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_t 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
sh7786_pci_fixup(struct pci_dev * dev)135 static void 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
phy_wait_for_ack(struct pci_channel * chan)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
pci_wait_for_irq(struct pci_channel * chan,unsigned int mask)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
phy_write_reg(struct pci_channel * chan,unsigned int addr,unsigned int lane,unsigned int data)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
pcie_clk_init(struct sh7786_pcie_port * port)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
phy_init(struct sh7786_pcie_port * port)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
pcie_reset(struct sh7786_pcie_port * port)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
pcie_init(struct sh7786_pcie_port * port)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
pcibios_map_platform_irq(const struct pci_dev * pdev,u8 slot,u8 pin)470 int __init pcibios_map_platform_irq(const struct pci_dev *pdev, u8 slot, u8 pin)
471 {
472 return evt2irq(0xae0);
473 }
474
sh7786_pcie_core_init(void)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
sh7786_pcie_init_hw(void * data,async_cookie_t cookie)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
sh7786_pcie_init(void)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