hw/riscv: Allow creating multiple instances of PLIC

We extend PLIC emulation to allow multiple instances of PLIC in
a QEMU RISC-V machine. To achieve this, we remove first HART id
zero assumption from PLIC emulation.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20200616032229.766089-3-anup.patel@wdc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

4 files changed, 16 insertions, 14 deletions

diff --git a/hw/riscv/sifive_e.c b/hw/riscv/sifive_e.c
index 01f661d..ca55cc4 100644
--- a/hw/riscv/sifive_e.c
+++ b/hw/riscv/sifive_e.c
@@ -200,7 +200,7 @@ static void sifive_e_soc_realize(DeviceState *dev, Error **errp)
 
     /* MMIO */
     s->plic = sifive_plic_create(memmap[SIFIVE_E_PLIC].base,
-        (char *)SIFIVE_E_PLIC_HART_CONFIG,
+        (char *)SIFIVE_E_PLIC_HART_CONFIG, 0,
         SIFIVE_E_PLIC_NUM_SOURCES,
         SIFIVE_E_PLIC_NUM_PRIORITIES,
         SIFIVE_E_PLIC_PRIORITY_BASE,
diff --git a/hw/riscv/sifive_plic.c b/hw/riscv/sifive_plic.c
index c20c192..11ef147 100644
--- a/hw/riscv/sifive_plic.c
+++ b/hw/riscv/sifive_plic.c
@@ -361,6 +361,7 @@ static const MemoryRegionOps sifive_plic_ops = {
 
 static Property sifive_plic_properties[] = {
     DEFINE_PROP_STRING("hart-config", SiFivePLICState, hart_config),
+    DEFINE_PROP_UINT32("hartid-base", SiFivePLICState, hartid_base, 0),
     DEFINE_PROP_UINT32("num-sources", SiFivePLICState, num_sources, 0),
     DEFINE_PROP_UINT32("num-priorities", SiFivePLICState, num_priorities, 0),
     DEFINE_PROP_UINT32("priority-base", SiFivePLICState, priority_base, 0),
@@ -409,10 +410,12 @@ static void parse_hart_config(SiFivePLICState *plic)
     }
     hartid++;
 
-    /* store hart/mode combinations */
     plic->num_addrs = addrid;
+    plic->num_harts = hartid;
+
+    /* store hart/mode combinations */
     plic->addr_config = g_new(PLICAddr, plic->num_addrs);
-    addrid = 0, hartid = 0;
+    addrid = 0, hartid = plic->hartid_base;
     p = plic->hart_config;
     while ((c = *p++)) {
         if (c == ',') {
@@ -438,8 +441,6 @@ static void sifive_plic_irq_request(void *opaque, int irq, int level)
 
 static void sifive_plic_realize(DeviceState *dev, Error **errp)
 {
-    MachineState *ms = MACHINE(qdev_get_machine());
-    unsigned int smp_cpus = ms->smp.cpus;
     SiFivePLICState *plic = SIFIVE_PLIC(dev);
     int i;
 
@@ -460,8 +461,8 @@ static void sifive_plic_realize(DeviceState *dev, Error **errp)
      * lost a interrupt in the case a PLIC is attached. The SEIP bit must be
      * hardware controlled when a PLIC is attached.
      */
-    for (i = 0; i < smp_cpus; i++) {
-        RISCVCPU *cpu = RISCV_CPU(qemu_get_cpu(i));
+    for (i = 0; i < plic->num_harts; i++) {
+        RISCVCPU *cpu = RISCV_CPU(qemu_get_cpu(plic->hartid_base + i));
         if (riscv_cpu_claim_interrupts(cpu, MIP_SEIP) < 0) {
             error_report("SEIP already claimed");
             exit(1);
@@ -497,16 +498,17 @@ type_init(sifive_plic_register_types)
  * Create PLIC device.
  */
 DeviceState *sifive_plic_create(hwaddr addr, char *hart_config,
-    uint32_t num_sources, uint32_t num_priorities,
-    uint32_t priority_base, uint32_t pending_base,
-    uint32_t enable_base, uint32_t enable_stride,
-    uint32_t context_base, uint32_t context_stride,
-    uint32_t aperture_size)
+    uint32_t hartid_base, uint32_t num_sources,
+    uint32_t num_priorities, uint32_t priority_base,
+    uint32_t pending_base, uint32_t enable_base,
+    uint32_t enable_stride, uint32_t context_base,
+    uint32_t context_stride, uint32_t aperture_size)
 {
     DeviceState *dev = qdev_new(TYPE_SIFIVE_PLIC);
     assert(enable_stride == (enable_stride & -enable_stride));
     assert(context_stride == (context_stride & -context_stride));
     qdev_prop_set_string(dev, "hart-config", hart_config);
+    qdev_prop_set_uint32(dev, "hartid-base", hartid_base);
     qdev_prop_set_uint32(dev, "num-sources", num_sources);
     qdev_prop_set_uint32(dev, "num-priorities", num_priorities);
     qdev_prop_set_uint32(dev, "priority-base", priority_base);
diff --git a/hw/riscv/sifive_u.c b/hw/riscv/sifive_u.c
index 8d2ee9d..a48046c 100644
--- a/hw/riscv/sifive_u.c
+++ b/hw/riscv/sifive_u.c
@@ -687,7 +687,7 @@ static void sifive_u_soc_realize(DeviceState *dev, Error **errp)
 
     /* MMIO */
     s->plic = sifive_plic_create(memmap[SIFIVE_U_PLIC].base,
-        plic_hart_config,
+        plic_hart_config, 0,
         SIFIVE_U_PLIC_NUM_SOURCES,
         SIFIVE_U_PLIC_NUM_PRIORITIES,
         SIFIVE_U_PLIC_PRIORITY_BASE,
diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c
index 69cfca8..8a66f43 100644
--- a/hw/riscv/virt.c
+++ b/hw/riscv/virt.c
@@ -560,7 +560,7 @@ static void virt_machine_init(MachineState *machine)
 
     /* MMIO */
     s->plic = sifive_plic_create(memmap[VIRT_PLIC].base,
-        plic_hart_config,
+        plic_hart_config, 0,
         VIRT_PLIC_NUM_SOURCES,
         VIRT_PLIC_NUM_PRIORITIES,
         VIRT_PLIC_PRIORITY_BASE,