[RFC PATCH v4 25/30] hw/loongarch: Add default bios startup support.

[Xiaojuan Yang <yangxiaojuan@loongson.cn>]

Signed-off-by: Xiaojuan Yang <yangxiaojuan@loongson.cn>
Signed-off-by: Song Gao <gaosong@loongson.cn>
---
 hw/loongarch/Kconfig             |  4 ++++
 hw/loongarch/fw_cfg.c            | 33 ++++++++++++++++++++++++++++++
 hw/loongarch/fw_cfg.h            | 15 ++++++++++++++
 hw/loongarch/loongson3.c         | 35 ++++++++++++++++++++++++++++++++
 hw/loongarch/meson.build         |  1 +
 include/hw/loongarch/loongarch.h |  8 ++++++++
 6 files changed, 96 insertions(+)
 create mode 100644 hw/loongarch/fw_cfg.c
 create mode 100644 hw/loongarch/fw_cfg.h

diff --git a/hw/loongarch/Kconfig b/hw/loongarch/Kconfig
index 0f759eaa37..06bfb82b1d 100644
--- a/hw/loongarch/Kconfig
+++ b/hw/loongarch/Kconfig
@@ -13,3 +13,7 @@ config LOONGSON3_LS7A
     select LOONGARCH_PCH_MSI
     select LOONGARCH_EXTIOI
     select LS7A_RTC
+    select FW_CFG_LOONGARCH
+
+config FW_CFG_LOONGARCH
+    bool
diff --git a/hw/loongarch/fw_cfg.c b/hw/loongarch/fw_cfg.c
new file mode 100644
index 0000000000..4cefffc896
--- /dev/null
+++ b/hw/loongarch/fw_cfg.c
@@ -0,0 +1,33 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * QEMU fw_cfg helpers (LoongArch specific)
+ *
+ * Copyright (C) 2021 Loongson Technology Corporation Limited
+ */
+
+#include "qemu/osdep.h"
+#include "hw/loongarch/fw_cfg.h"
+#include "hw/loongarch/loongarch.h"
+#include "hw/nvram/fw_cfg.h"
+#include "sysemu/sysemu.h"
+
+static void fw_cfg_boot_set(void *opaque, const char *boot_device,
+                            Error **errp)
+{
+    fw_cfg_modify_i16(opaque, FW_CFG_BOOT_DEVICE, boot_device[0]);
+}
+
+FWCfgState *loongarch_fw_cfg_init(ram_addr_t ram_size, MachineState *ms)
+{
+    FWCfgState *fw_cfg;
+    int max_cpus = ms->smp.max_cpus;
+    int smp_cpus = ms->smp.cpus;
+
+    fw_cfg = fw_cfg_init_mem_wide(FW_CFG_ADDR + 8, FW_CFG_ADDR, 8, 0, NULL);
+    fw_cfg_add_i16(fw_cfg, FW_CFG_MAX_CPUS, (uint16_t)max_cpus);
+    fw_cfg_add_i64(fw_cfg, FW_CFG_RAM_SIZE, (uint64_t)ram_size);
+    fw_cfg_add_i16(fw_cfg, FW_CFG_NB_CPUS, (uint16_t)smp_cpus);
+
+    qemu_register_boot_set(fw_cfg_boot_set, fw_cfg);
+    return fw_cfg;
+}
diff --git a/hw/loongarch/fw_cfg.h b/hw/loongarch/fw_cfg.h
new file mode 100644
index 0000000000..7c0de4db4a
--- /dev/null
+++ b/hw/loongarch/fw_cfg.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * QEMU fw_cfg helpers (LoongArch specific)
+ *
+ * Copyright (C) 2021 Loongson Technology Corporation Limited
+ */
+
+#ifndef HW_LOONGARCH_FW_CFG_H
+#define HW_LOONGARCH_FW_CFG_H
+
+#include "hw/boards.h"
+#include "hw/nvram/fw_cfg.h"
+
+FWCfgState *loongarch_fw_cfg_init(ram_addr_t ram_size, MachineState *ms);
+#endif
diff --git a/hw/loongarch/loongson3.c b/hw/loongarch/loongson3.c
index ff0ef71e7b..31c285a74d 100644
--- a/hw/loongarch/loongson3.c
+++ b/hw/loongarch/loongson3.c
@@ -17,6 +17,8 @@
 #include "sysemu/reset.h"
 #include "hw/irq.h"
 #include "net/net.h"
+#include "hw/loader.h"
+#include "elf.h"
 #include "hw/loongarch/loongarch.h"
 #include "hw/intc/loongarch_ipi.h"
 #include "hw/intc/loongarch_extioi.h"
@@ -24,6 +26,9 @@
 #include "hw/intc/loongarch_pch_msi.h"
 #include "hw/pci-host/ls7a.h"
 #include "hw/misc/unimp.h"
+#include "hw/loongarch/fw_cfg.h"
+
+#define LOONGSON3_BIOSNAME "loongarch_bios.bin"
 
 static void loongarch_cpu_reset(void *opaque)
 {
@@ -260,6 +265,8 @@ static void loongarch_init(MachineState *machine)
     MemoryRegion *address_space_mem = get_system_memory();
     LoongArchMachineState *lams = LOONGARCH_MACHINE(machine);
     int i;
+    int bios_size;
+    char *filename;
 
     if (!cpu_model) {
         cpu_model = LOONGARCH_CPU_TYPE_NAME("Loongson-3A5000");
@@ -284,6 +291,11 @@ static void loongarch_init(MachineState *machine)
         LOONGARCH_SIMPLE_MMIO_OPS(MISC_FUNC_REG, "loongarch_misc_func", 0x8, 3);
     }
 
+    if (ram_size < 1 * GiB) {
+        error_report("ram_size must be greater than 1G due to the bios memory layout");
+        exit(1);
+    }
+
     /* Add memory region */
     memory_region_init_alias(&lams->lowmem, NULL, "loongarch.lowram",
                              machine->ram, 0, 256 * MiB);
@@ -302,6 +314,28 @@ static void loongarch_init(MachineState *machine)
     memory_region_add_subregion(get_system_memory(), LOONGARCH_ISA_IO_BASE,
                                 &lams->isa_io);
 
+    /* load the BIOS image. */
+    filename = qemu_find_file(QEMU_FILE_TYPE_BIOS,
+                              machine->firmware ?: LOONGSON3_BIOSNAME);
+    if (filename) {
+        bios_size = load_image_targphys(filename, LA_BIOS_BASE, LA_BIOS_SIZE);
+        lams->fw_cfg = loongarch_fw_cfg_init(ram_size, machine);
+        rom_set_fw(lams->fw_cfg);
+        g_free(filename);
+    } else {
+        bios_size = -1;
+    }
+
+    if ((bios_size < 0 || bios_size > LA_BIOS_SIZE) && !qtest_enabled()) {
+        error_report("Could not load LOONGARCH bios '%s'", machine->firmware);
+        exit(1);
+    }
+
+    memory_region_init_ram(&lams->bios, NULL, "loongarch.bios",
+                           LA_BIOS_SIZE, &error_fatal);
+    memory_region_set_readonly(&lams->bios, true);
+    memory_region_add_subregion(get_system_memory(), LA_BIOS_BASE, &lams->bios);
+
     /* Initialize the IO interrupt subsystem */
     loongarch_irq_init(lams);
 }
@@ -317,6 +351,7 @@ static void loongarch_class_init(ObjectClass *oc, void *data)
     mc->default_ram_id = "loongarch.ram";
     mc->max_cpus = LOONGARCH_MAX_VCPUS;
     mc->is_default = 1;
+    mc->default_machine_opts = "firmware=loongarch_bios.bin";
     mc->default_kernel_irqchip_split = false;
     mc->block_default_type = IF_VIRTIO;
     mc->default_boot_order = "c";
diff --git a/hw/loongarch/meson.build b/hw/loongarch/meson.build
index 1db3529cbc..fed69dfb62 100644
--- a/hw/loongarch/meson.build
+++ b/hw/loongarch/meson.build
@@ -1,4 +1,5 @@
 loongarch_ss = ss.source_set()
 loongarch_ss.add(when: 'CONFIG_LOONGSON3_LS7A', if_true: files('loongson3.c'))
+loongarch_ss.add(when: 'CONFIG_FW_CFG_LOONGARCH', if_true: files('fw_cfg.c'))
 
 hw_arch += {'loongarch': loongarch_ss}
diff --git a/include/hw/loongarch/loongarch.h b/include/hw/loongarch/loongarch.h
index fd95fbce91..59bbea86fe 100644
--- a/include/hw/loongarch/loongarch.h
+++ b/include/hw/loongarch/loongarch.h
@@ -35,6 +35,10 @@
 #define LOONGARCH_ISA_IO_BASE   0x18000000UL
 #define LOONGARCH_ISA_IO_SIZE   0x0004000
 
+#define FW_CFG_ADDR             0x1e020000
+#define LA_BIOS_BASE            0x1c000000
+#define LA_BIOS_SIZE            (4 * 1024 * 1024)
+
 typedef struct LoongArchMachineState {
     /*< private >*/
     MachineState parent_obj;
@@ -42,6 +46,10 @@ typedef struct LoongArchMachineState {
     MemoryRegion lowmem;
     MemoryRegion highmem;
     MemoryRegion isa_io;
+    MemoryRegion bios;
+
+    /* State for other subsystems/APIs: */
+    FWCfgState  *fw_cfg;
 } LoongArchMachineState;
 
 #define TYPE_LOONGARCH_MACHINE  MACHINE_TYPE_NAME("loongson3-ls7a")
-- 
2.27.0