linux/arch/arm/include/debug/zynq.S
Arun Chandran 974a2aba99 ARM: zynq: Fix earlyprintk in big endian mode
earlyprintk messages are not appearing on the terminal
emulator during a big endian kernel boot. In BE mode
sending full words to UART will result in unprintable
characters as they are byte swapped versions of printable
ones. So send only bytes.

Signed-off-by: Arun Chandran <achandran@mvista.com>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
2015-07-22 09:37:58 +02:00

57 lines
1.6 KiB
ArmAsm

/*
* Debugging macro include header
*
* Copyright (C) 2011 Xilinx
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#define UART_CR_OFFSET 0x00 /* Control Register [8:0] */
#define UART_SR_OFFSET 0x2C /* Channel Status [11:0] */
#define UART_FIFO_OFFSET 0x30 /* FIFO [15:0] or [7:0] */
#define UART_SR_TXFULL 0x00000010 /* TX FIFO full */
#define UART_SR_TXEMPTY 0x00000008 /* TX FIFO empty */
#define UART0_PHYS 0xE0000000
#define UART0_VIRT 0xF0000000
#define UART1_PHYS 0xE0001000
#define UART1_VIRT 0xF0001000
#if IS_ENABLED(CONFIG_DEBUG_ZYNQ_UART1)
# define LL_UART_PADDR UART1_PHYS
# define LL_UART_VADDR UART1_VIRT
#else
# define LL_UART_PADDR UART0_PHYS
# define LL_UART_VADDR UART0_VIRT
#endif
.macro addruart, rp, rv, tmp
ldr \rp, =LL_UART_PADDR @ physical
ldr \rv, =LL_UART_VADDR @ virtual
.endm
.macro senduart,rd,rx
strb \rd, [\rx, #UART_FIFO_OFFSET] @ TXDATA
.endm
.macro waituart,rd,rx
1001: ldr \rd, [\rx, #UART_SR_OFFSET]
ARM_BE8( rev \rd, \rd )
tst \rd, #UART_SR_TXEMPTY
beq 1001b
.endm
.macro busyuart,rd,rx
1002: ldr \rd, [\rx, #UART_SR_OFFSET] @ get status register
ARM_BE8( rev \rd, \rd )
tst \rd, #UART_SR_TXFULL @
bne 1002b @ wait if FIFO is full
.endm