[Qemu-devel] [PATCH v2 06/28] riscv: sifive_u: Update hart configuration to reflect the real FU540 SoC

[Bin Meng <bmeng.cn@gmail.com>]

The FU540-C000 includes a 64-bit E51 RISC-V core and four 64-bit U54
RISC-V cores. Currently the sifive_u machine only populates 4 U54
cores. Update the max cpu number to 5 to reflect the real hardware,
and pass "cpu-type" to populate heterogeneous harts.

The cpu nodes in the generated DTS have been updated as well.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>

---

Changes in v2:
- fixed the "interrupts-extended" property size

 hw/riscv/sifive_u.c | 40 +++++++++++++++++++++++++++++-----------
 1 file changed, 29 insertions(+), 11 deletions(-)

diff --git a/hw/riscv/sifive_u.c b/hw/riscv/sifive_u.c
index 623ee64..821f1d5 100644
--- a/hw/riscv/sifive_u.c
+++ b/hw/riscv/sifive_u.c
@@ -10,7 +10,8 @@
  * 1) CLINT (Core Level Interruptor)
  * 2) PLIC (Platform Level Interrupt Controller)
  *
- * This board currently uses a hardcoded devicetree that indicates one hart.
+ * This board currently generates devicetree dynamically that indicates at most
+ * five harts.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
@@ -26,6 +27,7 @@
  */
 
 #include "qemu/osdep.h"
+#include "qemu/cutils.h"
 #include "qemu/log.h"
 #include "qemu/error-report.h"
 #include "qapi/error.h"
@@ -117,7 +119,10 @@ static void create_fdt(SiFiveUState *s, const struct MemmapEntry *memmap,
         qemu_fdt_add_subnode(fdt, nodename);
         qemu_fdt_setprop_cell(fdt, nodename, "clock-frequency",
                               SIFIVE_U_CLOCK_FREQ);
-        qemu_fdt_setprop_string(fdt, nodename, "mmu-type", "riscv,sv48");
+        /* cpu 0 is the management hart that does not have mmu */
+        if (cpu != 0) {
+            qemu_fdt_setprop_string(fdt, nodename, "mmu-type", "riscv,sv48");
+        }
         qemu_fdt_setprop_string(fdt, nodename, "riscv,isa", isa);
         qemu_fdt_setprop_string(fdt, nodename, "compatible", "riscv");
         qemu_fdt_setprop_string(fdt, nodename, "status", "okay");
@@ -157,15 +162,21 @@ static void create_fdt(SiFiveUState *s, const struct MemmapEntry *memmap,
     g_free(nodename);
 
     plic_phandle = phandle++;
-    cells =  g_new0(uint32_t, s->soc.cpus.num_harts * 4);
+    cells =  g_new0(uint32_t, s->soc.cpus.num_harts * 4 - 2);
     for (cpu = 0; cpu < s->soc.cpus.num_harts; cpu++) {
         nodename =
             g_strdup_printf("/cpus/cpu@%d/interrupt-controller", cpu);
         uint32_t intc_phandle = qemu_fdt_get_phandle(fdt, nodename);
-        cells[cpu * 4 + 0] = cpu_to_be32(intc_phandle);
-        cells[cpu * 4 + 1] = cpu_to_be32(IRQ_M_EXT);
-        cells[cpu * 4 + 2] = cpu_to_be32(intc_phandle);
-        cells[cpu * 4 + 3] = cpu_to_be32(IRQ_S_EXT);
+        /* cpu 0 is the management hart that does not have S-mode */
+        if (cpu == 0) {
+            cells[0] = cpu_to_be32(intc_phandle);
+            cells[1] = cpu_to_be32(IRQ_M_EXT);
+        } else {
+            cells[cpu * 4 - 2] = cpu_to_be32(intc_phandle);
+            cells[cpu * 4 - 1] = cpu_to_be32(IRQ_M_EXT);
+            cells[cpu * 4 + 0] = cpu_to_be32(intc_phandle);
+            cells[cpu * 4 + 1] = cpu_to_be32(IRQ_S_EXT);
+        }
         g_free(nodename);
     }
     nodename = g_strdup_printf("/soc/interrupt-controller@%lx",
@@ -175,7 +186,7 @@ static void create_fdt(SiFiveUState *s, const struct MemmapEntry *memmap,
     qemu_fdt_setprop_string(fdt, nodename, "compatible", "riscv,plic0");
     qemu_fdt_setprop(fdt, nodename, "interrupt-controller", NULL, 0);
     qemu_fdt_setprop(fdt, nodename, "interrupts-extended",
-        cells, s->soc.cpus.num_harts * sizeof(uint32_t) * 4);
+        cells, (s->soc.cpus.num_harts * 4 - 2) * sizeof(uint32_t));
     qemu_fdt_setprop_cells(fdt, nodename, "reg",
         0x0, memmap[SIFIVE_U_PLIC].base,
         0x0, memmap[SIFIVE_U_PLIC].size);
@@ -315,10 +326,16 @@ static void riscv_sifive_u_soc_init(Object *obj)
 {
     MachineState *ms = MACHINE(qdev_get_machine());
     SiFiveUSoCState *s = RISCV_U_SOC(obj);
+    char cpu_type[64];
+
+    /* create cpu type representing SiFive FU540 SoC */
+    pstrcpy(cpu_type, sizeof(cpu_type), SIFIVE_E_CPU);
+    pstrcat(cpu_type, sizeof(cpu_type), ",");
+    pstrcat(cpu_type, sizeof(cpu_type), SIFIVE_U_CPU);
 
     object_initialize_child(obj, "cpus", &s->cpus, sizeof(s->cpus),
                             TYPE_RISCV_HART_ARRAY, &error_abort, NULL);
-    object_property_set_str(OBJECT(&s->cpus), SIFIVE_U_CPU, "cpu-type",
+    object_property_set_str(OBJECT(&s->cpus), cpu_type, "cpu-type",
                             &error_abort);
     object_property_set_int(OBJECT(&s->cpus), ms->smp.cpus, "num-harts",
                             &error_abort);
@@ -407,10 +424,11 @@ static void riscv_sifive_u_machine_init(MachineClass *mc)
 {
     mc->desc = "RISC-V Board compatible with SiFive U SDK";
     mc->init = riscv_sifive_u_init;
-    /* The real hardware has 5 CPUs, but one of them is a small embedded power
+    /*
+     * The real hardware has 5 CPUs, but one of them is a small embedded power
      * management CPU.
      */
-    mc->max_cpus = 4;
+    mc->max_cpus = 5;
 }
 
 DEFINE_MACHINE("sifive_u", riscv_sifive_u_machine_init)
-- 
2.7.4