xref: /freebsd/sys/arm/mv/armada38x/armada38x_mp.c (revision 95ee2897e98f5d444f26ed2334cc7c439f9c16c6)
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 #include <machine/platformvar.h>
39 
40 #include <dev/ofw/ofw_bus.h>
41 #include <dev/ofw/ofw_bus_subr.h>
42 
43 #include <arm/mv/mvreg.h>
44 
45 #include "pmsu.h"
46 
47 static int cpu_reset_deassert(void);
48 void mv_a38x_platform_mp_setmaxid(platform_t plate);
49 void mv_a38x_platform_mp_start_ap(platform_t plate);
50 
51 static int
52 cpu_reset_deassert(void)
53 {
54 	bus_space_handle_t vaddr;
55 	uint32_t reg;
56 	int rv;
57 
58 	rv = bus_space_map(fdtbus_bs_tag, (bus_addr_t)MV_CPU_RESET_BASE,
59 	    MV_CPU_RESET_REGS_LEN, 0, &vaddr);
60 	if (rv != 0)
61 		return (rv);
62 
63 	/* CPU1 is held at reset by default - clear assert bit to release it */
64 	reg = bus_space_read_4(fdtbus_bs_tag, vaddr, CPU_RESET_OFFSET(1));
65 	reg &= ~CPU_RESET_ASSERT;
66 
67 	bus_space_write_4(fdtbus_bs_tag, vaddr, CPU_RESET_OFFSET(1), reg);
68 
69 	bus_space_unmap(fdtbus_bs_tag, vaddr, MV_CPU_RESET_REGS_LEN);
70 
71 	return (0);
72 }
73 
74 static int
75 platform_cnt_cpus(void)
76 {
77 	bus_space_handle_t vaddr_scu;
78 	phandle_t cpus_node, child;
79 	char device_type[16];
80 	int fdt_cpu_count = 0;
81 	int reg_cpu_count = 0;
82 	uint32_t val;
83 	int rv;
84 
85 	cpus_node = OF_finddevice("/cpus");
86 	if (cpus_node == -1) {
87 		/* Default is one core */
88 		mp_ncpus = 1;
89 		return (0);
90 	}
91 
92 	/* Get number of 'cpu' nodes from FDT */
93 	for (child = OF_child(cpus_node); child != 0; child = OF_peer(child)) {
94 		/* Check if child is a CPU */
95 		memset(device_type, 0, sizeof(device_type));
96 		rv = OF_getprop(child, "device_type", device_type,
97 		    sizeof(device_type) - 1);
98 		if (rv < 0)
99 			continue;
100 		if (strcmp(device_type, "cpu") != 0)
101 			continue;
102 
103 		fdt_cpu_count++;
104 	}
105 
106 	/* Get number of CPU cores from SCU register to cross-check with FDT */
107 	rv = bus_space_map(fdtbus_bs_tag, (bus_addr_t)MV_SCU_BASE,
108 	    MV_SCU_REGS_LEN, 0, &vaddr_scu);
109 	if (rv != 0) {
110 		/* Default is one core */
111 		mp_ncpus = 1;
112 		return (0);
113 	}
114 
115 	val = bus_space_read_4(fdtbus_bs_tag, vaddr_scu, MV_SCU_REG_CONFIG);
116 	bus_space_unmap(fdtbus_bs_tag, vaddr_scu, MV_SCU_REGS_LEN);
117         reg_cpu_count = (val & SCU_CFG_REG_NCPU_MASK) + 1;
118 
119 	/* Set mp_ncpus to number of cpus in FDT unless SOC contains only one */
120 	mp_ncpus = min(reg_cpu_count, fdt_cpu_count);
121 	/* mp_ncpus must be at least 1 */
122 	mp_ncpus = max(1, mp_ncpus);
123 
124 	return (mp_ncpus);
125 }
126 
127 void
128 mv_a38x_platform_mp_setmaxid(platform_t plate)
129 {
130 
131 	/* Armada38x family supports maximum 2 cores */
132 	mp_ncpus = platform_cnt_cpus();
133 	mp_maxid = mp_ncpus - 1;
134 }
135 
136 void
137 mv_a38x_platform_mp_start_ap(platform_t plate)
138 {
139 	int rv;
140 
141 	/* Write secondary entry address to PMSU register */
142 	rv = pmsu_boot_secondary_cpu();
143 	if (rv != 0)
144 		return;
145 
146 	/* Release CPU1 from reset */
147 	cpu_reset_deassert();
148 }
149