xref: /openbmc/linux/drivers/dma/ioat/dma.h (revision a2cce7a9)
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 	struct msix_entry msix_entries[4];
86 	struct ioatdma_chan *idx[4];
87 	struct dca_provider *dca;
88 	enum ioat_irq_mode irq_mode;
89 	u32 cap;
90 };
91 
92 struct ioatdma_chan {
93 	struct dma_chan dma_chan;
94 	void __iomem *reg_base;
95 	dma_addr_t last_completion;
96 	spinlock_t cleanup_lock;
97 	unsigned long state;
98 	#define IOAT_COMPLETION_ACK 1
99 	#define IOAT_RESET_PENDING 2
100 	#define IOAT_KOBJ_INIT_FAIL 3
101 	#define IOAT_RESHAPE_PENDING 4
102 	#define IOAT_RUN 5
103 	#define IOAT_CHAN_ACTIVE 6
104 	struct timer_list timer;
105 	#define COMPLETION_TIMEOUT msecs_to_jiffies(100)
106 	#define IDLE_TIMEOUT msecs_to_jiffies(2000)
107 	#define RESET_DELAY msecs_to_jiffies(100)
108 	struct ioatdma_device *ioat_dma;
109 	dma_addr_t completion_dma;
110 	u64 *completion;
111 	struct tasklet_struct cleanup_task;
112 	struct kobject kobj;
113 
114 /* ioat v2 / v3 channel attributes
115  * @xfercap_log; log2 of channel max transfer length (for fast division)
116  * @head: allocated index
117  * @issued: hardware notification point
118  * @tail: cleanup index
119  * @dmacount: identical to 'head' except for occasionally resetting to zero
120  * @alloc_order: log2 of the number of allocated descriptors
121  * @produce: number of descriptors to produce at submit time
122  * @ring: software ring buffer implementation of hardware ring
123  * @prep_lock: serializes descriptor preparation (producers)
124  */
125 	size_t xfercap_log;
126 	u16 head;
127 	u16 issued;
128 	u16 tail;
129 	u16 dmacount;
130 	u16 alloc_order;
131 	u16 produce;
132 	struct ioat_ring_ent **ring;
133 	spinlock_t prep_lock;
134 };
135 
136 struct ioat_sysfs_entry {
137 	struct attribute attr;
138 	ssize_t (*show)(struct dma_chan *, char *);
139 };
140 
141 /**
142  * struct ioat_sed_ent - wrapper around super extended hardware descriptor
143  * @hw: hardware SED
144  * @dma: dma address for the SED
145  * @parent: point to the dma descriptor that's the parent
146  * @hw_pool: descriptor pool index
147  */
148 struct ioat_sed_ent {
149 	struct ioat_sed_raw_descriptor *hw;
150 	dma_addr_t dma;
151 	struct ioat_ring_ent *parent;
152 	unsigned int hw_pool;
153 };
154 
155 /**
156  * struct ioat_ring_ent - wrapper around hardware descriptor
157  * @hw: hardware DMA descriptor (for memcpy)
158  * @xor: hardware xor descriptor
159  * @xor_ex: hardware xor extension descriptor
160  * @pq: hardware pq descriptor
161  * @pq_ex: hardware pq extension descriptor
162  * @pqu: hardware pq update descriptor
163  * @raw: hardware raw (un-typed) descriptor
164  * @txd: the generic software descriptor for all engines
165  * @len: total transaction length for unmap
166  * @result: asynchronous result of validate operations
167  * @id: identifier for debug
168  * @sed: pointer to super extended descriptor sw desc
169  */
170 
171 struct ioat_ring_ent {
172 	union {
173 		struct ioat_dma_descriptor *hw;
174 		struct ioat_xor_descriptor *xor;
175 		struct ioat_xor_ext_descriptor *xor_ex;
176 		struct ioat_pq_descriptor *pq;
177 		struct ioat_pq_ext_descriptor *pq_ex;
178 		struct ioat_pq_update_descriptor *pqu;
179 		struct ioat_raw_descriptor *raw;
180 	};
181 	size_t len;
182 	struct dma_async_tx_descriptor txd;
183 	enum sum_check_flags *result;
184 	#ifdef DEBUG
185 	int id;
186 	#endif
187 	struct ioat_sed_ent *sed;
188 };
189 
190 extern const struct sysfs_ops ioat_sysfs_ops;
191 extern struct ioat_sysfs_entry ioat_version_attr;
192 extern struct ioat_sysfs_entry ioat_cap_attr;
193 extern int ioat_pending_level;
194 extern int ioat_ring_alloc_order;
195 extern struct kobj_type ioat_ktype;
196 extern struct kmem_cache *ioat_cache;
197 extern int ioat_ring_max_alloc_order;
198 extern struct kmem_cache *ioat_sed_cache;
199 
200 static inline struct ioatdma_chan *to_ioat_chan(struct dma_chan *c)
201 {
202 	return container_of(c, struct ioatdma_chan, dma_chan);
203 }
204 
205 /* wrapper around hardware descriptor format + additional software fields */
206 #ifdef DEBUG
207 #define set_desc_id(desc, i) ((desc)->id = (i))
208 #define desc_id(desc) ((desc)->id)
209 #else
210 #define set_desc_id(desc, i)
211 #define desc_id(desc) (0)
212 #endif
213 
214 static inline void
215 __dump_desc_dbg(struct ioatdma_chan *ioat_chan, struct ioat_dma_descriptor *hw,
216 		struct dma_async_tx_descriptor *tx, int id)
217 {
218 	struct device *dev = to_dev(ioat_chan);
219 
220 	dev_dbg(dev, "desc[%d]: (%#llx->%#llx) cookie: %d flags: %#x"
221 		" ctl: %#10.8x (op: %#x int_en: %d compl: %d)\n", id,
222 		(unsigned long long) tx->phys,
223 		(unsigned long long) hw->next, tx->cookie, tx->flags,
224 		hw->ctl, hw->ctl_f.op, hw->ctl_f.int_en, hw->ctl_f.compl_write);
225 }
226 
227 #define dump_desc_dbg(c, d) \
228 	({ if (d) __dump_desc_dbg(c, d->hw, &d->txd, desc_id(d)); 0; })
229 
230 static inline struct ioatdma_chan *
231 ioat_chan_by_index(struct ioatdma_device *ioat_dma, int index)
232 {
233 	return ioat_dma->idx[index];
234 }
235 
236 static inline u64 ioat_chansts_32(struct ioatdma_chan *ioat_chan)
237 {
238 	u8 ver = ioat_chan->ioat_dma->version;
239 	u64 status;
240 	u32 status_lo;
241 
242 	/* We need to read the low address first as this causes the
243 	 * chipset to latch the upper bits for the subsequent read
244 	 */
245 	status_lo = readl(ioat_chan->reg_base + IOAT_CHANSTS_OFFSET_LOW(ver));
246 	status = readl(ioat_chan->reg_base + IOAT_CHANSTS_OFFSET_HIGH(ver));
247 	status <<= 32;
248 	status |= status_lo;
249 
250 	return status;
251 }
252 
253 #if BITS_PER_LONG == 64
254 
255 static inline u64 ioat_chansts(struct ioatdma_chan *ioat_chan)
256 {
257 	u8 ver = ioat_chan->ioat_dma->version;
258 	u64 status;
259 
260 	 /* With IOAT v3.3 the status register is 64bit.  */
261 	if (ver >= IOAT_VER_3_3)
262 		status = readq(ioat_chan->reg_base + IOAT_CHANSTS_OFFSET(ver));
263 	else
264 		status = ioat_chansts_32(ioat_chan);
265 
266 	return status;
267 }
268 
269 #else
270 #define ioat_chansts ioat_chansts_32
271 #endif
272 
273 static inline u64 ioat_chansts_to_addr(u64 status)
274 {
275 	return status & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_ADDR;
276 }
277 
278 static inline u32 ioat_chanerr(struct ioatdma_chan *ioat_chan)
279 {
280 	return readl(ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
281 }
282 
283 static inline void ioat_suspend(struct ioatdma_chan *ioat_chan)
284 {
285 	u8 ver = ioat_chan->ioat_dma->version;
286 
287 	writeb(IOAT_CHANCMD_SUSPEND,
288 	       ioat_chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
289 }
290 
291 static inline void ioat_reset(struct ioatdma_chan *ioat_chan)
292 {
293 	u8 ver = ioat_chan->ioat_dma->version;
294 
295 	writeb(IOAT_CHANCMD_RESET,
296 	       ioat_chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
297 }
298 
299 static inline bool ioat_reset_pending(struct ioatdma_chan *ioat_chan)
300 {
301 	u8 ver = ioat_chan->ioat_dma->version;
302 	u8 cmd;
303 
304 	cmd = readb(ioat_chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
305 	return (cmd & IOAT_CHANCMD_RESET) == IOAT_CHANCMD_RESET;
306 }
307 
308 static inline bool is_ioat_active(unsigned long status)
309 {
310 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_ACTIVE);
311 }
312 
313 static inline bool is_ioat_idle(unsigned long status)
314 {
315 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_DONE);
316 }
317 
318 static inline bool is_ioat_halted(unsigned long status)
319 {
320 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_HALTED);
321 }
322 
323 static inline bool is_ioat_suspended(unsigned long status)
324 {
325 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_SUSPENDED);
326 }
327 
328 /* channel was fatally programmed */
329 static inline bool is_ioat_bug(unsigned long err)
330 {
331 	return !!err;
332 }
333 
334 #define IOAT_MAX_ORDER 16
335 #define ioat_get_alloc_order() \
336 	(min(ioat_ring_alloc_order, IOAT_MAX_ORDER))
337 #define ioat_get_max_alloc_order() \
338 	(min(ioat_ring_max_alloc_order, IOAT_MAX_ORDER))
339 
340 static inline u32 ioat_ring_size(struct ioatdma_chan *ioat_chan)
341 {
342 	return 1 << ioat_chan->alloc_order;
343 }
344 
345 /* count of descriptors in flight with the engine */
346 static inline u16 ioat_ring_active(struct ioatdma_chan *ioat_chan)
347 {
348 	return CIRC_CNT(ioat_chan->head, ioat_chan->tail,
349 			ioat_ring_size(ioat_chan));
350 }
351 
352 /* count of descriptors pending submission to hardware */
353 static inline u16 ioat_ring_pending(struct ioatdma_chan *ioat_chan)
354 {
355 	return CIRC_CNT(ioat_chan->head, ioat_chan->issued,
356 			ioat_ring_size(ioat_chan));
357 }
358 
359 static inline u32 ioat_ring_space(struct ioatdma_chan *ioat_chan)
360 {
361 	return ioat_ring_size(ioat_chan) - ioat_ring_active(ioat_chan);
362 }
363 
364 static inline u16
365 ioat_xferlen_to_descs(struct ioatdma_chan *ioat_chan, size_t len)
366 {
367 	u16 num_descs = len >> ioat_chan->xfercap_log;
368 
369 	num_descs += !!(len & ((1 << ioat_chan->xfercap_log) - 1));
370 	return num_descs;
371 }
372 
373 static inline struct ioat_ring_ent *
374 ioat_get_ring_ent(struct ioatdma_chan *ioat_chan, u16 idx)
375 {
376 	return ioat_chan->ring[idx & (ioat_ring_size(ioat_chan) - 1)];
377 }
378 
379 static inline void
380 ioat_set_chainaddr(struct ioatdma_chan *ioat_chan, u64 addr)
381 {
382 	writel(addr & 0x00000000FFFFFFFF,
383 	       ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_LOW);
384 	writel(addr >> 32,
385 	       ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_HIGH);
386 }
387 
388 /* IOAT Prep functions */
389 struct dma_async_tx_descriptor *
390 ioat_dma_prep_memcpy_lock(struct dma_chan *c, dma_addr_t dma_dest,
391 			   dma_addr_t dma_src, size_t len, unsigned long flags);
392 struct dma_async_tx_descriptor *
393 ioat_prep_interrupt_lock(struct dma_chan *c, unsigned long flags);
394 struct dma_async_tx_descriptor *
395 ioat_prep_xor(struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src,
396 	       unsigned int src_cnt, size_t len, unsigned long flags);
397 struct dma_async_tx_descriptor *
398 ioat_prep_xor_val(struct dma_chan *chan, dma_addr_t *src,
399 		    unsigned int src_cnt, size_t len,
400 		    enum sum_check_flags *result, unsigned long flags);
401 struct dma_async_tx_descriptor *
402 ioat_prep_pq(struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src,
403 	      unsigned int src_cnt, const unsigned char *scf, size_t len,
404 	      unsigned long flags);
405 struct dma_async_tx_descriptor *
406 ioat_prep_pq_val(struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src,
407 		  unsigned int src_cnt, const unsigned char *scf, size_t len,
408 		  enum sum_check_flags *pqres, unsigned long flags);
409 struct dma_async_tx_descriptor *
410 ioat_prep_pqxor(struct dma_chan *chan, dma_addr_t dst, dma_addr_t *src,
411 		 unsigned int src_cnt, size_t len, unsigned long flags);
412 struct dma_async_tx_descriptor *
413 ioat_prep_pqxor_val(struct dma_chan *chan, dma_addr_t *src,
414 		     unsigned int src_cnt, size_t len,
415 		     enum sum_check_flags *result, unsigned long flags);
416 
417 /* IOAT Operation functions */
418 irqreturn_t ioat_dma_do_interrupt(int irq, void *data);
419 irqreturn_t ioat_dma_do_interrupt_msix(int irq, void *data);
420 struct ioat_ring_ent **
421 ioat_alloc_ring(struct dma_chan *c, int order, gfp_t flags);
422 void ioat_start_null_desc(struct ioatdma_chan *ioat_chan);
423 void ioat_free_ring_ent(struct ioat_ring_ent *desc, struct dma_chan *chan);
424 int ioat_reset_hw(struct ioatdma_chan *ioat_chan);
425 enum dma_status
426 ioat_tx_status(struct dma_chan *c, dma_cookie_t cookie,
427 		struct dma_tx_state *txstate);
428 void ioat_cleanup_event(unsigned long data);
429 void ioat_timer_event(unsigned long data);
430 int ioat_check_space_lock(struct ioatdma_chan *ioat_chan, int num_descs);
431 void ioat_issue_pending(struct dma_chan *chan);
432 void ioat_timer_event(unsigned long data);
433 
434 /* IOAT Init functions */
435 bool is_bwd_ioat(struct pci_dev *pdev);
436 struct dca_provider *ioat_dca_init(struct pci_dev *pdev, void __iomem *iobase);
437 void ioat_kobject_add(struct ioatdma_device *ioat_dma, struct kobj_type *type);
438 void ioat_kobject_del(struct ioatdma_device *ioat_dma);
439 int ioat_dma_setup_interrupts(struct ioatdma_device *ioat_dma);
440 void ioat_stop(struct ioatdma_chan *ioat_chan);
441 #endif /* IOATDMA_H */
442