1 /* $NetBSD: cpus.c,v 1.7 2023/05/07 12:41:49 skrll Exp $ */ 2 3 /*- 4 * Copyright (c) 2017 Jared McNeill <jmcneill@invisible.ca> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __KERNEL_RCSID(0, "$NetBSD: cpus.c,v 1.7 2023/05/07 12:41:49 skrll Exp $"); 31 32 #include <sys/param.h> 33 #include <sys/bus.h> 34 #include <sys/device.h> 35 #include <sys/intr.h> 36 #include <sys/systm.h> 37 #include <sys/kernel.h> 38 #include <sys/kmem.h> 39 40 #include <dev/fdt/fdtvar.h> 41 42 #ifdef __riscv 43 #include <machine/machdep.h> 44 #endif 45 46 static int cpus_match(device_t, cfdata_t, void *); 47 static void cpus_attach(device_t, device_t, void *); 48 49 static bool cpus_cpu_enabled(int); 50 51 CFATTACH_DECL_NEW(cpus, 0, cpus_match, cpus_attach, NULL, NULL); 52 53 static int 54 cpus_match(device_t parent, cfdata_t cf, void *aux) 55 { 56 struct fdt_attach_args * const faa = aux; 57 58 return OF_finddevice("/cpus") == faa->faa_phandle; 59 } 60 61 static void 62 cpus_attach(device_t parent, device_t self, void *aux) 63 { 64 struct fdt_attach_args * const faa = aux; 65 const int phandle = faa->faa_phandle; 66 int child; 67 68 aprint_naive("\n"); 69 aprint_normal("\n"); 70 71 #ifdef __riscv 72 cpus_fdt_md_attach(parent, self, faa); 73 #endif 74 for (child = OF_child(phandle); child; child = OF_peer(child)) { 75 if (!cpus_cpu_enabled(child)) 76 continue; 77 fdt_add_child(self, child, faa, 0); 78 } 79 } 80 81 static bool 82 cpus_cpu_enabled(int child) 83 { 84 const char *s; 85 86 /* Only match nodes with device_type = "cpu" */ 87 s = fdtbus_get_string(child, "device_type"); 88 if (!s || strcmp(s, "cpu") != 0) 89 return false; 90 91 /* If status is set, it must be either "okay" or "disabled" */ 92 s = fdtbus_get_string(child, "status"); 93 if (s) { 94 if (strcmp(s, "okay") == 0) 95 return true; 96 if (strcmp(s, "disabled") == 0) 97 return of_hasprop(child, "enable-method"); 98 return false; 99 } else { 100 return true; 101 } 102 } 103