Hi,

AT91SAM9 based boards have something like this in their include/configs file:

#define CONFIG_ATMEL_USART 1 #undef CONFIG_USART0 #undef CONFIG_USART1 #undef CONFIG_USART2 #define CONFIG_USART3 1 /* USART 3 is DBGU */

these defines are used in drivers/serial/atmel_usart.c:

#if defined(CONFIG_USART0) # define USART_ID 0 # define USART_BASE USART0_BASE #elif defined(CONFIG_USART1) # define USART_ID 1 # define USART_BASE USART1_BASE #elif defined(CONFIG_USART2) # define USART_ID 2 # define USART_BASE USART2_BASE #elif defined(CONFIG_USART3) # define USART_ID 3 # define USART_BASE USART3_BASE #endif

USARTx_BASE is defined in arch/arm/include/asm/arch-at91/memory_map.h:

#define USART0_BASE AT91_USART0 #define USART1_BASE AT91_USART1 #define USART2_BASE AT91_USART2 #define USART3_BASE (AT91_BASE_SYS + AT91_DBGU) #define SPI0_BASE AT91_BASE_SPI (note that nothing else is defined in that file!)

AT91_USARTx finally comes from arch/arm/include/asm/arch-at91/at91sam*.h:

#define AT91_USART0 AT91SAM9260_BASE_US0 #define AT91_USART1 AT91SAM9260_BASE_US1 #define AT91_USART2 AT91SAM9260_BASE_US2 #define AT91_USART3 AT91SAM9260_BASE_US3 #define AT91_USART4 AT91SAM9260_BASE_US4 #define AT91_USART5 AT91SAM9260_BASE_US5

1. memory_map.h is misleading, it just defines a few USARTs and one SPI 2. equalling CONFIG_USART3 with the debug UART is plain wrong, the 9260 for example has 6 'regular' USARTs (0..5) plus the debug UART

I propose to make the following changes: 1. get rid of memory_map.h and the references to it, move the USART definitions to the respective at91sam*.h files 2. use DBU_BASE for the debug UART, leaving USART[0-5]_BASE to adress the 'regular' USARTs 3. use CONFIG_UARTDEBUG to indicate use of the debug UART for console output

Note for those that don't want to dig the datasheets: the debug UART is software compatible to the 'regular' USARTs as long as only asynchronous features are used (true for the atmel_usart.c driver)

Reinhard