1 /*- 2 * Copyright (c) 2011 Nathan Whitehorn 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include <sys/param.h> 31 #include <sys/kernel.h> 32 #include <sys/lock.h> 33 #include <sys/mutex.h> 34 #include <sys/systm.h> 35 #include <sys/proc.h> 36 37 #include <vm/vm.h> 38 #include <vm/vm_page.h> 39 #include <vm/pmap.h> 40 41 #include <machine/bus.h> 42 #include <machine/md_var.h> 43 #include <machine/pcb.h> 44 #include <machine/pmap.h> 45 #include <machine/rtas.h> 46 #include <machine/stdarg.h> 47 48 #include <dev/ofw/openfirm.h> 49 50 static MALLOC_DEFINE(M_RTAS, "rtas", "Run Time Abstraction Service"); 51 52 static vm_offset_t rtas_bounce_phys; 53 static caddr_t rtas_bounce_virt; 54 static off_t rtas_bounce_offset; 55 static size_t rtas_bounce_size; 56 static uintptr_t rtas_private_data; 57 static struct mtx rtas_mtx; 58 static phandle_t rtas; 59 60 /* From ofwcall.S */ 61 int rtascall(vm_offset_t callbuffer, uintptr_t rtas_privdat); 62 extern uintptr_t rtas_entry; 63 extern register_t rtasmsr; 64 65 int setfault(faultbuf); /* defined in locore.S */ 66 67 /* 68 * After the VM is up, allocate RTAS memory and instantiate it 69 */ 70 71 static void rtas_setup(void *); 72 73 SYSINIT(rtas_setup, SI_SUB_KMEM, SI_ORDER_ANY, rtas_setup, NULL); 74 75 static void 76 rtas_setup(void *junk) 77 { 78 ihandle_t rtasi; 79 cell_t rtas_size = 0, rtas_ptr; 80 char path[31]; 81 int result; 82 83 rtas = OF_finddevice("/rtas"); 84 if (rtas == -1) { 85 rtas = 0; 86 return; 87 } 88 OF_package_to_path(rtas, path, sizeof(path)); 89 rtasi = OF_open(path); 90 if (rtasi == 0) { 91 rtas = 0; 92 printf("Error initializing RTAS: could not open node\n"); 93 return; 94 } 95 96 mtx_init(&rtas_mtx, "RTAS", MTX_DEF, 0); 97 98 /* RTAS must be called with everything turned off in MSR */ 99 rtasmsr = mfmsr(); 100 rtasmsr &= ~(PSL_IR | PSL_DR | PSL_EE | PSL_SE); 101 #ifdef __powerpc64__ 102 rtasmsr &= ~PSL_SF; 103 #endif 104 105 /* 106 * Allocate rtas_size + one page of contiguous, wired physical memory 107 * that can fit into a 32-bit address space and accessed from real mode. 108 * This is used both to bounce arguments and for RTAS private data. 109 * 110 * It must be 4KB-aligned and not cross a 256 MB boundary. 111 */ 112 113 OF_getprop(rtas, "rtas-size", &rtas_size, sizeof(rtas_size)); 114 rtas_size = round_page(rtas_size); 115 rtas_bounce_virt = contigmalloc(rtas_size + PAGE_SIZE, M_RTAS, 0, 0, 116 ulmin(platform_real_maxaddr(), BUS_SPACE_MAXADDR_32BIT), 117 4096, 256*1024*1024); 118 119 rtas_private_data = vtophys(rtas_bounce_virt); 120 rtas_bounce_virt += rtas_size; /* Actual bounce area */ 121 rtas_bounce_phys = vtophys(rtas_bounce_virt); 122 rtas_bounce_size = PAGE_SIZE; 123 124 /* 125 * Instantiate RTAS. We always use the 32-bit version. 126 */ 127 128 result = OF_call_method("instantiate-rtas", rtasi, 1, 1, 129 (cell_t)rtas_private_data, &rtas_ptr); 130 OF_close(rtasi); 131 132 if (result != 0) { 133 rtas = 0; 134 rtas_ptr = 0; 135 printf("Error initializing RTAS (%d)\n", result); 136 return; 137 } 138 139 rtas_entry = (uintptr_t)(rtas_ptr); 140 } 141 142 static cell_t 143 rtas_real_map(const void *buf, size_t len) 144 { 145 cell_t phys; 146 147 mtx_assert(&rtas_mtx, MA_OWNED); 148 149 /* 150 * Make sure the bounce page offset satisfies any reasonable 151 * alignment constraint. 152 */ 153 rtas_bounce_offset += sizeof(register_t) - 154 (rtas_bounce_offset % sizeof(register_t)); 155 156 if (rtas_bounce_offset + len > rtas_bounce_size) { 157 panic("Oversize RTAS call!"); 158 return 0; 159 } 160 161 if (buf != NULL) 162 memcpy(rtas_bounce_virt + rtas_bounce_offset, buf, len); 163 else 164 return (0); 165 166 phys = rtas_bounce_phys + rtas_bounce_offset; 167 rtas_bounce_offset += len; 168 169 return (phys); 170 } 171 172 static void 173 rtas_real_unmap(cell_t physaddr, void *buf, size_t len) 174 { 175 mtx_assert(&rtas_mtx, MA_OWNED); 176 177 if (physaddr == 0) 178 return; 179 180 memcpy(buf, rtas_bounce_virt + (physaddr - rtas_bounce_phys), len); 181 } 182 183 /* Check if we have RTAS */ 184 int 185 rtas_exists(void) 186 { 187 return (rtas != 0); 188 } 189 190 /* Call an RTAS method by token */ 191 int 192 rtas_call_method(cell_t token, int nargs, int nreturns, ...) 193 { 194 vm_offset_t argsptr; 195 faultbuf env; 196 va_list ap; 197 struct { 198 cell_t token; 199 cell_t nargs; 200 cell_t nreturns; 201 cell_t args_n_results[12]; 202 } args; 203 int n, result; 204 205 if (!rtas_exists() || nargs + nreturns > 12) 206 return (-1); 207 208 args.token = token; 209 va_start(ap, nreturns); 210 211 mtx_lock(&rtas_mtx); 212 rtas_bounce_offset = 0; 213 214 args.nargs = nargs; 215 args.nreturns = nreturns; 216 217 for (n = 0; n < nargs; n++) 218 args.args_n_results[n] = va_arg(ap, cell_t); 219 220 argsptr = rtas_real_map(&args, sizeof(args)); 221 222 /* Get rid of any stale machine checks that have been waiting. */ 223 __asm __volatile ("sync; isync"); 224 if (!setfault(env)) { 225 __asm __volatile ("sync"); 226 result = rtascall(argsptr, rtas_private_data); 227 __asm __volatile ("sync; isync"); 228 } else { 229 result = RTAS_HW_ERROR; 230 } 231 curthread->td_pcb->pcb_onfault = 0; 232 __asm __volatile ("sync"); 233 234 rtas_real_unmap(argsptr, &args, sizeof(args)); 235 mtx_unlock(&rtas_mtx); 236 237 if (result < 0) 238 return (result); 239 240 for (n = nargs; n < nargs + nreturns; n++) 241 *va_arg(ap, cell_t *) = args.args_n_results[n]; 242 return (result); 243 } 244 245 /* Look up an RTAS token */ 246 cell_t 247 rtas_token_lookup(const char *method) 248 { 249 cell_t token; 250 251 if (!rtas_exists()) 252 return (-1); 253 254 if (OF_getprop(rtas, method, &token, sizeof(token)) == -1) 255 return (-1); 256 257 return (token); 258 } 259 260 261