xref: /linux/arch/powerpc/include/asm/vas.h (revision 0d3b051adbb72ed81956447d0d1e54d5943ee6f5)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * Copyright 2016-17 IBM Corp.
4  */
5 
6 #ifndef _ASM_POWERPC_VAS_H
7 #define _ASM_POWERPC_VAS_H
8 
9 struct vas_window;
10 
11 /*
12  * Min and max FIFO sizes are based on Version 1.05 Section 3.1.4.25
13  * (Local FIFO Size Register) of the VAS workbook.
14  */
15 #define VAS_RX_FIFO_SIZE_MIN	(1 << 10)	/* 1KB */
16 #define VAS_RX_FIFO_SIZE_MAX	(8 << 20)	/* 8MB */
17 
18 /*
19  * Threshold Control Mode: Have paste operation fail if the number of
20  * requests in receive FIFO exceeds a threshold.
21  *
22  * NOTE: No special error code yet if paste is rejected because of these
23  *	 limits. So users can't distinguish between this and other errors.
24  */
25 #define VAS_THRESH_DISABLED		0
26 #define VAS_THRESH_FIFO_GT_HALF_FULL	1
27 #define VAS_THRESH_FIFO_GT_QTR_FULL	2
28 #define VAS_THRESH_FIFO_GT_EIGHTH_FULL	3
29 
30 /*
31  * Get/Set bit fields
32  */
33 #define GET_FIELD(m, v)                (((v) & (m)) >> MASK_LSH(m))
34 #define MASK_LSH(m)            (__builtin_ffsl(m) - 1)
35 #define SET_FIELD(m, v, val)   \
36 		(((v) & ~(m)) | ((((typeof(v))(val)) << MASK_LSH(m)) & (m)))
37 
38 /*
39  * Co-processor Engine type.
40  */
41 enum vas_cop_type {
42 	VAS_COP_TYPE_FAULT,
43 	VAS_COP_TYPE_842,
44 	VAS_COP_TYPE_842_HIPRI,
45 	VAS_COP_TYPE_GZIP,
46 	VAS_COP_TYPE_GZIP_HIPRI,
47 	VAS_COP_TYPE_FTW,
48 	VAS_COP_TYPE_MAX,
49 };
50 
51 /*
52  * Receive window attributes specified by the (in-kernel) owner of window.
53  */
54 struct vas_rx_win_attr {
55 	void *rx_fifo;
56 	int rx_fifo_size;
57 	int wcreds_max;
58 
59 	bool pin_win;
60 	bool rej_no_credit;
61 	bool tx_wcred_mode;
62 	bool rx_wcred_mode;
63 	bool tx_win_ord_mode;
64 	bool rx_win_ord_mode;
65 	bool data_stamp;
66 	bool nx_win;
67 	bool fault_win;
68 	bool user_win;
69 	bool notify_disable;
70 	bool intr_disable;
71 	bool notify_early;
72 
73 	int lnotify_lpid;
74 	int lnotify_pid;
75 	int lnotify_tid;
76 	u32 pswid;
77 
78 	int tc_mode;
79 };
80 
81 /*
82  * Window attributes specified by the in-kernel owner of a send window.
83  */
84 struct vas_tx_win_attr {
85 	enum vas_cop_type cop;
86 	int wcreds_max;
87 	int lpid;
88 	int pidr;		/* hardware PID (from SPRN_PID) */
89 	int pswid;
90 	int rsvd_txbuf_count;
91 	int tc_mode;
92 
93 	bool user_win;
94 	bool pin_win;
95 	bool rej_no_credit;
96 	bool rsvd_txbuf_enable;
97 	bool tx_wcred_mode;
98 	bool rx_wcred_mode;
99 	bool tx_win_ord_mode;
100 	bool rx_win_ord_mode;
101 };
102 
103 /*
104  * Helper to map a chip id to VAS id.
105  * For POWER9, this is a 1:1 mapping. In the future this maybe a 1:N
106  * mapping in which case, we will need to update this helper.
107  *
108  * Return the VAS id or -1 if no matching vasid is found.
109  */
110 int chip_to_vas_id(int chipid);
111 
112 /*
113  * Helper to initialize receive window attributes to defaults for an
114  * NX window.
115  */
116 void vas_init_rx_win_attr(struct vas_rx_win_attr *rxattr, enum vas_cop_type cop);
117 
118 /*
119  * Open a VAS receive window for the instance of VAS identified by @vasid
120  * Use @attr to initialize the attributes of the window.
121  *
122  * Return a handle to the window or ERR_PTR() on error.
123  */
124 struct vas_window *vas_rx_win_open(int vasid, enum vas_cop_type cop,
125 				   struct vas_rx_win_attr *attr);
126 
127 /*
128  * Helper to initialize send window attributes to defaults for an NX window.
129  */
130 extern void vas_init_tx_win_attr(struct vas_tx_win_attr *txattr,
131 			enum vas_cop_type cop);
132 
133 /*
134  * Open a VAS send window for the instance of VAS identified by @vasid
135  * and the co-processor type @cop. Use @attr to initialize attributes
136  * of the window.
137  *
138  * Note: The instance of VAS must already have an open receive window for
139  * the coprocessor type @cop.
140  *
141  * Return a handle to the send window or ERR_PTR() on error.
142  */
143 struct vas_window *vas_tx_win_open(int vasid, enum vas_cop_type cop,
144 			struct vas_tx_win_attr *attr);
145 
146 /*
147  * Close the send or receive window identified by @win. For receive windows
148  * return -EAGAIN if there are active send windows attached to this receive
149  * window.
150  */
151 int vas_win_close(struct vas_window *win);
152 
153 /*
154  * Copy the co-processor request block (CRB) @crb into the local L2 cache.
155  */
156 int vas_copy_crb(void *crb, int offset);
157 
158 /*
159  * Paste a previously copied CRB (see vas_copy_crb()) from the L2 cache to
160  * the hardware address associated with the window @win. @re is expected/
161  * assumed to be true for NX windows.
162  */
163 int vas_paste_crb(struct vas_window *win, int offset, bool re);
164 
165 /*
166  * Register / unregister coprocessor type to VAS API which will be exported
167  * to user space. Applications can use this API to open / close window
168  * which can be used to send / receive requests directly to cooprcessor.
169  *
170  * Only NX GZIP coprocessor type is supported now, but this API can be
171  * used for others in future.
172  */
173 int vas_register_coproc_api(struct module *mod, enum vas_cop_type cop_type,
174 				const char *name);
175 void vas_unregister_coproc_api(void);
176 
177 #endif /* __ASM_POWERPC_VAS_H */
178