1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (c) 2018 Chen-Yu Tsai 4 * 5 * Chen-Yu Tsai <wens@csie.org> 6 * 7 * arch/arm/mach-sunxi/mc_smp.c 8 * 9 * Based on Allwinner code, arch/arm/mach-exynos/mcpm-exynos.c, and 10 * arch/arm/mach-hisi/platmcpm.c 11 * Cluster cache enable trampoline code adapted from MCPM framework 12 */ 13 14 #include <linux/arm-cci.h> 15 #include <linux/cpu_pm.h> 16 #include <linux/delay.h> 17 #include <linux/io.h> 18 #include <linux/iopoll.h> 19 #include <linux/irqchip/arm-gic.h> 20 #include <linux/of.h> 21 #include <linux/of_address.h> 22 #include <linux/smp.h> 23 24 #include <asm/cacheflush.h> 25 #include <asm/cp15.h> 26 #include <asm/cputype.h> 27 #include <asm/idmap.h> 28 #include <asm/smp_plat.h> 29 #include <asm/suspend.h> 30 31 #define SUNXI_CPUS_PER_CLUSTER 4 32 #define SUNXI_NR_CLUSTERS 2 33 34 #define POLL_USEC 100 35 #define TIMEOUT_USEC 100000 36 37 #define CPUCFG_CX_CTRL_REG0(c) (0x10 * (c)) 38 #define CPUCFG_CX_CTRL_REG0_L1_RST_DISABLE(n) BIT(n) 39 #define CPUCFG_CX_CTRL_REG0_L1_RST_DISABLE_ALL 0xf 40 #define CPUCFG_CX_CTRL_REG0_L2_RST_DISABLE_A7 BIT(4) 41 #define CPUCFG_CX_CTRL_REG0_L2_RST_DISABLE_A15 BIT(0) 42 #define CPUCFG_CX_CTRL_REG1(c) (0x10 * (c) + 0x4) 43 #define CPUCFG_CX_CTRL_REG1_ACINACTM BIT(0) 44 #define CPUCFG_CX_STATUS(c) (0x30 + 0x4 * (c)) 45 #define CPUCFG_CX_STATUS_STANDBYWFI(n) BIT(16 + (n)) 46 #define CPUCFG_CX_STATUS_STANDBYWFIL2 BIT(0) 47 #define CPUCFG_CX_RST_CTRL(c) (0x80 + 0x4 * (c)) 48 #define CPUCFG_CX_RST_CTRL_DBG_SOC_RST BIT(24) 49 #define CPUCFG_CX_RST_CTRL_ETM_RST(n) BIT(20 + (n)) 50 #define CPUCFG_CX_RST_CTRL_ETM_RST_ALL (0xf << 20) 51 #define CPUCFG_CX_RST_CTRL_DBG_RST(n) BIT(16 + (n)) 52 #define CPUCFG_CX_RST_CTRL_DBG_RST_ALL (0xf << 16) 53 #define CPUCFG_CX_RST_CTRL_H_RST BIT(12) 54 #define CPUCFG_CX_RST_CTRL_L2_RST BIT(8) 55 #define CPUCFG_CX_RST_CTRL_CX_RST(n) BIT(4 + (n)) 56 #define CPUCFG_CX_RST_CTRL_CORE_RST(n) BIT(n) 57 #define CPUCFG_CX_RST_CTRL_CORE_RST_ALL (0xf << 0) 58 59 #define PRCM_CPU_PO_RST_CTRL(c) (0x4 + 0x4 * (c)) 60 #define PRCM_CPU_PO_RST_CTRL_CORE(n) BIT(n) 61 #define PRCM_CPU_PO_RST_CTRL_CORE_ALL 0xf 62 #define PRCM_PWROFF_GATING_REG(c) (0x100 + 0x4 * (c)) 63 /* The power off register for clusters are different from a80 and a83t */ 64 #define PRCM_PWROFF_GATING_REG_CLUSTER_SUN8I BIT(0) 65 #define PRCM_PWROFF_GATING_REG_CLUSTER_SUN9I BIT(4) 66 #define PRCM_PWROFF_GATING_REG_CORE(n) BIT(n) 67 #define PRCM_PWR_SWITCH_REG(c, cpu) (0x140 + 0x10 * (c) + 0x4 * (cpu)) 68 #define PRCM_CPU_SOFT_ENTRY_REG 0x164 69 70 /* R_CPUCFG registers, specific to sun8i-a83t */ 71 #define R_CPUCFG_CLUSTER_PO_RST_CTRL(c) (0x30 + (c) * 0x4) 72 #define R_CPUCFG_CLUSTER_PO_RST_CTRL_CORE(n) BIT(n) 73 #define R_CPUCFG_CPU_SOFT_ENTRY_REG 0x01a4 74 75 #define CPU0_SUPPORT_HOTPLUG_MAGIC0 0xFA50392F 76 #define CPU0_SUPPORT_HOTPLUG_MAGIC1 0x790DCA3A 77 78 static void __iomem *cpucfg_base; 79 static void __iomem *prcm_base; 80 static void __iomem *sram_b_smp_base; 81 static void __iomem *r_cpucfg_base; 82 83 extern void sunxi_mc_smp_secondary_startup(void); 84 extern void sunxi_mc_smp_resume(void); 85 static bool is_a83t; 86 87 static bool sunxi_core_is_cortex_a15(unsigned int core, unsigned int cluster) 88 { 89 struct device_node *node; 90 int cpu = cluster * SUNXI_CPUS_PER_CLUSTER + core; 91 bool is_compatible; 92 93 node = of_cpu_device_node_get(cpu); 94 95 /* In case of_cpu_device_node_get fails */ 96 if (!node) 97 node = of_get_cpu_node(cpu, NULL); 98 99 if (!node) { 100 /* 101 * There's no point in returning an error, since we 102 * would be mid way in a core or cluster power sequence. 103 */ 104 pr_err("%s: Couldn't get CPU cluster %u core %u device node\n", 105 __func__, cluster, core); 106 107 return false; 108 } 109 110 is_compatible = of_device_is_compatible(node, "arm,cortex-a15"); 111 of_node_put(node); 112 return is_compatible; 113 } 114 115 static int sunxi_cpu_power_switch_set(unsigned int cpu, unsigned int cluster, 116 bool enable) 117 { 118 u32 reg; 119 120 /* control sequence from Allwinner A80 user manual v1.2 PRCM section */ 121 reg = readl(prcm_base + PRCM_PWR_SWITCH_REG(cluster, cpu)); 122 if (enable) { 123 if (reg == 0x00) { 124 pr_debug("power clamp for cluster %u cpu %u already open\n", 125 cluster, cpu); 126 return 0; 127 } 128 129 writel(0xff, prcm_base + PRCM_PWR_SWITCH_REG(cluster, cpu)); 130 udelay(10); 131 writel(0xfe, prcm_base + PRCM_PWR_SWITCH_REG(cluster, cpu)); 132 udelay(10); 133 writel(0xf8, prcm_base + PRCM_PWR_SWITCH_REG(cluster, cpu)); 134 udelay(10); 135 writel(0xf0, prcm_base + PRCM_PWR_SWITCH_REG(cluster, cpu)); 136 udelay(10); 137 writel(0x00, prcm_base + PRCM_PWR_SWITCH_REG(cluster, cpu)); 138 udelay(10); 139 } else { 140 writel(0xff, prcm_base + PRCM_PWR_SWITCH_REG(cluster, cpu)); 141 udelay(10); 142 } 143 144 return 0; 145 } 146 147 static void sunxi_cpu0_hotplug_support_set(bool enable) 148 { 149 if (enable) { 150 writel(CPU0_SUPPORT_HOTPLUG_MAGIC0, sram_b_smp_base); 151 writel(CPU0_SUPPORT_HOTPLUG_MAGIC1, sram_b_smp_base + 0x4); 152 } else { 153 writel(0x0, sram_b_smp_base); 154 writel(0x0, sram_b_smp_base + 0x4); 155 } 156 } 157 158 static int sunxi_cpu_powerup(unsigned int cpu, unsigned int cluster) 159 { 160 u32 reg; 161 162 pr_debug("%s: cluster %u cpu %u\n", __func__, cluster, cpu); 163 if (cpu >= SUNXI_CPUS_PER_CLUSTER || cluster >= SUNXI_NR_CLUSTERS) 164 return -EINVAL; 165 166 /* Set hotplug support magic flags for cpu0 */ 167 if (cluster == 0 && cpu == 0) 168 sunxi_cpu0_hotplug_support_set(true); 169 170 /* assert processor power-on reset */ 171 reg = readl(prcm_base + PRCM_CPU_PO_RST_CTRL(cluster)); 172 reg &= ~PRCM_CPU_PO_RST_CTRL_CORE(cpu); 173 writel(reg, prcm_base + PRCM_CPU_PO_RST_CTRL(cluster)); 174 175 if (is_a83t) { 176 /* assert cpu power-on reset */ 177 reg = readl(r_cpucfg_base + 178 R_CPUCFG_CLUSTER_PO_RST_CTRL(cluster)); 179 reg &= ~(R_CPUCFG_CLUSTER_PO_RST_CTRL_CORE(cpu)); 180 writel(reg, r_cpucfg_base + 181 R_CPUCFG_CLUSTER_PO_RST_CTRL(cluster)); 182 udelay(10); 183 } 184 185 /* Cortex-A7: hold L1 reset disable signal low */ 186 if (!sunxi_core_is_cortex_a15(cpu, cluster)) { 187 reg = readl(cpucfg_base + CPUCFG_CX_CTRL_REG0(cluster)); 188 reg &= ~CPUCFG_CX_CTRL_REG0_L1_RST_DISABLE(cpu); 189 writel(reg, cpucfg_base + CPUCFG_CX_CTRL_REG0(cluster)); 190 } 191 192 /* assert processor related resets */ 193 reg = readl(cpucfg_base + CPUCFG_CX_RST_CTRL(cluster)); 194 reg &= ~CPUCFG_CX_RST_CTRL_DBG_RST(cpu); 195 196 /* 197 * Allwinner code also asserts resets for NEON on A15. According 198 * to ARM manuals, asserting power-on reset is sufficient. 199 */ 200 if (!sunxi_core_is_cortex_a15(cpu, cluster)) 201 reg &= ~CPUCFG_CX_RST_CTRL_ETM_RST(cpu); 202 203 writel(reg, cpucfg_base + CPUCFG_CX_RST_CTRL(cluster)); 204 205 /* open power switch */ 206 sunxi_cpu_power_switch_set(cpu, cluster, true); 207 208 /* Handle A83T bit swap */ 209 if (is_a83t) { 210 if (cpu == 0) 211 cpu = 4; 212 } 213 214 /* clear processor power gate */ 215 reg = readl(prcm_base + PRCM_PWROFF_GATING_REG(cluster)); 216 reg &= ~PRCM_PWROFF_GATING_REG_CORE(cpu); 217 writel(reg, prcm_base + PRCM_PWROFF_GATING_REG(cluster)); 218 udelay(20); 219 220 /* Handle A83T bit swap */ 221 if (is_a83t) { 222 if (cpu == 4) 223 cpu = 0; 224 } 225 226 /* de-assert processor power-on reset */ 227 reg = readl(prcm_base + PRCM_CPU_PO_RST_CTRL(cluster)); 228 reg |= PRCM_CPU_PO_RST_CTRL_CORE(cpu); 229 writel(reg, prcm_base + PRCM_CPU_PO_RST_CTRL(cluster)); 230 231 if (is_a83t) { 232 reg = readl(r_cpucfg_base + 233 R_CPUCFG_CLUSTER_PO_RST_CTRL(cluster)); 234 reg |= R_CPUCFG_CLUSTER_PO_RST_CTRL_CORE(cpu); 235 writel(reg, r_cpucfg_base + 236 R_CPUCFG_CLUSTER_PO_RST_CTRL(cluster)); 237 udelay(10); 238 } 239 240 /* de-assert all processor resets */ 241 reg = readl(cpucfg_base + CPUCFG_CX_RST_CTRL(cluster)); 242 reg |= CPUCFG_CX_RST_CTRL_DBG_RST(cpu); 243 reg |= CPUCFG_CX_RST_CTRL_CORE_RST(cpu); 244 if (!sunxi_core_is_cortex_a15(cpu, cluster)) 245 reg |= CPUCFG_CX_RST_CTRL_ETM_RST(cpu); 246 else 247 reg |= CPUCFG_CX_RST_CTRL_CX_RST(cpu); /* NEON */ 248 writel(reg, cpucfg_base + CPUCFG_CX_RST_CTRL(cluster)); 249 250 return 0; 251 } 252 253 static int sunxi_cluster_powerup(unsigned int cluster) 254 { 255 u32 reg; 256 257 pr_debug("%s: cluster %u\n", __func__, cluster); 258 if (cluster >= SUNXI_NR_CLUSTERS) 259 return -EINVAL; 260 261 /* For A83T, assert cluster cores resets */ 262 if (is_a83t) { 263 reg = readl(cpucfg_base + CPUCFG_CX_RST_CTRL(cluster)); 264 reg &= ~CPUCFG_CX_RST_CTRL_CORE_RST_ALL; /* Core Reset */ 265 writel(reg, cpucfg_base + CPUCFG_CX_RST_CTRL(cluster)); 266 udelay(10); 267 } 268 269 /* assert ACINACTM */ 270 reg = readl(cpucfg_base + CPUCFG_CX_CTRL_REG1(cluster)); 271 reg |= CPUCFG_CX_CTRL_REG1_ACINACTM; 272 writel(reg, cpucfg_base + CPUCFG_CX_CTRL_REG1(cluster)); 273 274 /* assert cluster processor power-on resets */ 275 reg = readl(prcm_base + PRCM_CPU_PO_RST_CTRL(cluster)); 276 reg &= ~PRCM_CPU_PO_RST_CTRL_CORE_ALL; 277 writel(reg, prcm_base + PRCM_CPU_PO_RST_CTRL(cluster)); 278 279 /* assert cluster cores resets */ 280 if (is_a83t) { 281 reg = readl(r_cpucfg_base + 282 R_CPUCFG_CLUSTER_PO_RST_CTRL(cluster)); 283 reg &= ~CPUCFG_CX_RST_CTRL_CORE_RST_ALL; 284 writel(reg, r_cpucfg_base + 285 R_CPUCFG_CLUSTER_PO_RST_CTRL(cluster)); 286 udelay(10); 287 } 288 289 /* assert cluster resets */ 290 reg = readl(cpucfg_base + CPUCFG_CX_RST_CTRL(cluster)); 291 reg &= ~CPUCFG_CX_RST_CTRL_DBG_SOC_RST; 292 reg &= ~CPUCFG_CX_RST_CTRL_DBG_RST_ALL; 293 reg &= ~CPUCFG_CX_RST_CTRL_H_RST; 294 reg &= ~CPUCFG_CX_RST_CTRL_L2_RST; 295 296 /* 297 * Allwinner code also asserts resets for NEON on A15. According 298 * to ARM manuals, asserting power-on reset is sufficient. 299 */ 300 if (!sunxi_core_is_cortex_a15(0, cluster)) 301 reg &= ~CPUCFG_CX_RST_CTRL_ETM_RST_ALL; 302 303 writel(reg, cpucfg_base + CPUCFG_CX_RST_CTRL(cluster)); 304 305 /* hold L1/L2 reset disable signals low */ 306 reg = readl(cpucfg_base + CPUCFG_CX_CTRL_REG0(cluster)); 307 if (sunxi_core_is_cortex_a15(0, cluster)) { 308 /* Cortex-A15: hold L2RSTDISABLE low */ 309 reg &= ~CPUCFG_CX_CTRL_REG0_L2_RST_DISABLE_A15; 310 } else { 311 /* Cortex-A7: hold L1RSTDISABLE and L2RSTDISABLE low */ 312 reg &= ~CPUCFG_CX_CTRL_REG0_L1_RST_DISABLE_ALL; 313 reg &= ~CPUCFG_CX_CTRL_REG0_L2_RST_DISABLE_A7; 314 } 315 writel(reg, cpucfg_base + CPUCFG_CX_CTRL_REG0(cluster)); 316 317 /* clear cluster power gate */ 318 reg = readl(prcm_base + PRCM_PWROFF_GATING_REG(cluster)); 319 if (is_a83t) 320 reg &= ~PRCM_PWROFF_GATING_REG_CLUSTER_SUN8I; 321 else 322 reg &= ~PRCM_PWROFF_GATING_REG_CLUSTER_SUN9I; 323 writel(reg, prcm_base + PRCM_PWROFF_GATING_REG(cluster)); 324 udelay(20); 325 326 /* de-assert cluster resets */ 327 reg = readl(cpucfg_base + CPUCFG_CX_RST_CTRL(cluster)); 328 reg |= CPUCFG_CX_RST_CTRL_DBG_SOC_RST; 329 reg |= CPUCFG_CX_RST_CTRL_H_RST; 330 reg |= CPUCFG_CX_RST_CTRL_L2_RST; 331 writel(reg, cpucfg_base + CPUCFG_CX_RST_CTRL(cluster)); 332 333 /* de-assert ACINACTM */ 334 reg = readl(cpucfg_base + CPUCFG_CX_CTRL_REG1(cluster)); 335 reg &= ~CPUCFG_CX_CTRL_REG1_ACINACTM; 336 writel(reg, cpucfg_base + CPUCFG_CX_CTRL_REG1(cluster)); 337 338 return 0; 339 } 340 341 /* 342 * This bit is shared between the initial nocache_trampoline call to 343 * enable CCI-400 and proper cluster cache disable before power down. 344 */ 345 static void sunxi_cluster_cache_disable_without_axi(void) 346 { 347 if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A15) { 348 /* 349 * On the Cortex-A15 we need to disable 350 * L2 prefetching before flushing the cache. 351 */ 352 asm volatile( 353 "mcr p15, 1, %0, c15, c0, 3\n" 354 "isb\n" 355 "dsb" 356 : : "r" (0x400)); 357 } 358 359 /* Flush all cache levels for this cluster. */ 360 v7_exit_coherency_flush(all); 361 362 /* 363 * Disable cluster-level coherency by masking 364 * incoming snoops and DVM messages: 365 */ 366 cci_disable_port_by_cpu(read_cpuid_mpidr()); 367 } 368 369 static int sunxi_mc_smp_cpu_table[SUNXI_NR_CLUSTERS][SUNXI_CPUS_PER_CLUSTER]; 370 int sunxi_mc_smp_first_comer; 371 372 static DEFINE_SPINLOCK(boot_lock); 373 374 static bool sunxi_mc_smp_cluster_is_down(unsigned int cluster) 375 { 376 int i; 377 378 for (i = 0; i < SUNXI_CPUS_PER_CLUSTER; i++) 379 if (sunxi_mc_smp_cpu_table[cluster][i]) 380 return false; 381 return true; 382 } 383 384 static void sunxi_mc_smp_secondary_init(unsigned int cpu) 385 { 386 /* Clear hotplug support magic flags for cpu0 */ 387 if (cpu == 0) 388 sunxi_cpu0_hotplug_support_set(false); 389 } 390 391 static int sunxi_mc_smp_boot_secondary(unsigned int l_cpu, struct task_struct *idle) 392 { 393 unsigned int mpidr, cpu, cluster; 394 395 mpidr = cpu_logical_map(l_cpu); 396 cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0); 397 cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1); 398 399 if (!cpucfg_base) 400 return -ENODEV; 401 if (cluster >= SUNXI_NR_CLUSTERS || cpu >= SUNXI_CPUS_PER_CLUSTER) 402 return -EINVAL; 403 404 spin_lock_irq(&boot_lock); 405 406 if (sunxi_mc_smp_cpu_table[cluster][cpu]) 407 goto out; 408 409 if (sunxi_mc_smp_cluster_is_down(cluster)) { 410 sunxi_mc_smp_first_comer = true; 411 sunxi_cluster_powerup(cluster); 412 } else { 413 sunxi_mc_smp_first_comer = false; 414 } 415 416 /* This is read by incoming CPUs with their cache and MMU disabled */ 417 sync_cache_w(&sunxi_mc_smp_first_comer); 418 sunxi_cpu_powerup(cpu, cluster); 419 420 out: 421 sunxi_mc_smp_cpu_table[cluster][cpu]++; 422 spin_unlock_irq(&boot_lock); 423 424 return 0; 425 } 426 427 #ifdef CONFIG_HOTPLUG_CPU 428 static void sunxi_cluster_cache_disable(void) 429 { 430 unsigned int cluster = MPIDR_AFFINITY_LEVEL(read_cpuid_mpidr(), 1); 431 u32 reg; 432 433 pr_debug("%s: cluster %u\n", __func__, cluster); 434 435 sunxi_cluster_cache_disable_without_axi(); 436 437 /* last man standing, assert ACINACTM */ 438 reg = readl(cpucfg_base + CPUCFG_CX_CTRL_REG1(cluster)); 439 reg |= CPUCFG_CX_CTRL_REG1_ACINACTM; 440 writel(reg, cpucfg_base + CPUCFG_CX_CTRL_REG1(cluster)); 441 } 442 443 static void sunxi_mc_smp_cpu_die(unsigned int l_cpu) 444 { 445 unsigned int mpidr, cpu, cluster; 446 bool last_man; 447 448 mpidr = cpu_logical_map(l_cpu); 449 cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0); 450 cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1); 451 pr_debug("%s: cluster %u cpu %u\n", __func__, cluster, cpu); 452 453 spin_lock(&boot_lock); 454 sunxi_mc_smp_cpu_table[cluster][cpu]--; 455 if (sunxi_mc_smp_cpu_table[cluster][cpu] == 1) { 456 /* A power_up request went ahead of us. */ 457 pr_debug("%s: aborting due to a power up request\n", 458 __func__); 459 spin_unlock(&boot_lock); 460 return; 461 } else if (sunxi_mc_smp_cpu_table[cluster][cpu] > 1) { 462 pr_err("Cluster %d CPU%d boots multiple times\n", 463 cluster, cpu); 464 BUG(); 465 } 466 467 last_man = sunxi_mc_smp_cluster_is_down(cluster); 468 spin_unlock(&boot_lock); 469 470 gic_cpu_if_down(0); 471 if (last_man) 472 sunxi_cluster_cache_disable(); 473 else 474 v7_exit_coherency_flush(louis); 475 476 for (;;) 477 wfi(); 478 } 479 480 static int sunxi_cpu_powerdown(unsigned int cpu, unsigned int cluster) 481 { 482 u32 reg; 483 int gating_bit = cpu; 484 485 pr_debug("%s: cluster %u cpu %u\n", __func__, cluster, cpu); 486 if (cpu >= SUNXI_CPUS_PER_CLUSTER || cluster >= SUNXI_NR_CLUSTERS) 487 return -EINVAL; 488 489 if (is_a83t && cpu == 0) 490 gating_bit = 4; 491 492 /* gate processor power */ 493 reg = readl(prcm_base + PRCM_PWROFF_GATING_REG(cluster)); 494 reg |= PRCM_PWROFF_GATING_REG_CORE(gating_bit); 495 writel(reg, prcm_base + PRCM_PWROFF_GATING_REG(cluster)); 496 udelay(20); 497 498 /* close power switch */ 499 sunxi_cpu_power_switch_set(cpu, cluster, false); 500 501 return 0; 502 } 503 504 static int sunxi_cluster_powerdown(unsigned int cluster) 505 { 506 u32 reg; 507 508 pr_debug("%s: cluster %u\n", __func__, cluster); 509 if (cluster >= SUNXI_NR_CLUSTERS) 510 return -EINVAL; 511 512 /* assert cluster resets or system will hang */ 513 pr_debug("%s: assert cluster reset\n", __func__); 514 reg = readl(cpucfg_base + CPUCFG_CX_RST_CTRL(cluster)); 515 reg &= ~CPUCFG_CX_RST_CTRL_DBG_SOC_RST; 516 reg &= ~CPUCFG_CX_RST_CTRL_H_RST; 517 reg &= ~CPUCFG_CX_RST_CTRL_L2_RST; 518 writel(reg, cpucfg_base + CPUCFG_CX_RST_CTRL(cluster)); 519 520 /* gate cluster power */ 521 pr_debug("%s: gate cluster power\n", __func__); 522 reg = readl(prcm_base + PRCM_PWROFF_GATING_REG(cluster)); 523 if (is_a83t) 524 reg |= PRCM_PWROFF_GATING_REG_CLUSTER_SUN8I; 525 else 526 reg |= PRCM_PWROFF_GATING_REG_CLUSTER_SUN9I; 527 writel(reg, prcm_base + PRCM_PWROFF_GATING_REG(cluster)); 528 udelay(20); 529 530 return 0; 531 } 532 533 static int sunxi_mc_smp_cpu_kill(unsigned int l_cpu) 534 { 535 unsigned int mpidr, cpu, cluster; 536 unsigned int tries, count; 537 int ret = 0; 538 u32 reg; 539 540 mpidr = cpu_logical_map(l_cpu); 541 cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0); 542 cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1); 543 544 /* This should never happen */ 545 if (WARN_ON(cluster >= SUNXI_NR_CLUSTERS || 546 cpu >= SUNXI_CPUS_PER_CLUSTER)) 547 return 0; 548 549 /* wait for CPU core to die and enter WFI */ 550 count = TIMEOUT_USEC / POLL_USEC; 551 spin_lock_irq(&boot_lock); 552 for (tries = 0; tries < count; tries++) { 553 spin_unlock_irq(&boot_lock); 554 usleep_range(POLL_USEC / 2, POLL_USEC); 555 spin_lock_irq(&boot_lock); 556 557 /* 558 * If the user turns off a bunch of cores at the same 559 * time, the kernel might call cpu_kill before some of 560 * them are ready. This is because boot_lock serializes 561 * both cpu_die and cpu_kill callbacks. Either one could 562 * run first. We should wait for cpu_die to complete. 563 */ 564 if (sunxi_mc_smp_cpu_table[cluster][cpu]) 565 continue; 566 567 reg = readl(cpucfg_base + CPUCFG_CX_STATUS(cluster)); 568 if (reg & CPUCFG_CX_STATUS_STANDBYWFI(cpu)) 569 break; 570 } 571 572 if (tries >= count) { 573 ret = ETIMEDOUT; 574 goto out; 575 } 576 577 /* power down CPU core */ 578 sunxi_cpu_powerdown(cpu, cluster); 579 580 if (!sunxi_mc_smp_cluster_is_down(cluster)) 581 goto out; 582 583 /* wait for cluster L2 WFI */ 584 ret = readl_poll_timeout(cpucfg_base + CPUCFG_CX_STATUS(cluster), reg, 585 reg & CPUCFG_CX_STATUS_STANDBYWFIL2, 586 POLL_USEC, TIMEOUT_USEC); 587 if (ret) { 588 /* 589 * Ignore timeout on the cluster. Leaving the cluster on 590 * will not affect system execution, just use a bit more 591 * power. But returning an error here will only confuse 592 * the user as the CPU has already been shutdown. 593 */ 594 ret = 0; 595 goto out; 596 } 597 598 /* Power down cluster */ 599 sunxi_cluster_powerdown(cluster); 600 601 out: 602 spin_unlock_irq(&boot_lock); 603 pr_debug("%s: cluster %u cpu %u powerdown: %d\n", 604 __func__, cluster, cpu, ret); 605 return !ret; 606 } 607 608 static bool sunxi_mc_smp_cpu_can_disable(unsigned int cpu) 609 { 610 /* CPU0 hotplug not handled for sun8i-a83t */ 611 if (is_a83t) 612 if (cpu == 0) 613 return false; 614 return true; 615 } 616 #endif 617 618 static const struct smp_operations sunxi_mc_smp_smp_ops __initconst = { 619 .smp_secondary_init = sunxi_mc_smp_secondary_init, 620 .smp_boot_secondary = sunxi_mc_smp_boot_secondary, 621 #ifdef CONFIG_HOTPLUG_CPU 622 .cpu_die = sunxi_mc_smp_cpu_die, 623 .cpu_kill = sunxi_mc_smp_cpu_kill, 624 .cpu_can_disable = sunxi_mc_smp_cpu_can_disable, 625 #endif 626 }; 627 628 static bool __init sunxi_mc_smp_cpu_table_init(void) 629 { 630 unsigned int mpidr, cpu, cluster; 631 632 mpidr = read_cpuid_mpidr(); 633 cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0); 634 cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1); 635 636 if (cluster >= SUNXI_NR_CLUSTERS || cpu >= SUNXI_CPUS_PER_CLUSTER) { 637 pr_err("%s: boot CPU is out of bounds!\n", __func__); 638 return false; 639 } 640 sunxi_mc_smp_cpu_table[cluster][cpu] = 1; 641 return true; 642 } 643 644 /* 645 * Adapted from arch/arm/common/mc_smp_entry.c 646 * 647 * We need the trampoline code to enable CCI-400 on the first cluster 648 */ 649 typedef typeof(cpu_reset) phys_reset_t; 650 651 static int __init nocache_trampoline(unsigned long __unused) 652 { 653 phys_reset_t phys_reset; 654 655 setup_mm_for_reboot(); 656 sunxi_cluster_cache_disable_without_axi(); 657 658 phys_reset = (phys_reset_t)(unsigned long)__pa_symbol(cpu_reset); 659 phys_reset(__pa_symbol(sunxi_mc_smp_resume), false); 660 BUG(); 661 } 662 663 static int __init sunxi_mc_smp_loopback(void) 664 { 665 int ret; 666 667 /* 668 * We're going to soft-restart the current CPU through the 669 * low-level MCPM code by leveraging the suspend/resume 670 * infrastructure. Let's play it safe by using cpu_pm_enter() 671 * in case the CPU init code path resets the VFP or similar. 672 */ 673 sunxi_mc_smp_first_comer = true; 674 local_irq_disable(); 675 local_fiq_disable(); 676 ret = cpu_pm_enter(); 677 if (!ret) { 678 ret = cpu_suspend(0, nocache_trampoline); 679 cpu_pm_exit(); 680 } 681 local_fiq_enable(); 682 local_irq_enable(); 683 sunxi_mc_smp_first_comer = false; 684 685 return ret; 686 } 687 688 /* 689 * This holds any device nodes that we requested resources for, 690 * so that we may easily release resources in the error path. 691 */ 692 struct sunxi_mc_smp_nodes { 693 struct device_node *prcm_node; 694 struct device_node *cpucfg_node; 695 struct device_node *sram_node; 696 struct device_node *r_cpucfg_node; 697 }; 698 699 /* This structure holds SoC-specific bits tied to an enable-method string. */ 700 struct sunxi_mc_smp_data { 701 const char *enable_method; 702 int (*get_smp_nodes)(struct sunxi_mc_smp_nodes *nodes); 703 bool is_a83t; 704 }; 705 706 static void __init sunxi_mc_smp_put_nodes(struct sunxi_mc_smp_nodes *nodes) 707 { 708 of_node_put(nodes->prcm_node); 709 of_node_put(nodes->cpucfg_node); 710 of_node_put(nodes->sram_node); 711 of_node_put(nodes->r_cpucfg_node); 712 memset(nodes, 0, sizeof(*nodes)); 713 } 714 715 static int __init sun9i_a80_get_smp_nodes(struct sunxi_mc_smp_nodes *nodes) 716 { 717 nodes->prcm_node = of_find_compatible_node(NULL, NULL, 718 "allwinner,sun9i-a80-prcm"); 719 if (!nodes->prcm_node) { 720 pr_err("%s: PRCM not available\n", __func__); 721 return -ENODEV; 722 } 723 724 nodes->cpucfg_node = of_find_compatible_node(NULL, NULL, 725 "allwinner,sun9i-a80-cpucfg"); 726 if (!nodes->cpucfg_node) { 727 pr_err("%s: CPUCFG not available\n", __func__); 728 return -ENODEV; 729 } 730 731 nodes->sram_node = of_find_compatible_node(NULL, NULL, 732 "allwinner,sun9i-a80-smp-sram"); 733 if (!nodes->sram_node) { 734 pr_err("%s: Secure SRAM not available\n", __func__); 735 return -ENODEV; 736 } 737 738 return 0; 739 } 740 741 static int __init sun8i_a83t_get_smp_nodes(struct sunxi_mc_smp_nodes *nodes) 742 { 743 nodes->prcm_node = of_find_compatible_node(NULL, NULL, 744 "allwinner,sun8i-a83t-r-ccu"); 745 if (!nodes->prcm_node) { 746 pr_err("%s: PRCM not available\n", __func__); 747 return -ENODEV; 748 } 749 750 nodes->cpucfg_node = of_find_compatible_node(NULL, NULL, 751 "allwinner,sun8i-a83t-cpucfg"); 752 if (!nodes->cpucfg_node) { 753 pr_err("%s: CPUCFG not available\n", __func__); 754 return -ENODEV; 755 } 756 757 nodes->r_cpucfg_node = of_find_compatible_node(NULL, NULL, 758 "allwinner,sun8i-a83t-r-cpucfg"); 759 if (!nodes->r_cpucfg_node) { 760 pr_err("%s: RCPUCFG not available\n", __func__); 761 return -ENODEV; 762 } 763 764 return 0; 765 } 766 767 static const struct sunxi_mc_smp_data sunxi_mc_smp_data[] __initconst = { 768 { 769 .enable_method = "allwinner,sun9i-a80-smp", 770 .get_smp_nodes = sun9i_a80_get_smp_nodes, 771 }, 772 { 773 .enable_method = "allwinner,sun8i-a83t-smp", 774 .get_smp_nodes = sun8i_a83t_get_smp_nodes, 775 .is_a83t = true, 776 }, 777 }; 778 779 static int __init sunxi_mc_smp_init(void) 780 { 781 struct sunxi_mc_smp_nodes nodes = { 0 }; 782 struct device_node *node; 783 struct resource res; 784 void __iomem *addr; 785 int i, ret; 786 787 /* 788 * Don't bother checking the "cpus" node, as an enable-method 789 * property in that node is undocumented. 790 */ 791 node = of_cpu_device_node_get(0); 792 if (!node) 793 return -ENODEV; 794 795 /* 796 * We can't actually use the enable-method magic in the kernel. 797 * Our loopback / trampoline code uses the CPU suspend framework, 798 * which requires the identity mapping be available. It would not 799 * yet be available if we used the .init_cpus or .prepare_cpus 800 * callbacks in smp_operations, which we would use if we were to 801 * use CPU_METHOD_OF_DECLARE 802 */ 803 for (i = 0; i < ARRAY_SIZE(sunxi_mc_smp_data); i++) { 804 ret = of_property_match_string(node, "enable-method", 805 sunxi_mc_smp_data[i].enable_method); 806 if (!ret) 807 break; 808 } 809 810 is_a83t = sunxi_mc_smp_data[i].is_a83t; 811 812 of_node_put(node); 813 if (ret) 814 return -ENODEV; 815 816 if (!sunxi_mc_smp_cpu_table_init()) 817 return -EINVAL; 818 819 if (!cci_probed()) { 820 pr_err("%s: CCI-400 not available\n", __func__); 821 return -ENODEV; 822 } 823 824 /* Get needed device tree nodes */ 825 ret = sunxi_mc_smp_data[i].get_smp_nodes(&nodes); 826 if (ret) 827 goto err_put_nodes; 828 829 /* 830 * Unfortunately we can not request the I/O region for the PRCM. 831 * It is shared with the PRCM clock. 832 */ 833 prcm_base = of_iomap(nodes.prcm_node, 0); 834 if (!prcm_base) { 835 pr_err("%s: failed to map PRCM registers\n", __func__); 836 ret = -ENOMEM; 837 goto err_put_nodes; 838 } 839 840 cpucfg_base = of_io_request_and_map(nodes.cpucfg_node, 0, 841 "sunxi-mc-smp"); 842 if (IS_ERR(cpucfg_base)) { 843 ret = PTR_ERR(cpucfg_base); 844 pr_err("%s: failed to map CPUCFG registers: %d\n", 845 __func__, ret); 846 goto err_unmap_prcm; 847 } 848 849 if (is_a83t) { 850 r_cpucfg_base = of_io_request_and_map(nodes.r_cpucfg_node, 851 0, "sunxi-mc-smp"); 852 if (IS_ERR(r_cpucfg_base)) { 853 ret = PTR_ERR(r_cpucfg_base); 854 pr_err("%s: failed to map R-CPUCFG registers\n", 855 __func__); 856 goto err_unmap_release_cpucfg; 857 } 858 } else { 859 sram_b_smp_base = of_io_request_and_map(nodes.sram_node, 0, 860 "sunxi-mc-smp"); 861 if (IS_ERR(sram_b_smp_base)) { 862 ret = PTR_ERR(sram_b_smp_base); 863 pr_err("%s: failed to map secure SRAM\n", __func__); 864 goto err_unmap_release_cpucfg; 865 } 866 } 867 868 /* Configure CCI-400 for boot cluster */ 869 ret = sunxi_mc_smp_loopback(); 870 if (ret) { 871 pr_err("%s: failed to configure boot cluster: %d\n", 872 __func__, ret); 873 goto err_unmap_release_sram_rcpucfg; 874 } 875 876 /* We don't need the device nodes anymore */ 877 sunxi_mc_smp_put_nodes(&nodes); 878 879 /* Set the hardware entry point address */ 880 if (is_a83t) 881 addr = r_cpucfg_base + R_CPUCFG_CPU_SOFT_ENTRY_REG; 882 else 883 addr = prcm_base + PRCM_CPU_SOFT_ENTRY_REG; 884 writel(__pa_symbol(sunxi_mc_smp_secondary_startup), addr); 885 886 /* Actually enable multi cluster SMP */ 887 smp_set_ops(&sunxi_mc_smp_smp_ops); 888 889 pr_info("sunxi multi cluster SMP support installed\n"); 890 891 return 0; 892 893 err_unmap_release_sram_rcpucfg: 894 if (is_a83t) { 895 iounmap(r_cpucfg_base); 896 of_address_to_resource(nodes.r_cpucfg_node, 0, &res); 897 } else { 898 iounmap(sram_b_smp_base); 899 of_address_to_resource(nodes.sram_node, 0, &res); 900 } 901 release_mem_region(res.start, resource_size(&res)); 902 err_unmap_release_cpucfg: 903 iounmap(cpucfg_base); 904 of_address_to_resource(nodes.cpucfg_node, 0, &res); 905 release_mem_region(res.start, resource_size(&res)); 906 err_unmap_prcm: 907 iounmap(prcm_base); 908 err_put_nodes: 909 sunxi_mc_smp_put_nodes(&nodes); 910 return ret; 911 } 912 913 early_initcall(sunxi_mc_smp_init); 914