xref: /openbmc/qemu/hw/arm/raspi.c (revision 79e42085)
1 /*
2  * Raspberry Pi emulation (c) 2012 Gregory Estrade
3  * Upstreaming code cleanup [including bcm2835_*] (c) 2013 Jan Petrous
4  *
5  * Rasperry Pi 2 emulation Copyright (c) 2015, Microsoft
6  * Written by Andrew Baumann
7  *
8  * Raspberry Pi 3 emulation Copyright (c) 2018 Zoltán Baldaszti
9  * Upstream code cleanup (c) 2018 Pekka Enberg
10  *
11  * This code is licensed under the GNU GPLv2 and later.
12  */
13 
14 #include "qemu/osdep.h"
15 #include "qemu/units.h"
16 #include "qapi/error.h"
17 #include "qemu-common.h"
18 #include "cpu.h"
19 #include "hw/arm/bcm2836.h"
20 #include "qemu/error-report.h"
21 #include "hw/boards.h"
22 #include "hw/loader.h"
23 #include "hw/arm/boot.h"
24 #include "sysemu/sysemu.h"
25 
26 #define SMPBOOT_ADDR    0x300 /* this should leave enough space for ATAGS */
27 #define MVBAR_ADDR      0x400 /* secure vectors */
28 #define BOARDSETUP_ADDR (MVBAR_ADDR + 0x20) /* board setup code */
29 #define FIRMWARE_ADDR_2 0x8000 /* Pi 2 loads kernel.img here by default */
30 #define FIRMWARE_ADDR_3 0x80000 /* Pi 3 loads kernel.img here by default */
31 #define SPINTABLE_ADDR  0xd8 /* Pi 3 bootloader spintable */
32 
33 /* Table of Linux board IDs for different Pi versions */
34 static const int raspi_boardid[] = {[1] = 0xc42, [2] = 0xc43, [3] = 0xc44};
35 
36 typedef struct RasPiState {
37     BCM283XState soc;
38     MemoryRegion ram;
39 } RasPiState;
40 
41 static void write_smpboot(ARMCPU *cpu, const struct arm_boot_info *info)
42 {
43     static const uint32_t smpboot[] = {
44         0xe1a0e00f, /*    mov     lr, pc */
45         0xe3a0fe00 + (BOARDSETUP_ADDR >> 4), /* mov pc, BOARDSETUP_ADDR */
46         0xee100fb0, /*    mrc     p15, 0, r0, c0, c0, 5;get core ID */
47         0xe7e10050, /*    ubfx    r0, r0, #0, #2       ;extract LSB */
48         0xe59f5014, /*    ldr     r5, =0x400000CC      ;load mbox base */
49         0xe320f001, /* 1: yield */
50         0xe7953200, /*    ldr     r3, [r5, r0, lsl #4] ;read mbox for our core*/
51         0xe3530000, /*    cmp     r3, #0               ;spin while zero */
52         0x0afffffb, /*    beq     1b */
53         0xe7853200, /*    str     r3, [r5, r0, lsl #4] ;clear mbox */
54         0xe12fff13, /*    bx      r3                   ;jump to target */
55         0x400000cc, /* (constant: mailbox 3 read/clear base) */
56     };
57 
58     /* check that we don't overrun board setup vectors */
59     QEMU_BUILD_BUG_ON(SMPBOOT_ADDR + sizeof(smpboot) > MVBAR_ADDR);
60     /* check that board setup address is correctly relocated */
61     QEMU_BUILD_BUG_ON((BOARDSETUP_ADDR & 0xf) != 0
62                       || (BOARDSETUP_ADDR >> 4) >= 0x100);
63 
64     rom_add_blob_fixed("raspi_smpboot", smpboot, sizeof(smpboot),
65                        info->smp_loader_start);
66 }
67 
68 static void write_smpboot64(ARMCPU *cpu, const struct arm_boot_info *info)
69 {
70     /* Unlike the AArch32 version we don't need to call the board setup hook.
71      * The mechanism for doing the spin-table is also entirely different.
72      * We must have four 64-bit fields at absolute addresses
73      * 0xd8, 0xe0, 0xe8, 0xf0 in RAM, which are the flag variables for
74      * our CPUs, and which we must ensure are zero initialized before
75      * the primary CPU goes into the kernel. We put these variables inside
76      * a rom blob, so that the reset for ROM contents zeroes them for us.
77      */
78     static const uint32_t smpboot[] = {
79         0xd2801b05, /*        mov     x5, 0xd8 */
80         0xd53800a6, /*        mrs     x6, mpidr_el1 */
81         0x924004c6, /*        and     x6, x6, #0x3 */
82         0xd503205f, /* spin:  wfe */
83         0xf86678a4, /*        ldr     x4, [x5,x6,lsl #3] */
84         0xb4ffffc4, /*        cbz     x4, spin */
85         0xd2800000, /*        mov     x0, #0x0 */
86         0xd2800001, /*        mov     x1, #0x0 */
87         0xd2800002, /*        mov     x2, #0x0 */
88         0xd2800003, /*        mov     x3, #0x0 */
89         0xd61f0080, /*        br      x4 */
90     };
91 
92     static const uint64_t spintables[] = {
93         0, 0, 0, 0
94     };
95 
96     rom_add_blob_fixed("raspi_smpboot", smpboot, sizeof(smpboot),
97                        info->smp_loader_start);
98     rom_add_blob_fixed("raspi_spintables", spintables, sizeof(spintables),
99                        SPINTABLE_ADDR);
100 }
101 
102 static void write_board_setup(ARMCPU *cpu, const struct arm_boot_info *info)
103 {
104     arm_write_secure_board_setup_dummy_smc(cpu, info, MVBAR_ADDR);
105 }
106 
107 static void reset_secondary(ARMCPU *cpu, const struct arm_boot_info *info)
108 {
109     CPUState *cs = CPU(cpu);
110     cpu_set_pc(cs, info->smp_loader_start);
111 }
112 
113 static void setup_boot(MachineState *machine, int version, size_t ram_size)
114 {
115     static struct arm_boot_info binfo;
116     int r;
117 
118     binfo.board_id = raspi_boardid[version];
119     binfo.ram_size = ram_size;
120     binfo.nb_cpus = smp_cpus;
121 
122     if (version <= 2) {
123         /* The rpi1 and 2 require some custom setup code to run in Secure
124          * mode before booting a kernel (to set up the SMC vectors so
125          * that we get a no-op SMC; this is used by Linux to call the
126          * firmware for some cache maintenance operations.
127          * The rpi3 doesn't need this.
128          */
129         binfo.board_setup_addr = BOARDSETUP_ADDR;
130         binfo.write_board_setup = write_board_setup;
131         binfo.secure_board_setup = true;
132         binfo.secure_boot = true;
133     }
134 
135     /* Pi2 and Pi3 requires SMP setup */
136     if (version >= 2) {
137         binfo.smp_loader_start = SMPBOOT_ADDR;
138         if (version == 2) {
139             binfo.write_secondary_boot = write_smpboot;
140         } else {
141             binfo.write_secondary_boot = write_smpboot64;
142         }
143         binfo.secondary_cpu_reset_hook = reset_secondary;
144     }
145 
146     /* If the user specified a "firmware" image (e.g. UEFI), we bypass
147      * the normal Linux boot process
148      */
149     if (machine->firmware) {
150         hwaddr firmware_addr = version == 3 ? FIRMWARE_ADDR_3 : FIRMWARE_ADDR_2;
151         /* load the firmware image (typically kernel.img) */
152         r = load_image_targphys(machine->firmware, firmware_addr,
153                                 ram_size - firmware_addr);
154         if (r < 0) {
155             error_report("Failed to load firmware from %s", machine->firmware);
156             exit(1);
157         }
158 
159         binfo.entry = firmware_addr;
160         binfo.firmware_loaded = true;
161     } else {
162         binfo.kernel_filename = machine->kernel_filename;
163         binfo.kernel_cmdline = machine->kernel_cmdline;
164         binfo.initrd_filename = machine->initrd_filename;
165     }
166 
167     arm_load_kernel(ARM_CPU(first_cpu), &binfo);
168 }
169 
170 static void raspi_init(MachineState *machine, int version)
171 {
172     RasPiState *s = g_new0(RasPiState, 1);
173     uint32_t vcram_size;
174     DriveInfo *di;
175     BlockBackend *blk;
176     BusState *bus;
177     DeviceState *carddev;
178 
179     if (machine->ram_size > 1 * GiB) {
180         error_report("Requested ram size is too large for this machine: "
181                      "maximum is 1GB");
182         exit(1);
183     }
184 
185     object_initialize_child(OBJECT(machine), "soc", &s->soc, sizeof(s->soc),
186                             version == 3 ? TYPE_BCM2837 : TYPE_BCM2836,
187                             &error_abort, NULL);
188 
189     /* Allocate and map RAM */
190     memory_region_allocate_system_memory(&s->ram, OBJECT(machine), "ram",
191                                          machine->ram_size);
192     /* FIXME: Remove when we have custom CPU address space support */
193     memory_region_add_subregion_overlap(get_system_memory(), 0, &s->ram, 0);
194 
195     /* Setup the SOC */
196     object_property_add_const_link(OBJECT(&s->soc), "ram", OBJECT(&s->ram),
197                                    &error_abort);
198     object_property_set_int(OBJECT(&s->soc), smp_cpus, "enabled-cpus",
199                             &error_abort);
200     int board_rev = version == 3 ? 0xa02082 : 0xa21041;
201     object_property_set_int(OBJECT(&s->soc), board_rev, "board-rev",
202                             &error_abort);
203     object_property_set_bool(OBJECT(&s->soc), true, "realized", &error_abort);
204 
205     /* Create and plug in the SD cards */
206     di = drive_get_next(IF_SD);
207     blk = di ? blk_by_legacy_dinfo(di) : NULL;
208     bus = qdev_get_child_bus(DEVICE(&s->soc), "sd-bus");
209     if (bus == NULL) {
210         error_report("No SD bus found in SOC object");
211         exit(1);
212     }
213     carddev = qdev_create(bus, TYPE_SD_CARD);
214     qdev_prop_set_drive(carddev, "drive", blk, &error_fatal);
215     object_property_set_bool(OBJECT(carddev), true, "realized", &error_fatal);
216 
217     vcram_size = object_property_get_uint(OBJECT(&s->soc), "vcram-size",
218                                           &error_abort);
219     setup_boot(machine, version, machine->ram_size - vcram_size);
220 }
221 
222 static void raspi2_init(MachineState *machine)
223 {
224     raspi_init(machine, 2);
225 }
226 
227 static void raspi2_machine_init(MachineClass *mc)
228 {
229     mc->desc = "Raspberry Pi 2";
230     mc->init = raspi2_init;
231     mc->block_default_type = IF_SD;
232     mc->no_parallel = 1;
233     mc->no_floppy = 1;
234     mc->no_cdrom = 1;
235     mc->max_cpus = BCM283X_NCPUS;
236     mc->min_cpus = BCM283X_NCPUS;
237     mc->default_cpus = BCM283X_NCPUS;
238     mc->default_ram_size = 1024 * 1024 * 1024;
239     mc->ignore_memory_transaction_failures = true;
240 };
241 DEFINE_MACHINE("raspi2", raspi2_machine_init)
242 
243 #ifdef TARGET_AARCH64
244 static void raspi3_init(MachineState *machine)
245 {
246     raspi_init(machine, 3);
247 }
248 
249 static void raspi3_machine_init(MachineClass *mc)
250 {
251     mc->desc = "Raspberry Pi 3";
252     mc->init = raspi3_init;
253     mc->block_default_type = IF_SD;
254     mc->no_parallel = 1;
255     mc->no_floppy = 1;
256     mc->no_cdrom = 1;
257     mc->max_cpus = BCM283X_NCPUS;
258     mc->min_cpus = BCM283X_NCPUS;
259     mc->default_cpus = BCM283X_NCPUS;
260     mc->default_ram_size = 1024 * 1024 * 1024;
261 }
262 DEFINE_MACHINE("raspi3", raspi3_machine_init)
263 #endif
264