From: Mayuresh Chitale <mchitale@ventanamicro.com>

The trace encoder and trace ramsink nodes should confirm to the bindings
described in "riscv,trace-component.yaml" in the Linux kernel. That way,
encoder and ramsink devices get populated on the rvtrace bus and perf
record is able to capture the trace data in the auxtrace section as
expected.

Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
---
 hw/riscv/virt.c | 58 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c
index b1a4d63efd..30e89a6c5a 100644
--- a/hw/riscv/virt.c
+++ b/hw/riscv/virt.c
@@ -1142,6 +1142,62 @@ static void create_fdt_iommu(RISCVVirtState *s, uint16_t bdf)
     s->pci_iommu_bdf = bdf;
 }
 
+static void create_fdt_rvtrace(RISCVVirtState *s)
+{
+    static const char * const tr_compat[2] = { "qemu,trace-component",
+                                               "riscv,trace-component" };
+    g_autofree char *cpu_name = NULL, *ram_sink_name = NULL,
+                    *trencoder_name = NULL, *ep = NULL;
+    MachineState *ms = MACHINE(s);
+    int socket_count = riscv_socket_count(ms), i;
+    uint64_t addr, size = 0x100;
+    uint32_t rs_phandle;
+    RISCVCPU *cpu_ptr;
+
+
+    for (i = 0; i < socket_count; i++) {
+        for (int cpu = 0; cpu < s->soc[i].num_harts; cpu++) {
+            cpu_ptr = &s->soc[i].harts[cpu];
+            if (!cpu_ptr->trencoder) {
+                continue;
+            }
+            cpu_name = g_strdup_printf("/cpus/cpu@%d",
+                                       s->soc[i].hartid_base + cpu);
+            ram_sink_name = g_strdup_printf("/soc/ramsink@%d",
+                                            s->soc[i].hartid_base + cpu);
+            qemu_fdt_add_subnode(ms->fdt, ram_sink_name);
+            addr = object_property_get_uint(cpu_ptr->trencoder, "dest-baseaddr",
+                                            &error_abort);
+            qemu_fdt_setprop_sized_cells(ms->fdt, ram_sink_name, "reg", 2, addr,
+                                         2, size);
+            qemu_fdt_setprop_string_array(ms->fdt, ram_sink_name, "compatible",
+                                          (char **)&tr_compat,
+                                          ARRAY_SIZE(tr_compat));
+            qemu_fdt_setprop_phandle(ms->fdt, ram_sink_name, "cpu", cpu_name);
+            ep = g_strdup_printf("%s/in-ports/port/endpoint", ram_sink_name);
+            qemu_fdt_add_path(ms->fdt, ep);
+            rs_phandle = qemu_fdt_alloc_phandle(ms->fdt);
+            qemu_fdt_setprop_cell(ms->fdt, ep, "phandle", rs_phandle);
+
+
+            trencoder_name = g_strdup_printf("/soc/encoder@%d",
+                                             s->soc[i].hartid_base + cpu);
+            qemu_fdt_add_subnode(ms->fdt, trencoder_name);
+            addr = object_property_get_uint(cpu_ptr->trencoder, "baseaddr",
+                                            &error_abort);
+            qemu_fdt_setprop_sized_cells(ms->fdt, trencoder_name, "reg", 2,
+                                         addr, 2, size);
+            qemu_fdt_setprop_string_array(ms->fdt, trencoder_name, "compatible",
+                                          (char **)&tr_compat,
+                                          ARRAY_SIZE(tr_compat));
+            qemu_fdt_setprop_phandle(ms->fdt, trencoder_name, "cpus", cpu_name);
+            ep = g_strdup_printf("%s/out-ports/port/endpoint", trencoder_name);
+            qemu_fdt_add_path(ms->fdt, ep);
+            qemu_fdt_setprop_cell(ms->fdt, ep, "remote-endpoint", rs_phandle);
+        }
+    }
+}
+
 static void finalize_fdt(RISCVVirtState *s)
 {
     uint32_t phandle = 1, irq_mmio_phandle = 1, msi_pcie_phandle = 1;
@@ -1166,6 +1222,8 @@ static void finalize_fdt(RISCVVirtState *s)
     create_fdt_uart(s, irq_mmio_phandle);
 
     create_fdt_rtc(s, irq_mmio_phandle);
+
+    create_fdt_rvtrace(s);
 }
 
 static void create_fdt(RISCVVirtState *s)
-- 
2.51.1