AArch32: Add console driver
This patch adds console drivers including the pl011 driver
for the AArch32 mode.
Change-Id: Ifd22520d370fca3e73dbbf6f2d97d6aee65b67dd
diff --git a/drivers/console/aarch32/console.S b/drivers/console/aarch32/console.S
new file mode 100644
index 0000000..2993345
--- /dev/null
+++ b/drivers/console/aarch32/console.S
@@ -0,0 +1,114 @@
+/*
+ * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of ARM nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without specific
+ * prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+#include <asm_macros.S>
+
+ .globl console_init
+ .globl console_uninit
+ .globl console_putc
+ .globl console_getc
+
+ /*
+ * The console base is in the data section and not in .bss
+ * even though it is zero-init. In particular, this allows
+ * the console functions to start using this variable before
+ * the runtime memory is initialized for images which do not
+ * need to copy the .data section from ROM to RAM.
+ */
+.section .data.console_base ; .align 2
+ console_base: .word 0x0
+
+ /* -----------------------------------------------
+ * int console_init(uintptr_t base_addr,
+ * unsigned int uart_clk, unsigned int baud_rate)
+ * Function to initialize the console without a
+ * C Runtime to print debug information. It saves
+ * the console base to the data section.
+ * In: r0 - console base address
+ * r1 - Uart clock in Hz
+ * r2 - Baud rate
+ * out: return 1 on success else 0 on error
+ * Clobber list : r1 - r3
+ * -----------------------------------------------
+ */
+func console_init
+ /* Check the input base address */
+ cmp r0, #0
+ beq init_fail
+ ldr r3, =console_base
+ str r0, [r3]
+ b console_core_init
+init_fail:
+ bx lr
+endfunc console_init
+
+ /* -----------------------------------------------
+ * void console_uninit(void)
+ * Function to finish the use of console driver.
+ * It sets the console_base as NULL so that any
+ * further invocation of `console_putc` or
+ * `console_getc` APIs would return error.
+ * -----------------------------------------------
+ */
+func console_uninit
+ mov r0, #0
+ ldr r3, =console_base
+ str r0, [r3]
+ bx lr
+endfunc console_uninit
+
+ /* ---------------------------------------------
+ * int console_putc(int c)
+ * Function to output a character over the
+ * console. It returns the character printed on
+ * success or -1 on error.
+ * In : r0 - character to be printed
+ * Out : return -1 on error else return character.
+ * Clobber list : r1, r2
+ * ---------------------------------------------
+ */
+func console_putc
+ ldr r2, =console_base
+ ldr r1, [r2]
+ b console_core_putc
+endfunc console_putc
+
+ /* ---------------------------------------------
+ * int console_getc(void)
+ * Function to get a character from the console.
+ * It returns the character grabbed on success
+ * or -1 on error.
+ * Clobber list : r0, r1
+ * ---------------------------------------------
+ */
+func console_getc
+ ldr r1, =console_base
+ ldr r0, [r1]
+ b console_core_getc
+endfunc console_getc
diff --git a/drivers/console/aarch32/skeleton_console.S b/drivers/console/aarch32/skeleton_console.S
new file mode 100644
index 0000000..383874e
--- /dev/null
+++ b/drivers/console/aarch32/skeleton_console.S
@@ -0,0 +1,111 @@
+/*
+ * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of ARM nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without specific
+ * prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+#include <asm_macros.S>
+
+ /*
+ * This file contains a skeleton console implementation that can
+ * be used as basis for a real console implementation by platforms
+ * that do not contain PL011 hardware.
+ */
+
+ .globl console_core_init
+ .globl console_core_putc
+ .globl console_core_getc
+
+ /* -----------------------------------------------
+ * int console_core_init(uintptr_t base_addr,
+ * unsigned int uart_clk, unsigned int baud_rate)
+ * Function to initialize the console without a
+ * C Runtime to print debug information. This
+ * function will be accessed by console_init and
+ * crash reporting.
+ * In: r0 - console base address
+ * r1 - Uart clock in Hz
+ * r2 - Baud rate
+ * Out: return 1 on success else 0 on error
+ * Clobber list : r1, r2
+ * -----------------------------------------------
+ */
+func console_core_init
+ /* Check the input base address */
+ cmp r0, #0
+ beq core_init_fail
+ /* Check baud rate and uart clock for sanity */
+ cmp r1, #0
+ beq core_init_fail
+ cmp r2, #0
+ beq core_init_fail
+ /* Insert implementation here */
+ mov r0, #1
+ bx lr
+core_init_fail:
+ mov r0, #0
+ bx lr
+endfunc console_core_init
+
+ /* --------------------------------------------------------
+ * int console_core_putc(int c, uintptr_t base_addr)
+ * Function to output a character over the console. It
+ * returns the character printed on success or -1 on error.
+ * In : r0 - character to be printed
+ * r1 - console base address
+ * Out : return -1 on error else return character.
+ * Clobber list : r2
+ * --------------------------------------------------------
+ */
+func console_core_putc
+ /* Check the input parameter */
+ cmp r1, #0
+ beq putc_error
+ /* Insert implementation here */
+ bx lr
+putc_error:
+ mov r0, #-1
+ bx lr
+endfunc console_core_putc
+
+ /* ---------------------------------------------
+ * int console_core_getc(uintptr_t base_addr)
+ * Function to get a character from the console.
+ * It returns the character grabbed on success
+ * or -1 on error.
+ * In : r0 - console base address
+ * Clobber list : r0, r1
+ * ---------------------------------------------
+ */
+func console_core_getc
+ cmp r0, #0
+ beq getc_error
+ /* Insert implementation here */
+ bx lr
+getc_error:
+ mov r0, #-1
+ bx lr
+endfunc console_core_getc