Adding upstream version 2.8.0+dfsg.upstream/2.8.0+dfsgupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 170 insertions, 0 deletions

diff --git a/drivers/console/aarch64/skeleton_console.S b/drivers/console/aarch64/skeleton_console.S
new file mode 100644
index 0000000..7ea2eec
--- /dev/null
+++ b/drivers/console/aarch64/skeleton_console.S
@@ -0,0 +1,170 @@
+/*
+ * Copyright (c) 2015-2020, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+#include <asm_macros.S>
+#include <console_macros.S>
+
+	/*
+	 * This file contains a skeleton console driver that can be used as a
+	 * basis for a real console driver. Console drivers in Trusted Firmware
+	 * can be instantiated multiple times. Each instance is described by a
+	 * separate console_t structure which must be registered with the common
+	 * console framework via console_register(). Console drivers should
+	 * define a console_xxx_register() function that initializes a new
+	 * console_t structure passed in from the caller and registers it after
+	 * initializing the console hardware. Drivers may define their own
+	 * structures extending console_t to store private driver information.
+	 * Console drivers *MUST* ensure that the console callbacks they
+	 * implement only change registers allowed in the clobber lists defined
+	 * in this file. (Note that in addition to the explicit clobber lists,
+	 * any function may always clobber the intra-procedure-call registers
+	 * X16 and X17, but may never depend on them retaining their values
+	 * across any function call.)
+	 */
+
+	.globl	console_xxx_register
+	.globl	console_xxx_putc
+	.globl	console_xxx_getc
+	.globl	console_xxx_flush
+
+	/* -----------------------------------------------
+	 * int console_xxx_register(console_xxx_t *console,
+	 * 	...additional parameters as desired...)
+	 * Function to initialize and register the console.
+	 * The caller needs to pass an empty console_xxx_t
+	 * structure in which *MUST* be allocated in
+	 * persistent memory (e.g. a global or static local
+	 * variable, *NOT* on the stack).
+	 * In : x0 - pointer to empty console_t structure
+	 *      x1 through x7: additional parameters as desired
+	 * Out: x0 - 1 on success, 0 on error
+	 * Clobber list : x0 - x7
+	 * -----------------------------------------------
+	 */
+func console_xxx_register
+	/*
+	 * Store parameters (e.g. hardware base address) in driver-specific
+	 * console_xxx_t structure field if they will need to be retrieved
+	 * by later console callback (e.g. putc).
+	 * Example:
+	 */
+	str	x1, [x0, #CONSOLE_T_BASE]
+	str	x2, [x0, #CONSOLE_T_XXX_SOME_OTHER_VALUE]
+
+	/*
+	 * Initialize console hardware, using x1 - x7 parameters as needed.
+	 * Keep console_t pointer in x0 for later.
+	 */
+
+	/*
+	 * Macro to finish up registration and return (needs valid x0 + x30).
+	 * If any of the argument is unspecified, then the corresponding
+	 * entry in console_t is set to 0.
+	 */
+	finish_console_register xxx putc=1, getc=1, flush=1
+
+	/* Jump here if hardware init fails or parameters are invalid. */
+register_fail:
+	mov	w0, #0
+	ret
+endfunc console_xxx_register
+
+	/* --------------------------------------------------------
+	 * int console_xxx_putc(int c, console_xxx_t *console)
+	 * Function to output a character over the console. It
+	 * returns the character printed on success or -1 on error.
+	 * In : w0 - character to be printed
+	 *      x1 - pointer to console_t struct
+	 * Out: w0 - printed character on success, < 0 on error.
+	 * Clobber list : x0, x1, x2
+	 * --------------------------------------------------------
+	 */
+func console_xxx_putc
+	/*
+	 * Retrieve values we need (e.g. hardware base address) from
+	 * console_xxx_t structure pointed to by x1.
+	 * Example:
+	 */
+	ldr	x1, [x1, #CONSOLE_T_BASE]
+
+	/*
+	 * Write w0 to hardware.
+	 */
+
+	ret
+
+	/* Jump here if output fails for any reason. */
+putc_error:
+	mov	w0, #-1
+	ret
+endfunc console_xxx_putc
+
+	/* ---------------------------------------------
+	 * int console_xxx_getc(console_xxx_t *console)
+	 * Function to get a character from the console.
+	 * Even though console_getc() is blocking, this
+	 * callback has to be non-blocking and always
+	 * return immediately to allow polling multiple
+	 * drivers concurrently.
+	 * Returns the character grabbed on success,
+	 * ERROR_NO_PENDING_CHAR if no character was
+	 * available at this time, or any value
+	 * between -2 and -127 if there was an error.
+	 * In : x0 - pointer to console_t struct
+	 * Out: w0 - character on success,
+	 *           ERROR_NO_PENDING_CHAR if no char,
+	 *           < -1 on error
+	 * Clobber list : x0, x1
+	 * ---------------------------------------------
+	 */
+func console_xxx_getc
+	/*
+	 * Retrieve values we need (e.g. hardware base address) from
+	 * console_xxx_t structure pointed to by x0.
+	 * Example:
+	 */
+	ldr	x1, [x0, #CONSOLE_T_BASE]
+
+	/*
+	 * Try to read character into w0 from hardware.
+	 */
+
+	ret
+
+	/* Jump here if there is no character available at this time. */
+getc_no_char:
+	mov	w0, #ERROR_NO_PENDING_CHAR
+	ret
+
+	/* Jump here if there was any hardware error. */
+getc_error:
+	mov	w0, #-2		/* may pick error codes between -2 and -127 */
+	ret
+endfunc console_xxx_getc
+
+	/* ---------------------------------------------
+	 * void console_xxx_flush(console_xxx_t *console)
+	 * Function to force a write of all buffered
+	 * data that hasn't been output.
+	 * In : x0 - pointer to console_xxx_t struct
+	 * Out: void
+	 * Clobber list : x0, x1, x2, x3, x4, x5
+	 * ---------------------------------------------
+	 */
+func console_xxx_flush
+	/*
+	 * Retrieve values we need (e.g. hardware base address) from
+	 * console_xxx_t structure pointed to by x0.
+	 * Example:
+	 */
+	ldr	x1, [x0, #CONSOLE_T_BASE]
+
+	/*
+	 * Flush all remaining output from hardware FIFOs. Do not return until
+	 * all data has been flushed or there was an unrecoverable error.
+	 */
+
+	ret
+endfunc console_xxx_flush