相关代码路径:

cmd/mem.c

配置:

make ARCH=arm CROSS_COMPILE=aarch64-linux-gnu- menuconfig

  CC      cmd/mem.o
cmd/mem.c: In function 'do_mem_mtest':
cmd/mem.c:883:10: error: 'CONFIG_SYS_MEMTEST_START' undeclared (first use in this function); did you mean 'CONFIG_SYS_MEMTEST_SCRATCH'?
  start = CONFIG_SYS_MEMTEST_START;
          ^~~~~~~~~~~~~~~~~~~~~~~~
          CONFIG_SYS_MEMTEST_SCRATCH
cmd/mem.c:883:10: note: each undeclared identifier is reported only once for each function it appears in
cmd/mem.c:884:8: error: 'CONFIG_SYS_MEMTEST_END' undeclared (first use in this function); did you mean 'CONFIG_SYS_MEMTEST_START'?
  end = CONFIG_SYS_MEMTEST_END;
        ^~~~~~~~~~~~~~~~~~~~~~
        CONFIG_SYS_MEMTEST_START
scripts/Makefile.build:278: recipe for target 'cmd/mem.o' failed
make[1]: *** [cmd/mem.o] Error 1
Makefile:1738: recipe for target 'cmd' failed
make: *** [cmd] Error 2

mem.c增加:

#define CONFIG_SYS_MEMTEST_START  (CONFIG_SYS_SDRAM_BASE )    // 
#define CONFIG_SYS_MEMTEST_END   (CONFIG_SYS_SDRAM_BASE + 1024*1024*512)  // 512M  

测试使用

# mtest help
mtest - simple RAM read/write test

Usage:
mtest [start [end [pattern [iterations]]]]

通过查看bdinfo ddr地址

# mtest  0x0000000040000100  0x0000000050000000 0x01   
Testing 40000100 ... 50000000: