[U-Boot] [PATCH] cmd: mem: Add a command to fill the memory with random data
Jean-Jacques Hiblot
jjhiblot at ti.com
Fri Jun 14 15:32:03 UTC 2019
This command fills the memory with data produced by rand().
Signed-off-by: Jean-Jacques Hiblot <jjhiblot at ti.com>
---
cmd/Kconfig | 3 ++-
cmd/mem.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 50 insertions(+), 1 deletion(-)
diff --git a/cmd/Kconfig b/cmd/Kconfig
index ea1a325eb3..ff96ac5d14 100644
--- a/cmd/Kconfig
+++ b/cmd/Kconfig
@@ -517,7 +517,7 @@ config CMD_MEMINFO
Display memory information.
config CMD_MEMORY
- bool "md, mm, nm, mw, cp, cmp, base, loop"
+ bool "md, mm, nm, mw, cp, cmp, base, loop, random"
default y
help
Memory commands.
@@ -529,6 +529,7 @@ config CMD_MEMORY
cmp - memory compare
base - print or set address offset
loop - initialize loop on address range
+ random - fill memory with random data
config CMD_MEMTEST
bool "memtest"
diff --git a/cmd/mem.c b/cmd/mem.c
index 392ed1756b..54e65be347 100644
--- a/cmd/mem.c
+++ b/cmd/mem.c
@@ -1082,6 +1082,47 @@ static int do_mem_crc(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
#endif
+int do_random(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+ unsigned long addr, len;
+ unsigned long seed; // NOT INITIALIZED ON PURPOSE
+ unsigned int *buf, *start;
+ unsigned char *buf8;
+ unsigned int i;
+
+ if (argc < 3 || argc > 4) {
+ printf("usage: %s <addr> <len> [<seed>]\n", argv[0]);
+ return 0;
+ }
+
+ len = simple_strtoul(argv[2], NULL, 16);
+ addr = simple_strtoul(argv[1], NULL, 16);
+
+ if (argc == 4) {
+ seed = simple_strtoul(argv[3], NULL, 16);
+ if (seed == 0) {
+ printf("The seed cannot be 0. Using 0xDEADBEEF.\n");
+ seed = 0xDEADBEEF;
+ }
+ } else {
+ seed = get_timer(0) ^ rand();
+ }
+
+ srand(seed);
+ start = map_sysmem(addr, len);
+ buf = start;
+ for (i = 0; i < (len / 4); i++)
+ *buf++ = rand();
+
+ buf8 = (unsigned char *)buf;
+ for (i = 0; i < (len % 4); i++)
+ *buf8++ = rand() & 0xFF;
+
+ unmap_sysmem(start);
+ printf("%lu bytes filled with random data\n", len);
+ return 1;
+}
+
/**************************************************/
U_BOOT_CMD(
md, 3, 1, do_mem_md,
@@ -1250,3 +1291,10 @@ U_BOOT_CMD(
""
);
#endif
+
+U_BOOT_CMD(
+ random, 4, 0, do_random,
+ "fill memory with random pattern",
+ "<addr> <len> [<seed>]\n"
+ " - Fill 'len' bytes of memory starting at 'addr' with random data\n"
+);
--
2.17.1
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