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* [PATCH] arch: riscv: support kernel command line forcing when no DTB passed
@ 2018-12-18  3:15 ` Paul Walmsley
  0 siblings, 0 replies; 14+ messages in thread
From: Paul Walmsley @ 2018-12-18  3:15 UTC (permalink / raw)
  To: linux-riscv, linux-kernel; +Cc: palmer, aou, paul


CONFIG_CMDLINE_FORCE doesn't work on RISC-V when no DTB is passed into
the kernel.  This is because the code that forces the kernel command
line only runs if a valid DTB is present at boot.  During debugging,
it's useful to have the ability to force kernel command lines even
when no DTB is present.  This patch adds support for doing so.

Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: linux-riscv@lists.infradead.org
Cc: linux-kernel@vger.kernel.org (open list)
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
---

Applies on v4.20-rc7.

 arch/riscv/kernel/setup.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
index 2c290e6aaa6e..e6b962ff39b1 100644
--- a/arch/riscv/kernel/setup.c
+++ b/arch/riscv/kernel/setup.c
@@ -171,7 +171,14 @@ asmlinkage void __init setup_vm(void)
 
 void __init parse_dtb(unsigned int hartid, void *dtb)
 {
-	early_init_dt_scan(__va(dtb));
+	if (!early_init_dt_scan(__va(dtb)))
+		return;
+
+	pr_err("No DTB passed to the kernel\n");
+#ifdef CONFIG_CMDLINE_FORCE
+	strlcpy(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
+	pr_info("Forcing kernel command line to: %s\n", boot_command_line);
+#endif
 }
 
 static void __init setup_bootmem(void)
-- 
2.20.0


^ permalink raw reply related	[flat|nested] 14+ messages in thread

end of thread, other threads:[~2019-02-19 21:20 UTC | newest]

Thread overview: 14+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-12-18  3:15 [PATCH] arch: riscv: support kernel command line forcing when no DTB passed Paul Walmsley
2018-12-18  3:15 ` Paul Walmsley
2019-01-15 15:44 ` Christoph Hellwig
2019-01-15 15:44   ` Christoph Hellwig
2019-02-05 17:43 ` Andreas Schwab
2019-02-05 17:43   ` Andreas Schwab
2019-02-19 21:19   ` Paul Walmsley
2019-02-19 21:19     ` Paul Walmsley
2019-02-07 14:44 ` [PATCH] arch: riscv: fix logic error in parse_dtb Andreas Schwab
2019-02-07 14:44   ` Andreas Schwab
2019-02-07 22:47   ` Atish Patra
2019-02-07 22:47     ` Atish Patra
2019-02-19 21:20   ` Paul Walmsley
2019-02-19 21:20     ` Paul Walmsley

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