1// SPDX-License-Identifier: GPL-2.0+
2// Copyright 2017 IBM Corp.
3#include <asm/pnv-ocxl.h>
4#include <asm/opal.h>
5#include <misc/ocxl-config.h>
6#include "pci.h"
7
8#define PNV_OCXL_TL_P9_RECV_CAP		0x000000000000000Full
9#define PNV_OCXL_ACTAG_MAX		64
10/* PASIDs are 20-bit, but on P9, NPU can only handle 15 bits */
11#define PNV_OCXL_PASID_BITS		15
12#define PNV_OCXL_PASID_MAX		((1 << PNV_OCXL_PASID_BITS) - 1)
13
14#define AFU_PRESENT (1 << 31)
15#define AFU_INDEX_MASK 0x3F000000
16#define AFU_INDEX_SHIFT 24
17#define ACTAG_MASK 0xFFF
18
19
20struct actag_range {
21	u16 start;
22	u16 count;
23};
24
25struct npu_link {
26	struct list_head list;
27	int domain;
28	int bus;
29	int dev;
30	u16 fn_desired_actags[8];
31	struct actag_range fn_actags[8];
32	bool assignment_done;
33};
34static struct list_head links_list = LIST_HEAD_INIT(links_list);
35static DEFINE_MUTEX(links_list_lock);
36
37
38/*
39 * opencapi actags handling:
40 *
41 * When sending commands, the opencapi device references the memory
42 * context it's targeting with an 'actag', which is really an alias
43 * for a (BDF, pasid) combination. When it receives a command, the NPU
44 * must do a lookup of the actag to identify the memory context. The
45 * hardware supports a finite number of actags per link (64 for
46 * POWER9).
47 *
48 * The device can carry multiple functions, and each function can have
49 * multiple AFUs. Each AFU advertises in its config space the number
50 * of desired actags. The host must configure in the config space of
51 * the AFU how many actags the AFU is really allowed to use (which can
52 * be less than what the AFU desires).
53 *
54 * When a PCI function is probed by the driver, it has no visibility
55 * about the other PCI functions and how many actags they'd like,
56 * which makes it impossible to distribute actags fairly among AFUs.
57 *
58 * Unfortunately, the only way to know how many actags a function
59 * desires is by looking at the data for each AFU in the config space
60 * and add them up. Similarly, the only way to know how many actags
61 * all the functions of the physical device desire is by adding the
62 * previously computed function counts. Then we can match that against
63 * what the hardware supports.
64 *
65 * To get a comprehensive view, we use a 'pci fixup': at the end of
66 * PCI enumeration, each function counts how many actags its AFUs
67 * desire and we save it in a 'npu_link' structure, shared between all
68 * the PCI functions of a same device. Therefore, when the first
69 * function is probed by the driver, we can get an idea of the total
70 * count of desired actags for the device, and assign the actags to
71 * the AFUs, by pro-rating if needed.
72 */
73
74static int find_dvsec_from_pos(struct pci_dev *dev, int dvsec_id, int pos)
75{
76	int vsec = pos;
77	u16 vendor, id;
78
79	while ((vsec = pci_find_next_ext_capability(dev, vsec,
80						    OCXL_EXT_CAP_ID_DVSEC))) {
81		pci_read_config_word(dev, vsec + OCXL_DVSEC_VENDOR_OFFSET,
82				&vendor);
83		pci_read_config_word(dev, vsec + OCXL_DVSEC_ID_OFFSET, &id);
84		if (vendor == PCI_VENDOR_ID_IBM && id == dvsec_id)
85			return vsec;
86	}
87	return 0;
88}
89
90static int find_dvsec_afu_ctrl(struct pci_dev *dev, u8 afu_idx)
91{
92	int vsec = 0;
93	u8 idx;
94
95	while ((vsec = find_dvsec_from_pos(dev, OCXL_DVSEC_AFU_CTRL_ID,
96					   vsec))) {
97		pci_read_config_byte(dev, vsec + OCXL_DVSEC_AFU_CTRL_AFU_IDX,
98				&idx);
99		if (idx == afu_idx)
100			return vsec;
101	}
102	return 0;
103}
104
105static int get_max_afu_index(struct pci_dev *dev, int *afu_idx)
106{
107	int pos;
108	u32 val;
109
110	pos = pci_find_dvsec_capability(dev, PCI_VENDOR_ID_IBM,
111					OCXL_DVSEC_FUNC_ID);
112	if (!pos)
113		return -ESRCH;
114
115	pci_read_config_dword(dev, pos + OCXL_DVSEC_FUNC_OFF_INDEX, &val);
116	if (val & AFU_PRESENT)
117		*afu_idx = (val & AFU_INDEX_MASK) >> AFU_INDEX_SHIFT;
118	else
119		*afu_idx = -1;
120	return 0;
121}
122
123static int get_actag_count(struct pci_dev *dev, int afu_idx, int *actag)
124{
125	int pos;
126	u16 actag_sup;
127
128	pos = find_dvsec_afu_ctrl(dev, afu_idx);
129	if (!pos)
130		return -ESRCH;
131
132	pci_read_config_word(dev, pos + OCXL_DVSEC_AFU_CTRL_ACTAG_SUP,
133			&actag_sup);
134	*actag = actag_sup & ACTAG_MASK;
135	return 0;
136}
137
138static struct npu_link *find_link(struct pci_dev *dev)
139{
140	struct npu_link *link;
141
142	list_for_each_entry(link, &links_list, list) {
143		/* The functions of a device all share the same link */
144		if (link->domain == pci_domain_nr(dev->bus) &&
145			link->bus == dev->bus->number &&
146			link->dev == PCI_SLOT(dev->devfn)) {
147			return link;
148		}
149	}
150
151	/* link doesn't exist yet. Allocate one */
152	link = kzalloc(sizeof(struct npu_link), GFP_KERNEL);
153	if (!link)
154		return NULL;
155	link->domain = pci_domain_nr(dev->bus);
156	link->bus = dev->bus->number;
157	link->dev = PCI_SLOT(dev->devfn);
158	list_add(&link->list, &links_list);
159	return link;
160}
161
162static void pnv_ocxl_fixup_actag(struct pci_dev *dev)
163{
164	struct pci_controller *hose = pci_bus_to_host(dev->bus);
165	struct pnv_phb *phb = hose->private_data;
166	struct npu_link *link;
167	int rc, afu_idx = -1, i, actag;
168
169	if (!machine_is(powernv))
170		return;
171
172	if (phb->type != PNV_PHB_NPU_OCAPI)
173		return;
174
175	mutex_lock(&links_list_lock);
176
177	link = find_link(dev);
178	if (!link) {
179		dev_warn(&dev->dev, "couldn't update actag information\n");
180		mutex_unlock(&links_list_lock);
181		return;
182	}
183
184	/*
185	 * Check how many actags are desired for the AFUs under that
186	 * function and add it to the count for the link
187	 */
188	rc = get_max_afu_index(dev, &afu_idx);
189	if (rc) {
190		/* Most likely an invalid config space */
191		dev_dbg(&dev->dev, "couldn't find AFU information\n");
192		afu_idx = -1;
193	}
194
195	link->fn_desired_actags[PCI_FUNC(dev->devfn)] = 0;
196	for (i = 0; i <= afu_idx; i++) {
197		/*
198		 * AFU index 'holes' are allowed. So don't fail if we
199		 * can't read the actag info for an index
200		 */
201		rc = get_actag_count(dev, i, &actag);
202		if (rc)
203			continue;
204		link->fn_desired_actags[PCI_FUNC(dev->devfn)] += actag;
205	}
206	dev_dbg(&dev->dev, "total actags for function: %d\n",
207		link->fn_desired_actags[PCI_FUNC(dev->devfn)]);
208
209	mutex_unlock(&links_list_lock);
210}
211DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, pnv_ocxl_fixup_actag);
212
213static u16 assign_fn_actags(u16 desired, u16 total)
214{
215	u16 count;
216
217	if (total <= PNV_OCXL_ACTAG_MAX)
218		count = desired;
219	else
220		count = PNV_OCXL_ACTAG_MAX * desired / total;
221
222	return count;
223}
224
225static void assign_actags(struct npu_link *link)
226{
227	u16 actag_count, range_start = 0, total_desired = 0;
228	int i;
229
230	for (i = 0; i < 8; i++)
231		total_desired += link->fn_desired_actags[i];
232
233	for (i = 0; i < 8; i++) {
234		if (link->fn_desired_actags[i]) {
235			actag_count = assign_fn_actags(
236				link->fn_desired_actags[i],
237				total_desired);
238			link->fn_actags[i].start = range_start;
239			link->fn_actags[i].count = actag_count;
240			range_start += actag_count;
241			WARN_ON(range_start >= PNV_OCXL_ACTAG_MAX);
242		}
243		pr_debug("link %x:%x:%x fct %d actags: start=%d count=%d (desired=%d)\n",
244			link->domain, link->bus, link->dev, i,
245			link->fn_actags[i].start, link->fn_actags[i].count,
246			link->fn_desired_actags[i]);
247	}
248	link->assignment_done = true;
249}
250
251int pnv_ocxl_get_actag(struct pci_dev *dev, u16 *base, u16 *enabled,
252		u16 *supported)
253{
254	struct npu_link *link;
255
256	mutex_lock(&links_list_lock);
257
258	link = find_link(dev);
259	if (!link) {
260		dev_err(&dev->dev, "actag information not found\n");
261		mutex_unlock(&links_list_lock);
262		return -ENODEV;
263	}
264	/*
265	 * On p9, we only have 64 actags per link, so they must be
266	 * shared by all the functions of the same adapter. We counted
267	 * the desired actag counts during PCI enumeration, so that we
268	 * can allocate a pro-rated number of actags to each function.
269	 */
270	if (!link->assignment_done)
271		assign_actags(link);
272
273	*base      = link->fn_actags[PCI_FUNC(dev->devfn)].start;
274	*enabled   = link->fn_actags[PCI_FUNC(dev->devfn)].count;
275	*supported = link->fn_desired_actags[PCI_FUNC(dev->devfn)];
276
277	mutex_unlock(&links_list_lock);
278	return 0;
279}
280EXPORT_SYMBOL_GPL(pnv_ocxl_get_actag);
281
282int pnv_ocxl_get_pasid_count(struct pci_dev *dev, int *count)
283{
284	struct npu_link *link;
285	int i, rc = -EINVAL;
286
287	/*
288	 * The number of PASIDs (process address space ID) which can
289	 * be used by a function depends on how many functions exist
290	 * on the device. The NPU needs to be configured to know how
291	 * many bits are available to PASIDs and how many are to be
292	 * used by the function BDF identifier.
293	 *
294	 * We only support one AFU-carrying function for now.
295	 */
296	mutex_lock(&links_list_lock);
297
298	link = find_link(dev);
299	if (!link) {
300		dev_err(&dev->dev, "actag information not found\n");
301		mutex_unlock(&links_list_lock);
302		return -ENODEV;
303	}
304
305	for (i = 0; i < 8; i++)
306		if (link->fn_desired_actags[i] && (i == PCI_FUNC(dev->devfn))) {
307			*count = PNV_OCXL_PASID_MAX;
308			rc = 0;
309			break;
310		}
311
312	mutex_unlock(&links_list_lock);
313	dev_dbg(&dev->dev, "%d PASIDs available for function\n",
314		rc ? 0 : *count);
315	return rc;
316}
317EXPORT_SYMBOL_GPL(pnv_ocxl_get_pasid_count);
318
319static void set_templ_rate(unsigned int templ, unsigned int rate, char *buf)
320{
321	int shift, idx;
322
323	WARN_ON(templ > PNV_OCXL_TL_MAX_TEMPLATE);
324	idx = (PNV_OCXL_TL_MAX_TEMPLATE - templ) / 2;
325	shift = 4 * (1 - ((PNV_OCXL_TL_MAX_TEMPLATE - templ) % 2));
326	buf[idx] |= rate << shift;
327}
328
329int pnv_ocxl_get_tl_cap(struct pci_dev *dev, long *cap,
330			char *rate_buf, int rate_buf_size)
331{
332	if (rate_buf_size != PNV_OCXL_TL_RATE_BUF_SIZE)
333		return -EINVAL;
334	/*
335	 * The TL capabilities are a characteristic of the NPU, so
336	 * we go with hard-coded values.
337	 *
338	 * The receiving rate of each template is encoded on 4 bits.
339	 *
340	 * On P9:
341	 * - templates 0 -> 3 are supported
342	 * - templates 0, 1 and 3 have a 0 receiving rate
343	 * - template 2 has receiving rate of 1 (extra cycle)
344	 */
345	memset(rate_buf, 0, rate_buf_size);
346	set_templ_rate(2, 1, rate_buf);
347	*cap = PNV_OCXL_TL_P9_RECV_CAP;
348	return 0;
349}
350EXPORT_SYMBOL_GPL(pnv_ocxl_get_tl_cap);
351
352int pnv_ocxl_set_tl_conf(struct pci_dev *dev, long cap,
353			uint64_t rate_buf_phys, int rate_buf_size)
354{
355	struct pci_controller *hose = pci_bus_to_host(dev->bus);
356	struct pnv_phb *phb = hose->private_data;
357	int rc;
358
359	if (rate_buf_size != PNV_OCXL_TL_RATE_BUF_SIZE)
360		return -EINVAL;
361
362	rc = opal_npu_tl_set(phb->opal_id, dev->devfn, cap,
363			rate_buf_phys, rate_buf_size);
364	if (rc) {
365		dev_err(&dev->dev, "Can't configure host TL: %d\n", rc);
366		return -EINVAL;
367	}
368	return 0;
369}
370EXPORT_SYMBOL_GPL(pnv_ocxl_set_tl_conf);
371
372int pnv_ocxl_get_xsl_irq(struct pci_dev *dev, int *hwirq)
373{
374	int rc;
375
376	rc = of_property_read_u32(dev->dev.of_node, "ibm,opal-xsl-irq", hwirq);
377	if (rc) {
378		dev_err(&dev->dev,
379			"Can't get translation interrupt for device\n");
380		return rc;
381	}
382	return 0;
383}
384EXPORT_SYMBOL_GPL(pnv_ocxl_get_xsl_irq);
385
386void pnv_ocxl_unmap_xsl_regs(void __iomem *dsisr, void __iomem *dar,
387			void __iomem *tfc, void __iomem *pe_handle)
388{
389	iounmap(dsisr);
390	iounmap(dar);
391	iounmap(tfc);
392	iounmap(pe_handle);
393}
394EXPORT_SYMBOL_GPL(pnv_ocxl_unmap_xsl_regs);
395
396int pnv_ocxl_map_xsl_regs(struct pci_dev *dev, void __iomem **dsisr,
397			void __iomem **dar, void __iomem **tfc,
398			void __iomem **pe_handle)
399{
400	u64 reg;
401	int i, j, rc = 0;
402	void __iomem *regs[4];
403
404	/*
405	 * opal stores the mmio addresses of the DSISR, DAR, TFC and
406	 * PE_HANDLE registers in a device tree property, in that
407	 * order
408	 */
409	for (i = 0; i < 4; i++) {
410		rc = of_property_read_u64_index(dev->dev.of_node,
411						"ibm,opal-xsl-mmio", i, &reg);
412		if (rc)
413			break;
414		regs[i] = ioremap(reg, 8);
415		if (!regs[i]) {
416			rc = -EINVAL;
417			break;
418		}
419	}
420	if (rc) {
421		dev_err(&dev->dev, "Can't map translation mmio registers\n");
422		for (j = i - 1; j >= 0; j--)
423			iounmap(regs[j]);
424	} else {
425		*dsisr = regs[0];
426		*dar = regs[1];
427		*tfc = regs[2];
428		*pe_handle = regs[3];
429	}
430	return rc;
431}
432EXPORT_SYMBOL_GPL(pnv_ocxl_map_xsl_regs);
433
434struct spa_data {
435	u64 phb_opal_id;
436	u32 bdfn;
437};
438
439int pnv_ocxl_spa_setup(struct pci_dev *dev, void *spa_mem, int PE_mask,
440		void **platform_data)
441{
442	struct pci_controller *hose = pci_bus_to_host(dev->bus);
443	struct pnv_phb *phb = hose->private_data;
444	struct spa_data *data;
445	u32 bdfn;
446	int rc;
447
448	data = kzalloc(sizeof(*data), GFP_KERNEL);
449	if (!data)
450		return -ENOMEM;
451
452	bdfn = pci_dev_id(dev);
453	rc = opal_npu_spa_setup(phb->opal_id, bdfn, virt_to_phys(spa_mem),
454				PE_mask);
455	if (rc) {
456		dev_err(&dev->dev, "Can't setup Shared Process Area: %d\n", rc);
457		kfree(data);
458		return rc;
459	}
460	data->phb_opal_id = phb->opal_id;
461	data->bdfn = bdfn;
462	*platform_data = (void *) data;
463	return 0;
464}
465EXPORT_SYMBOL_GPL(pnv_ocxl_spa_setup);
466
467void pnv_ocxl_spa_release(void *platform_data)
468{
469	struct spa_data *data = (struct spa_data *) platform_data;
470	int rc;
471
472	rc = opal_npu_spa_setup(data->phb_opal_id, data->bdfn, 0, 0);
473	WARN_ON(rc);
474	kfree(data);
475}
476EXPORT_SYMBOL_GPL(pnv_ocxl_spa_release);
477
478int pnv_ocxl_spa_remove_pe_from_cache(void *platform_data, int pe_handle)
479{
480	struct spa_data *data = (struct spa_data *) platform_data;
481
482	return opal_npu_spa_clear_cache(data->phb_opal_id, data->bdfn, pe_handle);
483}
484EXPORT_SYMBOL_GPL(pnv_ocxl_spa_remove_pe_from_cache);
485
486int pnv_ocxl_map_lpar(struct pci_dev *dev, uint64_t lparid,
487		      uint64_t lpcr, void __iomem **arva)
488{
489	struct pci_controller *hose = pci_bus_to_host(dev->bus);
490	struct pnv_phb *phb = hose->private_data;
491	u64 mmio_atsd;
492	int rc;
493
494	/* ATSD physical address.
495	 * ATSD LAUNCH register: write access initiates a shoot down to
496	 * initiate the TLB Invalidate command.
497	 */
498	rc = of_property_read_u64_index(hose->dn, "ibm,mmio-atsd",
499					0, &mmio_atsd);
500	if (rc) {
501		dev_info(&dev->dev, "No available ATSD found\n");
502		return rc;
503	}
504
505	/* Assign a register set to a Logical Partition and MMIO ATSD
506	 * LPARID register to the required value.
507	 */
508	rc = opal_npu_map_lpar(phb->opal_id, pci_dev_id(dev),
509			       lparid, lpcr);
510	if (rc) {
511		dev_err(&dev->dev, "Error mapping device to LPAR: %d\n", rc);
512		return rc;
513	}
514
515	*arva = ioremap(mmio_atsd, 24);
516	if (!(*arva)) {
517		dev_warn(&dev->dev, "ioremap failed - mmio_atsd: %#llx\n", mmio_atsd);
518		rc = -ENOMEM;
519	}
520
521	return rc;
522}
523EXPORT_SYMBOL_GPL(pnv_ocxl_map_lpar);
524
525void pnv_ocxl_unmap_lpar(void __iomem *arva)
526{
527	iounmap(arva);
528}
529EXPORT_SYMBOL_GPL(pnv_ocxl_unmap_lpar);
530
531void pnv_ocxl_tlb_invalidate(void __iomem *arva,
532			     unsigned long pid,
533			     unsigned long addr,
534			     unsigned long page_size)
535{
536	unsigned long timeout = jiffies + (HZ * PNV_OCXL_ATSD_TIMEOUT);
537	u64 val = 0ull;
538	int pend;
539	u8 size;
540
541	if (!(arva))
542		return;
543
544	if (addr) {
545		/* load Abbreviated Virtual Address register with
546		 * the necessary value
547		 */
548		val |= FIELD_PREP(PNV_OCXL_ATSD_AVA_AVA, addr >> (63-51));
549		out_be64(arva + PNV_OCXL_ATSD_AVA, val);
550	}
551
552	/* Write access initiates a shoot down to initiate the
553	 * TLB Invalidate command
554	 */
555	val = PNV_OCXL_ATSD_LNCH_R;
556	val |= FIELD_PREP(PNV_OCXL_ATSD_LNCH_RIC, 0b10);
557	if (addr)
558		val |= FIELD_PREP(PNV_OCXL_ATSD_LNCH_IS, 0b00);
559	else {
560		val |= FIELD_PREP(PNV_OCXL_ATSD_LNCH_IS, 0b01);
561		val |= PNV_OCXL_ATSD_LNCH_OCAPI_SINGLETON;
562	}
563	val |= PNV_OCXL_ATSD_LNCH_PRS;
564	/* Actual Page Size to be invalidated
565	 * 000 4KB
566	 * 101 64KB
567	 * 001 2MB
568	 * 010 1GB
569	 */
570	size = 0b101;
571	if (page_size == 0x1000)
572		size = 0b000;
573	if (page_size == 0x200000)
574		size = 0b001;
575	if (page_size == 0x40000000)
576		size = 0b010;
577	val |= FIELD_PREP(PNV_OCXL_ATSD_LNCH_AP, size);
578	val |= FIELD_PREP(PNV_OCXL_ATSD_LNCH_PID, pid);
579	out_be64(arva + PNV_OCXL_ATSD_LNCH, val);
580
581	/* Poll the ATSD status register to determine when the
582	 * TLB Invalidate has been completed.
583	 */
584	val = in_be64(arva + PNV_OCXL_ATSD_STAT);
585	pend = val >> 63;
586
587	while (pend) {
588		if (time_after_eq(jiffies, timeout)) {
589			pr_err("%s - Timeout while reading XTS MMIO ATSD status register (val=%#llx, pidr=0x%lx)\n",
590			       __func__, val, pid);
591			return;
592		}
593		cpu_relax();
594		val = in_be64(arva + PNV_OCXL_ATSD_STAT);
595		pend = val >> 63;
596	}
597}
598EXPORT_SYMBOL_GPL(pnv_ocxl_tlb_invalidate);
599