1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright Altera Corporation (C) 2013-2015. All rights reserved
4 *
5 * Author: Ley Foon Tan <lftan@altera.com>
6 * Description: Altera PCIe host controller driver
7 */
8
9 #include <linux/delay.h>
10 #include <linux/interrupt.h>
11 #include <linux/irqchip/chained_irq.h>
12 #include <linux/irqdomain.h>
13 #include <linux/init.h>
14 #include <linux/module.h>
15 #include <linux/of.h>
16 #include <linux/of_pci.h>
17 #include <linux/pci.h>
18 #include <linux/platform_device.h>
19 #include <linux/slab.h>
20
21 #include "../pci.h"
22
23 #define RP_TX_REG0 0x2000
24 #define RP_TX_REG1 0x2004
25 #define RP_TX_CNTRL 0x2008
26 #define RP_TX_EOP 0x2
27 #define RP_TX_SOP 0x1
28 #define RP_RXCPL_STATUS 0x2010
29 #define RP_RXCPL_EOP 0x2
30 #define RP_RXCPL_SOP 0x1
31 #define RP_RXCPL_REG0 0x2014
32 #define RP_RXCPL_REG1 0x2018
33 #define P2A_INT_STATUS 0x3060
34 #define P2A_INT_STS_ALL 0xf
35 #define P2A_INT_ENABLE 0x3070
36 #define P2A_INT_ENA_ALL 0xf
37 #define RP_LTSSM 0x3c64
38 #define RP_LTSSM_MASK 0x1f
39 #define LTSSM_L0 0xf
40
41 #define S10_RP_TX_CNTRL 0x2004
42 #define S10_RP_RXCPL_REG 0x2008
43 #define S10_RP_RXCPL_STATUS 0x200C
44 #define S10_RP_CFG_ADDR(pcie, reg) \
45 (((pcie)->hip_base) + (reg) + (1 << 20))
46 #define S10_RP_SECONDARY(pcie) \
47 readb(S10_RP_CFG_ADDR(pcie, PCI_SECONDARY_BUS))
48
49 /* TLP configuration type 0 and 1 */
50 #define TLP_FMTTYPE_CFGRD0 0x04 /* Configuration Read Type 0 */
51 #define TLP_FMTTYPE_CFGWR0 0x44 /* Configuration Write Type 0 */
52 #define TLP_FMTTYPE_CFGRD1 0x05 /* Configuration Read Type 1 */
53 #define TLP_FMTTYPE_CFGWR1 0x45 /* Configuration Write Type 1 */
54 #define TLP_PAYLOAD_SIZE 0x01
55 #define TLP_READ_TAG 0x1d
56 #define TLP_WRITE_TAG 0x10
57 #define RP_DEVFN 0
58 #define TLP_CFG_DW0(pcie, cfg) \
59 (((cfg) << 24) | \
60 TLP_PAYLOAD_SIZE)
61 #define TLP_CFG_DW1(pcie, tag, be) \
62 (((PCI_DEVID(pcie->root_bus_nr, RP_DEVFN)) << 16) | (tag << 8) | (be))
63 #define TLP_CFG_DW2(bus, devfn, offset) \
64 (((bus) << 24) | ((devfn) << 16) | (offset))
65 #define TLP_COMP_STATUS(s) (((s) >> 13) & 7)
66 #define TLP_BYTE_COUNT(s) (((s) >> 0) & 0xfff)
67 #define TLP_HDR_SIZE 3
68 #define TLP_LOOP 500
69
70 #define LINK_UP_TIMEOUT HZ
71 #define LINK_RETRAIN_TIMEOUT HZ
72
73 #define DWORD_MASK 3
74
75 #define S10_TLP_FMTTYPE_CFGRD0 0x05
76 #define S10_TLP_FMTTYPE_CFGRD1 0x04
77 #define S10_TLP_FMTTYPE_CFGWR0 0x45
78 #define S10_TLP_FMTTYPE_CFGWR1 0x44
79
80 enum altera_pcie_version {
81 ALTERA_PCIE_V1 = 0,
82 ALTERA_PCIE_V2,
83 };
84
85 struct altera_pcie {
86 struct platform_device *pdev;
87 void __iomem *cra_base;
88 void __iomem *hip_base;
89 int irq;
90 u8 root_bus_nr;
91 struct irq_domain *irq_domain;
92 struct resource bus_range;
93 const struct altera_pcie_data *pcie_data;
94 };
95
96 struct altera_pcie_ops {
97 int (*tlp_read_pkt)(struct altera_pcie *pcie, u32 *value);
98 void (*tlp_write_pkt)(struct altera_pcie *pcie, u32 *headers,
99 u32 data, bool align);
100 bool (*get_link_status)(struct altera_pcie *pcie);
101 int (*rp_read_cfg)(struct altera_pcie *pcie, int where,
102 int size, u32 *value);
103 int (*rp_write_cfg)(struct altera_pcie *pcie, u8 busno,
104 int where, int size, u32 value);
105 };
106
107 struct altera_pcie_data {
108 const struct altera_pcie_ops *ops;
109 enum altera_pcie_version version;
110 u32 cap_offset; /* PCIe capability structure register offset */
111 u32 cfgrd0;
112 u32 cfgrd1;
113 u32 cfgwr0;
114 u32 cfgwr1;
115 };
116
117 struct tlp_rp_regpair_t {
118 u32 ctrl;
119 u32 reg0;
120 u32 reg1;
121 };
122
cra_writel(struct altera_pcie * pcie,const u32 value,const u32 reg)123 static inline void cra_writel(struct altera_pcie *pcie, const u32 value,
124 const u32 reg)
125 {
126 writel_relaxed(value, pcie->cra_base + reg);
127 }
128
cra_readl(struct altera_pcie * pcie,const u32 reg)129 static inline u32 cra_readl(struct altera_pcie *pcie, const u32 reg)
130 {
131 return readl_relaxed(pcie->cra_base + reg);
132 }
133
altera_pcie_link_up(struct altera_pcie * pcie)134 static bool altera_pcie_link_up(struct altera_pcie *pcie)
135 {
136 return !!((cra_readl(pcie, RP_LTSSM) & RP_LTSSM_MASK) == LTSSM_L0);
137 }
138
s10_altera_pcie_link_up(struct altera_pcie * pcie)139 static bool s10_altera_pcie_link_up(struct altera_pcie *pcie)
140 {
141 void __iomem *addr = S10_RP_CFG_ADDR(pcie,
142 pcie->pcie_data->cap_offset +
143 PCI_EXP_LNKSTA);
144
145 return !!(readw(addr) & PCI_EXP_LNKSTA_DLLLA);
146 }
147
148 /*
149 * Altera PCIe port uses BAR0 of RC's configuration space as the translation
150 * from PCI bus to native BUS. Entire DDR region is mapped into PCIe space
151 * using these registers, so it can be reached by DMA from EP devices.
152 * This BAR0 will also access to MSI vector when receiving MSI/MSIX interrupt
153 * from EP devices, eventually trigger interrupt to GIC. The BAR0 of bridge
154 * should be hidden during enumeration to avoid the sizing and resource
155 * allocation by PCIe core.
156 */
altera_pcie_hide_rc_bar(struct pci_bus * bus,unsigned int devfn,int offset)157 static bool altera_pcie_hide_rc_bar(struct pci_bus *bus, unsigned int devfn,
158 int offset)
159 {
160 if (pci_is_root_bus(bus) && (devfn == 0) &&
161 (offset == PCI_BASE_ADDRESS_0))
162 return true;
163
164 return false;
165 }
166
tlp_write_tx(struct altera_pcie * pcie,struct tlp_rp_regpair_t * tlp_rp_regdata)167 static void tlp_write_tx(struct altera_pcie *pcie,
168 struct tlp_rp_regpair_t *tlp_rp_regdata)
169 {
170 cra_writel(pcie, tlp_rp_regdata->reg0, RP_TX_REG0);
171 cra_writel(pcie, tlp_rp_regdata->reg1, RP_TX_REG1);
172 cra_writel(pcie, tlp_rp_regdata->ctrl, RP_TX_CNTRL);
173 }
174
s10_tlp_write_tx(struct altera_pcie * pcie,u32 reg0,u32 ctrl)175 static void s10_tlp_write_tx(struct altera_pcie *pcie, u32 reg0, u32 ctrl)
176 {
177 cra_writel(pcie, reg0, RP_TX_REG0);
178 cra_writel(pcie, ctrl, S10_RP_TX_CNTRL);
179 }
180
altera_pcie_valid_device(struct altera_pcie * pcie,struct pci_bus * bus,int dev)181 static bool altera_pcie_valid_device(struct altera_pcie *pcie,
182 struct pci_bus *bus, int dev)
183 {
184 /* If there is no link, then there is no device */
185 if (bus->number != pcie->root_bus_nr) {
186 if (!pcie->pcie_data->ops->get_link_status(pcie))
187 return false;
188 }
189
190 /* access only one slot on each root port */
191 if (bus->number == pcie->root_bus_nr && dev > 0)
192 return false;
193
194 return true;
195 }
196
tlp_read_packet(struct altera_pcie * pcie,u32 * value)197 static int tlp_read_packet(struct altera_pcie *pcie, u32 *value)
198 {
199 int i;
200 bool sop = false;
201 u32 ctrl;
202 u32 reg0, reg1;
203 u32 comp_status = 1;
204
205 /*
206 * Minimum 2 loops to read TLP headers and 1 loop to read data
207 * payload.
208 */
209 for (i = 0; i < TLP_LOOP; i++) {
210 ctrl = cra_readl(pcie, RP_RXCPL_STATUS);
211 if ((ctrl & RP_RXCPL_SOP) || (ctrl & RP_RXCPL_EOP) || sop) {
212 reg0 = cra_readl(pcie, RP_RXCPL_REG0);
213 reg1 = cra_readl(pcie, RP_RXCPL_REG1);
214
215 if (ctrl & RP_RXCPL_SOP) {
216 sop = true;
217 comp_status = TLP_COMP_STATUS(reg1);
218 }
219
220 if (ctrl & RP_RXCPL_EOP) {
221 if (comp_status)
222 return PCIBIOS_DEVICE_NOT_FOUND;
223
224 if (value)
225 *value = reg0;
226
227 return PCIBIOS_SUCCESSFUL;
228 }
229 }
230 udelay(5);
231 }
232
233 return PCIBIOS_DEVICE_NOT_FOUND;
234 }
235
s10_tlp_read_packet(struct altera_pcie * pcie,u32 * value)236 static int s10_tlp_read_packet(struct altera_pcie *pcie, u32 *value)
237 {
238 u32 ctrl;
239 u32 comp_status;
240 u32 dw[4];
241 u32 count;
242 struct device *dev = &pcie->pdev->dev;
243
244 for (count = 0; count < TLP_LOOP; count++) {
245 ctrl = cra_readl(pcie, S10_RP_RXCPL_STATUS);
246 if (ctrl & RP_RXCPL_SOP) {
247 /* Read first DW */
248 dw[0] = cra_readl(pcie, S10_RP_RXCPL_REG);
249 break;
250 }
251
252 udelay(5);
253 }
254
255 /* SOP detection failed, return error */
256 if (count == TLP_LOOP)
257 return PCIBIOS_DEVICE_NOT_FOUND;
258
259 count = 1;
260
261 /* Poll for EOP */
262 while (count < ARRAY_SIZE(dw)) {
263 ctrl = cra_readl(pcie, S10_RP_RXCPL_STATUS);
264 dw[count++] = cra_readl(pcie, S10_RP_RXCPL_REG);
265 if (ctrl & RP_RXCPL_EOP) {
266 comp_status = TLP_COMP_STATUS(dw[1]);
267 if (comp_status)
268 return PCIBIOS_DEVICE_NOT_FOUND;
269
270 if (value && TLP_BYTE_COUNT(dw[1]) == sizeof(u32) &&
271 count == 4)
272 *value = dw[3];
273
274 return PCIBIOS_SUCCESSFUL;
275 }
276 }
277
278 dev_warn(dev, "Malformed TLP packet\n");
279
280 return PCIBIOS_DEVICE_NOT_FOUND;
281 }
282
tlp_write_packet(struct altera_pcie * pcie,u32 * headers,u32 data,bool align)283 static void tlp_write_packet(struct altera_pcie *pcie, u32 *headers,
284 u32 data, bool align)
285 {
286 struct tlp_rp_regpair_t tlp_rp_regdata;
287
288 tlp_rp_regdata.reg0 = headers[0];
289 tlp_rp_regdata.reg1 = headers[1];
290 tlp_rp_regdata.ctrl = RP_TX_SOP;
291 tlp_write_tx(pcie, &tlp_rp_regdata);
292
293 if (align) {
294 tlp_rp_regdata.reg0 = headers[2];
295 tlp_rp_regdata.reg1 = 0;
296 tlp_rp_regdata.ctrl = 0;
297 tlp_write_tx(pcie, &tlp_rp_regdata);
298
299 tlp_rp_regdata.reg0 = data;
300 tlp_rp_regdata.reg1 = 0;
301 } else {
302 tlp_rp_regdata.reg0 = headers[2];
303 tlp_rp_regdata.reg1 = data;
304 }
305
306 tlp_rp_regdata.ctrl = RP_TX_EOP;
307 tlp_write_tx(pcie, &tlp_rp_regdata);
308 }
309
s10_tlp_write_packet(struct altera_pcie * pcie,u32 * headers,u32 data,bool dummy)310 static void s10_tlp_write_packet(struct altera_pcie *pcie, u32 *headers,
311 u32 data, bool dummy)
312 {
313 s10_tlp_write_tx(pcie, headers[0], RP_TX_SOP);
314 s10_tlp_write_tx(pcie, headers[1], 0);
315 s10_tlp_write_tx(pcie, headers[2], 0);
316 s10_tlp_write_tx(pcie, data, RP_TX_EOP);
317 }
318
get_tlp_header(struct altera_pcie * pcie,u8 bus,u32 devfn,int where,u8 byte_en,bool read,u32 * headers)319 static void get_tlp_header(struct altera_pcie *pcie, u8 bus, u32 devfn,
320 int where, u8 byte_en, bool read, u32 *headers)
321 {
322 u8 cfg;
323 u8 cfg0 = read ? pcie->pcie_data->cfgrd0 : pcie->pcie_data->cfgwr0;
324 u8 cfg1 = read ? pcie->pcie_data->cfgrd1 : pcie->pcie_data->cfgwr1;
325 u8 tag = read ? TLP_READ_TAG : TLP_WRITE_TAG;
326
327 if (pcie->pcie_data->version == ALTERA_PCIE_V1)
328 cfg = (bus == pcie->root_bus_nr) ? cfg0 : cfg1;
329 else
330 cfg = (bus > S10_RP_SECONDARY(pcie)) ? cfg0 : cfg1;
331
332 headers[0] = TLP_CFG_DW0(pcie, cfg);
333 headers[1] = TLP_CFG_DW1(pcie, tag, byte_en);
334 headers[2] = TLP_CFG_DW2(bus, devfn, where);
335 }
336
tlp_cfg_dword_read(struct altera_pcie * pcie,u8 bus,u32 devfn,int where,u8 byte_en,u32 * value)337 static int tlp_cfg_dword_read(struct altera_pcie *pcie, u8 bus, u32 devfn,
338 int where, u8 byte_en, u32 *value)
339 {
340 u32 headers[TLP_HDR_SIZE];
341
342 get_tlp_header(pcie, bus, devfn, where, byte_en, true,
343 headers);
344
345 pcie->pcie_data->ops->tlp_write_pkt(pcie, headers, 0, false);
346
347 return pcie->pcie_data->ops->tlp_read_pkt(pcie, value);
348 }
349
tlp_cfg_dword_write(struct altera_pcie * pcie,u8 bus,u32 devfn,int where,u8 byte_en,u32 value)350 static int tlp_cfg_dword_write(struct altera_pcie *pcie, u8 bus, u32 devfn,
351 int where, u8 byte_en, u32 value)
352 {
353 u32 headers[TLP_HDR_SIZE];
354 int ret;
355
356 get_tlp_header(pcie, bus, devfn, where, byte_en, false,
357 headers);
358
359 /* check alignment to Qword */
360 if ((where & 0x7) == 0)
361 pcie->pcie_data->ops->tlp_write_pkt(pcie, headers,
362 value, true);
363 else
364 pcie->pcie_data->ops->tlp_write_pkt(pcie, headers,
365 value, false);
366
367 ret = pcie->pcie_data->ops->tlp_read_pkt(pcie, NULL);
368 if (ret != PCIBIOS_SUCCESSFUL)
369 return ret;
370
371 /*
372 * Monitor changes to PCI_PRIMARY_BUS register on root port
373 * and update local copy of root bus number accordingly.
374 */
375 if ((bus == pcie->root_bus_nr) && (where == PCI_PRIMARY_BUS))
376 pcie->root_bus_nr = (u8)(value);
377
378 return PCIBIOS_SUCCESSFUL;
379 }
380
s10_rp_read_cfg(struct altera_pcie * pcie,int where,int size,u32 * value)381 static int s10_rp_read_cfg(struct altera_pcie *pcie, int where,
382 int size, u32 *value)
383 {
384 void __iomem *addr = S10_RP_CFG_ADDR(pcie, where);
385
386 switch (size) {
387 case 1:
388 *value = readb(addr);
389 break;
390 case 2:
391 *value = readw(addr);
392 break;
393 default:
394 *value = readl(addr);
395 break;
396 }
397
398 return PCIBIOS_SUCCESSFUL;
399 }
400
s10_rp_write_cfg(struct altera_pcie * pcie,u8 busno,int where,int size,u32 value)401 static int s10_rp_write_cfg(struct altera_pcie *pcie, u8 busno,
402 int where, int size, u32 value)
403 {
404 void __iomem *addr = S10_RP_CFG_ADDR(pcie, where);
405
406 switch (size) {
407 case 1:
408 writeb(value, addr);
409 break;
410 case 2:
411 writew(value, addr);
412 break;
413 default:
414 writel(value, addr);
415 break;
416 }
417
418 /*
419 * Monitor changes to PCI_PRIMARY_BUS register on root port
420 * and update local copy of root bus number accordingly.
421 */
422 if (busno == pcie->root_bus_nr && where == PCI_PRIMARY_BUS)
423 pcie->root_bus_nr = value & 0xff;
424
425 return PCIBIOS_SUCCESSFUL;
426 }
427
_altera_pcie_cfg_read(struct altera_pcie * pcie,u8 busno,unsigned int devfn,int where,int size,u32 * value)428 static int _altera_pcie_cfg_read(struct altera_pcie *pcie, u8 busno,
429 unsigned int devfn, int where, int size,
430 u32 *value)
431 {
432 int ret;
433 u32 data;
434 u8 byte_en;
435
436 if (busno == pcie->root_bus_nr && pcie->pcie_data->ops->rp_read_cfg)
437 return pcie->pcie_data->ops->rp_read_cfg(pcie, where,
438 size, value);
439
440 switch (size) {
441 case 1:
442 byte_en = 1 << (where & 3);
443 break;
444 case 2:
445 byte_en = 3 << (where & 3);
446 break;
447 default:
448 byte_en = 0xf;
449 break;
450 }
451
452 ret = tlp_cfg_dword_read(pcie, busno, devfn,
453 (where & ~DWORD_MASK), byte_en, &data);
454 if (ret != PCIBIOS_SUCCESSFUL)
455 return ret;
456
457 switch (size) {
458 case 1:
459 *value = (data >> (8 * (where & 0x3))) & 0xff;
460 break;
461 case 2:
462 *value = (data >> (8 * (where & 0x2))) & 0xffff;
463 break;
464 default:
465 *value = data;
466 break;
467 }
468
469 return PCIBIOS_SUCCESSFUL;
470 }
471
_altera_pcie_cfg_write(struct altera_pcie * pcie,u8 busno,unsigned int devfn,int where,int size,u32 value)472 static int _altera_pcie_cfg_write(struct altera_pcie *pcie, u8 busno,
473 unsigned int devfn, int where, int size,
474 u32 value)
475 {
476 u32 data32;
477 u32 shift = 8 * (where & 3);
478 u8 byte_en;
479
480 if (busno == pcie->root_bus_nr && pcie->pcie_data->ops->rp_write_cfg)
481 return pcie->pcie_data->ops->rp_write_cfg(pcie, busno,
482 where, size, value);
483
484 switch (size) {
485 case 1:
486 data32 = (value & 0xff) << shift;
487 byte_en = 1 << (where & 3);
488 break;
489 case 2:
490 data32 = (value & 0xffff) << shift;
491 byte_en = 3 << (where & 3);
492 break;
493 default:
494 data32 = value;
495 byte_en = 0xf;
496 break;
497 }
498
499 return tlp_cfg_dword_write(pcie, busno, devfn, (where & ~DWORD_MASK),
500 byte_en, data32);
501 }
502
altera_pcie_cfg_read(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 * value)503 static int altera_pcie_cfg_read(struct pci_bus *bus, unsigned int devfn,
504 int where, int size, u32 *value)
505 {
506 struct altera_pcie *pcie = bus->sysdata;
507
508 if (altera_pcie_hide_rc_bar(bus, devfn, where))
509 return PCIBIOS_BAD_REGISTER_NUMBER;
510
511 if (!altera_pcie_valid_device(pcie, bus, PCI_SLOT(devfn)))
512 return PCIBIOS_DEVICE_NOT_FOUND;
513
514 return _altera_pcie_cfg_read(pcie, bus->number, devfn, where, size,
515 value);
516 }
517
altera_pcie_cfg_write(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 value)518 static int altera_pcie_cfg_write(struct pci_bus *bus, unsigned int devfn,
519 int where, int size, u32 value)
520 {
521 struct altera_pcie *pcie = bus->sysdata;
522
523 if (altera_pcie_hide_rc_bar(bus, devfn, where))
524 return PCIBIOS_BAD_REGISTER_NUMBER;
525
526 if (!altera_pcie_valid_device(pcie, bus, PCI_SLOT(devfn)))
527 return PCIBIOS_DEVICE_NOT_FOUND;
528
529 return _altera_pcie_cfg_write(pcie, bus->number, devfn, where, size,
530 value);
531 }
532
533 static struct pci_ops altera_pcie_ops = {
534 .read = altera_pcie_cfg_read,
535 .write = altera_pcie_cfg_write,
536 };
537
altera_read_cap_word(struct altera_pcie * pcie,u8 busno,unsigned int devfn,int offset,u16 * value)538 static int altera_read_cap_word(struct altera_pcie *pcie, u8 busno,
539 unsigned int devfn, int offset, u16 *value)
540 {
541 u32 data;
542 int ret;
543
544 ret = _altera_pcie_cfg_read(pcie, busno, devfn,
545 pcie->pcie_data->cap_offset + offset,
546 sizeof(*value),
547 &data);
548 *value = data;
549 return ret;
550 }
551
altera_write_cap_word(struct altera_pcie * pcie,u8 busno,unsigned int devfn,int offset,u16 value)552 static int altera_write_cap_word(struct altera_pcie *pcie, u8 busno,
553 unsigned int devfn, int offset, u16 value)
554 {
555 return _altera_pcie_cfg_write(pcie, busno, devfn,
556 pcie->pcie_data->cap_offset + offset,
557 sizeof(value),
558 value);
559 }
560
altera_wait_link_retrain(struct altera_pcie * pcie)561 static void altera_wait_link_retrain(struct altera_pcie *pcie)
562 {
563 struct device *dev = &pcie->pdev->dev;
564 u16 reg16;
565 unsigned long start_jiffies;
566
567 /* Wait for link training end. */
568 start_jiffies = jiffies;
569 for (;;) {
570 altera_read_cap_word(pcie, pcie->root_bus_nr, RP_DEVFN,
571 PCI_EXP_LNKSTA, ®16);
572 if (!(reg16 & PCI_EXP_LNKSTA_LT))
573 break;
574
575 if (time_after(jiffies, start_jiffies + LINK_RETRAIN_TIMEOUT)) {
576 dev_err(dev, "link retrain timeout\n");
577 break;
578 }
579 udelay(100);
580 }
581
582 /* Wait for link is up */
583 start_jiffies = jiffies;
584 for (;;) {
585 if (pcie->pcie_data->ops->get_link_status(pcie))
586 break;
587
588 if (time_after(jiffies, start_jiffies + LINK_UP_TIMEOUT)) {
589 dev_err(dev, "link up timeout\n");
590 break;
591 }
592 udelay(100);
593 }
594 }
595
altera_pcie_retrain(struct altera_pcie * pcie)596 static void altera_pcie_retrain(struct altera_pcie *pcie)
597 {
598 u16 linkcap, linkstat, linkctl;
599
600 if (!pcie->pcie_data->ops->get_link_status(pcie))
601 return;
602
603 /*
604 * Set the retrain bit if the PCIe rootport support > 2.5GB/s, but
605 * current speed is 2.5 GB/s.
606 */
607 altera_read_cap_word(pcie, pcie->root_bus_nr, RP_DEVFN, PCI_EXP_LNKCAP,
608 &linkcap);
609 if ((linkcap & PCI_EXP_LNKCAP_SLS) <= PCI_EXP_LNKCAP_SLS_2_5GB)
610 return;
611
612 altera_read_cap_word(pcie, pcie->root_bus_nr, RP_DEVFN, PCI_EXP_LNKSTA,
613 &linkstat);
614 if ((linkstat & PCI_EXP_LNKSTA_CLS) == PCI_EXP_LNKSTA_CLS_2_5GB) {
615 altera_read_cap_word(pcie, pcie->root_bus_nr, RP_DEVFN,
616 PCI_EXP_LNKCTL, &linkctl);
617 linkctl |= PCI_EXP_LNKCTL_RL;
618 altera_write_cap_word(pcie, pcie->root_bus_nr, RP_DEVFN,
619 PCI_EXP_LNKCTL, linkctl);
620
621 altera_wait_link_retrain(pcie);
622 }
623 }
624
altera_pcie_intx_map(struct irq_domain * domain,unsigned int irq,irq_hw_number_t hwirq)625 static int altera_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
626 irq_hw_number_t hwirq)
627 {
628 irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_simple_irq);
629 irq_set_chip_data(irq, domain->host_data);
630 return 0;
631 }
632
633 static const struct irq_domain_ops intx_domain_ops = {
634 .map = altera_pcie_intx_map,
635 .xlate = pci_irqd_intx_xlate,
636 };
637
altera_pcie_isr(struct irq_desc * desc)638 static void altera_pcie_isr(struct irq_desc *desc)
639 {
640 struct irq_chip *chip = irq_desc_get_chip(desc);
641 struct altera_pcie *pcie;
642 struct device *dev;
643 unsigned long status;
644 u32 bit;
645 int ret;
646
647 chained_irq_enter(chip, desc);
648 pcie = irq_desc_get_handler_data(desc);
649 dev = &pcie->pdev->dev;
650
651 while ((status = cra_readl(pcie, P2A_INT_STATUS)
652 & P2A_INT_STS_ALL) != 0) {
653 for_each_set_bit(bit, &status, PCI_NUM_INTX) {
654 /* clear interrupts */
655 cra_writel(pcie, 1 << bit, P2A_INT_STATUS);
656
657 ret = generic_handle_domain_irq(pcie->irq_domain, bit);
658 if (ret)
659 dev_err_ratelimited(dev, "unexpected IRQ, INT%d\n", bit);
660 }
661 }
662
663 chained_irq_exit(chip, desc);
664 }
665
altera_pcie_init_irq_domain(struct altera_pcie * pcie)666 static int altera_pcie_init_irq_domain(struct altera_pcie *pcie)
667 {
668 struct device *dev = &pcie->pdev->dev;
669 struct device_node *node = dev->of_node;
670
671 /* Setup INTx */
672 pcie->irq_domain = irq_domain_add_linear(node, PCI_NUM_INTX,
673 &intx_domain_ops, pcie);
674 if (!pcie->irq_domain) {
675 dev_err(dev, "Failed to get a INTx IRQ domain\n");
676 return -ENOMEM;
677 }
678
679 return 0;
680 }
681
altera_pcie_irq_teardown(struct altera_pcie * pcie)682 static void altera_pcie_irq_teardown(struct altera_pcie *pcie)
683 {
684 irq_set_chained_handler_and_data(pcie->irq, NULL, NULL);
685 irq_domain_remove(pcie->irq_domain);
686 irq_dispose_mapping(pcie->irq);
687 }
688
altera_pcie_parse_dt(struct altera_pcie * pcie)689 static int altera_pcie_parse_dt(struct altera_pcie *pcie)
690 {
691 struct platform_device *pdev = pcie->pdev;
692
693 pcie->cra_base = devm_platform_ioremap_resource_byname(pdev, "Cra");
694 if (IS_ERR(pcie->cra_base))
695 return PTR_ERR(pcie->cra_base);
696
697 if (pcie->pcie_data->version == ALTERA_PCIE_V2) {
698 pcie->hip_base =
699 devm_platform_ioremap_resource_byname(pdev, "Hip");
700 if (IS_ERR(pcie->hip_base))
701 return PTR_ERR(pcie->hip_base);
702 }
703
704 /* setup IRQ */
705 pcie->irq = platform_get_irq(pdev, 0);
706 if (pcie->irq < 0)
707 return pcie->irq;
708
709 irq_set_chained_handler_and_data(pcie->irq, altera_pcie_isr, pcie);
710 return 0;
711 }
712
altera_pcie_host_init(struct altera_pcie * pcie)713 static void altera_pcie_host_init(struct altera_pcie *pcie)
714 {
715 altera_pcie_retrain(pcie);
716 }
717
718 static const struct altera_pcie_ops altera_pcie_ops_1_0 = {
719 .tlp_read_pkt = tlp_read_packet,
720 .tlp_write_pkt = tlp_write_packet,
721 .get_link_status = altera_pcie_link_up,
722 };
723
724 static const struct altera_pcie_ops altera_pcie_ops_2_0 = {
725 .tlp_read_pkt = s10_tlp_read_packet,
726 .tlp_write_pkt = s10_tlp_write_packet,
727 .get_link_status = s10_altera_pcie_link_up,
728 .rp_read_cfg = s10_rp_read_cfg,
729 .rp_write_cfg = s10_rp_write_cfg,
730 };
731
732 static const struct altera_pcie_data altera_pcie_1_0_data = {
733 .ops = &altera_pcie_ops_1_0,
734 .cap_offset = 0x80,
735 .version = ALTERA_PCIE_V1,
736 .cfgrd0 = TLP_FMTTYPE_CFGRD0,
737 .cfgrd1 = TLP_FMTTYPE_CFGRD1,
738 .cfgwr0 = TLP_FMTTYPE_CFGWR0,
739 .cfgwr1 = TLP_FMTTYPE_CFGWR1,
740 };
741
742 static const struct altera_pcie_data altera_pcie_2_0_data = {
743 .ops = &altera_pcie_ops_2_0,
744 .version = ALTERA_PCIE_V2,
745 .cap_offset = 0x70,
746 .cfgrd0 = S10_TLP_FMTTYPE_CFGRD0,
747 .cfgrd1 = S10_TLP_FMTTYPE_CFGRD1,
748 .cfgwr0 = S10_TLP_FMTTYPE_CFGWR0,
749 .cfgwr1 = S10_TLP_FMTTYPE_CFGWR1,
750 };
751
752 static const struct of_device_id altera_pcie_of_match[] = {
753 {.compatible = "altr,pcie-root-port-1.0",
754 .data = &altera_pcie_1_0_data },
755 {.compatible = "altr,pcie-root-port-2.0",
756 .data = &altera_pcie_2_0_data },
757 {},
758 };
759
altera_pcie_probe(struct platform_device * pdev)760 static int altera_pcie_probe(struct platform_device *pdev)
761 {
762 struct device *dev = &pdev->dev;
763 struct altera_pcie *pcie;
764 struct pci_host_bridge *bridge;
765 int ret;
766 const struct altera_pcie_data *data;
767
768 bridge = devm_pci_alloc_host_bridge(dev, sizeof(*pcie));
769 if (!bridge)
770 return -ENOMEM;
771
772 pcie = pci_host_bridge_priv(bridge);
773 pcie->pdev = pdev;
774 platform_set_drvdata(pdev, pcie);
775
776 data = of_device_get_match_data(&pdev->dev);
777 if (!data)
778 return -ENODEV;
779
780 pcie->pcie_data = data;
781
782 ret = altera_pcie_parse_dt(pcie);
783 if (ret) {
784 dev_err(dev, "Parsing DT failed\n");
785 return ret;
786 }
787
788 ret = altera_pcie_init_irq_domain(pcie);
789 if (ret) {
790 dev_err(dev, "Failed creating IRQ Domain\n");
791 return ret;
792 }
793
794 /* clear all interrupts */
795 cra_writel(pcie, P2A_INT_STS_ALL, P2A_INT_STATUS);
796 /* enable all interrupts */
797 cra_writel(pcie, P2A_INT_ENA_ALL, P2A_INT_ENABLE);
798 altera_pcie_host_init(pcie);
799
800 bridge->sysdata = pcie;
801 bridge->busnr = pcie->root_bus_nr;
802 bridge->ops = &altera_pcie_ops;
803
804 return pci_host_probe(bridge);
805 }
806
altera_pcie_remove(struct platform_device * pdev)807 static void altera_pcie_remove(struct platform_device *pdev)
808 {
809 struct altera_pcie *pcie = platform_get_drvdata(pdev);
810 struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
811
812 pci_stop_root_bus(bridge->bus);
813 pci_remove_root_bus(bridge->bus);
814 altera_pcie_irq_teardown(pcie);
815 }
816
817 static struct platform_driver altera_pcie_driver = {
818 .probe = altera_pcie_probe,
819 .remove_new = altera_pcie_remove,
820 .driver = {
821 .name = "altera-pcie",
822 .of_match_table = altera_pcie_of_match,
823 },
824 };
825
826 MODULE_DEVICE_TABLE(of, altera_pcie_of_match);
827 module_platform_driver(altera_pcie_driver);
828 MODULE_DESCRIPTION("Altera PCIe host controller driver");
829 MODULE_LICENSE("GPL v2");
830