xref: /freebsd/sys/dev/ioat/ioat.h (revision 685dc743)
1 /*-
2  * Copyright (C) 2012 Intel Corporation
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 #ifndef __IOAT_H__
27 #define __IOAT_H__
28 
29 #include <sys/param.h>
30 #include <machine/bus.h>
31 
32 /*
33  * This file defines the public interface to the IOAT driver.
34  */
35 
36 /*
37  * Enables an interrupt for this operation. Typically, you would only enable
38  * this on the last operation in a group
39  */
40 #define	DMA_INT_EN	0x1
41 /*
42  * Like M_NOWAIT.  Operations will return NULL if they cannot allocate a
43  * descriptor without blocking.
44  */
45 #define	DMA_NO_WAIT	0x2
46 /*
47  * Disallow prefetching the source of the following operation.  Ordinarily, DMA
48  * operations can be pipelined on some hardware.  E.g., operation 2's source
49  * may be prefetched before operation 1 completes.
50  */
51 #define	DMA_FENCE	0x4
52 #define	_DMA_GENERIC_FLAGS	(DMA_INT_EN | DMA_NO_WAIT | DMA_FENCE)
53 
54 /*
55  * Emit a CRC32C as the result of a ioat_copy_crc() or ioat_crc().
56  */
57 #define	DMA_CRC_STORE	0x8
58 
59 /*
60  * Compare the CRC32C of a ioat_copy_crc() or ioat_crc() against an expeceted
61  * value.  It is invalid to specify both TEST and STORE.
62  */
63 #define	DMA_CRC_TEST	0x10
64 #define	_DMA_CRC_TESTSTORE	(DMA_CRC_STORE | DMA_CRC_TEST)
65 
66 /*
67  * Use an inline comparison CRC32C or emit an inline CRC32C result.  Invalid
68  * without one of STORE or TEST.
69  */
70 #define	DMA_CRC_INLINE	0x20
71 #define	_DMA_CRC_FLAGS	(DMA_CRC_STORE | DMA_CRC_TEST | DMA_CRC_INLINE)
72 
73 /*
74  * Hardware revision number.  Different hardware revisions support different
75  * features.  For example, 3.2 cannot read from MMIO space, while 3.3 can.
76  */
77 #define	IOAT_VER_3_0			0x30
78 #define	IOAT_VER_3_2			0x32
79 #define	IOAT_VER_3_3			0x33
80 
81 /*
82  * Hardware capabilities.  Different hardware revisions support different
83  * features.  It is often useful to detect specific features than try to infer
84  * them from hardware version.
85  *
86  * Different channels may support different features too; for example, 'PQ' may
87  * only be supported on the first two channels of some hardware.
88  */
89 #define	IOAT_DMACAP_PB			(1 << 0)
90 #define	IOAT_DMACAP_CRC			(1 << 1)
91 #define	IOAT_DMACAP_MARKER_SKIP		(1 << 2)
92 #define	IOAT_DMACAP_OLD_XOR		(1 << 3)
93 #define	IOAT_DMACAP_DCA			(1 << 4)
94 #define	IOAT_DMACAP_MOVECRC		(1 << 5)
95 #define	IOAT_DMACAP_BFILL		(1 << 6)
96 #define	IOAT_DMACAP_EXT_APIC		(1 << 7)
97 #define	IOAT_DMACAP_XOR			(1 << 8)
98 #define	IOAT_DMACAP_PQ			(1 << 9)
99 #define	IOAT_DMACAP_DMA_DIF		(1 << 10)
100 #define	IOAT_DMACAP_DWBES		(1 << 13)
101 #define	IOAT_DMACAP_RAID16SS		(1 << 17)
102 #define	IOAT_DMACAP_DMAMC		(1 << 18)
103 #define	IOAT_DMACAP_CTOS		(1 << 19)
104 
105 #define	IOAT_DMACAP_STR \
106     "\20\24Completion_Timeout_Support\23DMA_with_Multicasting_Support" \
107     "\22RAID_Super_descriptors\16Descriptor_Write_Back_Error_Support" \
108     "\13DMA_with_DIF\12PQ\11XOR\10Extended_APIC_ID\07Block_Fill\06Move_CRC" \
109     "\05DCA\04Old_XOR\03Marker_Skipping\02CRC\01Page_Break"
110 
111 typedef void *bus_dmaengine_t;
112 struct bus_dmadesc;
113 typedef void (*bus_dmaengine_callback_t)(void *arg, int error);
114 
115 unsigned ioat_get_nchannels(void);
116 
117 /*
118  * Called first to acquire a reference to the DMA channel
119  *
120  * Flags may be M_WAITOK or M_NOWAIT.
121  */
122 bus_dmaengine_t ioat_get_dmaengine(uint32_t channel_index, int flags);
123 
124 /* Release the DMA channel */
125 void ioat_put_dmaengine(bus_dmaengine_t dmaengine);
126 
127 /* Check the DMA engine's HW version */
128 int ioat_get_hwversion(bus_dmaengine_t dmaengine);
129 size_t ioat_get_max_io_size(bus_dmaengine_t dmaengine);
130 uint32_t ioat_get_capabilities(bus_dmaengine_t dmaengine);
131 int ioat_get_domain(bus_dmaengine_t dmaengine, int *domain);
132 
133 /*
134  * Set interrupt coalescing on a DMA channel.
135  *
136  * The argument is in microseconds.  A zero value disables coalescing.  Any
137  * other value delays interrupt generation for N microseconds to provide
138  * opportunity to coalesce multiple operations into a single interrupt.
139  *
140  * Returns an error status, or zero on success.
141  *
142  * - ERANGE if the given value exceeds the delay supported by the hardware.
143  *   (All current hardware supports a maximum of 0x3fff microseconds delay.)
144  * - ENODEV if the hardware does not support interrupt coalescing.
145  */
146 int ioat_set_interrupt_coalesce(bus_dmaengine_t dmaengine, uint16_t delay);
147 
148 /*
149  * Return the maximum supported coalescing period, for use in
150  * ioat_set_interrupt_coalesce().  If the hardware does not support coalescing,
151  * returns zero.
152  */
153 uint16_t ioat_get_max_coalesce_period(bus_dmaengine_t dmaengine);
154 
155 /*
156  * Acquire must be called before issuing an operation to perform. Release is
157  * called after.  Multiple operations can be issued within the context of one
158  * acquire and release
159  */
160 void ioat_acquire(bus_dmaengine_t dmaengine);
161 void ioat_release(bus_dmaengine_t dmaengine);
162 
163 /*
164  * Acquire_reserve can be called to ensure there is room for N descriptors.  If
165  * it succeeds, the next N valid operations will successfully enqueue.
166  *
167  * It may fail with:
168  *   - ENXIO if the channel is in an errored state, or the driver is being
169  *     unloaded
170  *   - EAGAIN if mflags included M_NOWAIT
171  *
172  * On failure, the caller does not hold the dmaengine.
173  */
174 int ioat_acquire_reserve(bus_dmaengine_t dmaengine, unsigned n, int mflags)
175     __result_use_check;
176 
177 /*
178  * Issue a blockfill operation.  The 64-bit pattern 'fillpattern' is written to
179  * 'len' physically contiguous bytes at 'dst'.
180  *
181  * Only supported on devices with the BFILL capability.
182  */
183 struct bus_dmadesc *ioat_blockfill(bus_dmaengine_t dmaengine, bus_addr_t dst,
184     uint64_t fillpattern, bus_size_t len, bus_dmaengine_callback_t callback_fn,
185     void *callback_arg, uint32_t flags);
186 
187 /* Issues the copy data operation */
188 struct bus_dmadesc *ioat_copy(bus_dmaengine_t dmaengine, bus_addr_t dst,
189     bus_addr_t src, bus_size_t len, bus_dmaengine_callback_t callback_fn,
190     void *callback_arg, uint32_t flags);
191 
192 /*
193  * Issue a copy data operation, with constraints:
194  *  - src1, src2, dst1, dst2 are all page-aligned addresses
195  *  - The quantity to copy is exactly 2 pages;
196  *  - src1 -> dst1, src2 -> dst2
197  *
198  * Why use this instead of normal _copy()?  You can copy two non-contiguous
199  * pages (src, dst, or both) with one descriptor.
200  */
201 struct bus_dmadesc *ioat_copy_8k_aligned(bus_dmaengine_t dmaengine,
202     bus_addr_t dst1, bus_addr_t dst2, bus_addr_t src1, bus_addr_t src2,
203     bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags);
204 
205 /*
206  * Copy len bytes from dst to src, like ioat_copy().
207  *
208  * Additionally, accumulate a CRC32C of the data.
209  *
210  * If initialseed is not NULL, the value it points to is used to seed the
211  * initial value of the CRC32C.
212  *
213  * If flags include DMA_CRC_STORE and not DMA_CRC_INLINE, crcptr is written
214  * with the 32-bit CRC32C result (in wire format).
215  *
216  * If flags include DMA_CRC_TEST and not DMA_CRC_INLINE, the computed CRC32C is
217  * compared with the 32-bit CRC32C pointed to by crcptr.  If they do not match,
218  * a channel error is raised.
219  *
220  * If the DMA_CRC_INLINE flag is set, crcptr is ignored and the DMA engine uses
221  * the 4 bytes trailing the source data (TEST) or the destination data (STORE).
222  */
223 struct bus_dmadesc *ioat_copy_crc(bus_dmaengine_t dmaengine, bus_addr_t dst,
224     bus_addr_t src, bus_size_t len, uint32_t *initialseed, bus_addr_t crcptr,
225     bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags);
226 
227 /*
228  * ioat_crc() is nearly identical to ioat_copy_crc(), but does not actually
229  * move data around.
230  *
231  * Like ioat_copy_crc, ioat_crc computes a CRC32C over len bytes pointed to by
232  * src.  The flags affect its operation in the same way, with one exception:
233  *
234  * If flags includes both DMA_CRC_STORE and DMA_CRC_INLINE, the computed CRC32C
235  * is written to the 4 bytes trailing the *source* data.
236  */
237 struct bus_dmadesc *ioat_crc(bus_dmaengine_t dmaengine, bus_addr_t src,
238     bus_size_t len, uint32_t *initialseed, bus_addr_t crcptr,
239     bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags);
240 
241 /*
242  * Issues a null operation. This issues the operation to the hardware, but the
243  * hardware doesn't do anything with it.
244  */
245 struct bus_dmadesc *ioat_null(bus_dmaengine_t dmaengine,
246     bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags);
247 
248 
249 #endif /* __IOAT_H__ */
250 
251