hw/intc: sifive_clint: Use RISC-V CPU GPIO lines

Instead of using riscv_cpu_update_mip() let's instead use the new RISC-V
CPU GPIO lines to set the timer and soft MIP bits.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@c-sky.com>
Message-id: 946e1ef5e268b24084c7ddad84c146de62a56736.1630301632.git.alistair.francis@wdc.com

hw/intc/sifive_clint.c

@@ -28,6 +28,12 @@
 #include "hw/qdev-properties.h"
 #include "hw/intc/sifive_clint.h"
 #include "qemu/timer.h"
+#include "hw/irq.h"
+
+typedef struct sifive_clint_callback {
+    SiFiveCLINTState *s;
+    int num;
+} sifive_clint_callback;
 
 static uint64_t cpu_riscv_read_rtc(uint32_t timebase_freq)
 {
@@ -39,7 +45,9 @@ static uint64_t cpu_riscv_read_rtc(uint32_t timebase_freq)
  * Called when timecmp is written to update the QEMU timer or immediately
  * trigger timer interrupt if mtimecmp <= current timer value.
  */
-static void sifive_clint_write_timecmp(RISCVCPU *cpu, uint64_t value,
+static void sifive_clint_write_timecmp(SiFiveCLINTState *s, RISCVCPU *cpu,
+                                       int hartid,
+                                       uint64_t value,
                                        uint32_t timebase_freq)
 {
     uint64_t next;
@@ -51,12 +59,12 @@ static void sifive_clint_write_timecmp(RISCVCPU *cpu, uint64_t value,
     if (cpu->env.timecmp <= rtc_r) {
         /* if we're setting an MTIMECMP value in the "past",
            immediately raise the timer interrupt */
-        riscv_cpu_update_mip(cpu, MIP_MTIP, BOOL_TO_MASK(1));
+        qemu_irq_raise(s->timer_irqs[hartid - s->hartid_base]);
         return;
     }
 
     /* otherwise, set up the future timer interrupt */
-    riscv_cpu_update_mip(cpu, MIP_MTIP, BOOL_TO_MASK(0));
+    qemu_irq_lower(s->timer_irqs[hartid - s->hartid_base]);
     diff = cpu->env.timecmp - rtc_r;
     /* back to ns (note args switched in muldiv64) */
     uint64_t ns_diff = muldiv64(diff, NANOSECONDS_PER_SECOND, timebase_freq);
@@ -91,8 +99,9 @@ static void sifive_clint_write_timecmp(RISCVCPU *cpu, uint64_t value,
  */
 static void sifive_clint_timer_cb(void *opaque)
 {
-    RISCVCPU *cpu = opaque;
+    sifive_clint_callback *state = opaque;
-    riscv_cpu_update_mip(cpu, MIP_MTIP, BOOL_TO_MASK(1));
+
+    qemu_irq_raise(state->s->timer_irqs[state->num]);
 }
 
 /* CPU wants to read rtc or timecmp register */
@@ -158,7 +167,7 @@ static void sifive_clint_write(void *opaque, hwaddr addr, uint64_t value,
         if (!env) {
             error_report("clint: invalid timecmp hartid: %zu", hartid);
         } else if ((addr & 0x3) == 0) {
-            riscv_cpu_update_mip(RISCV_CPU(cpu), MIP_MSIP, BOOL_TO_MASK(value));
+            qemu_set_irq(clint->soft_irqs[hartid - clint->hartid_base], value);
         } else {
             error_report("clint: invalid sip write: %08x", (uint32_t)addr);
         }
@@ -174,13 +183,13 @@ static void sifive_clint_write(void *opaque, hwaddr addr, uint64_t value,
         } else if ((addr & 0x7) == 0) {
             /* timecmp_lo */
             uint64_t timecmp_hi = env->timecmp >> 32;
-            sifive_clint_write_timecmp(RISCV_CPU(cpu),
+            sifive_clint_write_timecmp(clint, RISCV_CPU(cpu), hartid,
                 timecmp_hi << 32 | (value & 0xFFFFFFFF), clint->timebase_freq);
             return;
         } else if ((addr & 0x7) == 4) {
             /* timecmp_hi */
             uint64_t timecmp_lo = env->timecmp;
-            sifive_clint_write_timecmp(RISCV_CPU(cpu),
+            sifive_clint_write_timecmp(clint, RISCV_CPU(cpu), hartid,
                 value << 32 | (timecmp_lo & 0xFFFFFFFF), clint->timebase_freq);
         } else {
             error_report("clint: invalid timecmp write: %08x", (uint32_t)addr);
@@ -226,6 +235,12 @@ static void sifive_clint_realize(DeviceState *dev, Error **errp)
     memory_region_init_io(&s->mmio, OBJECT(dev), &sifive_clint_ops, s,
                           TYPE_SIFIVE_CLINT, s->aperture_size);
     sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->mmio);
+
+    s->timer_irqs = g_malloc(sizeof(qemu_irq) * s->num_harts);
+    qdev_init_gpio_out(dev, s->timer_irqs, s->num_harts);
+
+    s->soft_irqs = g_malloc(sizeof(qemu_irq) * s->num_harts);
+    qdev_init_gpio_out(dev, s->soft_irqs, s->num_harts);
 }
 
 static void sifive_clint_class_init(ObjectClass *klass, void *data)
@@ -249,7 +264,6 @@ static void sifive_clint_register_types(void)
 
 type_init(sifive_clint_register_types)
 
-
 /*
  * Create CLINT device.
  */
@@ -259,19 +273,6 @@ DeviceState *sifive_clint_create(hwaddr addr, hwaddr size,
     bool provide_rdtime)
 {
     int i;
-    for (i = 0; i < num_harts; i++) {
-        CPUState *cpu = qemu_get_cpu(hartid_base + i);
-        CPURISCVState *env = cpu ? cpu->env_ptr : NULL;
-        if (!env) {
-            continue;
-        }
-        if (provide_rdtime) {
-            riscv_cpu_set_rdtime_fn(env, cpu_riscv_read_rtc, timebase_freq);
-        }
-        env->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
-                                  &sifive_clint_timer_cb, cpu);
-        env->timecmp = 0;
-    }
 
     DeviceState *dev = qdev_new(TYPE_SIFIVE_CLINT);
     qdev_prop_set_uint32(dev, "hartid-base", hartid_base);
@@ -283,5 +284,32 @@ DeviceState *sifive_clint_create(hwaddr addr, hwaddr size,
     qdev_prop_set_uint32(dev, "timebase-freq", timebase_freq);
     sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, addr);
+
+    for (i = 0; i < num_harts; i++) {
+        CPUState *cpu = qemu_get_cpu(hartid_base + i);
+        RISCVCPU *rvcpu = RISCV_CPU(cpu);
+        CPURISCVState *env = cpu ? cpu->env_ptr : NULL;
+        sifive_clint_callback *cb = g_malloc0(sizeof(sifive_clint_callback));
+
+        if (!env) {
+            g_free(cb);
+            continue;
+        }
+        if (provide_rdtime) {
+            riscv_cpu_set_rdtime_fn(env, cpu_riscv_read_rtc, timebase_freq);
+        }
+
+        cb->s = SIFIVE_CLINT(dev);
+        cb->num = i;
+        env->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
+                                  &sifive_clint_timer_cb, cb);
+        env->timecmp = 0;
+
+        qdev_connect_gpio_out(dev, i,
+                              qdev_get_gpio_in(DEVICE(rvcpu), IRQ_M_TIMER));
+        qdev_connect_gpio_out(dev, num_harts + i,
+                              qdev_get_gpio_in(DEVICE(rvcpu), IRQ_M_SOFT));
+    }
+
     return dev;
 }

include/hw/intc/sifive_clint.h

@@ -40,6 +40,8 @@ typedef struct SiFiveCLINTState {
     uint32_t time_base;
     uint32_t aperture_size;
     uint32_t timebase_freq;
+    qemu_irq *timer_irqs;
+    qemu_irq *soft_irqs;
 } SiFiveCLINTState;
 
 DeviceState *sifive_clint_create(hwaddr addr, hwaddr size,