1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2014 Juergen Weiss <weiss@uni-mainz.de>
5 * Copyright (c) 2014 Ian Lepore <ian@freebsd.org>
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/bus.h>
32 #include <sys/kernel.h>
33 #include <sys/lock.h>
34 #include <sys/mutex.h>
35 #include <sys/smp.h>
36
37 #include <vm/vm.h>
38 #include <vm/pmap.h>
39
40 #include <machine/cpu.h>
41 #include <machine/smp.h>
42 #include <machine/fdt.h>
43 #include <machine/intr.h>
44 #include <machine/platform.h>
45 #include <machine/platformvar.h>
46
47 #include <arm/freescale/imx/imx6_machdep.h>
48
49 #define SCU_PHYSBASE 0x00a00000
50 #define SCU_SIZE 0x00001000
51
52 #define SCU_CONTROL_REG 0x00
53 #define SCU_CONTROL_ENABLE (1 << 0)
54 #define SCU_CONFIG_REG 0x04
55 #define SCU_CONFIG_REG_NCPU_MASK 0x03
56 #define SCU_CPUPOWER_REG 0x08
57 #define SCU_INV_TAGS_REG 0x0c
58 #define SCU_DIAG_CONTROL 0x30
59 #define SCU_DIAG_DISABLE_MIGBIT (1 << 0)
60 #define SCU_FILTER_START_REG 0x40
61 #define SCU_FILTER_END_REG 0x44
62 #define SCU_SECURE_ACCESS_REG 0x50
63 #define SCU_NONSECURE_ACCESS_REG 0x54
64
65 #define SRC_PHYSBASE 0x020d8000
66 #define SRC_SIZE 0x4000
67 #define SRC_CONTROL_REG 0x00
68 #define SRC_CONTROL_C1ENA_SHIFT 22 /* Bit for Core 1 enable */
69 #define SRC_CONTROL_C1RST_SHIFT 14 /* Bit for Core 1 reset */
70 #define SRC_GPR0_C1FUNC 0x20 /* Register for Core 1 entry func */
71 #define SRC_GPR1_C1ARG 0x24 /* Register for Core 1 entry arg */
72
73 void
imx6_mp_setmaxid(platform_t plat)74 imx6_mp_setmaxid(platform_t plat)
75 {
76 bus_space_handle_t scu;
77 int hwcpu, ncpu;
78 uint32_t val;
79
80 /* If we've already set the global vars don't bother to do it again. */
81 if (mp_ncpus != 0)
82 return;
83
84 if (bus_space_map(fdtbus_bs_tag, SCU_PHYSBASE, SCU_SIZE, 0, &scu) != 0)
85 panic("Couldn't map the SCU\n");
86 val = bus_space_read_4(fdtbus_bs_tag, scu, SCU_CONFIG_REG);
87 hwcpu = (val & SCU_CONFIG_REG_NCPU_MASK) + 1;
88 bus_space_unmap(fdtbus_bs_tag, scu, SCU_SIZE);
89
90 ncpu = hwcpu;
91 TUNABLE_INT_FETCH("hw.ncpu", &ncpu);
92 if (ncpu < 1 || ncpu > hwcpu)
93 ncpu = hwcpu;
94
95 mp_ncpus = ncpu;
96 mp_maxid = ncpu - 1;
97 }
98
99 void
imx6_mp_start_ap(platform_t plat)100 imx6_mp_start_ap(platform_t plat)
101 {
102 bus_space_handle_t scu;
103 bus_space_handle_t src;
104
105 uint32_t val;
106 int i;
107
108 if (bus_space_map(fdtbus_bs_tag, SCU_PHYSBASE, SCU_SIZE, 0, &scu) != 0)
109 panic("Couldn't map the SCU\n");
110 if (bus_space_map(fdtbus_bs_tag, SRC_PHYSBASE, SRC_SIZE, 0, &src) != 0)
111 panic("Couldn't map the system reset controller (SRC)\n");
112
113 /*
114 * Invalidate SCU cache tags. The 0x0000ffff constant invalidates all
115 * ways on all cores 0-3. Per the ARM docs, it's harmless to write to
116 * the bits for cores that are not present.
117 */
118 bus_space_write_4(fdtbus_bs_tag, scu, SCU_INV_TAGS_REG, 0x0000ffff);
119
120 /*
121 * Erratum ARM/MP: 764369 (problems with cache maintenance).
122 * Setting the "disable-migratory bit" in the undocumented SCU
123 * Diagnostic Control Register helps work around the problem.
124 */
125 val = bus_space_read_4(fdtbus_bs_tag, scu, SCU_DIAG_CONTROL);
126 bus_space_write_4(fdtbus_bs_tag, scu, SCU_DIAG_CONTROL,
127 val | SCU_DIAG_DISABLE_MIGBIT);
128
129 /*
130 * Enable the SCU, then clean the cache on this core. After these two
131 * operations the cache tag ram in the SCU is coherent with the contents
132 * of the cache on this core. The other cores aren't running yet so
133 * their caches can't contain valid data yet, but we've initialized
134 * their SCU tag ram above, so they will be coherent from startup.
135 */
136 val = bus_space_read_4(fdtbus_bs_tag, scu, SCU_CONTROL_REG);
137 bus_space_write_4(fdtbus_bs_tag, scu, SCU_CONTROL_REG,
138 val | SCU_CONTROL_ENABLE);
139 dcache_wbinv_poc_all();
140
141 /*
142 * For each AP core, set the entry point address and argument registers,
143 * and set the core-enable and core-reset bits in the control register.
144 */
145 val = bus_space_read_4(fdtbus_bs_tag, src, SRC_CONTROL_REG);
146 for (i=1; i < mp_ncpus; i++) {
147 bus_space_write_4(fdtbus_bs_tag, src, SRC_GPR0_C1FUNC + 8*i,
148 pmap_kextract((vm_offset_t)mpentry));
149 bus_space_write_4(fdtbus_bs_tag, src, SRC_GPR1_C1ARG + 8*i, 0);
150
151 val |= ((1 << (SRC_CONTROL_C1ENA_SHIFT - 1 + i )) |
152 ( 1 << (SRC_CONTROL_C1RST_SHIFT - 1 + i)));
153 }
154 bus_space_write_4(fdtbus_bs_tag, src, SRC_CONTROL_REG, val);
155
156 dsb();
157 sev();
158
159 bus_space_unmap(fdtbus_bs_tag, scu, SCU_SIZE);
160 bus_space_unmap(fdtbus_bs_tag, src, SRC_SIZE);
161 }
162