1 /* 2 * ARM gdb server stub 3 * 4 * Copyright (c) 2003-2005 Fabrice Bellard 5 * Copyright (c) 2013 SUSE LINUX Products GmbH 6 * 7 * This library is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * This library is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with this library; if not, see <http://www.gnu.org/licenses/>. 19 */ 20 #include "qemu/osdep.h" 21 #include "cpu.h" 22 #include "exec/gdbstub.h" 23 24 typedef struct RegisterSysregXmlParam { 25 CPUState *cs; 26 GString *s; 27 int n; 28 } RegisterSysregXmlParam; 29 30 /* Old gdb always expect FPA registers. Newer (xml-aware) gdb only expect 31 whatever the target description contains. Due to a historical mishap 32 the FPA registers appear in between core integer regs and the CPSR. 33 We hack round this by giving the FPA regs zero size when talking to a 34 newer gdb. */ 35 36 int arm_cpu_gdb_read_register(CPUState *cs, GByteArray *mem_buf, int n) 37 { 38 ARMCPU *cpu = ARM_CPU(cs); 39 CPUARMState *env = &cpu->env; 40 41 if (n < 16) { 42 /* Core integer register. */ 43 return gdb_get_reg32(mem_buf, env->regs[n]); 44 } 45 if (n < 24) { 46 /* FPA registers. */ 47 if (gdb_has_xml) { 48 return 0; 49 } 50 return gdb_get_zeroes(mem_buf, 12); 51 } 52 switch (n) { 53 case 24: 54 /* FPA status register. */ 55 if (gdb_has_xml) { 56 return 0; 57 } 58 return gdb_get_reg32(mem_buf, 0); 59 case 25: 60 /* CPSR, or XPSR for M-profile */ 61 if (arm_feature(env, ARM_FEATURE_M)) { 62 return gdb_get_reg32(mem_buf, xpsr_read(env)); 63 } else { 64 return gdb_get_reg32(mem_buf, cpsr_read(env)); 65 } 66 } 67 /* Unknown register. */ 68 return 0; 69 } 70 71 int arm_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n) 72 { 73 ARMCPU *cpu = ARM_CPU(cs); 74 CPUARMState *env = &cpu->env; 75 uint32_t tmp; 76 77 tmp = ldl_p(mem_buf); 78 79 /* Mask out low bit of PC to workaround gdb bugs. This will probably 80 cause problems if we ever implement the Jazelle DBX extensions. */ 81 if (n == 15) { 82 tmp &= ~1; 83 } 84 85 if (n < 16) { 86 /* Core integer register. */ 87 env->regs[n] = tmp; 88 return 4; 89 } 90 if (n < 24) { /* 16-23 */ 91 /* FPA registers (ignored). */ 92 if (gdb_has_xml) { 93 return 0; 94 } 95 return 12; 96 } 97 switch (n) { 98 case 24: 99 /* FPA status register (ignored). */ 100 if (gdb_has_xml) { 101 return 0; 102 } 103 return 4; 104 case 25: 105 /* CPSR, or XPSR for M-profile */ 106 if (arm_feature(env, ARM_FEATURE_M)) { 107 /* 108 * Don't allow writing to XPSR.Exception as it can cause 109 * a transition into or out of handler mode (it's not 110 * writeable via the MSR insn so this is a reasonable 111 * restriction). Other fields are safe to update. 112 */ 113 xpsr_write(env, tmp, ~XPSR_EXCP); 114 } else { 115 cpsr_write(env, tmp, 0xffffffff, CPSRWriteByGDBStub); 116 } 117 return 4; 118 } 119 /* Unknown register. */ 120 return 0; 121 } 122 123 static void arm_gen_one_xml_sysreg_tag(GString *s, DynamicGDBXMLInfo *dyn_xml, 124 ARMCPRegInfo *ri, uint32_t ri_key, 125 int bitsize, int regnum) 126 { 127 g_string_append_printf(s, "<reg name=\"%s\"", ri->name); 128 g_string_append_printf(s, " bitsize=\"%d\"", bitsize); 129 g_string_append_printf(s, " regnum=\"%d\"", regnum); 130 g_string_append_printf(s, " group=\"cp_regs\"/>"); 131 dyn_xml->data.cpregs.keys[dyn_xml->num] = ri_key; 132 dyn_xml->num++; 133 } 134 135 static void arm_register_sysreg_for_xml(gpointer key, gpointer value, 136 gpointer p) 137 { 138 uint32_t ri_key = *(uint32_t *)key; 139 ARMCPRegInfo *ri = value; 140 RegisterSysregXmlParam *param = (RegisterSysregXmlParam *)p; 141 GString *s = param->s; 142 ARMCPU *cpu = ARM_CPU(param->cs); 143 CPUARMState *env = &cpu->env; 144 DynamicGDBXMLInfo *dyn_xml = &cpu->dyn_sysreg_xml; 145 146 if (!(ri->type & (ARM_CP_NO_RAW | ARM_CP_NO_GDB))) { 147 if (arm_feature(env, ARM_FEATURE_AARCH64)) { 148 if (ri->state == ARM_CP_STATE_AA64) { 149 arm_gen_one_xml_sysreg_tag(s , dyn_xml, ri, ri_key, 64, 150 param->n++); 151 } 152 } else { 153 if (ri->state == ARM_CP_STATE_AA32) { 154 if (!arm_feature(env, ARM_FEATURE_EL3) && 155 (ri->secure & ARM_CP_SECSTATE_S)) { 156 return; 157 } 158 if (ri->type & ARM_CP_64BIT) { 159 arm_gen_one_xml_sysreg_tag(s , dyn_xml, ri, ri_key, 64, 160 param->n++); 161 } else { 162 arm_gen_one_xml_sysreg_tag(s , dyn_xml, ri, ri_key, 32, 163 param->n++); 164 } 165 } 166 } 167 } 168 } 169 170 int arm_gen_dynamic_sysreg_xml(CPUState *cs, int base_reg) 171 { 172 ARMCPU *cpu = ARM_CPU(cs); 173 GString *s = g_string_new(NULL); 174 RegisterSysregXmlParam param = {cs, s, base_reg}; 175 176 cpu->dyn_sysreg_xml.num = 0; 177 cpu->dyn_sysreg_xml.data.cpregs.keys = g_new(uint32_t, g_hash_table_size(cpu->cp_regs)); 178 g_string_printf(s, "<?xml version=\"1.0\"?>"); 179 g_string_append_printf(s, "<!DOCTYPE target SYSTEM \"gdb-target.dtd\">"); 180 g_string_append_printf(s, "<feature name=\"org.qemu.gdb.arm.sys.regs\">"); 181 g_hash_table_foreach(cpu->cp_regs, arm_register_sysreg_for_xml, ¶m); 182 g_string_append_printf(s, "</feature>"); 183 cpu->dyn_sysreg_xml.desc = g_string_free(s, false); 184 return cpu->dyn_sysreg_xml.num; 185 } 186 187 struct TypeSize { 188 const char *gdb_type; 189 int size; 190 const char sz, suffix; 191 }; 192 193 static const struct TypeSize vec_lanes[] = { 194 /* quads */ 195 { "uint128", 128, 'q', 'u' }, 196 { "int128", 128, 'q', 's' }, 197 /* 64 bit */ 198 { "uint64", 64, 'd', 'u' }, 199 { "int64", 64, 'd', 's' }, 200 { "ieee_double", 64, 'd', 'f' }, 201 /* 32 bit */ 202 { "uint32", 32, 's', 'u' }, 203 { "int32", 32, 's', 's' }, 204 { "ieee_single", 32, 's', 'f' }, 205 /* 16 bit */ 206 { "uint16", 16, 'h', 'u' }, 207 { "int16", 16, 'h', 's' }, 208 /* 209 * TODO: currently there is no reliable way of telling 210 * if the remote gdb actually understands ieee_half so 211 * we don't expose it in the target description for now. 212 * { "ieee_half", 16, 'h', 'f' }, 213 */ 214 /* bytes */ 215 { "uint8", 8, 'b', 'u' }, 216 { "int8", 8, 'b', 's' }, 217 }; 218 219 220 int arm_gen_dynamic_svereg_xml(CPUState *cs, int base_reg) 221 { 222 ARMCPU *cpu = ARM_CPU(cs); 223 GString *s = g_string_new(NULL); 224 DynamicGDBXMLInfo *info = &cpu->dyn_svereg_xml; 225 g_autoptr(GString) ts = g_string_new(""); 226 int i, bits, reg_width = (cpu->sve_max_vq * 128); 227 info->num = 0; 228 g_string_printf(s, "<?xml version=\"1.0\"?>"); 229 g_string_append_printf(s, "<!DOCTYPE target SYSTEM \"gdb-target.dtd\">"); 230 g_string_append_printf(s, "<feature name=\"org.qemu.gdb.aarch64.sve\">"); 231 232 /* First define types and totals in a whole VL */ 233 for (i = 0; i < ARRAY_SIZE(vec_lanes); i++) { 234 int count = reg_width / vec_lanes[i].size; 235 g_string_printf(ts, "vq%d%c%c", count, 236 vec_lanes[i].sz, vec_lanes[i].suffix); 237 g_string_append_printf(s, 238 "<vector id=\"%s\" type=\"%s\" count=\"%d\"/>", 239 ts->str, vec_lanes[i].gdb_type, count); 240 } 241 /* 242 * Now define a union for each size group containing unsigned and 243 * signed and potentially float versions of each size from 128 to 244 * 8 bits. 245 */ 246 for (bits = 128; bits >= 8; bits /= 2) { 247 int count = reg_width / bits; 248 g_string_append_printf(s, "<union id=\"vq%dn\">", count); 249 for (i = 0; i < ARRAY_SIZE(vec_lanes); i++) { 250 if (vec_lanes[i].size == bits) { 251 g_string_append_printf(s, "<field name=\"%c\" type=\"vq%d%c%c\"/>", 252 vec_lanes[i].suffix, 253 count, 254 vec_lanes[i].sz, vec_lanes[i].suffix); 255 } 256 } 257 g_string_append(s, "</union>"); 258 } 259 /* And now the final union of unions */ 260 g_string_append(s, "<union id=\"vq\">"); 261 for (bits = 128; bits >= 8; bits /= 2) { 262 int count = reg_width / bits; 263 for (i = 0; i < ARRAY_SIZE(vec_lanes); i++) { 264 if (vec_lanes[i].size == bits) { 265 g_string_append_printf(s, "<field name=\"%c\" type=\"vq%dn\"/>", 266 vec_lanes[i].sz, count); 267 break; 268 } 269 } 270 } 271 g_string_append(s, "</union>"); 272 273 /* Then define each register in parts for each vq */ 274 for (i = 0; i < 32; i++) { 275 g_string_append_printf(s, 276 "<reg name=\"z%d\" bitsize=\"%d\"" 277 " regnum=\"%d\" group=\"vector\"" 278 " type=\"vq\"/>", 279 i, reg_width, base_reg++); 280 info->num++; 281 } 282 /* fpscr & status registers */ 283 g_string_append_printf(s, "<reg name=\"fpsr\" bitsize=\"32\"" 284 " regnum=\"%d\" group=\"float\"" 285 " type=\"int\"/>", base_reg++); 286 g_string_append_printf(s, "<reg name=\"fpcr\" bitsize=\"32\"" 287 " regnum=\"%d\" group=\"float\"" 288 " type=\"int\"/>", base_reg++); 289 info->num += 2; 290 /* 291 * Predicate registers aren't so big they are worth splitting up 292 * but we do need to define a type to hold the array of quad 293 * references. 294 */ 295 g_string_append_printf(s, 296 "<vector id=\"vqp\" type=\"uint16\" count=\"%d\"/>", 297 cpu->sve_max_vq); 298 for (i = 0; i < 16; i++) { 299 g_string_append_printf(s, 300 "<reg name=\"p%d\" bitsize=\"%d\"" 301 " regnum=\"%d\" group=\"vector\"" 302 " type=\"vqp\"/>", 303 i, cpu->sve_max_vq * 16, base_reg++); 304 info->num++; 305 } 306 g_string_append_printf(s, 307 "<reg name=\"ffr\" bitsize=\"%d\"" 308 " regnum=\"%d\" group=\"vector\"" 309 " type=\"vqp\"/>", 310 cpu->sve_max_vq * 16, base_reg++); 311 g_string_append_printf(s, 312 "<reg name=\"vg\" bitsize=\"64\"" 313 " regnum=\"%d\" group=\"vector\"" 314 " type=\"uint32\"/>", 315 base_reg++); 316 info->num += 2; 317 g_string_append_printf(s, "</feature>"); 318 cpu->dyn_svereg_xml.desc = g_string_free(s, false); 319 320 return cpu->dyn_svereg_xml.num; 321 } 322 323 324 const char *arm_gdb_get_dynamic_xml(CPUState *cs, const char *xmlname) 325 { 326 ARMCPU *cpu = ARM_CPU(cs); 327 328 if (strcmp(xmlname, "system-registers.xml") == 0) { 329 return cpu->dyn_sysreg_xml.desc; 330 } else if (strcmp(xmlname, "sve-registers.xml") == 0) { 331 return cpu->dyn_svereg_xml.desc; 332 } 333 return NULL; 334 } 335