On 25.10.18 17:38, [ext] Andreas J. Reichel wrote:
From: Andreas Reichel <[email protected]>
Give the user a chance to override kernel arguments.
EBG waits for 3 seconds and checks if user pressed the <a> key.
This can help in unbricking a system.
We have no chance to make this runtime configurable?
Signed-off-by: Andreas Reichel <[email protected]>
---
configure.ac | 12 ++++++++++++
main.c | 29 ++++++++++++++++++++++++++++-
2 files changed, 40 insertions(+), 1 deletion(-)
diff --git a/configure.ac b/configure.ac
index 6c7f381..784defa 100644
--- a/configure.ac
+++ b/configure.ac
@@ -166,6 +166,16 @@ AC_ARG_WITH([mem-uservars],
AC_DEFINE_UNQUOTED([ENV_MEM_USERVARS], [${ENV_MEM_USERVARS}], [Reserved memory for user variables])
+AC_ARG_ENABLE([boot-keys],
+ AS_HELP_STRING([--enable-boot-keys], [enable on-boot hot keys for
debugging]),
+ [
+ EBG_BOOT_KEYS=[enabled]
+ AC_DEFINE([EBG_BOOT_KEYS],[1],[Enable on-boot hot keys])
+ ],
+ [
+ EBG_BOOT_KEYS=[disabled]
+ ])
+
dnl pkg-config
AC_PATH_PROG(PKG_CONFIG, pkg-config, no)
if test "x$PKG_CONFIG" = "xno"; then
@@ -196,4 +206,6 @@ AC_MSG_RESULT([
environment backend: ${ENV_API_FILE}.c
number of config parts: ${ENV_NUM_CONFIG_PARTS}
reserved for uservars: ${ENV_MEM_USERVARS} bytes
+
+ ebg boot keys: ${EBG_BOOT_KEYS}
])
diff --git a/main.c b/main.c
index 9fe8bbe..410da4e 100644
--- a/main.c
+++ b/main.c
@@ -22,6 +22,8 @@
#include <configuration.h>
#include "version.h"
#include "utils.h"
+#include "config.h"
+#include "envdata.h"
extern const unsigned long init_array_start[];
extern const unsigned long init_array_end[];
@@ -198,11 +200,36 @@ EFI_STATUS efi_main(EFI_HANDLE image_handle,
EFI_SYSTEM_TABLE *system_table)
status);
}
+#ifdef EBG_BOOT_KEYS
+ EFI_INPUT_KEY key;
+ CHAR16 input_buffer[ENV_STRING_LENGTH];
+
+ /* Give user a chance to change the boot parameters on the fly */
+ Color(system_table, 15, 0);
+ Print(L"Press <a> to change kernel arguments\n");
+ Color(system_table, 7, 0);
+
+ /* Wait for key for 3 seconds */
+ WaitForSingleEvent(system_table->ConIn->WaitForKey, 30000000);
This value might be worth to be configurable as well. "0" could mean "do not
wait".
+
+ input_buffer[0] = L'\0';
+ if (uefi_call_wrapper(system_table->ConIn->ReadKeyStroke,
+ 2, system_table->ConIn, &key) == EFI_SUCCESS) {
+ if (key.UnicodeChar == L'a') {
+ Input(L"\nInput kernel args (empty str to cancel): ",
+ input_buffer, ENV_STRING_LENGTH - 1);
+ }
+ }
+ if (StrLen(input_buffer) > 0) {
+ StrCpy(bg_loader_params.payload_options, input_buffer);
+ }
+#endif //EBG_BOOT_KEYS
+
loaded_image->LoadOptions = bg_loader_params.payload_options;
loaded_image->LoadOptionsSize =
(StrLen(bg_loader_params.payload_options) + 1) * sizeof(CHAR16);
- Print(L"Starting %s with watchdog set to %d seconds\n",
+ Print(L"\nStarting %s with watchdog set to %d seconds\n",
The line break should go into the conditional path.
bg_loader_params.payload_path, bg_loader_params.timeout);
return uefi_call_wrapper(BS->StartImage, 3, payload_handle, 0, 0);
Jan
--
Siemens AG, Corporate Technology, CT RDA IOT SES-DE
Corporate Competence Center Embedded Linux
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