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authorSascha Hauer <s.hauer@pengutronix.de>2013-04-17 11:13:55 +0200
committerSascha Hauer <s.hauer@pengutronix.de>2013-04-17 13:37:14 +0200
commit67c6eeda9e5dea544cdeddb666f141c8467ab8d4 (patch)
tree922204f7ce006e731fb8eff27a69f460749b3e89 /commands/mm.c
parente10c1845b2351099c2097fe29629983002b63a37 (diff)
downloadbarebox-67c6eeda9e5dea544cdeddb666f141c8467ab8d4.tar.gz
Add memory modify command (mm)
As of now we have no way to manipulate individual bits of registers on the command line. This introduces a memory modify command which allows this. It has the syntax: mm [OPTIONS] <adr> <val> <mask> With [OPTIONS] being the usual memory command options (-b, -w, -l, -d <file>). Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Diffstat (limited to 'commands/mm.c')
-rw-r--r--commands/mm.c117
1 files changed, 117 insertions, 0 deletions
diff --git a/commands/mm.c b/commands/mm.c
new file mode 100644
index 0000000..f51fd27
--- /dev/null
+++ b/commands/mm.c
@@ -0,0 +1,117 @@
+/*
+ * Copyright (c) 2013 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <common.h>
+#include <command.h>
+#include <init.h>
+#include <driver.h>
+#include <malloc.h>
+#include <errno.h>
+#include <fs.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <linux/stat.h>
+#include <xfuncs.h>
+
+static int do_mem_mm(int argc, char *argv[])
+{
+ int ret = 0;
+ int fd;
+ char *filename = "/dev/mem";
+ int mode = O_RWSIZE_4;
+ loff_t adr;
+ int swab = 0;
+ u8 val8;
+ u16 val16;
+ u32 val32;
+ u32 value, mask;
+
+ if (mem_parse_options(argc, argv, "bwld:", &mode, NULL, &filename,
+ &swab) < 0)
+ return 1;
+
+ if (optind + 2 >= argc)
+ return COMMAND_ERROR_USAGE;
+
+ adr = strtoull_suffix(argv[optind++], NULL, 0);
+ value = simple_strtoul(argv[optind++], NULL, 0);
+ mask = simple_strtoul(argv[optind++], NULL, 0);
+
+ fd = open_and_lseek(filename, mode | O_RDWR, adr);
+ if (fd < 0)
+ return 1;
+
+ switch (mode) {
+ case O_RWSIZE_1:
+ ret = pread(fd, &val8, 1, adr);
+ if (ret < 0)
+ goto out_read;
+ val8 &= ~mask;
+ val8 |= (value & mask);
+ ret = pwrite(fd, &val8, 1, adr);
+ if (ret < 0)
+ goto out_write;
+ break;
+ case O_RWSIZE_2:
+ ret = pread(fd, &val16, 2, adr);
+ if (ret < 0)
+ goto out_read;
+ val16 &= ~mask;
+ val16 |= (value & mask);
+ ret = pwrite(fd, &val16, 2, adr);
+ if (ret < 0)
+ goto out_write;
+ break;
+ case O_RWSIZE_4:
+ if (ret < 0)
+ goto out_read;
+ ret = pread(fd, &val32, 4, adr);
+ val32 &= ~mask;
+ val32 |= (value & mask);
+ ret = pwrite(fd, &val32, 4, adr);
+ if (ret < 0)
+ goto out_write;
+ break;
+ }
+
+ close(fd);
+
+ return 0;
+
+out_read:
+ perror("read");
+ close(fd);
+ return 1;
+
+out_write:
+ perror("write");
+ close(fd);
+ return 1;
+}
+
+static const __maybe_unused char cmd_mm_help[] =
+"Usage: mm [OPTIONS] <adr> <val> <mask>\n"
+"set/clear bits specified with <mask> in <adr> to <value>\n"
+"options:\n"
+" -b, -w, -l use byte, halfword, or word accesses\n"
+" -d <file> write file (default /dev/mem)\n";
+
+BAREBOX_CMD_START(mm)
+ .cmd = do_mem_mm,
+ .usage = "memory modify write with mask",
+ BAREBOX_CMD_HELP(cmd_mm_help)
+BAREBOX_CMD_END