1 /* 2 * ePAPR hcall interface 3 * 4 * Copyright 2008-2011 Freescale Semiconductor, Inc. 5 * 6 * Author: Timur Tabi <timur@freescale.com> 7 * 8 * This file is provided under a dual BSD/GPL license. When using or 9 * redistributing this file, you may do so under either license. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions are met: 13 * * Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * * Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * * Neither the name of Freescale Semiconductor nor the 19 * names of its contributors may be used to endorse or promote products 20 * derived from this software without specific prior written permission. 21 * 22 * 23 * ALTERNATIVELY, this software may be distributed under the terms of the 24 * GNU General Public License ("GPL") as published by the Free Software 25 * Foundation, either version 2 of that License or (at your option) any 26 * later version. 27 * 28 * THIS SOFTWARE IS PROVIDED BY Freescale Semiconductor ``AS IS'' AND ANY 29 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 30 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 31 * DISCLAIMED. IN NO EVENT SHALL Freescale Semiconductor BE LIABLE FOR ANY 32 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 33 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 34 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 35 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 36 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 37 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 38 */ 39 40 /* A "hypercall" is an "sc 1" instruction. This header file file provides C 41 * wrapper functions for the ePAPR hypervisor interface. It is inteded 42 * for use by Linux device drivers and other operating systems. 43 * 44 * The hypercalls are implemented as inline assembly, rather than assembly 45 * language functions in a .S file, for optimization. It allows 46 * the caller to issue the hypercall instruction directly, improving both 47 * performance and memory footprint. 48 */ 49 50 #ifndef _EPAPR_HCALLS_H 51 #define _EPAPR_HCALLS_H 52 53 #include <linux/types.h> 54 #include <linux/errno.h> 55 #include <asm/byteorder.h> 56 57 #define EV_BYTE_CHANNEL_SEND 1 58 #define EV_BYTE_CHANNEL_RECEIVE 2 59 #define EV_BYTE_CHANNEL_POLL 3 60 #define EV_INT_SET_CONFIG 4 61 #define EV_INT_GET_CONFIG 5 62 #define EV_INT_SET_MASK 6 63 #define EV_INT_GET_MASK 7 64 #define EV_INT_IACK 9 65 #define EV_INT_EOI 10 66 #define EV_INT_SEND_IPI 11 67 #define EV_INT_SET_TASK_PRIORITY 12 68 #define EV_INT_GET_TASK_PRIORITY 13 69 #define EV_DOORBELL_SEND 14 70 #define EV_MSGSND 15 71 #define EV_IDLE 16 72 73 /* vendor ID: epapr */ 74 #define EV_LOCAL_VENDOR_ID 0 /* for private use */ 75 #define EV_EPAPR_VENDOR_ID 1 76 #define EV_FSL_VENDOR_ID 2 /* Freescale Semiconductor */ 77 #define EV_IBM_VENDOR_ID 3 /* IBM */ 78 #define EV_GHS_VENDOR_ID 4 /* Green Hills Software */ 79 #define EV_ENEA_VENDOR_ID 5 /* Enea */ 80 #define EV_WR_VENDOR_ID 6 /* Wind River Systems */ 81 #define EV_AMCC_VENDOR_ID 7 /* Applied Micro Circuits */ 82 #define EV_KVM_VENDOR_ID 42 /* KVM */ 83 84 /* The max number of bytes that a byte channel can send or receive per call */ 85 #define EV_BYTE_CHANNEL_MAX_BYTES 16 86 87 88 #define _EV_HCALL_TOKEN(id, num) (((id) << 16) | (num)) 89 #define EV_HCALL_TOKEN(hcall_num) _EV_HCALL_TOKEN(EV_EPAPR_VENDOR_ID, hcall_num) 90 91 /* epapr error codes */ 92 #define EV_EPERM 1 /* Operation not permitted */ 93 #define EV_ENOENT 2 /* Entry Not Found */ 94 #define EV_EIO 3 /* I/O error occured */ 95 #define EV_EAGAIN 4 /* The operation had insufficient 96 * resources to complete and should be 97 * retried 98 */ 99 #define EV_ENOMEM 5 /* There was insufficient memory to 100 * complete the operation */ 101 #define EV_EFAULT 6 /* Bad guest address */ 102 #define EV_ENODEV 7 /* No such device */ 103 #define EV_EINVAL 8 /* An argument supplied to the hcall 104 was out of range or invalid */ 105 #define EV_INTERNAL 9 /* An internal error occured */ 106 #define EV_CONFIG 10 /* A configuration error was detected */ 107 #define EV_INVALID_STATE 11 /* The object is in an invalid state */ 108 #define EV_UNIMPLEMENTED 12 /* Unimplemented hypercall */ 109 #define EV_BUFFER_OVERFLOW 13 /* Caller-supplied buffer too small */ 110 111 /* 112 * Hypercall register clobber list 113 * 114 * These macros are used to define the list of clobbered registers during a 115 * hypercall. Technically, registers r0 and r3-r12 are always clobbered, 116 * but the gcc inline assembly syntax does not allow us to specify registers 117 * on the clobber list that are also on the input/output list. Therefore, 118 * the lists of clobbered registers depends on the number of register 119 * parmeters ("+r" and "=r") passed to the hypercall. 120 * 121 * Each assembly block should use one of the HCALL_CLOBBERSx macros. As a 122 * general rule, 'x' is the number of parameters passed to the assembly 123 * block *except* for r11. 124 * 125 * If you're not sure, just use the smallest value of 'x' that does not 126 * generate a compilation error. Because these are static inline functions, 127 * the compiler will only check the clobber list for a function if you 128 * compile code that calls that function. 129 * 130 * r3 and r11 are not included in any clobbers list because they are always 131 * listed as output registers. 132 * 133 * XER, CTR, and LR are currently listed as clobbers because it's uncertain 134 * whether they will be clobbered. 135 * 136 * Note that r11 can be used as an output parameter. 137 * 138 * The "memory" clobber is only necessary for hcalls where the Hypervisor 139 * will read or write guest memory. However, we add it to all hcalls because 140 * the impact is minimal, and we want to ensure that it's present for the 141 * hcalls that need it. 142 */ 143 144 /* List of common clobbered registers. Do not use this macro. */ 145 #define EV_HCALL_CLOBBERS "r0", "r12", "xer", "ctr", "lr", "cc", "memory" 146 147 #define EV_HCALL_CLOBBERS8 EV_HCALL_CLOBBERS 148 #define EV_HCALL_CLOBBERS7 EV_HCALL_CLOBBERS8, "r10" 149 #define EV_HCALL_CLOBBERS6 EV_HCALL_CLOBBERS7, "r9" 150 #define EV_HCALL_CLOBBERS5 EV_HCALL_CLOBBERS6, "r8" 151 #define EV_HCALL_CLOBBERS4 EV_HCALL_CLOBBERS5, "r7" 152 #define EV_HCALL_CLOBBERS3 EV_HCALL_CLOBBERS4, "r6" 153 #define EV_HCALL_CLOBBERS2 EV_HCALL_CLOBBERS3, "r5" 154 #define EV_HCALL_CLOBBERS1 EV_HCALL_CLOBBERS2, "r4" 155 156 extern bool epapr_paravirt_enabled; 157 extern u32 epapr_hypercall_start[]; 158 159 /* 160 * We use "uintptr_t" to define a register because it's guaranteed to be a 161 * 32-bit integer on a 32-bit platform, and a 64-bit integer on a 64-bit 162 * platform. 163 * 164 * All registers are either input/output or output only. Registers that are 165 * initialized before making the hypercall are input/output. All 166 * input/output registers are represented with "+r". Output-only registers 167 * are represented with "=r". Do not specify any unused registers. The 168 * clobber list will tell the compiler that the hypercall modifies those 169 * registers, which is good enough. 170 */ 171 172 /** 173 * ev_int_set_config - configure the specified interrupt 174 * @interrupt: the interrupt number 175 * @config: configuration for this interrupt 176 * @priority: interrupt priority 177 * @destination: destination CPU number 178 * 179 * Returns 0 for success, or an error code. 180 */ 181 static inline unsigned int ev_int_set_config(unsigned int interrupt, 182 uint32_t config, unsigned int priority, uint32_t destination) 183 { 184 register uintptr_t r11 __asm__("r11"); 185 register uintptr_t r3 __asm__("r3"); 186 register uintptr_t r4 __asm__("r4"); 187 register uintptr_t r5 __asm__("r5"); 188 register uintptr_t r6 __asm__("r6"); 189 190 r11 = EV_HCALL_TOKEN(EV_INT_SET_CONFIG); 191 r3 = interrupt; 192 r4 = config; 193 r5 = priority; 194 r6 = destination; 195 196 __asm__ __volatile__ ("sc 1" 197 : "+r" (r11), "+r" (r3), "+r" (r4), "+r" (r5), "+r" (r6) 198 : : EV_HCALL_CLOBBERS4 199 ); 200 201 return r3; 202 } 203 204 /** 205 * ev_int_get_config - return the config of the specified interrupt 206 * @interrupt: the interrupt number 207 * @config: returned configuration for this interrupt 208 * @priority: returned interrupt priority 209 * @destination: returned destination CPU number 210 * 211 * Returns 0 for success, or an error code. 212 */ 213 static inline unsigned int ev_int_get_config(unsigned int interrupt, 214 uint32_t *config, unsigned int *priority, uint32_t *destination) 215 { 216 register uintptr_t r11 __asm__("r11"); 217 register uintptr_t r3 __asm__("r3"); 218 register uintptr_t r4 __asm__("r4"); 219 register uintptr_t r5 __asm__("r5"); 220 register uintptr_t r6 __asm__("r6"); 221 222 r11 = EV_HCALL_TOKEN(EV_INT_GET_CONFIG); 223 r3 = interrupt; 224 225 __asm__ __volatile__ ("sc 1" 226 : "+r" (r11), "+r" (r3), "=r" (r4), "=r" (r5), "=r" (r6) 227 : : EV_HCALL_CLOBBERS4 228 ); 229 230 *config = r4; 231 *priority = r5; 232 *destination = r6; 233 234 return r3; 235 } 236 237 /** 238 * ev_int_set_mask - sets the mask for the specified interrupt source 239 * @interrupt: the interrupt number 240 * @mask: 0=enable interrupts, 1=disable interrupts 241 * 242 * Returns 0 for success, or an error code. 243 */ 244 static inline unsigned int ev_int_set_mask(unsigned int interrupt, 245 unsigned int mask) 246 { 247 register uintptr_t r11 __asm__("r11"); 248 register uintptr_t r3 __asm__("r3"); 249 register uintptr_t r4 __asm__("r4"); 250 251 r11 = EV_HCALL_TOKEN(EV_INT_SET_MASK); 252 r3 = interrupt; 253 r4 = mask; 254 255 __asm__ __volatile__ ("sc 1" 256 : "+r" (r11), "+r" (r3), "+r" (r4) 257 : : EV_HCALL_CLOBBERS2 258 ); 259 260 return r3; 261 } 262 263 /** 264 * ev_int_get_mask - returns the mask for the specified interrupt source 265 * @interrupt: the interrupt number 266 * @mask: returned mask for this interrupt (0=enabled, 1=disabled) 267 * 268 * Returns 0 for success, or an error code. 269 */ 270 static inline unsigned int ev_int_get_mask(unsigned int interrupt, 271 unsigned int *mask) 272 { 273 register uintptr_t r11 __asm__("r11"); 274 register uintptr_t r3 __asm__("r3"); 275 register uintptr_t r4 __asm__("r4"); 276 277 r11 = EV_HCALL_TOKEN(EV_INT_GET_MASK); 278 r3 = interrupt; 279 280 __asm__ __volatile__ ("sc 1" 281 : "+r" (r11), "+r" (r3), "=r" (r4) 282 : : EV_HCALL_CLOBBERS2 283 ); 284 285 *mask = r4; 286 287 return r3; 288 } 289 290 /** 291 * ev_int_eoi - signal the end of interrupt processing 292 * @interrupt: the interrupt number 293 * 294 * This function signals the end of processing for the the specified 295 * interrupt, which must be the interrupt currently in service. By 296 * definition, this is also the highest-priority interrupt. 297 * 298 * Returns 0 for success, or an error code. 299 */ 300 static inline unsigned int ev_int_eoi(unsigned int interrupt) 301 { 302 register uintptr_t r11 __asm__("r11"); 303 register uintptr_t r3 __asm__("r3"); 304 305 r11 = EV_HCALL_TOKEN(EV_INT_EOI); 306 r3 = interrupt; 307 308 __asm__ __volatile__ ("sc 1" 309 : "+r" (r11), "+r" (r3) 310 : : EV_HCALL_CLOBBERS1 311 ); 312 313 return r3; 314 } 315 316 /** 317 * ev_byte_channel_send - send characters to a byte stream 318 * @handle: byte stream handle 319 * @count: (input) num of chars to send, (output) num chars sent 320 * @buffer: pointer to a 16-byte buffer 321 * 322 * @buffer must be at least 16 bytes long, because all 16 bytes will be 323 * read from memory into registers, even if count < 16. 324 * 325 * Returns 0 for success, or an error code. 326 */ 327 static inline unsigned int ev_byte_channel_send(unsigned int handle, 328 unsigned int *count, const char buffer[EV_BYTE_CHANNEL_MAX_BYTES]) 329 { 330 register uintptr_t r11 __asm__("r11"); 331 register uintptr_t r3 __asm__("r3"); 332 register uintptr_t r4 __asm__("r4"); 333 register uintptr_t r5 __asm__("r5"); 334 register uintptr_t r6 __asm__("r6"); 335 register uintptr_t r7 __asm__("r7"); 336 register uintptr_t r8 __asm__("r8"); 337 const uint32_t *p = (const uint32_t *) buffer; 338 339 r11 = EV_HCALL_TOKEN(EV_BYTE_CHANNEL_SEND); 340 r3 = handle; 341 r4 = *count; 342 r5 = be32_to_cpu(p[0]); 343 r6 = be32_to_cpu(p[1]); 344 r7 = be32_to_cpu(p[2]); 345 r8 = be32_to_cpu(p[3]); 346 347 __asm__ __volatile__ ("sc 1" 348 : "+r" (r11), "+r" (r3), 349 "+r" (r4), "+r" (r5), "+r" (r6), "+r" (r7), "+r" (r8) 350 : : EV_HCALL_CLOBBERS6 351 ); 352 353 *count = r4; 354 355 return r3; 356 } 357 358 /** 359 * ev_byte_channel_receive - fetch characters from a byte channel 360 * @handle: byte channel handle 361 * @count: (input) max num of chars to receive, (output) num chars received 362 * @buffer: pointer to a 16-byte buffer 363 * 364 * The size of @buffer must be at least 16 bytes, even if you request fewer 365 * than 16 characters, because we always write 16 bytes to @buffer. This is 366 * for performance reasons. 367 * 368 * Returns 0 for success, or an error code. 369 */ 370 static inline unsigned int ev_byte_channel_receive(unsigned int handle, 371 unsigned int *count, char buffer[EV_BYTE_CHANNEL_MAX_BYTES]) 372 { 373 register uintptr_t r11 __asm__("r11"); 374 register uintptr_t r3 __asm__("r3"); 375 register uintptr_t r4 __asm__("r4"); 376 register uintptr_t r5 __asm__("r5"); 377 register uintptr_t r6 __asm__("r6"); 378 register uintptr_t r7 __asm__("r7"); 379 register uintptr_t r8 __asm__("r8"); 380 uint32_t *p = (uint32_t *) buffer; 381 382 r11 = EV_HCALL_TOKEN(EV_BYTE_CHANNEL_RECEIVE); 383 r3 = handle; 384 r4 = *count; 385 386 __asm__ __volatile__ ("sc 1" 387 : "+r" (r11), "+r" (r3), "+r" (r4), 388 "=r" (r5), "=r" (r6), "=r" (r7), "=r" (r8) 389 : : EV_HCALL_CLOBBERS6 390 ); 391 392 *count = r4; 393 p[0] = cpu_to_be32(r5); 394 p[1] = cpu_to_be32(r6); 395 p[2] = cpu_to_be32(r7); 396 p[3] = cpu_to_be32(r8); 397 398 return r3; 399 } 400 401 /** 402 * ev_byte_channel_poll - returns the status of the byte channel buffers 403 * @handle: byte channel handle 404 * @rx_count: returned count of bytes in receive queue 405 * @tx_count: returned count of free space in transmit queue 406 * 407 * This function reports the amount of data in the receive queue (i.e. the 408 * number of bytes you can read), and the amount of free space in the transmit 409 * queue (i.e. the number of bytes you can write). 410 * 411 * Returns 0 for success, or an error code. 412 */ 413 static inline unsigned int ev_byte_channel_poll(unsigned int handle, 414 unsigned int *rx_count, unsigned int *tx_count) 415 { 416 register uintptr_t r11 __asm__("r11"); 417 register uintptr_t r3 __asm__("r3"); 418 register uintptr_t r4 __asm__("r4"); 419 register uintptr_t r5 __asm__("r5"); 420 421 r11 = EV_HCALL_TOKEN(EV_BYTE_CHANNEL_POLL); 422 r3 = handle; 423 424 __asm__ __volatile__ ("sc 1" 425 : "+r" (r11), "+r" (r3), "=r" (r4), "=r" (r5) 426 : : EV_HCALL_CLOBBERS3 427 ); 428 429 *rx_count = r4; 430 *tx_count = r5; 431 432 return r3; 433 } 434 435 /** 436 * ev_int_iack - acknowledge an interrupt 437 * @handle: handle to the target interrupt controller 438 * @vector: returned interrupt vector 439 * 440 * If handle is zero, the function returns the next interrupt source 441 * number to be handled irrespective of the hierarchy or cascading 442 * of interrupt controllers. If non-zero, specifies a handle to the 443 * interrupt controller that is the target of the acknowledge. 444 * 445 * Returns 0 for success, or an error code. 446 */ 447 static inline unsigned int ev_int_iack(unsigned int handle, 448 unsigned int *vector) 449 { 450 register uintptr_t r11 __asm__("r11"); 451 register uintptr_t r3 __asm__("r3"); 452 register uintptr_t r4 __asm__("r4"); 453 454 r11 = EV_HCALL_TOKEN(EV_INT_IACK); 455 r3 = handle; 456 457 __asm__ __volatile__ ("sc 1" 458 : "+r" (r11), "+r" (r3), "=r" (r4) 459 : : EV_HCALL_CLOBBERS2 460 ); 461 462 *vector = r4; 463 464 return r3; 465 } 466 467 /** 468 * ev_doorbell_send - send a doorbell to another partition 469 * @handle: doorbell send handle 470 * 471 * Returns 0 for success, or an error code. 472 */ 473 static inline unsigned int ev_doorbell_send(unsigned int handle) 474 { 475 register uintptr_t r11 __asm__("r11"); 476 register uintptr_t r3 __asm__("r3"); 477 478 r11 = EV_HCALL_TOKEN(EV_DOORBELL_SEND); 479 r3 = handle; 480 481 __asm__ __volatile__ ("sc 1" 482 : "+r" (r11), "+r" (r3) 483 : : EV_HCALL_CLOBBERS1 484 ); 485 486 return r3; 487 } 488 489 /** 490 * ev_idle -- wait for next interrupt on this core 491 * 492 * Returns 0 for success, or an error code. 493 */ 494 static inline unsigned int ev_idle(void) 495 { 496 register uintptr_t r11 __asm__("r11"); 497 register uintptr_t r3 __asm__("r3"); 498 499 r11 = EV_HCALL_TOKEN(EV_IDLE); 500 501 __asm__ __volatile__ ("sc 1" 502 : "+r" (r11), "=r" (r3) 503 : : EV_HCALL_CLOBBERS1 504 ); 505 506 return r3; 507 } 508 509 #endif 510