Linux Audio

Check our new training course

Loading...
v6.8
  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_REQ_ID(bus, devfn)		(((bus) << 8) | (devfn))
 59#define TLP_CFG_DW0(pcie, cfg)		\
 60		(((cfg) << 24) |	\
 61		  TLP_PAYLOAD_SIZE)
 62#define TLP_CFG_DW1(pcie, tag, be)	\
 63	(((TLP_REQ_ID(pcie->root_bus_nr,  RP_DEVFN)) << 16) | (tag << 8) | (be))
 64#define TLP_CFG_DW2(bus, devfn, offset)	\
 65				(((bus) << 24) | ((devfn) << 16) | (offset))
 66#define TLP_COMP_STATUS(s)		(((s) >> 13) & 7)
 67#define TLP_BYTE_COUNT(s)		(((s) >> 0) & 0xfff)
 68#define TLP_HDR_SIZE			3
 69#define TLP_LOOP			500
 70
 71#define LINK_UP_TIMEOUT			HZ
 72#define LINK_RETRAIN_TIMEOUT		HZ
 73
 74#define DWORD_MASK			3
 75
 76#define S10_TLP_FMTTYPE_CFGRD0		0x05
 77#define S10_TLP_FMTTYPE_CFGRD1		0x04
 78#define S10_TLP_FMTTYPE_CFGWR0		0x45
 79#define S10_TLP_FMTTYPE_CFGWR1		0x44
 80
 81enum altera_pcie_version {
 82	ALTERA_PCIE_V1 = 0,
 83	ALTERA_PCIE_V2,
 84};
 85
 86struct altera_pcie {
 87	struct platform_device	*pdev;
 88	void __iomem		*cra_base;
 89	void __iomem		*hip_base;
 90	int			irq;
 91	u8			root_bus_nr;
 92	struct irq_domain	*irq_domain;
 93	struct resource		bus_range;
 
 94	const struct altera_pcie_data	*pcie_data;
 95};
 96
 97struct altera_pcie_ops {
 98	int (*tlp_read_pkt)(struct altera_pcie *pcie, u32 *value);
 99	void (*tlp_write_pkt)(struct altera_pcie *pcie, u32 *headers,
100			      u32 data, bool align);
101	bool (*get_link_status)(struct altera_pcie *pcie);
102	int (*rp_read_cfg)(struct altera_pcie *pcie, int where,
103			   int size, u32 *value);
104	int (*rp_write_cfg)(struct altera_pcie *pcie, u8 busno,
105			    int where, int size, u32 value);
106};
107
108struct altera_pcie_data {
109	const struct altera_pcie_ops *ops;
110	enum altera_pcie_version version;
111	u32 cap_offset;		/* PCIe capability structure register offset */
112	u32 cfgrd0;
113	u32 cfgrd1;
114	u32 cfgwr0;
115	u32 cfgwr1;
116};
117
118struct tlp_rp_regpair_t {
119	u32 ctrl;
120	u32 reg0;
121	u32 reg1;
122};
123
124static inline void cra_writel(struct altera_pcie *pcie, const u32 value,
125			      const u32 reg)
126{
127	writel_relaxed(value, pcie->cra_base + reg);
128}
129
130static inline u32 cra_readl(struct altera_pcie *pcie, const u32 reg)
131{
132	return readl_relaxed(pcie->cra_base + reg);
133}
134
135static bool altera_pcie_link_up(struct altera_pcie *pcie)
136{
137	return !!((cra_readl(pcie, RP_LTSSM) & RP_LTSSM_MASK) == LTSSM_L0);
138}
139
140static bool s10_altera_pcie_link_up(struct altera_pcie *pcie)
141{
142	void __iomem *addr = S10_RP_CFG_ADDR(pcie,
143				   pcie->pcie_data->cap_offset +
144				   PCI_EXP_LNKSTA);
145
146	return !!(readw(addr) & PCI_EXP_LNKSTA_DLLLA);
147}
148
149/*
150 * Altera PCIe port uses BAR0 of RC's configuration space as the translation
151 * from PCI bus to native BUS.  Entire DDR region is mapped into PCIe space
152 * using these registers, so it can be reached by DMA from EP devices.
153 * This BAR0 will also access to MSI vector when receiving MSI/MSIX interrupt
154 * from EP devices, eventually trigger interrupt to GIC.  The BAR0 of bridge
155 * should be hidden during enumeration to avoid the sizing and resource
156 * allocation by PCIe core.
157 */
158static bool altera_pcie_hide_rc_bar(struct pci_bus *bus, unsigned int  devfn,
159				    int offset)
160{
161	if (pci_is_root_bus(bus) && (devfn == 0) &&
162	    (offset == PCI_BASE_ADDRESS_0))
163		return true;
164
165	return false;
166}
167
168static void tlp_write_tx(struct altera_pcie *pcie,
169			 struct tlp_rp_regpair_t *tlp_rp_regdata)
170{
171	cra_writel(pcie, tlp_rp_regdata->reg0, RP_TX_REG0);
172	cra_writel(pcie, tlp_rp_regdata->reg1, RP_TX_REG1);
173	cra_writel(pcie, tlp_rp_regdata->ctrl, RP_TX_CNTRL);
174}
175
176static void s10_tlp_write_tx(struct altera_pcie *pcie, u32 reg0, u32 ctrl)
177{
178	cra_writel(pcie, reg0, RP_TX_REG0);
179	cra_writel(pcie, ctrl, S10_RP_TX_CNTRL);
180}
181
182static bool altera_pcie_valid_device(struct altera_pcie *pcie,
183				     struct pci_bus *bus, int dev)
184{
185	/* If there is no link, then there is no device */
186	if (bus->number != pcie->root_bus_nr) {
187		if (!pcie->pcie_data->ops->get_link_status(pcie))
188			return false;
189	}
190
191	/* access only one slot on each root port */
192	if (bus->number == pcie->root_bus_nr && dev > 0)
193		return false;
194
195	return true;
196}
197
198static int tlp_read_packet(struct altera_pcie *pcie, u32 *value)
199{
200	int i;
201	bool sop = false;
202	u32 ctrl;
203	u32 reg0, reg1;
204	u32 comp_status = 1;
205
206	/*
207	 * Minimum 2 loops to read TLP headers and 1 loop to read data
208	 * payload.
209	 */
210	for (i = 0; i < TLP_LOOP; i++) {
211		ctrl = cra_readl(pcie, RP_RXCPL_STATUS);
212		if ((ctrl & RP_RXCPL_SOP) || (ctrl & RP_RXCPL_EOP) || sop) {
213			reg0 = cra_readl(pcie, RP_RXCPL_REG0);
214			reg1 = cra_readl(pcie, RP_RXCPL_REG1);
215
216			if (ctrl & RP_RXCPL_SOP) {
217				sop = true;
218				comp_status = TLP_COMP_STATUS(reg1);
219			}
220
221			if (ctrl & RP_RXCPL_EOP) {
222				if (comp_status)
223					return PCIBIOS_DEVICE_NOT_FOUND;
224
225				if (value)
226					*value = reg0;
227
228				return PCIBIOS_SUCCESSFUL;
229			}
230		}
231		udelay(5);
232	}
233
234	return PCIBIOS_DEVICE_NOT_FOUND;
235}
236
237static int s10_tlp_read_packet(struct altera_pcie *pcie, u32 *value)
238{
239	u32 ctrl;
240	u32 comp_status;
241	u32 dw[4];
242	u32 count;
243	struct device *dev = &pcie->pdev->dev;
244
245	for (count = 0; count < TLP_LOOP; count++) {
246		ctrl = cra_readl(pcie, S10_RP_RXCPL_STATUS);
247		if (ctrl & RP_RXCPL_SOP) {
248			/* Read first DW */
249			dw[0] = cra_readl(pcie, S10_RP_RXCPL_REG);
250			break;
251		}
252
253		udelay(5);
254	}
255
256	/* SOP detection failed, return error */
257	if (count == TLP_LOOP)
258		return PCIBIOS_DEVICE_NOT_FOUND;
259
260	count = 1;
261
262	/* Poll for EOP */
263	while (count < ARRAY_SIZE(dw)) {
264		ctrl = cra_readl(pcie, S10_RP_RXCPL_STATUS);
265		dw[count++] = cra_readl(pcie, S10_RP_RXCPL_REG);
266		if (ctrl & RP_RXCPL_EOP) {
267			comp_status = TLP_COMP_STATUS(dw[1]);
268			if (comp_status)
269				return PCIBIOS_DEVICE_NOT_FOUND;
270
271			if (value && TLP_BYTE_COUNT(dw[1]) == sizeof(u32) &&
272			    count == 4)
273				*value = dw[3];
274
275			return PCIBIOS_SUCCESSFUL;
276		}
277	}
278
279	dev_warn(dev, "Malformed TLP packet\n");
280
281	return PCIBIOS_DEVICE_NOT_FOUND;
282}
283
284static void tlp_write_packet(struct altera_pcie *pcie, u32 *headers,
285			     u32 data, bool align)
286{
287	struct tlp_rp_regpair_t tlp_rp_regdata;
288
289	tlp_rp_regdata.reg0 = headers[0];
290	tlp_rp_regdata.reg1 = headers[1];
291	tlp_rp_regdata.ctrl = RP_TX_SOP;
292	tlp_write_tx(pcie, &tlp_rp_regdata);
293
294	if (align) {
295		tlp_rp_regdata.reg0 = headers[2];
296		tlp_rp_regdata.reg1 = 0;
297		tlp_rp_regdata.ctrl = 0;
298		tlp_write_tx(pcie, &tlp_rp_regdata);
299
300		tlp_rp_regdata.reg0 = data;
301		tlp_rp_regdata.reg1 = 0;
302	} else {
303		tlp_rp_regdata.reg0 = headers[2];
304		tlp_rp_regdata.reg1 = data;
305	}
306
307	tlp_rp_regdata.ctrl = RP_TX_EOP;
308	tlp_write_tx(pcie, &tlp_rp_regdata);
309}
310
311static void s10_tlp_write_packet(struct altera_pcie *pcie, u32 *headers,
312				 u32 data, bool dummy)
313{
314	s10_tlp_write_tx(pcie, headers[0], RP_TX_SOP);
315	s10_tlp_write_tx(pcie, headers[1], 0);
316	s10_tlp_write_tx(pcie, headers[2], 0);
317	s10_tlp_write_tx(pcie, data, RP_TX_EOP);
318}
319
320static void get_tlp_header(struct altera_pcie *pcie, u8 bus, u32 devfn,
321			   int where, u8 byte_en, bool read, u32 *headers)
322{
323	u8 cfg;
324	u8 cfg0 = read ? pcie->pcie_data->cfgrd0 : pcie->pcie_data->cfgwr0;
325	u8 cfg1 = read ? pcie->pcie_data->cfgrd1 : pcie->pcie_data->cfgwr1;
326	u8 tag = read ? TLP_READ_TAG : TLP_WRITE_TAG;
327
328	if (pcie->pcie_data->version == ALTERA_PCIE_V1)
329		cfg = (bus == pcie->root_bus_nr) ? cfg0 : cfg1;
330	else
331		cfg = (bus > S10_RP_SECONDARY(pcie)) ? cfg0 : cfg1;
332
333	headers[0] = TLP_CFG_DW0(pcie, cfg);
334	headers[1] = TLP_CFG_DW1(pcie, tag, byte_en);
335	headers[2] = TLP_CFG_DW2(bus, devfn, where);
336}
337
338static int tlp_cfg_dword_read(struct altera_pcie *pcie, u8 bus, u32 devfn,
339			      int where, u8 byte_en, u32 *value)
340{
341	u32 headers[TLP_HDR_SIZE];
342
343	get_tlp_header(pcie, bus, devfn, where, byte_en, true,
344		       headers);
345
346	pcie->pcie_data->ops->tlp_write_pkt(pcie, headers, 0, false);
347
348	return pcie->pcie_data->ops->tlp_read_pkt(pcie, value);
349}
350
351static int tlp_cfg_dword_write(struct altera_pcie *pcie, u8 bus, u32 devfn,
352			       int where, u8 byte_en, u32 value)
353{
354	u32 headers[TLP_HDR_SIZE];
355	int ret;
356
357	get_tlp_header(pcie, bus, devfn, where, byte_en, false,
358		       headers);
359
360	/* check alignment to Qword */
361	if ((where & 0x7) == 0)
362		pcie->pcie_data->ops->tlp_write_pkt(pcie, headers,
363						    value, true);
364	else
365		pcie->pcie_data->ops->tlp_write_pkt(pcie, headers,
366						    value, false);
367
368	ret = pcie->pcie_data->ops->tlp_read_pkt(pcie, NULL);
369	if (ret != PCIBIOS_SUCCESSFUL)
370		return ret;
371
372	/*
373	 * Monitor changes to PCI_PRIMARY_BUS register on root port
374	 * and update local copy of root bus number accordingly.
375	 */
376	if ((bus == pcie->root_bus_nr) && (where == PCI_PRIMARY_BUS))
377		pcie->root_bus_nr = (u8)(value);
378
379	return PCIBIOS_SUCCESSFUL;
380}
381
382static int s10_rp_read_cfg(struct altera_pcie *pcie, int where,
383			   int size, u32 *value)
384{
385	void __iomem *addr = S10_RP_CFG_ADDR(pcie, where);
386
387	switch (size) {
388	case 1:
389		*value = readb(addr);
390		break;
391	case 2:
392		*value = readw(addr);
393		break;
394	default:
395		*value = readl(addr);
396		break;
397	}
398
399	return PCIBIOS_SUCCESSFUL;
400}
401
402static int s10_rp_write_cfg(struct altera_pcie *pcie, u8 busno,
403			    int where, int size, u32 value)
404{
405	void __iomem *addr = S10_RP_CFG_ADDR(pcie, where);
406
407	switch (size) {
408	case 1:
409		writeb(value, addr);
410		break;
411	case 2:
412		writew(value, addr);
413		break;
414	default:
415		writel(value, addr);
416		break;
417	}
418
419	/*
420	 * Monitor changes to PCI_PRIMARY_BUS register on root port
421	 * and update local copy of root bus number accordingly.
422	 */
423	if (busno == pcie->root_bus_nr && where == PCI_PRIMARY_BUS)
424		pcie->root_bus_nr = value & 0xff;
425
426	return PCIBIOS_SUCCESSFUL;
427}
428
429static int _altera_pcie_cfg_read(struct altera_pcie *pcie, u8 busno,
430				 unsigned int devfn, int where, int size,
431				 u32 *value)
432{
433	int ret;
434	u32 data;
435	u8 byte_en;
436
437	if (busno == pcie->root_bus_nr && pcie->pcie_data->ops->rp_read_cfg)
438		return pcie->pcie_data->ops->rp_read_cfg(pcie, where,
439							 size, value);
440
441	switch (size) {
442	case 1:
443		byte_en = 1 << (where & 3);
444		break;
445	case 2:
446		byte_en = 3 << (where & 3);
447		break;
448	default:
449		byte_en = 0xf;
450		break;
451	}
452
453	ret = tlp_cfg_dword_read(pcie, busno, devfn,
454				 (where & ~DWORD_MASK), byte_en, &data);
455	if (ret != PCIBIOS_SUCCESSFUL)
456		return ret;
457
458	switch (size) {
459	case 1:
460		*value = (data >> (8 * (where & 0x3))) & 0xff;
461		break;
462	case 2:
463		*value = (data >> (8 * (where & 0x2))) & 0xffff;
464		break;
465	default:
466		*value = data;
467		break;
468	}
469
470	return PCIBIOS_SUCCESSFUL;
471}
472
473static int _altera_pcie_cfg_write(struct altera_pcie *pcie, u8 busno,
474				  unsigned int devfn, int where, int size,
475				  u32 value)
476{
477	u32 data32;
478	u32 shift = 8 * (where & 3);
479	u8 byte_en;
480
481	if (busno == pcie->root_bus_nr && pcie->pcie_data->ops->rp_write_cfg)
482		return pcie->pcie_data->ops->rp_write_cfg(pcie, busno,
483						     where, size, value);
484
485	switch (size) {
486	case 1:
487		data32 = (value & 0xff) << shift;
488		byte_en = 1 << (where & 3);
489		break;
490	case 2:
491		data32 = (value & 0xffff) << shift;
492		byte_en = 3 << (where & 3);
493		break;
494	default:
495		data32 = value;
496		byte_en = 0xf;
497		break;
498	}
499
500	return tlp_cfg_dword_write(pcie, busno, devfn, (where & ~DWORD_MASK),
501				   byte_en, data32);
502}
503
504static int altera_pcie_cfg_read(struct pci_bus *bus, unsigned int devfn,
505				int where, int size, u32 *value)
506{
507	struct altera_pcie *pcie = bus->sysdata;
508
509	if (altera_pcie_hide_rc_bar(bus, devfn, where))
510		return PCIBIOS_BAD_REGISTER_NUMBER;
511
512	if (!altera_pcie_valid_device(pcie, bus, PCI_SLOT(devfn)))
 
513		return PCIBIOS_DEVICE_NOT_FOUND;
 
514
515	return _altera_pcie_cfg_read(pcie, bus->number, devfn, where, size,
516				     value);
517}
518
519static int altera_pcie_cfg_write(struct pci_bus *bus, unsigned int devfn,
520				 int where, int size, u32 value)
521{
522	struct altera_pcie *pcie = bus->sysdata;
523
524	if (altera_pcie_hide_rc_bar(bus, devfn, where))
525		return PCIBIOS_BAD_REGISTER_NUMBER;
526
527	if (!altera_pcie_valid_device(pcie, bus, PCI_SLOT(devfn)))
528		return PCIBIOS_DEVICE_NOT_FOUND;
529
530	return _altera_pcie_cfg_write(pcie, bus->number, devfn, where, size,
531				     value);
532}
533
534static struct pci_ops altera_pcie_ops = {
535	.read = altera_pcie_cfg_read,
536	.write = altera_pcie_cfg_write,
537};
538
539static int altera_read_cap_word(struct altera_pcie *pcie, u8 busno,
540				unsigned int devfn, int offset, u16 *value)
541{
542	u32 data;
543	int ret;
544
545	ret = _altera_pcie_cfg_read(pcie, busno, devfn,
546				    pcie->pcie_data->cap_offset + offset,
547				    sizeof(*value),
548				    &data);
549	*value = data;
550	return ret;
551}
552
553static int altera_write_cap_word(struct altera_pcie *pcie, u8 busno,
554				 unsigned int devfn, int offset, u16 value)
555{
556	return _altera_pcie_cfg_write(pcie, busno, devfn,
557				      pcie->pcie_data->cap_offset + offset,
558				      sizeof(value),
559				      value);
560}
561
562static void altera_wait_link_retrain(struct altera_pcie *pcie)
563{
564	struct device *dev = &pcie->pdev->dev;
565	u16 reg16;
566	unsigned long start_jiffies;
567
568	/* Wait for link training end. */
569	start_jiffies = jiffies;
570	for (;;) {
571		altera_read_cap_word(pcie, pcie->root_bus_nr, RP_DEVFN,
572				     PCI_EXP_LNKSTA, &reg16);
573		if (!(reg16 & PCI_EXP_LNKSTA_LT))
574			break;
575
576		if (time_after(jiffies, start_jiffies + LINK_RETRAIN_TIMEOUT)) {
577			dev_err(dev, "link retrain timeout\n");
578			break;
579		}
580		udelay(100);
581	}
582
583	/* Wait for link is up */
584	start_jiffies = jiffies;
585	for (;;) {
586		if (pcie->pcie_data->ops->get_link_status(pcie))
587			break;
588
589		if (time_after(jiffies, start_jiffies + LINK_UP_TIMEOUT)) {
590			dev_err(dev, "link up timeout\n");
591			break;
592		}
593		udelay(100);
594	}
595}
596
597static void altera_pcie_retrain(struct altera_pcie *pcie)
598{
599	u16 linkcap, linkstat, linkctl;
600
601	if (!pcie->pcie_data->ops->get_link_status(pcie))
602		return;
603
604	/*
605	 * Set the retrain bit if the PCIe rootport support > 2.5GB/s, but
606	 * current speed is 2.5 GB/s.
607	 */
608	altera_read_cap_word(pcie, pcie->root_bus_nr, RP_DEVFN, PCI_EXP_LNKCAP,
609			     &linkcap);
610	if ((linkcap & PCI_EXP_LNKCAP_SLS) <= PCI_EXP_LNKCAP_SLS_2_5GB)
611		return;
612
613	altera_read_cap_word(pcie, pcie->root_bus_nr, RP_DEVFN, PCI_EXP_LNKSTA,
614			     &linkstat);
615	if ((linkstat & PCI_EXP_LNKSTA_CLS) == PCI_EXP_LNKSTA_CLS_2_5GB) {
616		altera_read_cap_word(pcie, pcie->root_bus_nr, RP_DEVFN,
617				     PCI_EXP_LNKCTL, &linkctl);
618		linkctl |= PCI_EXP_LNKCTL_RL;
619		altera_write_cap_word(pcie, pcie->root_bus_nr, RP_DEVFN,
620				      PCI_EXP_LNKCTL, linkctl);
621
622		altera_wait_link_retrain(pcie);
623	}
624}
625
626static int altera_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
627				irq_hw_number_t hwirq)
628{
629	irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_simple_irq);
630	irq_set_chip_data(irq, domain->host_data);
631	return 0;
632}
633
634static const struct irq_domain_ops intx_domain_ops = {
635	.map = altera_pcie_intx_map,
636	.xlate = pci_irqd_intx_xlate,
637};
638
639static void altera_pcie_isr(struct irq_desc *desc)
640{
641	struct irq_chip *chip = irq_desc_get_chip(desc);
642	struct altera_pcie *pcie;
643	struct device *dev;
644	unsigned long status;
645	u32 bit;
646	int ret;
647
648	chained_irq_enter(chip, desc);
649	pcie = irq_desc_get_handler_data(desc);
650	dev = &pcie->pdev->dev;
651
652	while ((status = cra_readl(pcie, P2A_INT_STATUS)
653		& P2A_INT_STS_ALL) != 0) {
654		for_each_set_bit(bit, &status, PCI_NUM_INTX) {
655			/* clear interrupts */
656			cra_writel(pcie, 1 << bit, P2A_INT_STATUS);
657
658			ret = generic_handle_domain_irq(pcie->irq_domain, bit);
659			if (ret)
660				dev_err_ratelimited(dev, "unexpected IRQ, INT%d\n", bit);
 
 
661		}
662	}
663
664	chained_irq_exit(chip, desc);
665}
666
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
667static int altera_pcie_init_irq_domain(struct altera_pcie *pcie)
668{
669	struct device *dev = &pcie->pdev->dev;
670	struct device_node *node = dev->of_node;
671
672	/* Setup INTx */
673	pcie->irq_domain = irq_domain_add_linear(node, PCI_NUM_INTX,
674					&intx_domain_ops, pcie);
675	if (!pcie->irq_domain) {
676		dev_err(dev, "Failed to get a INTx IRQ domain\n");
677		return -ENOMEM;
678	}
679
680	return 0;
681}
682
683static void altera_pcie_irq_teardown(struct altera_pcie *pcie)
684{
685	irq_set_chained_handler_and_data(pcie->irq, NULL, NULL);
686	irq_domain_remove(pcie->irq_domain);
687	irq_dispose_mapping(pcie->irq);
688}
689
690static int altera_pcie_parse_dt(struct altera_pcie *pcie)
691{
 
692	struct platform_device *pdev = pcie->pdev;
 
 
693
694	pcie->cra_base = devm_platform_ioremap_resource_byname(pdev, "Cra");
 
695	if (IS_ERR(pcie->cra_base))
696		return PTR_ERR(pcie->cra_base);
697
698	if (pcie->pcie_data->version == ALTERA_PCIE_V2) {
699		pcie->hip_base =
700			devm_platform_ioremap_resource_byname(pdev, "Hip");
701		if (IS_ERR(pcie->hip_base))
702			return PTR_ERR(pcie->hip_base);
703	}
704
705	/* setup IRQ */
706	pcie->irq = platform_get_irq(pdev, 0);
707	if (pcie->irq < 0)
 
708		return pcie->irq;
 
709
710	irq_set_chained_handler_and_data(pcie->irq, altera_pcie_isr, pcie);
711	return 0;
712}
713
714static void altera_pcie_host_init(struct altera_pcie *pcie)
715{
716	altera_pcie_retrain(pcie);
717}
718
719static const struct altera_pcie_ops altera_pcie_ops_1_0 = {
720	.tlp_read_pkt = tlp_read_packet,
721	.tlp_write_pkt = tlp_write_packet,
722	.get_link_status = altera_pcie_link_up,
723};
724
725static const struct altera_pcie_ops altera_pcie_ops_2_0 = {
726	.tlp_read_pkt = s10_tlp_read_packet,
727	.tlp_write_pkt = s10_tlp_write_packet,
728	.get_link_status = s10_altera_pcie_link_up,
729	.rp_read_cfg = s10_rp_read_cfg,
730	.rp_write_cfg = s10_rp_write_cfg,
731};
732
733static const struct altera_pcie_data altera_pcie_1_0_data = {
734	.ops = &altera_pcie_ops_1_0,
735	.cap_offset = 0x80,
736	.version = ALTERA_PCIE_V1,
737	.cfgrd0 = TLP_FMTTYPE_CFGRD0,
738	.cfgrd1 = TLP_FMTTYPE_CFGRD1,
739	.cfgwr0 = TLP_FMTTYPE_CFGWR0,
740	.cfgwr1 = TLP_FMTTYPE_CFGWR1,
741};
742
743static const struct altera_pcie_data altera_pcie_2_0_data = {
744	.ops = &altera_pcie_ops_2_0,
745	.version = ALTERA_PCIE_V2,
746	.cap_offset = 0x70,
747	.cfgrd0 = S10_TLP_FMTTYPE_CFGRD0,
748	.cfgrd1 = S10_TLP_FMTTYPE_CFGRD1,
749	.cfgwr0 = S10_TLP_FMTTYPE_CFGWR0,
750	.cfgwr1 = S10_TLP_FMTTYPE_CFGWR1,
751};
752
753static const struct of_device_id altera_pcie_of_match[] = {
754	{.compatible = "altr,pcie-root-port-1.0",
755	 .data = &altera_pcie_1_0_data },
756	{.compatible = "altr,pcie-root-port-2.0",
757	 .data = &altera_pcie_2_0_data },
758	{},
759};
760
761static int altera_pcie_probe(struct platform_device *pdev)
762{
763	struct device *dev = &pdev->dev;
764	struct altera_pcie *pcie;
 
 
765	struct pci_host_bridge *bridge;
766	int ret;
767	const struct altera_pcie_data *data;
768
769	bridge = devm_pci_alloc_host_bridge(dev, sizeof(*pcie));
770	if (!bridge)
771		return -ENOMEM;
772
773	pcie = pci_host_bridge_priv(bridge);
774	pcie->pdev = pdev;
775	platform_set_drvdata(pdev, pcie);
776
777	data = of_device_get_match_data(&pdev->dev);
778	if (!data)
779		return -ENODEV;
780
781	pcie->pcie_data = data;
782
783	ret = altera_pcie_parse_dt(pcie);
784	if (ret) {
785		dev_err(dev, "Parsing DT failed\n");
786		return ret;
787	}
788
 
 
 
 
 
 
 
 
789	ret = altera_pcie_init_irq_domain(pcie);
790	if (ret) {
791		dev_err(dev, "Failed creating IRQ Domain\n");
792		return ret;
793	}
794
795	/* clear all interrupts */
796	cra_writel(pcie, P2A_INT_STS_ALL, P2A_INT_STATUS);
797	/* enable all interrupts */
798	cra_writel(pcie, P2A_INT_ENA_ALL, P2A_INT_ENABLE);
799	altera_pcie_host_init(pcie);
800
 
 
801	bridge->sysdata = pcie;
802	bridge->busnr = pcie->root_bus_nr;
803	bridge->ops = &altera_pcie_ops;
 
 
804
805	return pci_host_probe(bridge);
 
 
 
 
 
 
 
 
 
 
 
 
 
806}
807
808static void altera_pcie_remove(struct platform_device *pdev)
809{
810	struct altera_pcie *pcie = platform_get_drvdata(pdev);
811	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
812
813	pci_stop_root_bus(bridge->bus);
814	pci_remove_root_bus(bridge->bus);
 
815	altera_pcie_irq_teardown(pcie);
 
 
816}
817
818static struct platform_driver altera_pcie_driver = {
819	.probe		= altera_pcie_probe,
820	.remove_new	= altera_pcie_remove,
821	.driver = {
822		.name	= "altera-pcie",
823		.of_match_table = altera_pcie_of_match,
824	},
825};
826
827MODULE_DEVICE_TABLE(of, altera_pcie_of_match);
828module_platform_driver(altera_pcie_driver);
829MODULE_LICENSE("GPL v2");
v5.4
  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/init.h>
 13#include <linux/module.h>
 14#include <linux/of_address.h>
 15#include <linux/of_device.h>
 16#include <linux/of_irq.h>
 17#include <linux/of_pci.h>
 18#include <linux/pci.h>
 19#include <linux/platform_device.h>
 20#include <linux/slab.h>
 21
 22#include "../pci.h"
 23
 24#define RP_TX_REG0			0x2000
 25#define RP_TX_REG1			0x2004
 26#define RP_TX_CNTRL			0x2008
 27#define RP_TX_EOP			0x2
 28#define RP_TX_SOP			0x1
 29#define RP_RXCPL_STATUS			0x2010
 30#define RP_RXCPL_EOP			0x2
 31#define RP_RXCPL_SOP			0x1
 32#define RP_RXCPL_REG0			0x2014
 33#define RP_RXCPL_REG1			0x2018
 34#define P2A_INT_STATUS			0x3060
 35#define P2A_INT_STS_ALL			0xf
 36#define P2A_INT_ENABLE			0x3070
 37#define P2A_INT_ENA_ALL			0xf
 38#define RP_LTSSM			0x3c64
 39#define RP_LTSSM_MASK			0x1f
 40#define LTSSM_L0			0xf
 41
 42#define S10_RP_TX_CNTRL			0x2004
 43#define S10_RP_RXCPL_REG		0x2008
 44#define S10_RP_RXCPL_STATUS		0x200C
 45#define S10_RP_CFG_ADDR(pcie, reg)	\
 46	(((pcie)->hip_base) + (reg) + (1 << 20))
 47#define S10_RP_SECONDARY(pcie)		\
 48	readb(S10_RP_CFG_ADDR(pcie, PCI_SECONDARY_BUS))
 49
 50/* TLP configuration type 0 and 1 */
 51#define TLP_FMTTYPE_CFGRD0		0x04	/* Configuration Read Type 0 */
 52#define TLP_FMTTYPE_CFGWR0		0x44	/* Configuration Write Type 0 */
 53#define TLP_FMTTYPE_CFGRD1		0x05	/* Configuration Read Type 1 */
 54#define TLP_FMTTYPE_CFGWR1		0x45	/* Configuration Write Type 1 */
 55#define TLP_PAYLOAD_SIZE		0x01
 56#define TLP_READ_TAG			0x1d
 57#define TLP_WRITE_TAG			0x10
 58#define RP_DEVFN			0
 59#define TLP_REQ_ID(bus, devfn)		(((bus) << 8) | (devfn))
 60#define TLP_CFG_DW0(pcie, cfg)		\
 61		(((cfg) << 24) |	\
 62		  TLP_PAYLOAD_SIZE)
 63#define TLP_CFG_DW1(pcie, tag, be)	\
 64	(((TLP_REQ_ID(pcie->root_bus_nr,  RP_DEVFN)) << 16) | (tag << 8) | (be))
 65#define TLP_CFG_DW2(bus, devfn, offset)	\
 66				(((bus) << 24) | ((devfn) << 16) | (offset))
 67#define TLP_COMP_STATUS(s)		(((s) >> 13) & 7)
 68#define TLP_BYTE_COUNT(s)		(((s) >> 0) & 0xfff)
 69#define TLP_HDR_SIZE			3
 70#define TLP_LOOP			500
 71
 72#define LINK_UP_TIMEOUT			HZ
 73#define LINK_RETRAIN_TIMEOUT		HZ
 74
 75#define DWORD_MASK			3
 76
 77#define S10_TLP_FMTTYPE_CFGRD0		0x05
 78#define S10_TLP_FMTTYPE_CFGRD1		0x04
 79#define S10_TLP_FMTTYPE_CFGWR0		0x45
 80#define S10_TLP_FMTTYPE_CFGWR1		0x44
 81
 82enum altera_pcie_version {
 83	ALTERA_PCIE_V1 = 0,
 84	ALTERA_PCIE_V2,
 85};
 86
 87struct altera_pcie {
 88	struct platform_device	*pdev;
 89	void __iomem		*cra_base;
 90	void __iomem		*hip_base;
 91	int			irq;
 92	u8			root_bus_nr;
 93	struct irq_domain	*irq_domain;
 94	struct resource		bus_range;
 95	struct list_head	resources;
 96	const struct altera_pcie_data	*pcie_data;
 97};
 98
 99struct altera_pcie_ops {
100	int (*tlp_read_pkt)(struct altera_pcie *pcie, u32 *value);
101	void (*tlp_write_pkt)(struct altera_pcie *pcie, u32 *headers,
102			      u32 data, bool align);
103	bool (*get_link_status)(struct altera_pcie *pcie);
104	int (*rp_read_cfg)(struct altera_pcie *pcie, int where,
105			   int size, u32 *value);
106	int (*rp_write_cfg)(struct altera_pcie *pcie, u8 busno,
107			    int where, int size, u32 value);
108};
109
110struct altera_pcie_data {
111	const struct altera_pcie_ops *ops;
112	enum altera_pcie_version version;
113	u32 cap_offset;		/* PCIe capability structure register offset */
114	u32 cfgrd0;
115	u32 cfgrd1;
116	u32 cfgwr0;
117	u32 cfgwr1;
118};
119
120struct tlp_rp_regpair_t {
121	u32 ctrl;
122	u32 reg0;
123	u32 reg1;
124};
125
126static inline void cra_writel(struct altera_pcie *pcie, const u32 value,
127			      const u32 reg)
128{
129	writel_relaxed(value, pcie->cra_base + reg);
130}
131
132static inline u32 cra_readl(struct altera_pcie *pcie, const u32 reg)
133{
134	return readl_relaxed(pcie->cra_base + reg);
135}
136
137static bool altera_pcie_link_up(struct altera_pcie *pcie)
138{
139	return !!((cra_readl(pcie, RP_LTSSM) & RP_LTSSM_MASK) == LTSSM_L0);
140}
141
142static bool s10_altera_pcie_link_up(struct altera_pcie *pcie)
143{
144	void __iomem *addr = S10_RP_CFG_ADDR(pcie,
145				   pcie->pcie_data->cap_offset +
146				   PCI_EXP_LNKSTA);
147
148	return !!(readw(addr) & PCI_EXP_LNKSTA_DLLLA);
149}
150
151/*
152 * Altera PCIe port uses BAR0 of RC's configuration space as the translation
153 * from PCI bus to native BUS.  Entire DDR region is mapped into PCIe space
154 * using these registers, so it can be reached by DMA from EP devices.
155 * This BAR0 will also access to MSI vector when receiving MSI/MSIX interrupt
156 * from EP devices, eventually trigger interrupt to GIC.  The BAR0 of bridge
157 * should be hidden during enumeration to avoid the sizing and resource
158 * allocation by PCIe core.
159 */
160static bool altera_pcie_hide_rc_bar(struct pci_bus *bus, unsigned int  devfn,
161				    int offset)
162{
163	if (pci_is_root_bus(bus) && (devfn == 0) &&
164	    (offset == PCI_BASE_ADDRESS_0))
165		return true;
166
167	return false;
168}
169
170static void tlp_write_tx(struct altera_pcie *pcie,
171			 struct tlp_rp_regpair_t *tlp_rp_regdata)
172{
173	cra_writel(pcie, tlp_rp_regdata->reg0, RP_TX_REG0);
174	cra_writel(pcie, tlp_rp_regdata->reg1, RP_TX_REG1);
175	cra_writel(pcie, tlp_rp_regdata->ctrl, RP_TX_CNTRL);
176}
177
178static void s10_tlp_write_tx(struct altera_pcie *pcie, u32 reg0, u32 ctrl)
179{
180	cra_writel(pcie, reg0, RP_TX_REG0);
181	cra_writel(pcie, ctrl, S10_RP_TX_CNTRL);
182}
183
184static bool altera_pcie_valid_device(struct altera_pcie *pcie,
185				     struct pci_bus *bus, int dev)
186{
187	/* If there is no link, then there is no device */
188	if (bus->number != pcie->root_bus_nr) {
189		if (!pcie->pcie_data->ops->get_link_status(pcie))
190			return false;
191	}
192
193	/* access only one slot on each root port */
194	if (bus->number == pcie->root_bus_nr && dev > 0)
195		return false;
196
197	 return true;
198}
199
200static int tlp_read_packet(struct altera_pcie *pcie, u32 *value)
201{
202	int i;
203	bool sop = false;
204	u32 ctrl;
205	u32 reg0, reg1;
206	u32 comp_status = 1;
207
208	/*
209	 * Minimum 2 loops to read TLP headers and 1 loop to read data
210	 * payload.
211	 */
212	for (i = 0; i < TLP_LOOP; i++) {
213		ctrl = cra_readl(pcie, RP_RXCPL_STATUS);
214		if ((ctrl & RP_RXCPL_SOP) || (ctrl & RP_RXCPL_EOP) || sop) {
215			reg0 = cra_readl(pcie, RP_RXCPL_REG0);
216			reg1 = cra_readl(pcie, RP_RXCPL_REG1);
217
218			if (ctrl & RP_RXCPL_SOP) {
219				sop = true;
220				comp_status = TLP_COMP_STATUS(reg1);
221			}
222
223			if (ctrl & RP_RXCPL_EOP) {
224				if (comp_status)
225					return PCIBIOS_DEVICE_NOT_FOUND;
226
227				if (value)
228					*value = reg0;
229
230				return PCIBIOS_SUCCESSFUL;
231			}
232		}
233		udelay(5);
234	}
235
236	return PCIBIOS_DEVICE_NOT_FOUND;
237}
238
239static int s10_tlp_read_packet(struct altera_pcie *pcie, u32 *value)
240{
241	u32 ctrl;
242	u32 comp_status;
243	u32 dw[4];
244	u32 count;
245	struct device *dev = &pcie->pdev->dev;
246
247	for (count = 0; count < TLP_LOOP; count++) {
248		ctrl = cra_readl(pcie, S10_RP_RXCPL_STATUS);
249		if (ctrl & RP_RXCPL_SOP) {
250			/* Read first DW */
251			dw[0] = cra_readl(pcie, S10_RP_RXCPL_REG);
252			break;
253		}
254
255		udelay(5);
256	}
257
258	/* SOP detection failed, return error */
259	if (count == TLP_LOOP)
260		return PCIBIOS_DEVICE_NOT_FOUND;
261
262	count = 1;
263
264	/* Poll for EOP */
265	while (count < ARRAY_SIZE(dw)) {
266		ctrl = cra_readl(pcie, S10_RP_RXCPL_STATUS);
267		dw[count++] = cra_readl(pcie, S10_RP_RXCPL_REG);
268		if (ctrl & RP_RXCPL_EOP) {
269			comp_status = TLP_COMP_STATUS(dw[1]);
270			if (comp_status)
271				return PCIBIOS_DEVICE_NOT_FOUND;
272
273			if (value && TLP_BYTE_COUNT(dw[1]) == sizeof(u32) &&
274			    count == 4)
275				*value = dw[3];
276
277			return PCIBIOS_SUCCESSFUL;
278		}
279	}
280
281	dev_warn(dev, "Malformed TLP packet\n");
282
283	return PCIBIOS_DEVICE_NOT_FOUND;
284}
285
286static void tlp_write_packet(struct altera_pcie *pcie, u32 *headers,
287			     u32 data, bool align)
288{
289	struct tlp_rp_regpair_t tlp_rp_regdata;
290
291	tlp_rp_regdata.reg0 = headers[0];
292	tlp_rp_regdata.reg1 = headers[1];
293	tlp_rp_regdata.ctrl = RP_TX_SOP;
294	tlp_write_tx(pcie, &tlp_rp_regdata);
295
296	if (align) {
297		tlp_rp_regdata.reg0 = headers[2];
298		tlp_rp_regdata.reg1 = 0;
299		tlp_rp_regdata.ctrl = 0;
300		tlp_write_tx(pcie, &tlp_rp_regdata);
301
302		tlp_rp_regdata.reg0 = data;
303		tlp_rp_regdata.reg1 = 0;
304	} else {
305		tlp_rp_regdata.reg0 = headers[2];
306		tlp_rp_regdata.reg1 = data;
307	}
308
309	tlp_rp_regdata.ctrl = RP_TX_EOP;
310	tlp_write_tx(pcie, &tlp_rp_regdata);
311}
312
313static void s10_tlp_write_packet(struct altera_pcie *pcie, u32 *headers,
314				 u32 data, bool dummy)
315{
316	s10_tlp_write_tx(pcie, headers[0], RP_TX_SOP);
317	s10_tlp_write_tx(pcie, headers[1], 0);
318	s10_tlp_write_tx(pcie, headers[2], 0);
319	s10_tlp_write_tx(pcie, data, RP_TX_EOP);
320}
321
322static void get_tlp_header(struct altera_pcie *pcie, u8 bus, u32 devfn,
323			   int where, u8 byte_en, bool read, u32 *headers)
324{
325	u8 cfg;
326	u8 cfg0 = read ? pcie->pcie_data->cfgrd0 : pcie->pcie_data->cfgwr0;
327	u8 cfg1 = read ? pcie->pcie_data->cfgrd1 : pcie->pcie_data->cfgwr1;
328	u8 tag = read ? TLP_READ_TAG : TLP_WRITE_TAG;
329
330	if (pcie->pcie_data->version == ALTERA_PCIE_V1)
331		cfg = (bus == pcie->root_bus_nr) ? cfg0 : cfg1;
332	else
333		cfg = (bus > S10_RP_SECONDARY(pcie)) ? cfg0 : cfg1;
334
335	headers[0] = TLP_CFG_DW0(pcie, cfg);
336	headers[1] = TLP_CFG_DW1(pcie, tag, byte_en);
337	headers[2] = TLP_CFG_DW2(bus, devfn, where);
338}
339
340static int tlp_cfg_dword_read(struct altera_pcie *pcie, u8 bus, u32 devfn,
341			      int where, u8 byte_en, u32 *value)
342{
343	u32 headers[TLP_HDR_SIZE];
344
345	get_tlp_header(pcie, bus, devfn, where, byte_en, true,
346		       headers);
347
348	pcie->pcie_data->ops->tlp_write_pkt(pcie, headers, 0, false);
349
350	return pcie->pcie_data->ops->tlp_read_pkt(pcie, value);
351}
352
353static int tlp_cfg_dword_write(struct altera_pcie *pcie, u8 bus, u32 devfn,
354			       int where, u8 byte_en, u32 value)
355{
356	u32 headers[TLP_HDR_SIZE];
357	int ret;
358
359	get_tlp_header(pcie, bus, devfn, where, byte_en, false,
360		       headers);
361
362	/* check alignment to Qword */
363	if ((where & 0x7) == 0)
364		pcie->pcie_data->ops->tlp_write_pkt(pcie, headers,
365						    value, true);
366	else
367		pcie->pcie_data->ops->tlp_write_pkt(pcie, headers,
368						    value, false);
369
370	ret = pcie->pcie_data->ops->tlp_read_pkt(pcie, NULL);
371	if (ret != PCIBIOS_SUCCESSFUL)
372		return ret;
373
374	/*
375	 * Monitor changes to PCI_PRIMARY_BUS register on root port
376	 * and update local copy of root bus number accordingly.
377	 */
378	if ((bus == pcie->root_bus_nr) && (where == PCI_PRIMARY_BUS))
379		pcie->root_bus_nr = (u8)(value);
380
381	return PCIBIOS_SUCCESSFUL;
382}
383
384static int s10_rp_read_cfg(struct altera_pcie *pcie, int where,
385			   int size, u32 *value)
386{
387	void __iomem *addr = S10_RP_CFG_ADDR(pcie, where);
388
389	switch (size) {
390	case 1:
391		*value = readb(addr);
392		break;
393	case 2:
394		*value = readw(addr);
395		break;
396	default:
397		*value = readl(addr);
398		break;
399	}
400
401	return PCIBIOS_SUCCESSFUL;
402}
403
404static int s10_rp_write_cfg(struct altera_pcie *pcie, u8 busno,
405			    int where, int size, u32 value)
406{
407	void __iomem *addr = S10_RP_CFG_ADDR(pcie, where);
408
409	switch (size) {
410	case 1:
411		writeb(value, addr);
412		break;
413	case 2:
414		writew(value, addr);
415		break;
416	default:
417		writel(value, addr);
418		break;
419	}
420
421	/*
422	 * Monitor changes to PCI_PRIMARY_BUS register on root port
423	 * and update local copy of root bus number accordingly.
424	 */
425	if (busno == pcie->root_bus_nr && where == PCI_PRIMARY_BUS)
426		pcie->root_bus_nr = value & 0xff;
427
428	return PCIBIOS_SUCCESSFUL;
429}
430
431static int _altera_pcie_cfg_read(struct altera_pcie *pcie, u8 busno,
432				 unsigned int devfn, int where, int size,
433				 u32 *value)
434{
435	int ret;
436	u32 data;
437	u8 byte_en;
438
439	if (busno == pcie->root_bus_nr && pcie->pcie_data->ops->rp_read_cfg)
440		return pcie->pcie_data->ops->rp_read_cfg(pcie, where,
441							 size, value);
442
443	switch (size) {
444	case 1:
445		byte_en = 1 << (where & 3);
446		break;
447	case 2:
448		byte_en = 3 << (where & 3);
449		break;
450	default:
451		byte_en = 0xf;
452		break;
453	}
454
455	ret = tlp_cfg_dword_read(pcie, busno, devfn,
456				 (where & ~DWORD_MASK), byte_en, &data);
457	if (ret != PCIBIOS_SUCCESSFUL)
458		return ret;
459
460	switch (size) {
461	case 1:
462		*value = (data >> (8 * (where & 0x3))) & 0xff;
463		break;
464	case 2:
465		*value = (data >> (8 * (where & 0x2))) & 0xffff;
466		break;
467	default:
468		*value = data;
469		break;
470	}
471
472	return PCIBIOS_SUCCESSFUL;
473}
474
475static int _altera_pcie_cfg_write(struct altera_pcie *pcie, u8 busno,
476				  unsigned int devfn, int where, int size,
477				  u32 value)
478{
479	u32 data32;
480	u32 shift = 8 * (where & 3);
481	u8 byte_en;
482
483	if (busno == pcie->root_bus_nr && pcie->pcie_data->ops->rp_write_cfg)
484		return pcie->pcie_data->ops->rp_write_cfg(pcie, busno,
485						     where, size, value);
486
487	switch (size) {
488	case 1:
489		data32 = (value & 0xff) << shift;
490		byte_en = 1 << (where & 3);
491		break;
492	case 2:
493		data32 = (value & 0xffff) << shift;
494		byte_en = 3 << (where & 3);
495		break;
496	default:
497		data32 = value;
498		byte_en = 0xf;
499		break;
500	}
501
502	return tlp_cfg_dword_write(pcie, busno, devfn, (where & ~DWORD_MASK),
503				   byte_en, data32);
504}
505
506static int altera_pcie_cfg_read(struct pci_bus *bus, unsigned int devfn,
507				int where, int size, u32 *value)
508{
509	struct altera_pcie *pcie = bus->sysdata;
510
511	if (altera_pcie_hide_rc_bar(bus, devfn, where))
512		return PCIBIOS_BAD_REGISTER_NUMBER;
513
514	if (!altera_pcie_valid_device(pcie, bus, PCI_SLOT(devfn))) {
515		*value = 0xffffffff;
516		return PCIBIOS_DEVICE_NOT_FOUND;
517	}
518
519	return _altera_pcie_cfg_read(pcie, bus->number, devfn, where, size,
520				     value);
521}
522
523static int altera_pcie_cfg_write(struct pci_bus *bus, unsigned int devfn,
524				 int where, int size, u32 value)
525{
526	struct altera_pcie *pcie = bus->sysdata;
527
528	if (altera_pcie_hide_rc_bar(bus, devfn, where))
529		return PCIBIOS_BAD_REGISTER_NUMBER;
530
531	if (!altera_pcie_valid_device(pcie, bus, PCI_SLOT(devfn)))
532		return PCIBIOS_DEVICE_NOT_FOUND;
533
534	return _altera_pcie_cfg_write(pcie, bus->number, devfn, where, size,
535				     value);
536}
537
538static struct pci_ops altera_pcie_ops = {
539	.read = altera_pcie_cfg_read,
540	.write = altera_pcie_cfg_write,
541};
542
543static int altera_read_cap_word(struct altera_pcie *pcie, u8 busno,
544				unsigned int devfn, int offset, u16 *value)
545{
546	u32 data;
547	int ret;
548
549	ret = _altera_pcie_cfg_read(pcie, busno, devfn,
550				    pcie->pcie_data->cap_offset + offset,
551				    sizeof(*value),
552				    &data);
553	*value = data;
554	return ret;
555}
556
557static int altera_write_cap_word(struct altera_pcie *pcie, u8 busno,
558				 unsigned int devfn, int offset, u16 value)
559{
560	return _altera_pcie_cfg_write(pcie, busno, devfn,
561				      pcie->pcie_data->cap_offset + offset,
562				      sizeof(value),
563				      value);
564}
565
566static void altera_wait_link_retrain(struct altera_pcie *pcie)
567{
568	struct device *dev = &pcie->pdev->dev;
569	u16 reg16;
570	unsigned long start_jiffies;
571
572	/* Wait for link training end. */
573	start_jiffies = jiffies;
574	for (;;) {
575		altera_read_cap_word(pcie, pcie->root_bus_nr, RP_DEVFN,
576				     PCI_EXP_LNKSTA, &reg16);
577		if (!(reg16 & PCI_EXP_LNKSTA_LT))
578			break;
579
580		if (time_after(jiffies, start_jiffies + LINK_RETRAIN_TIMEOUT)) {
581			dev_err(dev, "link retrain timeout\n");
582			break;
583		}
584		udelay(100);
585	}
586
587	/* Wait for link is up */
588	start_jiffies = jiffies;
589	for (;;) {
590		if (pcie->pcie_data->ops->get_link_status(pcie))
591			break;
592
593		if (time_after(jiffies, start_jiffies + LINK_UP_TIMEOUT)) {
594			dev_err(dev, "link up timeout\n");
595			break;
596		}
597		udelay(100);
598	}
599}
600
601static void altera_pcie_retrain(struct altera_pcie *pcie)
602{
603	u16 linkcap, linkstat, linkctl;
604
605	if (!pcie->pcie_data->ops->get_link_status(pcie))
606		return;
607
608	/*
609	 * Set the retrain bit if the PCIe rootport support > 2.5GB/s, but
610	 * current speed is 2.5 GB/s.
611	 */
612	altera_read_cap_word(pcie, pcie->root_bus_nr, RP_DEVFN, PCI_EXP_LNKCAP,
613			     &linkcap);
614	if ((linkcap & PCI_EXP_LNKCAP_SLS) <= PCI_EXP_LNKCAP_SLS_2_5GB)
615		return;
616
617	altera_read_cap_word(pcie, pcie->root_bus_nr, RP_DEVFN, PCI_EXP_LNKSTA,
618			     &linkstat);
619	if ((linkstat & PCI_EXP_LNKSTA_CLS) == PCI_EXP_LNKSTA_CLS_2_5GB) {
620		altera_read_cap_word(pcie, pcie->root_bus_nr, RP_DEVFN,
621				     PCI_EXP_LNKCTL, &linkctl);
622		linkctl |= PCI_EXP_LNKCTL_RL;
623		altera_write_cap_word(pcie, pcie->root_bus_nr, RP_DEVFN,
624				      PCI_EXP_LNKCTL, linkctl);
625
626		altera_wait_link_retrain(pcie);
627	}
628}
629
630static int altera_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
631				irq_hw_number_t hwirq)
632{
633	irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_simple_irq);
634	irq_set_chip_data(irq, domain->host_data);
635	return 0;
636}
637
638static const struct irq_domain_ops intx_domain_ops = {
639	.map = altera_pcie_intx_map,
640	.xlate = pci_irqd_intx_xlate,
641};
642
643static void altera_pcie_isr(struct irq_desc *desc)
644{
645	struct irq_chip *chip = irq_desc_get_chip(desc);
646	struct altera_pcie *pcie;
647	struct device *dev;
648	unsigned long status;
649	u32 bit;
650	u32 virq;
651
652	chained_irq_enter(chip, desc);
653	pcie = irq_desc_get_handler_data(desc);
654	dev = &pcie->pdev->dev;
655
656	while ((status = cra_readl(pcie, P2A_INT_STATUS)
657		& P2A_INT_STS_ALL) != 0) {
658		for_each_set_bit(bit, &status, PCI_NUM_INTX) {
659			/* clear interrupts */
660			cra_writel(pcie, 1 << bit, P2A_INT_STATUS);
661
662			virq = irq_find_mapping(pcie->irq_domain, bit);
663			if (virq)
664				generic_handle_irq(virq);
665			else
666				dev_err(dev, "unexpected IRQ, INT%d\n", bit);
667		}
668	}
669
670	chained_irq_exit(chip, desc);
671}
672
673static int altera_pcie_parse_request_of_pci_ranges(struct altera_pcie *pcie)
674{
675	int err, res_valid = 0;
676	struct device *dev = &pcie->pdev->dev;
677	struct resource_entry *win;
678
679	err = devm_of_pci_get_host_bridge_resources(dev, 0, 0xff,
680						    &pcie->resources, NULL);
681	if (err)
682		return err;
683
684	err = devm_request_pci_bus_resources(dev, &pcie->resources);
685	if (err)
686		goto out_release_res;
687
688	resource_list_for_each_entry(win, &pcie->resources) {
689		struct resource *res = win->res;
690
691		if (resource_type(res) == IORESOURCE_MEM)
692			res_valid |= !(res->flags & IORESOURCE_PREFETCH);
693	}
694
695	if (res_valid)
696		return 0;
697
698	dev_err(dev, "non-prefetchable memory resource required\n");
699	err = -EINVAL;
700
701out_release_res:
702	pci_free_resource_list(&pcie->resources);
703	return err;
704}
705
706static int altera_pcie_init_irq_domain(struct altera_pcie *pcie)
707{
708	struct device *dev = &pcie->pdev->dev;
709	struct device_node *node = dev->of_node;
710
711	/* Setup INTx */
712	pcie->irq_domain = irq_domain_add_linear(node, PCI_NUM_INTX,
713					&intx_domain_ops, pcie);
714	if (!pcie->irq_domain) {
715		dev_err(dev, "Failed to get a INTx IRQ domain\n");
716		return -ENOMEM;
717	}
718
719	return 0;
720}
721
722static void altera_pcie_irq_teardown(struct altera_pcie *pcie)
723{
724	irq_set_chained_handler_and_data(pcie->irq, NULL, NULL);
725	irq_domain_remove(pcie->irq_domain);
726	irq_dispose_mapping(pcie->irq);
727}
728
729static int altera_pcie_parse_dt(struct altera_pcie *pcie)
730{
731	struct device *dev = &pcie->pdev->dev;
732	struct platform_device *pdev = pcie->pdev;
733	struct resource *cra;
734	struct resource *hip;
735
736	cra = platform_get_resource_byname(pdev, IORESOURCE_MEM, "Cra");
737	pcie->cra_base = devm_ioremap_resource(dev, cra);
738	if (IS_ERR(pcie->cra_base))
739		return PTR_ERR(pcie->cra_base);
740
741	if (pcie->pcie_data->version == ALTERA_PCIE_V2) {
742		hip = platform_get_resource_byname(pdev, IORESOURCE_MEM, "Hip");
743		pcie->hip_base = devm_ioremap_resource(&pdev->dev, hip);
744		if (IS_ERR(pcie->hip_base))
745			return PTR_ERR(pcie->hip_base);
746	}
747
748	/* setup IRQ */
749	pcie->irq = platform_get_irq(pdev, 0);
750	if (pcie->irq < 0) {
751		dev_err(dev, "failed to get IRQ: %d\n", pcie->irq);
752		return pcie->irq;
753	}
754
755	irq_set_chained_handler_and_data(pcie->irq, altera_pcie_isr, pcie);
756	return 0;
757}
758
759static void altera_pcie_host_init(struct altera_pcie *pcie)
760{
761	altera_pcie_retrain(pcie);
762}
763
764static const struct altera_pcie_ops altera_pcie_ops_1_0 = {
765	.tlp_read_pkt = tlp_read_packet,
766	.tlp_write_pkt = tlp_write_packet,
767	.get_link_status = altera_pcie_link_up,
768};
769
770static const struct altera_pcie_ops altera_pcie_ops_2_0 = {
771	.tlp_read_pkt = s10_tlp_read_packet,
772	.tlp_write_pkt = s10_tlp_write_packet,
773	.get_link_status = s10_altera_pcie_link_up,
774	.rp_read_cfg = s10_rp_read_cfg,
775	.rp_write_cfg = s10_rp_write_cfg,
776};
777
778static const struct altera_pcie_data altera_pcie_1_0_data = {
779	.ops = &altera_pcie_ops_1_0,
780	.cap_offset = 0x80,
781	.version = ALTERA_PCIE_V1,
782	.cfgrd0 = TLP_FMTTYPE_CFGRD0,
783	.cfgrd1 = TLP_FMTTYPE_CFGRD1,
784	.cfgwr0 = TLP_FMTTYPE_CFGWR0,
785	.cfgwr1 = TLP_FMTTYPE_CFGWR1,
786};
787
788static const struct altera_pcie_data altera_pcie_2_0_data = {
789	.ops = &altera_pcie_ops_2_0,
790	.version = ALTERA_PCIE_V2,
791	.cap_offset = 0x70,
792	.cfgrd0 = S10_TLP_FMTTYPE_CFGRD0,
793	.cfgrd1 = S10_TLP_FMTTYPE_CFGRD1,
794	.cfgwr0 = S10_TLP_FMTTYPE_CFGWR0,
795	.cfgwr1 = S10_TLP_FMTTYPE_CFGWR1,
796};
797
798static const struct of_device_id altera_pcie_of_match[] = {
799	{.compatible = "altr,pcie-root-port-1.0",
800	 .data = &altera_pcie_1_0_data },
801	{.compatible = "altr,pcie-root-port-2.0",
802	 .data = &altera_pcie_2_0_data },
803	{},
804};
805
806static int altera_pcie_probe(struct platform_device *pdev)
807{
808	struct device *dev = &pdev->dev;
809	struct altera_pcie *pcie;
810	struct pci_bus *bus;
811	struct pci_bus *child;
812	struct pci_host_bridge *bridge;
813	int ret;
814	const struct of_device_id *match;
815
816	bridge = devm_pci_alloc_host_bridge(dev, sizeof(*pcie));
817	if (!bridge)
818		return -ENOMEM;
819
820	pcie = pci_host_bridge_priv(bridge);
821	pcie->pdev = pdev;
822	platform_set_drvdata(pdev, pcie);
823
824	match = of_match_device(altera_pcie_of_match, &pdev->dev);
825	if (!match)
826		return -ENODEV;
827
828	pcie->pcie_data = match->data;
829
830	ret = altera_pcie_parse_dt(pcie);
831	if (ret) {
832		dev_err(dev, "Parsing DT failed\n");
833		return ret;
834	}
835
836	INIT_LIST_HEAD(&pcie->resources);
837
838	ret = altera_pcie_parse_request_of_pci_ranges(pcie);
839	if (ret) {
840		dev_err(dev, "Failed add resources\n");
841		return ret;
842	}
843
844	ret = altera_pcie_init_irq_domain(pcie);
845	if (ret) {
846		dev_err(dev, "Failed creating IRQ Domain\n");
847		return ret;
848	}
849
850	/* clear all interrupts */
851	cra_writel(pcie, P2A_INT_STS_ALL, P2A_INT_STATUS);
852	/* enable all interrupts */
853	cra_writel(pcie, P2A_INT_ENA_ALL, P2A_INT_ENABLE);
854	altera_pcie_host_init(pcie);
855
856	list_splice_init(&pcie->resources, &bridge->windows);
857	bridge->dev.parent = dev;
858	bridge->sysdata = pcie;
859	bridge->busnr = pcie->root_bus_nr;
860	bridge->ops = &altera_pcie_ops;
861	bridge->map_irq = of_irq_parse_and_map_pci;
862	bridge->swizzle_irq = pci_common_swizzle;
863
864	ret = pci_scan_root_bus_bridge(bridge);
865	if (ret < 0)
866		return ret;
867
868	bus = bridge->bus;
869
870	pci_assign_unassigned_bus_resources(bus);
871
872	/* Configure PCI Express setting. */
873	list_for_each_entry(child, &bus->children, node)
874		pcie_bus_configure_settings(child);
875
876	pci_bus_add_devices(bus);
877	return ret;
878}
879
880static int altera_pcie_remove(struct platform_device *pdev)
881{
882	struct altera_pcie *pcie = platform_get_drvdata(pdev);
883	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
884
885	pci_stop_root_bus(bridge->bus);
886	pci_remove_root_bus(bridge->bus);
887	pci_free_resource_list(&pcie->resources);
888	altera_pcie_irq_teardown(pcie);
889
890	return 0;
891}
892
893static struct platform_driver altera_pcie_driver = {
894	.probe		= altera_pcie_probe,
895	.remove		= altera_pcie_remove,
896	.driver = {
897		.name	= "altera-pcie",
898		.of_match_table = altera_pcie_of_match,
899	},
900};
901
902MODULE_DEVICE_TABLE(of, altera_pcie_of_match);
903module_platform_driver(altera_pcie_driver);
904MODULE_LICENSE("GPL v2");