diff -drupN a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c
--- a/arch/mips/kernel/setup.c	2017-10-21 18:09:07.000000000 +0300
+++ b/arch/mips/kernel/setup.c	2022-06-09 05:02:27.000000000 +0300
@@ -26,6 +26,7 @@
 #include <linux/sizes.h>
 #include <linux/device.h>
 #include <linux/dma-contiguous.h>
+#include <linux/of_fdt.h>
 
 #include <asm/addrspace.h>
 #include <asm/bootinfo.h>
@@ -625,6 +626,89 @@ static void __init request_crashkernel(s
 #define USE_DTB_CMDLINE		IS_ENABLED(CONFIG_MIPS_CMDLINE_FROM_DTB)
 #define EXTEND_WITH_PROM	IS_ENABLED(CONFIG_MIPS_CMDLINE_EXTEND)
 
+#ifdef CONFIG_LINUX_PMEM
+static unsigned long  g_pmem_total_size=0;
+static unsigned long  g_pmem_start=0;
+static int  g_pmem_set_by_cmdline=0;
+
+#if 0
+/* called in arch/mips/xburst2/soc-x2000-v12/setup.c */
+unsigned long set_reserved_pmem_total_size(unsigned long size)
+{
+	g_pmem_total_size = size;
+	return 0;
+}
+#endif
+
+unsigned long get_reserved_pmem_size(void)
+{
+	return g_pmem_total_size;
+}
+
+unsigned long get_reserved_pmem_start(void)
+{
+	return g_pmem_start;
+}
+
+static int __init pmem_parse(char *str)
+{
+	char *retptr;
+	unsigned long pmem_size;
+	unsigned long pmem_base = -1;
+
+	pmem_size = memparse(str, &retptr);
+	if(pmem_size < 0) {
+		printk("pmem_size is error!\n");
+		/* pmem_size = 0x4000000; */
+		goto abort;
+	}
+
+	if (*retptr == '@')
+		pmem_base = memparse(retptr + 1, NULL);
+
+	if(pmem_base < 0) {
+		printk("pmem_base is error!\n");
+		/* pmem_base = 0xc000000; */
+		goto abort;
+	}
+
+	g_pmem_start = pmem_base;
+	g_pmem_total_size = pmem_size;
+	g_pmem_set_by_cmdline = 1;
+
+	return 1;
+abort:
+	return 0;
+}
+__setup("pmem=", pmem_parse);
+
+static unsigned int str2(unsigned int *i, const char *str, int v)
+{
+	unsigned int temp = 0;
+
+	while(*str != 0) {
+		if((*str>='0') && (*str<='9') && (v == 10))
+			temp = temp*v + (*str - '0');
+		else if ((*str>='A') && (*str<='F') && (v == 16))
+			temp = temp*v + (*str - 'A') + 10;
+		else
+			break;
+		str++;
+	}
+
+	*i = temp;
+
+	if (v == 10) {
+		if (*str == 'M')
+			return 1024 * 1024;
+		else if (*str == 'K')
+			return 1024;
+	}
+
+	return 1;
+}
+#endif	/* CONFIG_LINUX_PMEM  */
+
 static void __init arch_mem_init(char **cmdline_p)
 {
 	struct memblock_region *reg;
@@ -678,6 +762,59 @@ static void __init arch_mem_init(char **
 		pr_info("User-defined physical RAM map:\n");
 		print_memory_map();
 	}
+#ifdef CONFIG_LINUX_PMEM
+	/* reserve memory for pmem. */
+	if (g_pmem_set_by_cmdline == 0) {
+		char *str = CONFIG_PMEM_RESERVE_SIZE;
+		unsigned int size;
+
+		do {
+			if (strlen(str) == 1) {
+				g_pmem_total_size = 0;
+				break;
+			} else if ((*(str+1) == 'x') || (*(str+1) == 'X')) {
+				str2(&size, str+2, 16);
+				g_pmem_total_size = size;
+				break;
+			} else {
+				unsigned int f = str2(&size, str, 10);
+				g_pmem_total_size = size * f;
+				break;
+			}
+		} while(0);
+	}
+
+	printk(KERN_INFO "reserve memory for pmem, g_pmem_total_size: %#x\n",  (unsigned int)g_pmem_total_size);
+	if ( g_pmem_total_size > 0x10000 ) {
+		int i;
+		const int field = 2 * sizeof(unsigned long);
+
+		for (i = boot_mem_map.nr_map-1; i>-1; i--) {
+
+			if (BOOT_MEM_RAM == boot_mem_map.map[i].type
+			    && (unsigned long)boot_mem_map.map[i].size > g_pmem_total_size) {
+
+				printk(KERN_INFO "          original, memory %d: %0*Lx @ %0*Lx \n", i,
+				       field, (unsigned long long) boot_mem_map.map[i].size,
+				       field, (unsigned long long) boot_mem_map.map[i].addr);
+
+				boot_mem_map.map[i].size -= g_pmem_total_size;
+				g_pmem_start = (unsigned long)boot_mem_map.map[i].addr + (unsigned long)boot_mem_map.map[i].size;
+
+				printk(KERN_INFO "after reserve pmem, memory %d: %0*Lx @ %0*Lx \n", i,
+				       field, (unsigned long long) boot_mem_map.map[i].size,
+				       field, (unsigned long long) boot_mem_map.map[i].addr);
+
+				printk(KERN_INFO "     reserve memory for pmem: %0*Lx @ %0*Lx ",
+				       field, (unsigned long long) g_pmem_total_size,
+				       field, (unsigned long long) g_pmem_start);
+				printk(KERN_INFO "\n");
+
+				break;
+			}
+		}
+	}
+#endif	/* CONFIG_LINUX_PMEM  */
 
 	bootmem_init();
 #ifdef CONFIG_PROC_VMCORE
@@ -701,6 +838,10 @@ static void __init arch_mem_init(char **
 	plat_swiotlb_setup();
 	paging_init();
 
+
+	early_init_fdt_reserve_self();
+	early_init_fdt_scan_reserved_mem();
+
 	dma_contiguous_reserve(PFN_PHYS(max_low_pfn));
 	/* Tell bootmem about cma reserved memblock section */
 	for_each_memblock(reserved, reg)