1 /***********************************************************************
2  *
3  * (C) Copyright 2004-2009
4  * DENX Software Engineering
5  * Wolfgang Denk, wd@denx.de
6  *
7  * Simple 16550A serial driver
8  *
9  * Originally from linux source (drivers/char/ps2ser.c)
10  *
11  * Used by the PS/2 multiplexer driver (ps2mult.c)
12  *
13  ***********************************************************************/
14 
15 #include <common.h>
16 
17 #include <asm/io.h>
18 #include <asm/atomic.h>
19 #include <ps2mult.h>
20 /* This is needed for ns16550.h */
21 #ifndef CONFIG_SYS_NS16550_REG_SIZE
22 #define CONFIG_SYS_NS16550_REG_SIZE 1
23 #endif
24 #include <ns16550.h>
25 
26 DECLARE_GLOBAL_DATA_PTR;
27 
28 /* #define	DEBUG */
29 
30 #define PS2SER_BAUD	57600
31 
32 #ifdef CONFIG_MPC5xxx
33 #if CONFIG_PS2SERIAL == 1
34 #define PSC_BASE MPC5XXX_PSC1
35 #elif CONFIG_PS2SERIAL == 2
36 #define PSC_BASE MPC5XXX_PSC2
37 #elif CONFIG_PS2SERIAL == 3
38 #define PSC_BASE MPC5XXX_PSC3
39 #elif CONFIG_PS2SERIAL == 4
40 #define PSC_BASE MPC5XXX_PSC4
41 #elif CONFIG_PS2SERIAL == 5
42 #define PSC_BASE MPC5XXX_PSC5
43 #elif CONFIG_PS2SERIAL == 6
44 #define PSC_BASE MPC5XXX_PSC6
45 #else
46 #error CONFIG_PS2SERIAL must be in 1 ... 6
47 #endif
48 
49 #elif defined(CONFIG_MPC8540) || defined(CONFIG_MPC8541) || \
50       defined(CONFIG_MPC8548) || defined(CONFIG_MPC8555)
51 
52 #if CONFIG_PS2SERIAL == 1
53 #define COM_BASE (CONFIG_SYS_CCSRBAR+0x4500)
54 #elif CONFIG_PS2SERIAL == 2
55 #define COM_BASE (CONFIG_SYS_CCSRBAR+0x4600)
56 #else
57 #error CONFIG_PS2SERIAL must be in 1 ... 2
58 #endif
59 
60 #endif /* CONFIG_MPC5xxx / CONFIG_MPC8540 / other */
61 
62 static int	ps2ser_getc_hw(void);
63 static void	ps2ser_interrupt(void *dev_id);
64 
65 extern struct	serial_state rs_table[]; /* in serial.c */
66 #if !defined(CONFIG_MPC5xxx) && !defined(CONFIG_MPC8540) && \
67     !defined(CONFIG_MPC8541) && !defined(CONFIG_MPC8548) && \
68     !defined(CONFIG_MPC8555)
69 static struct	serial_state *state;
70 #endif
71 
72 static u_char	ps2buf[PS2BUF_SIZE];
73 static atomic_t	ps2buf_cnt;
74 static int	ps2buf_in_idx;
75 static int	ps2buf_out_idx;
76 
77 #ifdef CONFIG_MPC5xxx
ps2ser_init(void)78 int ps2ser_init(void)
79 {
80 	volatile struct mpc5xxx_psc *psc = (struct mpc5xxx_psc *)PSC_BASE;
81 	unsigned long baseclk;
82 	int div;
83 
84 	/* reset PSC */
85 	psc->command = PSC_SEL_MODE_REG_1;
86 
87 	/* select clock sources */
88 	psc->psc_clock_select = 0;
89 	baseclk = (gd->ipb_clk + 16) / 32;
90 
91 	/* switch to UART mode */
92 	psc->sicr = 0;
93 
94 	/* configure parity, bit length and so on */
95 	psc->mode = PSC_MODE_8_BITS | PSC_MODE_PARNONE;
96 	psc->mode = PSC_MODE_ONE_STOP;
97 
98 	/* set up UART divisor */
99 	div = (baseclk + (PS2SER_BAUD/2)) / PS2SER_BAUD;
100 	psc->ctur = (div >> 8) & 0xff;
101 	psc->ctlr = div & 0xff;
102 
103 	/* disable all interrupts */
104 	psc->psc_imr = 0;
105 
106 	/* reset and enable Rx/Tx */
107 	psc->command = PSC_RST_RX;
108 	psc->command = PSC_RST_TX;
109 	psc->command = PSC_RX_ENABLE | PSC_TX_ENABLE;
110 
111 	return (0);
112 }
113 
114 #elif defined(CONFIG_MPC8540) || defined(CONFIG_MPC8541) || \
115       defined(CONFIG_MPC8548) || defined(CONFIG_MPC8555)
ps2ser_init(void)116 int ps2ser_init(void)
117 {
118 	NS16550_t com_port = (NS16550_t)COM_BASE;
119 
120 	com_port->ier = 0x00;
121 	com_port->lcr = UART_LCR_BKSE | UART_LCR_8N1;
122 	com_port->dll = (CONFIG_SYS_NS16550_CLK / 16 / PS2SER_BAUD) & 0xff;
123 	com_port->dlm = ((CONFIG_SYS_NS16550_CLK / 16 / PS2SER_BAUD) >> 8) & 0xff;
124 	com_port->lcr = UART_LCR_8N1;
125 	com_port->mcr = (UART_MCR_DTR | UART_MCR_RTS);
126 	com_port->fcr = (UART_FCR_FIFO_EN | UART_FCR_RXSR | UART_FCR_TXSR);
127 
128 	return (0);
129 }
130 
131 #else /* !CONFIG_MPC5xxx && !CONFIG_MPC8540 / other */
132 
ps2ser_in(int offset)133 static inline unsigned int ps2ser_in(int offset)
134 {
135 	return readb((unsigned long) state->iomem_base + offset);
136 }
137 
ps2ser_out(int offset,int value)138 static inline void ps2ser_out(int offset, int value)
139 {
140 	writeb(value, (unsigned long) state->iomem_base + offset);
141 }
142 
ps2ser_init(void)143 int ps2ser_init(void)
144 {
145 	int quot;
146 	unsigned cval;
147 
148 	state = rs_table + CONFIG_PS2SERIAL;
149 
150 	quot = state->baud_base / PS2SER_BAUD;
151 	cval = 0x3; /* 8N1 - 8 data bits, no parity bits, 1 stop bit */
152 
153 	  /* Set speed, enable interrupts, enable FIFO
154 	   */
155 	ps2ser_out(UART_LCR, cval | UART_LCR_DLAB);
156 	ps2ser_out(UART_DLL, quot & 0xff);
157 	ps2ser_out(UART_DLM, quot >> 8);
158 	ps2ser_out(UART_LCR, cval);
159 	ps2ser_out(UART_IER, UART_IER_RDI);
160 	ps2ser_out(UART_MCR, UART_MCR_OUT2 | UART_MCR_DTR | UART_MCR_RTS);
161 	ps2ser_out(UART_FCR,
162 	    UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
163 
164 	/* If we read 0xff from the LSR, there is no UART here
165 	 */
166 	if (ps2ser_in(UART_LSR) == 0xff) {
167 		printf ("ps2ser.c: no UART found\n");
168 		return -1;
169 	}
170 
171 	irq_install_handler(state->irq, ps2ser_interrupt, NULL);
172 
173 	return 0;
174 }
175 #endif /* CONFIG_MPC5xxx / CONFIG_MPC8540 / other */
176 
ps2ser_putc(int chr)177 void ps2ser_putc(int chr)
178 {
179 #ifdef CONFIG_MPC5xxx
180 	volatile struct mpc5xxx_psc *psc = (struct mpc5xxx_psc *)PSC_BASE;
181 #elif defined(CONFIG_MPC8540) || defined(CONFIG_MPC8541) || \
182       defined(CONFIG_MPC8548) || defined(CONFIG_MPC8555)
183 	NS16550_t com_port = (NS16550_t)COM_BASE;
184 #endif
185 #ifdef DEBUG
186 	printf(">>>> 0x%02x\n", chr);
187 #endif
188 
189 #ifdef CONFIG_MPC5xxx
190 	while (!(psc->psc_status & PSC_SR_TXRDY));
191 
192 	psc->psc_buffer_8 = chr;
193 #elif defined(CONFIG_MPC8540) || defined(CONFIG_MPC8541) || \
194       defined(CONFIG_MPC8548) || defined(CONFIG_MPC8555)
195 	while ((com_port->lsr & UART_LSR_THRE) == 0);
196 	com_port->thr = chr;
197 #else
198 	while (!(ps2ser_in(UART_LSR) & UART_LSR_THRE));
199 
200 	ps2ser_out(UART_TX, chr);
201 #endif
202 }
203 
ps2ser_getc_hw(void)204 static int ps2ser_getc_hw(void)
205 {
206 #ifdef CONFIG_MPC5xxx
207 	volatile struct mpc5xxx_psc *psc = (struct mpc5xxx_psc *)PSC_BASE;
208 #elif defined(CONFIG_MPC8540) || defined(CONFIG_MPC8541) || \
209       defined(CONFIG_MPC8548) || defined(CONFIG_MPC8555)
210 	NS16550_t com_port = (NS16550_t)COM_BASE;
211 #endif
212 	int res = -1;
213 
214 #ifdef CONFIG_MPC5xxx
215 	if (psc->psc_status & PSC_SR_RXRDY) {
216 		res = (psc->psc_buffer_8);
217 	}
218 #elif defined(CONFIG_MPC8540) || defined(CONFIG_MPC8541) || \
219       defined(CONFIG_MPC8548) || defined(CONFIG_MPC8555)
220 	if (com_port->lsr & UART_LSR_DR) {
221 		res = com_port->rbr;
222 	}
223 #else
224 	if (ps2ser_in(UART_LSR) & UART_LSR_DR) {
225 		res = (ps2ser_in(UART_RX));
226 	}
227 #endif
228 
229 	return res;
230 }
231 
ps2ser_getc(void)232 int ps2ser_getc(void)
233 {
234 	volatile int chr;
235 	int flags;
236 
237 #ifdef DEBUG
238 	printf("<< ");
239 #endif
240 
241 	flags = disable_interrupts();
242 
243 	do {
244 		if (atomic_read(&ps2buf_cnt) != 0) {
245 			chr = ps2buf[ps2buf_out_idx++];
246 			ps2buf_out_idx &= (PS2BUF_SIZE - 1);
247 			atomic_dec(&ps2buf_cnt);
248 		} else {
249 			chr = ps2ser_getc_hw();
250 		}
251 	}
252 	while (chr < 0);
253 
254 	if (flags) enable_interrupts();
255 
256 #ifdef DEBUG
257 	printf("0x%02x\n", chr);
258 #endif
259 
260 	return chr;
261 }
262 
ps2ser_check(void)263 int ps2ser_check(void)
264 {
265 	int flags;
266 
267 	flags = disable_interrupts();
268 	ps2ser_interrupt(NULL);
269 	if (flags) enable_interrupts();
270 
271 	return atomic_read(&ps2buf_cnt);
272 }
273 
ps2ser_interrupt(void * dev_id)274 static void ps2ser_interrupt(void *dev_id)
275 {
276 #ifdef CONFIG_MPC5xxx
277 	volatile struct mpc5xxx_psc *psc = (struct mpc5xxx_psc *)PSC_BASE;
278 #elif defined(CONFIG_MPC8540) || defined(CONFIG_MPC8541) || \
279       defined(CONFIG_MPC8548) || defined(CONFIG_MPC8555)
280 	NS16550_t com_port = (NS16550_t)COM_BASE;
281 #endif
282 	int chr;
283 	int status;
284 
285 	do {
286 		chr = ps2ser_getc_hw();
287 #ifdef CONFIG_MPC5xxx
288 		status = psc->psc_status;
289 #elif defined(CONFIG_MPC8540) || defined(CONFIG_MPC8541) || \
290       defined(CONFIG_MPC8548) || defined(CONFIG_MPC8555)
291 		status = com_port->lsr;
292 #else
293 		status = ps2ser_in(UART_IIR);
294 #endif
295 		if (chr < 0) continue;
296 
297 		if (atomic_read(&ps2buf_cnt) < PS2BUF_SIZE) {
298 			ps2buf[ps2buf_in_idx++] = chr;
299 			ps2buf_in_idx &= (PS2BUF_SIZE - 1);
300 			atomic_inc(&ps2buf_cnt);
301 		} else {
302 			printf ("ps2ser.c: buffer overflow\n");
303 		}
304 #ifdef CONFIG_MPC5xxx
305 	} while (status & PSC_SR_RXRDY);
306 #elif defined(CONFIG_MPC8540) || defined(CONFIG_MPC8541) || \
307       defined(CONFIG_MPC8548) || defined(CONFIG_MPC8555)
308 	} while (status & UART_LSR_DR);
309 #else
310 	} while (status & UART_IIR_RDI);
311 #endif
312 
313 	if (atomic_read(&ps2buf_cnt)) {
314 		ps2mult_callback(atomic_read(&ps2buf_cnt));
315 	}
316 }
317