[Qemu-devel] [PATCH v2 10/11] hw/mips_malta: add CPS to Malta board

[Leon Alrae]

If the user specifies smp > 1 and the CPU with CM GCR support, then
create Coherent Processing System (which takes care of instantiating CPUs)
rather than CPUs directly and connect i8259 and cbus to the pins exposed by
CPS. However, there is no GIC yet, thus CPS exposes CPU's IRQ pins so use
the same pin numbers as before.

Signed-off-by: Leon Alrae <address@hidden>
---
 hw/mips/mips_malta.c    | 60 ++++++++++++++++++++++++++++++++++++++++---------
 target-mips/cpu.h       |  1 +
 target-mips/translate.c | 10 +++++++++
 3 files changed, 60 insertions(+), 11 deletions(-)

diff --git a/hw/mips/mips_malta.c b/hw/mips/mips_malta.c
index 9e8b9ce..c26e953 100644
--- a/hw/mips/mips_malta.c
+++ b/hw/mips/mips_malta.c
@@ -55,6 +55,7 @@
 #include "hw/empty_slot.h"
 #include "sysemu/kvm.h"
 #include "exec/semihost.h"
+#include "hw/mips/cps.h"
 
 //#define DEBUG_BOARD_INIT
 
@@ -93,6 +94,7 @@ typedef struct {
 typedef struct {
     SysBusDevice parent_obj;
 
+    MIPSCPSState *cps;
     qemu_irq *i8259;
 } MaltaState;
 
@@ -906,19 +908,12 @@ static void main_cpu_reset(void *opaque)
     }
 }
 
-static void create_cpu(const char *cpu_model,
-                       qemu_irq *cbus_irq, qemu_irq *i8259_irq)
+static void create_cpu_without_cps(const char *cpu_model,
+                                   qemu_irq *cbus_irq, qemu_irq *i8259_irq)
 {
     CPUMIPSState *env;
     MIPSCPU *cpu;
     int i;
-    if (cpu_model == NULL) {
-#ifdef TARGET_MIPS64
-        cpu_model = "20Kc";
-#else
-        cpu_model = "24Kf";
-#endif
-    }
 
     for (i = 0; i < smp_cpus; i++) {
         cpu = cpu_mips_init(cpu_model);
@@ -940,6 +935,49 @@ static void create_cpu(const char *cpu_model,
     *cbus_irq = env->irq[4];
 }
 
+static void create_cps(MaltaState *s, const char *cpu_model,
+                       qemu_irq *cbus_irq, qemu_irq *i8259_irq)
+{
+    Error *err = NULL;
+    s->cps = g_new0(MIPSCPSState, 1);
+
+    object_initialize(s->cps, sizeof(MIPSCPSState), TYPE_MIPS_CPS);
+    qdev_set_parent_bus(DEVICE(s->cps), sysbus_get_default());
+
+    object_property_set_str(OBJECT(s->cps), cpu_model, "cpu-model", &err);
+    object_property_set_int(OBJECT(s->cps), smp_cpus, "num-vp", &err);
+    object_property_set_bool(OBJECT(s->cps), true, "realized", &err);
+    if (err != NULL) {
+        error_report("%s", error_get_pretty(err));
+        exit(1);
+    }
+
+    sysbus_mmio_map_overlap(SYS_BUS_DEVICE(s->cps), 0, 0, 1);
+
+    /* FIXME: When GIC is present then we should use GIC's IRQ 3.
+       Until then CPS exposes CPU's IRQs thus use the default IRQ 2. */
+    *i8259_irq = get_cps_irq(s->cps, 2);
+    *cbus_irq = NULL;
+}
+
+static void create_cpu(MaltaState *s, const char *cpu_model,
+                       qemu_irq *cbus_irq, qemu_irq *i8259_irq)
+{
+    if (cpu_model == NULL) {
+#ifdef TARGET_MIPS64
+        cpu_model = "20Kc";
+#else
+        cpu_model = "24Kf";
+#endif
+    }
+
+    if ((smp_cpus > 1) && cpu_supports_cps_smp(cpu_model)) {
+        create_cps(s, cpu_model, cbus_irq, i8259_irq);
+    } else {
+        create_cpu_without_cps(cpu_model, cbus_irq, i8259_irq);
+    }
+}
+
 static
 void mips_malta_init(MachineState *machine)
 {
@@ -992,8 +1030,8 @@ void mips_malta_init(MachineState *machine)
         }
     }
 
-    /* create CPUs */
-    create_cpu(machine->cpu_model, &cbus_irq, &i8259_irq);
+    /* create CPU */
+    create_cpu(s, machine->cpu_model, &cbus_irq, &i8259_irq);
 
     /* allocate RAM */
     if (ram_size > (2048u << 20)) {
diff --git a/target-mips/cpu.h b/target-mips/cpu.h
index 55d3224..63fea67 100644
--- a/target-mips/cpu.h
+++ b/target-mips/cpu.h
@@ -760,6 +760,7 @@ MIPSCPU *cpu_mips_init(const char *cpu_model);
 int cpu_mips_signal_handler(int host_signum, void *pinfo, void *puc);
 
 #define cpu_init(cpu_model) CPU(cpu_mips_init(cpu_model))
+bool cpu_supports_cps_smp(const char *cpu_model);
 
 /* TODO QOM'ify CPU reset and remove */
 void cpu_state_reset(CPUMIPSState *s);
diff --git a/target-mips/translate.c b/target-mips/translate.c
index 8191b92..a5b8805 100644
--- a/target-mips/translate.c
+++ b/target-mips/translate.c
@@ -19977,6 +19977,16 @@ MIPSCPU *cpu_mips_init(const char *cpu_model)
     return cpu;
 }
 
+bool cpu_supports_cps_smp(const char *cpu_model)
+{
+    const mips_def_t *def = cpu_mips_find_by_name(cpu_model);
+    if (!def) {
+        return false;
+    }
+
+    return (def->CP0_Config3 & (1 << CP0C3_CMGCR)) != 0;
+}
+
 void cpu_state_reset(CPUMIPSState *env)
 {
     MIPSCPU *cpu = mips_env_get_cpu(env);
-- 
2.1.0