LXR qemu/hw/nios2/generic

   1/*
   2 * Generic simulator target with no MMU or devices.  This emulation is
   3 * compatible with the libgloss qemu-hosted.ld linker script for using
   4 * QEMU as an instruction set simulator.
   5 *
   6 * Copyright (c) 2018-2019 Mentor Graphics
   7 *
   8 * Copyright (c) 2016 Marek Vasut <marek.vasut@gmail.com>
   9 *
  10 * Based on LabX device code
  11 *
  12 * Copyright (c) 2012 Chris Wulff <crwulff@gmail.com>
  13 *
  14 * This library is free software; you can redistribute it and/or
  15 * modify it under the terms of the GNU Lesser General Public
  16 * License as published by the Free Software Foundation; either
  17 * version 2.1 of the License, or (at your option) any later version.
  18 *
  19 * This library is distributed in the hope that it will be useful,
  20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  22 * Lesser General Public License for more details.
  23 *
  24 * You should have received a copy of the GNU Lesser General Public
  25 * License along with this library; if not, see
  26 * <http://www.gnu.org/licenses/lgpl-2.1.html>
  27 */
  28
  29#include "qemu/osdep.h"
  30#include "qapi/error.h"
  31#include "qemu-common.h"
  32#include "cpu.h"
  33
  34#include "hw/sysbus.h"
  35#include "hw/hw.h"
  36#include "hw/char/serial.h"
  37#include "sysemu/sysemu.h"
  38#include "hw/boards.h"
  39#include "exec/memory.h"
  40#include "exec/address-spaces.h"
  41#include "qemu/config-file.h"
  42
  43#include "boot.h"
  44
  45#define BINARY_DEVICE_TREE_FILE    "generic-nommu.dtb"
  46
  47static void nios2_generic_nommu_init(MachineState *machine)
  48{
  49    Nios2CPU *cpu;
  50    MemoryRegion *address_space_mem = get_system_memory();
  51    MemoryRegion *phys_tcm = g_new(MemoryRegion, 1);
  52    MemoryRegion *phys_tcm_alias = g_new(MemoryRegion, 1);
  53    MemoryRegion *phys_ram = g_new(MemoryRegion, 1);
  54    MemoryRegion *phys_ram_alias = g_new(MemoryRegion, 1);
  55    ram_addr_t tcm_base = 0x0;
  56    ram_addr_t tcm_size = 0x1000;    /* 1 kiB, but QEMU limit is 4 kiB */
  57    ram_addr_t ram_base = 0x10000000;
  58    ram_addr_t ram_size = 0x08000000;
  59
  60    /* Physical TCM (tb_ram_1k) with alias at 0xc0000000 */
  61    memory_region_init_ram(phys_tcm, NULL, "nios2.tcm", tcm_size,
  62                           &error_abort);
  63    memory_region_init_alias(phys_tcm_alias, NULL, "nios2.tcm.alias",
  64                             phys_tcm, 0, tcm_size);
  65    memory_region_add_subregion(address_space_mem, tcm_base, phys_tcm);
  66    memory_region_add_subregion(address_space_mem, 0xc0000000 + tcm_base,
  67                                phys_tcm_alias);
  68
  69    /* Physical DRAM with alias at 0xc0000000 */
  70    memory_region_init_ram(phys_ram, NULL, "nios2.ram", ram_size,
  71                           &error_abort);
  72    memory_region_init_alias(phys_ram_alias, NULL, "nios2.ram.alias",
  73                             phys_ram, 0, ram_size);
  74    memory_region_add_subregion(address_space_mem, ram_base, phys_ram);
  75    memory_region_add_subregion(address_space_mem, 0xc0000000 + ram_base,
  76                                phys_ram_alias);
  77
  78    cpu = NIOS2_CPU(cpu_create(TYPE_NIOS2_CPU));
  79
  80    /* Remove MMU */
  81    cpu->mmu_present = false;
  82
  83    /* Reset vector is the first 32 bytes of RAM.  */
  84    cpu->reset_addr = ram_base;
  85
  86    /* The interrupt vector comes right after reset.  */
  87    cpu->exception_addr = ram_base + 0x20;
  88
  89    /*
  90     * The linker script does have a TLB miss memory region declared,
  91     * but this should never be used with no MMU.
  92     */
  93    cpu->fast_tlb_miss_addr = 0x7fff400;
  94
  95    nios2_load_kernel(cpu, ram_base, ram_size, machine->initrd_filename,
  96                      BINARY_DEVICE_TREE_FILE, NULL);
  97}
  98
  99static void nios2_generic_nommu_machine_init(struct MachineClass *mc)
 100{
 101    mc->desc = "Generic NOMMU Nios II design";
 102    mc->init = nios2_generic_nommu_init;
 103}
 104
 105DEFINE_MACHINE("nios2-generic-nommu", nios2_generic_nommu_machine_init);
 106