hw/arm/raspi.c

   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 /* Based on versatilepb.c, copyright terms below. */
  12
  13 /*
  14  * ARM Versatile Platform/Application Baseboard System emulation.
  15  *
  16  * Copyright (c) 2005-2007 CodeSourcery.
  17  * Written by Paul Brook
  18  *
  19  * This code is licensed under the GPL.
  20  */
  21
  22 #include "hw/arm/bcm2836.h"
  23 #include "qemu/error-report.h"
  24 #include "hw/boards.h"
  25 #include "hw/loader.h"
  26 #include "hw/arm/arm.h"
  27 #include "sysemu/sysemu.h"
  28
  29 #define SMPBOOT_ADDR    0x300 /* this should leave enough space for ATAGS */
  30 #define MVBAR_ADDR      0x400 /* secure vectors */
  31 #define BOARDSETUP_ADDR (MVBAR_ADDR + 0x20) /* board setup code */
  32 #define FIRMWARE_ADDR   0x8000 /* Pi loads kernel.img here by default */
  33
  34 /* Table of Linux board IDs for different Pi versions */
  35 static const int raspi_boardid[] = {[1] = 0xc42, [2] = 0xc43};
  36
  37 typedef struct RaspiMachineState {
  38     union {
  39         Object obj;
  40         BCM2836State pi2;
  41     } soc;
  42     MemoryRegion ram;
  43 } RaspiMachineState;
  44
  45 static void write_smpboot(ARMCPU *cpu, const struct arm_boot_info *info)
  46 {
  47     static const uint32_t smpboot[] = {
  48         0xE1A0E00F, /*    mov     lr, pc */
  49         0xE3A0FE42, /*    mov     pc, #0x420           ;call BOARDSETUP_ADDR */
  50         0xEE100FB0, /*    mrc     p15, 0, r0, c0, c0, 5;get core ID */
  51         0xE7E10050, /*    ubfx    r0, r0, #0, #2       ;extract LSB */
  52         0xE59F5014, /*    ldr     r5, =0x400000CC      ;load mbox base */
  53         0xE320F001, /* 1: yield */
  54         0xE7953200, /*    ldr     r3, [r5, r0, lsl #4] ;read mbox for our core*/
  55         0xE3530000, /*    cmp     r3, #0               ;spin while zero */
  56         0x0AFFFFFB, /*    beq     1b */
  57         0xE7853200, /*    str     r3, [r5, r0, lsl #4] ;clear mbox */
  58         0xE12FFF13, /*    bx      r3                   ;jump to target */
  59         0x400000CC, /* (constant: mailbox 3 read/clear base) */
  60     };
  61
  62     assert(SMPBOOT_ADDR + sizeof(smpboot) <= MVBAR_ADDR);
  63     rom_add_blob_fixed("raspi_smpboot", smpboot, sizeof(smpboot),
  64                        info->smp_loader_start);
  65 }
  66
  67 static void write_board_setup(ARMCPU *cpu, const struct arm_boot_info *info)
  68 {
  69     static const uint32_t board_setup[] = {
  70         /* MVBAR_ADDR: secure monitor vectors */
  71         0xEAFFFFFE, /* (spin) */
  72         0xEAFFFFFE, /* (spin) */
  73         0xE1B0F00E, /* movs pc, lr ;SMC exception return */
  74         0xEAFFFFFE, /* (spin) */
  75         0xEAFFFFFE, /* (spin) */
  76         0xEAFFFFFE, /* (spin) */
  77         0xEAFFFFFE, /* (spin) */
  78         0xEAFFFFFE, /* (spin) */
  79         /* BOARDSETUP_ADDR */
  80         0xE3A00B01, /* mov     r0, #0x400             ;MVBAR_ADDR */
  81         0xEE0C0F30, /* mcr     p15, 0, r0, c12, c0, 1 ;set MVBAR */
  82         0xE3A00031, /* mov     r0, #0x31              ;enable AW, FW, NS */
  83         0xEE010F11, /* mcr     p15, 0, r0, c1, c1, 0  ;write SCR */
  84         0xE1A0100E, /* mov     r1, lr                 ;save LR across SMC */
  85         0xE1600070, /* smc     #0                     ;monitor call */
  86         0xE1A0F001, /* mov     pc, r1                 ;return */
  87     };
  88
  89     rom_add_blob_fixed("raspi_boardsetup", board_setup, sizeof(board_setup),
  90                        MVBAR_ADDR);
  91 }
  92
  93 static void reset_secondary(ARMCPU *cpu, const struct arm_boot_info *info)
  94 {
  95     CPUState *cs = CPU(cpu);
  96     cpu_set_pc(cs, info->smp_loader_start);
  97 }
  98
  99 static void setup_boot(MachineState *machine, int version, size_t ram_size)
 100 {
 101     static struct arm_boot_info binfo;
 102     int r;
 103
 104     binfo.board_id = raspi_boardid[version];
 105     binfo.ram_size = ram_size;
 106     binfo.nb_cpus = smp_cpus;
 107     binfo.board_setup_addr = BOARDSETUP_ADDR;
 108     binfo.write_board_setup = write_board_setup;
 109     binfo.secure_board_setup = true;
 110     binfo.secure_boot = true;
 111
 112     /* Pi2 requires SMP setup */
 113     if (version == 2) {
 114         binfo.smp_loader_start = SMPBOOT_ADDR;
 115         binfo.write_secondary_boot = write_smpboot;
 116         binfo.secondary_cpu_reset_hook = reset_secondary;
 117     }
 118
 119     /* If the user specified a "firmware" image (e.g. UEFI), we bypass
 120        the normal Linux boot process */
 121     if (machine->firmware) {
 122         /* load the firmware image (typically kernel.img) */
 123         r = load_image_targphys(machine->firmware, FIRMWARE_ADDR,
 124                                 ram_size - FIRMWARE_ADDR);
 125         if (r < 0) {
 126             error_report("Failed to load firmware from %s", machine->firmware);
 127             exit(1);
 128         }
 129
 130         /* set variables so arm_load_kernel does the right thing */
 131         binfo.entry = FIRMWARE_ADDR;
 132         binfo.firmware_loaded = true;
 133     } else {
 134         /* Just let arm_load_kernel do everything for us... */
 135         binfo.kernel_filename = machine->kernel_filename;
 136         binfo.kernel_cmdline = machine->kernel_cmdline;
 137         binfo.initrd_filename = machine->initrd_filename;
 138     }
 139
 140     arm_load_kernel(ARM_CPU(first_cpu), &binfo);
 141 }
 142
 143 static void raspi2_init(MachineState *machine)
 144 {
 145     RaspiMachineState *s = g_new0(RaspiMachineState, 1);
 146
 147     /* Initialise the SOC */
 148     object_initialize(&s->soc.pi2, sizeof(s->soc.pi2), TYPE_BCM2836);
 149     object_property_add_child(OBJECT(machine), "soc", &s->soc.obj,
 150                               &error_abort);
 151
 152     /* Allocate and map RAM */
 153     memory_region_allocate_system_memory(&s->ram, OBJECT(machine), "ram",
 154                                          machine->ram_size);
 155     memory_region_add_subregion_overlap(get_system_memory(), 0, &s->ram, 0);
 156
 157     /* Setup the SOC */
 158     object_property_add_const_link(&s->soc.obj, "ram", OBJECT(&s->ram),
 159                                    &error_abort);
 160     object_property_set_bool(&s->soc.obj, true, "realized", &error_abort);
 161
 162     /* Boot! */
 163     setup_boot(machine, 2, machine->ram_size);
 164 }
 165
 166 static void raspi2_machine_init(MachineClass *mc)
 167 {
 168     mc->desc = "Raspberry Pi 2";
 169     mc->init = raspi2_init;
 170     mc->block_default_type = IF_SD;
 171     mc->no_parallel = 1;
 172     mc->no_floppy = 1;
 173     mc->no_cdrom = 1;
 174     mc->max_cpus = BCM2836_NCPUS;
 175     /* XXX: Temporary restriction in RAM size from the full 1GB. Since
 176      * we do not yet support the framebuffer / GPU, we need to limit
 177      * RAM usable by the OS to sit below the peripherals. */
 178     mc->default_ram_size = 0x3F000000; /* BCM2836_PERI_BASE */
 179 };
 180 DEFINE_MACHINE("raspi2", raspi2_machine_init)