2 * Copyright 2014 IBM Corp.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
10 #include <linux/spinlock.h>
11 #include <linux/module.h>
12 #include <linux/export.h>
13 #include <linux/kernel.h>
14 #include <linux/bitmap.h>
15 #include <linux/sched.h>
16 #include <linux/poll.h>
17 #include <linux/pid.h>
20 #include <linux/slab.h>
21 #include <asm/cputable.h>
22 #include <asm/current.h>
23 #include <asm/copro.h>
27 #define CXL_NUM_MINORS 256 /* Total to reserve */
28 #define CXL_DEV_MINORS 13 /* 1 control + 4 AFUs * 3 (dedicated/master/shared) */
30 #define CXL_CARD_MINOR(adapter) (adapter->adapter_num * CXL_DEV_MINORS)
31 #define CXL_AFU_MINOR_D(afu) (CXL_CARD_MINOR(afu->adapter) + 1 + (3 * afu->slice))
32 #define CXL_AFU_MINOR_M(afu) (CXL_AFU_MINOR_D(afu) + 1)
33 #define CXL_AFU_MINOR_S(afu) (CXL_AFU_MINOR_D(afu) + 2)
34 #define CXL_AFU_MKDEV_D(afu) MKDEV(MAJOR(cxl_dev), CXL_AFU_MINOR_D(afu))
35 #define CXL_AFU_MKDEV_M(afu) MKDEV(MAJOR(cxl_dev), CXL_AFU_MINOR_M(afu))
36 #define CXL_AFU_MKDEV_S(afu) MKDEV(MAJOR(cxl_dev), CXL_AFU_MINOR_S(afu))
38 #define CXL_DEVT_ADAPTER(dev) (MINOR(dev) / CXL_DEV_MINORS)
39 #define CXL_DEVT_AFU(dev) ((MINOR(dev) % CXL_DEV_MINORS - 1) / 3)
41 #define CXL_DEVT_IS_CARD(dev) (MINOR(dev) % CXL_DEV_MINORS == 0)
45 static struct class *cxl_class
;
47 static int __afu_open(struct inode
*inode
, struct file
*file
, bool master
)
51 struct cxl_context
*ctx
;
52 int adapter_num
= CXL_DEVT_ADAPTER(inode
->i_rdev
);
53 int slice
= CXL_DEVT_AFU(inode
->i_rdev
);
56 pr_devel("afu_open afu%i.%i\n", slice
, adapter_num
);
58 if (!(adapter
= get_cxl_adapter(adapter_num
)))
61 if (slice
> adapter
->slices
)
64 spin_lock(&adapter
->afu_list_lock
);
65 if (!(afu
= adapter
->afu
[slice
])) {
66 spin_unlock(&adapter
->afu_list_lock
);
69 get_device(&afu
->dev
);
70 spin_unlock(&adapter
->afu_list_lock
);
72 if (!afu
->current_mode
)
75 if (!(ctx
= cxl_context_alloc())) {
80 if ((rc
= cxl_context_init(ctx
, afu
, master
)))
83 pr_devel("afu_open pe: %i\n", ctx
->pe
);
84 file
->private_data
= ctx
;
87 /* Our ref on the AFU will now hold the adapter */
88 put_device(&adapter
->dev
);
93 put_device(&afu
->dev
);
95 put_device(&adapter
->dev
);
98 static int afu_open(struct inode
*inode
, struct file
*file
)
100 return __afu_open(inode
, file
, false);
103 static int afu_master_open(struct inode
*inode
, struct file
*file
)
105 return __afu_open(inode
, file
, true);
108 static int afu_release(struct inode
*inode
, struct file
*file
)
110 struct cxl_context
*ctx
= file
->private_data
;
112 pr_devel("%s: closing cxl file descriptor. pe: %i\n",
114 cxl_context_detach(ctx
);
116 put_device(&ctx
->afu
->dev
);
119 * At this this point all bottom halfs have finished and we should be
120 * getting no more IRQs from the hardware for this context. Once it's
121 * removed from the IDR (and RCU synchronised) it's safe to free the
124 cxl_context_free(ctx
);
130 static long afu_ioctl_start_work(struct cxl_context
*ctx
,
131 struct cxl_ioctl_start_work __user
*uwork
)
133 struct cxl_ioctl_start_work work
;
137 pr_devel("%s: pe: %i\n", __func__
, ctx
->pe
);
139 mutex_lock(&ctx
->status_mutex
);
140 if (ctx
->status
!= OPENED
) {
145 if (copy_from_user(&work
, uwork
,
146 sizeof(struct cxl_ioctl_start_work
))) {
152 * if any of the reserved fields are set or any of the unused
153 * flags are set it's invalid
155 if (work
.reserved1
|| work
.reserved2
|| work
.reserved3
||
156 work
.reserved4
|| work
.reserved5
|| work
.reserved6
||
157 (work
.flags
& ~CXL_START_WORK_ALL
)) {
162 if (!(work
.flags
& CXL_START_WORK_NUM_IRQS
))
163 work
.num_interrupts
= ctx
->afu
->pp_irqs
;
164 else if ((work
.num_interrupts
< ctx
->afu
->pp_irqs
) ||
165 (work
.num_interrupts
> ctx
->afu
->irqs_max
)) {
169 if ((rc
= afu_register_irqs(ctx
, work
.num_interrupts
)))
172 if (work
.flags
& CXL_START_WORK_AMR
)
173 amr
= work
.amr
& mfspr(SPRN_UAMOR
);
176 * We grab the PID here and not in the file open to allow for the case
177 * where a process (master, some daemon, etc) has opened the chardev on
178 * behalf of another process, so the AFU's mm gets bound to the process
179 * that performs this ioctl and not the process that opened the file.
181 ctx
->pid
= get_pid(get_task_pid(current
, PIDTYPE_PID
));
183 if ((rc
= cxl_attach_process(ctx
, false, work
.work_element_descriptor
,
187 ctx
->status
= STARTED
;
190 mutex_unlock(&ctx
->status_mutex
);
193 static long afu_ioctl_process_element(struct cxl_context
*ctx
,
196 pr_devel("%s: pe: %i\n", __func__
, ctx
->pe
);
198 if (copy_to_user(upe
, &ctx
->pe
, sizeof(__u32
)))
204 static long afu_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
206 struct cxl_context
*ctx
= file
->private_data
;
208 if (ctx
->status
== CLOSED
)
211 pr_devel("afu_ioctl\n");
213 case CXL_IOCTL_START_WORK
:
214 return afu_ioctl_start_work(ctx
, (struct cxl_ioctl_start_work __user
*)arg
);
215 case CXL_IOCTL_GET_PROCESS_ELEMENT
:
216 return afu_ioctl_process_element(ctx
, (__u32 __user
*)arg
);
221 static long afu_compat_ioctl(struct file
*file
, unsigned int cmd
,
224 return afu_ioctl(file
, cmd
, arg
);
227 static int afu_mmap(struct file
*file
, struct vm_area_struct
*vm
)
229 struct cxl_context
*ctx
= file
->private_data
;
231 /* AFU must be started before we can MMIO */
232 if (ctx
->status
!= STARTED
)
235 return cxl_context_iomap(ctx
, vm
);
238 static unsigned int afu_poll(struct file
*file
, struct poll_table_struct
*poll
)
240 struct cxl_context
*ctx
= file
->private_data
;
245 poll_wait(file
, &ctx
->wq
, poll
);
247 pr_devel("afu_poll wait done pe: %i\n", ctx
->pe
);
249 spin_lock_irqsave(&ctx
->lock
, flags
);
250 if (ctx
->pending_irq
|| ctx
->pending_fault
||
251 ctx
->pending_afu_err
)
252 mask
|= POLLIN
| POLLRDNORM
;
253 else if (ctx
->status
== CLOSED
)
254 /* Only error on closed when there are no futher events pending
257 spin_unlock_irqrestore(&ctx
->lock
, flags
);
259 pr_devel("afu_poll pe: %i returning %#x\n", ctx
->pe
, mask
);
264 static inline int ctx_event_pending(struct cxl_context
*ctx
)
266 return (ctx
->pending_irq
|| ctx
->pending_fault
||
267 ctx
->pending_afu_err
|| (ctx
->status
== CLOSED
));
270 static ssize_t
afu_read(struct file
*file
, char __user
*buf
, size_t count
,
273 struct cxl_context
*ctx
= file
->private_data
;
274 struct cxl_event event
;
279 if (count
< CXL_READ_MIN_SIZE
)
282 spin_lock_irqsave(&ctx
->lock
, flags
);
285 prepare_to_wait(&ctx
->wq
, &wait
, TASK_INTERRUPTIBLE
);
286 if (ctx_event_pending(ctx
))
289 if (file
->f_flags
& O_NONBLOCK
) {
294 if (signal_pending(current
)) {
299 spin_unlock_irqrestore(&ctx
->lock
, flags
);
300 pr_devel("afu_read going to sleep...\n");
302 pr_devel("afu_read woken up\n");
303 spin_lock_irqsave(&ctx
->lock
, flags
);
306 finish_wait(&ctx
->wq
, &wait
);
308 memset(&event
, 0, sizeof(event
));
309 event
.header
.process_element
= ctx
->pe
;
310 event
.header
.size
= sizeof(struct cxl_event_header
);
311 if (ctx
->pending_irq
) {
312 pr_devel("afu_read delivering AFU interrupt\n");
313 event
.header
.size
+= sizeof(struct cxl_event_afu_interrupt
);
314 event
.header
.type
= CXL_EVENT_AFU_INTERRUPT
;
315 event
.irq
.irq
= find_first_bit(ctx
->irq_bitmap
, ctx
->irq_count
) + 1;
316 clear_bit(event
.irq
.irq
- 1, ctx
->irq_bitmap
);
317 if (bitmap_empty(ctx
->irq_bitmap
, ctx
->irq_count
))
318 ctx
->pending_irq
= false;
319 } else if (ctx
->pending_fault
) {
320 pr_devel("afu_read delivering data storage fault\n");
321 event
.header
.size
+= sizeof(struct cxl_event_data_storage
);
322 event
.header
.type
= CXL_EVENT_DATA_STORAGE
;
323 event
.fault
.addr
= ctx
->fault_addr
;
324 event
.fault
.dsisr
= ctx
->fault_dsisr
;
325 ctx
->pending_fault
= false;
326 } else if (ctx
->pending_afu_err
) {
327 pr_devel("afu_read delivering afu error\n");
328 event
.header
.size
+= sizeof(struct cxl_event_afu_error
);
329 event
.header
.type
= CXL_EVENT_AFU_ERROR
;
330 event
.afu_error
.error
= ctx
->afu_err
;
331 ctx
->pending_afu_err
= false;
332 } else if (ctx
->status
== CLOSED
) {
333 pr_devel("afu_read fatal error\n");
334 spin_unlock_irqrestore(&ctx
->lock
, flags
);
337 WARN(1, "afu_read must be buggy\n");
339 spin_unlock_irqrestore(&ctx
->lock
, flags
);
341 if (copy_to_user(buf
, &event
, event
.header
.size
))
343 return event
.header
.size
;
346 finish_wait(&ctx
->wq
, &wait
);
347 spin_unlock_irqrestore(&ctx
->lock
, flags
);
351 static const struct file_operations afu_fops
= {
352 .owner
= THIS_MODULE
,
356 .release
= afu_release
,
357 .unlocked_ioctl
= afu_ioctl
,
358 .compat_ioctl
= afu_compat_ioctl
,
362 static const struct file_operations afu_master_fops
= {
363 .owner
= THIS_MODULE
,
364 .open
= afu_master_open
,
367 .release
= afu_release
,
368 .unlocked_ioctl
= afu_ioctl
,
369 .compat_ioctl
= afu_compat_ioctl
,
374 static char *cxl_devnode(struct device
*dev
, umode_t
*mode
)
376 if (CXL_DEVT_IS_CARD(dev
->devt
)) {
378 * These minor numbers will eventually be used to program the
379 * PSL and AFUs once we have dynamic reprogramming support
383 return kasprintf(GFP_KERNEL
, "cxl/%s", dev_name(dev
));
386 extern struct class *cxl_class
;
388 static int cxl_add_chardev(struct cxl_afu
*afu
, dev_t devt
, struct cdev
*cdev
,
389 struct device
**chardev
, char *postfix
, char *desc
,
390 const struct file_operations
*fops
)
395 cdev_init(cdev
, fops
);
396 if ((rc
= cdev_add(cdev
, devt
, 1))) {
397 dev_err(&afu
->dev
, "Unable to add %s chardev: %i\n", desc
, rc
);
401 dev
= device_create(cxl_class
, &afu
->dev
, devt
, afu
,
402 "afu%i.%i%s", afu
->adapter
->adapter_num
, afu
->slice
, postfix
);
404 dev_err(&afu
->dev
, "Unable to create %s chardev in sysfs: %i\n", desc
, rc
);
417 int cxl_chardev_d_afu_add(struct cxl_afu
*afu
)
419 return cxl_add_chardev(afu
, CXL_AFU_MKDEV_D(afu
), &afu
->afu_cdev_d
,
420 &afu
->chardev_d
, "d", "dedicated",
421 &afu_master_fops
); /* Uses master fops */
424 int cxl_chardev_m_afu_add(struct cxl_afu
*afu
)
426 return cxl_add_chardev(afu
, CXL_AFU_MKDEV_M(afu
), &afu
->afu_cdev_m
,
427 &afu
->chardev_m
, "m", "master",
431 int cxl_chardev_s_afu_add(struct cxl_afu
*afu
)
433 return cxl_add_chardev(afu
, CXL_AFU_MKDEV_S(afu
), &afu
->afu_cdev_s
,
434 &afu
->chardev_s
, "s", "shared",
438 void cxl_chardev_afu_remove(struct cxl_afu
*afu
)
440 if (afu
->chardev_d
) {
441 cdev_del(&afu
->afu_cdev_d
);
442 device_unregister(afu
->chardev_d
);
443 afu
->chardev_d
= NULL
;
445 if (afu
->chardev_m
) {
446 cdev_del(&afu
->afu_cdev_m
);
447 device_unregister(afu
->chardev_m
);
448 afu
->chardev_m
= NULL
;
450 if (afu
->chardev_s
) {
451 cdev_del(&afu
->afu_cdev_s
);
452 device_unregister(afu
->chardev_s
);
453 afu
->chardev_s
= NULL
;
457 int cxl_register_afu(struct cxl_afu
*afu
)
459 afu
->dev
.class = cxl_class
;
461 return device_register(&afu
->dev
);
464 int cxl_register_adapter(struct cxl
*adapter
)
466 adapter
->dev
.class = cxl_class
;
469 * Future: When we support dynamically reprogramming the PSL & AFU we
470 * will expose the interface to do that via a chardev:
471 * adapter->dev.devt = CXL_CARD_MKDEV(adapter);
474 return device_register(&adapter
->dev
);
477 int __init
cxl_file_init(void)
482 * If these change we really need to update API. Either change some
483 * flags or update API version number CXL_API_VERSION.
485 BUILD_BUG_ON(CXL_API_VERSION
!= 1);
486 BUILD_BUG_ON(sizeof(struct cxl_ioctl_start_work
) != 64);
487 BUILD_BUG_ON(sizeof(struct cxl_event_header
) != 8);
488 BUILD_BUG_ON(sizeof(struct cxl_event_afu_interrupt
) != 8);
489 BUILD_BUG_ON(sizeof(struct cxl_event_data_storage
) != 32);
490 BUILD_BUG_ON(sizeof(struct cxl_event_afu_error
) != 16);
492 if ((rc
= alloc_chrdev_region(&cxl_dev
, 0, CXL_NUM_MINORS
, "cxl"))) {
493 pr_err("Unable to allocate CXL major number: %i\n", rc
);
497 pr_devel("CXL device allocated, MAJOR %i\n", MAJOR(cxl_dev
));
499 cxl_class
= class_create(THIS_MODULE
, "cxl");
500 if (IS_ERR(cxl_class
)) {
501 pr_err("Unable to create CXL class\n");
502 rc
= PTR_ERR(cxl_class
);
505 cxl_class
->devnode
= cxl_devnode
;
510 unregister_chrdev_region(cxl_dev
, CXL_NUM_MINORS
);
514 void cxl_file_exit(void)
516 unregister_chrdev_region(cxl_dev
, CXL_NUM_MINORS
);
517 class_destroy(cxl_class
);