xref: /openbmc/u-boot/drivers/serial/serial_sh.c (revision 730d2544)
1 /*
2  * SuperH SCIF device driver.
3  * Copyright (C) 2013  Renesas Electronics Corporation
4  * Copyright (C) 2007,2008,2010, 2014 Nobuhiro Iwamatsu
5  * Copyright (C) 2002 - 2008  Paul Mundt
6  *
7  * SPDX-License-Identifier:	GPL-2.0+
8  */
9 
10 #include <common.h>
11 #include <errno.h>
12 #include <dm.h>
13 #include <asm/io.h>
14 #include <asm/processor.h>
15 #include <serial.h>
16 #include <linux/compiler.h>
17 #include <dm/platform_data/serial_sh.h>
18 #include "serial_sh.h"
19 
20 DECLARE_GLOBAL_DATA_PTR;
21 
22 #if defined(CONFIG_CPU_SH7760) || \
23 	defined(CONFIG_CPU_SH7780) || \
24 	defined(CONFIG_CPU_SH7785) || \
25 	defined(CONFIG_CPU_SH7786)
26 static int scif_rxfill(struct uart_port *port)
27 {
28 	return sci_in(port, SCRFDR) & 0xff;
29 }
30 #elif defined(CONFIG_CPU_SH7763)
31 static int scif_rxfill(struct uart_port *port)
32 {
33 	if ((port->mapbase == 0xffe00000) ||
34 	    (port->mapbase == 0xffe08000)) {
35 		/* SCIF0/1*/
36 		return sci_in(port, SCRFDR) & 0xff;
37 	} else {
38 		/* SCIF2 */
39 		return sci_in(port, SCFDR) & SCIF2_RFDC_MASK;
40 	}
41 }
42 #elif defined(CONFIG_ARCH_SH7372)
43 static int scif_rxfill(struct uart_port *port)
44 {
45 	if (port->type == PORT_SCIFA)
46 		return sci_in(port, SCFDR) & SCIF_RFDC_MASK;
47 	else
48 		return sci_in(port, SCRFDR);
49 }
50 #else
51 static int scif_rxfill(struct uart_port *port)
52 {
53 	return sci_in(port, SCFDR) & SCIF_RFDC_MASK;
54 }
55 #endif
56 
57 static void sh_serial_init_generic(struct uart_port *port)
58 {
59 	sci_out(port, SCSCR , SCSCR_INIT(port));
60 	sci_out(port, SCSCR , SCSCR_INIT(port));
61 	sci_out(port, SCSMR, 0);
62 	sci_out(port, SCSMR, 0);
63 	sci_out(port, SCFCR, SCFCR_RFRST|SCFCR_TFRST);
64 	sci_in(port, SCFCR);
65 	sci_out(port, SCFCR, 0);
66 }
67 
68 static void
69 sh_serial_setbrg_generic(struct uart_port *port, int clk, int baudrate)
70 {
71 	if (port->clk_mode == EXT_CLK) {
72 		unsigned short dl = DL_VALUE(baudrate, clk);
73 		sci_out(port, DL, dl);
74 		/* Need wait: Clock * 1/dl * 1/16 */
75 		udelay((1000000 * dl * 16 / clk) * 1000 + 1);
76 	} else {
77 		sci_out(port, SCBRR, SCBRR_VALUE(baudrate, clk));
78 	}
79 }
80 
81 static void handle_error(struct uart_port *port)
82 {
83 	sci_in(port, SCxSR);
84 	sci_out(port, SCxSR, SCxSR_ERROR_CLEAR(port));
85 	sci_in(port, SCLSR);
86 	sci_out(port, SCLSR, 0x00);
87 }
88 
89 static int serial_raw_putc(struct uart_port *port, const char c)
90 {
91 	/* Tx fifo is empty */
92 	if (!(sci_in(port, SCxSR) & SCxSR_TEND(port)))
93 		return -EAGAIN;
94 
95 	sci_out(port, SCxTDR, c);
96 	sci_out(port, SCxSR, sci_in(port, SCxSR) & ~SCxSR_TEND(port));
97 
98 	return 0;
99 }
100 
101 static int serial_rx_fifo_level(struct uart_port *port)
102 {
103 	return scif_rxfill(port);
104 }
105 
106 static int sh_serial_tstc_generic(struct uart_port *port)
107 {
108 	if (sci_in(port, SCxSR) & SCIF_ERRORS) {
109 		handle_error(port);
110 		return 0;
111 	}
112 
113 	return serial_rx_fifo_level(port) ? 1 : 0;
114 }
115 
116 static int serial_getc_check(struct uart_port *port)
117 {
118 	unsigned short status;
119 
120 	status = sci_in(port, SCxSR);
121 
122 	if (status & SCIF_ERRORS)
123 		handle_error(port);
124 	if (sci_in(port, SCLSR) & SCxSR_ORER(port))
125 		handle_error(port);
126 	return status & (SCIF_DR | SCxSR_RDxF(port));
127 }
128 
129 static int sh_serial_getc_generic(struct uart_port *port)
130 {
131 	unsigned short status;
132 	char ch;
133 
134 	if (!serial_getc_check(port))
135 		return -EAGAIN;
136 
137 	ch = sci_in(port, SCxRDR);
138 	status = sci_in(port, SCxSR);
139 
140 	sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
141 
142 	if (status & SCIF_ERRORS)
143 		handle_error(port);
144 
145 	if (sci_in(port, SCLSR) & SCxSR_ORER(port))
146 		handle_error(port);
147 
148 	return ch;
149 }
150 
151 #ifdef CONFIG_DM_SERIAL
152 
153 static int sh_serial_pending(struct udevice *dev, bool input)
154 {
155 	struct uart_port *priv = dev_get_priv(dev);
156 
157 	return sh_serial_tstc_generic(priv);
158 }
159 
160 static int sh_serial_putc(struct udevice *dev, const char ch)
161 {
162 	struct uart_port *priv = dev_get_priv(dev);
163 
164 	return serial_raw_putc(priv, ch);
165 }
166 
167 static int sh_serial_getc(struct udevice *dev)
168 {
169 	struct uart_port *priv = dev_get_priv(dev);
170 
171 	return sh_serial_getc_generic(priv);
172 }
173 
174 static int sh_serial_setbrg(struct udevice *dev, int baudrate)
175 {
176 	struct sh_serial_platdata *plat = dev_get_platdata(dev);
177 	struct uart_port *priv = dev_get_priv(dev);
178 
179 	sh_serial_setbrg_generic(priv, plat->clk, baudrate);
180 
181 	return 0;
182 }
183 
184 static int sh_serial_probe(struct udevice *dev)
185 {
186 	struct sh_serial_platdata *plat = dev_get_platdata(dev);
187 	struct uart_port *priv = dev_get_priv(dev);
188 
189 	priv->membase	= (unsigned char *)plat->base;
190 	priv->mapbase	= plat->base;
191 	priv->type	= plat->type;
192 	priv->clk_mode	= plat->clk_mode;
193 
194 	sh_serial_init_generic(priv);
195 
196 	return 0;
197 }
198 
199 static const struct dm_serial_ops sh_serial_ops = {
200 	.putc = sh_serial_putc,
201 	.pending = sh_serial_pending,
202 	.getc = sh_serial_getc,
203 	.setbrg = sh_serial_setbrg,
204 };
205 
206 #ifdef CONFIG_OF_CONTROL
207 static const struct udevice_id sh_serial_id[] ={
208 	{.compatible = "renesas,sci", .data = PORT_SCI},
209 	{.compatible = "renesas,scif", .data = PORT_SCIF},
210 	{.compatible = "renesas,scifa", .data = PORT_SCIFA},
211 	{}
212 };
213 
214 static int sh_serial_ofdata_to_platdata(struct udevice *dev)
215 {
216 	struct sh_serial_platdata *plat = dev_get_platdata(dev);
217 	fdt_addr_t addr;
218 
219 	addr = fdtdec_get_addr(gd->fdt_blob, dev->of_offset, "reg");
220 	if (addr == FDT_ADDR_T_NONE)
221 		return -EINVAL;
222 
223 	plat->base = addr;
224 	plat->clk = fdtdec_get_int(gd->fdt_blob, dev->of_offset, "clock", 1);
225 	plat->type = dev_get_driver_data(dev);
226 	return 0;
227 }
228 #endif
229 
230 U_BOOT_DRIVER(serial_sh) = {
231 	.name	= "serial_sh",
232 	.id	= UCLASS_SERIAL,
233 	.of_match = of_match_ptr(sh_serial_id),
234 	.ofdata_to_platdata = of_match_ptr(sh_serial_ofdata_to_platdata),
235 	.platdata_auto_alloc_size = sizeof(struct sh_serial_platdata),
236 	.probe	= sh_serial_probe,
237 	.ops	= &sh_serial_ops,
238 	.flags	= DM_FLAG_PRE_RELOC,
239 	.priv_auto_alloc_size = sizeof(struct uart_port),
240 };
241 
242 #else /* CONFIG_DM_SERIAL */
243 
244 #if defined(CONFIG_CONS_SCIF0)
245 # define SCIF_BASE	SCIF0_BASE
246 #elif defined(CONFIG_CONS_SCIF1)
247 # define SCIF_BASE	SCIF1_BASE
248 #elif defined(CONFIG_CONS_SCIF2)
249 # define SCIF_BASE	SCIF2_BASE
250 #elif defined(CONFIG_CONS_SCIF3)
251 # define SCIF_BASE	SCIF3_BASE
252 #elif defined(CONFIG_CONS_SCIF4)
253 # define SCIF_BASE	SCIF4_BASE
254 #elif defined(CONFIG_CONS_SCIF5)
255 # define SCIF_BASE	SCIF5_BASE
256 #elif defined(CONFIG_CONS_SCIF6)
257 # define SCIF_BASE	SCIF6_BASE
258 #elif defined(CONFIG_CONS_SCIF7)
259 # define SCIF_BASE	SCIF7_BASE
260 #else
261 # error "Default SCIF doesn't set....."
262 #endif
263 
264 #if defined(CONFIG_SCIF_A)
265 	#define SCIF_BASE_PORT	PORT_SCIFA
266 #elif defined(CONFIG_SCI)
267 	#define SCIF_BASE_PORT  PORT_SCI
268 #else
269 	#define SCIF_BASE_PORT	PORT_SCIF
270 #endif
271 
272 static struct uart_port sh_sci = {
273 	.membase	= (unsigned char *)SCIF_BASE,
274 	.mapbase	= SCIF_BASE,
275 	.type		= SCIF_BASE_PORT,
276 #ifdef CONFIG_SCIF_USE_EXT_CLK
277 	.clk_mode =	EXT_CLK,
278 #endif
279 };
280 
281 static void sh_serial_setbrg(void)
282 {
283 	DECLARE_GLOBAL_DATA_PTR;
284 	struct uart_port *port = &sh_sci;
285 
286 	sh_serial_setbrg_generic(port, CONFIG_SH_SCIF_CLK_FREQ, gd->baudrate);
287 }
288 
289 static int sh_serial_init(void)
290 {
291 	struct uart_port *port = &sh_sci;
292 
293 	sh_serial_init_generic(port);
294 	serial_setbrg();
295 
296 	return 0;
297 }
298 
299 static void sh_serial_putc(const char c)
300 {
301 	struct uart_port *port = &sh_sci;
302 
303 	if (c == '\n') {
304 		while (1) {
305 			if  (serial_raw_putc(port, '\r') != -EAGAIN)
306 				break;
307 		}
308 	}
309 	while (1) {
310 		if  (serial_raw_putc(port, c) != -EAGAIN)
311 			break;
312 	}
313 }
314 
315 static int sh_serial_tstc(void)
316 {
317 	struct uart_port *port = &sh_sci;
318 
319 	return sh_serial_tstc_generic(port);
320 }
321 
322 static int sh_serial_getc(void)
323 {
324 	struct uart_port *port = &sh_sci;
325 	int ch;
326 
327 	while (1) {
328 		ch = sh_serial_getc_generic(port);
329 		if (ch != -EAGAIN)
330 			break;
331 	}
332 
333 	return ch;
334 }
335 
336 static struct serial_device sh_serial_drv = {
337 	.name	= "sh_serial",
338 	.start	= sh_serial_init,
339 	.stop	= NULL,
340 	.setbrg	= sh_serial_setbrg,
341 	.putc	= sh_serial_putc,
342 	.puts	= default_serial_puts,
343 	.getc	= sh_serial_getc,
344 	.tstc	= sh_serial_tstc,
345 };
346 
347 void sh_serial_initialize(void)
348 {
349 	serial_register(&sh_serial_drv);
350 }
351 
352 __weak struct serial_device *default_serial_console(void)
353 {
354 	return &sh_serial_drv;
355 }
356 #endif /* CONFIG_DM_SERIAL */
357