On Sat, Nov 13, 2021 at 3:09 PM Amjad Ouled-Ameur aouledameur@baylibre.com wrote:

This will allow consumers to choose a pxe label at runtime instead of having to prompt the user. One good use-case for this, is choosing whether or not to apply a dtbo depending on the hardware configuration. e.g: for TI's AM335x EVM, it would be convenient to apply a particular dtbo only when the J9 jumper is on PRUSS mode. To achieve this, the pxe menu should have 2 labels, one with the dtbo and the other without, then the "pxe_label_override" env variable should point to the label with the dtbo at runtime only when the jumper is on PRUSS mode.

This change can be used for different use-cases and bring more flexibilty to consumers who use sysboot/pxe_utils.

if "pxe_label_override" is set but does not exist in the pxe menu, the code should fallback to the default label if given, and no failure is returned but rather a warning message.

Signed-off-by: Amjad Ouled-Ameur aouledameur@baylibre.com

Changes in v2:

• Use !strcmp() instead of strcmp()==0
• Add "pxe_label_override" documentation

boot/pxe_utils.c | 15 +++++++++++++++ doc/README.pxe | 6 ++++++ 2 files changed, 21 insertions(+)

diff --git a/boot/pxe_utils.c b/boot/pxe_utils.c index a7a84f26c1d5..defc806fdc4f 100644 --- a/boot/pxe_utils.c +++ b/boot/pxe_utils.c @@ -1349,9 +1349,11 @@ static struct menu *pxe_menu_to_menu(struct pxe_menu *cfg) struct pxe_label *label; struct list_head *pos; struct menu *m;

•   char *label_override;
    int err;
    int i = 1;
    char *default_num = NULL;
  

•   char *override_num = NULL;
  
    /*
     * Create a menu and add items for all the labels.
  

@@ -1361,6 +1363,8 @@ static struct menu *pxe_menu_to_menu(struct pxe_menu *cfg) if (!m) return NULL;

•   label_override = env_get("pxe_label_override");
  

•   list_for_each(pos, &cfg->labels) {
            label = list_entry(pos, struct pxe_label, list);
  
  

@@ -1372,6 +1376,17 @@ static struct menu *pxe_menu_to_menu(struct pxe_menu *cfg) if (cfg->default_label && (strcmp(label->name, cfg->default_label) == 0)) default_num = label->num;

•           if (label_override && !strcmp(label->name, label_override))
  

•                   override_num = label->num;
  

•   }
  

•   if (label_override) {
  

•           if (override_num)
  

•                   default_num = override_num;
  

•           else
  

•                   printf("Missing override pxe label: %s\n",
  

•                         label_override);
    }
  
    /*
  

diff --git a/doc/README.pxe b/doc/README.pxe index b67151ca510e..a1f0423adbec 100644 --- a/doc/README.pxe +++ b/doc/README.pxe @@ -92,6 +92,12 @@ pxe boot fdtoverlay_addr_r - location in RAM at which 'pxe boot' will temporarily store fdt overlay(s) before applying them to the fdt blob stored at 'fdt_addr_r'.

• pxe_label_override - override label to be used, if exists, instead of the
  

• default label. This will allow consumers to choose a pxe label at
  

• runtime instead of having to prompt the user. If "pxe_label_override" is set
  

• but does not exist in the pxe menu, pxe would fallback to the default label if
  

• given, and no failure is returned but rather a warning message.
  

pxe file format

The pxe file format is nearly a subset of the PXELINUX file format; see

2.25.1

Reviewed-by: Ramon Fried rfried.dev@gmail.com