1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2025 Ruslan Bukin <br@bsdpad.com>
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28 /* Cache Block Operations. */
29
30 #include <sys/param.h>
31 #include <sys/systm.h>
32
33 #include <machine/cbo.h>
34
35 static void
cbo_zicbom_cpu_dcache_wbinv_range(vm_offset_t va,vm_size_t len)36 cbo_zicbom_cpu_dcache_wbinv_range(vm_offset_t va, vm_size_t len)
37 {
38 vm_offset_t addr;
39
40 /*
41 * A flush operation atomically performs a clean operation followed by
42 * an invalidate operation.
43 */
44
45 va &= ~(dcache_line_size - 1);
46 for (addr = va; addr < va + len; addr += dcache_line_size)
47 __asm __volatile(".option push; .option arch, +zicbom\n"
48 "cbo.flush (%0); .option pop\n" :: "r"(addr));
49 }
50
51 static void
cbo_zicbom_cpu_dcache_inv_range(vm_offset_t va,vm_size_t len)52 cbo_zicbom_cpu_dcache_inv_range(vm_offset_t va, vm_size_t len)
53 {
54 vm_offset_t addr;
55
56 /*
57 * An invalidate operation makes data from store operations performed by
58 * a set of non-coherent agents visible to the set of coherent agents at
59 * a point common to both sets by deallocating all copies of a cache
60 * block from the set of coherent caches up to that point.
61 */
62
63 va &= ~(dcache_line_size - 1);
64 for (addr = va; addr < va + len; addr += dcache_line_size)
65 __asm __volatile(".option push; .option arch, +zicbom\n"
66 "cbo.inval (%0); .option pop\n" :: "r"(addr));
67 }
68
69 static void
cbo_zicbom_cpu_dcache_wb_range(vm_offset_t va,vm_size_t len)70 cbo_zicbom_cpu_dcache_wb_range(vm_offset_t va, vm_size_t len)
71 {
72 vm_offset_t addr;
73
74 /*
75 * A clean operation makes data from store operations performed by the
76 * set of coherent agents visible to a set of non-coherent agents at a
77 * point common to both sets by performing a write transfer of a copy of
78 * a cache block to that point provided a coherent agent performed a
79 * store operation that modified the data in the cache block since the
80 * previous invalidate, clean, or flush operation on the cache block.
81 */
82
83 va &= ~(dcache_line_size - 1);
84 for (addr = va; addr < va + len; addr += dcache_line_size)
85 __asm __volatile(".option push; .option arch, +zicbom\n"
86 "cbo.clean (%0); .option pop\n" :: "r"(addr));
87 }
88
89 void
cbo_zicbom_setup_cache(int cbom_block_size)90 cbo_zicbom_setup_cache(int cbom_block_size)
91 {
92 struct riscv_cache_ops zicbom_ops;
93
94 if (cbom_block_size <= 0 || !powerof2(cbom_block_size)) {
95 printf("Zicbom: could not initialise (invalid cache line %d)\n",
96 cbom_block_size);
97 return;
98 }
99
100 zicbom_ops.dcache_wbinv_range = cbo_zicbom_cpu_dcache_wbinv_range;
101 zicbom_ops.dcache_inv_range = cbo_zicbom_cpu_dcache_inv_range;
102 zicbom_ops.dcache_wb_range = cbo_zicbom_cpu_dcache_wb_range;
103 riscv_cache_install_hooks(&zicbom_ops, cbom_block_size);
104 }
105