diff --git a/arch/riscv/include/asm/page.h b/arch/riscv/include/asm/page.h
index 86048c60f7002..fd861ac47a890 100644
--- a/arch/riscv/include/asm/page.h
+++ b/arch/riscv/include/asm/page.h
@@ -115,6 +115,7 @@ struct kernel_mapping {
 
 extern struct kernel_mapping kernel_map;
 extern phys_addr_t phys_ram_base;
+extern unsigned long vmemmap_start_pfn;
 
 #define is_kernel_mapping(x)	\
 	((x) >= kernel_map.virt_addr && (x) < (kernel_map.virt_addr + kernel_map.size))
diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index 7d1688f850c31..bb19a643c5c2a 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -79,7 +79,7 @@
  * Define vmemmap for pfn_to_page & page_to_pfn calls. Needed if kernel
  * is configured with CONFIG_SPARSEMEM_VMEMMAP enabled.
  */
-#define vmemmap		((struct page *)VMEMMAP_START - (phys_ram_base >> PAGE_SHIFT))
+#define vmemmap		((struct page *)VMEMMAP_START - vmemmap_start_pfn)
 
 #define PCI_IO_SIZE      SZ_16M
 #define PCI_IO_END       VMEMMAP_START
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index ba2210b553f9c..72b3462babbf9 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -22,6 +22,7 @@
 #include <linux/hugetlb.h>
 
 #include <asm/fixmap.h>
+#include <asm/sparsemem.h>
 #include <asm/tlbflush.h>
 #include <asm/sections.h>
 #include <asm/soc.h>
@@ -52,6 +53,13 @@ EXPORT_SYMBOL(pgtable_l5_enabled);
 phys_addr_t phys_ram_base __ro_after_init;
 EXPORT_SYMBOL(phys_ram_base);
 
+#ifdef CONFIG_SPARSEMEM_VMEMMAP
+#define VMEMMAP_ADDR_ALIGN	(1ULL << SECTION_SIZE_BITS)
+
+unsigned long vmemmap_start_pfn __ro_after_init;
+EXPORT_SYMBOL(vmemmap_start_pfn);
+#endif
+
 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
 							__page_aligned_bss;
 EXPORT_SYMBOL(empty_zero_page);
@@ -210,8 +218,12 @@ static void __init setup_bootmem(void)
 	memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start);
 
 	phys_ram_end = memblock_end_of_DRAM();
-	if (!IS_ENABLED(CONFIG_XIP_KERNEL))
+	if (!IS_ENABLED(CONFIG_XIP_KERNEL)) {
 		phys_ram_base = memblock_start_of_DRAM();
+#ifdef CONFIG_SPARSEMEM_VMEMMAP
+		vmemmap_start_pfn = round_down(phys_ram_base, VMEMMAP_ADDR_ALIGN) >> PAGE_SHIFT;
+#endif
+}
 	/*
 	 * Reserve physical address space that would be mapped to virtual
 	 * addresses greater than (void *)(-PAGE_SIZE) because:
@@ -946,6 +958,9 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa)
 	kernel_map.xiprom_sz = (uintptr_t)(&_exiprom) - (uintptr_t)(&_xiprom);
 
 	phys_ram_base = CONFIG_PHYS_RAM_BASE;
+#ifdef CONFIG_SPARSEMEM_VMEMMAP
+	vmemmap_start_pfn = round_down(phys_ram_base, VMEMMAP_ADDR_ALIGN) >> PAGE_SHIFT;
+#endif
 	kernel_map.phys_addr = (uintptr_t)CONFIG_PHYS_RAM_BASE;
 	kernel_map.size = (uintptr_t)(&_end) - (uintptr_t)(&_start);