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
sunxi_core_is_cortex_a15(unsigned int core,unsigned int cluster)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
sunxi_cpu_power_switch_set(unsigned int cpu,unsigned int cluster,bool enable)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
sunxi_cpu0_hotplug_support_set(bool enable)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
sunxi_cpu_powerup(unsigned int cpu,unsigned int cluster)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
sunxi_cluster_powerup(unsigned int cluster)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 */
sunxi_cluster_cache_disable_without_axi(void)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
sunxi_mc_smp_cluster_is_down(unsigned int cluster)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
sunxi_mc_smp_secondary_init(unsigned int cpu)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
sunxi_mc_smp_boot_secondary(unsigned int l_cpu,struct task_struct * idle)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
sunxi_cluster_cache_disable(void)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
sunxi_mc_smp_cpu_die(unsigned int l_cpu)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
sunxi_cpu_powerdown(unsigned int cpu,unsigned int cluster)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
sunxi_cluster_powerdown(unsigned int cluster)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
sunxi_mc_smp_cpu_kill(unsigned int l_cpu)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
sunxi_mc_smp_cpu_can_disable(unsigned int cpu)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
sunxi_mc_smp_cpu_table_init(void)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
nocache_trampoline(unsigned long __unused)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
sunxi_mc_smp_loopback(void)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
sunxi_mc_smp_put_nodes(struct sunxi_mc_smp_nodes * nodes)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
sun9i_a80_get_smp_nodes(struct sunxi_mc_smp_nodes * nodes)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
sun8i_a83t_get_smp_nodes(struct sunxi_mc_smp_nodes * nodes)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
sunxi_mc_smp_init(void)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 >= 0)
807 break;
808 }
809
810 of_node_put(node);
811 if (ret < 0)
812 return -ENODEV;
813
814 is_a83t = sunxi_mc_smp_data[i].is_a83t;
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