xref: /netbsd-src/sys/arch/evbmips/sbmips/cpu.c (revision aa3d1fe6ec3c7d927c11c03446382b1565528338)
1 /* $NetBSD: cpu.c,v 1.4 2023/12/05 19:16:48 andvar Exp $ */
2 
3 /*
4  * Copyright 2000, 2001
5  * Broadcom Corporation. All rights reserved.
6  *
7  * This software is furnished under license and may be used and copied only
8  * in accordance with the following terms and conditions.  Subject to these
9  * conditions, you may download, copy, install, use, modify and distribute
10  * modified or unmodified copies of this software in source and/or binary
11  * form. No title or ownership is transferred hereby.
12  *
13  * 1) Any source code used, modified or distributed must reproduce and
14  *    retain this copyright notice and list of conditions as they appear in
15  *    the source file.
16  *
17  * 2) No right is granted to use any trade name, trademark, or logo of
18  *    Broadcom Corporation.  The "Broadcom Corporation" name may not be
19  *    used to endorse or promote products derived from this software
20  *    without the prior written permission of Broadcom Corporation.
21  *
22  * 3) THIS SOFTWARE IS PROVIDED "AS-IS" AND ANY EXPRESS OR IMPLIED
23  *    WARRANTIES, INCLUDING BUT NOT LIMITED TO, ANY IMPLIED WARRANTIES OF
24  *    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR
25  *    NON-INFRINGEMENT ARE DISCLAIMED. IN NO EVENT SHALL BROADCOM BE LIABLE
26  *    FOR ANY DAMAGES WHATSOEVER, AND IN PARTICULAR, BROADCOM SHALL NOT BE
27  *    LIABLE FOR DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
28  *    CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29  *    SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
30  *    BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
31  *    WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
32  *    OR OTHERWISE), EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 #include <sys/cdefs.h>
36 __KERNEL_RCSID(0, "$NetBSD: cpu.c,v 1.4 2023/12/05 19:16:48 andvar Exp $");
37 
38 #include "opt_multiprocessor.h"
39 
40 #include <sys/param.h>
41 #include <sys/cpu.h>
42 #include <sys/device.h>
43 #include <sys/kernel.h>
44 #include <sys/systm.h>
45 
46 #include <mips/locore.h>
47 #include <mips/cache.h>
48 
49 #include <evbmips/sbmips/cpuvar.h>
50 #include <evbmips/sbmips/systemsw.h>
51 
52 #include <mips/sibyte/include/zbbusvar.h>
53 #include <mips/sibyte/include/sb1250_regs.h>
54 #include <mips/sibyte/include/sb1250_scd.h>
55 #include <mips/sibyte/dev/sbscdvar.h>
56 #include <mips/cfe/cfe_api.h>
57 
58 #define	READ_REG(rp)		mips3_ld((register_t)(rp))
59 
60 static int	cpu_match(device_t, cfdata_t, void *);
61 static void	cpu_attach(device_t, device_t, void *);
62 
63 CFATTACH_DECL_NEW(cpu, sizeof(struct cpu_softc),
64     cpu_match, cpu_attach, NULL, NULL);
65 
66 static u_int found = 0;
67 
68 static int
cpu_match(device_t parent,cfdata_t match,void * aux)69 cpu_match(device_t parent, cfdata_t match, void *aux)
70 {
71 	struct zbbus_attach_args *zap = aux;
72 	int part;
73 
74 	if (zap->za_locs.za_type != ZBBUS_ENTTYPE_CPU)
75 		return (0);
76 
77 	/*
78 	 * The 3rd hex digit of the part number is the number of CPUs;
79 	 * ref Table 26, p38 1250-UM101-R.
80 	 */
81 	part = G_SYS_PART(READ_REG(MIPS_PHYS_TO_KSEG1(A_SCD_SYSTEM_REVISION)));
82 	return (found < ((part >> 8) & 0xf));
83 }
84 
85 static void
cpu_attach(device_t parent,device_t self,void * aux)86 cpu_attach(device_t parent, device_t self, void *aux)
87 {
88 	struct cpu_info *ci;
89 	struct cpu_softc * const cpu = device_private(self);
90 	const char * const xname = device_xname(self);
91 	uint32_t config;
92 	int plldiv;
93 
94 	found++;
95 
96 	/* XXX this code must run on the target CPU */
97 	config = mips3_cp0_config_read();
98 	__USE(config);
99 	KASSERT((config & MIPS3_CONFIG_K0_MASK) == 5);
100 
101 	/* Determine CPU frequency */
102 
103 	/* XXX:  We should determine the CPU frequency from a time source
104 	 *       not coupled with the CPU crystal, like the RTC.  Unfortunately
105 	 *       we don't attach that yet...
106 	 */
107 	plldiv = G_SYS_PLL_DIV(READ_REG(MIPS_PHYS_TO_KSEG1(A_SCD_SYSTEM_CFG)));
108 	if (plldiv == 0) {
109 		aprint_normal(": PLL_DIV of zero found, assuming 6 (300MHz)\n");
110 		plldiv = 6;
111 
112 		aprint_normal("%s", xname);
113 	}
114 
115 	if (found == 1) {
116 		ci = curcpu();
117 		ci->ci_cpu_freq = 50000000 * plldiv;
118 		/* Compute the delay divisor. */
119 		ci->ci_divisor_delay = (ci->ci_cpu_freq + 500000) / 1000000;
120 		/* Compute clock cycles per hz */
121 		ci->ci_cycles_per_hz = (ci->ci_cpu_freq + hz / 2 ) / hz;
122 
123 		aprint_normal(": %lu.%02luMHz (hz cycles = %lu, delay divisor = %lu)\n",
124 		    ci->ci_cpu_freq / 1000000,
125 		    (ci->ci_cpu_freq % 1000000) / 10000,
126 		    ci->ci_cycles_per_hz, ci->ci_divisor_delay);
127 
128 		KASSERT(ci->ci_cpuid == 0);
129 
130 		cpu->sb1cpu_dev = self;
131 		cpu->sb1cpu_ci = ci;
132 		ci->ci_softc = cpu;
133 
134 		sb1250_cpu_init(cpu);
135 	} else {
136 #if defined(MULTIPROCESSOR)
137 		int status;
138 		ci = cpu_info_alloc(NULL, found - 1, 0, found - 1, 0);
139 		KASSERT(ci);
140 
141 		cpu->sb1cpu_dev = self;
142 		cpu->sb1cpu_ci = ci;
143 		ci->ci_softc = cpu;
144 
145 		sb1250_cpu_init(cpu);
146 
147 		status = cfe_cpu_start(ci->ci_cpuid, cpu_trampoline,
148 		    (long) ci->ci_data.cpu_idlelwp->l_md.md_utf, 0,
149 		    (long) ci);
150 		if (status != 0) {
151 			aprint_error(": CFE call to start failed: %d\n",
152 			    status);
153 		}
154 		for (size_t i = 0; i < 10000; i++) {
155 			if (kcpuset_isset(cpus_hatched, cpu_index(ci)))
156 				 break;
157 			DELAY(100);
158 		}
159 		if (!kcpuset_isset(cpus_hatched, cpu_index(ci))) {
160 			aprint_error(": failed to hatch!\n");
161 			return;
162 		}
163 #else
164 		aprint_normal("\n");
165 		aprint_normal_dev(self,
166 		    "processor off-line; "
167 		    "multiprocessor support not present in kernel\n");
168 		return;
169 #endif
170 	}
171 
172 	/*
173 	 * Announce ourselves.
174 	 */
175 	aprint_normal("%s: ", xname);
176 	cpu_identify(self);
177 
178 	cpu_attach_common(self, ci);
179 }
180