uart: 16550: Fix getc
tbz check for RDR status is to check for a bit being zero.
Unfortunately, we are using a mask rather than the bit position.
Further as per http://www.ti.com/lit/ds/symlink/pc16550d.pdf (page 17),
LSR register bit 0 is Data ready status (RDR), not bit position 2.
Update the same to match the specification.
Reported-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
diff --git a/drivers/ti/uart/aarch64/16550_console.S b/drivers/ti/uart/aarch64/16550_console.S
index 0535381..8466482 100644
--- a/drivers/ti/uart/aarch64/16550_console.S
+++ b/drivers/ti/uart/aarch64/16550_console.S
@@ -146,7 +146,7 @@
func console_core_getc
/* Check if the receive FIFO is empty */
1: ldr w1, [x0, #UARTLSR]
- tbz w1, #UARTLSR_RDR, 1b
+ tbz w1, #UARTLSR_RDR_BIT, 1b
ldr w0, [x0, #UARTRX]
ret
getc_error:
diff --git a/include/drivers/ti/uart/uart_16550.h b/include/drivers/ti/uart/uart_16550.h
index 2c814ef..773e2f1 100644
--- a/include/drivers/ti/uart/uart_16550.h
+++ b/include/drivers/ti/uart/uart_16550.h
@@ -88,6 +88,7 @@
#define UARTLSR_FERR (1 << 3) /* Framing Error */
#define UARTLSR_PERR (1 << 3) /* Parity Error */
#define UARTLSR_OVRF (1 << 2) /* Rx Overrun Error */
-#define UARTLSR_RDR (1 << 2) /* Rx Data Ready */
+#define UARTLSR_RDR_BIT (0) /* Rx Data Ready Bit */
+#define UARTLSR_RDR (1 << UARTLSR_RDR_BIT) /* Rx Data Ready */
#endif /* __UART_16550_H__ */