xref: /openbmc/linux/drivers/dma/ioat/dma.h (revision a8da474e)
1 /*
2  * Copyright(c) 2004 - 2009 Intel Corporation. All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms of the GNU General Public License as published by the Free
6  * Software Foundation; either version 2 of the License, or (at your option)
7  * any later version.
8  *
9  * This program is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  *
14  * The full GNU General Public License is included in this distribution in the
15  * file called COPYING.
16  */
17 #ifndef IOATDMA_H
18 #define IOATDMA_H
19 
20 #include <linux/dmaengine.h>
21 #include <linux/init.h>
22 #include <linux/dmapool.h>
23 #include <linux/cache.h>
24 #include <linux/pci_ids.h>
25 #include <linux/circ_buf.h>
26 #include <linux/interrupt.h>
27 #include "registers.h"
28 #include "hw.h"
29 
30 #define IOAT_DMA_VERSION  "4.00"
31 
32 #define IOAT_DMA_DCA_ANY_CPU		~0
33 
34 #define to_ioatdma_device(dev) container_of(dev, struct ioatdma_device, dma_dev)
35 #define to_dev(ioat_chan) (&(ioat_chan)->ioat_dma->pdev->dev)
36 #define to_pdev(ioat_chan) ((ioat_chan)->ioat_dma->pdev)
37 
38 #define chan_num(ch) ((int)((ch)->reg_base - (ch)->ioat_dma->reg_base) / 0x80)
39 
40 /* ioat hardware assumes at least two sources for raid operations */
41 #define src_cnt_to_sw(x) ((x) + 2)
42 #define src_cnt_to_hw(x) ((x) - 2)
43 #define ndest_to_sw(x) ((x) + 1)
44 #define ndest_to_hw(x) ((x) - 1)
45 #define src16_cnt_to_sw(x) ((x) + 9)
46 #define src16_cnt_to_hw(x) ((x) - 9)
47 
48 /*
49  * workaround for IOAT ver.3.0 null descriptor issue
50  * (channel returns error when size is 0)
51  */
52 #define NULL_DESC_BUFFER_SIZE 1
53 
54 enum ioat_irq_mode {
55 	IOAT_NOIRQ = 0,
56 	IOAT_MSIX,
57 	IOAT_MSI,
58 	IOAT_INTX
59 };
60 
61 /**
62  * struct ioatdma_device - internal representation of a IOAT device
63  * @pdev: PCI-Express device
64  * @reg_base: MMIO register space base address
65  * @dma_pool: for allocating DMA descriptors
66  * @completion_pool: DMA buffers for completion ops
67  * @sed_hw_pool: DMA super descriptor pools
68  * @dma_dev: embedded struct dma_device
69  * @version: version of ioatdma device
70  * @msix_entries: irq handlers
71  * @idx: per channel data
72  * @dca: direct cache access context
73  * @irq_mode: interrupt mode (INTX, MSI, MSIX)
74  * @cap: read DMA capabilities register
75  */
76 struct ioatdma_device {
77 	struct pci_dev *pdev;
78 	void __iomem *reg_base;
79 	struct pci_pool *dma_pool;
80 	struct pci_pool *completion_pool;
81 #define MAX_SED_POOLS	5
82 	struct dma_pool *sed_hw_pool[MAX_SED_POOLS];
83 	struct dma_device dma_dev;
84 	u8 version;
85 #define IOAT_MAX_CHANS 4
86 	struct msix_entry msix_entries[IOAT_MAX_CHANS];
87 	struct ioatdma_chan *idx[IOAT_MAX_CHANS];
88 	struct dca_provider *dca;
89 	enum ioat_irq_mode irq_mode;
90 	u32 cap;
91 };
92 
93 struct ioatdma_chan {
94 	struct dma_chan dma_chan;
95 	void __iomem *reg_base;
96 	dma_addr_t last_completion;
97 	spinlock_t cleanup_lock;
98 	unsigned long state;
99 	#define IOAT_CHAN_DOWN 0
100 	#define IOAT_COMPLETION_ACK 1
101 	#define IOAT_RESET_PENDING 2
102 	#define IOAT_KOBJ_INIT_FAIL 3
103 	#define IOAT_RESHAPE_PENDING 4
104 	#define IOAT_RUN 5
105 	#define IOAT_CHAN_ACTIVE 6
106 	struct timer_list timer;
107 	#define COMPLETION_TIMEOUT msecs_to_jiffies(100)
108 	#define IDLE_TIMEOUT msecs_to_jiffies(2000)
109 	#define RESET_DELAY msecs_to_jiffies(100)
110 	struct ioatdma_device *ioat_dma;
111 	dma_addr_t completion_dma;
112 	u64 *completion;
113 	struct tasklet_struct cleanup_task;
114 	struct kobject kobj;
115 
116 /* ioat v2 / v3 channel attributes
117  * @xfercap_log; log2 of channel max transfer length (for fast division)
118  * @head: allocated index
119  * @issued: hardware notification point
120  * @tail: cleanup index
121  * @dmacount: identical to 'head' except for occasionally resetting to zero
122  * @alloc_order: log2 of the number of allocated descriptors
123  * @produce: number of descriptors to produce at submit time
124  * @ring: software ring buffer implementation of hardware ring
125  * @prep_lock: serializes descriptor preparation (producers)
126  */
127 	size_t xfercap_log;
128 	u16 head;
129 	u16 issued;
130 	u16 tail;
131 	u16 dmacount;
132 	u16 alloc_order;
133 	u16 produce;
134 	struct ioat_ring_ent **ring;
135 	spinlock_t prep_lock;
136 };
137 
138 struct ioat_sysfs_entry {
139 	struct attribute attr;
140 	ssize_t (*show)(struct dma_chan *, char *);
141 };
142 
143 /**
144  * struct ioat_sed_ent - wrapper around super extended hardware descriptor
145  * @hw: hardware SED
146  * @dma: dma address for the SED
147  * @parent: point to the dma descriptor that's the parent
148  * @hw_pool: descriptor pool index
149  */
150 struct ioat_sed_ent {
151 	struct ioat_sed_raw_descriptor *hw;
152 	dma_addr_t dma;
153 	struct ioat_ring_ent *parent;
154 	unsigned int hw_pool;
155 };
156 
157 /**
158  * struct ioat_ring_ent - wrapper around hardware descriptor
159  * @hw: hardware DMA descriptor (for memcpy)
160  * @xor: hardware xor descriptor
161  * @xor_ex: hardware xor extension descriptor
162  * @pq: hardware pq descriptor
163  * @pq_ex: hardware pq extension descriptor
164  * @pqu: hardware pq update descriptor
165  * @raw: hardware raw (un-typed) descriptor
166  * @txd: the generic software descriptor for all engines
167  * @len: total transaction length for unmap
168  * @result: asynchronous result of validate operations
169  * @id: identifier for debug
170  * @sed: pointer to super extended descriptor sw desc
171  */
172 
173 struct ioat_ring_ent {
174 	union {
175 		struct ioat_dma_descriptor *hw;
176 		struct ioat_xor_descriptor *xor;
177 		struct ioat_xor_ext_descriptor *xor_ex;
178 		struct ioat_pq_descriptor *pq;
179 		struct ioat_pq_ext_descriptor *pq_ex;
180 		struct ioat_pq_update_descriptor *pqu;
181 		struct ioat_raw_descriptor *raw;
182 	};
183 	size_t len;
184 	struct dma_async_tx_descriptor txd;
185 	enum sum_check_flags *result;
186 	#ifdef DEBUG
187 	int id;
188 	#endif
189 	struct ioat_sed_ent *sed;
190 };
191 
192 extern const struct sysfs_ops ioat_sysfs_ops;
193 extern struct ioat_sysfs_entry ioat_version_attr;
194 extern struct ioat_sysfs_entry ioat_cap_attr;
195 extern int ioat_pending_level;
196 extern int ioat_ring_alloc_order;
197 extern struct kobj_type ioat_ktype;
198 extern struct kmem_cache *ioat_cache;
199 extern int ioat_ring_max_alloc_order;
200 extern struct kmem_cache *ioat_sed_cache;
201 
202 static inline struct ioatdma_chan *to_ioat_chan(struct dma_chan *c)
203 {
204 	return container_of(c, struct ioatdma_chan, dma_chan);
205 }
206 
207 /* wrapper around hardware descriptor format + additional software fields */
208 #ifdef DEBUG
209 #define set_desc_id(desc, i) ((desc)->id = (i))
210 #define desc_id(desc) ((desc)->id)
211 #else
212 #define set_desc_id(desc, i)
213 #define desc_id(desc) (0)
214 #endif
215 
216 static inline void
217 __dump_desc_dbg(struct ioatdma_chan *ioat_chan, struct ioat_dma_descriptor *hw,
218 		struct dma_async_tx_descriptor *tx, int id)
219 {
220 	struct device *dev = to_dev(ioat_chan);
221 
222 	dev_dbg(dev, "desc[%d]: (%#llx->%#llx) cookie: %d flags: %#x"
223 		" ctl: %#10.8x (op: %#x int_en: %d compl: %d)\n", id,
224 		(unsigned long long) tx->phys,
225 		(unsigned long long) hw->next, tx->cookie, tx->flags,
226 		hw->ctl, hw->ctl_f.op, hw->ctl_f.int_en, hw->ctl_f.compl_write);
227 }
228 
229 #define dump_desc_dbg(c, d) \
230 	({ if (d) __dump_desc_dbg(c, d->hw, &d->txd, desc_id(d)); 0; })
231 
232 static inline struct ioatdma_chan *
233 ioat_chan_by_index(struct ioatdma_device *ioat_dma, int index)
234 {
235 	return ioat_dma->idx[index];
236 }
237 
238 static inline u64 ioat_chansts_32(struct ioatdma_chan *ioat_chan)
239 {
240 	u8 ver = ioat_chan->ioat_dma->version;
241 	u64 status;
242 	u32 status_lo;
243 
244 	/* We need to read the low address first as this causes the
245 	 * chipset to latch the upper bits for the subsequent read
246 	 */
247 	status_lo = readl(ioat_chan->reg_base + IOAT_CHANSTS_OFFSET_LOW(ver));
248 	status = readl(ioat_chan->reg_base + IOAT_CHANSTS_OFFSET_HIGH(ver));
249 	status <<= 32;
250 	status |= status_lo;
251 
252 	return status;
253 }
254 
255 #if BITS_PER_LONG == 64
256 
257 static inline u64 ioat_chansts(struct ioatdma_chan *ioat_chan)
258 {
259 	u8 ver = ioat_chan->ioat_dma->version;
260 	u64 status;
261 
262 	 /* With IOAT v3.3 the status register is 64bit.  */
263 	if (ver >= IOAT_VER_3_3)
264 		status = readq(ioat_chan->reg_base + IOAT_CHANSTS_OFFSET(ver));
265 	else
266 		status = ioat_chansts_32(ioat_chan);
267 
268 	return status;
269 }
270 
271 #else
272 #define ioat_chansts ioat_chansts_32
273 #endif
274 
275 static inline u64 ioat_chansts_to_addr(u64 status)
276 {
277 	return status & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_ADDR;
278 }
279 
280 static inline u32 ioat_chanerr(struct ioatdma_chan *ioat_chan)
281 {
282 	return readl(ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
283 }
284 
285 static inline void ioat_suspend(struct ioatdma_chan *ioat_chan)
286 {
287 	u8 ver = ioat_chan->ioat_dma->version;
288 
289 	writeb(IOAT_CHANCMD_SUSPEND,
290 	       ioat_chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
291 }
292 
293 static inline void ioat_reset(struct ioatdma_chan *ioat_chan)
294 {
295 	u8 ver = ioat_chan->ioat_dma->version;
296 
297 	writeb(IOAT_CHANCMD_RESET,
298 	       ioat_chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
299 }
300 
301 static inline bool ioat_reset_pending(struct ioatdma_chan *ioat_chan)
302 {
303 	u8 ver = ioat_chan->ioat_dma->version;
304 	u8 cmd;
305 
306 	cmd = readb(ioat_chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
307 	return (cmd & IOAT_CHANCMD_RESET) == IOAT_CHANCMD_RESET;
308 }
309 
310 static inline bool is_ioat_active(unsigned long status)
311 {
312 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_ACTIVE);
313 }
314 
315 static inline bool is_ioat_idle(unsigned long status)
316 {
317 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_DONE);
318 }
319 
320 static inline bool is_ioat_halted(unsigned long status)
321 {
322 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_HALTED);
323 }
324 
325 static inline bool is_ioat_suspended(unsigned long status)
326 {
327 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_SUSPENDED);
328 }
329 
330 /* channel was fatally programmed */
331 static inline bool is_ioat_bug(unsigned long err)
332 {
333 	return !!err;
334 }
335 
336 #define IOAT_MAX_ORDER 16
337 #define ioat_get_alloc_order() \
338 	(min(ioat_ring_alloc_order, IOAT_MAX_ORDER))
339 #define ioat_get_max_alloc_order() \
340 	(min(ioat_ring_max_alloc_order, IOAT_MAX_ORDER))
341 
342 static inline u32 ioat_ring_size(struct ioatdma_chan *ioat_chan)
343 {
344 	return 1 << ioat_chan->alloc_order;
345 }
346 
347 /* count of descriptors in flight with the engine */
348 static inline u16 ioat_ring_active(struct ioatdma_chan *ioat_chan)
349 {
350 	return CIRC_CNT(ioat_chan->head, ioat_chan->tail,
351 			ioat_ring_size(ioat_chan));
352 }
353 
354 /* count of descriptors pending submission to hardware */
355 static inline u16 ioat_ring_pending(struct ioatdma_chan *ioat_chan)
356 {
357 	return CIRC_CNT(ioat_chan->head, ioat_chan->issued,
358 			ioat_ring_size(ioat_chan));
359 }
360 
361 static inline u32 ioat_ring_space(struct ioatdma_chan *ioat_chan)
362 {
363 	return ioat_ring_size(ioat_chan) - ioat_ring_active(ioat_chan);
364 }
365 
366 static inline u16
367 ioat_xferlen_to_descs(struct ioatdma_chan *ioat_chan, size_t len)
368 {
369 	u16 num_descs = len >> ioat_chan->xfercap_log;
370 
371 	num_descs += !!(len & ((1 << ioat_chan->xfercap_log) - 1));
372 	return num_descs;
373 }
374 
375 static inline struct ioat_ring_ent *
376 ioat_get_ring_ent(struct ioatdma_chan *ioat_chan, u16 idx)
377 {
378 	return ioat_chan->ring[idx & (ioat_ring_size(ioat_chan) - 1)];
379 }
380 
381 static inline void
382 ioat_set_chainaddr(struct ioatdma_chan *ioat_chan, u64 addr)
383 {
384 	writel(addr & 0x00000000FFFFFFFF,
385 	       ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_LOW);
386 	writel(addr >> 32,
387 	       ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_HIGH);
388 }
389 
390 /* IOAT Prep functions */
391 struct dma_async_tx_descriptor *
392 ioat_dma_prep_memcpy_lock(struct dma_chan *c, dma_addr_t dma_dest,
393 			   dma_addr_t dma_src, size_t len, unsigned long flags);
394 struct dma_async_tx_descriptor *
395 ioat_prep_interrupt_lock(struct dma_chan *c, unsigned long flags);
396 struct dma_async_tx_descriptor *
397 ioat_prep_xor(struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src,
398 	       unsigned int src_cnt, size_t len, unsigned long flags);
399 struct dma_async_tx_descriptor *
400 ioat_prep_xor_val(struct dma_chan *chan, dma_addr_t *src,
401 		    unsigned int src_cnt, size_t len,
402 		    enum sum_check_flags *result, unsigned long flags);
403 struct dma_async_tx_descriptor *
404 ioat_prep_pq(struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src,
405 	      unsigned int src_cnt, const unsigned char *scf, size_t len,
406 	      unsigned long flags);
407 struct dma_async_tx_descriptor *
408 ioat_prep_pq_val(struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src,
409 		  unsigned int src_cnt, const unsigned char *scf, size_t len,
410 		  enum sum_check_flags *pqres, unsigned long flags);
411 struct dma_async_tx_descriptor *
412 ioat_prep_pqxor(struct dma_chan *chan, dma_addr_t dst, dma_addr_t *src,
413 		 unsigned int src_cnt, size_t len, unsigned long flags);
414 struct dma_async_tx_descriptor *
415 ioat_prep_pqxor_val(struct dma_chan *chan, dma_addr_t *src,
416 		     unsigned int src_cnt, size_t len,
417 		     enum sum_check_flags *result, unsigned long flags);
418 
419 /* IOAT Operation functions */
420 irqreturn_t ioat_dma_do_interrupt(int irq, void *data);
421 irqreturn_t ioat_dma_do_interrupt_msix(int irq, void *data);
422 struct ioat_ring_ent **
423 ioat_alloc_ring(struct dma_chan *c, int order, gfp_t flags);
424 void ioat_start_null_desc(struct ioatdma_chan *ioat_chan);
425 void ioat_free_ring_ent(struct ioat_ring_ent *desc, struct dma_chan *chan);
426 int ioat_reset_hw(struct ioatdma_chan *ioat_chan);
427 enum dma_status
428 ioat_tx_status(struct dma_chan *c, dma_cookie_t cookie,
429 		struct dma_tx_state *txstate);
430 void ioat_cleanup_event(unsigned long data);
431 void ioat_timer_event(unsigned long data);
432 int ioat_check_space_lock(struct ioatdma_chan *ioat_chan, int num_descs);
433 void ioat_issue_pending(struct dma_chan *chan);
434 void ioat_timer_event(unsigned long data);
435 
436 /* IOAT Init functions */
437 bool is_bwd_ioat(struct pci_dev *pdev);
438 struct dca_provider *ioat_dca_init(struct pci_dev *pdev, void __iomem *iobase);
439 void ioat_kobject_add(struct ioatdma_device *ioat_dma, struct kobj_type *type);
440 void ioat_kobject_del(struct ioatdma_device *ioat_dma);
441 int ioat_dma_setup_interrupts(struct ioatdma_device *ioat_dma);
442 void ioat_stop(struct ioatdma_chan *ioat_chan);
443 #endif /* IOATDMA_H */
444