1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * OMAP4 SMP source file. It contains platform specific functions
4 * needed for the linux smp kernel.
5 *
6 * Copyright (C) 2009 Texas Instruments, Inc.
7 *
8 * Author:
9 * Santosh Shilimkar <santosh.shilimkar@ti.com>
10 *
11 * Platform file needed for the OMAP4 SMP. This file is based on arm
12 * realview smp platform.
13 * * Copyright (c) 2002 ARM Limited.
14 */
15#include <linux/init.h>
16#include <linux/device.h>
17#include <linux/smp.h>
18#include <linux/io.h>
19#include <linux/irqchip/arm-gic.h>
20
21#include <asm/sections.h>
22#include <asm/smp_scu.h>
23#include <asm/virt.h>
24
25#include "omap-secure.h"
26#include "omap-wakeupgen.h"
27#include <asm/cputype.h>
28
29#include "soc.h"
30#include "iomap.h"
31#include "common.h"
32#include "clockdomain.h"
33#include "pm.h"
34
35#define CPU_MASK 0xff0ffff0
36#define CPU_CORTEX_A9 0x410FC090
37#define CPU_CORTEX_A15 0x410FC0F0
38
39#define OMAP5_CORE_COUNT 0x2
40
41#define AUX_CORE_BOOT0_GP_RELEASE 0x020
42#define AUX_CORE_BOOT0_HS_RELEASE 0x200
43
44struct omap_smp_config {
45 unsigned long cpu1_rstctrl_pa;
46 void __iomem *cpu1_rstctrl_va;
47 void __iomem *scu_base;
48 void __iomem *wakeupgen_base;
49 void *startup_addr;
50};
51
52static struct omap_smp_config cfg;
53
54static const struct omap_smp_config omap443x_cfg __initconst = {
55 .cpu1_rstctrl_pa = 0x4824380c,
56 .startup_addr = omap4_secondary_startup,
57};
58
59static const struct omap_smp_config omap446x_cfg __initconst = {
60 .cpu1_rstctrl_pa = 0x4824380c,
61 .startup_addr = omap4460_secondary_startup,
62};
63
64static const struct omap_smp_config omap5_cfg __initconst = {
65 .cpu1_rstctrl_pa = 0x48243810,
66 .startup_addr = omap5_secondary_startup,
67};
68
69void __iomem *omap4_get_scu_base(void)
70{
71 return cfg.scu_base;
72}
73
74#ifdef CONFIG_OMAP5_ERRATA_801819
75static void omap5_erratum_workaround_801819(void)
76{
77 u32 acr, revidr;
78 u32 acr_mask;
79
80 /* REVIDR[3] indicates erratum fix available on silicon */
81 asm volatile ("mrc p15, 0, %0, c0, c0, 6" : "=r" (revidr));
82 if (revidr & (0x1 << 3))
83 return;
84
85 asm volatile ("mrc p15, 0, %0, c1, c0, 1" : "=r" (acr));
86 /*
87 * BIT(27) - Disables streaming. All write-allocate lines allocate in
88 * the L1 or L2 cache.
89 * BIT(25) - Disables streaming. All write-allocate lines allocate in
90 * the L1 cache.
91 */
92 acr_mask = (0x3 << 25) | (0x3 << 27);
93 /* do we already have it done.. if yes, skip expensive smc */
94 if ((acr & acr_mask) == acr_mask)
95 return;
96
97 acr |= acr_mask;
98 omap_smc1(OMAP5_DRA7_MON_SET_ACR_INDEX, acr);
99
100 pr_debug("%s: ARM erratum workaround 801819 applied on CPU%d\n",
101 __func__, smp_processor_id());
102}
103#else
104static inline void omap5_erratum_workaround_801819(void) { }
105#endif
106
107#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR
108/*
109 * Configure ACR and enable ACTLR[0] (Enable invalidates of BTB with
110 * ICIALLU) to activate the workaround for secondary Core.
111 * NOTE: it is assumed that the primary core's configuration is done
112 * by the boot loader (kernel will detect a misconfiguration and complain
113 * if this is not done).
114 *
115 * In General Purpose(GP) devices, ACR bit settings can only be done
116 * by ROM code in "secure world" using the smc call and there is no
117 * option to update the "firmware" on such devices. This also works for
118 * High security(HS) devices, as a backup option in case the
119 * "update" is not done in the "security firmware".
120 */
121static void omap5_secondary_harden_predictor(void)
122{
123 u32 acr, acr_mask;
124
125 asm volatile ("mrc p15, 0, %0, c1, c0, 1" : "=r" (acr));
126
127 /*
128 * ACTLR[0] (Enable invalidates of BTB with ICIALLU)
129 */
130 acr_mask = BIT(0);
131
132 /* Do we already have it done.. if yes, skip expensive smc */
133 if ((acr & acr_mask) == acr_mask)
134 return;
135
136 acr |= acr_mask;
137 omap_smc1(OMAP5_DRA7_MON_SET_ACR_INDEX, acr);
138
139 pr_debug("%s: ARM ACR setup for CVE_2017_5715 applied on CPU%d\n",
140 __func__, smp_processor_id());
141}
142#else
143static inline void omap5_secondary_harden_predictor(void) { }
144#endif
145
146static void omap4_secondary_init(unsigned int cpu)
147{
148 /*
149 * Configure ACTRL and enable NS SMP bit access on CPU1 on HS device.
150 * OMAP44XX EMU/HS devices - CPU0 SMP bit access is enabled in PPA
151 * init and for CPU1, a secure PPA API provided. CPU0 must be ON
152 * while executing NS_SMP API on CPU1 and PPA version must be 1.4.0+.
153 * OMAP443X GP devices- SMP bit isn't accessible.
154 * OMAP446X GP devices - SMP bit access is enabled on both CPUs.
155 */
156 if (soc_is_omap443x() && (omap_type() != OMAP2_DEVICE_TYPE_GP))
157 omap_secure_dispatcher(OMAP4_PPA_CPU_ACTRL_SMP_INDEX,
158 flag: 4, nargs: 0, arg1: 0, arg2: 0, arg3: 0, arg4: 0);
159
160 if (soc_is_omap54xx() || soc_is_dra7xx()) {
161 /*
162 * Configure the CNTFRQ register for the secondary cpu's which
163 * indicates the frequency of the cpu local timers.
164 */
165 set_cntfreq();
166 /* Configure ACR to disable streaming WA for 801819 */
167 omap5_erratum_workaround_801819();
168 /* Enable ACR to allow for ICUALLU workaround */
169 omap5_secondary_harden_predictor();
170 }
171}
172
173static int omap4_boot_secondary(unsigned int cpu, struct task_struct *idle)
174{
175 static struct clockdomain *cpu1_clkdm;
176 static bool booted;
177 static struct powerdomain *cpu1_pwrdm;
178
179 /*
180 * Update the AuxCoreBoot0 with boot state for secondary core.
181 * omap4_secondary_startup() routine will hold the secondary core till
182 * the AuxCoreBoot1 register is updated with cpu state
183 * A barrier is added to ensure that write buffer is drained
184 */
185 if (omap_secure_apis_support())
186 omap_modify_auxcoreboot0(AUX_CORE_BOOT0_HS_RELEASE,
187 clear_mask: 0xfffffdff);
188 else
189 writel_relaxed(AUX_CORE_BOOT0_GP_RELEASE,
190 cfg.wakeupgen_base + OMAP_AUX_CORE_BOOT_0);
191
192 if (!cpu1_clkdm && !cpu1_pwrdm) {
193 cpu1_clkdm = clkdm_lookup(name: "mpu1_clkdm");
194 cpu1_pwrdm = pwrdm_lookup(name: "cpu1_pwrdm");
195 }
196
197 /*
198 * The SGI(Software Generated Interrupts) are not wakeup capable
199 * from low power states. This is known limitation on OMAP4 and
200 * needs to be worked around by using software forced clockdomain
201 * wake-up. To wakeup CPU1, CPU0 forces the CPU1 clockdomain to
202 * software force wakeup. The clockdomain is then put back to
203 * hardware supervised mode.
204 * More details can be found in OMAP4430 TRM - Version J
205 * Section :
206 * 4.3.4.2 Power States of CPU0 and CPU1
207 */
208 if (booted && cpu1_pwrdm && cpu1_clkdm) {
209 /*
210 * GIC distributor control register has changed between
211 * CortexA9 r1pX and r2pX. The Control Register secure
212 * banked version is now composed of 2 bits:
213 * bit 0 == Secure Enable
214 * bit 1 == Non-Secure Enable
215 * The Non-Secure banked register has not changed
216 * Because the ROM Code is based on the r1pX GIC, the CPU1
217 * GIC restoration will cause a problem to CPU0 Non-Secure SW.
218 * The workaround must be:
219 * 1) Before doing the CPU1 wakeup, CPU0 must disable
220 * the GIC distributor
221 * 2) CPU1 must re-enable the GIC distributor on
222 * it's wakeup path.
223 */
224 if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD)) {
225 local_irq_disable();
226 gic_dist_disable();
227 }
228
229 /*
230 * Ensure that CPU power state is set to ON to avoid CPU
231 * powerdomain transition on wfi
232 */
233 clkdm_deny_idle_nolock(clkdm: cpu1_clkdm);
234 pwrdm_set_next_pwrst(pwrdm: cpu1_pwrdm, PWRDM_POWER_ON);
235 clkdm_allow_idle_nolock(clkdm: cpu1_clkdm);
236
237 if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD)) {
238 while (gic_dist_disabled()) {
239 udelay(1);
240 cpu_relax();
241 }
242 gic_timer_retrigger();
243 local_irq_enable();
244 }
245 } else {
246 dsb_sev();
247 booted = true;
248 }
249
250 arch_send_wakeup_ipi_mask(cpumask_of(cpu));
251
252 return 0;
253}
254
255/*
256 * Initialise the CPU possible map early - this describes the CPUs
257 * which may be present or become present in the system.
258 */
259static void __init omap4_smp_init_cpus(void)
260{
261 unsigned int i = 0, ncores = 1, cpu_id;
262
263 /* Use ARM cpuid check here, as SoC detection will not work so early */
264 cpu_id = read_cpuid_id() & CPU_MASK;
265 if (cpu_id == CPU_CORTEX_A9) {
266 /*
267 * Currently we can't call ioremap here because
268 * SoC detection won't work until after init_early.
269 */
270 cfg.scu_base = OMAP2_L4_IO_ADDRESS(scu_a9_get_base());
271 BUG_ON(!cfg.scu_base);
272 ncores = scu_get_core_count(cfg.scu_base);
273 } else if (cpu_id == CPU_CORTEX_A15) {
274 ncores = OMAP5_CORE_COUNT;
275 }
276
277 /* sanity check */
278 if (ncores > nr_cpu_ids) {
279 pr_warn("SMP: %u cores greater than maximum (%u), clipping\n",
280 ncores, nr_cpu_ids);
281 ncores = nr_cpu_ids;
282 }
283
284 for (i = 0; i < ncores; i++)
285 set_cpu_possible(cpu: i, possible: true);
286}
287
288/*
289 * For now, just make sure the start-up address is not within the booting
290 * kernel space as that means we just overwrote whatever secondary_startup()
291 * code there was.
292 */
293static bool __init omap4_smp_cpu1_startup_valid(unsigned long addr)
294{
295 if ((addr >= __pa(PAGE_OFFSET)) && (addr <= __pa(__bss_start)))
296 return false;
297
298 return true;
299}
300
301/*
302 * We may need to reset CPU1 before configuring, otherwise kexec boot can end
303 * up trying to use old kernel startup address or suspend-resume will
304 * occasionally fail to bring up CPU1 on 4430 if CPU1 fails to enter deeper
305 * idle states.
306 */
307static void __init omap4_smp_maybe_reset_cpu1(struct omap_smp_config *c)
308{
309 unsigned long cpu1_startup_pa, cpu1_ns_pa_addr;
310 bool needs_reset = false;
311 u32 released;
312
313 if (omap_secure_apis_support())
314 released = omap_read_auxcoreboot0() & AUX_CORE_BOOT0_HS_RELEASE;
315 else
316 released = readl_relaxed(cfg.wakeupgen_base +
317 OMAP_AUX_CORE_BOOT_0) &
318 AUX_CORE_BOOT0_GP_RELEASE;
319 if (released) {
320 pr_warn("smp: CPU1 not parked?\n");
321
322 return;
323 }
324
325 cpu1_startup_pa = readl_relaxed(cfg.wakeupgen_base +
326 OMAP_AUX_CORE_BOOT_1);
327
328 /* Did the configured secondary_startup() get overwritten? */
329 if (!omap4_smp_cpu1_startup_valid(addr: cpu1_startup_pa))
330 needs_reset = true;
331
332 /*
333 * If omap4 or 5 has NS_PA_ADDR configured, CPU1 may be in a
334 * deeper idle state in WFI and will wake to an invalid address.
335 */
336 if ((soc_is_omap44xx() || soc_is_omap54xx())) {
337 cpu1_ns_pa_addr = omap4_get_cpu1_ns_pa_addr();
338 if (!omap4_smp_cpu1_startup_valid(addr: cpu1_ns_pa_addr))
339 needs_reset = true;
340 } else {
341 cpu1_ns_pa_addr = 0;
342 }
343
344 if (!needs_reset || !c->cpu1_rstctrl_va)
345 return;
346
347 pr_info("smp: CPU1 parked within kernel, needs reset (0x%lx 0x%lx)\n",
348 cpu1_startup_pa, cpu1_ns_pa_addr);
349
350 writel_relaxed(1, c->cpu1_rstctrl_va);
351 readl_relaxed(c->cpu1_rstctrl_va);
352 writel_relaxed(0, c->cpu1_rstctrl_va);
353}
354
355static void __init omap4_smp_prepare_cpus(unsigned int max_cpus)
356{
357 const struct omap_smp_config *c = NULL;
358
359 if (soc_is_omap443x())
360 c = &omap443x_cfg;
361 else if (soc_is_omap446x())
362 c = &omap446x_cfg;
363 else if (soc_is_dra74x() || soc_is_omap54xx() || soc_is_dra76x())
364 c = &omap5_cfg;
365
366 if (!c) {
367 pr_err("%s Unknown SMP SoC?\n", __func__);
368 return;
369 }
370
371 /* Must preserve cfg.scu_base set earlier */
372 cfg.cpu1_rstctrl_pa = c->cpu1_rstctrl_pa;
373 cfg.startup_addr = c->startup_addr;
374 cfg.wakeupgen_base = omap_get_wakeupgen_base();
375
376 if (soc_is_dra74x() || soc_is_omap54xx() || soc_is_dra76x()) {
377 if ((__boot_cpu_mode & MODE_MASK) == HYP_MODE)
378 cfg.startup_addr = omap5_secondary_hyp_startup;
379 omap5_erratum_workaround_801819();
380 }
381
382 cfg.cpu1_rstctrl_va = ioremap(offset: cfg.cpu1_rstctrl_pa, size: 4);
383 if (!cfg.cpu1_rstctrl_va)
384 return;
385
386 /*
387 * Initialise the SCU and wake up the secondary core using
388 * wakeup_secondary().
389 */
390 if (cfg.scu_base)
391 scu_enable(cfg.scu_base);
392
393 omap4_smp_maybe_reset_cpu1(c: &cfg);
394
395 /*
396 * Write the address of secondary startup routine into the
397 * AuxCoreBoot1 where ROM code will jump and start executing
398 * on secondary core once out of WFE
399 * A barrier is added to ensure that write buffer is drained
400 */
401 if (omap_secure_apis_support())
402 omap_auxcoreboot_addr(__pa_symbol(cfg.startup_addr));
403 else
404 writel_relaxed(__pa_symbol(cfg.startup_addr),
405 cfg.wakeupgen_base + OMAP_AUX_CORE_BOOT_1);
406}
407
408const struct smp_operations omap4_smp_ops __initconst = {
409 .smp_init_cpus = omap4_smp_init_cpus,
410 .smp_prepare_cpus = omap4_smp_prepare_cpus,
411 .smp_secondary_init = omap4_secondary_init,
412 .smp_boot_secondary = omap4_boot_secondary,
413#ifdef CONFIG_HOTPLUG_CPU
414 .cpu_die = omap4_cpu_die,
415 .cpu_kill = omap4_cpu_kill,
416#endif
417};
418

source code of linux/arch/arm/mach-omap2/omap-smp.c