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cpu.c revision 1.6
      1 /*	$NetBSD: cpu.c,v 1.6 2024/04/07 22:52:53 riastradh Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 2023 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Nick Hudson
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 #include "opt_multiprocessor.h"
     33 
     34 #include <sys/cdefs.h>
     35 __KERNEL_RCSID(0, "$NetBSD: cpu.c,v 1.6 2024/04/07 22:52:53 riastradh Exp $");
     36 
     37 #include <sys/param.h>
     38 
     39 #include <sys/cpu.h>
     40 #include <sys/device.h>
     41 #include <sys/kmem.h>
     42 #include <sys/reboot.h>
     43 #include <sys/sysctl.h>
     44 
     45 #include <riscv/cpu.h>
     46 #include <riscv/cpuvar.h>
     47 #include <riscv/machdep.h>
     48 #include <riscv/sbi.h>
     49 
     50 #ifdef MULTIPROCESSOR
     51 #define NCPUINFO	MAXCPUS
     52 #else
     53 #define NCPUINFO	1
     54 #endif /* MULTIPROCESSOR */
     55 
     56 static void
     57 cache_nullop(vaddr_t va, paddr_t pa, psize_t sz)
     58 {
     59 }
     60 
     61 void (*cpu_sdcache_wbinv_range)(vaddr_t, paddr_t, psize_t) = cache_nullop;
     62 void (*cpu_sdcache_inv_range)(vaddr_t, paddr_t, psize_t) = cache_nullop;
     63 void (*cpu_sdcache_wb_range)(vaddr_t, paddr_t, psize_t) = cache_nullop;
     64 
     65 u_int   riscv_dcache_align = CACHE_LINE_SIZE;
     66 u_int   riscv_dcache_align_mask = CACHE_LINE_SIZE - 1;
     67 
     68 #define CPU_VENDOR_SIFIVE	0x489
     69 
     70 #define CPU_ARCH_7SERIES	0x8000000000000007
     71 
     72 struct cpu_arch {
     73 	uint64_t	 ca_id;
     74 	const char	*ca_name;
     75 };
     76 
     77 struct cpu_arch cpu_arch_sifive[] = {
     78     {
     79 	.ca_id = CPU_ARCH_7SERIES,
     80 	.ca_name = "7-Series Processor (E7, S7, U7 series)",
     81     },
     82     { },	// terminator
     83 };
     84 
     85 struct cpu_vendor {
     86 	uint32_t	 	 cv_id;
     87 	const char		*cv_name;
     88 	struct cpu_arch		*cv_arch;
     89 } cpu_vendors[] = {
     90     {
     91 	.cv_id = CPU_VENDOR_SIFIVE,
     92 	.cv_name = "SiFive",
     93 	.cv_arch = cpu_arch_sifive,
     94     },
     95 };
     96 
     97 /*
     98  * Our exported cpu_info structs; indexed by BP as 0 and APs [1, ncpu - 1]
     99  */
    100 struct cpu_info cpu_info_store[NCPUINFO] = {
    101 	[0] = {
    102 		.ci_cpl = IPL_HIGH,
    103 		.ci_curlwp = &lwp0,
    104 		.ci_tlb_info = &pmap_tlb0_info,
    105 #ifdef MULTIPROCESSOR
    106 		.ci_flags = CPUF_PRIMARY | CPUF_PRESENT | CPUF_RUNNING,
    107 #endif
    108 	}
    109 };
    110 
    111 /*
    112  * setup the per-cpu sysctl tree.
    113  */
    114 static void
    115 cpu_setup_sysctl(device_t dv, struct cpu_info *ci)
    116 {
    117 	const struct sysctlnode *cpunode = NULL;
    118 
    119 	sysctl_createv(NULL, 0, NULL, &cpunode,
    120 		       CTLFLAG_PERMANENT,
    121 		       CTLTYPE_NODE, device_xname(dv), NULL,
    122 		       NULL, 0, NULL, 0,
    123 		       CTL_MACHDEP,
    124 		       CTL_CREATE, CTL_EOL);
    125 
    126 	if (cpunode == NULL)
    127 		return;
    128 }
    129 
    130 
    131 static void
    132 cpu_identify(device_t self, struct cpu_info *ci)
    133 {
    134 	const register_t mvendorid = sbi_get_mvendorid().value;
    135 	const register_t marchid = sbi_get_marchid().value;
    136 	const uint32_t mimpid = sbi_get_mimpid().value;
    137 	struct cpu_arch *cv_arch = NULL;
    138 	const char *cv_name = NULL;
    139 	const char *ca_name = NULL;
    140 	char vendor[128];
    141 	char arch[128];
    142 
    143 	for (size_t i = 0; i < __arraycount(cpu_vendors); i++) {
    144 		if (mvendorid == cpu_vendors[i].cv_id) {
    145 			cv_name = cpu_vendors[i].cv_name;
    146 			cv_arch = cpu_vendors[i].cv_arch;
    147 			break;
    148 		}
    149 	}
    150 
    151 	if (cv_arch != NULL) {
    152 		for (size_t i = 0; cv_arch[i].ca_name != NULL; i++) {
    153 			if (marchid == cv_arch[i].ca_id) {
    154 				ca_name = cv_arch[i].ca_name;
    155 				break;
    156 			}
    157 		}
    158 	}
    159 
    160 	if (cv_name == NULL) {
    161 		snprintf(vendor, sizeof(vendor), "vendor %" PRIxREGISTER, mvendorid);
    162 		cv_name = vendor;
    163 	}
    164 	if (ca_name == NULL) {
    165 		snprintf(arch, sizeof(arch), "arch %" PRIxREGISTER, marchid);
    166 		ca_name = arch;
    167 	}
    168 
    169 	aprint_naive("\n");
    170 	aprint_normal(": %s %s imp. %" PRIx32 "\n", cv_name, ca_name, mimpid);
    171         aprint_verbose_dev(ci->ci_dev,
    172 	    "vendor 0x%" PRIxREGISTER " arch. %" PRIxREGISTER " imp. %" PRIx32 "\n",
    173 	    mvendorid, marchid, mimpid);
    174 }
    175 
    176 
    177 void
    178 cpu_attach(device_t dv, cpuid_t hartid)
    179 {
    180 	struct cpu_info *ci;
    181 
    182 	/* Check for the BP */
    183 	if (hartid == cpu_bphartid) {
    184 		ci = curcpu();
    185 		KASSERTMSG(ci == &cpu_info_store[0], "ci %p", ci);
    186 		ci->ci_cpuid = hartid;
    187 		ci->ci_cpu_freq = riscv_timer_frequency_get();
    188 	} else {
    189 #ifdef MULTIPROCESSOR
    190 		if ((boothowto & RB_MD1) != 0) {
    191 			aprint_naive("\n");
    192 			aprint_normal(": multiprocessor boot disabled\n");
    193 			return;
    194 		}
    195 
    196 		KASSERT(hartid < MAXCPUS);
    197 		KASSERT(cpu_hartindex[hartid] < MAXCPUS);
    198 
    199 		ci = &cpu_info_store[cpu_hartindex[hartid]];
    200 
    201 		ci->ci_cpl = IPL_HIGH;
    202 		ci->ci_cpuid = hartid;
    203 
    204 		if (!cpu_hatched_p(cpu_hartindex[hartid])) {
    205 			ci->ci_dev = dv;
    206 			device_set_private(dv, ci);
    207 			ci->ci_index = -1;
    208 
    209 			aprint_naive(": disabled\n");
    210 			aprint_normal(": disabled (unresponsive)\n");
    211 			return;
    212 		}
    213 #else /* MULTIPROCESSOR */
    214 		aprint_naive(": disabled\n");
    215 		aprint_normal(": disabled (uniprocessor kernel)\n");
    216 		return;
    217 #endif /* MULTIPROCESSOR */
    218 	}
    219 
    220 	ci->ci_dev = dv;
    221 	device_set_private(dv, ci);
    222 
    223 	cpu_identify(dv, ci);
    224 
    225 #ifdef MULTIPROCESSOR
    226 	kcpuset_create(&ci->ci_shootdowncpus, true);
    227 
    228 	ipi_init(ci);
    229 
    230 	kcpuset_create(&ci->ci_multicastcpus, true);
    231 	kcpuset_create(&ci->ci_watchcpus, true);
    232 	kcpuset_create(&ci->ci_ddbcpus, true);
    233 
    234 	if (hartid != cpu_bphartid) {
    235 		mi_cpu_attach(ci);
    236 	}
    237 #endif /* MULTIPROCESSOR */
    238 	cpu_setup_sysctl(dv, ci);
    239 }
    240 
    241 #ifdef MULTIPROCESSOR
    242 /*
    243  * Initialise a secondary processor.
    244  *
    245  * printf isn't available as kmutex(9) relies on curcpu which isn't setup yet.
    246  *
    247  */
    248 void __noasan
    249 cpu_init_secondary_processor(u_int cpuindex)
    250 {
    251 	cpu_set_hatched(cpuindex);
    252 
    253 	/*
    254 	 * return to assembly to wait for cpu_boot_secondary_processors
    255 	 */
    256 }
    257 
    258 
    259 /*
    260  * When we are called, the MMU and caches are on and we are running on the stack
    261  * of the idlelwp for this cpu.
    262  */
    263 void
    264 cpu_hatch(struct cpu_info *ci, unsigned long cpuindex)
    265 {
    266 	KASSERT(curcpu() == ci);
    267 
    268 	// Show this CPU as present.
    269 	atomic_or_ulong(&ci->ci_flags, CPUF_PRESENT);
    270 
    271 	ci->ci_cpu_freq = riscv_timer_frequency_get();
    272 
    273 	riscv_timer_init();
    274 
    275 	kcpuset_set(cpus_hatched, cpu_index(ci));
    276 	kcpuset_set(cpus_running, cpu_index(ci));
    277 
    278 	/*
    279 	 * clear my bit of the mailbox to tell cpu_boot_secondary_processors().
    280 	 * Consider that if there are cpu0, 1, 2, 3, and cpu2 is unresponsive,
    281 	 * ci_index for each would be cpu0=0, cpu1=1, cpu2=undef, cpu3=2.
    282 	 * therefore we have to use device_unit instead of ci_index for mbox.
    283 	 */
    284 
    285 	cpu_clr_mbox(cpuindex);
    286 }
    287 #endif /* MULTIPROCESSOR */
    288