of: Support CONFIG_CMDLINE_EXTEND config option
The old logic assumes CMDLINE_FROM_BOOTLOADER vs. CMDLINE_FORCE and
ignores CMDLINE_EXTEND. Here's the old logic:
- CONFIG_CMDLINE_FORCE=true
CONFIG_CMDLINE
- dt bootargs=non-empty:
dt bootargs
- dt bootargs=empty, @data is non-empty string
@data is left unchanged
- dt bootargs=empty, @data is empty string
CONFIG_CMDLINE (or "" if that's not defined)
The new logic is now documented in of_fdt.h and is copied here for
reference:
- CONFIG_CMDLINE_FORCE=true
CONFIG_CMDLINE
- CONFIG_CMDLINE_EXTEND=true, @data is non-empty string
@data + dt bootargs (even if dt bootargs are empty)
- CONFIG_CMDLINE_EXTEND=true, @data is empty string
CONFIG_CMDLINE + dt bootargs (even if dt bootargs are empty)
- CMDLINE_FROM_BOOTLOADER=true, dt bootargs=non-empty:
dt bootargs
- CMDLINE_FROM_BOOTLOADER=true, dt bootargs=empty, @data is non-empty string
@data is left unchanged
- CMDLINE_FROM_BOOTLOADER=true, dt bootargs=empty, @data is empty string
CONFIG_CMDLINE (or "" if that's not defined)
Signed-off-by: Doug Anderson <dianders@chromium.org>
CC: devicetree-discuss@lists.ozlabs.org
CC: Grant Likely <grant.likely@secretlab.ca>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Rob Herring <rob.herring@calxeda.com>
Change-Id: I40ace250847f813358125dfcaa8998fd32cf7ea3
Signed-off-by: Colin Cross <ccross@android.com>
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 55f1b83..98a73f6 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -1063,6 +1063,29 @@
return 0;
}
+/*
+ * Convert configs to something easy to use in C code
+ */
+#if defined(CONFIG_CMDLINE_FORCE)
+static const int overwrite_incoming_cmdline = 1;
+static const int read_dt_cmdline;
+static const int concat_cmdline;
+#elif defined(CONFIG_CMDLINE_EXTEND)
+static const int overwrite_incoming_cmdline;
+static const int read_dt_cmdline = 1;
+static const int concat_cmdline = 1;
+#else /* CMDLINE_FROM_BOOTLOADER */
+static const int overwrite_incoming_cmdline;
+static const int read_dt_cmdline = 1;
+static const int concat_cmdline;
+#endif
+
+#ifdef CONFIG_CMDLINE
+static const char *config_cmdline = CONFIG_CMDLINE;
+#else
+static const char *config_cmdline = "";
+#endif
+
int __init early_init_dt_scan_chosen(unsigned long node, const char *uname,
int depth, void *data)
{
@@ -1077,28 +1100,23 @@
early_init_dt_check_for_initrd(node);
- /* Retrieve command line */
- p = of_get_flat_dt_prop(node, "bootargs", &l);
- if (p != NULL && l > 0)
- strlcpy(data, p, min((int)l, COMMAND_LINE_SIZE));
+ /* Put CONFIG_CMDLINE in if forced or if data had nothing in it to start */
+ if (overwrite_incoming_cmdline || !((char *)data)[0])
+ strlcpy(data, config_cmdline, COMMAND_LINE_SIZE);
- /*
- * CONFIG_CMDLINE is meant to be a default in case nothing else
- * managed to set the command line, unless CONFIG_CMDLINE_FORCE
- * is set in which case we override whatever was found earlier.
- */
-#ifdef CONFIG_CMDLINE
-#if defined(CONFIG_CMDLINE_EXTEND)
- strlcat(data, " ", COMMAND_LINE_SIZE);
- strlcat(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
-#elif defined(CONFIG_CMDLINE_FORCE)
- strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
-#else
- /* No arguments from boot loader, use kernel's cmdl*/
- if (!((char *)data)[0])
- strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
-#endif
-#endif /* CONFIG_CMDLINE */
+ /* Retrieve command line unless forcing */
+ if (read_dt_cmdline) {
+ p = of_get_flat_dt_prop(node, "bootargs", &l);
+ if (p != NULL && l > 0) {
+ if (concat_cmdline) {
+ strlcat(data, " ", COMMAND_LINE_SIZE);
+ strlcat(data, p, min_t(int, (int)l,
+ COMMAND_LINE_SIZE));
+ } else
+ strlcpy(data, p, min_t(int, (int)l,
+ COMMAND_LINE_SIZE));
+ }
+ }
pr_debug("Command line is: %s\n", (char*)data);