xref: /haiku/src/system/kernel/arch/arm/arch_uart_pl011.cpp (revision 372a66634410cf0450e426716c14ad42d40c0da4)
1 /*
2  * Copyright 2011-2012 Haiku, Inc. All rights reserved.
3  * Distributed under the terms of the MIT License.
4  *
5  * Authors:
6  *		Alexander von Gluck, kallisti5@unixzen.com
7  */
8 
9 
10 #include <debug.h>
11 #include <arch/arm/reg.h>
12 #include <arch/generic/debug_uart.h>
13 #include <arch/arm/arch_uart_pl011.h>
14 //#include <board_config.h>
15 #include <new>
16 //#include <target/debugconfig.h>
17 
18 
19 #define PL01x_DR	0x00 // Data read or written
20 #define PL01x_RSR	0x04 // Receive status, read
21 #define PL01x_ECR	0x04 // Error clear, write
22 #define PL010_LCRH	0x08 // Line control, high
23 #define PL010_LCRM	0x0C // Line control, middle
24 #define PL010_LCRL	0x10 // Line control, low
25 #define PL010_CR	0x14 // Control
26 #define PL01x_FR	0x18 // Flag (r/o)
27 #define PL010_IIR	0x1C // Interrupt ID (r)
28 #define PL010_ICR	0x1C // Interrupt clear (w)
29 #define PL01x_ILPR	0x20 // IrDA low power
30 #define PL011_IBRD	0x24 // Interrupt baud rate divisor
31 #define PL011_FBRD	0x28 // Fractional baud rate divisor
32 #define PL011_LCRH	0x2C // Line control
33 #define PL011_CR	0x30 // Control
34 #define PL011_IFLS	0x34 // Interrupt fifo level
35 #define PL011_IMSC	0x38 // Interrupt mask
36 #define PL011_RIS	0x3C // Raw interrupt
37 #define PL011_MIS	0x40 // Masked interrupt
38 #define PL011_ICR	0x44 // Interrupt clear
39 #define PL011_DMACR	0x48 // DMA control register
40 
41 #define PL011_DR_OE		(1 << 11)
42 #define PL011_DR_BE		(1 << 10)
43 #define PL011_DR_PE		(1 << 9)
44 #define PL011_DR_FE		(1 << 8)
45 
46 #define PL01x_RSR_OE	0x08
47 #define PL01x_RSR_BE	0x04
48 #define PL01x_RSR_PE	0x02
49 #define PL01x_RSR_FE	0x01
50 
51 #define PL011_FR_RI		0x100
52 #define PL011_FR_TXFE	0x080
53 #define PL011_FR_RXFF	0x040
54 #define PL01x_FR_TXFF	0x020
55 #define PL01x_FR_RXFE	0x010
56 #define PL01x_FR_BUSY	0x008
57 #define PL01x_FR_DCD	0x004
58 #define PL01x_FR_DSR	0x002
59 #define PL01x_FR_CTS	0x001
60 #define PL01x_FR_TMSK	(PL01x_FR_TXFF | PL01x_FR_BUSY)
61 
62 #define PL011_CR_CTSEN	0x8000 // CTS flow control
63 #define PL011_CR_RTSEN	0x4000 // RTS flow control
64 #define PL011_CR_OUT2	0x2000 // OUT2
65 #define PL011_CR_OUT1	0x1000 // OUT1
66 #define PL011_CR_RTS	0x0800 // RTS
67 #define PL011_CR_DTR	0x0400 // DTR
68 #define PL011_CR_RXE	0x0200 // Receive enable
69 #define PL011_CR_TXE	0x0100 // Transmit enable
70 #define PL011_CR_LBE	0x0080 // Loopback enable
71 #define PL010_CR_RTIE	0x0040
72 #define PL010_CR_TIE	0x0020
73 #define PL010_CR_RIE	0x0010
74 #define PL010_CR_MSIE	0x0008
75 #define PL01x_CR_IIRLP	0x0004 // SIR low power mode
76 #define PL01x_CR_SIREN	0x0002 // SIR enable
77 #define PL01x_CR_UARTEN 0x0001 // UART enable
78 
79 #define PL011_LCRH_SPS		0x80
80 #define PL01x_LCRH_WLEN_8	0x60
81 #define PL01x_LCRH_WLEN_7	0x40
82 #define PL01x_LCRH_WLEN_6	0x20
83 #define PL01x_LCRH_WLEN_5	0x00
84 #define PL01x_LCRH_FEN		0x10
85 #define PL01x_LCRH_STP2		0x08
86 #define PL01x_LCRH_EPS		0x04
87 #define PL01x_LCRH_PEN		0x02
88 #define PL01x_LCRH_BRK		0x01
89 
90 #define PL010_IIR_RTIS	0x08
91 #define PL010_IIR_TIS	0x04
92 #define PL010_IIR_RIS	0x02
93 #define PL010_IIR_MIS	0x01
94 
95 #define PL011_IFLS_RX1_8	(0 << 3)
96 #define PL011_IFLS_RX2_8	(1 << 3)
97 #define PL011_IFLS_RX4_8	(2 << 3)
98 #define PL011_IFLS_RX6_8	(3 << 3)
99 #define PL011_IFLS_RX7_8	(4 << 3)
100 #define PL011_IFLS_TX1_8	(0 << 0)
101 #define PL011_IFLS_TX2_8	(1 << 0)
102 #define PL011_IFLS_TX4_8	(2 << 0)
103 #define PL011_IFLS_TX6_8	(3 << 0)
104 #define PL011_IFLS_TX7_8	(4 << 0)
105 
106 #define PL011_IFLS_RX_HALF	(5 << 3) // ST vendor only
107 #define PL011_IFLS_TX_HALF	(5 << 0) // ST vendor only
108 
109 #define PL011_OEIM		(1 << 10) // overrun error interrupt mask
110 #define PL011_BEIM		(1 << 9) // break error interrupt mask
111 #define PL011_PEIM		(1 << 8) // parity error interrupt mask
112 #define PL011_FEIM		(1 << 7) // framing error interrupt mask
113 #define PL011_RTIM		(1 << 6) // receive timeout interrupt mask
114 #define PL011_TXIM		(1 << 5) // transmit interrupt mask
115 #define PL011_RXIM		(1 << 4) // receive interrupt mask
116 #define PL011_DSRMIM	(1 << 3) // DSR interrupt mask
117 #define PL011_DCDMIM	(1 << 2) // DCD interrupt mask
118 #define PL011_CTSMIM	(1 << 1) // CTS interrupt mask
119 #define PL011_RIMIM		(1 << 0) // RI interrupt mask
120 
121 #define PL011_OEIS		(1 << 10) // overrun error interrupt state
122 #define PL011_BEIS		(1 << 9) // break error interrupt state
123 #define PL011_PEIS		(1 << 8) // parity error interrupt state
124 #define PL011_FEIS		(1 << 7) // framing error interrupt	state
125 #define PL011_RTIS		(1 << 6) // receive timeout interrupt state
126 #define PL011_TXIS		(1 << 5) // transmit interrupt state
127 #define PL011_RXIS		(1 << 4) // receive interrupt state
128 #define PL011_DSRMIS	(1 << 3) // DSR interrupt state
129 #define PL011_DCDMIS	(1 << 2) // DCD interrupt state
130 #define PL011_CTSMIS	(1 << 1) // CTS interrupt state
131 #define PL011_RIMIS		(1 << 0) // RI interrupt state
132 
133 #define PL011_OEIC		(1 << 10) // overrun error interrupt clear
134 #define PL011_BEIC		(1 << 9) // break error interrupt clear
135 #define PL011_PEIC		(1 << 8) // parity error interrupt clear
136 #define PL011_FEIC		(1 << 7) // framing error interrupt clear
137 #define PL011_RTIC		(1 << 6) // receive timeout interrupt clear
138 #define PL011_TXIC		(1 << 5) // transmit interrupt clear
139 #define PL011_RXIC		(1 << 4) // receive interrupt clear
140 #define PL011_DSRMIC	(1 << 3) // DSR interrupt clear
141 #define PL011_DCDMIC	(1 << 2) // DCD interrupt clear
142 #define PL011_CTSMIC	(1 << 1) // CTS interrupt clear
143 #define PL011_RIMIC		(1 << 0) // RI interrupt clear
144 
145 #define PL011_DMAONERR	(1 << 2) // disable dma on err
146 #define PL011_TXDMAE	(1 << 1) // enable transmit dma
147 #define PL011_RXDMAE	(1 << 0) // enable receive dma
148 
149 
150 ArchUARTPL011::ArchUARTPL011(addr_t base, int64 clock)
151 	: DebugUART(base, clock)
152 {
153 	Barrier();
154 
155 	// ** Loopback test
156 	uint32 cr = PL01x_CR_UARTEN;
157 		// Enable UART
158 	cr |= PL011_CR_TXE;
159 		// Enable TX
160 	cr |= PL011_CR_LBE;
161 		// Enable Loopback mode
162 	Out32(PL011_CR, cr);
163 
164 	Out32(PL011_FBRD, 0);
165 	Out32(PL011_IBRD, 1);
166 	Out32(PL011_LCRH, 0); // TODO: ST is different tx, rx lcr
167 
168 	// Write a 0 to the port and wait for confim..
169 	Out32(PL01x_DR, 0);
170 
171 	while (In32(PL01x_FR) & PL01x_FR_BUSY)
172 		Barrier();
173 
174 	// ** Disable loopback, enable uart
175 	cr = PL01x_CR_UARTEN | PL011_CR_RXE | PL011_CR_TXE;
176 	Out32(PL011_CR, cr);
177 
178 	// ** Clear interrupts
179 	Out32(PL011_ICR, PL011_OEIS | PL011_BEIS
180 		| PL011_PEIS | PL011_FEIS);
181 
182 	// ** Disable interrupts
183 	Out32(PL011_IMSC, 0);
184 }
185 
186 
187 ArchUARTPL011::~ArchUARTPL011()
188 {
189 }
190 
191 
192 void
193 ArchUARTPL011::Out32(int reg, uint32 data)
194 {
195 	*(volatile uint32*)(Base() + reg) = data;
196 }
197 
198 
199 uint32
200 ArchUARTPL011::In32(int reg)
201 {
202 	return *(volatile uint32*)(Base() + reg);
203 }
204 
205 
206 void
207 ArchUARTPL011::Barrier()
208 {
209 	asm volatile ("" : : : "memory");
210 }
211 
212 
213 void
214 ArchUARTPL011::InitPort(uint32 baud)
215 {
216 	// Calculate baud divisor
217 	uint32 baudDivisor = Clock() / (16 * baud);
218 	uint32 remainder = Clock() % (16 * baud);
219 	uint32 baudFractional = ((8 * remainder) / baud >> 1)
220 		+ ((8 * remainder) / baud & 1);
221 
222 	// Disable UART
223 	Disable();
224 
225 	// Set baud divisor
226 	Out32(PL011_IBRD, baudDivisor);
227 	Out32(PL011_FBRD, baudFractional);
228 
229 	// Set LCR 8n1, enable fifo
230 	Out32(PL011_LCRH, PL01x_LCRH_WLEN_8 | PL01x_LCRH_FEN);
231 
232 	// Enable UART
233 	Enable();
234 }
235 
236 
237 void
238 ArchUARTPL011::InitEarly()
239 {
240 	// Perform special hardware UART configuration
241 }
242 
243 
244 void
245 ArchUARTPL011::Enable()
246 {
247 	uint32 cr = PL01x_CR_UARTEN;
248 		// Enable UART
249 	cr |= PL011_CR_TXE | PL011_CR_RXE;
250 		// Enable TX and RX
251 
252 	Out32(PL011_CR, cr);
253 
254 	DebugUART::Enable();
255 }
256 
257 
258 void
259 ArchUARTPL011::Disable()
260 {
261 	// Disable everything
262 	Out32(PL011_CR, 0);
263 
264 	DebugUART::Disable();
265 }
266 
267 
268 int
269 ArchUARTPL011::PutChar(char c)
270 {
271 	if (Enabled() == true) {
272 		// Wait until there is room in fifo
273 		while ((In32(PL01x_FR) & PL01x_FR_TXFF) != 0)
274 			Barrier();
275 
276 		Out32(PL01x_DR, c);
277 		return 0;
278 	}
279 
280 	return -1;
281 }
282 
283 
284 int
285 ArchUARTPL011::GetChar(bool wait)
286 {
287 	if (Enabled() == true) {
288 		// Wait until a character is received?
289 		if (wait) {
290 			while ((In32(PL01x_FR) & PL01x_FR_RXFE) != 0)
291 				Barrier();
292 		}
293 		return In32(PL01x_DR);
294 	}
295 
296 	return -1;
297 }
298 
299 
300 void
301 ArchUARTPL011::FlushTx()
302 {
303 	// Wait until transmit fifo empty
304 	while ((In32(PL01x_FR) & PL011_FR_TXFE) == 0)
305 		Barrier();
306 }
307 
308 
309 void
310 ArchUARTPL011::FlushRx()
311 {
312 	// Wait until receive fifo empty
313 	while ((In32(PL01x_FR) & PL01x_FR_RXFE) == 0)
314 		Barrier();
315 }
316 
317 
318 ArchUARTPL011 *arch_get_uart_pl011(addr_t base, int64 clock)
319 {
320 	static char buffer[sizeof(ArchUARTPL011)];
321 	ArchUARTPL011 *uart = new(buffer) ArchUARTPL011(base, clock);
322 	return uart;
323 }
324