On 10/4/18 5:46 AM, Nick Kossifidis wrote:
The /chosen node is optional so we should handle CMDLINE regardless
the presence of /chosen/bootargs. Move handling of CMDLINE in
early_init_dt_scan() instead.
Signed-off-by: Nick Kossifidis <mick@xxxxxxxxxxxx>
---
drivers/of/fdt.c | 69 +++++++++++++++++++++++++++++++++++++++-----------------
1 file changed, 48 insertions(+), 21 deletions(-)
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 800ad252c..868464b0b 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -31,6 +31,14 @@
#include "of_private.h"
+#ifdef CONFIG_CMDLINE
+#ifdef CONFIG_CMDLINE_FORCE
+static const char fixed_cmdline[] __initconst = CONFIG_CMDLINE;
+#else
+static char builtin_cmdline[] __initdata = CONFIG_CMDLINE;
+#endif
+#endif
+
/*
* of_fdt_limit_memory - limit the number of regions in the /memory node
* @limit: maximum entries
@@ -1088,28 +1096,10 @@ int __init early_init_dt_scan_chosen(unsigned long node, const char *uname,
/* Retrieve command line */
p = of_get_flat_dt_prop(node, "bootargs", &l);
- if (p != NULL && l > 0)
+ if (p != NULL && l > 0) {
strlcpy(data, p, min((int)l, 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 */
-
- pr_debug("Command line is: %s\n", (char*)data);
+ pr_debug("Got bootargs: %s\n", (char *) data);
+ }
/* break now */
return 1;
@@ -1240,6 +1230,43 @@ bool __init early_init_dt_scan(void *params)
return false;
early_init_dt_scan_nodes();
+
+ /*
+ * The /chosen node normaly contains the bootargs element
/s/normaly/normally
+ * that includes the kernel's command line parameters.
+ * However the presence of /chosen is not mandatory so
+ * in case we didn't get a command line when scanning
+ * nodes above, we should provide one here before we
+ * return, if possible.
+ *
+ * The built-in command line can be used as a default
+ * command line in case we received nothing from the
+ * device tree/bootloader. It can also be used for
+ * extending or replacing the received command line.
+ */
+#ifdef CONFIG_CMDLINE
+#if defined(CONFIG_CMDLINE_EXTEND)
+ /*
+ * Order of parameters shouldn't matter for most cases,
+ * so prepending or appending the built-in command line
+ * shouldn't make a difference. In cases where it does
+ * it's up to the user to configure the kernel and/or
+ * the bootloader properly.
+ */
+ if (builtin_cmdline[0]) {
+ strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
+ strlcat(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE)
+ }
+#elif defined(CONFIG_CMDLINE_FORCE)
+ if (fixed_cmdline[0])
+ strlcpy(boot_command_line, fixed_cmdline, COMMAND_LINE_SIZE);
+#else
+ /* No arguments from boot loader, use kernel's cmdline */
+ if (!boot_command_line[0] && builtin_cmdline[0])
+ strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
+#endif
+#endif /* CONFIG_CMDLINE */
+
Any specific reason for doing this in early_init_dt_scan instead of
early_init_dt_scan_chosen?
I think keeping all boot command line modifications at one place makes
more sense.
Regards,
Atish
return true;
}
