FR_TXFF 83 bsp/boot/arm/integrator/debug.c while (UART_FR & FR_TXFF) FR_TXFF 123 bsp/drv/dev/serial/pl011.c while (bus_read_32(UART_FR) & FR_TXFF) FR_TXFF 51 bsp/hal/arm/integrator/diag.c while (UART_FR & FR_TXFF)