drivers/ti/uart/aarch64/16550_console.S - imx-atf - Git at Google

 /*
  * Copyright (c) 2015-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */

 #include <arch.h>
 #include <asm_macros.S>
 #include <assert_macros.S>
 #include <console_macros.S>
 #include <uart_16550.h>

 	/*
 	 * "core" functions are low-level implementations that don't require
 	 * writable memory and are thus safe to call in BL1 crash context.
 	 */
 	.globl console_16550_core_init
 	.globl console_16550_core_putc
 	.globl console_16550_core_getc
 	.globl console_16550_core_flush

 	.globl console_16550_putc
 	.globl console_16550_getc
 	.globl console_16550_flush

 	/* -----------------------------------------------
 	 * int console_16550_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: x0 - console base address
 	 *     w1 - Uart clock in Hz
 	 *     w2 - Baud rate
 	 * Out: return 1 on success, 0 on error
 	 * Clobber list : x1, x2, x3
 	 * -----------------------------------------------
 	 */
 func console_16550_core_init
 	/* Check the input base address */
 	cbz	x0, init_fail
 	/* Check baud rate and uart clock for sanity */
 	cbz	w1, init_fail
 	cbz	w2, init_fail

 	/* Program the baudrate */
 	/* Divisor =  Uart clock / (16 * baudrate) */
 	lsl	w2, w2, #4
 	udiv	w2, w1, w2
 	and	w1, w2, #0xff		/* w1 = DLL */
 	lsr	w2, w2, #8
 	and	w2, w2, #0xff		/* w2 = DLLM */
 	ldr	w3, [x0, #UARTLCR]
 	orr	w3, w3, #UARTLCR_DLAB
 	str	w3, [x0, #UARTLCR]	/* enable DLL, DLLM programming */
 	str	w1, [x0, #UARTDLL]	/* program DLL */
 	str	w2, [x0, #UARTDLLM]	/* program DLLM */
 	mov	w2, #~UARTLCR_DLAB
 	and	w3, w3, w2
 	str	w3, [x0, #UARTLCR]	/* disable DLL, DLLM programming */

 	/* 8n1 */
 	mov	w3, #3
 	str	w3, [x0, #UARTLCR]
 	/* no interrupt */
 	mov	w3, #0
 	str	w3, [x0, #UARTIER]
 #ifdef TI_16550_MDR_QUIRK
 	/* UART must be enabled on some platforms via the MDR register */
 	str	w3, [x0, #UARTMDR1]
 #endif /* TI_16550_MDR_QUIRK */
 	/* enable fifo, DMA */
 	mov	w3, #(UARTFCR_FIFOEN | UARTFCR_DMAEN)
 	str	w3, [x0, #UARTFCR]
 	/* DTR + RTS */
 	mov	w3, #3
 	str	w3, [x0, #UARTMCR]
 	mov	w0, #1
 	ret
 init_fail:
 	mov	w0, #0
 	ret
 endfunc console_16550_core_init

 #if MULTI_CONSOLE_API
 	.globl console_16550_register

 	/* -----------------------------------------------
 	 * int console_16550_register(console_16550_t *console,
 		uintptr_t base, uint32_t clk, uint32_t baud)
 	 * Function to initialize and register a new 16550
 	 * console. Storage passed in for the console struct
 	 * *must* be persistent (i.e. not from the stack).
 	 * In: x0 - UART register base address
 	 *     w1 - UART clock in Hz
 	 *     w2 - Baud rate
 	 *     x3 - pointer to empty console_16550_t struct
 	 * Out: return 1 on success, 0 on error
 	 * Clobber list : x0, x1, x2, x6, x7, x14
 	 * -----------------------------------------------
 	 */
 func console_16550_register
 	mov	x7, x30
 	mov	x6, x3
 	cbz	x6, register_fail
 	str	x0, [x6, #CONSOLE_T_16550_BASE]

 	bl	console_16550_core_init
 	cbz	x0, register_fail

 	mov	x0, x6
 	mov	x30, x7
 	finish_console_register 16550

 register_fail:
 	ret	x7
 endfunc console_16550_register
 #else
 	.globl console_core_init
 	.globl console_core_putc
 	.globl console_core_getc
 	.globl console_core_flush
 	.equ console_core_init,console_16550_core_init
 	.equ console_core_putc,console_16550_core_putc
 	.equ console_core_getc,console_16550_core_getc
 	.equ console_core_flush,console_16550_core_flush
 #endif

 	/* --------------------------------------------------------
 	 * int console_16550_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 : w0 - character to be printed
 	 *      x1 - console base address
 	 * Out : return -1 on error else return character.
 	 * Clobber list : x2
 	 * --------------------------------------------------------
 	 */
 func console_16550_core_putc
 #if ENABLE_ASSERTIONS
 	cmp	x1, #0
 	ASM_ASSERT(ne)
 #endif /* ENABLE_ASSERTIONS */

 	/* Prepend '\r' to '\n' */
 	cmp	w0, #0xA
 	b.ne	2f
 	/* Check if the transmit FIFO is full */
 1:	ldr	w2, [x1, #UARTLSR]
 	and	w2, w2, #(UARTLSR_TEMT | UARTLSR_THRE)
 	cmp	w2, #(UARTLSR_TEMT | UARTLSR_THRE)
 	b.ne	1b
 	mov	w2, #0xD		/* '\r' */
 	str	w2, [x1, #UARTTX]

 	/* Check if the transmit FIFO is full */
 2:	ldr	w2, [x1, #UARTLSR]
 	and	w2, w2, #(UARTLSR_TEMT | UARTLSR_THRE)
 	cmp	w2, #(UARTLSR_TEMT | UARTLSR_THRE)
 	b.ne	2b
 	str	w0, [x1, #UARTTX]
 	ret
 endfunc console_16550_core_putc

 	/* --------------------------------------------------------
 	 * int console_16550_putc(int c, console_16550_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 structure
 	 * Out : return -1 on error else return character.
 	 * Clobber list : x2
 	 * --------------------------------------------------------
 	 */
 func console_16550_putc
 #if ENABLE_ASSERTIONS
 	cmp	x1, #0
 	ASM_ASSERT(ne)
 #endif /* ENABLE_ASSERTIONS */
 	ldr	x1, [x1, #CONSOLE_T_16550_BASE]
 	b	console_16550_core_putc
 endfunc console_16550_putc

 	/* ---------------------------------------------
 	 * int console_16550_core_getc(uintptr_t base_addr)
 	 * Function to get a character from the console.
 	 * It returns the character grabbed on success
 	 * or -1 on if no character is available.
 	 * In :  x0 - console base address
 	 * Out : w0 - character if available, else -1
 	 * Clobber list : x0, x1
 	 * ---------------------------------------------
 	 */
 func console_16550_core_getc
 #if ENABLE_ASSERTIONS
 	cmp	x0, #0
 	ASM_ASSERT(ne)
 #endif /* ENABLE_ASSERTIONS */

 	/* Check if the receive FIFO is empty */
 1:	ldr	w1, [x0, #UARTLSR]
 	tbz	w1, #UARTLSR_RDR_BIT, no_char
 	ldr	w0, [x0, #UARTRX]
 	ret
 no_char:
 	mov	w0, #ERROR_NO_PENDING_CHAR
 	ret
 endfunc console_16550_core_getc

 	/* ---------------------------------------------
 	 * int console_16550_getc(console_16550_t *console)
 	 * Function to get a character from the console.
 	 * It returns the character grabbed on success
 	 * or -1 on if no character is available.
 	 * In :  x0 - pointer to console_t stucture
 	 * Out : w0 - character if available, else -1
 	 * Clobber list : x0, x1
 	 * ---------------------------------------------
 	 */
 func console_16550_getc
 #if ENABLE_ASSERTIONS
 	cmp	x1, #0
 	ASM_ASSERT(ne)
 #endif /* ENABLE_ASSERTIONS */
 	ldr	x0, [x0, #CONSOLE_T_16550_BASE]
 	b	console_16550_core_getc
 endfunc console_16550_getc

 	/* ---------------------------------------------
 	 * int console_16550_core_flush(uintptr_t base_addr)
 	 * Function to force a write of all buffered
 	 * data that hasn't been output.
 	 * In : x0 - console base address
 	 * Out : return -1 on error else return 0.
 	 * Clobber list : x0, x1
 	 * ---------------------------------------------
 	 */
 func console_16550_core_flush
 #if ENABLE_ASSERTIONS
 	cmp	x0, #0
 	ASM_ASSERT(ne)
 #endif /* ENABLE_ASSERTIONS */

 	/* Loop until the transmit FIFO is empty */
 1:	ldr	w1, [x0, #UARTLSR]
 	and	w1, w1, #(UARTLSR_TEMT | UARTLSR_THRE)
 	cmp	w1, #(UARTLSR_TEMT | UARTLSR_THRE)
 	b.ne	1b

 	mov	w0, #0
 	ret
 endfunc console_16550_core_flush

 	/* ---------------------------------------------
 	 * int console_16550_flush(console_pl011_t *console)
 	 * Function to force a write of all buffered
 	 * data that hasn't been output.
 	 * In : x0 - pointer to console_t structure
 	 * Out : return -1 on error else return 0.
 	 * Clobber list : x0, x1
 	 * ---------------------------------------------
 	 */
 func console_16550_flush
 #if ENABLE_ASSERTIONS
 	cmp	x0, #0
 	ASM_ASSERT(ne)
 #endif /* ENABLE_ASSERTIONS */
 	ldr	x0, [x0, #CONSOLE_T_16550_BASE]
 	b	console_16550_core_flush
 endfunc console_16550_flush
	/*
	* Copyright (c) 2015-2018, ARM Limited and Contributors. All rights reserved.
	*
	* SPDX-License-Identifier: BSD-3-Clause
	*/

	#include <arch.h>
	#include <asm_macros.S>
	#include <assert_macros.S>
	#include <console_macros.S>
	#include <uart_16550.h>

	/*
	* "core" functions are low-level implementations that don't require
	* writable memory and are thus safe to call in BL1 crash context.
	*/
	.globl console_16550_core_init
	.globl console_16550_core_putc
	.globl console_16550_core_getc
	.globl console_16550_core_flush

	.globl console_16550_putc
	.globl console_16550_getc
	.globl console_16550_flush

	/* -----------------------------------------------
	* int console_16550_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: x0 - console base address
	* w1 - Uart clock in Hz
	* w2 - Baud rate
	* Out: return 1 on success, 0 on error
	* Clobber list : x1, x2, x3
	* -----------------------------------------------
	*/
	func console_16550_core_init
	/* Check the input base address */
	cbz x0, init_fail
	/* Check baud rate and uart clock for sanity */
	cbz w1, init_fail
	cbz w2, init_fail

	/* Program the baudrate */
	/* Divisor = Uart clock / (16 * baudrate) */
	lsl w2, w2, #4
	udiv w2, w1, w2
	and w1, w2, #0xff /* w1 = DLL */
	lsr w2, w2, #8
	and w2, w2, #0xff /* w2 = DLLM */
	ldr w3, [x0, #UARTLCR]
	orr w3, w3, #UARTLCR_DLAB
	str w3, [x0, #UARTLCR] /* enable DLL, DLLM programming */
	str w1, [x0, #UARTDLL] /* program DLL */
	str w2, [x0, #UARTDLLM] /* program DLLM */
	mov w2, #~UARTLCR_DLAB
	and w3, w3, w2
	str w3, [x0, #UARTLCR] /* disable DLL, DLLM programming */

	/* 8n1 */
	mov w3, #3
	str w3, [x0, #UARTLCR]
	/* no interrupt */
	mov w3, #0
	str w3, [x0, #UARTIER]
	#ifdef TI_16550_MDR_QUIRK
	/* UART must be enabled on some platforms via the MDR register */
	str w3, [x0, #UARTMDR1]
	#endif /* TI_16550_MDR_QUIRK */
	/* enable fifo, DMA */
	mov w3, #(UARTFCR_FIFOEN \| UARTFCR_DMAEN)
	str w3, [x0, #UARTFCR]
	/* DTR + RTS */
	mov w3, #3
	str w3, [x0, #UARTMCR]
	mov w0, #1
	ret
	init_fail:
	mov w0, #0
	ret
	endfunc console_16550_core_init

	#if MULTI_CONSOLE_API
	.globl console_16550_register

	/* -----------------------------------------------
	* int console_16550_register(console_16550_t *console,
	uintptr_t base, uint32_t clk, uint32_t baud)
	* Function to initialize and register a new 16550
	* console. Storage passed in for the console struct
	* must be persistent (i.e. not from the stack).
	* In: x0 - UART register base address
	* w1 - UART clock in Hz
	* w2 - Baud rate
	* x3 - pointer to empty console_16550_t struct
	* Out: return 1 on success, 0 on error
	* Clobber list : x0, x1, x2, x6, x7, x14
	* -----------------------------------------------
	*/
	func console_16550_register
	mov x7, x30
	mov x6, x3
	cbz x6, register_fail
	str x0, [x6, #CONSOLE_T_16550_BASE]

	bl console_16550_core_init
	cbz x0, register_fail

	mov x0, x6
	mov x30, x7
	finish_console_register 16550

	register_fail:
	ret x7
	endfunc console_16550_register
	#else
	.globl console_core_init
	.globl console_core_putc
	.globl console_core_getc
	.globl console_core_flush
	.equ console_core_init,console_16550_core_init
	.equ console_core_putc,console_16550_core_putc
	.equ console_core_getc,console_16550_core_getc
	.equ console_core_flush,console_16550_core_flush
	#endif

	/* --------------------------------------------------------
	* int console_16550_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 : w0 - character to be printed
	* x1 - console base address
	* Out : return -1 on error else return character.
	* Clobber list : x2
	* --------------------------------------------------------
	*/
	func console_16550_core_putc
	#if ENABLE_ASSERTIONS
	cmp x1, #0
	ASM_ASSERT(ne)
	#endif /* ENABLE_ASSERTIONS */

	/* Prepend '\r' to '\n' */
	cmp w0, #0xA
	b.ne 2f
	/* Check if the transmit FIFO is full */
	1: ldr w2, [x1, #UARTLSR]
	and w2, w2, #(UARTLSR_TEMT \| UARTLSR_THRE)
	cmp w2, #(UARTLSR_TEMT \| UARTLSR_THRE)
	b.ne 1b
	mov w2, #0xD /* '\r' */
	str w2, [x1, #UARTTX]

	/* Check if the transmit FIFO is full */
	2: ldr w2, [x1, #UARTLSR]
	and w2, w2, #(UARTLSR_TEMT \| UARTLSR_THRE)
	cmp w2, #(UARTLSR_TEMT \| UARTLSR_THRE)
	b.ne 2b
	str w0, [x1, #UARTTX]
	ret
	endfunc console_16550_core_putc

	/* --------------------------------------------------------
	* int console_16550_putc(int c, console_16550_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 structure
	* Out : return -1 on error else return character.
	* Clobber list : x2
	* --------------------------------------------------------
	*/
	func console_16550_putc
	#if ENABLE_ASSERTIONS
	cmp x1, #0
	ASM_ASSERT(ne)
	#endif /* ENABLE_ASSERTIONS */
	ldr x1, [x1, #CONSOLE_T_16550_BASE]
	b console_16550_core_putc
	endfunc console_16550_putc

	/* ---------------------------------------------
	* int console_16550_core_getc(uintptr_t base_addr)
	* Function to get a character from the console.
	* It returns the character grabbed on success
	* or -1 on if no character is available.
	* In : x0 - console base address
	* Out : w0 - character if available, else -1
	* Clobber list : x0, x1
	* ---------------------------------------------
	*/
	func console_16550_core_getc
	#if ENABLE_ASSERTIONS
	cmp x0, #0
	ASM_ASSERT(ne)
	#endif /* ENABLE_ASSERTIONS */

	/* Check if the receive FIFO is empty */
	1: ldr w1, [x0, #UARTLSR]
	tbz w1, #UARTLSR_RDR_BIT, no_char
	ldr w0, [x0, #UARTRX]
	ret
	no_char:
	mov w0, #ERROR_NO_PENDING_CHAR
	ret
	endfunc console_16550_core_getc

	/* ---------------------------------------------
	* int console_16550_getc(console_16550_t *console)
	* Function to get a character from the console.
	* It returns the character grabbed on success
	* or -1 on if no character is available.
	* In : x0 - pointer to console_t stucture
	* Out : w0 - character if available, else -1
	* Clobber list : x0, x1
	* ---------------------------------------------
	*/
	func console_16550_getc
	#if ENABLE_ASSERTIONS
	cmp x1, #0
	ASM_ASSERT(ne)
	#endif /* ENABLE_ASSERTIONS */
	ldr x0, [x0, #CONSOLE_T_16550_BASE]
	b console_16550_core_getc
	endfunc console_16550_getc

	/* ---------------------------------------------
	* int console_16550_core_flush(uintptr_t base_addr)
	* Function to force a write of all buffered
	* data that hasn't been output.
	* In : x0 - console base address
	* Out : return -1 on error else return 0.
	* Clobber list : x0, x1
	* ---------------------------------------------
	*/
	func console_16550_core_flush
	#if ENABLE_ASSERTIONS
	cmp x0, #0
	ASM_ASSERT(ne)
	#endif /* ENABLE_ASSERTIONS */

	/* Loop until the transmit FIFO is empty */
	1: ldr w1, [x0, #UARTLSR]
	and w1, w1, #(UARTLSR_TEMT \| UARTLSR_THRE)
	cmp w1, #(UARTLSR_TEMT \| UARTLSR_THRE)
	b.ne 1b

	mov w0, #0
	ret
	endfunc console_16550_core_flush

	/* ---------------------------------------------
	* int console_16550_flush(console_pl011_t *console)
	* Function to force a write of all buffered
	* data that hasn't been output.
	* In : x0 - pointer to console_t structure
	* Out : return -1 on error else return 0.
	* Clobber list : x0, x1
	* ---------------------------------------------
	*/
	func console_16550_flush
	#if ENABLE_ASSERTIONS
	cmp x0, #0
	ASM_ASSERT(ne)
	#endif /* ENABLE_ASSERTIONS */
	ldr x0, [x0, #CONSOLE_T_16550_BASE]
	b console_16550_core_flush
	endfunc console_16550_flush