xref: /haiku/src/system/kernel/arch/arm/arch_uart_pl011.cpp (revision 6889394848e2dc9f41ff53b12141d572822ca0c6)
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 <new>
15 
16 
17 #define PL01x_DR	0x00 // Data read or written
18 #define PL01x_RSR	0x04 // Receive status, read
19 #define PL01x_ECR	0x04 // Error clear, write
20 #define PL010_LCRH	0x08 // Line control, high
21 #define PL010_LCRM	0x0C // Line control, middle
22 #define PL010_LCRL	0x10 // Line control, low
23 #define PL010_CR	0x14 // Control
24 #define PL01x_FR	0x18 // Flag (r/o)
25 #define PL010_IIR	0x1C // Interrupt ID (r)
26 #define PL010_ICR	0x1C // Interrupt clear (w)
27 #define PL01x_ILPR	0x20 // IrDA low power
28 #define PL011_IBRD	0x24 // Interrupt baud rate divisor
29 #define PL011_FBRD	0x28 // Fractional baud rate divisor
30 #define PL011_LCRH	0x2C // Line control
31 #define PL011_CR	0x30 // Control
32 #define PL011_IFLS	0x34 // Interrupt fifo level
33 #define PL011_IMSC	0x38 // Interrupt mask
34 #define PL011_RIS	0x3C // Raw interrupt
35 #define PL011_MIS	0x40 // Masked interrupt
36 #define PL011_ICR	0x44 // Interrupt clear
37 #define PL011_DMACR	0x48 // DMA control register
38 
39 #define PL011_DR_OE		(1 << 11)
40 #define PL011_DR_BE		(1 << 10)
41 #define PL011_DR_PE		(1 << 9)
42 #define PL011_DR_FE		(1 << 8)
43 
44 #define PL01x_RSR_OE	0x08
45 #define PL01x_RSR_BE	0x04
46 #define PL01x_RSR_PE	0x02
47 #define PL01x_RSR_FE	0x01
48 
49 #define PL011_FR_RI		0x100
50 #define PL011_FR_TXFE	0x080
51 #define PL011_FR_RXFF	0x040
52 #define PL01x_FR_TXFF	0x020
53 #define PL01x_FR_RXFE	0x010
54 #define PL01x_FR_BUSY	0x008
55 #define PL01x_FR_DCD	0x004
56 #define PL01x_FR_DSR	0x002
57 #define PL01x_FR_CTS	0x001
58 #define PL01x_FR_TMSK	(PL01x_FR_TXFF | PL01x_FR_BUSY)
59 
60 #define PL011_CR_CTSEN	0x8000 // CTS flow control
61 #define PL011_CR_RTSEN	0x4000 // RTS flow control
62 #define PL011_CR_OUT2	0x2000 // OUT2
63 #define PL011_CR_OUT1	0x1000 // OUT1
64 #define PL011_CR_RTS	0x0800 // RTS
65 #define PL011_CR_DTR	0x0400 // DTR
66 #define PL011_CR_RXE	0x0200 // Receive enable
67 #define PL011_CR_TXE	0x0100 // Transmit enable
68 #define PL011_CR_LBE	0x0080 // Loopback enable
69 #define PL010_CR_RTIE	0x0040
70 #define PL010_CR_TIE	0x0020
71 #define PL010_CR_RIE	0x0010
72 #define PL010_CR_MSIE	0x0008
73 #define PL01x_CR_IIRLP	0x0004 // SIR low power mode
74 #define PL01x_CR_SIREN	0x0002 // SIR enable
75 #define PL01x_CR_UARTEN 0x0001 // UART enable
76 
77 #define PL011_LCRH_SPS		0x80
78 #define PL01x_LCRH_WLEN_8	0x60
79 #define PL01x_LCRH_WLEN_7	0x40
80 #define PL01x_LCRH_WLEN_6	0x20
81 #define PL01x_LCRH_WLEN_5	0x00
82 #define PL01x_LCRH_FEN		0x10
83 #define PL01x_LCRH_STP2		0x08
84 #define PL01x_LCRH_EPS		0x04
85 #define PL01x_LCRH_PEN		0x02
86 #define PL01x_LCRH_BRK		0x01
87 
88 #define PL010_IIR_RTIS	0x08
89 #define PL010_IIR_TIS	0x04
90 #define PL010_IIR_RIS	0x02
91 #define PL010_IIR_MIS	0x01
92 
93 #define PL011_IFLS_RX1_8	(0 << 3)
94 #define PL011_IFLS_RX2_8	(1 << 3)
95 #define PL011_IFLS_RX4_8	(2 << 3)
96 #define PL011_IFLS_RX6_8	(3 << 3)
97 #define PL011_IFLS_RX7_8	(4 << 3)
98 #define PL011_IFLS_TX1_8	(0 << 0)
99 #define PL011_IFLS_TX2_8	(1 << 0)
100 #define PL011_IFLS_TX4_8	(2 << 0)
101 #define PL011_IFLS_TX6_8	(3 << 0)
102 #define PL011_IFLS_TX7_8	(4 << 0)
103 
104 #define PL011_IFLS_RX_HALF	(5 << 3) // ST vendor only
105 #define PL011_IFLS_TX_HALF	(5 << 0) // ST vendor only
106 
107 #define PL011_OEIM		(1 << 10) // overrun error interrupt mask
108 #define PL011_BEIM		(1 << 9) // break error interrupt mask
109 #define PL011_PEIM		(1 << 8) // parity error interrupt mask
110 #define PL011_FEIM		(1 << 7) // framing error interrupt mask
111 #define PL011_RTIM		(1 << 6) // receive timeout interrupt mask
112 #define PL011_TXIM		(1 << 5) // transmit interrupt mask
113 #define PL011_RXIM		(1 << 4) // receive interrupt mask
114 #define PL011_DSRMIM	(1 << 3) // DSR interrupt mask
115 #define PL011_DCDMIM	(1 << 2) // DCD interrupt mask
116 #define PL011_CTSMIM	(1 << 1) // CTS interrupt mask
117 #define PL011_RIMIM		(1 << 0) // RI interrupt mask
118 
119 #define PL011_OEIS		(1 << 10) // overrun error interrupt state
120 #define PL011_BEIS		(1 << 9) // break error interrupt state
121 #define PL011_PEIS		(1 << 8) // parity error interrupt state
122 #define PL011_FEIS		(1 << 7) // framing error interrupt	state
123 #define PL011_RTIS		(1 << 6) // receive timeout interrupt state
124 #define PL011_TXIS		(1 << 5) // transmit interrupt state
125 #define PL011_RXIS		(1 << 4) // receive interrupt state
126 #define PL011_DSRMIS	(1 << 3) // DSR interrupt state
127 #define PL011_DCDMIS	(1 << 2) // DCD interrupt state
128 #define PL011_CTSMIS	(1 << 1) // CTS interrupt state
129 #define PL011_RIMIS		(1 << 0) // RI interrupt state
130 
131 #define PL011_OEIC		(1 << 10) // overrun error interrupt clear
132 #define PL011_BEIC		(1 << 9) // break error interrupt clear
133 #define PL011_PEIC		(1 << 8) // parity error interrupt clear
134 #define PL011_FEIC		(1 << 7) // framing error interrupt clear
135 #define PL011_RTIC		(1 << 6) // receive timeout interrupt clear
136 #define PL011_TXIC		(1 << 5) // transmit interrupt clear
137 #define PL011_RXIC		(1 << 4) // receive interrupt clear
138 #define PL011_DSRMIC	(1 << 3) // DSR interrupt clear
139 #define PL011_DCDMIC	(1 << 2) // DCD interrupt clear
140 #define PL011_CTSMIC	(1 << 1) // CTS interrupt clear
141 #define PL011_RIMIC		(1 << 0) // RI interrupt clear
142 
143 #define PL011_DMAONERR	(1 << 2) // disable dma on err
144 #define PL011_TXDMAE	(1 << 1) // enable transmit dma
145 #define PL011_RXDMAE	(1 << 0) // enable receive dma
146 
147 
148 ArchUARTPL011::ArchUARTPL011(addr_t base, int64 clock)
149 	:
150 	DebugUART(base, clock)
151 {
152 	Barrier();
153 
154 	// ** Loopback test
155 	uint32 cr = PL01x_CR_UARTEN;
156 		// Enable UART
157 	cr |= PL011_CR_TXE;
158 		// Enable TX
159 	cr |= PL011_CR_LBE;
160 		// Enable Loopback mode
161 	Out32(PL011_CR, cr);
162 
163 	Out32(PL011_FBRD, 0);
164 	Out32(PL011_IBRD, 1);
165 	Out32(PL011_LCRH, 0); // TODO: ST is different tx, rx lcr
166 
167 	// Write a 0 to the port and wait for confim..
168 	Out32(PL01x_DR, 0);
169 
170 	while (In32(PL01x_FR) & PL01x_FR_BUSY)
171 		Barrier();
172 
173 	// ** Disable loopback, enable uart
174 	cr = PL01x_CR_UARTEN | PL011_CR_RXE | PL011_CR_TXE;
175 	Out32(PL011_CR, cr);
176 
177 	// ** Clear interrupts
178 	Out32(PL011_ICR, PL011_OEIS | PL011_BEIS
179 		| PL011_PEIS | PL011_FEIS);
180 
181 	// ** Disable interrupts
182 	Out32(PL011_IMSC, 0);
183 }
184 
185 
186 ArchUARTPL011::~ArchUARTPL011()
187 {
188 }
189 
190 
191 void
192 ArchUARTPL011::Out32(int reg, uint32 data)
193 {
194 	*(volatile uint32*)(Base() + reg) = data;
195 }
196 
197 
198 uint32
199 ArchUARTPL011::In32(int reg)
200 {
201 	return *(volatile uint32*)(Base() + reg);
202 }
203 
204 
205 void
206 ArchUARTPL011::Barrier()
207 {
208 	asm volatile ("" : : : "memory");
209 }
210 
211 
212 void
213 ArchUARTPL011::InitPort(uint32 baud)
214 {
215 	// Calculate baud divisor
216 	uint32 baudDivisor = Clock() / (16 * baud);
217 	uint32 remainder = Clock() % (16 * baud);
218 	uint32 baudFractional = ((8 * remainder) / baud >> 1)
219 		+ ((8 * remainder) / baud & 1);
220 
221 	// Disable UART
222 	Disable();
223 
224 	// Set baud divisor
225 	Out32(PL011_IBRD, baudDivisor);
226 	Out32(PL011_FBRD, baudFractional);
227 
228 	// Set LCR 8n1, enable fifo
229 	Out32(PL011_LCRH, PL01x_LCRH_WLEN_8 | PL01x_LCRH_FEN);
230 
231 	// Enable UART
232 	Enable();
233 }
234 
235 
236 void
237 ArchUARTPL011::InitEarly()
238 {
239 	// Perform special hardware UART configuration
240 }
241 
242 
243 void
244 ArchUARTPL011::Enable()
245 {
246 	uint32 cr = PL01x_CR_UARTEN;
247 		// Enable UART
248 	cr |= PL011_CR_TXE | PL011_CR_RXE;
249 		// Enable TX and RX
250 
251 	Out32(PL011_CR, cr);
252 
253 	DebugUART::Enable();
254 }
255 
256 
257 void
258 ArchUARTPL011::Disable()
259 {
260 	// Disable everything
261 	Out32(PL011_CR, 0);
262 
263 	DebugUART::Disable();
264 }
265 
266 
267 int
268 ArchUARTPL011::PutChar(char c)
269 {
270 	if (Enabled() == true) {
271 		// Wait until there is room in fifo
272 		while ((In32(PL01x_FR) & PL01x_FR_TXFF) != 0)
273 			Barrier();
274 
275 		Out32(PL01x_DR, c);
276 		return 0;
277 	}
278 
279 	return -1;
280 }
281 
282 
283 int
284 ArchUARTPL011::GetChar(bool wait)
285 {
286 	if (Enabled() == true) {
287 		// Wait until a character is received?
288 		if (wait) {
289 			while ((In32(PL01x_FR) & PL01x_FR_RXFE) != 0)
290 				Barrier();
291 		}
292 		return In32(PL01x_DR);
293 	}
294 
295 	return -1;
296 }
297 
298 
299 void
300 ArchUARTPL011::FlushTx()
301 {
302 	// Wait until transmit fifo empty
303 	while ((In32(PL01x_FR) & PL011_FR_TXFE) == 0)
304 		Barrier();
305 }
306 
307 
308 void
309 ArchUARTPL011::FlushRx()
310 {
311 	// Wait until receive fifo empty
312 	while ((In32(PL01x_FR) & PL01x_FR_RXFE) == 0)
313 		Barrier();
314 }
315 
316 
317 ArchUARTPL011 *arch_get_uart_pl011(addr_t base, int64 clock)
318 {
319 	static char buffer[sizeof(ArchUARTPL011)];
320 	ArchUARTPL011 *uart = new(buffer) ArchUARTPL011(base, clock);
321 	return uart;
322 }
323