xref: /openbmc/linux/drivers/dma/ioat/dma.h (revision 6d99a79c)
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  * @completion_pool: DMA buffers for completion ops
66  * @sed_hw_pool: DMA super descriptor pools
67  * @dma_dev: embedded struct dma_device
68  * @version: version of ioatdma device
69  * @msix_entries: irq handlers
70  * @idx: per channel data
71  * @dca: direct cache access context
72  * @irq_mode: interrupt mode (INTX, MSI, MSIX)
73  * @cap: read DMA capabilities register
74  */
75 struct ioatdma_device {
76 	struct pci_dev *pdev;
77 	void __iomem *reg_base;
78 	struct dma_pool *completion_pool;
79 #define MAX_SED_POOLS	5
80 	struct dma_pool *sed_hw_pool[MAX_SED_POOLS];
81 	struct dma_device dma_dev;
82 	u8 version;
83 #define IOAT_MAX_CHANS 4
84 	struct msix_entry msix_entries[IOAT_MAX_CHANS];
85 	struct ioatdma_chan *idx[IOAT_MAX_CHANS];
86 	struct dca_provider *dca;
87 	enum ioat_irq_mode irq_mode;
88 	u32 cap;
89 
90 	/* shadow version for CB3.3 chan reset errata workaround */
91 	u64 msixtba0;
92 	u64 msixdata0;
93 	u32 msixpba;
94 };
95 
96 struct ioat_descs {
97 	void *virt;
98 	dma_addr_t hw;
99 };
100 
101 struct ioatdma_chan {
102 	struct dma_chan dma_chan;
103 	void __iomem *reg_base;
104 	dma_addr_t last_completion;
105 	spinlock_t cleanup_lock;
106 	unsigned long state;
107 	#define IOAT_CHAN_DOWN 0
108 	#define IOAT_COMPLETION_ACK 1
109 	#define IOAT_RESET_PENDING 2
110 	#define IOAT_KOBJ_INIT_FAIL 3
111 	#define IOAT_RUN 5
112 	#define IOAT_CHAN_ACTIVE 6
113 	struct timer_list timer;
114 	#define COMPLETION_TIMEOUT msecs_to_jiffies(100)
115 	#define IDLE_TIMEOUT msecs_to_jiffies(2000)
116 	#define RESET_DELAY msecs_to_jiffies(100)
117 	struct ioatdma_device *ioat_dma;
118 	dma_addr_t completion_dma;
119 	u64 *completion;
120 	struct tasklet_struct cleanup_task;
121 	struct kobject kobj;
122 
123 /* ioat v2 / v3 channel attributes
124  * @xfercap_log; log2 of channel max transfer length (for fast division)
125  * @head: allocated index
126  * @issued: hardware notification point
127  * @tail: cleanup index
128  * @dmacount: identical to 'head' except for occasionally resetting to zero
129  * @alloc_order: log2 of the number of allocated descriptors
130  * @produce: number of descriptors to produce at submit time
131  * @ring: software ring buffer implementation of hardware ring
132  * @prep_lock: serializes descriptor preparation (producers)
133  */
134 	size_t xfercap_log;
135 	u16 head;
136 	u16 issued;
137 	u16 tail;
138 	u16 dmacount;
139 	u16 alloc_order;
140 	u16 produce;
141 	struct ioat_ring_ent **ring;
142 	spinlock_t prep_lock;
143 	struct ioat_descs descs[2];
144 	int desc_chunks;
145 	int intr_coalesce;
146 	int prev_intr_coalesce;
147 };
148 
149 struct ioat_sysfs_entry {
150 	struct attribute attr;
151 	ssize_t (*show)(struct dma_chan *, char *);
152 	ssize_t (*store)(struct dma_chan *, const char *, size_t);
153 };
154 
155 /**
156  * struct ioat_sed_ent - wrapper around super extended hardware descriptor
157  * @hw: hardware SED
158  * @dma: dma address for the SED
159  * @parent: point to the dma descriptor that's the parent
160  * @hw_pool: descriptor pool index
161  */
162 struct ioat_sed_ent {
163 	struct ioat_sed_raw_descriptor *hw;
164 	dma_addr_t dma;
165 	struct ioat_ring_ent *parent;
166 	unsigned int hw_pool;
167 };
168 
169 /**
170  * struct ioat_ring_ent - wrapper around hardware descriptor
171  * @hw: hardware DMA descriptor (for memcpy)
172  * @xor: hardware xor descriptor
173  * @xor_ex: hardware xor extension descriptor
174  * @pq: hardware pq descriptor
175  * @pq_ex: hardware pq extension descriptor
176  * @pqu: hardware pq update descriptor
177  * @raw: hardware raw (un-typed) descriptor
178  * @txd: the generic software descriptor for all engines
179  * @len: total transaction length for unmap
180  * @result: asynchronous result of validate operations
181  * @id: identifier for debug
182  * @sed: pointer to super extended descriptor sw desc
183  */
184 
185 struct ioat_ring_ent {
186 	union {
187 		struct ioat_dma_descriptor *hw;
188 		struct ioat_xor_descriptor *xor;
189 		struct ioat_xor_ext_descriptor *xor_ex;
190 		struct ioat_pq_descriptor *pq;
191 		struct ioat_pq_ext_descriptor *pq_ex;
192 		struct ioat_pq_update_descriptor *pqu;
193 		struct ioat_raw_descriptor *raw;
194 	};
195 	size_t len;
196 	struct dma_async_tx_descriptor txd;
197 	enum sum_check_flags *result;
198 	#ifdef DEBUG
199 	int id;
200 	#endif
201 	struct ioat_sed_ent *sed;
202 };
203 
204 extern const struct sysfs_ops ioat_sysfs_ops;
205 extern struct ioat_sysfs_entry ioat_version_attr;
206 extern struct ioat_sysfs_entry ioat_cap_attr;
207 extern int ioat_pending_level;
208 extern int ioat_ring_alloc_order;
209 extern struct kobj_type ioat_ktype;
210 extern struct kmem_cache *ioat_cache;
211 extern int ioat_ring_max_alloc_order;
212 extern struct kmem_cache *ioat_sed_cache;
213 
214 static inline struct ioatdma_chan *to_ioat_chan(struct dma_chan *c)
215 {
216 	return container_of(c, struct ioatdma_chan, dma_chan);
217 }
218 
219 /* wrapper around hardware descriptor format + additional software fields */
220 #ifdef DEBUG
221 #define set_desc_id(desc, i) ((desc)->id = (i))
222 #define desc_id(desc) ((desc)->id)
223 #else
224 #define set_desc_id(desc, i)
225 #define desc_id(desc) (0)
226 #endif
227 
228 static inline void
229 __dump_desc_dbg(struct ioatdma_chan *ioat_chan, struct ioat_dma_descriptor *hw,
230 		struct dma_async_tx_descriptor *tx, int id)
231 {
232 	struct device *dev = to_dev(ioat_chan);
233 
234 	dev_dbg(dev, "desc[%d]: (%#llx->%#llx) cookie: %d flags: %#x"
235 		" ctl: %#10.8x (op: %#x int_en: %d compl: %d)\n", id,
236 		(unsigned long long) tx->phys,
237 		(unsigned long long) hw->next, tx->cookie, tx->flags,
238 		hw->ctl, hw->ctl_f.op, hw->ctl_f.int_en, hw->ctl_f.compl_write);
239 }
240 
241 #define dump_desc_dbg(c, d) \
242 	({ if (d) __dump_desc_dbg(c, d->hw, &d->txd, desc_id(d)); 0; })
243 
244 static inline struct ioatdma_chan *
245 ioat_chan_by_index(struct ioatdma_device *ioat_dma, int index)
246 {
247 	return ioat_dma->idx[index];
248 }
249 
250 static inline u64 ioat_chansts(struct ioatdma_chan *ioat_chan)
251 {
252 	return readq(ioat_chan->reg_base + IOAT_CHANSTS_OFFSET);
253 }
254 
255 static inline u64 ioat_chansts_to_addr(u64 status)
256 {
257 	return status & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_ADDR;
258 }
259 
260 static inline u32 ioat_chanerr(struct ioatdma_chan *ioat_chan)
261 {
262 	return readl(ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
263 }
264 
265 static inline void ioat_suspend(struct ioatdma_chan *ioat_chan)
266 {
267 	u8 ver = ioat_chan->ioat_dma->version;
268 
269 	writeb(IOAT_CHANCMD_SUSPEND,
270 	       ioat_chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
271 }
272 
273 static inline void ioat_reset(struct ioatdma_chan *ioat_chan)
274 {
275 	u8 ver = ioat_chan->ioat_dma->version;
276 
277 	writeb(IOAT_CHANCMD_RESET,
278 	       ioat_chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
279 }
280 
281 static inline bool ioat_reset_pending(struct ioatdma_chan *ioat_chan)
282 {
283 	u8 ver = ioat_chan->ioat_dma->version;
284 	u8 cmd;
285 
286 	cmd = readb(ioat_chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
287 	return (cmd & IOAT_CHANCMD_RESET) == IOAT_CHANCMD_RESET;
288 }
289 
290 static inline bool is_ioat_active(unsigned long status)
291 {
292 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_ACTIVE);
293 }
294 
295 static inline bool is_ioat_idle(unsigned long status)
296 {
297 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_DONE);
298 }
299 
300 static inline bool is_ioat_halted(unsigned long status)
301 {
302 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_HALTED);
303 }
304 
305 static inline bool is_ioat_suspended(unsigned long status)
306 {
307 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_SUSPENDED);
308 }
309 
310 /* channel was fatally programmed */
311 static inline bool is_ioat_bug(unsigned long err)
312 {
313 	return !!err;
314 }
315 
316 #define IOAT_MAX_ORDER 16
317 #define IOAT_MAX_DESCS 65536
318 #define IOAT_DESCS_PER_2M 32768
319 
320 static inline u32 ioat_ring_size(struct ioatdma_chan *ioat_chan)
321 {
322 	return 1 << ioat_chan->alloc_order;
323 }
324 
325 /* count of descriptors in flight with the engine */
326 static inline u16 ioat_ring_active(struct ioatdma_chan *ioat_chan)
327 {
328 	return CIRC_CNT(ioat_chan->head, ioat_chan->tail,
329 			ioat_ring_size(ioat_chan));
330 }
331 
332 /* count of descriptors pending submission to hardware */
333 static inline u16 ioat_ring_pending(struct ioatdma_chan *ioat_chan)
334 {
335 	return CIRC_CNT(ioat_chan->head, ioat_chan->issued,
336 			ioat_ring_size(ioat_chan));
337 }
338 
339 static inline u32 ioat_ring_space(struct ioatdma_chan *ioat_chan)
340 {
341 	return ioat_ring_size(ioat_chan) - ioat_ring_active(ioat_chan);
342 }
343 
344 static inline u16
345 ioat_xferlen_to_descs(struct ioatdma_chan *ioat_chan, size_t len)
346 {
347 	u16 num_descs = len >> ioat_chan->xfercap_log;
348 
349 	num_descs += !!(len & ((1 << ioat_chan->xfercap_log) - 1));
350 	return num_descs;
351 }
352 
353 static inline struct ioat_ring_ent *
354 ioat_get_ring_ent(struct ioatdma_chan *ioat_chan, u16 idx)
355 {
356 	return ioat_chan->ring[idx & (ioat_ring_size(ioat_chan) - 1)];
357 }
358 
359 static inline void
360 ioat_set_chainaddr(struct ioatdma_chan *ioat_chan, u64 addr)
361 {
362 	writel(addr & 0x00000000FFFFFFFF,
363 	       ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_LOW);
364 	writel(addr >> 32,
365 	       ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_HIGH);
366 }
367 
368 /* IOAT Prep functions */
369 struct dma_async_tx_descriptor *
370 ioat_dma_prep_memcpy_lock(struct dma_chan *c, dma_addr_t dma_dest,
371 			   dma_addr_t dma_src, size_t len, unsigned long flags);
372 struct dma_async_tx_descriptor *
373 ioat_prep_interrupt_lock(struct dma_chan *c, unsigned long flags);
374 struct dma_async_tx_descriptor *
375 ioat_prep_xor(struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src,
376 	       unsigned int src_cnt, size_t len, unsigned long flags);
377 struct dma_async_tx_descriptor *
378 ioat_prep_xor_val(struct dma_chan *chan, dma_addr_t *src,
379 		    unsigned int src_cnt, size_t len,
380 		    enum sum_check_flags *result, unsigned long flags);
381 struct dma_async_tx_descriptor *
382 ioat_prep_pq(struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src,
383 	      unsigned int src_cnt, const unsigned char *scf, size_t len,
384 	      unsigned long flags);
385 struct dma_async_tx_descriptor *
386 ioat_prep_pq_val(struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src,
387 		  unsigned int src_cnt, const unsigned char *scf, size_t len,
388 		  enum sum_check_flags *pqres, unsigned long flags);
389 struct dma_async_tx_descriptor *
390 ioat_prep_pqxor(struct dma_chan *chan, dma_addr_t dst, dma_addr_t *src,
391 		 unsigned int src_cnt, size_t len, unsigned long flags);
392 struct dma_async_tx_descriptor *
393 ioat_prep_pqxor_val(struct dma_chan *chan, dma_addr_t *src,
394 		     unsigned int src_cnt, size_t len,
395 		     enum sum_check_flags *result, unsigned long flags);
396 
397 /* IOAT Operation functions */
398 irqreturn_t ioat_dma_do_interrupt(int irq, void *data);
399 irqreturn_t ioat_dma_do_interrupt_msix(int irq, void *data);
400 struct ioat_ring_ent **
401 ioat_alloc_ring(struct dma_chan *c, int order, gfp_t flags);
402 void ioat_start_null_desc(struct ioatdma_chan *ioat_chan);
403 void ioat_free_ring_ent(struct ioat_ring_ent *desc, struct dma_chan *chan);
404 int ioat_reset_hw(struct ioatdma_chan *ioat_chan);
405 enum dma_status
406 ioat_tx_status(struct dma_chan *c, dma_cookie_t cookie,
407 		struct dma_tx_state *txstate);
408 void ioat_cleanup_event(unsigned long data);
409 void ioat_timer_event(struct timer_list *t);
410 int ioat_check_space_lock(struct ioatdma_chan *ioat_chan, int num_descs);
411 void ioat_issue_pending(struct dma_chan *chan);
412 
413 /* IOAT Init functions */
414 bool is_bwd_ioat(struct pci_dev *pdev);
415 struct dca_provider *ioat_dca_init(struct pci_dev *pdev, void __iomem *iobase);
416 void ioat_kobject_add(struct ioatdma_device *ioat_dma, struct kobj_type *type);
417 void ioat_kobject_del(struct ioatdma_device *ioat_dma);
418 int ioat_dma_setup_interrupts(struct ioatdma_device *ioat_dma);
419 void ioat_stop(struct ioatdma_chan *ioat_chan);
420 #endif /* IOATDMA_H */
421