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 90 mtx_init(&rtas_mtx, "RTAS", NULL, MTX_SPIN); 91 92 /* RTAS must be called with everything turned off in MSR */ 93 rtasmsr = mfmsr(); 94 rtasmsr &= ~(PSL_IR | PSL_DR | PSL_EE | PSL_SE); 95 #ifdef __powerpc64__ 96 rtasmsr &= ~PSL_SF; 97 #endif 98 99 /* 100 * Allocate rtas_size + one page of contiguous, wired physical memory 101 * that can fit into a 32-bit address space and accessed from real mode. 102 * This is used both to bounce arguments and for RTAS private data. 103 * 104 * It must be 4KB-aligned and not cross a 256 MB boundary. 105 */ 106 107 OF_getencprop(rtas, "rtas-size", &rtas_size, sizeof(rtas_size)); 108 rtas_size = round_page(rtas_size); 109 rtas_bounce_virt = contigmalloc(rtas_size + PAGE_SIZE, M_RTAS, 0, 0, 110 ulmin(platform_real_maxaddr(), BUS_SPACE_MAXADDR_32BIT), 111 4096, 256*1024*1024); 112 113 rtas_private_data = vtophys(rtas_bounce_virt); 114 rtas_bounce_virt += rtas_size; /* Actual bounce area */ 115 rtas_bounce_phys = vtophys(rtas_bounce_virt); 116 rtas_bounce_size = PAGE_SIZE; 117 118 /* 119 * Instantiate RTAS. We always use the 32-bit version. 120 */ 121 122 if (OF_hasprop(rtas, "linux,rtas-entry") && 123 OF_hasprop(rtas, "linux,rtas-base")) { 124 OF_getencprop(rtas, "linux,rtas-base", &rtas_ptr, 125 sizeof(rtas_ptr)); 126 rtas_private_data = rtas_ptr; 127 OF_getencprop(rtas, "linux,rtas-entry", &rtas_ptr, 128 sizeof(rtas_ptr)); 129 } else { 130 rtasi = OF_open(path); 131 if (rtasi == 0) { 132 rtas = 0; 133 printf("Error initializing RTAS: could not open " 134 "node\n"); 135 return; 136 } 137 138 result = OF_call_method("instantiate-rtas", rtasi, 1, 1, 139 (cell_t)rtas_private_data, &rtas_ptr); 140 OF_close(rtasi); 141 142 if (result != 0) { 143 rtas = 0; 144 rtas_ptr = 0; 145 printf("Error initializing RTAS (%d)\n", result); 146 return; 147 } 148 } 149 150 rtas_entry = (uintptr_t)(rtas_ptr); 151 } 152 153 static cell_t 154 rtas_real_map(const void *buf, size_t len) 155 { 156 cell_t phys; 157 158 mtx_assert(&rtas_mtx, MA_OWNED); 159 160 /* 161 * Make sure the bounce page offset satisfies any reasonable 162 * alignment constraint. 163 */ 164 rtas_bounce_offset += sizeof(register_t) - 165 (rtas_bounce_offset % sizeof(register_t)); 166 167 if (rtas_bounce_offset + len > rtas_bounce_size) { 168 panic("Oversize RTAS call!"); 169 return 0; 170 } 171 172 if (buf != NULL) 173 memcpy(rtas_bounce_virt + rtas_bounce_offset, buf, len); 174 else 175 return (0); 176 177 phys = rtas_bounce_phys + rtas_bounce_offset; 178 rtas_bounce_offset += len; 179 180 return (phys); 181 } 182 183 static void 184 rtas_real_unmap(cell_t physaddr, void *buf, size_t len) 185 { 186 mtx_assert(&rtas_mtx, MA_OWNED); 187 188 if (physaddr == 0) 189 return; 190 191 memcpy(buf, rtas_bounce_virt + (physaddr - rtas_bounce_phys), len); 192 } 193 194 /* Check if we have RTAS */ 195 int 196 rtas_exists(void) 197 { 198 return (rtas != 0); 199 } 200 201 /* Call an RTAS method by token */ 202 int 203 rtas_call_method(cell_t token, int nargs, int nreturns, ...) 204 { 205 vm_offset_t argsptr; 206 faultbuf env, *oldfaultbuf; 207 va_list ap; 208 struct { 209 cell_t token; 210 cell_t nargs; 211 cell_t nreturns; 212 cell_t args_n_results[12]; 213 } args; 214 int n, result; 215 216 if (!rtas_exists() || nargs + nreturns > 12) 217 return (-1); 218 219 args.token = token; 220 va_start(ap, nreturns); 221 222 mtx_lock_spin(&rtas_mtx); 223 rtas_bounce_offset = 0; 224 225 args.nargs = nargs; 226 args.nreturns = nreturns; 227 228 for (n = 0; n < nargs; n++) 229 args.args_n_results[n] = va_arg(ap, cell_t); 230 231 argsptr = rtas_real_map(&args, sizeof(args)); 232 233 /* Get rid of any stale machine checks that have been waiting. */ 234 __asm __volatile ("sync; isync"); 235 oldfaultbuf = curthread->td_pcb->pcb_onfault; 236 if (!setfault(env)) { 237 __asm __volatile ("sync"); 238 result = rtascall(argsptr, rtas_private_data); 239 __asm __volatile ("sync; isync"); 240 } else { 241 result = RTAS_HW_ERROR; 242 } 243 curthread->td_pcb->pcb_onfault = oldfaultbuf; 244 __asm __volatile ("sync"); 245 246 rtas_real_unmap(argsptr, &args, sizeof(args)); 247 mtx_unlock_spin(&rtas_mtx); 248 249 if (result < 0) 250 return (result); 251 252 for (n = nargs; n < nargs + nreturns; n++) 253 *va_arg(ap, cell_t *) = args.args_n_results[n]; 254 return (result); 255 } 256 257 /* Look up an RTAS token */ 258 cell_t 259 rtas_token_lookup(const char *method) 260 { 261 cell_t token; 262 263 if (!rtas_exists()) 264 return (-1); 265 266 if (OF_getencprop(rtas, method, &token, sizeof(token)) == -1) 267 return (-1); 268 269 return (token); 270 } 271 272 273