Am 24.11.2011 00:59, schrieb Andreas Färber: > Unlike PowerPC, an architecture that I'm trying to emulate does not > store branch instructions in the reset vector but a memory address. I'm > therefore trying to read physical address 0x00000 and store its value > into my env->pc. > > I've verified by running with -S that xp /xh 0x00000 shows the expected > value. > > When doing lduw_phys(0x00000) or cpu_read_physical_memory() in the CPU > reset function though, I just seem to read from uninitialized memory > (0xbaba). I've taken care to reorder CPU initialization to after the > BIOS file is loaded in the machine initialization function.
Another weird memory issue is that tcg_gen_qemu_st16() succeeds but the value stored doesn't show up with xp or x on the monitor but 0x0000. MOVW 0xf8,#0xfee0 (at 0x02010) is trying to write 0xfee0 to 0xFFFf8. Similarly, a subsequent tcg_gen_qemu_ld16u() reads 0x0000 from there. TCG snippet: https://github.com/afaerber/qemu-rl78/commit/d3880bd53a26d224c56d16a6ea5950019d411cf0 uint8_t sfrp = ldub_code(s->pc + 1) & ~0x1; uint16_t data = lduw_code(s->pc + 2); LOG_DISAS("MOVW 0x%" PRIx8 ",#0x%04" PRIx16 "\n", sfrp, data); TCGv addr = tcg_const_tl(0xFFF00 | sfrp); TCGv_i32 val = tcg_const_i32(data); tcg_gen_qemu_st16(val, addr, 0); /* for testing: */ tcg_gen_qemu_ld16u(env_sp, addr, 0); tcg_temp_free(addr); tcg_temp_free(val); (qemu) info mtree memory 00000000-fffffffe (prio 0): system 00000000-0000ffff (prio 0): rl78g13_pb.code_flash 000fef00-000ffeff (prio 0): rl78g13_pb.ram 000ffee0-000ffeff (prio 0): rl78g13_pb.gpr 000fff00-000fffff (prio 0): rl78g13_pb.sfr https://github.com/afaerber/qemu-rl78/blob/d3880bd53a26d224c56d16a6ea5950019d411cf0/hw/rl78g13_pb.c#L88 memory_region_init_ram(sfr, NULL, "rl78g13_pb.sfr", 256); memory_region_add_subregion(get_system_memory(), 0xFFF00, sfr); Anything obvious that I'm missing? Thanks, Andreas
