1 /*
2  * Copyright (C) 2014 Freescale Semiconductor
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #ifndef _FSL_QBMAN_BASE_H
8 #define _FSL_QBMAN_BASE_H
9 
10 /* Descriptor for a QBMan instance on the SoC. On partitions/targets that do not
11  * control this QBMan instance, these values may simply be place-holders. The
12  * idea is simply that we be able to distinguish between them, eg. so that SWP
13  * descriptors can identify which QBMan instance they belong to. */
14 struct qbman_block_desc {
15 	void *ccsr_reg_bar; /* CCSR register map */
16 	int irq_rerr;  /* Recoverable error interrupt line */
17 	int irq_nrerr; /* Non-recoverable error interrupt line */
18 };
19 
20 /* Descriptor for a QBMan software portal, expressed in terms that make sense to
21  * the user context. Ie. on MC, this information is likely to be true-physical,
22  * and instantiated statically at compile-time. On GPP, this information is
23  * likely to be obtained via "discovery" over a partition's "layerscape bus"
24  * (ie. in response to a MC portal command), and would take into account any
25  * virtualisation of the GPP user's address space and/or interrupt numbering. */
26 struct qbman_swp_desc {
27 	const struct qbman_block_desc *block; /* The QBMan instance */
28 	void *cena_bar; /* Cache-enabled portal register map */
29 	void *cinh_bar; /* Cache-inhibited portal register map */
30 };
31 
32 /* Driver object for managing a QBMan portal */
33 struct qbman_swp;
34 
35 /* Place-holder for FDs, we represent it via the simplest form that we need for
36  * now. Different overlays may be needed to support different options, etc. (It
37  * is impractical to define One True Struct, because the resulting encoding
38  * routines (lots of read-modify-writes) would be worst-case performance whether
39  * or not circumstances required them.)
40  *
41  * Note, as with all data-structures exchanged between software and hardware (be
42  * they located in the portal register map or DMA'd to and from main-memory),
43  * the driver ensures that the caller of the driver API sees the data-structures
44  * in host-endianness. "struct qbman_fd" is no exception. The 32-bit words
45  * contained within this structure are represented in host-endianness, even if
46  * hardware always treats them as little-endian. As such, if any of these fields
47  * are interpreted in a binary (rather than numerical) fashion by hardware
48  * blocks (eg. accelerators), then the user should be careful. We illustrate
49  * with an example;
50  *
51  * Suppose the desired behaviour of an accelerator is controlled by the "frc"
52  * field of the FDs that are sent to it. Suppose also that the behaviour desired
53  * by the user corresponds to an "frc" value which is expressed as the literal
54  * sequence of bytes 0xfe, 0xed, 0xab, and 0xba. So "frc" should be the 32-bit
55  * value in which 0xfe is the first byte and 0xba is the last byte, and as
56  * hardware is little-endian, this amounts to a 32-bit "value" of 0xbaabedfe. If
57  * the software is little-endian also, this can simply be achieved by setting
58  * frc=0xbaabedfe. On the other hand, if software is big-endian, it should set
59  * frc=0xfeedabba! The best away of avoiding trouble with this sort of thing is
60  * to treat the 32-bit words as numerical values, in which the offset of a field
61  * from the beginning of the first byte (as required or generated by hardware)
62  * is numerically encoded by a left-shift (ie. by raising the field to a
63  * corresponding power of 2).  Ie. in the current example, software could set
64  * "frc" in the following way, and it would work correctly on both little-endian
65  * and big-endian operation;
66  *    fd.frc = (0xfe << 0) | (0xed << 8) | (0xab << 16) | (0xba << 24);
67  */
68 struct qbman_fd {
69 	union {
70 		uint32_t words[8];
71 		struct qbman_fd_simple {
72 			uint32_t addr_lo;
73 			uint32_t addr_hi;
74 			uint32_t len;
75 			/* offset in the MS 16 bits, BPID in the LS 16 bits */
76 			uint32_t bpid_offset;
77 			uint32_t frc; /* frame context */
78 			/* "err", "va", "cbmt", "asal", [...] */
79 			uint32_t ctrl;
80 			/* flow context */
81 			uint32_t flc_lo;
82 			uint32_t flc_hi;
83 		} simple;
84 	};
85 };
86 
87 #endif /* !_FSL_QBMAN_BASE_H */
88