1/*
2 * Copyright (c) 2003-2012 Broadcom Corporation
3 * All Rights Reserved
4 *
5 * This software is available to you under a choice of one of two
6 * licenses.  You may choose to be licensed under the terms of the GNU
7 * General Public License (GPL) Version 2, available from the file
8 * COPYING in the main directory of this source tree, or the Broadcom
9 * license below:
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 *
15 * 1. Redistributions of source code must retain the above copyright
16 *    notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 *    notice, this list of conditions and the following disclaimer in
19 *    the documentation and/or other materials provided with the
20 *    distribution.
21 *
22 * THIS SOFTWARE IS PROVIDED BY BROADCOM ``AS IS'' AND ANY EXPRESS OR
23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
24 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL BROADCOM OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
29 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
30 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
31 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
32 * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33 */
34
35#include <linux/types.h>
36#include <linux/pci.h>
37#include <linux/kernel.h>
38#include <linux/init.h>
39#include <linux/msi.h>
40#include <linux/mm.h>
41#include <linux/irq.h>
42#include <linux/irqdesc.h>
43#include <linux/console.h>
44
45#include <asm/io.h>
46
47#include <asm/netlogic/interrupt.h>
48#include <asm/netlogic/haldefs.h>
49#include <asm/netlogic/common.h>
50#include <asm/netlogic/mips-extns.h>
51
52#include <asm/netlogic/xlp-hal/iomap.h>
53#include <asm/netlogic/xlp-hal/xlp.h>
54#include <asm/netlogic/xlp-hal/pic.h>
55#include <asm/netlogic/xlp-hal/pcibus.h>
56#include <asm/netlogic/xlp-hal/bridge.h>
57
58#define XLP_MSIVEC_PER_LINK	32
59#define XLP_MSIXVEC_TOTAL	(cpu_is_xlp9xx() ? 128 : 32)
60#define XLP_MSIXVEC_PER_LINK	(cpu_is_xlp9xx() ? 32 : 8)
61
62/* 128 MSI irqs per node, mapped starting at NLM_MSI_VEC_BASE */
63static inline int nlm_link_msiirq(int link, int msivec)
64{
65	return NLM_MSI_VEC_BASE + link * XLP_MSIVEC_PER_LINK + msivec;
66}
67
68/* get the link MSI vector from irq number */
69static inline int nlm_irq_msivec(int irq)
70{
71	return (irq - NLM_MSI_VEC_BASE) % XLP_MSIVEC_PER_LINK;
72}
73
74/* get the link from the irq number */
75static inline int nlm_irq_msilink(int irq)
76{
77	int total_msivec = XLP_MSIVEC_PER_LINK * PCIE_NLINKS;
78
79	return ((irq - NLM_MSI_VEC_BASE) % total_msivec) /
80		XLP_MSIVEC_PER_LINK;
81}
82
83/*
84 * For XLP 8xx/4xx/3xx/2xx, only 32 MSI-X vectors are possible because
85 * there are only 32 PIC interrupts for MSI. We split them statically
86 * and use 8 MSI-X vectors per link - this keeps the allocation and
87 * lookup simple.
88 * On XLP 9xx, there are 32 vectors per link, and the interrupts are
89 * not routed thru PIC, so we can use all 128 MSI-X vectors.
90 */
91static inline int nlm_link_msixirq(int link, int bit)
92{
93	return NLM_MSIX_VEC_BASE + link * XLP_MSIXVEC_PER_LINK + bit;
94}
95
96/* get the link MSI vector from irq number */
97static inline int nlm_irq_msixvec(int irq)
98{
99	return (irq - NLM_MSIX_VEC_BASE) % XLP_MSIXVEC_TOTAL;
100}
101
102/* get the link from MSIX vec */
103static inline int nlm_irq_msixlink(int msixvec)
104{
105	return msixvec / XLP_MSIXVEC_PER_LINK;
106}
107
108/*
109 * Per link MSI and MSI-X information, set as IRQ handler data for
110 * MSI and MSI-X interrupts.
111 */
112struct xlp_msi_data {
113	struct nlm_soc_info *node;
114	uint64_t	lnkbase;
115	uint32_t	msi_enabled_mask;
116	uint32_t	msi_alloc_mask;
117	uint32_t	msix_alloc_mask;
118	spinlock_t	msi_lock;
119};
120
121/*
122 * MSI Chip definitions
123 *
124 * On XLP, there is a PIC interrupt associated with each PCIe link on the
125 * chip (which appears as a PCI bridge to us). This gives us 32 MSI irqa
126 * per link and 128 overall.
127 *
128 * When a device connected to the link raises a MSI interrupt, we get a
129 * link interrupt and we then have to look at PCIE_MSI_STATUS register at
130 * the bridge to map it to the IRQ
131 */
132static void xlp_msi_enable(struct irq_data *d)
133{
134	struct xlp_msi_data *md = irq_data_get_irq_handler_data(d);
135	unsigned long flags;
136	int vec;
137
138	vec = nlm_irq_msivec(d->irq);
139	spin_lock_irqsave(&md->msi_lock, flags);
140	md->msi_enabled_mask |= 1u << vec;
141	if (cpu_is_xlp9xx())
142		nlm_write_reg(md->lnkbase, PCIE_9XX_MSI_EN,
143				md->msi_enabled_mask);
144	else
145		nlm_write_reg(md->lnkbase, PCIE_MSI_EN, md->msi_enabled_mask);
146	spin_unlock_irqrestore(&md->msi_lock, flags);
147}
148
149static void xlp_msi_disable(struct irq_data *d)
150{
151	struct xlp_msi_data *md = irq_data_get_irq_handler_data(d);
152	unsigned long flags;
153	int vec;
154
155	vec = nlm_irq_msivec(d->irq);
156	spin_lock_irqsave(&md->msi_lock, flags);
157	md->msi_enabled_mask &= ~(1u << vec);
158	if (cpu_is_xlp9xx())
159		nlm_write_reg(md->lnkbase, PCIE_9XX_MSI_EN,
160				md->msi_enabled_mask);
161	else
162		nlm_write_reg(md->lnkbase, PCIE_MSI_EN, md->msi_enabled_mask);
163	spin_unlock_irqrestore(&md->msi_lock, flags);
164}
165
166static void xlp_msi_mask_ack(struct irq_data *d)
167{
168	struct xlp_msi_data *md = irq_data_get_irq_handler_data(d);
169	int link, vec;
170
171	link = nlm_irq_msilink(d->irq);
172	vec = nlm_irq_msivec(d->irq);
173	xlp_msi_disable(d);
174
175	/* Ack MSI on bridge */
176	if (cpu_is_xlp9xx())
177		nlm_write_reg(md->lnkbase, PCIE_9XX_MSI_STATUS, 1u << vec);
178	else
179		nlm_write_reg(md->lnkbase, PCIE_MSI_STATUS, 1u << vec);
180
181}
182
183static struct irq_chip xlp_msi_chip = {
184	.name		= "XLP-MSI",
185	.irq_enable	= xlp_msi_enable,
186	.irq_disable	= xlp_msi_disable,
187	.irq_mask_ack	= xlp_msi_mask_ack,
188	.irq_unmask	= xlp_msi_enable,
189};
190
191/*
192 * XLP8XX/4XX/3XX/2XX:
193 * The MSI-X interrupt handling is different from MSI, there are 32 MSI-X
194 * interrupts generated by the PIC and each of these correspond to a MSI-X
195 * vector (0-31) that can be assigned.
196 *
197 * We divide the MSI-X vectors to 8 per link and do a per-link allocation
198 *
199 * XLP9XX:
200 * 32 MSI-X vectors are available per link, and the interrupts are not routed
201 * thru the PIC. PIC ack not needed.
202 *
203 * Enable and disable done using standard MSI functions.
204 */
205static void xlp_msix_mask_ack(struct irq_data *d)
206{
207	struct xlp_msi_data *md;
208	int link, msixvec;
209	uint32_t status_reg, bit;
210
211	msixvec = nlm_irq_msixvec(d->irq);
212	link = nlm_irq_msixlink(msixvec);
213	pci_msi_mask_irq(d);
214	md = irq_data_get_irq_handler_data(d);
215
216	/* Ack MSI on bridge */
217	if (cpu_is_xlp9xx()) {
218		status_reg = PCIE_9XX_MSIX_STATUSX(link);
219		bit = msixvec % XLP_MSIXVEC_PER_LINK;
220	} else {
221		status_reg = PCIE_MSIX_STATUS;
222		bit = msixvec;
223	}
224	nlm_write_reg(md->lnkbase, status_reg, 1u << bit);
225
226	if (!cpu_is_xlp9xx())
227		nlm_pic_ack(md->node->picbase,
228				PIC_IRT_PCIE_MSIX_INDEX(msixvec));
229}
230
231static struct irq_chip xlp_msix_chip = {
232	.name		= "XLP-MSIX",
233	.irq_enable	= pci_msi_unmask_irq,
234	.irq_disable	= pci_msi_mask_irq,
235	.irq_mask_ack	= xlp_msix_mask_ack,
236	.irq_unmask	= pci_msi_unmask_irq,
237};
238
239void arch_teardown_msi_irq(unsigned int irq)
240{
241}
242
243/*
244 * Setup a PCIe link for MSI.  By default, the links are in
245 * legacy interrupt mode.  We will switch them to MSI mode
246 * at the first MSI request.
247 */
248static void xlp_config_link_msi(uint64_t lnkbase, int lirq, uint64_t msiaddr)
249{
250	u32 val;
251
252	if (cpu_is_xlp9xx()) {
253		val = nlm_read_reg(lnkbase, PCIE_9XX_INT_EN0);
254		if ((val & 0x200) == 0) {
255			val |= 0x200;		/* MSI Interrupt enable */
256			nlm_write_reg(lnkbase, PCIE_9XX_INT_EN0, val);
257		}
258	} else {
259		val = nlm_read_reg(lnkbase, PCIE_INT_EN0);
260		if ((val & 0x200) == 0) {
261			val |= 0x200;
262			nlm_write_reg(lnkbase, PCIE_INT_EN0, val);
263		}
264	}
265
266	val = nlm_read_reg(lnkbase, 0x1);	/* CMD */
267	if ((val & 0x0400) == 0) {
268		val |= 0x0400;
269		nlm_write_reg(lnkbase, 0x1, val);
270	}
271
272	/* Update IRQ in the PCI irq reg */
273	val = nlm_read_pci_reg(lnkbase, 0xf);
274	val &= ~0x1fu;
275	val |= (1 << 8) | lirq;
276	nlm_write_pci_reg(lnkbase, 0xf, val);
277
278	/* MSI addr */
279	nlm_write_reg(lnkbase, PCIE_BRIDGE_MSI_ADDRH, msiaddr >> 32);
280	nlm_write_reg(lnkbase, PCIE_BRIDGE_MSI_ADDRL, msiaddr & 0xffffffff);
281
282	/* MSI cap for bridge */
283	val = nlm_read_reg(lnkbase, PCIE_BRIDGE_MSI_CAP);
284	if ((val & (1 << 16)) == 0) {
285		val |= 0xb << 16;		/* mmc32, msi enable */
286		nlm_write_reg(lnkbase, PCIE_BRIDGE_MSI_CAP, val);
287	}
288}
289
290/*
291 * Allocate a MSI vector on a link
292 */
293static int xlp_setup_msi(uint64_t lnkbase, int node, int link,
294	struct msi_desc *desc)
295{
296	struct xlp_msi_data *md;
297	struct msi_msg msg;
298	unsigned long flags;
299	int msivec, irt, lirq, xirq, ret;
300	uint64_t msiaddr;
301
302	/* Get MSI data for the link */
303	lirq = PIC_PCIE_LINK_MSI_IRQ(link);
304	xirq = nlm_irq_to_xirq(node, nlm_link_msiirq(link, 0));
305	md = irq_get_handler_data(xirq);
306	msiaddr = MSI_LINK_ADDR(node, link);
307
308	spin_lock_irqsave(&md->msi_lock, flags);
309	if (md->msi_alloc_mask == 0) {
310		xlp_config_link_msi(lnkbase, lirq, msiaddr);
311		/* switch the link IRQ to MSI range */
312		if (cpu_is_xlp9xx())
313			irt = PIC_9XX_IRT_PCIE_LINK_INDEX(link);
314		else
315			irt = PIC_IRT_PCIE_LINK_INDEX(link);
316		nlm_setup_pic_irq(node, lirq, lirq, irt);
317		nlm_pic_init_irt(nlm_get_node(node)->picbase, irt, lirq,
318				 node * nlm_threads_per_node(), 1 /*en */);
319	}
320
321	/* allocate a MSI vec, and tell the bridge about it */
322	msivec = fls(md->msi_alloc_mask);
323	if (msivec == XLP_MSIVEC_PER_LINK) {
324		spin_unlock_irqrestore(&md->msi_lock, flags);
325		return -ENOMEM;
326	}
327	md->msi_alloc_mask |= (1u << msivec);
328	spin_unlock_irqrestore(&md->msi_lock, flags);
329
330	msg.address_hi = msiaddr >> 32;
331	msg.address_lo = msiaddr & 0xffffffff;
332	msg.data = 0xc00 | msivec;
333
334	xirq = xirq + msivec;		/* msi mapped to global irq space */
335	ret = irq_set_msi_desc(xirq, desc);
336	if (ret < 0)
337		return ret;
338
339	pci_write_msi_msg(xirq, &msg);
340	return 0;
341}
342
343/*
344 * Switch a link to MSI-X mode
345 */
346static void xlp_config_link_msix(uint64_t lnkbase, int lirq, uint64_t msixaddr)
347{
348	u32 val;
349
350	val = nlm_read_reg(lnkbase, 0x2C);
351	if ((val & 0x80000000U) == 0) {
352		val |= 0x80000000U;
353		nlm_write_reg(lnkbase, 0x2C, val);
354	}
355
356	if (cpu_is_xlp9xx()) {
357		val = nlm_read_reg(lnkbase, PCIE_9XX_INT_EN0);
358		if ((val & 0x200) == 0) {
359			val |= 0x200;		/* MSI Interrupt enable */
360			nlm_write_reg(lnkbase, PCIE_9XX_INT_EN0, val);
361		}
362	} else {
363		val = nlm_read_reg(lnkbase, PCIE_INT_EN0);
364		if ((val & 0x200) == 0) {
365			val |= 0x200;		/* MSI Interrupt enable */
366			nlm_write_reg(lnkbase, PCIE_INT_EN0, val);
367		}
368	}
369
370	val = nlm_read_reg(lnkbase, 0x1);	/* CMD */
371	if ((val & 0x0400) == 0) {
372		val |= 0x0400;
373		nlm_write_reg(lnkbase, 0x1, val);
374	}
375
376	/* Update IRQ in the PCI irq reg */
377	val = nlm_read_pci_reg(lnkbase, 0xf);
378	val &= ~0x1fu;
379	val |= (1 << 8) | lirq;
380	nlm_write_pci_reg(lnkbase, 0xf, val);
381
382	if (cpu_is_xlp9xx()) {
383		/* MSI-X addresses */
384		nlm_write_reg(lnkbase, PCIE_9XX_BRIDGE_MSIX_ADDR_BASE,
385				msixaddr >> 8);
386		nlm_write_reg(lnkbase, PCIE_9XX_BRIDGE_MSIX_ADDR_LIMIT,
387				(msixaddr + MSI_ADDR_SZ) >> 8);
388	} else {
389		/* MSI-X addresses */
390		nlm_write_reg(lnkbase, PCIE_BRIDGE_MSIX_ADDR_BASE,
391				msixaddr >> 8);
392		nlm_write_reg(lnkbase, PCIE_BRIDGE_MSIX_ADDR_LIMIT,
393				(msixaddr + MSI_ADDR_SZ) >> 8);
394	}
395}
396
397/*
398 *  Allocate a MSI-X vector
399 */
400static int xlp_setup_msix(uint64_t lnkbase, int node, int link,
401	struct msi_desc *desc)
402{
403	struct xlp_msi_data *md;
404	struct msi_msg msg;
405	unsigned long flags;
406	int t, msixvec, lirq, xirq, ret;
407	uint64_t msixaddr;
408
409	/* Get MSI data for the link */
410	lirq = PIC_PCIE_MSIX_IRQ(link);
411	xirq = nlm_irq_to_xirq(node, nlm_link_msixirq(link, 0));
412	md = irq_get_handler_data(xirq);
413	msixaddr = MSIX_LINK_ADDR(node, link);
414
415	spin_lock_irqsave(&md->msi_lock, flags);
416	/* switch the PCIe link to MSI-X mode at the first alloc */
417	if (md->msix_alloc_mask == 0)
418		xlp_config_link_msix(lnkbase, lirq, msixaddr);
419
420	/* allocate a MSI-X vec, and tell the bridge about it */
421	t = fls(md->msix_alloc_mask);
422	if (t == XLP_MSIXVEC_PER_LINK) {
423		spin_unlock_irqrestore(&md->msi_lock, flags);
424		return -ENOMEM;
425	}
426	md->msix_alloc_mask |= (1u << t);
427	spin_unlock_irqrestore(&md->msi_lock, flags);
428
429	xirq += t;
430	msixvec = nlm_irq_msixvec(xirq);
431
432	msg.address_hi = msixaddr >> 32;
433	msg.address_lo = msixaddr & 0xffffffff;
434	msg.data = 0xc00 | msixvec;
435
436	ret = irq_set_msi_desc(xirq, desc);
437	if (ret < 0)
438		return ret;
439
440	pci_write_msi_msg(xirq, &msg);
441	return 0;
442}
443
444int arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc)
445{
446	struct pci_dev *lnkdev;
447	uint64_t lnkbase;
448	int node, link, slot;
449
450	lnkdev = xlp_get_pcie_link(dev);
451	if (lnkdev == NULL) {
452		dev_err(&dev->dev, "Could not find bridge\n");
453		return 1;
454	}
455	slot = PCI_SLOT(lnkdev->devfn);
456	link = PCI_FUNC(lnkdev->devfn);
457	node = slot / 8;
458	lnkbase = nlm_get_pcie_base(node, link);
459
460	if (desc->msi_attrib.is_msix)
461		return xlp_setup_msix(lnkbase, node, link, desc);
462	else
463		return xlp_setup_msi(lnkbase, node, link, desc);
464}
465
466void __init xlp_init_node_msi_irqs(int node, int link)
467{
468	struct nlm_soc_info *nodep;
469	struct xlp_msi_data *md;
470	int irq, i, irt, msixvec, val;
471
472	pr_info("[%d %d] Init node PCI IRT\n", node, link);
473	nodep = nlm_get_node(node);
474
475	/* Alloc an MSI block for the link */
476	md = kzalloc(sizeof(*md), GFP_KERNEL);
477	spin_lock_init(&md->msi_lock);
478	md->msi_enabled_mask = 0;
479	md->msi_alloc_mask = 0;
480	md->msix_alloc_mask = 0;
481	md->node = nodep;
482	md->lnkbase = nlm_get_pcie_base(node, link);
483
484	/* extended space for MSI interrupts */
485	irq = nlm_irq_to_xirq(node, nlm_link_msiirq(link, 0));
486	for (i = irq; i < irq + XLP_MSIVEC_PER_LINK; i++) {
487		irq_set_chip_and_handler(i, &xlp_msi_chip, handle_level_irq);
488		irq_set_handler_data(i, md);
489	}
490
491	for (i = 0; i < XLP_MSIXVEC_PER_LINK ; i++) {
492		if (cpu_is_xlp9xx()) {
493			val = ((node * nlm_threads_per_node()) << 7 |
494				PIC_PCIE_MSIX_IRQ(link) << 1 | 0 << 0);
495			nlm_write_pcie_reg(md->lnkbase, PCIE_9XX_MSIX_VECX(i +
496					(link * XLP_MSIXVEC_PER_LINK)), val);
497		} else {
498			/* Initialize MSI-X irts to generate one interrupt
499			 * per link
500			 */
501			msixvec = link * XLP_MSIXVEC_PER_LINK + i;
502			irt = PIC_IRT_PCIE_MSIX_INDEX(msixvec);
503			nlm_pic_init_irt(nodep->picbase, irt,
504					PIC_PCIE_MSIX_IRQ(link),
505					node * nlm_threads_per_node(), 1);
506		}
507
508		/* Initialize MSI-X extended irq space for the link  */
509		irq = nlm_irq_to_xirq(node, nlm_link_msixirq(link, i));
510		irq_set_chip_and_handler(irq, &xlp_msix_chip, handle_level_irq);
511		irq_set_handler_data(irq, md);
512	}
513}
514
515void nlm_dispatch_msi(int node, int lirq)
516{
517	struct xlp_msi_data *md;
518	int link, i, irqbase;
519	u32 status;
520
521	link = lirq - PIC_PCIE_LINK_MSI_IRQ_BASE;
522	irqbase = nlm_irq_to_xirq(node, nlm_link_msiirq(link, 0));
523	md = irq_get_handler_data(irqbase);
524	if (cpu_is_xlp9xx())
525		status = nlm_read_reg(md->lnkbase, PCIE_9XX_MSI_STATUS) &
526						md->msi_enabled_mask;
527	else
528		status = nlm_read_reg(md->lnkbase, PCIE_MSI_STATUS) &
529						md->msi_enabled_mask;
530	while (status) {
531		i = __ffs(status);
532		do_IRQ(irqbase + i);
533		status &= status - 1;
534	}
535
536	/* Ack at eirr and PIC */
537	ack_c0_eirr(PIC_PCIE_LINK_MSI_IRQ(link));
538	if (cpu_is_xlp9xx())
539		nlm_pic_ack(md->node->picbase,
540				PIC_9XX_IRT_PCIE_LINK_INDEX(link));
541	else
542		nlm_pic_ack(md->node->picbase, PIC_IRT_PCIE_LINK_INDEX(link));
543}
544
545void nlm_dispatch_msix(int node, int lirq)
546{
547	struct xlp_msi_data *md;
548	int link, i, irqbase;
549	u32 status;
550
551	link = lirq - PIC_PCIE_MSIX_IRQ_BASE;
552	irqbase = nlm_irq_to_xirq(node, nlm_link_msixirq(link, 0));
553	md = irq_get_handler_data(irqbase);
554	if (cpu_is_xlp9xx())
555		status = nlm_read_reg(md->lnkbase, PCIE_9XX_MSIX_STATUSX(link));
556	else
557		status = nlm_read_reg(md->lnkbase, PCIE_MSIX_STATUS);
558
559	/* narrow it down to the MSI-x vectors for our link */
560	if (!cpu_is_xlp9xx())
561		status = (status >> (link * XLP_MSIXVEC_PER_LINK)) &
562			((1 << XLP_MSIXVEC_PER_LINK) - 1);
563
564	while (status) {
565		i = __ffs(status);
566		do_IRQ(irqbase + i);
567		status &= status - 1;
568	}
569	/* Ack at eirr and PIC */
570	ack_c0_eirr(PIC_PCIE_MSIX_IRQ(link));
571}
572