xref: /openbmc/linux/drivers/dma/ioat/dma.h (revision 18afb028)
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 	int chancnt;
78 
79 	/* shadow version for CB3.3 chan reset errata workaround */
80 	u64 msixtba0;
81 	u64 msixdata0;
82 	u32 msixpba;
83 };
84 
85 #define IOAT_MAX_ORDER 16
86 #define IOAT_MAX_DESCS (1 << IOAT_MAX_ORDER)
87 #define IOAT_CHUNK_SIZE (SZ_512K)
88 #define IOAT_DESCS_PER_CHUNK (IOAT_CHUNK_SIZE / IOAT_DESC_SZ)
89 
90 struct ioat_descs {
91 	void *virt;
92 	dma_addr_t hw;
93 };
94 
95 struct ioatdma_chan {
96 	struct dma_chan dma_chan;
97 	void __iomem *reg_base;
98 	dma_addr_t last_completion;
99 	spinlock_t cleanup_lock;
100 	unsigned long state;
101 	#define IOAT_CHAN_DOWN 0
102 	#define IOAT_COMPLETION_ACK 1
103 	#define IOAT_RESET_PENDING 2
104 	#define IOAT_KOBJ_INIT_FAIL 3
105 	#define IOAT_RUN 5
106 	#define IOAT_CHAN_ACTIVE 6
107 	struct timer_list timer;
108 	#define RESET_DELAY msecs_to_jiffies(100)
109 	struct ioatdma_device *ioat_dma;
110 	dma_addr_t completion_dma;
111 	u64 *completion;
112 	struct tasklet_struct cleanup_task;
113 	struct kobject kobj;
114 
115 /* ioat v2 / v3 channel attributes
116  * @xfercap_log; log2 of channel max transfer length (for fast division)
117  * @head: allocated index
118  * @issued: hardware notification point
119  * @tail: cleanup index
120  * @dmacount: identical to 'head' except for occasionally resetting to zero
121  * @alloc_order: log2 of the number of allocated descriptors
122  * @produce: number of descriptors to produce at submit time
123  * @ring: software ring buffer implementation of hardware ring
124  * @prep_lock: serializes descriptor preparation (producers)
125  */
126 	size_t xfercap_log;
127 	u16 head;
128 	u16 issued;
129 	u16 tail;
130 	u16 dmacount;
131 	u16 alloc_order;
132 	u16 produce;
133 	struct ioat_ring_ent **ring;
134 	spinlock_t prep_lock;
135 	struct ioat_descs descs[IOAT_MAX_DESCS / IOAT_DESCS_PER_CHUNK];
136 	int desc_chunks;
137 	int intr_coalesce;
138 	int prev_intr_coalesce;
139 };
140 
141 struct ioat_sysfs_entry {
142 	struct attribute attr;
143 	ssize_t (*show)(struct dma_chan *, char *);
144 	ssize_t (*store)(struct dma_chan *, const char *, size_t);
145 };
146 
147 /**
148  * struct ioat_sed_ent - wrapper around super extended hardware descriptor
149  * @hw: hardware SED
150  * @dma: dma address for the SED
151  * @parent: point to the dma descriptor that's the parent
152  * @hw_pool: descriptor pool index
153  */
154 struct ioat_sed_ent {
155 	struct ioat_sed_raw_descriptor *hw;
156 	dma_addr_t dma;
157 	struct ioat_ring_ent *parent;
158 	unsigned int hw_pool;
159 };
160 
161 /**
162  * struct ioat_ring_ent - wrapper around hardware descriptor
163  * @hw: hardware DMA descriptor (for memcpy)
164  * @xor: hardware xor descriptor
165  * @xor_ex: hardware xor extension descriptor
166  * @pq: hardware pq descriptor
167  * @pq_ex: hardware pq extension descriptor
168  * @pqu: hardware pq update descriptor
169  * @raw: hardware raw (un-typed) descriptor
170  * @txd: the generic software descriptor for all engines
171  * @len: total transaction length for unmap
172  * @result: asynchronous result of validate operations
173  * @id: identifier for debug
174  * @sed: pointer to super extended descriptor sw desc
175  */
176 
177 struct ioat_ring_ent {
178 	union {
179 		struct ioat_dma_descriptor *hw;
180 		struct ioat_xor_descriptor *xor;
181 		struct ioat_xor_ext_descriptor *xor_ex;
182 		struct ioat_pq_descriptor *pq;
183 		struct ioat_pq_ext_descriptor *pq_ex;
184 		struct ioat_pq_update_descriptor *pqu;
185 		struct ioat_raw_descriptor *raw;
186 	};
187 	size_t len;
188 	struct dma_async_tx_descriptor txd;
189 	enum sum_check_flags *result;
190 	#ifdef DEBUG
191 	int id;
192 	#endif
193 	struct ioat_sed_ent *sed;
194 };
195 
196 extern const struct sysfs_ops ioat_sysfs_ops;
197 extern struct ioat_sysfs_entry ioat_version_attr;
198 extern struct ioat_sysfs_entry ioat_cap_attr;
199 extern int ioat_pending_level;
200 extern struct kobj_type ioat_ktype;
201 extern struct kmem_cache *ioat_cache;
202 extern struct kmem_cache *ioat_sed_cache;
203 
204 static inline struct ioatdma_chan *to_ioat_chan(struct dma_chan *c)
205 {
206 	return container_of(c, struct ioatdma_chan, dma_chan);
207 }
208 
209 /* wrapper around hardware descriptor format + additional software fields */
210 #ifdef DEBUG
211 #define set_desc_id(desc, i) ((desc)->id = (i))
212 #define desc_id(desc) ((desc)->id)
213 #else
214 #define set_desc_id(desc, i)
215 #define desc_id(desc) (0)
216 #endif
217 
218 static inline void
219 __dump_desc_dbg(struct ioatdma_chan *ioat_chan, struct ioat_dma_descriptor *hw,
220 		struct dma_async_tx_descriptor *tx, int id)
221 {
222 	struct device *dev = to_dev(ioat_chan);
223 
224 	dev_dbg(dev, "desc[%d]: (%#llx->%#llx) cookie: %d flags: %#x"
225 		" ctl: %#10.8x (op: %#x int_en: %d compl: %d)\n", id,
226 		(unsigned long long) tx->phys,
227 		(unsigned long long) hw->next, tx->cookie, tx->flags,
228 		hw->ctl, hw->ctl_f.op, hw->ctl_f.int_en, hw->ctl_f.compl_write);
229 }
230 
231 #define dump_desc_dbg(c, d) \
232 	({ if (d) __dump_desc_dbg(c, d->hw, &d->txd, desc_id(d)); 0; })
233 
234 static inline struct ioatdma_chan *
235 ioat_chan_by_index(struct ioatdma_device *ioat_dma, int index)
236 {
237 	return ioat_dma->idx[index];
238 }
239 
240 static inline u64 ioat_chansts(struct ioatdma_chan *ioat_chan)
241 {
242 	return readq(ioat_chan->reg_base + IOAT_CHANSTS_OFFSET);
243 }
244 
245 static inline u64 ioat_chansts_to_addr(u64 status)
246 {
247 	return status & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_ADDR;
248 }
249 
250 static inline u32 ioat_chanerr(struct ioatdma_chan *ioat_chan)
251 {
252 	return readl(ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
253 }
254 
255 static inline void ioat_suspend(struct ioatdma_chan *ioat_chan)
256 {
257 	u8 ver = ioat_chan->ioat_dma->version;
258 
259 	writeb(IOAT_CHANCMD_SUSPEND,
260 	       ioat_chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
261 }
262 
263 static inline void ioat_reset(struct ioatdma_chan *ioat_chan)
264 {
265 	u8 ver = ioat_chan->ioat_dma->version;
266 
267 	writeb(IOAT_CHANCMD_RESET,
268 	       ioat_chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
269 }
270 
271 static inline bool ioat_reset_pending(struct ioatdma_chan *ioat_chan)
272 {
273 	u8 ver = ioat_chan->ioat_dma->version;
274 	u8 cmd;
275 
276 	cmd = readb(ioat_chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
277 	return (cmd & IOAT_CHANCMD_RESET) == IOAT_CHANCMD_RESET;
278 }
279 
280 static inline bool is_ioat_active(unsigned long status)
281 {
282 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_ACTIVE);
283 }
284 
285 static inline bool is_ioat_idle(unsigned long status)
286 {
287 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_DONE);
288 }
289 
290 static inline bool is_ioat_halted(unsigned long status)
291 {
292 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_HALTED);
293 }
294 
295 static inline bool is_ioat_suspended(unsigned long status)
296 {
297 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_SUSPENDED);
298 }
299 
300 /* channel was fatally programmed */
301 static inline bool is_ioat_bug(unsigned long err)
302 {
303 	return !!err;
304 }
305 
306 
307 static inline u32 ioat_ring_size(struct ioatdma_chan *ioat_chan)
308 {
309 	return 1 << ioat_chan->alloc_order;
310 }
311 
312 /* count of descriptors in flight with the engine */
313 static inline u16 ioat_ring_active(struct ioatdma_chan *ioat_chan)
314 {
315 	return CIRC_CNT(ioat_chan->head, ioat_chan->tail,
316 			ioat_ring_size(ioat_chan));
317 }
318 
319 /* count of descriptors pending submission to hardware */
320 static inline u16 ioat_ring_pending(struct ioatdma_chan *ioat_chan)
321 {
322 	return CIRC_CNT(ioat_chan->head, ioat_chan->issued,
323 			ioat_ring_size(ioat_chan));
324 }
325 
326 static inline u32 ioat_ring_space(struct ioatdma_chan *ioat_chan)
327 {
328 	return ioat_ring_size(ioat_chan) - ioat_ring_active(ioat_chan);
329 }
330 
331 static inline u16
332 ioat_xferlen_to_descs(struct ioatdma_chan *ioat_chan, size_t len)
333 {
334 	u16 num_descs = len >> ioat_chan->xfercap_log;
335 
336 	num_descs += !!(len & ((1 << ioat_chan->xfercap_log) - 1));
337 	return num_descs;
338 }
339 
340 static inline struct ioat_ring_ent *
341 ioat_get_ring_ent(struct ioatdma_chan *ioat_chan, u16 idx)
342 {
343 	return ioat_chan->ring[idx & (ioat_ring_size(ioat_chan) - 1)];
344 }
345 
346 static inline void
347 ioat_set_chainaddr(struct ioatdma_chan *ioat_chan, u64 addr)
348 {
349 	writel(addr & 0x00000000FFFFFFFF,
350 	       ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_LOW);
351 	writel(addr >> 32,
352 	       ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_HIGH);
353 }
354 
355 /* IOAT Prep functions */
356 struct dma_async_tx_descriptor *
357 ioat_dma_prep_memcpy_lock(struct dma_chan *c, dma_addr_t dma_dest,
358 			   dma_addr_t dma_src, size_t len, unsigned long flags);
359 struct dma_async_tx_descriptor *
360 ioat_prep_interrupt_lock(struct dma_chan *c, unsigned long flags);
361 struct dma_async_tx_descriptor *
362 ioat_prep_xor(struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src,
363 	       unsigned int src_cnt, size_t len, unsigned long flags);
364 struct dma_async_tx_descriptor *
365 ioat_prep_xor_val(struct dma_chan *chan, dma_addr_t *src,
366 		    unsigned int src_cnt, size_t len,
367 		    enum sum_check_flags *result, unsigned long flags);
368 struct dma_async_tx_descriptor *
369 ioat_prep_pq(struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src,
370 	      unsigned int src_cnt, const unsigned char *scf, size_t len,
371 	      unsigned long flags);
372 struct dma_async_tx_descriptor *
373 ioat_prep_pq_val(struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src,
374 		  unsigned int src_cnt, const unsigned char *scf, size_t len,
375 		  enum sum_check_flags *pqres, unsigned long flags);
376 struct dma_async_tx_descriptor *
377 ioat_prep_pqxor(struct dma_chan *chan, dma_addr_t dst, dma_addr_t *src,
378 		 unsigned int src_cnt, size_t len, unsigned long flags);
379 struct dma_async_tx_descriptor *
380 ioat_prep_pqxor_val(struct dma_chan *chan, dma_addr_t *src,
381 		     unsigned int src_cnt, size_t len,
382 		     enum sum_check_flags *result, unsigned long flags);
383 
384 /* IOAT Operation functions */
385 irqreturn_t ioat_dma_do_interrupt(int irq, void *data);
386 irqreturn_t ioat_dma_do_interrupt_msix(int irq, void *data);
387 struct ioat_ring_ent **
388 ioat_alloc_ring(struct dma_chan *c, int order, gfp_t flags);
389 void ioat_start_null_desc(struct ioatdma_chan *ioat_chan);
390 void ioat_free_ring_ent(struct ioat_ring_ent *desc, struct dma_chan *chan);
391 int ioat_reset_hw(struct ioatdma_chan *ioat_chan);
392 enum dma_status
393 ioat_tx_status(struct dma_chan *c, dma_cookie_t cookie,
394 		struct dma_tx_state *txstate);
395 void ioat_cleanup_event(struct tasklet_struct *t);
396 void ioat_timer_event(struct timer_list *t);
397 int ioat_check_space_lock(struct ioatdma_chan *ioat_chan, int num_descs);
398 void ioat_issue_pending(struct dma_chan *chan);
399 
400 /* IOAT Init functions */
401 bool is_bwd_ioat(struct pci_dev *pdev);
402 struct dca_provider *ioat_dca_init(struct pci_dev *pdev, void __iomem *iobase);
403 void ioat_kobject_add(struct ioatdma_device *ioat_dma, struct kobj_type *type);
404 void ioat_kobject_del(struct ioatdma_device *ioat_dma);
405 int ioat_dma_setup_interrupts(struct ioatdma_device *ioat_dma);
406 void ioat_stop(struct ioatdma_chan *ioat_chan);
407 #endif /* IOATDMA_H */
408