[RFC PATCH v7 28/29] hw/loongarch: Add fdt support.

[Xiaojuan Yang]

Add tree nodes for 3A5000 device tree.
- cpu nodes;
- fw_cfg nodes;
- pcie nodes.

The lastest loongarch bios have supported fdt.
- https://github.com/loongson/edk2
- https://github.com/loongson/edk2-platforms

Signed-off-by: Xiaojuan Yang <yangxiaojuan@loongson.cn>
Signed-off-by: Song Gao <gaosong@loongson.cn>
---
 hw/loongarch/loongson3.c         | 136 +++++++++++++++++++++++++++++++
 include/hw/loongarch/loongarch.h |   4 +
 target/loongarch/cpu.c           |   2 +
 target/loongarch/cpu.h           |   3 +
 4 files changed, 145 insertions(+)

diff --git a/hw/loongarch/loongson3.c b/hw/loongarch/loongson3.c
index 5f0dcfa419..0ae6075a3e 100644
--- a/hw/loongarch/loongson3.c
+++ b/hw/loongarch/loongson3.c
@@ -34,6 +34,9 @@
 #include "hw/firmware/smbios.h"
 #include "hw/acpi/aml-build.h"
 #include "qapi/qapi-visit-common.h"
+#include "sysemu/device_tree.h"
+
+#include <libfdt.h>
 
 #include "target/loongarch/cpu.h"
 
@@ -447,6 +450,126 @@ static void loongarch_irq_init(LoongArchMachineState 
*lams,
     loongarch_devices_init(pch_pic);
 }
 
+static void create_fdt(LoongArchMachineState *lams)
+{
+    MachineState *ms = MACHINE(lams);
+
+    ms->fdt = create_device_tree(&lams->fdt_size);
+    if (!ms->fdt) {
+        error_report("create_device_tree() failed");
+        exit(1);
+    }
+
+    /* Header */
+    qemu_fdt_setprop_string(ms->fdt, "/", "compatible",
+                            "linux,dummy-loongson3");
+    qemu_fdt_setprop_cell(ms->fdt, "/", "#address-cells", 0x2);
+    qemu_fdt_setprop_cell(ms->fdt, "/", "#size-cells", 0x2);
+}
+
+static void fdt_add_cpu_nodes(const LoongArchMachineState *lams)
+{
+    int num;
+    const MachineState *ms = MACHINE(lams);
+    int smp_cpus = ms->smp.cpus;
+
+    qemu_fdt_add_subnode(ms->fdt, "/cpus");
+    qemu_fdt_setprop_cell(ms->fdt, "/cpus", "#address-cells", 0x1);
+    qemu_fdt_setprop_cell(ms->fdt, "/cpus", "#size-cells", 0x0);
+
+    /* cpu nodes */
+    for (num = smp_cpus - 1; num >= 0; num--) {
+        char *nodename = g_strdup_printf("/cpus/cpu@%d", num);
+        LoongArchCPU *cpu = LOONGARCH_CPU(qemu_get_cpu(num));
+
+        qemu_fdt_add_subnode(ms->fdt, nodename);
+        qemu_fdt_setprop_string(ms->fdt, nodename, "device_type", "cpu");
+        qemu_fdt_setprop_string(ms->fdt, nodename, "compatible",
+                                cpu->dtb_compatible);
+        qemu_fdt_setprop_cell(ms->fdt, nodename, "reg", num);
+        qemu_fdt_setprop_cell(ms->fdt, nodename, "phandle",
+                              qemu_fdt_alloc_phandle(ms->fdt));
+        g_free(nodename);
+    }
+
+    /*cpu map */
+    qemu_fdt_add_subnode(ms->fdt, "/cpus/cpu-map");
+
+    for (num = smp_cpus - 1; num >= 0; num--) {
+        char *cpu_path = g_strdup_printf("/cpus/cpu@%d", num);
+        char *map_path;
+
+        if (ms->smp.threads > 1) {
+            map_path = g_strdup_printf(
+                "/cpus/cpu-map/socket%d/core%d/thread%d",
+                num / (ms->smp.cores * ms->smp.threads),
+                (num / ms->smp.threads) % ms->smp.cores,
+                num % ms->smp.threads);
+        } else {
+            map_path = g_strdup_printf(
+                "/cpus/cpu-map/socket%d/core%d",
+                num / ms->smp.cores,
+                num % ms->smp.cores);
+        }
+        qemu_fdt_add_path(ms->fdt, map_path);
+        qemu_fdt_setprop_phandle(ms->fdt, map_path, "cpu", cpu_path);
+
+        g_free(map_path);
+        g_free(cpu_path);
+    }
+}
+
+static void fdt_add_fw_cfg_node(const LoongArchMachineState *lams)
+{
+    char *nodename;
+    hwaddr base = FW_CFG_ADDR;
+    const MachineState *ms = MACHINE(lams);
+
+    nodename = g_strdup_printf("/fw_cfg@%" PRIx64, base);
+    qemu_fdt_add_subnode(ms->fdt, nodename);
+    qemu_fdt_setprop_string(ms->fdt, nodename,
+                            "compatible", "qemu,fw-cfg-mmio");
+    qemu_fdt_setprop_sized_cells(ms->fdt, nodename, "reg",
+                                 2, base, 2, 0x8);
+    qemu_fdt_setprop(ms->fdt, nodename, "dma-coherent", NULL, 0);
+    g_free(nodename);
+}
+
+static void fdt_add_pcie_node(const LoongArchMachineState *lams)
+{
+    char *nodename;
+    hwaddr base_mmio = LS7A_PCI_MEM_BASE;
+    hwaddr size_mmio = LS7A_PCI_MEM_SIZE;
+    hwaddr base_pio = LS7A_PCI_IO_BASE;
+    hwaddr size_pio = LS7A_PCI_IO_SIZE;
+    hwaddr base_pcie = LS_PCIECFG_BASE;
+    hwaddr size_pcie = LS_PCIECFG_SIZE;
+    hwaddr base = base_pcie;
+
+    const MachineState *ms = MACHINE(lams);
+
+    nodename = g_strdup_printf("/pcie@%" PRIx64, base);
+    qemu_fdt_add_subnode(ms->fdt, nodename);
+    qemu_fdt_setprop_string(ms->fdt, nodename,
+                            "compatible", "pci-host-ecam-generic");
+    qemu_fdt_setprop_string(ms->fdt, nodename, "device_type", "pci");
+    qemu_fdt_setprop_cell(ms->fdt, nodename, "#address-cells", 3);
+    qemu_fdt_setprop_cell(ms->fdt, nodename, "#size-cells", 2);
+    qemu_fdt_setprop_cell(ms->fdt, nodename, "linux,pci-domain", 0);
+    qemu_fdt_setprop_cells(ms->fdt, nodename, "bus-range", 0,
+                           PCIE_MMCFG_BUS(LS_PCIECFG_SIZE - 1));
+    qemu_fdt_setprop(ms->fdt, nodename, "dma-coherent", NULL, 0);
+    qemu_fdt_setprop_sized_cells(ms->fdt, nodename, "reg",
+                                 2, base_pcie, 2, size_pcie);
+    qemu_fdt_setprop_sized_cells(ms->fdt, nodename, "ranges",
+                                 1, FDT_PCI_RANGE_IOPORT, 2, 
LS7A_PCI_IO_OFFSET,
+                                 2, base_pio, 2, size_pio,
+                                 1, FDT_PCI_RANGE_MMIO, 2, base_mmio,
+                                 2, base_mmio, 2, size_mmio);
+    g_free(nodename);
+    qemu_fdt_dumpdtb(ms->fdt, lams->fdt_size);
+}
+
 static void loongarch_init(MachineState *machine)
 {
     const char *cpu_model = machine->cpu_type;
@@ -474,12 +597,16 @@ static void loongarch_init(MachineState *machine)
         exit(1);
     }
 
+    create_fdt(lams);
+
     /* Init CPUs */
     for (i = 0; i < machine->smp.cpus; i++) {
         la_cpu = LOONGARCH_CPU(cpu_create(machine->cpu_type));
         loongarch_cpu_init(la_cpu, i);
     }
 
+    fdt_add_cpu_nodes(lams);
+
     if (ram_size < 1 * GiB) {
         error_report("ram_size must be greater than 1G.");
         exit(1);
@@ -519,6 +646,8 @@ static void loongarch_init(MachineState *machine)
         exit(1);
     }
 
+    fdt_add_fw_cfg_node(lams);
+
     if (kernel_filename) {
         loaderparams.ram_size = ram_size;
         loaderparams.kernel_filename = kernel_filename;
@@ -543,6 +672,13 @@ static void loongarch_init(MachineState *machine)
     lams->machine_done.notify = loongarch_machine_done;
     qemu_add_machine_init_done_notifier(&lams->machine_done);
 
+    fdt_add_pcie_node(lams);
+
+    /* load fdt */
+    MemoryRegion *fdt_rom = g_new(MemoryRegion, 1);
+    memory_region_init_rom(fdt_rom, NULL, "fdt", LA_FDT_SIZE, &error_fatal);
+    memory_region_add_subregion(get_system_memory(), LA_FDT_BASE, fdt_rom);
+    rom_add_blob_fixed("fdt", machine->fdt, lams->fdt_size, LA_FDT_BASE);
 }
 
 bool loongarch_is_acpi_enabled(LoongArchMachineState *lams)
diff --git a/include/hw/loongarch/loongarch.h b/include/hw/loongarch/loongarch.h
index 689560dcde..96dae9205f 100644
--- a/include/hw/loongarch/loongarch.h
+++ b/include/hw/loongarch/loongarch.h
@@ -42,6 +42,9 @@ struct LoongArchMachineState {
 #define LA_BIOS_BASE            0x1c000000
 #define LA_BIOS_SIZE            (4 * 1024 * 1024)
 
+#define LA_FDT_BASE             0x1c400000
+#define LA_FDT_SIZE             0x100000
+
 /* Kernels can be configured with 64KB pages */
 #define INITRD_PAGE_SIZE        (64 * KiB)
 #define INITRD_BASE             0x04000000
@@ -61,6 +64,7 @@ struct LoongArchMachineState {
     OnOffAuto   acpi;
     char        *oem_id;
     char        *oem_table_id;
+    int fdt_size;
 };
 
 #define TYPE_LOONGARCH_MACHINE  MACHINE_TYPE_NAME("virt")
diff --git a/target/loongarch/cpu.c b/target/loongarch/cpu.c
index deaa0b4f31..90106939a2 100644
--- a/target/loongarch/cpu.c
+++ b/target/loongarch/cpu.c
@@ -337,6 +337,8 @@ static void loongarch_3a5000_initfn(Object *obj)
         env->cpucfg[i] = 0x0;
     }
 
+    cpu->dtb_compatible = "loongarch,Loongson-3A5000";
+
     env->cpucfg[0] = 0x14c010;  /* PRID */
 
     uint32_t data = 0;
diff --git a/target/loongarch/cpu.h b/target/loongarch/cpu.h
index 15ea1dc43d..e1add5af39 100644
--- a/target/loongarch/cpu.h
+++ b/target/loongarch/cpu.h
@@ -360,6 +360,9 @@ struct ArchCPU {
     CPUNegativeOffsetState neg;
     CPULoongArchState env;
     QEMUTimer timer;
+
+    /* 'compatible' string for this CPU for Linux device trees */
+    const char *dtb_compatible;
 };
 
 #define TYPE_LOONGARCH_CPU "loongarch-cpu"
-- 
2.31.1