linux/arch/arm/include/debug/imx.S
Johannes Berg 26e30c6489 ARM: imx: enable big endian mode
Enable ARM big-endian mode on mach-imx. This requires adding some
byte swapping in the debug functions (which otherwise hang forever)
and of course the secondary core bringup.

Tested (on top of 4.4) on i.MX6 HummingBoard quad-core (IMX6Q).

The patch is pretty much as suggested by Arnd Bergmann, thanks!

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2016-02-02 13:31:19 +08:00

51 lines
1.3 KiB
ArmAsm

/* arch/arm/mach-imx/include/mach/debug-macro.S
*
* Debugging macro include header
*
* Copyright (C) 1994-1999 Russell King
* Moved from linux/arch/arm/kernel/debug.S by Ben Dooks
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
*/
#include <asm/assembler.h>
#include "imx-uart.h"
/*
* FIXME: This is a copy of IMX_IO_P2V in hardware.h, and needs to
* stay sync with that. It's hard to maintain, and should be fixed
* globally for multi-platform build to use a fixed virtual address
* for low-level debug uart port across platforms.
*/
#define IMX_IO_P2V(x) ( \
(((x) & 0x80000000) >> 7) | \
(0xf4000000 + \
(((x) & 0x50000000) >> 6) + \
(((x) & 0x0b000000) >> 4) + \
(((x) & 0x000fffff))))
#define UART_VADDR IMX_IO_P2V(UART_PADDR)
.macro addruart, rp, rv, tmp
ldr \rp, =UART_PADDR @ physical
ldr \rv, =UART_VADDR @ virtual
.endm
.macro senduart,rd,rx
ARM_BE8(rev \rd, \rd)
str \rd, [\rx, #0x40] @ TXDATA
.endm
.macro waituart,rd,rx
.endm
.macro busyuart,rd,rx
1002: ldr \rd, [\rx, #0x98] @ SR2
ARM_BE8(rev \rd, \rd)
tst \rd, #1 << 3 @ TXDC
beq 1002b @ wait until transmit done
.endm