xref: /openbmc/qemu/hw/arm/raspi.c (revision c964b660)
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  * This code is licensed under the GNU GPLv2 and later.
9  */
10 
11 #include "qemu/osdep.h"
12 #include "hw/arm/bcm2836.h"
13 #include "qemu/error-report.h"
14 #include "hw/boards.h"
15 #include "hw/loader.h"
16 #include "hw/arm/arm.h"
17 #include "sysemu/sysemu.h"
18 
19 #define SMPBOOT_ADDR    0x300 /* this should leave enough space for ATAGS */
20 #define MVBAR_ADDR      0x400 /* secure vectors */
21 #define BOARDSETUP_ADDR (MVBAR_ADDR + 0x20) /* board setup code */
22 #define FIRMWARE_ADDR   0x8000 /* Pi loads kernel.img here by default */
23 
24 /* Table of Linux board IDs for different Pi versions */
25 static const int raspi_boardid[] = {[1] = 0xc42, [2] = 0xc43};
26 
27 typedef struct RasPiState {
28     BCM2836State soc;
29     MemoryRegion ram;
30 } RasPiState;
31 
32 static void write_smpboot(ARMCPU *cpu, const struct arm_boot_info *info)
33 {
34     static const uint32_t smpboot[] = {
35         0xe1a0e00f, /*    mov     lr, pc */
36         0xe3a0fe00 + (BOARDSETUP_ADDR >> 4), /* mov pc, BOARDSETUP_ADDR */
37         0xee100fb0, /*    mrc     p15, 0, r0, c0, c0, 5;get core ID */
38         0xe7e10050, /*    ubfx    r0, r0, #0, #2       ;extract LSB */
39         0xe59f5014, /*    ldr     r5, =0x400000CC      ;load mbox base */
40         0xe320f001, /* 1: yield */
41         0xe7953200, /*    ldr     r3, [r5, r0, lsl #4] ;read mbox for our core*/
42         0xe3530000, /*    cmp     r3, #0               ;spin while zero */
43         0x0afffffb, /*    beq     1b */
44         0xe7853200, /*    str     r3, [r5, r0, lsl #4] ;clear mbox */
45         0xe12fff13, /*    bx      r3                   ;jump to target */
46         0x400000cc, /* (constant: mailbox 3 read/clear base) */
47     };
48 
49     /* check that we don't overrun board setup vectors */
50     QEMU_BUILD_BUG_ON(SMPBOOT_ADDR + sizeof(smpboot) > MVBAR_ADDR);
51     /* check that board setup address is correctly relocated */
52     QEMU_BUILD_BUG_ON((BOARDSETUP_ADDR & 0xf) != 0
53                       || (BOARDSETUP_ADDR >> 4) >= 0x100);
54 
55     rom_add_blob_fixed("raspi_smpboot", smpboot, sizeof(smpboot),
56                        info->smp_loader_start);
57 }
58 
59 static void write_board_setup(ARMCPU *cpu, const struct arm_boot_info *info)
60 {
61     arm_write_secure_board_setup_dummy_smc(cpu, info, MVBAR_ADDR);
62 }
63 
64 static void reset_secondary(ARMCPU *cpu, const struct arm_boot_info *info)
65 {
66     CPUState *cs = CPU(cpu);
67     cpu_set_pc(cs, info->smp_loader_start);
68 }
69 
70 static void setup_boot(MachineState *machine, int version, size_t ram_size)
71 {
72     static struct arm_boot_info binfo;
73     int r;
74 
75     binfo.board_id = raspi_boardid[version];
76     binfo.ram_size = ram_size;
77     binfo.nb_cpus = smp_cpus;
78     binfo.board_setup_addr = BOARDSETUP_ADDR;
79     binfo.write_board_setup = write_board_setup;
80     binfo.secure_board_setup = true;
81     binfo.secure_boot = true;
82 
83     /* Pi2 requires SMP setup */
84     if (version == 2) {
85         binfo.smp_loader_start = SMPBOOT_ADDR;
86         binfo.write_secondary_boot = write_smpboot;
87         binfo.secondary_cpu_reset_hook = reset_secondary;
88     }
89 
90     /* If the user specified a "firmware" image (e.g. UEFI), we bypass
91      * the normal Linux boot process
92      */
93     if (machine->firmware) {
94         /* load the firmware image (typically kernel.img) */
95         r = load_image_targphys(machine->firmware, FIRMWARE_ADDR,
96                                 ram_size - FIRMWARE_ADDR);
97         if (r < 0) {
98             error_report("Failed to load firmware from %s", machine->firmware);
99             exit(1);
100         }
101 
102         binfo.entry = FIRMWARE_ADDR;
103         binfo.firmware_loaded = true;
104     } else {
105         binfo.kernel_filename = machine->kernel_filename;
106         binfo.kernel_cmdline = machine->kernel_cmdline;
107         binfo.initrd_filename = machine->initrd_filename;
108     }
109 
110     arm_load_kernel(ARM_CPU(first_cpu), &binfo);
111 }
112 
113 static void raspi2_init(MachineState *machine)
114 {
115     RasPiState *s = g_new0(RasPiState, 1);
116 
117     object_initialize(&s->soc, sizeof(s->soc), TYPE_BCM2836);
118     object_property_add_child(OBJECT(machine), "soc", OBJECT(&s->soc),
119                               &error_abort);
120 
121     /* Allocate and map RAM */
122     memory_region_allocate_system_memory(&s->ram, OBJECT(machine), "ram",
123                                          machine->ram_size);
124     /* FIXME: Remove when we have custom CPU address space support */
125     memory_region_add_subregion_overlap(get_system_memory(), 0, &s->ram, 0);
126 
127     /* Setup the SOC */
128     object_property_add_const_link(OBJECT(&s->soc), "ram", OBJECT(&s->ram),
129                                    &error_abort);
130     object_property_set_int(OBJECT(&s->soc), smp_cpus, "enabled-cpus",
131                             &error_abort);
132     object_property_set_int(OBJECT(&s->soc), 0xa21041, "board-rev",
133                             &error_abort);
134     object_property_set_bool(OBJECT(&s->soc), true, "realized", &error_abort);
135 
136     setup_boot(machine, 2, machine->ram_size);
137 }
138 
139 static void raspi2_machine_init(MachineClass *mc)
140 {
141     mc->desc = "Raspberry Pi 2";
142     mc->init = raspi2_init;
143     mc->block_default_type = IF_SD;
144     mc->no_parallel = 1;
145     mc->no_floppy = 1;
146     mc->no_cdrom = 1;
147     mc->max_cpus = BCM2836_NCPUS;
148 
149     /* XXX: Temporary restriction in RAM size from the full 1GB. Since
150      * we do not yet support the framebuffer / GPU, we need to limit
151      * RAM usable by the OS to sit below the peripherals.
152      */
153     mc->default_ram_size = 0x3F000000; /* BCM2836_PERI_BASE */
154 };
155 DEFINE_MACHINE("raspi2", raspi2_machine_init)
156