RT-Thread · Tm-C-mT · Oct 28, 2025 · Oct 28, 2025 · Oct 28, 2025 · Oct 28, 2025
diff --git a/bsp/qemu-virt64-riscv/SConstruct b/bsp/qemu-virt64-riscv/SConstruct
@@ -38,5 +38,25 @@ if GetDepend('__STACKSIZE__'): stack_size = GetDepend('__STACKSIZE__')
 stack_lds.write('__STACKSIZE__ = %d;\n' % stack_size)
 stack_lds.close()
 
+# Obtain the number of harts from rtconfig.h and write 
+# it into link_cpus.lds for the linker script
+try:
+    with open('rtconfig.h', 'r') as f:
+        rtconfig_content = f.readlines()
+except FileNotFoundError:
+    cpus_nr = 1
+else:
+    cpus_nr = 1  # default value
+    for line in rtconfig_content:
+        line = line.strip()
+        if line.startswith('#define') and 'RT_CPUS_NR' in line:
+            parts = line.split()
+            if len(parts) >= 3 and parts[2].isdigit():
+                cpus_nr = int(parts[2])
+                break 
+
+with open('link_cpus.lds', 'w') as cpus_lds:
+    cpus_lds.write(f'RT_CPUS_NR = {cpus_nr};\n')
+
 # make a building
 DoBuilding(TARGET, objs)
diff --git a/bsp/qemu-virt64-riscv/driver/board.c b/bsp/qemu-virt64-riscv/driver/board.c
@@ -89,6 +89,11 @@ void rt_hw_board_init(void)
 
     rt_hw_tick_init();
 
+#ifdef RT_USING_SMP
+    /* ipi init */
+    rt_hw_ipi_init();
+#endif /* RT_USING_SMP */
+
 #ifdef RT_USING_COMPONENTS_INIT
     rt_components_board_init();
 #endif

diff --git a/bsp/qemu-virt64-riscv/link.lds b/bsp/qemu-virt64-riscv/link.lds
@@ -9,6 +9,7 @@
  */
 
 INCLUDE "link_stacksize.lds"
+INCLUDE "link_cpus.lds"
 
 OUTPUT_ARCH( "riscv" )
 
@@ -121,12 +122,9 @@ SECTIONS
     {
         . = ALIGN(64);
         __stack_start__ = .;
-
-        . += __STACKSIZE__;
-        __stack_cpu0 = .;
-
-        . += __STACKSIZE__;
-        __stack_cpu1 = .;
+        /* Dynamically allocate stack areas according to RT_CPUS_NR */
+        . += (__STACKSIZE__ * RT_CPUS_NR);
+        __stack_end__ = .;
     } > SRAM
 
     .sbss :

diff --git a/bsp/qemu-virt64-riscv/link_cpus.lds b/bsp/qemu-virt64-riscv/link_cpus.lds
@@ -0,0 +1 @@
+RT_CPUS_NR = 8;
diff --git a/bsp/qemu-virt64-riscv/qemu-dbg.sh b/bsp/qemu-virt64-riscv/qemu-dbg.sh
@@ -1,4 +1,16 @@
-qemu-system-riscv64 -nographic -machine virt -m 256M -kernel rtthread.bin -s -S \
+QEMU_CMD="qemu-system-riscv64 -nographic -machine virt -m 256M -kernel rtthread.bin -s -S"
+
+if grep -q "#define RT_USING_SMP" ./rtconfig.h 2>/dev/null; then
+    hart_num=$(grep "RT_CPUS_NR = [0-9]*;" ./link_cpus.lds | awk -F'[=;]' '{gsub(/ /, "", $2); print $2}')
+    if [ -z "$hart_num" ]; then
+        hart_num=1
+    fi
+    QEMU_CMD="$QEMU_CMD -smp $hart_num"
+fi
+
+QEMU_CMD="$QEMU_CMD \
 -drive if=none,file=sd.bin,format=raw,id=blk0 -device virtio-blk-device,drive=blk0,bus=virtio-mmio-bus.0 \
 -netdev user,id=tap0 -device virtio-net-device,netdev=tap0,bus=virtio-mmio-bus.1 \
--device virtio-serial-device -chardev socket,host=127.0.0.1,port=4321,server=on,wait=off,telnet=on,id=console0 -device virtserialport,chardev=console0
+-device virtio-serial-device -chardev socket,host=127.0.0.1,port=4321,server=on,wait=off,telnet=on,id=console0 -device virtserialport,chardev=console0"
+
+eval $QEMU_CMD
diff --git a/bsp/qemu-virt64-riscv/run.sh b/bsp/qemu-virt64-riscv/run.sh
@@ -24,7 +24,19 @@ if [ ! -f $path_image ]; then
 	exit
 fi
 
-qemu-system-riscv64 -nographic -machine virt -m 256M -kernel rtthread.bin \
+QEMU_CMD="qemu-system-riscv64 -nographic -machine virt -m 256M -kernel rtthread.bin"
+
+if grep -q "#define RT_USING_SMP" ./rtconfig.h 2>/dev/null; then
+    hart_num=$(grep "RT_CPUS_NR = [0-9]*;" ./link_cpus.lds | awk -F'[=;]' '{gsub(/ /, "", $2); print $2}')
+    if [ -z "$hart_num" ]; then
+        hart_num=1
+    fi
+    QEMU_CMD="$QEMU_CMD -smp $hart_num"
+fi
+
+QEMU_CMD="$QEMU_CMD \
 -drive if=none,file=$path_image,format=raw,id=blk0 -device virtio-blk-device,drive=blk0,bus=virtio-mmio-bus.0 \
 -netdev user,id=tap0 -device virtio-net-device,netdev=tap0,bus=virtio-mmio-bus.1 \
--device virtio-serial-device -chardev socket,host=127.0.0.1,port=4321,server=on,wait=off,telnet=on,id=console0 -device virtserialport,chardev=console0
+-device virtio-serial-device -chardev socket,host=127.0.0.1,port=4321,server=on,wait=off,telnet=on,id=console0 -device virtserialport,chardev=console0"
+
+eval $QEMU_CMD
diff --git a/libcpu/risc-v/common64/atomic_riscv.c b/libcpu/risc-v/common64/atomic_riscv.c
@@ -0,0 +1,159 @@
+/*
+ * Copyright (c) 2006-2023, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2023-03-14     WangShun     first version
+ */
+
+#include <rtthread.h>
+
+rt_atomic_t rt_hw_atomic_exchange(volatile rt_atomic_t *ptr, rt_atomic_t val)
+{
+    rt_atomic_t result = 0;
+#if __riscv_xlen == 32
+    asm volatile("amoswap.w %0, %1, (%2)" : "=r"(result) : "r"(val), "r"(ptr) : "memory");
+#elif __riscv_xlen == 64
+    asm volatile("amoswap.d %0, %1, (%2)" : "=r"(result) : "r"(val), "r"(ptr) : "memory");
+#endif
+    return result;
+}
+
+rt_atomic_t rt_hw_atomic_add(volatile rt_atomic_t *ptr, rt_atomic_t val)
+{
+    rt_atomic_t result = 0;
+#if __riscv_xlen == 32
+    asm volatile("amoadd.w %0, %1, (%2)" : "=r"(result) : "r"(val), "r"(ptr) : "memory");
+#elif __riscv_xlen == 64
+    asm volatile("amoadd.d %0, %1, (%2)" : "=r"(result) : "r"(val), "r"(ptr) : "memory");
+#endif
+    return result;
+}
+
+rt_atomic_t rt_hw_atomic_sub(volatile rt_atomic_t *ptr, rt_atomic_t val)
+{
+    rt_atomic_t result = 0;
+    val = -val;
+#if __riscv_xlen == 32
+    asm volatile("amoadd.w %0, %1, (%2)" : "=r"(result) : "r"(val), "r"(ptr) : "memory");
+#elif __riscv_xlen == 64
+    asm volatile("amoadd.d %0, %1, (%2)" : "=r"(result) : "r"(val), "r"(ptr) : "memory");
+#endif
+    return result;
+}
+
+rt_atomic_t rt_hw_atomic_xor(volatile rt_atomic_t *ptr, rt_atomic_t val)
+{
+    rt_atomic_t result = 0;
+#if __riscv_xlen == 32
+    asm volatile("amoxor.w %0, %1, (%2)" : "=r"(result) : "r"(val), "r"(ptr) : "memory");
+#elif __riscv_xlen == 64
+    asm volatile("amoxor.d %0, %1, (%2)" : "=r"(result) : "r"(val), "r"(ptr) : "memory");
+#endif
+    return result;
+}
+
+rt_atomic_t rt_hw_atomic_and(volatile rt_atomic_t *ptr, rt_atomic_t val)
+{
+    rt_atomic_t result = 0;
+#if __riscv_xlen == 32
+    asm volatile("amoand.w %0, %1, (%2)" : "=r"(result) : "r"(val), "r"(ptr) : "memory");
+#elif __riscv_xlen == 64
+    asm volatile("amoand.d %0, %1, (%2)" : "=r"(result) : "r"(val), "r"(ptr) : "memory");
+#endif
+    return result;
+}
+
+rt_atomic_t rt_hw_atomic_or(volatile rt_atomic_t *ptr, rt_atomic_t val)
+{
+    rt_atomic_t result = 0;
+#if __riscv_xlen == 32
+    asm volatile("amoor.w %0, %1, (%2)" : "=r"(result) : "r"(val), "r"(ptr) : "memory");
+#elif __riscv_xlen == 64
+    asm volatile("amoor.d %0, %1, (%2)" : "=r"(result) : "r"(val), "r"(ptr) : "memory");
+#endif
+    return result;
+}
+
+rt_atomic_t rt_hw_atomic_load(volatile rt_atomic_t *ptr)
+{
+    rt_atomic_t result = 0;
+#if __riscv_xlen == 32
+    asm volatile("amoxor.w %0, x0, (%1)" : "=r"(result) : "r"(ptr) : "memory");
+#elif __riscv_xlen == 64
+    asm volatile("amoxor.d %0, x0, (%1)" : "=r"(result) : "r"(ptr) : "memory");
+#endif
+    return result;
+}
+
+void rt_hw_atomic_store(volatile rt_atomic_t *ptr, rt_atomic_t val)
+{
+    rt_atomic_t result = 0;
+#if __riscv_xlen == 32
+    asm volatile("amoswap.w %0, %1, (%2)" : "=r"(result) : "r"(val), "r"(ptr) : "memory");
+#elif __riscv_xlen == 64
+    asm volatile("amoswap.d %0, %1, (%2)" : "=r"(result) : "r"(val), "r"(ptr) : "memory");
+#endif
+}
+
+rt_atomic_t rt_hw_atomic_flag_test_and_set(volatile rt_atomic_t *ptr)
+{
+    rt_atomic_t result = 0;
+    rt_atomic_t temp = 1;
+#if __riscv_xlen == 32
+    asm volatile("amoor.w %0, %1, (%2)" : "=r"(result) : "r"(temp), "r"(ptr) : "memory");
+#elif __riscv_xlen == 64
+    asm volatile("amoor.d %0, %1, (%2)" : "=r"(result) : "r"(temp), "r"(ptr) : "memory");
+#endif
+    return result;
+}
+
+void rt_hw_atomic_flag_clear(volatile rt_atomic_t *ptr)
+{
+    rt_atomic_t result = 0;
+#if __riscv_xlen == 32
+    asm volatile("amoand.w %0, x0, (%1)" : "=r"(result) : "r"(ptr) : "memory");
+#elif __riscv_xlen == 64
+    asm volatile("amoand.d %0, x0, (%1)" : "=r"(result) : "r"(ptr) : "memory");
+#endif
+}
+
+rt_atomic_t rt_hw_atomic_compare_exchange_strong(volatile rt_atomic_t *ptr, rt_atomic_t *old, rt_atomic_t desired)
+{
+    rt_atomic_t tmp = *old;
+    rt_atomic_t result = 0;
+#if __riscv_xlen == 32
+    asm volatile(
+        " fence iorw, ow\n"
+        "1: lr.w.aq  %[result], (%[ptr])\n"
+        "   bne      %[result], %[tmp], 2f\n"
+        "   sc.w.rl  %[tmp], %[desired], (%[ptr])\n"
+        "   bnez     %[tmp], 1b\n"
+        "   li  %[result], 1\n"
+        "   j 3f\n"
+        " 2:sw  %[result], (%[old])\n"
+        "   li  %[result], 0\n"
+        " 3:\n"
+        : [result] "+r"(result), [tmp] "+r"(tmp), [ptr] "+r"(ptr)
+        : [desired] "r"(desired), [old] "r"(old)
+        : "memory");
+#elif __riscv_xlen == 64
+    asm volatile(
+        " fence iorw, ow\n"
+        "1: lr.d.aq  %[result], (%[ptr])\n"
+        "   bne      %[result], %[tmp], 2f\n"
+        "   sc.d.rl  %[tmp], %[desired], (%[ptr])\n"
+        "   bnez     %[tmp], 1b\n"
+        "   li  %[result], 1\n"
+        "   j 3f\n"
+        " 2:sd  %[result], (%[old])\n"
+        "   li  %[result], 0\n"
+        " 3:\n"
+        : [result] "+r"(result), [tmp] "+r"(tmp), [ptr] "+r"(ptr)
+        : [desired] "r"(desired), [old] "r"(old)
+        : "memory");
+#endif
+    return result;
+}
diff --git a/libcpu/risc-v/common64/context_gcc.S b/libcpu/risc-v/common64/context_gcc.S
@@ -69,14 +69,27 @@
 .endm
 
 /*
+ * #ifdef RT_USING_SMP
+ * void rt_hw_context_switch_to(rt_ubase_t to, stuct rt_thread *to_thread);
+ * #else
  * void rt_hw_context_switch_to(rt_ubase_t to);
- *
- * a0 --> to SP pointer
+ * #endif
+ * a0 --> to
+ * a1 --> to_thread
  */
 .globl rt_hw_context_switch_to
 rt_hw_context_switch_to:
     LOAD sp, (a0)
 
+#ifdef RT_USING_SMP
+    /*
+     * Pass the previous CPU lock status to 
+     * rt_cpus_lock_status_restore for restoration 
+     */ 
+    mv   a0,   a1
+    call  rt_cpus_lock_status_restore
+#endif
+
     call rt_thread_self
     mv s1, a0
 
@@ -88,10 +101,15 @@ rt_hw_context_switch_to:
     sret
 
 /*
+ * #ifdef RT_USING_SMP
+ * void rt_hw_context_switch(rt_ubase_t from, rt_ubase_t to, struct rt_thread *to_thread);
+ * #else
  * void rt_hw_context_switch(rt_ubase_t from, rt_ubase_t to);
+ * #endif
  *
  * a0 --> from SP pointer
  * a1 --> to SP pointer
+ * a2 --> to_thread
  *
  * It should only be used on local interrupt disable
  */
@@ -103,6 +121,15 @@ rt_hw_context_switch:
     // restore to thread SP
     LOAD sp, (a1)
 
+#ifdef RT_USING_SMP
+    /*
+     * Pass the previous CPU lock status to 
+     * rt_cpus_lock_status_restore for restoration 
+     */ 
+    mv   a0,   a2
+    call  rt_cpus_lock_status_restore
+#endif /*RT_USING_SMP*/
+
     // restore Address Space
     call rt_thread_self
     mv s1, a0