1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  * Copyright (C) 2014 Freescale Semiconductor
4  */
5 
6 #ifndef _FSL_QBMAN_BASE_H
7 #define _FSL_QBMAN_BASE_H
8 
9 /* Descriptor for a QBMan instance on the SoC. On partitions/targets that do not
10  * control this QBMan instance, these values may simply be place-holders. The
11  * idea is simply that we be able to distinguish between them, eg. so that SWP
12  * descriptors can identify which QBMan instance they belong to. */
13 struct qbman_block_desc {
14 	void *ccsr_reg_bar; /* CCSR register map */
15 	int irq_rerr;  /* Recoverable error interrupt line */
16 	int irq_nrerr; /* Non-recoverable error interrupt line */
17 };
18 
19 /* Descriptor for a QBMan software portal, expressed in terms that make sense to
20  * the user context. Ie. on MC, this information is likely to be true-physical,
21  * and instantiated statically at compile-time. On GPP, this information is
22  * likely to be obtained via "discovery" over a partition's "layerscape bus"
23  * (ie. in response to a MC portal command), and would take into account any
24  * virtualisation of the GPP user's address space and/or interrupt numbering. */
25 struct qbman_swp_desc {
26 	const struct qbman_block_desc *block; /* The QBMan instance */
27 	void *cena_bar; /* Cache-enabled portal register map */
28 	void *cinh_bar; /* Cache-inhibited portal register map */
29 };
30 
31 /* Driver object for managing a QBMan portal */
32 struct qbman_swp;
33 
34 /* Place-holder for FDs, we represent it via the simplest form that we need for
35  * now. Different overlays may be needed to support different options, etc. (It
36  * is impractical to define One True Struct, because the resulting encoding
37  * routines (lots of read-modify-writes) would be worst-case performance whether
38  * or not circumstances required them.)
39  *
40  * Note, as with all data-structures exchanged between software and hardware (be
41  * they located in the portal register map or DMA'd to and from main-memory),
42  * the driver ensures that the caller of the driver API sees the data-structures
43  * in host-endianness. "struct qbman_fd" is no exception. The 32-bit words
44  * contained within this structure are represented in host-endianness, even if
45  * hardware always treats them as little-endian. As such, if any of these fields
46  * are interpreted in a binary (rather than numerical) fashion by hardware
47  * blocks (eg. accelerators), then the user should be careful. We illustrate
48  * with an example;
49  *
50  * Suppose the desired behaviour of an accelerator is controlled by the "frc"
51  * field of the FDs that are sent to it. Suppose also that the behaviour desired
52  * by the user corresponds to an "frc" value which is expressed as the literal
53  * sequence of bytes 0xfe, 0xed, 0xab, and 0xba. So "frc" should be the 32-bit
54  * value in which 0xfe is the first byte and 0xba is the last byte, and as
55  * hardware is little-endian, this amounts to a 32-bit "value" of 0xbaabedfe. If
56  * the software is little-endian also, this can simply be achieved by setting
57  * frc=0xbaabedfe. On the other hand, if software is big-endian, it should set
58  * frc=0xfeedabba! The best away of avoiding trouble with this sort of thing is
59  * to treat the 32-bit words as numerical values, in which the offset of a field
60  * from the beginning of the first byte (as required or generated by hardware)
61  * is numerically encoded by a left-shift (ie. by raising the field to a
62  * corresponding power of 2).  Ie. in the current example, software could set
63  * "frc" in the following way, and it would work correctly on both little-endian
64  * and big-endian operation;
65  *    fd.frc = (0xfe << 0) | (0xed << 8) | (0xab << 16) | (0xba << 24);
66  */
67 struct qbman_fd {
68 	union {
69 		uint32_t words[8];
70 		struct qbman_fd_simple {
71 			uint32_t addr_lo;
72 			uint32_t addr_hi;
73 			uint32_t len;
74 			/* offset in the MS 16 bits, BPID in the LS 16 bits */
75 			uint32_t bpid_offset;
76 			uint32_t frc; /* frame context */
77 			/* "err", "va", "cbmt", "asal", [...] */
78 			uint32_t ctrl;
79 			/* flow context */
80 			uint32_t flc_lo;
81 			uint32_t flc_hi;
82 		} simple;
83 	};
84 };
85 
86 #endif /* !_FSL_QBMAN_BASE_H */
87