xref: /openbmc/linux/drivers/dma/ioat/dma.h (revision b868a02e)
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 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 	struct ioat_descs descs[IOAT_MAX_DESCS / IOAT_DESCS_PER_CHUNK];
135 	int desc_chunks;
136 	int intr_coalesce;
137 	int prev_intr_coalesce;
138 };
139 
140 struct ioat_sysfs_entry {
141 	struct attribute attr;
142 	ssize_t (*show)(struct dma_chan *, char *);
143 	ssize_t (*store)(struct dma_chan *, const char *, size_t);
144 };
145 
146 /**
147  * struct ioat_sed_ent - wrapper around super extended hardware descriptor
148  * @hw: hardware SED
149  * @dma: dma address for the SED
150  * @parent: point to the dma descriptor that's the parent
151  * @hw_pool: descriptor pool index
152  */
153 struct ioat_sed_ent {
154 	struct ioat_sed_raw_descriptor *hw;
155 	dma_addr_t dma;
156 	struct ioat_ring_ent *parent;
157 	unsigned int hw_pool;
158 };
159 
160 /**
161  * struct ioat_ring_ent - wrapper around hardware descriptor
162  * @hw: hardware DMA descriptor (for memcpy)
163  * @xor: hardware xor descriptor
164  * @xor_ex: hardware xor extension descriptor
165  * @pq: hardware pq descriptor
166  * @pq_ex: hardware pq extension descriptor
167  * @pqu: hardware pq update descriptor
168  * @raw: hardware raw (un-typed) descriptor
169  * @txd: the generic software descriptor for all engines
170  * @len: total transaction length for unmap
171  * @result: asynchronous result of validate operations
172  * @id: identifier for debug
173  * @sed: pointer to super extended descriptor sw desc
174  */
175 
176 struct ioat_ring_ent {
177 	union {
178 		struct ioat_dma_descriptor *hw;
179 		struct ioat_xor_descriptor *xor;
180 		struct ioat_xor_ext_descriptor *xor_ex;
181 		struct ioat_pq_descriptor *pq;
182 		struct ioat_pq_ext_descriptor *pq_ex;
183 		struct ioat_pq_update_descriptor *pqu;
184 		struct ioat_raw_descriptor *raw;
185 	};
186 	size_t len;
187 	struct dma_async_tx_descriptor txd;
188 	enum sum_check_flags *result;
189 	#ifdef DEBUG
190 	int id;
191 	#endif
192 	struct ioat_sed_ent *sed;
193 };
194 
195 extern const struct sysfs_ops ioat_sysfs_ops;
196 extern struct ioat_sysfs_entry ioat_version_attr;
197 extern struct ioat_sysfs_entry ioat_cap_attr;
198 extern int ioat_pending_level;
199 extern struct kobj_type ioat_ktype;
200 extern struct kmem_cache *ioat_cache;
201 extern struct kmem_cache *ioat_sed_cache;
202 
203 static inline struct ioatdma_chan *to_ioat_chan(struct dma_chan *c)
204 {
205 	return container_of(c, struct ioatdma_chan, dma_chan);
206 }
207 
208 /* wrapper around hardware descriptor format + additional software fields */
209 #ifdef DEBUG
210 #define set_desc_id(desc, i) ((desc)->id = (i))
211 #define desc_id(desc) ((desc)->id)
212 #else
213 #define set_desc_id(desc, i)
214 #define desc_id(desc) (0)
215 #endif
216 
217 static inline void
218 __dump_desc_dbg(struct ioatdma_chan *ioat_chan, struct ioat_dma_descriptor *hw,
219 		struct dma_async_tx_descriptor *tx, int id)
220 {
221 	struct device *dev = to_dev(ioat_chan);
222 
223 	dev_dbg(dev, "desc[%d]: (%#llx->%#llx) cookie: %d flags: %#x"
224 		" ctl: %#10.8x (op: %#x int_en: %d compl: %d)\n", id,
225 		(unsigned long long) tx->phys,
226 		(unsigned long long) hw->next, tx->cookie, tx->flags,
227 		hw->ctl, hw->ctl_f.op, hw->ctl_f.int_en, hw->ctl_f.compl_write);
228 }
229 
230 #define dump_desc_dbg(c, d) \
231 	({ if (d) __dump_desc_dbg(c, d->hw, &d->txd, desc_id(d)); 0; })
232 
233 static inline struct ioatdma_chan *
234 ioat_chan_by_index(struct ioatdma_device *ioat_dma, int index)
235 {
236 	return ioat_dma->idx[index];
237 }
238 
239 static inline u64 ioat_chansts(struct ioatdma_chan *ioat_chan)
240 {
241 	return readq(ioat_chan->reg_base + IOAT_CHANSTS_OFFSET);
242 }
243 
244 static inline u64 ioat_chansts_to_addr(u64 status)
245 {
246 	return status & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_ADDR;
247 }
248 
249 static inline u32 ioat_chanerr(struct ioatdma_chan *ioat_chan)
250 {
251 	return readl(ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
252 }
253 
254 static inline void ioat_suspend(struct ioatdma_chan *ioat_chan)
255 {
256 	u8 ver = ioat_chan->ioat_dma->version;
257 
258 	writeb(IOAT_CHANCMD_SUSPEND,
259 	       ioat_chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
260 }
261 
262 static inline void ioat_reset(struct ioatdma_chan *ioat_chan)
263 {
264 	u8 ver = ioat_chan->ioat_dma->version;
265 
266 	writeb(IOAT_CHANCMD_RESET,
267 	       ioat_chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
268 }
269 
270 static inline bool ioat_reset_pending(struct ioatdma_chan *ioat_chan)
271 {
272 	u8 ver = ioat_chan->ioat_dma->version;
273 	u8 cmd;
274 
275 	cmd = readb(ioat_chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
276 	return (cmd & IOAT_CHANCMD_RESET) == IOAT_CHANCMD_RESET;
277 }
278 
279 static inline bool is_ioat_active(unsigned long status)
280 {
281 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_ACTIVE);
282 }
283 
284 static inline bool is_ioat_idle(unsigned long status)
285 {
286 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_DONE);
287 }
288 
289 static inline bool is_ioat_halted(unsigned long status)
290 {
291 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_HALTED);
292 }
293 
294 static inline bool is_ioat_suspended(unsigned long status)
295 {
296 	return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_SUSPENDED);
297 }
298 
299 /* channel was fatally programmed */
300 static inline bool is_ioat_bug(unsigned long err)
301 {
302 	return !!err;
303 }
304 
305 
306 static inline u32 ioat_ring_size(struct ioatdma_chan *ioat_chan)
307 {
308 	return 1 << ioat_chan->alloc_order;
309 }
310 
311 /* count of descriptors in flight with the engine */
312 static inline u16 ioat_ring_active(struct ioatdma_chan *ioat_chan)
313 {
314 	return CIRC_CNT(ioat_chan->head, ioat_chan->tail,
315 			ioat_ring_size(ioat_chan));
316 }
317 
318 /* count of descriptors pending submission to hardware */
319 static inline u16 ioat_ring_pending(struct ioatdma_chan *ioat_chan)
320 {
321 	return CIRC_CNT(ioat_chan->head, ioat_chan->issued,
322 			ioat_ring_size(ioat_chan));
323 }
324 
325 static inline u32 ioat_ring_space(struct ioatdma_chan *ioat_chan)
326 {
327 	return ioat_ring_size(ioat_chan) - ioat_ring_active(ioat_chan);
328 }
329 
330 static inline u16
331 ioat_xferlen_to_descs(struct ioatdma_chan *ioat_chan, size_t len)
332 {
333 	u16 num_descs = len >> ioat_chan->xfercap_log;
334 
335 	num_descs += !!(len & ((1 << ioat_chan->xfercap_log) - 1));
336 	return num_descs;
337 }
338 
339 static inline struct ioat_ring_ent *
340 ioat_get_ring_ent(struct ioatdma_chan *ioat_chan, u16 idx)
341 {
342 	return ioat_chan->ring[idx & (ioat_ring_size(ioat_chan) - 1)];
343 }
344 
345 static inline void
346 ioat_set_chainaddr(struct ioatdma_chan *ioat_chan, u64 addr)
347 {
348 	writel(addr & 0x00000000FFFFFFFF,
349 	       ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_LOW);
350 	writel(addr >> 32,
351 	       ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_HIGH);
352 }
353 
354 /* IOAT Prep functions */
355 struct dma_async_tx_descriptor *
356 ioat_dma_prep_memcpy_lock(struct dma_chan *c, dma_addr_t dma_dest,
357 			   dma_addr_t dma_src, size_t len, unsigned long flags);
358 struct dma_async_tx_descriptor *
359 ioat_prep_interrupt_lock(struct dma_chan *c, unsigned long flags);
360 struct dma_async_tx_descriptor *
361 ioat_prep_xor(struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src,
362 	       unsigned int src_cnt, size_t len, unsigned long flags);
363 struct dma_async_tx_descriptor *
364 ioat_prep_xor_val(struct dma_chan *chan, dma_addr_t *src,
365 		    unsigned int src_cnt, size_t len,
366 		    enum sum_check_flags *result, unsigned long flags);
367 struct dma_async_tx_descriptor *
368 ioat_prep_pq(struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src,
369 	      unsigned int src_cnt, const unsigned char *scf, size_t len,
370 	      unsigned long flags);
371 struct dma_async_tx_descriptor *
372 ioat_prep_pq_val(struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src,
373 		  unsigned int src_cnt, const unsigned char *scf, size_t len,
374 		  enum sum_check_flags *pqres, unsigned long flags);
375 struct dma_async_tx_descriptor *
376 ioat_prep_pqxor(struct dma_chan *chan, dma_addr_t dst, dma_addr_t *src,
377 		 unsigned int src_cnt, size_t len, unsigned long flags);
378 struct dma_async_tx_descriptor *
379 ioat_prep_pqxor_val(struct dma_chan *chan, dma_addr_t *src,
380 		     unsigned int src_cnt, size_t len,
381 		     enum sum_check_flags *result, unsigned long flags);
382 
383 /* IOAT Operation functions */
384 irqreturn_t ioat_dma_do_interrupt(int irq, void *data);
385 irqreturn_t ioat_dma_do_interrupt_msix(int irq, void *data);
386 struct ioat_ring_ent **
387 ioat_alloc_ring(struct dma_chan *c, int order, gfp_t flags);
388 void ioat_start_null_desc(struct ioatdma_chan *ioat_chan);
389 void ioat_free_ring_ent(struct ioat_ring_ent *desc, struct dma_chan *chan);
390 int ioat_reset_hw(struct ioatdma_chan *ioat_chan);
391 enum dma_status
392 ioat_tx_status(struct dma_chan *c, dma_cookie_t cookie,
393 		struct dma_tx_state *txstate);
394 void ioat_cleanup_event(struct tasklet_struct *t);
395 void ioat_timer_event(struct timer_list *t);
396 int ioat_check_space_lock(struct ioatdma_chan *ioat_chan, int num_descs);
397 void ioat_issue_pending(struct dma_chan *chan);
398 
399 /* IOAT Init functions */
400 bool is_bwd_ioat(struct pci_dev *pdev);
401 struct dca_provider *ioat_dca_init(struct pci_dev *pdev, void __iomem *iobase);
402 void ioat_kobject_add(struct ioatdma_device *ioat_dma, struct kobj_type *type);
403 void ioat_kobject_del(struct ioatdma_device *ioat_dma);
404 int ioat_dma_setup_interrupts(struct ioatdma_device *ioat_dma);
405 void ioat_stop(struct ioatdma_chan *ioat_chan);
406 #endif /* IOATDMA_H */
407