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cpu_fdt.c revision 1.21 
      1 /* $NetBSD: cpu_fdt.c,v 1.21 2019/01/19 20:56:03 jmcneill Exp $ */
      2 
      3 /*-
      4  * Copyright (c) 2017 Jared McNeill <jmcneill (at) invisible.ca>
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  *
     16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
     21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
     22  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
     23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
     24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     26  * SUCH DAMAGE.
     27  */
     28 
     29 #include "opt_multiprocessor.h"
     30 #include "psci_fdt.h"
     31 
     32 #include <sys/cdefs.h>
     33 __KERNEL_RCSID(0, "$NetBSD: cpu_fdt.c,v 1.21 2019/01/19 20:56:03 jmcneill Exp $");
     34 
     35 #include <sys/param.h>
     36 #include <sys/atomic.h>
     37 #include <sys/bus.h>
     38 #include <sys/device.h>
     39 #include <sys/lwp.h>
     40 #include <sys/systm.h>
     41 #include <sys/kernel.h>
     42 
     43 #include <dev/fdt/fdtvar.h>
     44 
     45 #include <arm/armreg.h>
     46 #include <arm/cpu.h>
     47 #include <arm/cpufunc.h>
     48 #include <arm/locore.h>
     49 
     50 #include <arm/arm/psci.h>
     51 #include <arm/fdt/arm_fdtvar.h>
     52 #include <arm/fdt/psci_fdtvar.h>
     53 
     54 #include <uvm/uvm_extern.h>
     55 
     56 static int	cpu_fdt_match(device_t, cfdata_t, void *);
     57 static void	cpu_fdt_attach(device_t, device_t, void *);
     58 
     59 enum cpu_fdt_type {
     60 	ARM_CPU_UP = 1,
     61 	ARM_CPU_ARMV7,
     62 	ARM_CPU_ARMV8,
     63 };
     64 
     65 struct cpu_fdt_softc {
     66 	device_t		sc_dev;
     67 	int			sc_phandle;
     68 };
     69 
     70 static const struct of_compat_data compat_data[] = {
     71 	{ "arm,arm1176jzf-s",		ARM_CPU_UP },
     72 
     73 	{ "arm,arm-v7",			ARM_CPU_ARMV7 },
     74 	{ "arm,cortex-a5",		ARM_CPU_ARMV7 },
     75 	{ "arm,cortex-a7",		ARM_CPU_ARMV7 },
     76 	{ "arm,cortex-a8",		ARM_CPU_ARMV7 },
     77 	{ "arm,cortex-a9",		ARM_CPU_ARMV7 },
     78 	{ "arm,cortex-a12",		ARM_CPU_ARMV7 },
     79 	{ "arm,cortex-a15",		ARM_CPU_ARMV7 },
     80 	{ "arm,cortex-a17",		ARM_CPU_ARMV7 },
     81 
     82 	{ "arm,armv8",			ARM_CPU_ARMV8 },
     83 	{ "arm,cortex-a53",		ARM_CPU_ARMV8 },
     84 	{ "arm,cortex-a57",		ARM_CPU_ARMV8 },
     85 	{ "arm,cortex-a72",		ARM_CPU_ARMV8 },
     86 	{ "arm,cortex-a73",		ARM_CPU_ARMV8 },
     87 
     88 	{ NULL }
     89 };
     90 
     91 CFATTACH_DECL_NEW(cpu_fdt, sizeof(struct cpu_fdt_softc),
     92 	cpu_fdt_match, cpu_fdt_attach, NULL, NULL);
     93 
     94 static int
     95 cpu_fdt_match(device_t parent, cfdata_t cf, void *aux)
     96 {
     97 	struct fdt_attach_args * const faa = aux;
     98 	const int phandle = faa->faa_phandle;
     99 	enum cpu_fdt_type type;
    100 	int is_compatible;
    101 	bus_addr_t mpidr;
    102 
    103 	is_compatible = of_match_compat_data(phandle, compat_data);
    104 	if (!is_compatible)
    105 		return 0;
    106 
    107 	type = of_search_compatible(phandle, compat_data)->data;
    108 	switch (type) {
    109 	case ARM_CPU_ARMV7:
    110 	case ARM_CPU_ARMV8:
    111 		if (fdtbus_get_reg(phandle, 0, &mpidr, NULL) != 0)
    112 			return 0;
    113 	default:
    114 		break;
    115 	}
    116 
    117 	return is_compatible;
    118 }
    119 
    120 static void
    121 cpu_fdt_attach(device_t parent, device_t self, void *aux)
    122 {
    123 	struct cpu_fdt_softc * const sc = device_private(self);
    124 	struct fdt_attach_args * const faa = aux;
    125 	const int phandle = faa->faa_phandle;
    126 	enum cpu_fdt_type type;
    127 	bus_addr_t mpidr;
    128 	cpuid_t cpuid;
    129 
    130 	sc->sc_dev = self;
    131 	sc->sc_phandle = phandle;
    132 
    133 	type = of_search_compatible(phandle, compat_data)->data;
    134 
    135 	switch (type) {
    136 	case ARM_CPU_ARMV7:
    137 	case ARM_CPU_ARMV8:
    138 		if (fdtbus_get_reg(phandle, 0, &mpidr, NULL) != 0) {
    139 			aprint_error(": missing 'reg' property\n");
    140 			return;
    141 		}
    142 		cpuid = mpidr;
    143 		break;
    144 	default:
    145 		cpuid = 0;
    146 		break;
    147 	}
    148 
    149 	/* Attach the CPU */
    150 	cpu_attach(self, cpuid);
    151 
    152 	/* Attach CPU frequency scaling provider */
    153 	config_found(self, faa, NULL);
    154 }
    155 
    156 #ifdef MULTIPROCESSOR
    157 static register_t
    158 cpu_fdt_mpstart_pa(void)
    159 {
    160 	bool ok __diagused;
    161 	paddr_t pa;
    162 
    163 	ok = pmap_extract(pmap_kernel(), (vaddr_t)cpu_mpstart, &pa);
    164 	KASSERT(ok);
    165 
    166 	return pa;
    167 }
    168 
    169 static int
    170 spintable_cpu_on(u_int cpuindex, paddr_t entry_point_address, paddr_t cpu_release_addr)
    171 {
    172 	/*
    173 	 * we need devmap for cpu-release-addr in advance.
    174 	 * __HAVE_MM_MD_DIRECT_MAPPED_PHYS nor pmap didn't work at this point.
    175 	 */
    176 	if (pmap_devmap_find_pa(cpu_release_addr, sizeof(paddr_t)) == NULL) {
    177 		aprint_error("%s: devmap for cpu-release-addr"
    178 		    " 0x%08"PRIxPADDR" required\n", __func__, cpu_release_addr);
    179 		return -1;
    180 	} else {
    181 		extern struct bus_space arm_generic_bs_tag;
    182 		bus_space_handle_t ioh;
    183 
    184 		bus_space_map(&arm_generic_bs_tag, cpu_release_addr,
    185 		    sizeof(paddr_t), 0, &ioh);
    186 		bus_space_write_4(&arm_generic_bs_tag, ioh, 0,
    187 		    entry_point_address);
    188 		bus_space_unmap(&arm_generic_bs_tag, ioh, sizeof(paddr_t));
    189 	}
    190 
    191 	return 0;
    192 }
    193 #endif /* MULTIPROCESSOR */
    194 
    195 #ifdef MULTIPROCESSOR
    196 static bool
    197 arm_fdt_cpu_okay(const int child)
    198 {
    199 	const char *s;
    200 
    201 	s = fdtbus_get_string(child, "device_type");
    202 	if (!s || strcmp(s, "cpu") != 0)
    203 		return false;
    204 
    205 	s = fdtbus_get_string(child, "status");
    206 	if (s) {
    207 		if (strcmp(s, "okay") == 0)
    208 			return false;
    209 		if (strcmp(s, "disabled") == 0)
    210 			return of_hasprop(child, "enable-method");
    211 		return false;
    212 	} else {
    213 		return true;
    214 	}
    215 }
    216 #endif /* MULTIPROCESSOR */
    217 
    218 void
    219 arm_fdt_cpu_bootstrap(void)
    220 {
    221 #ifdef MULTIPROCESSOR
    222 	uint64_t mpidr, bp_mpidr;
    223 	u_int cpuindex;
    224 	int child;
    225 
    226 	const int cpus = OF_finddevice("/cpus");
    227 	if (cpus == -1) {
    228 		aprint_error("%s: no /cpus node found\n", __func__);
    229 		arm_cpu_max = 1;
    230 		return;
    231 	}
    232 
    233 	/* Count CPUs */
    234 	arm_cpu_max = 0;
    235 
    236 	/* MPIDR affinity levels of boot processor. */
    237 	bp_mpidr = cpu_mpidr_aff_read();
    238 
    239 	/* Boot APs */
    240 	cpuindex = 1;
    241 	for (child = OF_child(cpus); child; child = OF_peer(child)) {
    242 		if (!arm_fdt_cpu_okay(child))
    243 			continue;
    244 
    245 		arm_cpu_max++;
    246 		if (fdtbus_get_reg64(child, 0, &mpidr, NULL) != 0)
    247 			continue;
    248 		if (mpidr == bp_mpidr)
    249 			continue; 	/* BP already started */
    250 
    251 		KASSERT(cpuindex < MAXCPUS);
    252 		cpu_mpidr[cpuindex] = mpidr;
    253 		cpu_dcache_wb_range((vaddr_t)&cpu_mpidr[cpuindex],
    254 		    sizeof(cpu_mpidr[cpuindex]));
    255 
    256 		cpuindex++;
    257 	}
    258 #endif
    259 }
    260 
    261 #ifdef MULTIPROCESSOR
    262 static int
    263 arm_fdt_cpu_enable(int phandle, const char *method)
    264 {
    265 	__link_set_decl(arm_cpu_methods, struct arm_cpu_method);
    266 	struct arm_cpu_method * const *acm;
    267 	__link_set_foreach(acm, arm_cpu_methods) {
    268 		if (strcmp(method, (*acm)->acm_compat) == 0)
    269 			return (*acm)->acm_enable(phandle);
    270 	}
    271 	return ENOSYS;
    272 }
    273 #endif
    274 
    275 void
    276 arm_fdt_cpu_mpstart(void)
    277 {
    278 #ifdef MULTIPROCESSOR
    279 	uint64_t mpidr, bp_mpidr;
    280 	u_int cpuindex, i;
    281 	int child, error;
    282 	const char *method;
    283 
    284 	const int cpus = OF_finddevice("/cpus");
    285 	if (cpus == -1) {
    286 		aprint_error("%s: no /cpus node found\n", __func__);
    287 		return;
    288 	}
    289 
    290 	/* MPIDR affinity levels of boot processor. */
    291 	bp_mpidr = cpu_mpidr_aff_read();
    292 
    293 	/* Boot APs */
    294 	cpuindex = 1;
    295 	for (child = OF_child(cpus); child; child = OF_peer(child)) {
    296 		if (!arm_fdt_cpu_okay(child))
    297 			continue;
    298 
    299 		if (fdtbus_get_reg64(child, 0, &mpidr, NULL) != 0)
    300 			continue;
    301 
    302 		if (mpidr == bp_mpidr)
    303 			continue; 	/* BP already started */
    304 
    305 		method = fdtbus_get_string(child, "enable-method");
    306 		if (method == NULL)
    307 			method = fdtbus_get_string(cpus, "enable-method");
    308 		if (method == NULL)
    309 			continue;
    310 
    311 		error = arm_fdt_cpu_enable(child, method);
    312 		if (error != 0) {
    313 			aprint_error("%s: %s: unsupported enable-method\n", __func__, method);
    314 			continue;
    315 		}
    316 
    317 		/* Wake up AP in case firmware has placed it in WFE state */
    318 		__asm __volatile("sev" ::: "memory");
    319 
    320 		/* Wait for AP to start */
    321 		for (i = 0x10000000; i > 0; i--) {
    322 			membar_consumer();
    323 			if (arm_cpu_hatched & __BIT(cpuindex))
    324 				break;
    325 		}
    326 		if (i == 0)
    327 			aprint_error("cpu%d: WARNING: AP failed to start\n", cpuindex);
    328 
    329 		cpuindex++;
    330 	}
    331 #endif /* MULTIPROCESSOR */
    332 }
    333 
    334 static int
    335 cpu_enable_nullop(int phandle)
    336 {
    337 	return ENXIO;
    338 }
    339 ARM_CPU_METHOD(default, "", cpu_enable_nullop);
    340 
    341 #if defined(MULTIPROCESSOR) && NPSCI_FDT > 0
    342 static int
    343 cpu_enable_psci(int phandle)
    344 {
    345 	static bool psci_probed, psci_p;
    346 	uint64_t mpidr;
    347 	int ret;
    348 
    349 	if (!psci_probed) {
    350 		psci_probed = true;
    351 		psci_p = psci_fdt_preinit() == 0;
    352 	}
    353 	if (!psci_p)
    354 		return ENXIO;
    355 
    356 	fdtbus_get_reg64(phandle, 0, &mpidr, NULL);
    357 
    358 	ret = psci_cpu_on(mpidr, cpu_fdt_mpstart_pa(), 0);
    359 	if (ret != PSCI_SUCCESS)
    360 		return EIO;
    361 
    362 	return 0;
    363 }
    364 ARM_CPU_METHOD(psci, "psci", cpu_enable_psci);
    365 #endif
    366 
    367 #if defined(MULTIPROCESSOR)
    368 static int
    369 cpu_enable_spin_table(int phandle)
    370 {
    371 	uint64_t mpidr, addr;
    372 	int ret;
    373 
    374 	fdtbus_get_reg64(phandle, 0, &mpidr, NULL);
    375 
    376 	if (of_getprop_uint64(phandle, "cpu-release-addr", &addr) != 0)
    377 		return ENXIO;
    378 
    379 	ret = spintable_cpu_on(mpidr, cpu_fdt_mpstart_pa(), (paddr_t)addr);
    380 	if (ret != 0)
    381 		return EIO;
    382 
    383 	return 0;
    384 }
    385 ARM_CPU_METHOD(spin_table, "spin-table", cpu_enable_spin_table);
    386 #endif
    387