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/rtas.h> 45 #include <machine/stdarg.h> 46 47 #include <dev/ofw/openfirm.h> 48 49 static MALLOC_DEFINE(M_RTAS, "rtas", "Run Time Abstraction Service"); 50 51 static vm_offset_t rtas_bounce_phys; 52 static caddr_t rtas_bounce_virt; 53 static off_t rtas_bounce_offset; 54 static size_t rtas_bounce_size; 55 static uintptr_t rtas_private_data; 56 static struct mtx rtas_mtx; 57 static phandle_t rtas; 58 59 /* From ofwcall.S */ 60 int rtascall(vm_offset_t callbuffer, uintptr_t rtas_privdat); 61 extern uintptr_t rtas_entry; 62 extern register_t rtasmsr; 63 64 /* 65 * After the VM is up, allocate RTAS memory and instantiate it 66 */ 67 68 static void rtas_setup(void *); 69 70 SYSINIT(rtas_setup, SI_SUB_KMEM, SI_ORDER_ANY, rtas_setup, NULL); 71 72 static void 73 rtas_setup(void *junk) 74 { 75 ihandle_t rtasi; 76 cell_t rtas_size = 0, rtas_ptr; 77 char path[31]; 78 int result; 79 80 rtas = OF_finddevice("/rtas"); 81 if (rtas == -1) { 82 rtas = 0; 83 return; 84 } 85 OF_package_to_path(rtas, path, sizeof(path)); 86 87 mtx_init(&rtas_mtx, "RTAS", NULL, MTX_SPIN); 88 89 /* RTAS must be called with everything turned off in MSR */ 90 rtasmsr = mfmsr(); 91 rtasmsr &= ~(PSL_IR | PSL_DR | PSL_EE | PSL_SE); 92 #ifdef __powerpc64__ 93 rtasmsr &= ~PSL_SF; 94 #endif 95 96 /* 97 * Allocate rtas_size + one page of contiguous, wired physical memory 98 * that can fit into a 32-bit address space and accessed from real mode. 99 * This is used both to bounce arguments and for RTAS private data. 100 * 101 * It must be 4KB-aligned and not cross a 256 MB boundary. 102 */ 103 104 OF_getencprop(rtas, "rtas-size", &rtas_size, sizeof(rtas_size)); 105 rtas_size = round_page(rtas_size); 106 rtas_bounce_virt = contigmalloc(rtas_size + PAGE_SIZE, M_RTAS, 0, 0, 107 ulmin(platform_real_maxaddr(), BUS_SPACE_MAXADDR_32BIT), 108 4096, 256*1024*1024); 109 110 rtas_private_data = vtophys(rtas_bounce_virt); 111 rtas_bounce_virt += rtas_size; /* Actual bounce area */ 112 rtas_bounce_phys = vtophys(rtas_bounce_virt); 113 rtas_bounce_size = PAGE_SIZE; 114 115 /* 116 * Instantiate RTAS. We always use the 32-bit version. 117 */ 118 119 if (OF_hasprop(rtas, "linux,rtas-entry") && 120 OF_hasprop(rtas, "linux,rtas-base")) { 121 OF_getencprop(rtas, "linux,rtas-base", &rtas_ptr, 122 sizeof(rtas_ptr)); 123 rtas_private_data = rtas_ptr; 124 OF_getencprop(rtas, "linux,rtas-entry", &rtas_ptr, 125 sizeof(rtas_ptr)); 126 } else { 127 rtasi = OF_open(path); 128 if (rtasi == 0) { 129 rtas = 0; 130 printf("Error initializing RTAS: could not open " 131 "node\n"); 132 return; 133 } 134 135 result = OF_call_method("instantiate-rtas", rtasi, 1, 1, 136 (cell_t)rtas_private_data, &rtas_ptr); 137 OF_close(rtasi); 138 139 if (result != 0) { 140 rtas = 0; 141 rtas_ptr = 0; 142 printf("Error initializing RTAS (%d)\n", result); 143 return; 144 } 145 } 146 147 rtas_entry = (uintptr_t)(rtas_ptr); 148 } 149 150 static cell_t 151 rtas_real_map(const void *buf, size_t len) 152 { 153 cell_t phys; 154 155 mtx_assert(&rtas_mtx, MA_OWNED); 156 157 /* 158 * Make sure the bounce page offset satisfies any reasonable 159 * alignment constraint. 160 */ 161 rtas_bounce_offset += sizeof(register_t) - 162 (rtas_bounce_offset % sizeof(register_t)); 163 164 if (rtas_bounce_offset + len > rtas_bounce_size) { 165 panic("Oversize RTAS call!"); 166 return 0; 167 } 168 169 if (buf != NULL) 170 memcpy(rtas_bounce_virt + rtas_bounce_offset, buf, len); 171 else 172 return (0); 173 174 phys = rtas_bounce_phys + rtas_bounce_offset; 175 rtas_bounce_offset += len; 176 177 return (phys); 178 } 179 180 static void 181 rtas_real_unmap(cell_t physaddr, void *buf, size_t len) 182 { 183 mtx_assert(&rtas_mtx, MA_OWNED); 184 185 if (physaddr == 0) 186 return; 187 188 memcpy(buf, rtas_bounce_virt + (physaddr - rtas_bounce_phys), len); 189 } 190 191 /* Check if we have RTAS */ 192 int 193 rtas_exists(void) 194 { 195 return (rtas != 0); 196 } 197 198 /* Call an RTAS method by token */ 199 int 200 rtas_call_method(cell_t token, int nargs, int nreturns, ...) 201 { 202 vm_offset_t argsptr; 203 jmp_buf env, *oldfaultbuf; 204 va_list ap; 205 struct { 206 cell_t token; 207 cell_t nargs; 208 cell_t nreturns; 209 cell_t args_n_results[12]; 210 } args; 211 int n, result; 212 213 if (!rtas_exists() || nargs + nreturns > 12) 214 return (-1); 215 216 args.token = token; 217 va_start(ap, nreturns); 218 219 mtx_lock_spin(&rtas_mtx); 220 rtas_bounce_offset = 0; 221 222 args.nargs = nargs; 223 args.nreturns = nreturns; 224 225 for (n = 0; n < nargs; n++) 226 args.args_n_results[n] = va_arg(ap, cell_t); 227 228 argsptr = rtas_real_map(&args, sizeof(args)); 229 230 /* Get rid of any stale machine checks that have been waiting. */ 231 __asm __volatile ("sync; isync"); 232 oldfaultbuf = curthread->td_pcb->pcb_onfault; 233 curthread->td_pcb->pcb_onfault = &env; 234 if (!setjmp(env)) { 235 __asm __volatile ("sync"); 236 result = rtascall(argsptr, rtas_private_data); 237 __asm __volatile ("sync; isync"); 238 } else { 239 result = RTAS_HW_ERROR; 240 } 241 curthread->td_pcb->pcb_onfault = oldfaultbuf; 242 __asm __volatile ("sync"); 243 244 rtas_real_unmap(argsptr, &args, sizeof(args)); 245 mtx_unlock_spin(&rtas_mtx); 246 247 if (result < 0) 248 return (result); 249 250 for (n = nargs; n < nargs + nreturns; n++) 251 *va_arg(ap, cell_t *) = args.args_n_results[n]; 252 return (result); 253 } 254 255 /* Look up an RTAS token */ 256 cell_t 257 rtas_token_lookup(const char *method) 258 { 259 cell_t token; 260 261 if (!rtas_exists()) 262 return (-1); 263 264 if (OF_getencprop(rtas, method, &token, sizeof(token)) == -1) 265 return (-1); 266 267 return (token); 268 } 269 270 271