From 11facdfb45777e51f62befbf2938768514df24c0 Mon Sep 17 00:00:00 2001 From: SashegDev Date: Mon, 7 Sep 2026 11:40:31 +0000 Subject: [PATCH] saimaa: direct sbl_main start, SMEM, null-page trap; sbl analysis tools; sbl_main=0x802f63e --- qemu/saimaa.c | 320 +++++++++++++++++++++++++++++++++++++++++++++ tools/sbl_adr.py | 52 ++++++++ tools/sbl_mains.py | 36 +++++ tools/sbl_refs.py | 38 ++++++ 4 files changed, 446 insertions(+) create mode 100644 qemu/saimaa.c create mode 100644 tools/sbl_adr.py create mode 100644 tools/sbl_mains.py create mode 100644 tools/sbl_refs.py diff --git a/qemu/saimaa.c b/qemu/saimaa.c new file mode 100644 index 0000000..11f6994 --- /dev/null +++ b/qemu/saimaa.c @@ -0,0 +1,320 @@ +/* + * Nokia Lumia 550 (Saimaa, MSM8909) emulation — WIP. + * Boots real SBL1 (img0.elf from Emergency Payload) on Cortex-A7. + * Most peripherals are trace-stubs; UART prints to stdio. + */ +#include "qemu/osdep.h" +#include "qemu/units.h" +#include "qapi/error.h" +#include "hw/arm/boot.h" +#include "hw/boards.h" +#include "hw/loader.h" +#include "hw/sysbus.h" +#include "hw/sd/sdhci.h" +#include "hw/sd/sd.h" +#include "hw/char/serial.h" +#include "hw/qdev-properties.h" +#include "hw/qdev-properties-system.h" +#include "elf.h" +#include "qom/object.h" +#include "cpu.h" +#include "qemu/error-report.h" +#include "qemu/log.h" + +/* Real MSM8909 map (subset) */ +#define SAIMAA_OCIMEM_BASE 0x00200000 +#define SAIMAA_OCIMEM_SIZE 0x00100000 +#define SAIMAA_DDRLOW_BASE 0x08000000 +#define SAIMAA_DDRLOW_SIZE 0x00600000 +#define SAIMAA_IMEM_BASE 0x08600000 +#define SAIMAA_IMEM_SIZE 0x00010000 +#define SAIMAA_DDRHIGH_BASE 0x80000000 +#define SAIMAA_DDRHIGH_SIZE 0x20000000 +#define SAIMAA_UART_BASE 0x078AF000 +#define SAIMAA_SDHCI_BASE 0x07824900 +#define SAIMAA_GICD_BASE 0x0B000000 +#define SAIMAA_GICC_BASE 0x0B002000 +#define SAIMAA_NCPUS 4 +#define SAIMAA_SMEM_BASE 0x87C00000 +#define SAIMAA_SMEM_SIZE 0x00800000 + +/* ---- minimal MSM UARTDM stub: TX prints, status always ready ---- */ +#define TYPE_SAIMAA_VEC "saimaa-vec" +#define TYPE_SAIMAA_UART "saimaa-uart" +OBJECT_DECLARE_SIMPLE_TYPE(SaimaaUartState, SAIMAA_UART) + +struct SaimaaUartState { + SysBusDevice parent_obj; + MemoryRegion iomem; + /* WIP: plain host stdout, no chardev dance */ +}; + +/* Low vectors / null-page trap: log faulting PC, return 0. */ +static int saimaa_vec_n; +static uint64_t saimaa_vec_read(void *opaque, hwaddr off, unsigned size) +{ + if (saimaa_vec_n < 24) { + ARMCPU *cpu = ARM_CPU(current_cpu); + uint64_t pc = cpu ? cpu->env.regs[15] : 0; + int th = cpu ? cpu->env.thumb : 0; + fprintf(stderr, "saimaa-vec: %s off=0x%x pc=0x%lx\n", + size == 2 ? "fetch?" : "read", + (unsigned)off, (unsigned long)pc - (th ? 4 : 8)); + saimaa_vec_n++; + } + return 0; +} + +static void saimaa_vec_write(void *opaque, hwaddr off, uint64_t val, + unsigned size) +{ +} + +static const MemoryRegionOps saimaa_vec_ops = { + .read = saimaa_vec_read, + .write = saimaa_vec_write, + .endianness = DEVICE_NATIVE_ENDIAN, +}; + +static uint64_t saimaa_uart_read(void *opaque, hwaddr off, unsigned size) +{ + switch (off) { + case 0x08: /* UARTDM_SR: pretend TX ready + empty */ + return 0x000000A0; + case 0x70: /* UARTDM_TF: read returns 0 */ + return 0; + default: + qemu_log_mask(LOG_GUEST_ERROR, + "saimaa-uart: unimp read @0x%x\n", (unsigned)off); + return 0; + } +} + +static void saimaa_uart_write(void *opaque, hwaddr off, uint64_t val, + unsigned size) +{ + SaimaaUartState *s = SAIMAA_UART(opaque); + (void)s; + if (off == 0x70) { /* UARTDM_TF */ + putchar(val & 0xff); + fflush(stdout); + return; + } + qemu_log_mask(LOG_GUEST_ERROR, + "saimaa-uart: unimp write @0x%x = 0x%x\n", + (unsigned)off, (unsigned)val); +} + +static const MemoryRegionOps saimaa_uart_ops = { + .read = saimaa_uart_read, + .write = saimaa_uart_write, + .endianness = DEVICE_NATIVE_ENDIAN, +}; + +static void saimaa_uart_init(Object *obj) +{ + SaimaaUartState *s = SAIMAA_UART(obj); + SysBusDevice *dev = SYS_BUS_DEVICE(obj); + memory_region_init_io(&s->iomem, obj, &saimaa_uart_ops, s, + "saimaa-uart", 0x1000); + sysbus_init_mmio(dev, &s->iomem); +} + +static void saimaa_uart_realize(DeviceState *dev, Error **errp) +{ + /* backend wired directly in machine init; nothing to check */ +} + +/* ---- machine ---- */ +struct SaimaaMachineState { + MachineState parent_obj; + char *sbl1; + char *emmc; + char *sblmain; /* hex: popped-PC override for PBL trampoline */ +}; +typedef struct SaimaaMachineState SaimaaMachineState; + +#define TYPE_SAIMAA_MACHINE MACHINE_TYPE_NAME("saimaa") +OBJECT_DECLARE_SIMPLE_TYPE(SaimaaMachineState, SAIMAA_MACHINE) + +static void saimaa_machine_init(MachineState *machine) +{ + SaimaaMachineState *sms = SAIMAA_MACHINE(machine); + MemoryRegion *sysmem = get_system_memory(); + int i; + + /* RAM map */ + const struct { const char *n; hwaddr b; hwaddr s; } rams[] = { + { "saimaa.ocimem", SAIMAA_OCIMEM_BASE, SAIMAA_OCIMEM_SIZE }, + { "saimaa.ddrlow", SAIMAA_DDRLOW_BASE, SAIMAA_DDRLOW_SIZE }, + { "saimaa.imem", SAIMAA_IMEM_BASE, SAIMAA_IMEM_SIZE }, + { "saimaa.ddrhigh", SAIMAA_DDRHIGH_BASE, SAIMAA_DDRHIGH_SIZE }, + { "saimaa.smem", SAIMAA_SMEM_BASE, SAIMAA_SMEM_SIZE }, + }; + for (i = 0; i < 5; i++) { + MemoryRegion *ram = g_new(MemoryRegion, 1); + memory_region_init_ram(ram, NULL, rams[i].n, rams[i].s, + &error_fatal); + memory_region_add_subregion(sysmem, rams[i].b, ram); + } + + /* CPUs: 4x Cortex-A7, only cpu0 boots */ + for (i = 0; i < SAIMAA_NCPUS; i++) { + Object *cpuobj = object_new("cortex-a7-" TYPE_ARM_CPU); + object_property_set_int(cpuobj, "mp-affinity", i, &error_fatal); + if (i > 0) { + object_property_set_bool(cpuobj, "start-powered-off", true, + &error_fatal); + } + object_property_set_bool(cpuobj, "realized", true, &error_fatal); + } + + /* GICv2 (minimal: dist + cpuif, IRQs wired later) */ + DeviceState *gic = qdev_new("arm_gic"); + qdev_prop_set_uint32(gic, "num-cpu", SAIMAA_NCPUS); + qdev_prop_set_uint32(gic, "num-irq", 160); + sysbus_realize(SYS_BUS_DEVICE(gic), &error_fatal); + sysbus_mmio_map(SYS_BUS_DEVICE(gic), 0, SAIMAA_GICD_BASE); + sysbus_mmio_map(SYS_BUS_DEVICE(gic), 1, SAIMAA_GICC_BASE); + + /* UART at MSM address */ + DeviceState *uart = qdev_new(TYPE_SAIMAA_UART); + sysbus_realize(SYS_BUS_DEVICE(uart), &error_fatal); + sysbus_mmio_map(SYS_BUS_DEVICE(uart), 0, SAIMAA_UART_BASE); + + /* Null-page trap at 0x0 (vectors live here; PBL normally maps ROM) */ + { + MemoryRegion *vec = g_new(MemoryRegion, 1); + memory_region_init_io(vec, NULL, &saimaa_vec_ops, NULL, + "saimaa-vec", 0x1000); + memory_region_add_subregion(sysmem, 0x0, vec); + } + + /* SDHCI + eMMC image */ + DeviceState *sdhci = qdev_new(TYPE_SYSBUS_SDHCI); + sysbus_realize(SYS_BUS_DEVICE(sdhci), &error_fatal); + sysbus_mmio_map(SYS_BUS_DEVICE(sdhci), 0, SAIMAA_SDHCI_BASE); + DriveInfo *di = drive_get(IF_SD, 0, 0); + if (di) { + DeviceState *card = qdev_new(TYPE_SD_CARD); + qdev_prop_set_drive(card, "drive", blk_by_legacy_dinfo(di)); + qdev_realize_and_unref(card, qdev_get_child_bus(sdhci, "sd-bus"), + &error_fatal); + } + + /* Load real SBL1 ELF, jump to entry */ + if (sms->sbl1) { + uint64_t entry = 0; + uint32_t pflags = 0; + ssize_t sz = load_elf(sms->sbl1, NULL, NULL, NULL, &entry, NULL, + NULL, &pflags, 0, EM_ARM, 1, 0); + if (sz < 0) { + error_report("saimaa: cannot load SBL1 %s: %s", sms->sbl1, + load_elf_strerror(sz)); + exit(1); + } + if (sms->sblmain) { + /* + * Direct start at sbl_main: skip the PBL trampoline at + * entry (it BLs into zero padding and pop-zeroes r0-r12). + * Odd address = Thumb code -> set env.thumb (CPSR T). + */ + uint32_t tgt = strtoul(sms->sblmain, NULL, 0); + /* NOTE: pass bit0 through: arm_cpu_set_pc() sets + * regs[15]=tgt&~1 and env.thumb=tgt&1 itself. */ + cpu_set_pc(first_cpu, tgt); + printf("saimaa: direct start -> 0x%x%s (entry 0x%lx skipped)\n", + tgt & ~1u, (tgt & 1) ? " thumb" : " arm", + (unsigned long)entry); + } else { + cpu_set_pc(first_cpu, entry); + } + /* PBL normally sets up SBL stack + r0=pbl_shared; fake it. + * All banked SPs: reset lands in SVC, regs[13] alone is USR. */ + for (int b = 0; b < 8; b++) { + ARM_CPU(first_cpu)->env.banked_r13[b] = 0x085FFF00; + } + ARM_CPU(first_cpu)->env.regs[13] = 0x085FFF00; + ARM_CPU(first_cpu)->env.regs[0] = 0x00220000; /* fake pbl_shared */ + /* sbl_main expects r5 = mem-table pointer (PBL trampoline does + * mov r5, r0 before jumping here); point it at pbl_shared too. */ + ARM_CPU(first_cpu)->env.regs[5] = 0x00220000; + /* (direct-start handled above; no stack override needed) */ + printf("saimaa: SBL1 %s loaded (%zd bytes), entry 0x%lx\n", + sms->sbl1, sz, (unsigned long)entry); + } +} + +static void saimaa_uart_class_init(ObjectClass *oc, void *data) +{ + (void)oc; + (void)data; +} + +static char *saimaa_get_sbl1(Object *obj, Error **errp) +{ + return g_strdup(SAIMAA_MACHINE(obj)->sbl1); +} + +static void saimaa_set_sbl1(Object *obj, const char *value, Error **errp) +{ + SaimaaMachineState *sms = SAIMAA_MACHINE(obj); + g_free(sms->sbl1); + sms->sbl1 = g_strdup(value); +} + +static char *saimaa_get_sblmain(Object *obj, Error **errp) +{ + return g_strdup(SAIMAA_MACHINE(obj)->sblmain); +} + +static void saimaa_set_sblmain(Object *obj, const char *value, Error **errp) +{ + SaimaaMachineState *sms = SAIMAA_MACHINE(obj); + g_free(sms->sblmain); + sms->sblmain = g_strdup(value); +} + +static void saimaa_machine_instance_init(Object *obj) +{ + SaimaaMachineState *sms = SAIMAA_MACHINE(obj); + sms->sbl1 = NULL; + sms->emmc = NULL; + sms->sblmain = NULL; + object_property_add_str(obj, "sbl1", saimaa_get_sbl1, saimaa_set_sbl1); + object_property_add_str(obj, "sblmain", saimaa_get_sblmain, + saimaa_set_sblmain); +} + +static void saimaa_machine_class_init(ObjectClass *oc, void *data) +{ + MachineClass *mc = MACHINE_CLASS(oc); + mc->desc = "Nokia Lumia 550 Saimaa (MSM8909) WIP"; + mc->init = saimaa_machine_init; + mc->max_cpus = SAIMAA_NCPUS; + mc->default_cpus = SAIMAA_NCPUS; + mc->default_ram_size = 512 * MiB; /* only for -m accounting */ +} + +static const TypeInfo saimaa_machine_info = { + .name = TYPE_SAIMAA_MACHINE, + .parent = TYPE_MACHINE, + .instance_size = sizeof(SaimaaMachineState), + .instance_init = saimaa_machine_instance_init, + .class_init = saimaa_machine_class_init, +}; + +static const TypeInfo saimaa_uart_info = { + .name = TYPE_SAIMAA_UART, + .parent = TYPE_SYS_BUS_DEVICE, + .instance_size = sizeof(SaimaaUartState), + .instance_init = saimaa_uart_init, + .class_init = saimaa_uart_class_init, +}; + +static void saimaa_register_types(void) +{ + type_register_static(&saimaa_machine_info); + type_register_static(&saimaa_uart_info); +} +type_init(saimaa_register_types) diff --git a/tools/sbl_adr.py b/tools/sbl_adr.py new file mode 100644 index 0000000..b9fc817 --- /dev/null +++ b/tools/sbl_adr.py @@ -0,0 +1,52 @@ +#!/usr/bin/env python3 +"""sbl_adr.py — поиск ADR (ADD/SUB pc) ссылок на интересные строки SBL1. +Использование: ./tools/sbl_adr.py fw/sbl/img0.elf +""" +import struct +import sys + +d = open(sys.argv[1], "rb").read() +STRINGS = [b"SBL1, Start", b"SBL1, End", b"SBL1, Delta", + b"Sahara: Hello pkt sent", b"bl_power_on", b"sbl1_main"] +svas = {} +for s in STRINGS: + i = d.find(s) + if i < 0: + continue + # find which segment contains it + phoff = struct.unpack("> 7 + imm = ((imm >> rot) | (imm << (32 - rot))) & 0xFFFFFFFF if rot else imm + tgt = (v + j + 8 + (imm if (x & 0x400000) else -imm)) & 0xFFFFFFFF + if abs(tgt - va) < 0x100: + print(" ", hex(v + j), "->", hex(tgt)) + n += 1 + if n > 6: + break diff --git a/tools/sbl_mains.py b/tools/sbl_mains.py new file mode 100644 index 0000000..52d4644 --- /dev/null +++ b/tools/sbl_mains.py @@ -0,0 +1,36 @@ +#!/usr/bin/env python3 +"""sbl_mains.py — кандидаты в sbl_main: плотность BL + близость строк boot-лога. +Использование: ./tools/sbl_mains.py fw/sbl/img0.elf +""" +import struct +import sys + +d = open(sys.argv[1], "rb").read() +phoff = struct.unpack("> 25) == 0b101 and (y & 0x01000000): + bls += 1 + if bls >= 8: + cands.append((bls, v + j)) +cands.sort(reverse=True) +print("top candidates (bl-count, addr):") +for bls, a in cands[:15]: + print(f" {bls:3d} {a:#x}") diff --git a/tools/sbl_refs.py b/tools/sbl_refs.py new file mode 100644 index 0000000..3d215e8 --- /dev/null +++ b/tools/sbl_refs.py @@ -0,0 +1,38 @@ +#!/usr/bin/env python3 +"""sbl_refs.py — поиск кодовых ссылок на строку в SBL1 (img0.elf, seg 0x8005800). +Использование: ./tools/sbl_refs.py fw/sbl/img0.elf 'SBL1, Start' +""" +import struct +import sys + +path, needle = sys.argv[1], sys.argv[2].encode() +d = open(path, "rb").read() +i = d.find(needle) +print("str fileoff:", hex(i)) +SEG_OFF, SEG_VA, SEG_SZ = 0x3000, 0x8005800, 0x33A54 +va = SEG_VA + (i - SEG_OFF) +print("str VA:", hex(va)) +# search ALL segments for pc-relative loads to it +import re + +def segs(d): + phoff = struct.unpack("> 12) & 15), "->", hex(tgt))