1 /* SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause */
2 /*
3  * Copyright(c) 2023 - Cornelis Networks, Inc.
4  * Copyright(c) 2015 - 2018 Intel Corporation.
5  */
6 #ifndef _HFI1_USER_SDMA_H
7 #define _HFI1_USER_SDMA_H
8 
9 #include <linux/device.h>
10 #include <linux/wait.h>
11 
12 #include "common.h"
13 #include "iowait.h"
14 #include "user_exp_rcv.h"
15 #include "mmu_rb.h"
16 #include "pinning.h"
17 #include "sdma.h"
18 
19 /* The maximum number of Data io vectors per message/request */
20 #define MAX_VECTORS_PER_REQ 8
21 /*
22  * Maximum number of packet to send from each message/request
23  * before moving to the next one.
24  */
25 #define MAX_PKTS_PER_QUEUE 16
26 
27 #define num_pages(x) (1 + ((((x) - 1) & PAGE_MASK) >> PAGE_SHIFT))
28 
29 #define req_opcode(x) \
30 	(((x) >> HFI1_SDMA_REQ_OPCODE_SHIFT) & HFI1_SDMA_REQ_OPCODE_MASK)
31 #define req_version(x) \
32 	(((x) >> HFI1_SDMA_REQ_VERSION_SHIFT) & HFI1_SDMA_REQ_OPCODE_MASK)
33 #define req_iovcnt(x) \
34 	(((x) >> HFI1_SDMA_REQ_IOVCNT_SHIFT) & HFI1_SDMA_REQ_IOVCNT_MASK)
35 
36 /* Number of BTH.PSN bits used for sequence number in expected rcvs */
37 #define BTH_SEQ_MASK 0x7ffull
38 
39 #define AHG_KDETH_INTR_SHIFT 12
40 #define AHG_KDETH_SH_SHIFT   13
41 #define AHG_KDETH_ARRAY_SIZE  9
42 
43 #define PBC2LRH(x) ((((x) & 0xfff) << 2) - 4)
44 #define LRH2PBC(x) ((((x) >> 2) + 1) & 0xfff)
45 
46 /**
47  * Build an SDMA AHG header update descriptor and save it to an array.
48  * @arr        - Array to save the descriptor to.
49  * @idx        - Index of the array at which the descriptor will be saved.
50  * @array_size - Size of the array arr.
51  * @dw         - Update index into the header in DWs.
52  * @bit        - Start bit.
53  * @width      - Field width.
54  * @value      - 16 bits of immediate data to write into the field.
55  * Returns -ERANGE if idx is invalid. If successful, returns the next index
56  * (idx + 1) of the array to be used for the next descriptor.
57  */
ahg_header_set(u32 * arr,int idx,size_t array_size,u8 dw,u8 bit,u8 width,u16 value)58 static inline int ahg_header_set(u32 *arr, int idx, size_t array_size,
59 				 u8 dw, u8 bit, u8 width, u16 value)
60 {
61 	if ((size_t)idx >= array_size)
62 		return -ERANGE;
63 	arr[idx++] = sdma_build_ahg_descriptor(value, dw, bit, width);
64 	return idx;
65 }
66 
67 /* Tx request flag bits */
68 #define TXREQ_FLAGS_REQ_ACK   BIT(0)      /* Set the ACK bit in the header */
69 #define TXREQ_FLAGS_REQ_DISABLE_SH BIT(1) /* Disable header suppression */
70 
71 enum pkt_q_sdma_state {
72 	SDMA_PKT_Q_ACTIVE,
73 	SDMA_PKT_Q_DEFERRED,
74 };
75 
76 #define SDMA_IOWAIT_TIMEOUT 1000 /* in milliseconds */
77 
78 #define SDMA_DBG(req, fmt, ...)				     \
79 	hfi1_cdbg(SDMA, "[%u:%u:%u:%u] " fmt, (req)->pq->dd->unit, \
80 		 (req)->pq->ctxt, (req)->pq->subctxt, (req)->info.comp_idx, \
81 		 ##__VA_ARGS__)
82 
83 struct hfi1_user_sdma_pkt_q {
84 	u16 ctxt;
85 	u16 subctxt;
86 	u16 n_max_reqs;
87 	atomic_t n_reqs;
88 	u16 reqidx;
89 	struct hfi1_devdata *dd;
90 	struct kmem_cache *txreq_cache;
91 	struct user_sdma_request *reqs;
92 	unsigned long *req_in_use;
93 	struct iowait busy;
94 	enum pkt_q_sdma_state state;
95 	wait_queue_head_t wait;
96 	unsigned long unpinned;
97 	struct mmu_rb_handler *handler;
98 	atomic_t n_locked;
99 };
100 
101 struct hfi1_user_sdma_comp_q {
102 	u16 nentries;
103 	struct hfi1_sdma_comp_entry *comps;
104 };
105 
106 struct user_sdma_iovec {
107 	struct list_head list;
108 	struct iovec iov;
109 	/*
110 	 * offset into the virtual address space of the vector at
111 	 * which we last left off.
112 	 */
113 	u64 offset;
114 };
115 
116 /* evict operation argument */
117 struct evict_data {
118 	u32 cleared;	/* count evicted so far */
119 	u32 target;	/* target count to evict */
120 };
121 
122 struct user_sdma_request {
123 	/* This is the original header from user space */
124 	struct hfi1_pkt_header hdr;
125 
126 	/* Read mostly fields */
127 	struct hfi1_user_sdma_pkt_q *pq ____cacheline_aligned_in_smp;
128 	struct hfi1_user_sdma_comp_q *cq;
129 	/*
130 	 * Pointer to the SDMA engine for this request.
131 	 * Since different request could be on different VLs,
132 	 * each request will need it's own engine pointer.
133 	 */
134 	struct sdma_engine *sde;
135 	struct sdma_req_info info;
136 	/* TID array values copied from the tid_iov vector */
137 	u32 *tids;
138 	/* total length of the data in the request */
139 	u32 data_len;
140 	/* number of elements copied to the tids array */
141 	u16 n_tids;
142 	/*
143 	 * We copy the iovs for this request (based on
144 	 * info.iovcnt). These are only the data vectors
145 	 */
146 	u8 data_iovs;
147 	s8 ahg_idx;
148 
149 	/* Writeable fields shared with interrupt */
150 	u16 seqcomp ____cacheline_aligned_in_smp;
151 	u16 seqsubmitted;
152 
153 	/* Send side fields */
154 	struct list_head txps ____cacheline_aligned_in_smp;
155 	u16 seqnum;
156 	/*
157 	 * KDETH.OFFSET (TID) field
158 	 * The offset can cover multiple packets, depending on the
159 	 * size of the TID entry.
160 	 */
161 	u32 tidoffset;
162 	/*
163 	 * KDETH.Offset (Eager) field
164 	 * We need to remember the initial value so the headers
165 	 * can be updated properly.
166 	 */
167 	u32 koffset;
168 	u32 sent;
169 	/* TID index copied from the tid_iov vector */
170 	u16 tididx;
171 	/* progress index moving along the iovs array */
172 	u8 iov_idx;
173 	u8 has_error;
174 
175 	struct user_sdma_iovec iovs[MAX_VECTORS_PER_REQ];
176 } ____cacheline_aligned_in_smp;
177 
178 /*
179  * A single txreq could span up to 3 physical pages when the MTU
180  * is sufficiently large (> 4K). Each of the IOV pointers also
181  * needs it's own set of flags so the vector has been handled
182  * independently of each other.
183  */
184 struct user_sdma_txreq {
185 	/* Packet header for the txreq */
186 	struct hfi1_pkt_header hdr;
187 	struct sdma_txreq txreq;
188 	struct list_head list;
189 	struct user_sdma_request *req;
190 	u16 flags;
191 	u16 seqnum;
192 };
193 
194 int hfi1_user_sdma_alloc_queues(struct hfi1_ctxtdata *uctxt,
195 				struct hfi1_filedata *fd);
196 int hfi1_user_sdma_free_queues(struct hfi1_filedata *fd,
197 			       struct hfi1_ctxtdata *uctxt);
198 int hfi1_user_sdma_process_request(struct hfi1_filedata *fd,
199 				   struct iovec *iovec, unsigned long dim,
200 				   unsigned long *count);
201 #endif /* _HFI1_USER_SDMA_H */
202