UART: add CSR SiRFprimaII SoC on-chip uart drivers

SiRFprimaII is the latest generation application processor from CSR’s
multi-function SoC product family.
The SoC support codes are in arch/arm/mach-prima2 from Linux mainline
3.0.

There are three dedicated UARTs in system. This patch adds basic driver
support for them.

It has used the newest pinmux subsystem from Linus Walleij.

Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Rong Wang <Rong.Wang@csr.com>
Signed-off-by: Bin Shi <Bin.Shi@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/tty/serial/Kconfig

@@ -535,6 +535,27 @@ config SERIAL_S5PV210
 	help
 	  Serial port support for Samsung's S5P Family of SoC's
 
+config SERIAL_SIRFSOC
+        tristate "SiRF SoC Platform Serial port support"
+        depends on ARM && ARCH_PRIMA2
+        select SERIAL_CORE
+        help
+          Support for the on-chip UART on the CSR SiRFprimaII series,
+          providing /dev/ttySiRF0, 1 and 2 (note, some machines may not
+          provide all of these ports, depending on how the serial port
+          pins are configured).
+
+config SERIAL_SIRFSOC_CONSOLE
+        bool "Support for console on SiRF SoC serial port"
+        depends on SERIAL_SIRFSOC=y
+        select SERIAL_CORE_CONSOLE
+        help
+          Even if you say Y here, the currently visible virtual console
+          (/dev/tty0) will still be used as the system console by default, but
+          you can alter that using a kernel command line option such as
+          "console=ttySiRFx". (Try "man bootparam" or see the documentation of
+          your boot loader about how to pass options to the kernel at
+          boot time.)
 
 config SERIAL_MAX3100
 	tristate "MAX3100 support"

drivers/tty/serial/Makefile

@@ -94,3 +94,4 @@ obj-$(CONFIG_SERIAL_MSM_SMD)	+= msm_smd_tty.o
 obj-$(CONFIG_SERIAL_MXS_AUART) += mxs-auart.o
 obj-$(CONFIG_SERIAL_LANTIQ)	+= lantiq.o
 obj-$(CONFIG_SERIAL_XILINX_PS_UART) += xilinx_uartps.o
+obj-$(CONFIG_SERIAL_SIRFSOC) += sirfsoc_uart.o

drivers/tty/serial/sirfsoc_uart.h

+/*
+ * Drivers for CSR SiRFprimaII onboard UARTs.
+ *
+ * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
+ *
+ * Licensed under GPLv2 or later.
+ */
+#include <linux/bitops.h>
+
+/* UART Register Offset Define */
+#define SIRFUART_LINE_CTRL			0x0040
+#define SIRFUART_TX_RX_EN			0x004c
+#define SIRFUART_DIVISOR			0x0050
+#define SIRFUART_INT_EN				0x0054
+#define SIRFUART_INT_STATUS			0x0058
+#define SIRFUART_TX_DMA_IO_CTRL			0x0100
+#define SIRFUART_TX_DMA_IO_LEN			0x0104
+#define SIRFUART_TX_FIFO_CTRL			0x0108
+#define SIRFUART_TX_FIFO_LEVEL_CHK		0x010C
+#define SIRFUART_TX_FIFO_OP			0x0110
+#define SIRFUART_TX_FIFO_STATUS			0x0114
+#define SIRFUART_TX_FIFO_DATA			0x0118
+#define SIRFUART_RX_DMA_IO_CTRL			0x0120
+#define SIRFUART_RX_DMA_IO_LEN			0x0124
+#define SIRFUART_RX_FIFO_CTRL			0x0128
+#define SIRFUART_RX_FIFO_LEVEL_CHK		0x012C
+#define SIRFUART_RX_FIFO_OP			0x0130
+#define SIRFUART_RX_FIFO_STATUS			0x0134
+#define SIRFUART_RX_FIFO_DATA			0x0138
+#define SIRFUART_AFC_CTRL			0x0140
+#define SIRFUART_SWH_DMA_IO			0x0148
+
+/* UART Line Control Register */
+#define SIRFUART_DATA_BIT_LEN_MASK		0x3
+#define SIRFUART_DATA_BIT_LEN_5			BIT(0)
+#define SIRFUART_DATA_BIT_LEN_6			1
+#define SIRFUART_DATA_BIT_LEN_7			2
+#define SIRFUART_DATA_BIT_LEN_8			3
+#define SIRFUART_STOP_BIT_LEN_1			0
+#define SIRFUART_STOP_BIT_LEN_2			BIT(2)
+#define SIRFUART_PARITY_EN			BIT(3)
+#define SIRFUART_EVEN_BIT			BIT(4)
+#define SIRFUART_STICK_BIT_MASK			(7 << 3)
+#define SIRFUART_STICK_BIT_NONE			(0 << 3)
+#define SIRFUART_STICK_BIT_EVEN			BIT(3)
+#define SIRFUART_STICK_BIT_ODD			(3 << 3)
+#define SIRFUART_STICK_BIT_MARK			(5 << 3)
+#define SIRFUART_STICK_BIT_SPACE		(7 << 3)
+#define SIRFUART_SET_BREAK			BIT(6)
+#define SIRFUART_LOOP_BACK			BIT(7)
+#define SIRFUART_PARITY_MASK			(7 << 3)
+#define SIRFUART_DUMMY_READ			BIT(16)
+
+#define SIRFSOC_UART_RX_TIMEOUT(br, to)	(((br) * (((to) + 999) / 1000)) / 1000)
+#define SIRFUART_RECV_TIMEOUT_MASK	(0xFFFF << 16)
+#define SIRFUART_RECV_TIMEOUT(x)	(((x) & 0xFFFF) << 16)
+
+/* UART Auto Flow Control */
+#define SIRFUART_AFC_RX_THD_MASK		0x000000FF
+#define SIRFUART_AFC_RX_EN			BIT(8)
+#define SIRFUART_AFC_TX_EN			BIT(9)
+#define SIRFUART_CTS_CTRL			BIT(10)
+#define SIRFUART_RTS_CTRL			BIT(11)
+#define SIRFUART_CTS_IN_STATUS			BIT(12)
+#define SIRFUART_RTS_OUT_STATUS			BIT(13)
+
+/* UART Interrupt Enable Register */
+#define SIRFUART_RX_DONE_INT			BIT(0)
+#define SIRFUART_TX_DONE_INT			BIT(1)
+#define SIRFUART_RX_OFLOW_INT			BIT(2)
+#define SIRFUART_TX_ALLOUT_INT			BIT(3)
+#define SIRFUART_RX_IO_DMA_INT			BIT(4)
+#define SIRFUART_TX_IO_DMA_INT			BIT(5)
+#define SIRFUART_RXFIFO_FULL_INT		BIT(6)
+#define SIRFUART_TXFIFO_EMPTY_INT		BIT(7)
+#define SIRFUART_RXFIFO_THD_INT			BIT(8)
+#define SIRFUART_TXFIFO_THD_INT			BIT(9)
+#define SIRFUART_FRM_ERR_INT			BIT(10)
+#define SIRFUART_RXD_BREAK_INT			BIT(11)
+#define SIRFUART_RX_TIMEOUT_INT			BIT(12)
+#define SIRFUART_PARITY_ERR_INT			BIT(13)
+#define SIRFUART_CTS_INT_EN			BIT(14)
+#define SIRFUART_RTS_INT_EN			BIT(15)
+
+/* UART Interrupt Status Register */
+#define SIRFUART_RX_DONE			BIT(0)
+#define SIRFUART_TX_DONE			BIT(1)
+#define SIRFUART_RX_OFLOW			BIT(2)
+#define SIRFUART_TX_ALL_EMPTY			BIT(3)
+#define SIRFUART_DMA_IO_RX_DONE			BIT(4)
+#define SIRFUART_DMA_IO_TX_DONE			BIT(5)
+#define SIRFUART_RXFIFO_FULL			BIT(6)
+#define SIRFUART_TXFIFO_EMPTY			BIT(7)
+#define SIRFUART_RXFIFO_THD_REACH		BIT(8)
+#define SIRFUART_TXFIFO_THD_REACH		BIT(9)
+#define SIRFUART_FRM_ERR			BIT(10)
+#define SIRFUART_RXD_BREAK			BIT(11)
+#define SIRFUART_RX_TIMEOUT			BIT(12)
+#define SIRFUART_PARITY_ERR			BIT(13)
+#define SIRFUART_CTS_CHANGE			BIT(14)
+#define SIRFUART_RTS_CHANGE			BIT(15)
+#define SIRFUART_PLUG_IN			BIT(16)
+
+#define SIRFUART_ERR_INT_STAT					\
+				(SIRFUART_RX_OFLOW |		\
+				SIRFUART_FRM_ERR |		\
+				SIRFUART_RXD_BREAK |		\
+				SIRFUART_PARITY_ERR)
+#define SIRFUART_ERR_INT_EN					\
+				(SIRFUART_RX_OFLOW_INT |	\
+				SIRFUART_FRM_ERR_INT |		\
+				SIRFUART_RXD_BREAK_INT |	\
+				SIRFUART_PARITY_ERR_INT)
+#define SIRFUART_TX_INT_EN	SIRFUART_TXFIFO_EMPTY_INT
+#define SIRFUART_RX_IO_INT_EN					\
+				(SIRFUART_RX_TIMEOUT_INT |	\
+				SIRFUART_RXFIFO_THD_INT |	\
+				SIRFUART_RXFIFO_FULL_INT |	\
+				SIRFUART_ERR_INT_EN)
+
+/* UART FIFO Register */
+#define SIRFUART_TX_FIFO_STOP			0x0
+#define SIRFUART_TX_FIFO_RESET			0x1
+#define SIRFUART_TX_FIFO_START			0x2
+#define SIRFUART_RX_FIFO_STOP			0x0
+#define SIRFUART_RX_FIFO_RESET			0x1
+#define SIRFUART_RX_FIFO_START			0x2
+#define SIRFUART_TX_MODE_DMA			0
+#define SIRFUART_TX_MODE_IO			1
+#define SIRFUART_RX_MODE_DMA			0
+#define SIRFUART_RX_MODE_IO			1
+
+#define SIRFUART_RX_EN				0x1
+#define SIRFUART_TX_EN				0x2
+
+/* Generic Definitions */
+#define SIRFSOC_UART_NAME			"ttySiRF"
+#define SIRFSOC_UART_MAJOR			0
+#define SIRFSOC_UART_MINOR			0
+#define SIRFUART_PORT_NAME			"sirfsoc-uart"
+#define SIRFUART_MAP_SIZE			0x200
+#define SIRFSOC_UART_NR				3
+#define SIRFSOC_PORT_TYPE			0xa5
+
+/* Baud Rate Calculation */
+#define SIRF_MIN_SAMPLE_DIV			0xf
+#define SIRF_MAX_SAMPLE_DIV			0x3f
+#define SIRF_IOCLK_DIV_MAX			0xffff
+#define SIRF_SAMPLE_DIV_SHIFT			16
+#define SIRF_IOCLK_DIV_MASK			0xffff
+#define SIRF_SAMPLE_DIV_MASK			0x3f0000
+#define SIRF_BAUD_RATE_SUPPORT_NR		18
+
+/* For Fast Baud Rate Calculation */
+struct sirfsoc_baudrate_to_regv {
+	unsigned int baud_rate;
+	unsigned int reg_val;
+};
+
+struct sirfsoc_uart_port {
+	unsigned char			hw_flow_ctrl;
+	unsigned char			ms_enabled;
+
+	struct uart_port		port;
+	struct pinmux			*pmx;
+};
+
+/* Hardware Flow Control */
+#define SIRFUART_AFC_CTRL_RX_THD	0x70
+
+/* Register Access Control */
+#define portaddr(port, reg)		((port)->membase + (reg))
+#define rd_regb(port, reg)		(__raw_readb(portaddr(port, reg)))
+#define rd_regl(port, reg)		(__raw_readl(portaddr(port, reg)))
+#define wr_regb(port, reg, val)		__raw_writeb(val, portaddr(port, reg))
+#define wr_regl(port, reg, val)		__raw_writel(val, portaddr(port, reg))
+
+/* UART Port Mask */
+#define SIRFUART_FIFOLEVEL_MASK(port)	((port->line == 1) ? (0x1f) : (0x7f))
+#define SIRFUART_FIFOFULL_MASK(port)	((port->line == 1) ? (0x20) : (0x80))
+#define SIRFUART_FIFOEMPTY_MASK(port)	((port->line == 1) ? (0x40) : (0x100))
+
+/* I/O Mode */
+#define SIRFSOC_UART_IO_RX_MAX_CNT		256
+#define SIRFSOC_UART_IO_TX_REASONABLE_CNT	6