PCIe ports.
489 	 */
490 	port->endpoint = test_mode_pin(MODE_PIN11);
491 
492 	/*
493 	 * Setup clocks, needed both for PHY and PCIe registers.
494 	 */
495 	ret = pcie_clk_init(port);
496 	if (unlikely(ret < 0)) {
497 		pr_err("clock initialization failed for port#%d\n",
498 		       port->index);
499 		return;
500 	}
501 
502 	ret = phy_init(port);
503 	if (unlikely(ret < 0)) {
504 		pr_err("phy initialization failed for port#%d\n",
505 		       port->index);
506 		return;
507 	}
508 
509 	ret = pcie_init(port);
510 	if (unlikely(ret < 0)) {
511 		pr_err("core initialization failed for port#%d\n",
512 			       port->index);
513 		return;
514 	}
515 
516 	/* In the interest of preserving device ordering, synchronize */
517 	async_synchronize_cookie(cookie);
518 
519 	register_pci_controller(port->hose);
520 }
521 
522 static struct sh7786_pcie_hwops sh7786_65nm_pcie_hwops __initdata = {
523 	.core_init	= sh7786_pcie_core_init,
524 	.port_init_hw	= sh7786_pcie_init_hw,
525 };
526 
527 static int __init sh7786_pcie_init(void)
528 {
529 	struct clk *platclk;
530 	int i;
531 
532 	printk(KERN_NOTICE "PCI: Starting initialization.\n");
533 
534 	sh7786_pcie_hwops = &sh7786_65nm_pcie_hwops;
535 
536 	nr_ports = sh7786_pcie_hwops->core_init();
537 	BUG_ON(nr_ports > ARRAY_SIZE(sh7786_pci_channels));
538 
539 	if (unlikely(nr_ports == 0))
540 		return -ENODEV;
541 
542 	sh7786_pcie_ports = kzalloc(nr_ports * sizeof(struct sh7786_pcie_port),
543 				    GFP_KERNEL);
544 	if (unlikely(!sh7786_pcie_ports))
545 		return -ENOMEM;
546 
547 	/*
548 	 * Fetch any optional platform clock associated with this block.
549 	 *
550 	 * This is a rather nasty hack for boards with spec-mocking FPGAs
551 	 * that have a secondary set of clocks outside of the on-chip
552 	 * ones that need to be accounted for before there is any chance
553 	 * of touching the existing MSTP bits or CPG clocks.
554 	 */
555 	platclk = clk_get(NULL, "pcie_plat_clk");
556 	if (IS_ERR(platclk)) {
557 		/* Sane hardware should probably get a WARN_ON.. */
558 		platclk = NULL;
559 	}
560 
561 	clk_enable(platclk);
562 
563 	printk(KERN_NOTICE "PCI: probing %d ports.\n", nr_ports);
564 
565 	for (i = 0; i < nr_ports; i++) {
566 		struct sh7786_pcie_port *port = sh7786_pcie_ports + i;
567 
568 		port->index		= i;
569 		port->hose		= sh7786_pci_channels + i;
570 		port->hose->io_map_base	= port->hose->resources[0].start;
571 
572 		async_schedule(sh7786_pcie_hwops->port_init_hw, port);
573 	}
574 
575 	async_synchronize_full();
576 
577 	return 0;
578 }
579 arch_initcall(sh7786_pcie_init);
580