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Diffstat (limited to 'include/arch/aarch64/console_macros.S')
| -rw-r--r-- | include/arch/aarch64/console_macros.S | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/include/arch/aarch64/console_macros.S b/include/arch/aarch64/console_macros.S new file mode 100644 index 00000000..5c88d4f2 --- /dev/null +++ b/include/arch/aarch64/console_macros.S @@ -0,0 +1,88 @@ +/* + * Copyright (c) 2017-2018, ARM Limited and Contributors. All rights reserved. + * + * SPDX-License-Identifier: BSD-3-Clause + */ +#ifndef CONSOLE_MACROS_S +#define CONSOLE_MACROS_S + +#include <console.h> + +/* + * This macro encapsulates the common setup that has to be done at the end of + * a console driver's register function. It will register all of the driver's + * callbacks in the console_t structure and initialize the flags field (by + * default consoles are enabled for the "boot" and "crash" states, this can be + * changed after registration with the console_set_scope() function). It ends + * with a tail call that will include return to the caller. + * REQUIRES console_t pointer in x0 and a valid return address in x30. + */ +/* + * The USE_FINISH_CONSOLE_REG_2 guard is introduced to allow selection between + * the 2 variants of the finish_console_register macro and will be removed + * once the deprecated variant is removed. + */ +#ifndef USE_FINISH_CONSOLE_REG_2 +#if !ERROR_DEPRECATED + /* This version of the macro is deprecated. Use the new version */ + .macro finish_console_register _driver + /* + * Add these weak definitions so we will automatically write a 0 if the + * function doesn't exist. I'd rather use .ifdef but that only works if + * the function was defined (not just declared .global) above this point + * in the file, which we can't guarantee. + */ + .weak console_\_driver\()_putc + .weak console_\_driver\()_getc + .weak console_\_driver\()_flush + + /* Don't use adrp on weak funcs! See GNU ld bugzilla issue 22589. */ + ldr x1, =console_\_driver\()_putc + str x1, [x0, #CONSOLE_T_PUTC] + ldr x1, =console_\_driver\()_getc + str x1, [x0, #CONSOLE_T_GETC] + ldr x1, =console_\_driver\()_flush + str x1, [x0, #CONSOLE_T_FLUSH] + mov x1, #(CONSOLE_FLAG_BOOT | CONSOLE_FLAG_CRASH) + str x1, [x0, #CONSOLE_T_FLAGS] + b console_register + .endm +#endif /* ERROR_DEPRECATED */ +#else /* USE_FINISH_CONSOLE_REG_2 */ + /* The new version of the macro not using weak references */ + .macro finish_console_register _driver, putc=0, getc=0, flush=0 + /* + * If any of the callback is not specified or set as 0, then the + * corresponding callback entry in console_t is set to 0. + */ + .ifne \putc + adrp x1, console_\_driver\()_putc + add x1, x1, :lo12:console_\_driver\()_putc + str x1, [x0, #CONSOLE_T_PUTC] + .else + str xzr, [x0, #CONSOLE_T_PUTC] + .endif + + .ifne \getc + adrp x1, console_\_driver\()_getc + add x1, x1, :lo12:console_\_driver\()_getc + str x1, [x0, #CONSOLE_T_GETC] + .else + str xzr, [x0, #CONSOLE_T_GETC] + .endif + + .ifne \flush + adrp x1, console_\_driver\()_flush + add x1, x1, :lo12:console_\_driver\()_flush + str x1, [x0, #CONSOLE_T_FLUSH] + .else + str xzr, [x0, #CONSOLE_T_FLUSH] + .endif + + mov x1, #(CONSOLE_FLAG_BOOT | CONSOLE_FLAG_CRASH) + str x1, [x0, #CONSOLE_T_FLAGS] + b console_register + .endm +#endif /* USE_FINISH_CONSOLE_REG_2 */ + +#endif /* CONSOLE_MACROS_S */ |