summaryrefslogtreecommitdiff
path: root/arch/ppc/cpu/mpc85xx/serial_scc.c
blob: 2dab2124fcc376c8eb4c23e4e4741e303aa49ee6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
/*
 * (C) Copyright 2003 Motorola Inc.
 * Xianghua Xiao (X.Xiao@motorola.com)
 * Modified based on 8260 for 8560.
 *
 * (C) Copyright 2000
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * See file CREDITS for list of people who contributed to this
 * project.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 *
 * Hacked for MPC8260 by Murray.Jensen@cmst.csiro.au, 19-Oct-00.
 */

/*
 * Minimal serial functions needed to use one of the SCC ports
 * as serial console interface.
 */

#include <common.h>
#include <asm/cpm_85xx.h>

DECLARE_GLOBAL_DATA_PTR;

#if defined(CONFIG_CONS_ON_SCC)

#if CONFIG_CONS_INDEX == 1	/* Console on SCC1 */

#define SCC_INDEX		0
#define PROFF_SCC		PROFF_SCC1
#define CMXSCR_MASK		(CMXSCR_GR1|CMXSCR_SC1|\
					CMXSCR_RS1CS_MSK|CMXSCR_TS1CS_MSK)
#define CMXSCR_VALUE		(CMXSCR_RS1CS_BRG1|CMXSCR_TS1CS_BRG1)
#define CPM_CR_SCC_PAGE		CPM_CR_SCC1_PAGE
#define CPM_CR_SCC_SBLOCK	CPM_CR_SCC1_SBLOCK

#elif CONFIG_CONS_INDEX == 2	/* Console on SCC2 */

#define SCC_INDEX		1
#define PROFF_SCC		PROFF_SCC2
#define CMXSCR_MASK		(CMXSCR_GR2|CMXSCR_SC2|\
					CMXSCR_RS2CS_MSK|CMXSCR_TS2CS_MSK)
#define CMXSCR_VALUE		(CMXSCR_RS2CS_BRG2|CMXSCR_TS2CS_BRG2)
#define CPM_CR_SCC_PAGE		CPM_CR_SCC2_PAGE
#define CPM_CR_SCC_SBLOCK	CPM_CR_SCC2_SBLOCK

#elif CONFIG_CONS_INDEX == 3	/* Console on SCC3 */

#define SCC_INDEX		2
#define PROFF_SCC		PROFF_SCC3
#define CMXSCR_MASK		(CMXSCR_GR3|CMXSCR_SC3|\
					CMXSCR_RS3CS_MSK|CMXSCR_TS3CS_MSK)
#define CMXSCR_VALUE		(CMXSCR_RS3CS_BRG3|CMXSCR_TS3CS_BRG3)
#define CPM_CR_SCC_PAGE		CPM_CR_SCC3_PAGE
#define CPM_CR_SCC_SBLOCK	CPM_CR_SCC3_SBLOCK

#elif CONFIG_CONS_INDEX == 4	/* Console on SCC4 */

#define SCC_INDEX		3
#define PROFF_SCC		PROFF_SCC4
#define CMXSCR_MASK		(CMXSCR_GR4|CMXSCR_SC4|\
					CMXSCR_RS4CS_MSK|CMXSCR_TS4CS_MSK)
#define CMXSCR_VALUE		(CMXSCR_RS4CS_BRG4|CMXSCR_TS4CS_BRG4)
#define CPM_CR_SCC_PAGE		CPM_CR_SCC4_PAGE
#define CPM_CR_SCC_SBLOCK	CPM_CR_SCC4_SBLOCK

#else

#error "console not correctly defined"

#endif

int serial_init (void)
{
	volatile ccsr_cpm_t *cpm = (ccsr_cpm_t *)CONFIG_SYS_MPC85xx_CPM_ADDR;
	volatile ccsr_cpm_scc_t *sp;
	volatile scc_uart_t *up;
	volatile cbd_t *tbdf, *rbdf;
	volatile ccsr_cpm_cp_t *cp = &(cpm->im_cpm_cp);
	uint	dpaddr;

	/* initialize pointers to SCC */

	sp = (ccsr_cpm_scc_t *) &(cpm->im_cpm_scc[SCC_INDEX]);
	up = (scc_uart_t *)&(cpm->im_dprambase[PROFF_SCC]);

	/* Disable transmitter/receiver.
	*/
	sp->gsmrl &= ~(SCC_GSMRL_ENR | SCC_GSMRL_ENT);

	/* put the SCC channel into NMSI (non multiplexd serial interface)
	 * mode and wire the selected SCC Tx and Rx clocks to BRGx (15-15).
	 */
	cpm->im_cpm_mux.cmxscr = \
		(cpm->im_cpm_mux.cmxscr&~CMXSCR_MASK)|CMXSCR_VALUE;

	/* Set up the baud rate generator.
	*/
	serial_setbrg ();

	/* Allocate space for two buffer descriptors in the DP ram.
	 * damm: allocating space after the two buffers for rx/tx data
	 */

	dpaddr = m8560_cpm_dpalloc((2 * sizeof (cbd_t)) + 2, 16);

	/* Set the physical address of the host memory buffers in
	 * the buffer descriptors.
	 */
	rbdf = (cbd_t *)&(cpm->im_dprambase[dpaddr]);
	rbdf->cbd_bufaddr = (uint) (rbdf+2);
	rbdf->cbd_sc = BD_SC_EMPTY | BD_SC_WRAP;
	tbdf = rbdf + 1;
	tbdf->cbd_bufaddr = ((uint) (rbdf+2)) + 1;
	tbdf->cbd_sc = BD_SC_WRAP;

	/* Set up the uart parameters in the parameter ram.
	*/
	up->scc_genscc.scc_rbase = dpaddr;
	up->scc_genscc.scc_tbase = dpaddr+sizeof(cbd_t);
	up->scc_genscc.scc_rfcr = CPMFCR_EB;
	up->scc_genscc.scc_tfcr = CPMFCR_EB;
	up->scc_genscc.scc_mrblr = 1;
	up->scc_maxidl = 0;
	up->scc_brkcr = 1;
	up->scc_parec = 0;
	up->scc_frmec = 0;
	up->scc_nosec = 0;
	up->scc_brkec = 0;
	up->scc_uaddr1 = 0;
	up->scc_uaddr2 = 0;
	up->scc_toseq = 0;
	up->scc_char1 = up->scc_char2 = up->scc_char3 = up->scc_char4 = 0x8000;
	up->scc_char5 = up->scc_char6 = up->scc_char7 = up->scc_char8 = 0x8000;
	up->scc_rccm = 0xc0ff;

	/* Mask all interrupts and remove anything pending.
	*/
	sp->sccm = 0;
	sp->scce = 0xffff;

	/* Set 8 bit FIFO, 16 bit oversampling and UART mode.
	*/
	sp->gsmrh = SCC_GSMRH_RFW;	/* 8 bit FIFO */
	sp->gsmrl = \
		SCC_GSMRL_TDCR_16 | SCC_GSMRL_RDCR_16 | SCC_GSMRL_MODE_UART;

	/* Set CTS no flow control, 1 stop bit, 8 bit character length,
	 * normal async UART mode, no parity
	 */
	sp->psmr = SCU_PSMR_CL;

	/* execute the "Init Rx and Tx params" CP command.
	*/

	while (cp->cpcr & CPM_CR_FLG)  /* wait if cp is busy */
	  ;

	cp->cpcr = mk_cr_cmd(CPM_CR_SCC_PAGE, CPM_CR_SCC_SBLOCK,
					0, CPM_CR_INIT_TRX) | CPM_CR_FLG;

	while (cp->cpcr & CPM_CR_FLG)  /* wait if cp is busy */
	  ;

	/* Enable transmitter/receiver.
	*/
	sp->gsmrl |= SCC_GSMRL_ENR | SCC_GSMRL_ENT;

	return (0);
}

void
serial_setbrg (void)
{
#if defined(CONFIG_CONS_USE_EXTC)
	m8560_cpm_extcbrg(SCC_INDEX, gd->baudrate,
		CONFIG_CONS_EXTC_RATE, CONFIG_CONS_EXTC_PINSEL);
#else
	m8560_cpm_setbrg(SCC_INDEX, gd->baudrate);
#endif
}

void
serial_putc(const char c)
{
	volatile scc_uart_t	*up;
	volatile cbd_t		*tbdf;
	volatile ccsr_cpm_t	*cpm = (ccsr_cpm_t *)CONFIG_SYS_MPC85xx_CPM_ADDR;

	if (c == '\n')
		serial_putc ('\r');

	up = (scc_uart_t *)&(cpm->im_dprambase[PROFF_SCC]);
	tbdf = (cbd_t *)&(cpm->im_dprambase[up->scc_genscc.scc_tbase]);

	/* Wait for last character to go.
	 */
	while (tbdf->cbd_sc & BD_SC_READY)
		;

	/* Load the character into the transmit buffer.
	 */
	*(volatile char *)tbdf->cbd_bufaddr = c;
	tbdf->cbd_datlen = 1;
	tbdf->cbd_sc |= BD_SC_READY;
}

void
serial_puts (const char *s)
{
	while (*s) {
		serial_putc (*s++);
	}
}

int
serial_getc(void)
{
	volatile cbd_t		*rbdf;
	volatile scc_uart_t	*up;
	volatile ccsr_cpm_t	*cpm = (ccsr_cpm_t *)CONFIG_SYS_MPC85xx_CPM_ADDR;
	unsigned char		c;

	up = (scc_uart_t *)&(cpm->im_dprambase[PROFF_SCC]);
	rbdf = (cbd_t *)&(cpm->im_dprambase[up->scc_genscc.scc_rbase]);

	/* Wait for character to show up.
	 */
	while (rbdf->cbd_sc & BD_SC_EMPTY)
		;

	/* Grab the char and clear the buffer again.
	 */
	c = *(volatile unsigned char *)rbdf->cbd_bufaddr;
	rbdf->cbd_sc |= BD_SC_EMPTY;

	return (c);
}

int
serial_tstc()
{
	volatile cbd_t		*rbdf;
	volatile scc_uart_t	*up;
	volatile ccsr_cpm_t	*cpm = (ccsr_cpm_t *)CONFIG_SYS_MPC85xx_CPM_ADDR;

	up = (scc_uart_t *)&(cpm->im_dprambase[PROFF_SCC]);
	rbdf = (cbd_t *)&(cpm->im_dprambase[up->scc_genscc.scc_rbase]);

	return ((rbdf->cbd_sc & BD_SC_EMPTY) == 0);
}

#endif	/* CONFIG_CONS_ON_SCC */