xref: /freebsd/sys/arm/mv/armada38x/armada38x_mp.c (revision 0f7f3352c8bc463607912e2463d13e52d44a4cae)
1 /*-
2  * Copyright (c) 2015 Semihalf.
3  * Copyright (c) 2015 Stormshield.
4  * All rights reserved.
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 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/bus.h>
33 #include <sys/smp.h>
34 
35 #include <machine/smp.h>
36 #include <machine/fdt.h>
37 #include <machine/intr.h>
38 
39 #include <dev/ofw/ofw_bus.h>
40 #include <dev/ofw/ofw_bus_subr.h>
41 
42 #include <arm/mv/mvreg.h>
43 
44 #include "pmsu.h"
45 
46 int cpu_reset_deassert(void);
47 
48 int
49 cpu_reset_deassert(void)
50 {
51 	bus_space_handle_t vaddr;
52 	uint32_t reg;
53 	int rv;
54 
55 	rv = bus_space_map(fdtbus_bs_tag, (bus_addr_t)MV_CPU_RESET_BASE,
56 	    MV_CPU_RESET_REGS_LEN, 0, &vaddr);
57 	if (rv != 0)
58 		return (rv);
59 
60 	/* CPU1 is held at reset by default - clear assert bit to release it */
61 	reg = bus_space_read_4(fdtbus_bs_tag, vaddr, CPU_RESET_OFFSET(1));
62 	reg &= ~CPU_RESET_ASSERT;
63 
64 	bus_space_write_4(fdtbus_bs_tag, vaddr, CPU_RESET_OFFSET(1), reg);
65 
66 	bus_space_unmap(fdtbus_bs_tag, vaddr, MV_CPU_RESET_REGS_LEN);
67 
68 	return (0);
69 }
70 
71 static int
72 platform_cnt_cpus(void)
73 {
74 	bus_space_handle_t vaddr_scu;
75 	phandle_t cpus_node, child;
76 	char device_type[16];
77 	int fdt_cpu_count = 0;
78 	int reg_cpu_count = 0;
79 	uint32_t val;
80 	int rv;
81 
82 	cpus_node = OF_finddevice("/cpus");
83 	if (cpus_node == -1) {
84 		/* Default is one core */
85 		mp_ncpus = 1;
86 		return (0);
87 	}
88 
89 	/* Get number of 'cpu' nodes from FDT */
90 	for (child = OF_child(cpus_node); child != 0; child = OF_peer(child)) {
91 		/* Check if child is a CPU */
92 		memset(device_type, 0, sizeof(device_type));
93 		rv = OF_getprop(child, "device_type", device_type,
94 		    sizeof(device_type) - 1);
95 		if (rv < 0)
96 			continue;
97 		if (strcmp(device_type, "cpu") != 0)
98 			continue;
99 
100 		fdt_cpu_count++;
101 	}
102 
103 	/* Get number of CPU cores from SCU register to cross-check with FDT */
104 	rv = bus_space_map(fdtbus_bs_tag, (bus_addr_t)MV_SCU_BASE,
105 	    MV_SCU_REGS_LEN, 0, &vaddr_scu);
106 	if (rv != 0) {
107 		/* Default is one core */
108 		mp_ncpus = 1;
109 		return (0);
110 	}
111 
112 	val = bus_space_read_4(fdtbus_bs_tag, vaddr_scu, MV_SCU_REG_CONFIG);
113 	bus_space_unmap(fdtbus_bs_tag, vaddr_scu, MV_SCU_REGS_LEN);
114         reg_cpu_count = (val & SCU_CFG_REG_NCPU_MASK) + 1;
115 
116 	/* Set mp_ncpus to number of cpus in FDT unless SOC contains only one */
117 	mp_ncpus = min(reg_cpu_count, fdt_cpu_count);
118 	/* mp_ncpus must be at least 1 */
119 	mp_ncpus = max(1, mp_ncpus);
120 
121 	return (mp_ncpus);
122 }
123 
124 void
125 platform_mp_setmaxid(void)
126 {
127 
128 	/* Armada38x family supports maximum 2 cores */
129 	mp_ncpus = platform_cnt_cpus();
130 	mp_maxid = 1;
131 }
132 
133 void
134 platform_mp_start_ap(void)
135 {
136 	int rv;
137 
138 	/* Write secondary entry address to PMSU register */
139 	rv = pmsu_boot_secondary_cpu();
140 	if (rv != 0)
141 		return;
142 
143 	/* Release CPU1 from reset */
144 	cpu_reset_deassert();
145 }
146