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1 /*
2  * NS16550 Serial Port
3  * originally from linux source (arch/powerpc/boot/ns16550.h)
4  *
5  * Cleanup and unification
6  * (C) 2009 by Detlev Zundel, DENX Software Engineering GmbH
7  *
8  * modified slightly to
9  * have addresses as offsets from CONFIG_SYS_ISA_BASE
10  * added a few more definitions
11  * added prototypes for ns16550.c
12  * reduced no of com ports to 2
13  * modifications (c) Rob Taylor, Flying Pig Systems. 2000.
14  *
15  * added support for port on 64-bit bus
16  * by Richard Danter (richard.danter@windriver.com), (C) 2005 Wind River Systems
17  */
18 
19 /*
20  * Note that the following macro magic uses the fact that the compiler
21  * will not allocate storage for arrays of size 0
22  */
23 
24 #include <linux/types.h>
25 
26 #ifdef CONFIG_DM_SERIAL
27 /*
28  * For driver model we always use one byte per register, and sort out the
29  * differences in the driver
30  */
31 #define CONFIG_SYS_NS16550_REG_SIZE (-1)
32 #endif
33 
34 #if !defined(CONFIG_SYS_NS16550_REG_SIZE) || (CONFIG_SYS_NS16550_REG_SIZE == 0)
35 #error "Please define NS16550 registers size."
36 #elif defined(CONFIG_SYS_NS16550_MEM32) && !defined(CONFIG_DM_SERIAL)
37 #define UART_REG(x) u32 x
38 #elif (CONFIG_SYS_NS16550_REG_SIZE > 0)
39 #define UART_REG(x)						   \
40 	unsigned char prepad_##x[CONFIG_SYS_NS16550_REG_SIZE - 1]; \
41 	unsigned char x;
42 #elif (CONFIG_SYS_NS16550_REG_SIZE < 0)
43 #define UART_REG(x)							\
44 	unsigned char x;						\
45 	unsigned char postpad_##x[-CONFIG_SYS_NS16550_REG_SIZE - 1];
46 #endif
47 
48 /**
49  * struct ns16550_platdata - information about a NS16550 port
50  *
51  * @base:		Base register address
52  * @reg_width:		IO accesses size of registers (in bytes)
53  * @reg_shift:		Shift size of registers (0=byte, 1=16bit, 2=32bit...)
54  * @clock:		UART base clock speed in Hz
55  * @bdf:		PCI slot/function (pci_dev_t)
56  */
57 struct ns16550_platdata {
58 	unsigned long base;
59 	int reg_width;
60 	int reg_shift;
61 	int reg_offset;
62 	int clock;
63 	u32 fcr;
64 #if defined(CONFIG_PCI) && defined(CONFIG_SPL)
65 	int bdf;
66 #endif
67 };
68 
69 struct udevice;
70 
71 struct NS16550 {
72 	UART_REG(rbr);		/* 0 */
73 	UART_REG(ier);		/* 1 */
74 	UART_REG(fcr);		/* 2 */
75 	UART_REG(lcr);		/* 3 */
76 	UART_REG(mcr);		/* 4 */
77 	UART_REG(lsr);		/* 5 */
78 	UART_REG(msr);		/* 6 */
79 	UART_REG(spr);		/* 7 */
80 #ifdef CONFIG_SOC_DA8XX
81 	UART_REG(reg8);		/* 8 */
82 	UART_REG(reg9);		/* 9 */
83 	UART_REG(revid1);	/* A */
84 	UART_REG(revid2);	/* B */
85 	UART_REG(pwr_mgmt);	/* C */
86 	UART_REG(mdr1);		/* D */
87 #else
88 	UART_REG(mdr1);		/* 8 */
89 	UART_REG(reg9);		/* 9 */
90 	UART_REG(regA);		/* A */
91 	UART_REG(regB);		/* B */
92 	UART_REG(regC);		/* C */
93 	UART_REG(regD);		/* D */
94 	UART_REG(regE);		/* E */
95 	UART_REG(uasr);		/* F */
96 	UART_REG(scr);		/* 10*/
97 	UART_REG(ssr);		/* 11*/
98 #endif
99 #ifdef CONFIG_DM_SERIAL
100 	struct ns16550_platdata *plat;
101 #endif
102 };
103 
104 #define thr rbr
105 #define iir fcr
106 #define dll rbr
107 #define dlm ier
108 
109 typedef struct NS16550 *NS16550_t;
110 
111 /*
112  * These are the definitions for the FIFO Control Register
113  */
114 #define UART_FCR_FIFO_EN	0x01 /* Fifo enable */
115 #define UART_FCR_CLEAR_RCVR	0x02 /* Clear the RCVR FIFO */
116 #define UART_FCR_CLEAR_XMIT	0x04 /* Clear the XMIT FIFO */
117 #define UART_FCR_DMA_SELECT	0x08 /* For DMA applications */
118 #define UART_FCR_TRIGGER_MASK	0xC0 /* Mask for the FIFO trigger range */
119 #define UART_FCR_TRIGGER_1	0x00 /* Mask for trigger set at 1 */
120 #define UART_FCR_TRIGGER_4	0x40 /* Mask for trigger set at 4 */
121 #define UART_FCR_TRIGGER_8	0x80 /* Mask for trigger set at 8 */
122 #define UART_FCR_TRIGGER_14	0xC0 /* Mask for trigger set at 14 */
123 
124 #define UART_FCR_RXSR		0x02 /* Receiver soft reset */
125 #define UART_FCR_TXSR		0x04 /* Transmitter soft reset */
126 
127 /* Ingenic JZ47xx specific UART-enable bit. */
128 #define UART_FCR_UME		0x10
129 
130 /* Clear & enable FIFOs */
131 #define UART_FCR_DEFVAL (UART_FCR_FIFO_EN | \
132 			UART_FCR_RXSR |	\
133 			UART_FCR_TXSR)
134 
135 /*
136  * These are the definitions for the Modem Control Register
137  */
138 #define UART_MCR_DTR	0x01		/* DTR   */
139 #define UART_MCR_RTS	0x02		/* RTS   */
140 #define UART_MCR_OUT1	0x04		/* Out 1 */
141 #define UART_MCR_OUT2	0x08		/* Out 2 */
142 #define UART_MCR_LOOP	0x10		/* Enable loopback test mode */
143 #define UART_MCR_AFE	0x20		/* Enable auto-RTS/CTS */
144 
145 #define UART_MCR_DMA_EN	0x04
146 #define UART_MCR_TX_DFR	0x08
147 
148 /*
149  * These are the definitions for the Line Control Register
150  *
151  * Note: if the word length is 5 bits (UART_LCR_WLEN5), then setting
152  * UART_LCR_STOP will select 1.5 stop bits, not 2 stop bits.
153  */
154 #define UART_LCR_WLS_MSK 0x03		/* character length select mask */
155 #define UART_LCR_WLS_5	0x00		/* 5 bit character length */
156 #define UART_LCR_WLS_6	0x01		/* 6 bit character length */
157 #define UART_LCR_WLS_7	0x02		/* 7 bit character length */
158 #define UART_LCR_WLS_8	0x03		/* 8 bit character length */
159 #define UART_LCR_STB	0x04		/* # stop Bits, off=1, on=1.5 or 2) */
160 #define UART_LCR_PEN	0x08		/* Parity eneble */
161 #define UART_LCR_EPS	0x10		/* Even Parity Select */
162 #define UART_LCR_STKP	0x20		/* Stick Parity */
163 #define UART_LCR_SBRK	0x40		/* Set Break */
164 #define UART_LCR_BKSE	0x80		/* Bank select enable */
165 #define UART_LCR_DLAB	0x80		/* Divisor latch access bit */
166 
167 /*
168  * These are the definitions for the Line Status Register
169  */
170 #define UART_LSR_DR	0x01		/* Data ready */
171 #define UART_LSR_OE	0x02		/* Overrun */
172 #define UART_LSR_PE	0x04		/* Parity error */
173 #define UART_LSR_FE	0x08		/* Framing error */
174 #define UART_LSR_BI	0x10		/* Break */
175 #define UART_LSR_THRE	0x20		/* Xmit holding register empty */
176 #define UART_LSR_TEMT	0x40		/* Xmitter empty */
177 #define UART_LSR_ERR	0x80		/* Error */
178 
179 #define UART_MSR_DCD	0x80		/* Data Carrier Detect */
180 #define UART_MSR_RI	0x40		/* Ring Indicator */
181 #define UART_MSR_DSR	0x20		/* Data Set Ready */
182 #define UART_MSR_CTS	0x10		/* Clear to Send */
183 #define UART_MSR_DDCD	0x08		/* Delta DCD */
184 #define UART_MSR_TERI	0x04		/* Trailing edge ring indicator */
185 #define UART_MSR_DDSR	0x02		/* Delta DSR */
186 #define UART_MSR_DCTS	0x01		/* Delta CTS */
187 
188 /*
189  * These are the definitions for the Interrupt Identification Register
190  */
191 #define UART_IIR_NO_INT	0x01	/* No interrupts pending */
192 #define UART_IIR_ID	0x06	/* Mask for the interrupt ID */
193 
194 #define UART_IIR_MSI	0x00	/* Modem status interrupt */
195 #define UART_IIR_THRI	0x02	/* Transmitter holding register empty */
196 #define UART_IIR_RDI	0x04	/* Receiver data interrupt */
197 #define UART_IIR_RLSI	0x06	/* Receiver line status interrupt */
198 
199 /*
200  * These are the definitions for the Interrupt Enable Register
201  */
202 #define UART_IER_MSI	0x08	/* Enable Modem status interrupt */
203 #define UART_IER_RLSI	0x04	/* Enable receiver line status interrupt */
204 #define UART_IER_THRI	0x02	/* Enable Transmitter holding register int. */
205 #define UART_IER_RDI	0x01	/* Enable receiver data interrupt */
206 
207 /* useful defaults for LCR */
208 #define UART_LCR_8N1	0x03
209 
210 void NS16550_init(NS16550_t com_port, int baud_divisor);
211 void NS16550_putc(NS16550_t com_port, char c);
212 char NS16550_getc(NS16550_t com_port);
213 int NS16550_tstc(NS16550_t com_port);
214 void NS16550_reinit(NS16550_t com_port, int baud_divisor);
215 
216 /**
217  * ns16550_calc_divisor() - calculate the divisor given clock and baud rate
218  *
219  * Given the UART input clock and required baudrate, calculate the divisor
220  * that should be used.
221  *
222  * @port:	UART port
223  * @clock:	UART input clock speed in Hz
224  * @baudrate:	Required baud rate
225  * @return baud rate divisor that should be used
226  */
227 int ns16550_calc_divisor(NS16550_t port, int clock, int baudrate);
228 
229 /**
230  * ns16550_serial_ofdata_to_platdata() - convert DT to platform data
231  *
232  * Decode a device tree node for an ns16550 device. This includes the
233  * register base address and register shift properties. The caller must set
234  * up the clock frequency.
235  *
236  * @dev:	dev to decode platform data for
237  * @return:	0 if OK, -EINVAL on error
238  */
239 int ns16550_serial_ofdata_to_platdata(struct udevice *dev);
240 
241 /**
242  * ns16550_serial_probe() - probe a serial port
243  *
244  * This sets up the serial port ready for use, except for the baud rate
245  * @return 0, or -ve on error
246  */
247 int ns16550_serial_probe(struct udevice *dev);
248 
249 /**
250  * struct ns16550_serial_ops - ns16550 serial operations
251  *
252  * These should be used by the client driver for the driver's 'ops' member
253  */
254 extern const struct dm_serial_ops ns16550_serial_ops;
255