1// SPDX-License-Identifier: GPL-2.0+
2// Copyright 2017 IBM Corp.
3#ifndef _MISC_OCXL_H_
4#define _MISC_OCXL_H_
5
6#include <linux/pci.h>
7
8/*
9 * Opencapi drivers all need some common facilities, like parsing the
10 * device configuration space, adding a Process Element to the Shared
11 * Process Area, etc...
12 *
13 * The ocxl module provides a kernel API, to allow other drivers to
14 * reuse common code. A bit like a in-kernel library.
15 */
16
17#define OCXL_AFU_NAME_SZ (24+1) /* add 1 for NULL termination */
18
19
20struct ocxl_afu_config {
21 u8 idx;
22 int dvsec_afu_control_pos; /* offset of AFU control DVSEC */
23 char name[OCXL_AFU_NAME_SZ];
24 u8 version_major;
25 u8 version_minor;
26 u8 afuc_type;
27 u8 afum_type;
28 u8 profile;
29 u8 global_mmio_bar; /* global MMIO area */
30 u64 global_mmio_offset;
31 u32 global_mmio_size;
32 u8 pp_mmio_bar; /* per-process MMIO area */
33 u64 pp_mmio_offset;
34 u32 pp_mmio_stride;
35 u64 lpc_mem_offset;
36 u64 lpc_mem_size;
37 u64 special_purpose_mem_offset;
38 u64 special_purpose_mem_size;
39 u8 pasid_supported_log;
40 u16 actag_supported;
41};
42
43struct ocxl_fn_config {
44 int dvsec_tl_pos; /* offset of the Transaction Layer DVSEC */
45 int dvsec_function_pos; /* offset of the Function DVSEC */
46 int dvsec_afu_info_pos; /* offset of the AFU information DVSEC */
47 s8 max_pasid_log;
48 s8 max_afu_index;
49};
50
51enum ocxl_endian {
52 OCXL_BIG_ENDIAN = 0, /**< AFU data is big-endian */
53 OCXL_LITTLE_ENDIAN = 1, /**< AFU data is little-endian */
54 OCXL_HOST_ENDIAN = 2, /**< AFU data is the same endianness as the host */
55};
56
57// These are opaque outside the ocxl driver
58struct ocxl_afu;
59struct ocxl_fn;
60struct ocxl_context;
61
62// Device detection & initialisation
63
64/**
65 * ocxl_function_open() - Open an OpenCAPI function on an OpenCAPI device
66 * @dev: The PCI device that contains the function
67 *
68 * Returns an opaque pointer to the function, or an error pointer (check with IS_ERR)
69 */
70struct ocxl_fn *ocxl_function_open(struct pci_dev *dev);
71
72/**
73 * ocxl_function_afu_list() - Get the list of AFUs associated with a PCI function device
74 * Returns a list of struct ocxl_afu *
75 *
76 * @fn: The OpenCAPI function containing the AFUs
77 */
78struct list_head *ocxl_function_afu_list(struct ocxl_fn *fn);
79
80/**
81 * ocxl_function_fetch_afu() - Fetch an AFU instance from an OpenCAPI function
82 * @fn: The OpenCAPI function to get the AFU from
83 * @afu_idx: The index of the AFU to get
84 *
85 * If successful, the AFU should be released with ocxl_afu_put()
86 *
87 * Returns a pointer to the AFU, or NULL on error
88 */
89struct ocxl_afu *ocxl_function_fetch_afu(struct ocxl_fn *fn, u8 afu_idx);
90
91/**
92 * ocxl_afu_get() - Take a reference to an AFU
93 * @afu: The AFU to increment the reference count on
94 */
95void ocxl_afu_get(struct ocxl_afu *afu);
96
97/**
98 * ocxl_afu_put() - Release a reference to an AFU
99 * @afu: The AFU to decrement the reference count on
100 */
101void ocxl_afu_put(struct ocxl_afu *afu);
102
103
104/**
105 * ocxl_function_config() - Get the configuration information for an OpenCAPI function
106 * @fn: The OpenCAPI function to get the config for
107 *
108 * Returns the function config, or NULL on error
109 */
110const struct ocxl_fn_config *ocxl_function_config(struct ocxl_fn *fn);
111
112/**
113 * ocxl_function_close() - Close an OpenCAPI function
114 * This will free any AFUs previously retrieved from the function, and
115 * detach and associated contexts. The contexts must by freed by the caller.
116 *
117 * @fn: The OpenCAPI function to close
118 *
119 */
120void ocxl_function_close(struct ocxl_fn *fn);
121
122// Context allocation
123
124/**
125 * ocxl_context_alloc() - Allocate an OpenCAPI context
126 * @context: The OpenCAPI context to allocate, must be freed with ocxl_context_free
127 * @afu: The AFU the context belongs to
128 * @mapping: The mapping to unmap when the context is closed (may be NULL)
129 */
130int ocxl_context_alloc(struct ocxl_context **context, struct ocxl_afu *afu,
131 struct address_space *mapping);
132
133/**
134 * ocxl_context_free() - Free an OpenCAPI context
135 * @ctx: The OpenCAPI context to free
136 */
137void ocxl_context_free(struct ocxl_context *ctx);
138
139/**
140 * ocxl_context_attach() - Grant access to an MM to an OpenCAPI context
141 * @ctx: The OpenCAPI context to attach
142 * @amr: The value of the AMR register to restrict access
143 * @mm: The mm to attach to the context
144 *
145 * Returns 0 on success, negative on failure
146 */
147int ocxl_context_attach(struct ocxl_context *ctx, u64 amr,
148 struct mm_struct *mm);
149
150/**
151 * ocxl_context_detach() - Detach an MM from an OpenCAPI context
152 * @ctx: The OpenCAPI context to attach
153 *
154 * Returns 0 on success, negative on failure
155 */
156int ocxl_context_detach(struct ocxl_context *ctx);
157
158// AFU IRQs
159
160/**
161 * ocxl_afu_irq_alloc() - Allocate an IRQ associated with an AFU context
162 * @ctx: the AFU context
163 * @irq_id: out, the IRQ ID
164 *
165 * Returns 0 on success, negative on failure
166 */
167int ocxl_afu_irq_alloc(struct ocxl_context *ctx, int *irq_id);
168
169/**
170 * ocxl_afu_irq_free() - Frees an IRQ associated with an AFU context
171 * @ctx: the AFU context
172 * @irq_id: the IRQ ID
173 *
174 * Returns 0 on success, negative on failure
175 */
176int ocxl_afu_irq_free(struct ocxl_context *ctx, int irq_id);
177
178/**
179 * ocxl_afu_irq_get_addr() - Gets the address of the trigger page for an IRQ
180 * This can then be provided to an AFU which will write to that
181 * page to trigger the IRQ.
182 * @ctx: The AFU context that the IRQ is associated with
183 * @irq_id: The IRQ ID
184 *
185 * returns the trigger page address, or 0 if the IRQ is not valid
186 */
187u64 ocxl_afu_irq_get_addr(struct ocxl_context *ctx, int irq_id);
188
189/**
190 * ocxl_irq_set_handler() - Provide a callback to be called when an IRQ is triggered
191 * @ctx: The AFU context that the IRQ is associated with
192 * @irq_id: The IRQ ID
193 * @handler: the callback to be called when the IRQ is triggered
194 * @free_private: the callback to be called when the IRQ is freed (may be NULL)
195 * @private: Private data to be passed to the callbacks
196 *
197 * Returns 0 on success, negative on failure
198 */
199int ocxl_irq_set_handler(struct ocxl_context *ctx, int irq_id,
200 irqreturn_t (*handler)(void *private),
201 void (*free_private)(void *private),
202 void *private);
203
204// AFU Metadata
205
206/**
207 * ocxl_afu_config() - Get a pointer to the config for an AFU
208 * @afu: a pointer to the AFU to get the config for
209 *
210 * Returns a pointer to the AFU config
211 */
212struct ocxl_afu_config *ocxl_afu_config(struct ocxl_afu *afu);
213
214/**
215 * ocxl_afu_set_private() - Assign opaque hardware specific information to an OpenCAPI AFU.
216 * @afu: The OpenCAPI AFU
217 * @private: the opaque hardware specific information to assign to the driver
218 */
219void ocxl_afu_set_private(struct ocxl_afu *afu, void *private);
220
221/**
222 * ocxl_afu_get_private() - Fetch the hardware specific information associated with
223 * an external OpenCAPI AFU. This may be consumed by an external OpenCAPI driver.
224 * @afu: The OpenCAPI AFU
225 *
226 * Returns the opaque pointer associated with the device, or NULL if not set
227 */
228void *ocxl_afu_get_private(struct ocxl_afu *afu);
229
230// Global MMIO
231/**
232 * ocxl_global_mmio_read32() - Read a 32 bit value from global MMIO
233 * @afu: The AFU
234 * @offset: The Offset from the start of MMIO
235 * @endian: the endianness that the MMIO data is in
236 * @val: returns the value
237 *
238 * Returns 0 for success, negative on error
239 */
240int ocxl_global_mmio_read32(struct ocxl_afu *afu, size_t offset,
241 enum ocxl_endian endian, u32 *val);
242
243/**
244 * ocxl_global_mmio_read64() - Read a 64 bit value from global MMIO
245 * @afu: The AFU
246 * @offset: The Offset from the start of MMIO
247 * @endian: the endianness that the MMIO data is in
248 * @val: returns the value
249 *
250 * Returns 0 for success, negative on error
251 */
252int ocxl_global_mmio_read64(struct ocxl_afu *afu, size_t offset,
253 enum ocxl_endian endian, u64 *val);
254
255/**
256 * ocxl_global_mmio_write32() - Write a 32 bit value to global MMIO
257 * @afu: The AFU
258 * @offset: The Offset from the start of MMIO
259 * @endian: the endianness that the MMIO data is in
260 * @val: The value to write
261 *
262 * Returns 0 for success, negative on error
263 */
264int ocxl_global_mmio_write32(struct ocxl_afu *afu, size_t offset,
265 enum ocxl_endian endian, u32 val);
266
267/**
268 * ocxl_global_mmio_write64() - Write a 64 bit value to global MMIO
269 * @afu: The AFU
270 * @offset: The Offset from the start of MMIO
271 * @endian: the endianness that the MMIO data is in
272 * @val: The value to write
273 *
274 * Returns 0 for success, negative on error
275 */
276int ocxl_global_mmio_write64(struct ocxl_afu *afu, size_t offset,
277 enum ocxl_endian endian, u64 val);
278
279/**
280 * ocxl_global_mmio_set32() - Set bits in a 32 bit global MMIO register
281 * @afu: The AFU
282 * @offset: The Offset from the start of MMIO
283 * @endian: the endianness that the MMIO data is in
284 * @mask: a mask of the bits to set
285 *
286 * Returns 0 for success, negative on error
287 */
288int ocxl_global_mmio_set32(struct ocxl_afu *afu, size_t offset,
289 enum ocxl_endian endian, u32 mask);
290
291/**
292 * ocxl_global_mmio_set64() - Set bits in a 64 bit global MMIO register
293 * @afu: The AFU
294 * @offset: The Offset from the start of MMIO
295 * @endian: the endianness that the MMIO data is in
296 * @mask: a mask of the bits to set
297 *
298 * Returns 0 for success, negative on error
299 */
300int ocxl_global_mmio_set64(struct ocxl_afu *afu, size_t offset,
301 enum ocxl_endian endian, u64 mask);
302
303/**
304 * ocxl_global_mmio_clear32() - Set bits in a 32 bit global MMIO register
305 * @afu: The AFU
306 * @offset: The Offset from the start of MMIO
307 * @endian: the endianness that the MMIO data is in
308 * @mask: a mask of the bits to set
309 *
310 * Returns 0 for success, negative on error
311 */
312int ocxl_global_mmio_clear32(struct ocxl_afu *afu, size_t offset,
313 enum ocxl_endian endian, u32 mask);
314
315/**
316 * ocxl_global_mmio_clear64() - Set bits in a 64 bit global MMIO register
317 * @afu: The AFU
318 * @offset: The Offset from the start of MMIO
319 * @endian: the endianness that the MMIO data is in
320 * @mask: a mask of the bits to set
321 *
322 * Returns 0 for success, negative on error
323 */
324int ocxl_global_mmio_clear64(struct ocxl_afu *afu, size_t offset,
325 enum ocxl_endian endian, u64 mask);
326
327// Functions left here are for compatibility with the cxlflash driver
328
329/*
330 * Read the configuration space of a function for the AFU specified by
331 * the index 'afu_idx'. Fills in a ocxl_afu_config structure
332 */
333int ocxl_config_read_afu(struct pci_dev *dev,
334 struct ocxl_fn_config *fn,
335 struct ocxl_afu_config *afu,
336 u8 afu_idx);
337
338/*
339 * Tell an AFU, by writing in the configuration space, the PASIDs that
340 * it can use. Range starts at 'pasid_base' and its size is a multiple
341 * of 2
342 *
343 * 'afu_control_offset' is the offset of the AFU control DVSEC which
344 * can be found in the function configuration
345 */
346void ocxl_config_set_afu_pasid(struct pci_dev *dev,
347 int afu_control_offset,
348 int pasid_base, u32 pasid_count_log);
349
350/*
351 * Get the actag configuration for the function:
352 * 'base' is the first actag value that can be used.
353 * 'enabled' it the number of actags available, starting from base.
354 * 'supported' is the total number of actags desired by all the AFUs
355 * of the function.
356 */
357int ocxl_config_get_actag_info(struct pci_dev *dev,
358 u16 *base, u16 *enabled, u16 *supported);
359
360/*
361 * Tell a function, by writing in the configuration space, the actags
362 * it can use.
363 *
364 * 'func_offset' is the offset of the Function DVSEC that can found in
365 * the function configuration
366 */
367void ocxl_config_set_actag(struct pci_dev *dev, int func_offset,
368 u32 actag_base, u32 actag_count);
369
370/*
371 * Tell an AFU, by writing in the configuration space, the actags it
372 * can use.
373 *
374 * 'afu_control_offset' is the offset of the AFU control DVSEC for the
375 * desired AFU. It can be found in the AFU configuration
376 */
377void ocxl_config_set_afu_actag(struct pci_dev *dev,
378 int afu_control_offset,
379 int actag_base, int actag_count);
380
381/*
382 * Enable/disable an AFU, by writing in the configuration space.
383 *
384 * 'afu_control_offset' is the offset of the AFU control DVSEC for the
385 * desired AFU. It can be found in the AFU configuration
386 */
387void ocxl_config_set_afu_state(struct pci_dev *dev,
388 int afu_control_offset, int enable);
389
390/*
391 * Set the Transaction Layer configuration in the configuration space.
392 * Only needed for function 0.
393 *
394 * It queries the host TL capabilities, find some common ground
395 * between the host and device, and set the Transaction Layer on both
396 * accordingly.
397 */
398int ocxl_config_set_TL(struct pci_dev *dev, int tl_dvsec);
399
400/*
401 * Request an AFU to terminate a PASID.
402 * Will return once the AFU has acked the request, or an error in case
403 * of timeout.
404 *
405 * The hardware can only terminate one PASID at a time, so caller must
406 * guarantee some kind of serialization.
407 *
408 * 'afu_control_offset' is the offset of the AFU control DVSEC for the
409 * desired AFU. It can be found in the AFU configuration
410 */
411int ocxl_config_terminate_pasid(struct pci_dev *dev,
412 int afu_control_offset, int pasid);
413
414/*
415 * Read the configuration space of a function and fill in a
416 * ocxl_fn_config structure with all the function details
417 */
418int ocxl_config_read_function(struct pci_dev *dev,
419 struct ocxl_fn_config *fn);
420
421/*
422 * Set up the opencapi link for the function.
423 *
424 * When called for the first time for a link, it sets up the Shared
425 * Process Area for the link and the interrupt handler to process
426 * translation faults.
427 *
428 * Returns a 'link handle' that should be used for further calls for
429 * the link
430 */
431int ocxl_link_setup(struct pci_dev *dev, int PE_mask,
432 void **link_handle);
433
434/*
435 * Remove the association between the function and its link.
436 */
437void ocxl_link_release(struct pci_dev *dev, void *link_handle);
438
439/*
440 * Add a Process Element to the Shared Process Area for a link.
441 * The process is defined by its PASID, pid, tid and its mm_struct.
442 *
443 * 'xsl_err_cb' is an optional callback if the driver wants to be
444 * notified when the translation fault interrupt handler detects an
445 * address error.
446 * 'xsl_err_data' is an argument passed to the above callback, if
447 * defined
448 */
449int ocxl_link_add_pe(void *link_handle, int pasid, u32 pidr, u32 tidr,
450 u64 amr, u16 bdf, struct mm_struct *mm,
451 void (*xsl_err_cb)(void *data, u64 addr, u64 dsisr),
452 void *xsl_err_data);
453
454/*
455 * Remove a Process Element from the Shared Process Area for a link
456 */
457int ocxl_link_remove_pe(void *link_handle, int pasid);
458
459/*
460 * Allocate an AFU interrupt associated to the link.
461 *
462 * 'hw_irq' is the hardware interrupt number
463 */
464int ocxl_link_irq_alloc(void *link_handle, int *hw_irq);
465
466/*
467 * Free a previously allocated AFU interrupt
468 */
469void ocxl_link_free_irq(void *link_handle, int hw_irq);
470
471#endif /* _MISC_OCXL_H_ */
472

source code of linux/include/misc/ocxl.h