[MM] Support page MPR dynamic size

For RISC-V or dynamic address space arch in the future.

Signed-off-by: GuEe-GUI <2991707448@qq.com>

Author: GuEe-GUI

components/mm/Kconfig

@@ -1,5 +1,12 @@
 menu "Memory management"
 
+config RT_PAGE_MPR_SIZE_DYNAMIC
+    bool "Page MPR size is dynamic"
+    default n
+    help
+        Some platforms' virtual address width is not a compile-time constant
+        and must be determined dynamically at runtime.
+
 config RT_PAGE_AFFINITY_BLOCK_SIZE
     hex "Affinity block size in bytes for page management"
     default 0x1000

components/mm/mm_page.c

@@ -417,9 +417,26 @@ static inline rt_page_t addr_to_page(rt_page_t pg_start, void *addr)
 const rt_size_t shadow_mask =
     ((1ul << (RT_PAGE_MAX_ORDER + ARCH_PAGE_SHIFT - 1)) - 1);
 
-const rt_size_t rt_mpr_size = CEIL(
-    ((1ul << (ARCH_VADDR_WIDTH - ARCH_PAGE_SHIFT))) * sizeof(struct rt_page),
-    ARCH_PAGE_SIZE);
+#define MPR_SIZE CEIL( \
+        ((1ul << (ARCH_VADDR_WIDTH - ARCH_PAGE_SHIFT))) * sizeof(struct rt_page), \
+        ARCH_PAGE_SIZE)
+
+#ifdef RT_PAGE_MPR_SIZE_DYNAMIC
+/**
+ * @brief Get the size of Memory Page Region (MPR)
+ *
+ * When RT_PAGE_MPR_SIZE_DYNAMIC is enabled, MPR size is calculated at runtime
+ * for platforms where virtual address width is not a compile-time constant.
+ *
+ * @return MPR size in bytes
+ */
+const rt_size_t rt_mpr_size_dynamic(void)
+{
+    return MPR_SIZE;
+}
+#else
+const rt_size_t rt_mpr_size = MPR_SIZE;
+#endif
 
 void *rt_mpr_start;
 

components/mm/mm_page.h

@@ -70,7 +70,12 @@ typedef struct tag_region
     const char *name;
 } rt_region_t;
 
+#ifdef RT_PAGE_MPR_SIZE_DYNAMIC
+const rt_size_t rt_mpr_size_dynamic(void);
+#define rt_mpr_size rt_mpr_size_dynamic()
+#else
 extern const rt_size_t rt_mpr_size;
+#endif
 extern void *rt_mpr_start;
 
 void rt_page_init(rt_region_t reg);