target/linux/ramips/patches-5.4/0010-MIPS-add-bootargs-override-property.patch

   1 From f15d27f9c90ede4b16eb37f9ae573ef81c2b6996 Mon Sep 17 00:00:00 2001
   2 From: David Bauer <mail@david-bauer.net>
   3 Date: Thu, 31 Dec 2020 18:49:12 +0100
   4 Subject: [PATCH] MIPS: add bootargs-override property
   5
   6 Add support for the bootargs-override property to the chosen node
   7 similar to the one used on ipq806x or mpc85xx.
   8
   9 This is necessary, as the U-Boot used on some boards, notably the
  10 Ubiquiti UniFi 6 Lite, overwrite the bootargs property of the chosen
  11 node leading to a kernel panic when loading OpenWrt.
  12
  13 Signed-off-by: David Bauer <mail@david-bauer.net>
  14 ---
  15  arch/mips/kernel/setup.c | 30 ++++++++++++++++++++++++++++++
  16  1 file changed, 30 insertions(+)
  17
  18 --- a/arch/mips/kernel/setup.c
  19 +++ b/arch/mips/kernel/setup.c
  20 @@ -571,8 +571,28 @@ static int __init bootcmdline_scan_chose
  21         return 1;
  22  }
  23
  24 +static int __init bootcmdline_scan_chosen_override(unsigned long node, const char *uname,
  25 +                                                  int depth, void *data)
  26 +{
  27 +       bool *dt_bootargs = data;
  28 +       const char *p;
  29 +       int l;
  30 +
  31 +       if (depth != 1 || !data || strcmp(uname, "chosen") != 0)
  32 +               return 0;
  33 +
  34 +       p = of_get_flat_dt_prop(node, "bootargs-override", &l);
  35 +       if (p != NULL && l > 0) {
  36 +               strlcpy(boot_command_line, p, COMMAND_LINE_SIZE);
  37 +               *dt_bootargs = true;
  38 +       }
  39 +
  40 +       return 1;
  41 +}
  42 +
  43  static void __init bootcmdline_init(char **cmdline_p)
  44  {
  45 +       bool dt_bootargs_override = false;
  46         bool dt_bootargs = false;
  47
  48         /*
  49 @@ -586,6 +606,14 @@ static void __init bootcmdline_init(char
  50         }
  51
  52         /*
  53 +        * If bootargs-override in the chosen node is set, use this as the
  54 +        * command line
  55 +        */
  56 +       of_scan_flat_dt(bootcmdline_scan_chosen_override, &dt_bootargs_override);
  57 +       if (dt_bootargs_override)
  58 +               return;
  59 +
  60 +       /*
  61          * If the user specified a built-in command line &
  62          * MIPS_CMDLINE_BUILTIN_EXTEND, then the built-in command line is
  63          * prepended to arguments from the bootloader or DT so we'll copy them