Driver for 16550 UART interface

This patch adds driver for the 16550 UART interface. The driver is exposed
as a console, which platforms can use to dump their boot/crash logs.

Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>

1 files changed, 93 insertions, 0 deletions

diff --git a/include/drivers/ti/uart/uart_16550.h b/include/drivers/ti/uart/uart_16550.h
new file mode 100644
index 0000000..2c814ef
--- /dev/null
+++ b/include/drivers/ti/uart/uart_16550.h
@@ -0,0 +1,93 @@
+/*
+ * Copyright (c) 2015, ARM Limited and Contributors. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of ARM nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without specific
+ * prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __UART_16550_H__
+#define __UART_16550_H__
+
+/* UART16550 Registers */
+#define UARTTX			0x0
+#define UARTRX			0x0
+#define UARTDLL			0x0
+#define UARTIER			0x4
+#define UARTDLLM		0x4
+#define UARTIIR			0x8
+#define UARTFCR			0x8
+#define UARTLCR			0xc
+#define UARTMCR			0x10
+#define UARTLSR			0x14
+#define UARTMSR			0x18
+#define UARTSPR			0x1c
+#define UARTCSR			0x20
+#define UARTRXFIFOCFG		0x24
+#define UARTMIE			0x28
+#define UARTVNDR		0x2c
+#define UARTASR			0x3c
+
+/* FIFO Control Register bits */
+#define UARTFCR_FIFOMD_16450	(0 << 6)
+#define UARTFCR_FIFOMD_16550	(1 << 6)
+#define UARTFCR_RXTRIG_1	(0 << 6)
+#define UARTFCR_RXTRIG_4	(1 << 6)
+#define UARTFCR_RXTRIG_8	(2 << 6)
+#define UARTFCR_RXTRIG_16	(3 << 6)
+#define UARTFCR_TXTRIG_1	(0 << 4)
+#define UARTFCR_TXTRIG_4	(1 << 4)
+#define UARTFCR_TXTRIG_8	(2 << 4)
+#define UARTFCR_TXTRIG_16	(3 << 4)
+#define UARTFCR_DMAEN		(1 << 3)	/* Enable DMA mode */
+#define UARTFCR_TXCLR		(1 << 2)	/* Clear contents of Tx FIFO */
+#define UARTFCR_RXCLR		(1 << 1)	/* Clear contents of Rx FIFO */
+#define UARTFCR_FIFOEN		(1 << 0)	/* Enable the Tx/Rx FIFO */
+
+/* Line Control Register bits */
+#define UARTLCR_DLAB		(1 << 7)	/* Divisor Latch Access */
+#define UARTLCR_SETB		(1 << 6)	/* Set BREAK Condition */
+#define UARTLCR_SETP		(1 << 5)	/* Set Parity to LCR[4] */
+#define UARTLCR_EVEN		(1 << 4)	/* Even Parity Format */
+#define UARTLCR_PAR		(1 << 3)	/* Parity */
+#define UARTLCR_STOP		(1 << 2)	/* Stop Bit */
+#define UARTLCR_WORDSZ_5	0		/* Word Length of 5 */
+#define UARTLCR_WORDSZ_6	1		/* Word Length of 6 */
+#define UARTLCR_WORDSZ_7	2		/* Word Length of 7 */
+#define UARTLCR_WORDSZ_8	3		/* Word Length of 8 */
+
+/* Line Status Register bits */
+#define UARTLSR_RXFIFOEMT	(1 << 9)	/* Rx Fifo Empty */
+#define UARTLSR_TXFIFOFULL	(1 << 8)	/* Tx Fifo Full */
+#define UARTLSR_RXFIFOERR	(1 << 7)	/* Rx Fifo Error */
+#define UARTLSR_TEMT		(1 << 6)	/* Tx Shift Register Empty */
+#define UARTLSR_THRE		(1 << 5)	/* Tx Holding Register Empty */
+#define UARTLSR_BRK		(1 << 4)	/* Break Condition Detected */
+#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 */
+
+#endif	/* __UART_16550_H__ */