[openwrt/openwrt] ipq806x: import bootargs-append from IPQ40xx

[LEDE Commits]

blogic pushed a commit to openwrt/openwrt.git, branch master:
https://git.openwrt.org/43a53891ce8f141e11960bc7b4ad369588ac341d

commit 43a53891ce8f141e11960bc7b4ad369588ac341d
Author: Robert Marko <robert.marko at sartura.hr>
AuthorDate: Mon May 18 12:35:15 2020 +0200

    ipq806x: import bootargs-append from IPQ40xx
    
    This imports the patch that adds bootargs-append support from IPQ40xx.
    
    This way we can append additional boot arguments from DTS instead of only being able to overwrite them.
    
    This way dual firmware devices can use the rootfs number that bootloader passes to decide from what to boot.
    But we still need to append console info and ubi root info.
    
    This is used by Edgecore ECW5410.
    
    Signed-off-by: Robert Marko <robert.marko at sartura.hr>
---
 .../ipq806x/patches-5.4/997-device_tree_cmdline.patch      | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/target/linux/ipq806x/patches-5.4/997-device_tree_cmdline.patch b/target/linux/ipq806x/patches-5.4/997-device_tree_cmdline.patch
new file mode 100644
index 0000000000..92f82b3788
--- /dev/null
+++ b/target/linux/ipq806x/patches-5.4/997-device_tree_cmdline.patch
@@ -0,0 +1,14 @@
+Index: linux-5.4.65/drivers/of/fdt.c
+===================================================================
+--- linux-5.4.65.orig/drivers/of/fdt.c
++++ linux-5.4.65/drivers/of/fdt.c
+@@ -1059,6 +1059,9 @@ int __init early_init_dt_scan_chosen(uns
+ 	p = of_get_flat_dt_prop(node, "bootargs", &l);
+ 	if (p != NULL && l > 0)
+ 		strlcpy(data, p, min(l, COMMAND_LINE_SIZE));
++	p = of_get_flat_dt_prop(node, "bootargs-append", &l);
++	if (p != NULL && l > 0)
++		strlcat(data, p, min_t(int, strlen(data) + (int)l, COMMAND_LINE_SIZE));
+ 
+ 	/*
+ 	 * CONFIG_CMDLINE is meant to be a default in case nothing else