diff options
Diffstat (limited to 'xen/arch/arm/arm32/debug-8250.inc')
| -rw-r--r-- | xen/arch/arm/arm32/debug-8250.inc | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/xen/arch/arm/arm32/debug-8250.inc b/xen/arch/arm/arm32/debug-8250.inc new file mode 100644 index 0000000000..eb25882400 --- /dev/null +++ b/xen/arch/arm/arm32/debug-8250.inc @@ -0,0 +1,41 @@ +/* + * xen/arch/arm/arm32/debug-8250.inc + * + * 8250 specific debug code + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * 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. + */ + +#include <xen/8250-uart.h> + +/* 8250 UART wait UART to be ready to transmit + * rb: register which contains the UART base address + * rc: scratch register */ +.macro early_uart_ready rb rc +1: + ldr \rc, [\rb, #(UART_LSR << EARLY_UART_REG_SHIFT)] /* Read LSR */ + tst \rc, #UART_LSR_THRE /* Check Xmit holding register flag */ + beq 1b /* Wait for the UART to be ready */ +.endm + +/* 8250 UART transmit character + * rb: register which contains the UART base address + * rt: register which contains the character to transmit */ +.macro early_uart_transmit rb rt + str \rt, [\rb, #UART_THR] /* Write Transmit buffer */ +.endm + +/* + * Local variables: + * mode: ASM + * indent-tabs-mode: nil + * End: + */ |