xref: /openbmc/linux/drivers/dma/ioat/dma.h (revision 55fd7e02)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * Copyright(c) 2004 - 2009 Intel Corporation. All rights reserved.
4  */
5 #ifndef IOATDMA_H
6 #define IOATDMA_H
7 
8 #include <linux/dmaengine.h>
9 #include <linux/init.h>
10 #include <linux/dmapool.h>
11 #include <linux/cache.h>
12 #include <linux/pci_ids.h>
13 #include <linux/circ_buf.h>
14 #include <linux/interrupt.h>
15 #include "registers.h"
16 #include "hw.h"
17 
18 #define IOAT_DMA_VERSION  "5.00"
19 
20 #define IOAT_DMA_DCA_ANY_CPU		~0
21 
22 #define to_ioatdma_device(dev) container_of(dev, struct ioatdma_device, dma_dev)
23 #define to_dev(ioat_chan) (&(ioat_chan)->ioat_dma->pdev->dev)
24 #define to_pdev(ioat_chan) ((ioat_chan)->ioat_dma->pdev)
25 
26 #define chan_num(ch) ((int)((ch)->reg_base - (ch)->ioat_dma->reg_base) / 0x80)
27 
28 /* ioat hardware assumes at least two sources for raid operations */
29 #define src_cnt_to_sw(x) ((x) + 2)
30 #define src_cnt_to_hw(x) ((x) - 2)
31 #define ndest_to_sw(x) ((x) + 1)
32 #define ndest_to_hw(x) ((x) - 1)
33 #define src16_cnt_to_sw(x) ((x) + 9)
34 #define src16_cnt_to_hw(x) ((x) - 9)
35 
36 /*
37  * workaround for IOAT ver.3.0 null descriptor issue
38  * (channel returns error when size is 0)
39  */
40 #define NULL_DESC_BUFFER_SIZE 1
41 
42 enum ioat_irq_mode {
43 	IOAT_NOIRQ = 0,
44 	IOAT_MSIX,
45 	IOAT_MSI,
46 	IOAT_INTX
47 };
48 
49 /**
50  * struct ioatdma_device - internal representation of a IOAT device
51  * @pdev: PCI-Express device
52  * @reg_base: MMIO register space base address
53  * @completion_pool: DMA buffers for completion ops
54  * @sed_hw_pool: DMA super descriptor pools
55  * @dma_dev: embedded struct dma_device
56  * @version: version of ioatdma device
57  * @msix_entries: irq handlers
58  * @idx: per channel data
59  * @dca: direct cache access context
60  * @irq_mode: interrupt mode (INTX, MSI, MSIX)
61  * @cap: read DMA capabilities register
62  */
63 struct ioatdma_device {
64 	struct pci_dev *pdev;
65 	void __iomem *reg_base;
66 	struct dma_pool *completion_pool;
67 #define MAX_SED_POOLS	5
68 	struct dma_pool *sed_hw_pool[MAX_SED_POOLS];
69 	struct dma_device dma_dev;
70 	u8 version;
71 #define IOAT_MAX_CHANS 4
72 	struct msix_entry msix_entries[IOAT_MAX_CHANS];
73 	struct ioatdma_chan *idx[IOAT_MAX_CHANS];
74 	struct dca_provider *dca;
75 	enum ioat_irq_mode irq_mode;
76 	u32 cap;
77 
78 	/* shadow version for CB3.3 chan reset errata workaround */
79 	u64 msixtba0;
80 	u64 msixdata0;
81 	u32 msixpba;
82 };
83 
84 #define IOAT_MAX_ORDER 16
85 #define IOAT_MAX_DESCS (1 << IOAT_MAX_ORDER)
86 #define IOAT_CHUNK_SIZE (SZ_512K)
87 #define IOAT_DESCS_PER_CHUNK (IOAT_CHUNK_SIZE / IOAT_DESC_SZ)
88 
89 struct ioat_descs {
90 	void *virt;
91 	dma_addr_t hw;
92 };
93 
94 struct ioatdma_chan {
95 	struct dma_chan dma_chan;
96 	void __iomem *reg_base;
97 	dma_addr_t last_completion;
98 	spinlock_t cleanup_lock;
99 	unsigned long state;
100 	#define IOAT_CHAN_DOWN 0
101 	#define IOAT_COMPLETION_ACK 1
102 	#define IOAT_RESET_PENDING 2
103 	#define IOAT_KOBJ_INIT_FAIL 3
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 	struct ioat_descs descs[IOAT_MAX_DESCS / IOAT_DESCS_PER_CHUNK];
137 	int desc_chunks;
138 	int intr_coalesce;
139 	int prev_intr_coalesce;
140 };
141 
142 struct ioat_sysfs_entry {
143 	struct attribute attr;
144 	ssize_t (*show)(struct dma_chan *, char *);
145 	ssize_t (*store)(struct dma_chan *, const char *, size_t);
146 };
147 
148 /**
149  * struct ioat_sed_ent - wrapper around super extended hardware descriptor
150  * @hw: hardware SED
151  * @dma: dma address for the SED
152  * @parent: point to the dma descriptor that's the parent
153  * @hw_pool: descriptor pool index
154  */
155 struct ioat_sed_ent {
156 	struct ioat_sed_raw_descriptor *hw;
157 	dma_addr_t dma;
158 	struct ioat_ring_ent *parent;
159 	unsigned int hw_pool;
160 };
161 
162 /**
163  * struct ioat_ring_ent - wrapper around hardware descriptor
164  * @hw: hardware DMA descriptor (for memcpy)
165  * @xor: hardware xor descriptor
166  * @xor_ex: hardware xor extension descriptor
167  * @pq: hardware pq descriptor
168  * @pq_ex: hardware pq extension descriptor
169  * @pqu: hardware pq update descriptor
170  * @raw: hardware raw (un-typed) descriptor
171  * @txd: the generic software descriptor for all engines
172  * @len: total transaction length for unmap
173  * @result: asynchronous result of validate operations
174  * @id: identifier for debug
175  * @sed: pointer to super extended descriptor sw desc
176  */
177 
178 struct ioat_ring_ent {
179 	union {
180 		struct ioat_dma_descriptor *hw;
181 		struct ioat_xor_descriptor *xor;
182 		struct ioat_xor_ext_descriptor *xor_ex;
183 		struct ioat_pq_descriptor *pq;
184 		struct ioat_pq_ext_descriptor *pq_ex;
185 		struct ioat_pq_update_descriptor *pqu;
186 		struct ioat_raw_descriptor *raw;
187 	};
188 	size_t len;
189 	struct dma_async_tx_descriptor txd;
190 	enum sum_check_flags *result;
191 	#ifdef DEBUG
192 	int id;
193 	#endif
194 	struct ioat_sed_ent *sed;
195 };
196 
197 extern const struct sysfs_ops ioat_sysfs_ops;
198 extern struct ioat_sysfs_entry ioat_version_attr;
199 extern struct ioat_sysfs_entry ioat_cap_attr;
200 extern int ioat_pending_level;
201 extern int ioat_ring_alloc_order;
202 extern struct kobj_type ioat_ktype;
203 extern struct kmem_cache *ioat_cache;
204 extern int ioat_ring_max_alloc_order;
205 extern struct kmem_cache *ioat_sed_cache;
206 
207 static inline struct ioatdma_chan *to_ioat_chan(struct dma_chan *c)
208 {
209 	return container_of(c, struct ioatdma_chan, dma_chan);
210 }
211 
212 /* wrapper around hardware descriptor format + additional software fields */
213 #ifdef DEBUG
214 #define set_desc_id(desc, i) ((desc)->id = (i))
215 #define desc_id(desc) ((desc)->id)
216 #else
217 #define set_desc_id(desc, i)
218 #define desc_id(desc) (0)
219 #endif
220 
221 static inline void
222 __dump_desc_dbg(struct ioatdma_chan *ioat_chan, struct ioat_dma_descriptor *hw,
223 		struct dma_async_tx_descriptor *tx, int id)
224 {
225 	struct device *dev = to_dev(ioat_chan);
226 
227 	dev_dbg(dev, "desc[%d]: (%#llx->%#llx) cookie: %d flags: %#x"
228 		" ctl: %#10.8x (op: %#x int_en: %d compl: %d)\n", id,
229 		(unsigned long long) tx->phys,
230 		(unsigned long long) hw->next, tx->cookie, tx->flags,
231 		hw->ctl, hw->ctl_f.op, hw->ctl_f.int_en, hw->ctl_f.compl_write);
232 }
233 
234 #define dump_desc_dbg(c, d) \
235 	({ if (d) __dump_desc_dbg(c, d->hw, &d->txd, desc_id(d)); 0; })
236 
237 static inline struct ioatdma_chan *
238 ioat_chan_by_index(struct ioatdma_device *ioat_dma, int index)
239 {
240 	return ioat_dma->idx[index];
241 }
242 
243 static inline u64 ioat_chansts(struct ioatdma_chan *ioat_chan)
244 {
245 	return readq(ioat_chan->reg_base + IOAT_CHANSTS_OFFSET);
246 }
247 
248 static inline u64 ioat_chansts_to_addr(u64 status)
249 {
250 	return status & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_ADDR;
251 }
252 
253 static inline u32 ioat_chanerr(struct ioatdma_chan *ioat_chan)
254 {
255 	return readl(ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
256 }
257 
258 static inline void ioat_suspend(struct ioatdma_chan *ioat_chan)
259 {
260 	u8 ver = ioat_chan->ioat_dma->version;
261 
262 	writeb(IOAT_CHANCMD_SUSPEND,
263 	       ioat_chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
264 }
265 
266 static inline void ioat_reset(struct ioatdma_chan *ioat_chan)
267 {
268 	u8 ver = ioat_chan->ioat_dma->version;
269 
270 	writeb(IOAT_CHANCMD_RESET,
271 	       ioat_chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
272 }
273 
274 static inline bool ioat_reset_pending(struct ioatdma_chan *ioat_chan)
275 {
276 	u8 ver = ioat_chan->ioat_dma->version;
277 	u8 cmd;
278 
279 	cmd = readb(ioat_chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
280 	return (cmd & IOAT_CHANCMD_RESET) == IOAT_CHANCMD_RESET;
281 }
282 
283 static inline bool is_ioat_active(unsigned long status)
284 {
285 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_ACTIVE);
286 }
287 
288 static inline bool is_ioat_idle(unsigned long status)
289 {
290 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_DONE);
291 }
292 
293 static inline bool is_ioat_halted(unsigned long status)
294 {
295 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_HALTED);
296 }
297 
298 static inline bool is_ioat_suspended(unsigned long status)
299 {
300 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_SUSPENDED);
301 }
302 
303 /* channel was fatally programmed */
304 static inline bool is_ioat_bug(unsigned long err)
305 {
306 	return !!err;
307 }
308 
309 
310 static inline u32 ioat_ring_size(struct ioatdma_chan *ioat_chan)
311 {
312 	return 1 << ioat_chan->alloc_order;
313 }
314 
315 /* count of descriptors in flight with the engine */
316 static inline u16 ioat_ring_active(struct ioatdma_chan *ioat_chan)
317 {
318 	return CIRC_CNT(ioat_chan->head, ioat_chan->tail,
319 			ioat_ring_size(ioat_chan));
320 }
321 
322 /* count of descriptors pending submission to hardware */
323 static inline u16 ioat_ring_pending(struct ioatdma_chan *ioat_chan)
324 {
325 	return CIRC_CNT(ioat_chan->head, ioat_chan->issued,
326 			ioat_ring_size(ioat_chan));
327 }
328 
329 static inline u32 ioat_ring_space(struct ioatdma_chan *ioat_chan)
330 {
331 	return ioat_ring_size(ioat_chan) - ioat_ring_active(ioat_chan);
332 }
333 
334 static inline u16
335 ioat_xferlen_to_descs(struct ioatdma_chan *ioat_chan, size_t len)
336 {
337 	u16 num_descs = len >> ioat_chan->xfercap_log;
338 
339 	num_descs += !!(len & ((1 << ioat_chan->xfercap_log) - 1));
340 	return num_descs;
341 }
342 
343 static inline struct ioat_ring_ent *
344 ioat_get_ring_ent(struct ioatdma_chan *ioat_chan, u16 idx)
345 {
346 	return ioat_chan->ring[idx & (ioat_ring_size(ioat_chan) - 1)];
347 }
348 
349 static inline void
350 ioat_set_chainaddr(struct ioatdma_chan *ioat_chan, u64 addr)
351 {
352 	writel(addr & 0x00000000FFFFFFFF,
353 	       ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_LOW);
354 	writel(addr >> 32,
355 	       ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_HIGH);
356 }
357 
358 /* IOAT Prep functions */
359 struct dma_async_tx_descriptor *
360 ioat_dma_prep_memcpy_lock(struct dma_chan *c, dma_addr_t dma_dest,
361 			   dma_addr_t dma_src, size_t len, unsigned long flags);
362 struct dma_async_tx_descriptor *
363 ioat_prep_interrupt_lock(struct dma_chan *c, unsigned long flags);
364 struct dma_async_tx_descriptor *
365 ioat_prep_xor(struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src,
366 	       unsigned int src_cnt, size_t len, unsigned long flags);
367 struct dma_async_tx_descriptor *
368 ioat_prep_xor_val(struct dma_chan *chan, dma_addr_t *src,
369 		    unsigned int src_cnt, size_t len,
370 		    enum sum_check_flags *result, unsigned long flags);
371 struct dma_async_tx_descriptor *
372 ioat_prep_pq(struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src,
373 	      unsigned int src_cnt, const unsigned char *scf, size_t len,
374 	      unsigned long flags);
375 struct dma_async_tx_descriptor *
376 ioat_prep_pq_val(struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src,
377 		  unsigned int src_cnt, const unsigned char *scf, size_t len,
378 		  enum sum_check_flags *pqres, unsigned long flags);
379 struct dma_async_tx_descriptor *
380 ioat_prep_pqxor(struct dma_chan *chan, dma_addr_t dst, dma_addr_t *src,
381 		 unsigned int src_cnt, size_t len, unsigned long flags);
382 struct dma_async_tx_descriptor *
383 ioat_prep_pqxor_val(struct dma_chan *chan, dma_addr_t *src,
384 		     unsigned int src_cnt, size_t len,
385 		     enum sum_check_flags *result, unsigned long flags);
386 
387 /* IOAT Operation functions */
388 irqreturn_t ioat_dma_do_interrupt(int irq, void *data);
389 irqreturn_t ioat_dma_do_interrupt_msix(int irq, void *data);
390 struct ioat_ring_ent **
391 ioat_alloc_ring(struct dma_chan *c, int order, gfp_t flags);
392 void ioat_start_null_desc(struct ioatdma_chan *ioat_chan);
393 void ioat_free_ring_ent(struct ioat_ring_ent *desc, struct dma_chan *chan);
394 int ioat_reset_hw(struct ioatdma_chan *ioat_chan);
395 enum dma_status
396 ioat_tx_status(struct dma_chan *c, dma_cookie_t cookie,
397 		struct dma_tx_state *txstate);
398 void ioat_cleanup_event(unsigned long data);
399 void ioat_timer_event(struct timer_list *t);
400 int ioat_check_space_lock(struct ioatdma_chan *ioat_chan, int num_descs);
401 void ioat_issue_pending(struct dma_chan *chan);
402 
403 /* IOAT Init functions */
404 bool is_bwd_ioat(struct pci_dev *pdev);
405 struct dca_provider *ioat_dca_init(struct pci_dev *pdev, void __iomem *iobase);
406 void ioat_kobject_add(struct ioatdma_device *ioat_dma, struct kobj_type *type);
407 void ioat_kobject_del(struct ioatdma_device *ioat_dma);
408 int ioat_dma_setup_interrupts(struct ioatdma_device *ioat_dma);
409 void ioat_stop(struct ioatdma_chan *ioat_chan);
410 #endif /* IOATDMA_H */
411