1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2003 Motorola Inc.
4  * Xianghua Xiao (X.Xiao@motorola.com)
5  * Modified based on 8260 for 8560.
6  *
7  * (C) Copyright 2000
8  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
9  *
10  * Hacked for MPC8260 by Murray.Jensen@cmst.csiro.au, 19-Oct-00.
11  */
12 
13 /*
14  * Minimal serial functions needed to use one of the SCC ports
15  * as serial console interface.
16  */
17 
18 #include <common.h>
19 #include <asm/cpm_85xx.h>
20 #include <serial.h>
21 #include <asm/global_data.h>
22 #include <linux/compiler.h>
23 
24 DECLARE_GLOBAL_DATA_PTR;
25 
26 #if defined(CONFIG_CONS_ON_SCC)
27 
28 #if CONFIG_CONS_INDEX == 1	/* Console on SCC1 */
29 
30 #define SCC_INDEX		0
31 #define PROFF_SCC		PROFF_SCC1
32 #define CMXSCR_MASK		(CMXSCR_GR1|CMXSCR_SC1|\
33 					CMXSCR_RS1CS_MSK|CMXSCR_TS1CS_MSK)
34 #define CMXSCR_VALUE		(CMXSCR_RS1CS_BRG1|CMXSCR_TS1CS_BRG1)
35 #define CPM_CR_SCC_PAGE		CPM_CR_SCC1_PAGE
36 #define CPM_CR_SCC_SBLOCK	CPM_CR_SCC1_SBLOCK
37 
38 #elif CONFIG_CONS_INDEX == 2	/* Console on SCC2 */
39 
40 #define SCC_INDEX		1
41 #define PROFF_SCC		PROFF_SCC2
42 #define CMXSCR_MASK		(CMXSCR_GR2|CMXSCR_SC2|\
43 					CMXSCR_RS2CS_MSK|CMXSCR_TS2CS_MSK)
44 #define CMXSCR_VALUE		(CMXSCR_RS2CS_BRG2|CMXSCR_TS2CS_BRG2)
45 #define CPM_CR_SCC_PAGE		CPM_CR_SCC2_PAGE
46 #define CPM_CR_SCC_SBLOCK	CPM_CR_SCC2_SBLOCK
47 
48 #elif CONFIG_CONS_INDEX == 3	/* Console on SCC3 */
49 
50 #define SCC_INDEX		2
51 #define PROFF_SCC		PROFF_SCC3
52 #define CMXSCR_MASK		(CMXSCR_GR3|CMXSCR_SC3|\
53 					CMXSCR_RS3CS_MSK|CMXSCR_TS3CS_MSK)
54 #define CMXSCR_VALUE		(CMXSCR_RS3CS_BRG3|CMXSCR_TS3CS_BRG3)
55 #define CPM_CR_SCC_PAGE		CPM_CR_SCC3_PAGE
56 #define CPM_CR_SCC_SBLOCK	CPM_CR_SCC3_SBLOCK
57 
58 #elif CONFIG_CONS_INDEX == 4	/* Console on SCC4 */
59 
60 #define SCC_INDEX		3
61 #define PROFF_SCC		PROFF_SCC4
62 #define CMXSCR_MASK		(CMXSCR_GR4|CMXSCR_SC4|\
63 					CMXSCR_RS4CS_MSK|CMXSCR_TS4CS_MSK)
64 #define CMXSCR_VALUE		(CMXSCR_RS4CS_BRG4|CMXSCR_TS4CS_BRG4)
65 #define CPM_CR_SCC_PAGE		CPM_CR_SCC4_PAGE
66 #define CPM_CR_SCC_SBLOCK	CPM_CR_SCC4_SBLOCK
67 
68 #else
69 
70 #error "console not correctly defined"
71 
72 #endif
73 
mpc85xx_serial_init(void)74 static int mpc85xx_serial_init(void)
75 {
76 	volatile ccsr_cpm_t *cpm = (ccsr_cpm_t *)CONFIG_SYS_MPC85xx_CPM_ADDR;
77 	volatile ccsr_cpm_scc_t *sp;
78 	volatile scc_uart_t *up;
79 	volatile cbd_t *tbdf, *rbdf;
80 	volatile ccsr_cpm_cp_t *cp = &(cpm->im_cpm_cp);
81 	uint	dpaddr;
82 
83 	/* initialize pointers to SCC */
84 
85 	sp = (ccsr_cpm_scc_t *) &(cpm->im_cpm_scc[SCC_INDEX]);
86 	up = (scc_uart_t *)&(cpm->im_dprambase[PROFF_SCC]);
87 
88 	/* Disable transmitter/receiver.
89 	*/
90 	sp->gsmrl &= ~(SCC_GSMRL_ENR | SCC_GSMRL_ENT);
91 
92 	/* put the SCC channel into NMSI (non multiplexd serial interface)
93 	 * mode and wire the selected SCC Tx and Rx clocks to BRGx (15-15).
94 	 */
95 	cpm->im_cpm_mux.cmxscr = \
96 		(cpm->im_cpm_mux.cmxscr&~CMXSCR_MASK)|CMXSCR_VALUE;
97 
98 	/* Set up the baud rate generator.
99 	*/
100 	serial_setbrg ();
101 
102 	/* Allocate space for two buffer descriptors in the DP ram.
103 	 * damm: allocating space after the two buffers for rx/tx data
104 	 */
105 
106 	dpaddr = m8560_cpm_dpalloc((2 * sizeof (cbd_t)) + 2, 16);
107 
108 	/* Set the physical address of the host memory buffers in
109 	 * the buffer descriptors.
110 	 */
111 	rbdf = (cbd_t *)&(cpm->im_dprambase[dpaddr]);
112 	rbdf->cbd_bufaddr = (uint) (rbdf+2);
113 	rbdf->cbd_sc = BD_SC_EMPTY | BD_SC_WRAP;
114 	tbdf = rbdf + 1;
115 	tbdf->cbd_bufaddr = ((uint) (rbdf+2)) + 1;
116 	tbdf->cbd_sc = BD_SC_WRAP;
117 
118 	/* Set up the uart parameters in the parameter ram.
119 	*/
120 	up->scc_genscc.scc_rbase = dpaddr;
121 	up->scc_genscc.scc_tbase = dpaddr+sizeof(cbd_t);
122 	up->scc_genscc.scc_rfcr = CPMFCR_EB;
123 	up->scc_genscc.scc_tfcr = CPMFCR_EB;
124 	up->scc_genscc.scc_mrblr = 1;
125 	up->scc_maxidl = 0;
126 	up->scc_brkcr = 1;
127 	up->scc_parec = 0;
128 	up->scc_frmec = 0;
129 	up->scc_nosec = 0;
130 	up->scc_brkec = 0;
131 	up->scc_uaddr1 = 0;
132 	up->scc_uaddr2 = 0;
133 	up->scc_toseq = 0;
134 	up->scc_char1 = up->scc_char2 = up->scc_char3 = up->scc_char4 = 0x8000;
135 	up->scc_char5 = up->scc_char6 = up->scc_char7 = up->scc_char8 = 0x8000;
136 	up->scc_rccm = 0xc0ff;
137 
138 	/* Mask all interrupts and remove anything pending.
139 	*/
140 	sp->sccm = 0;
141 	sp->scce = 0xffff;
142 
143 	/* Set 8 bit FIFO, 16 bit oversampling and UART mode.
144 	*/
145 	sp->gsmrh = SCC_GSMRH_RFW;	/* 8 bit FIFO */
146 	sp->gsmrl = \
147 		SCC_GSMRL_TDCR_16 | SCC_GSMRL_RDCR_16 | SCC_GSMRL_MODE_UART;
148 
149 	/* Set CTS no flow control, 1 stop bit, 8 bit character length,
150 	 * normal async UART mode, no parity
151 	 */
152 	sp->psmr = SCU_PSMR_CL;
153 
154 	/* execute the "Init Rx and Tx params" CP command.
155 	*/
156 
157 	while (cp->cpcr & CPM_CR_FLG)  /* wait if cp is busy */
158 	  ;
159 
160 	cp->cpcr = mk_cr_cmd(CPM_CR_SCC_PAGE, CPM_CR_SCC_SBLOCK,
161 					0, CPM_CR_INIT_TRX) | CPM_CR_FLG;
162 
163 	while (cp->cpcr & CPM_CR_FLG)  /* wait if cp is busy */
164 	  ;
165 
166 	/* Enable transmitter/receiver.
167 	*/
168 	sp->gsmrl |= SCC_GSMRL_ENR | SCC_GSMRL_ENT;
169 
170 	return (0);
171 }
172 
mpc85xx_serial_setbrg(void)173 static void mpc85xx_serial_setbrg(void)
174 {
175 #if defined(CONFIG_CONS_USE_EXTC)
176 	m8560_cpm_extcbrg(SCC_INDEX, gd->baudrate,
177 		CONFIG_CONS_EXTC_RATE, CONFIG_CONS_EXTC_PINSEL);
178 #else
179 	m8560_cpm_setbrg(SCC_INDEX, gd->baudrate);
180 #endif
181 }
182 
mpc85xx_serial_putc(const char c)183 static void mpc85xx_serial_putc(const char c)
184 {
185 	volatile scc_uart_t	*up;
186 	volatile cbd_t		*tbdf;
187 	volatile ccsr_cpm_t	*cpm = (ccsr_cpm_t *)CONFIG_SYS_MPC85xx_CPM_ADDR;
188 
189 	if (c == '\n')
190 		serial_putc ('\r');
191 
192 	up = (scc_uart_t *)&(cpm->im_dprambase[PROFF_SCC]);
193 	tbdf = (cbd_t *)&(cpm->im_dprambase[up->scc_genscc.scc_tbase]);
194 
195 	/* Wait for last character to go.
196 	 */
197 	while (tbdf->cbd_sc & BD_SC_READY)
198 		;
199 
200 	/* Load the character into the transmit buffer.
201 	 */
202 	*(volatile char *)tbdf->cbd_bufaddr = c;
203 	tbdf->cbd_datlen = 1;
204 	tbdf->cbd_sc |= BD_SC_READY;
205 }
206 
mpc85xx_serial_getc(void)207 static int mpc85xx_serial_getc(void)
208 {
209 	volatile cbd_t		*rbdf;
210 	volatile scc_uart_t	*up;
211 	volatile ccsr_cpm_t	*cpm = (ccsr_cpm_t *)CONFIG_SYS_MPC85xx_CPM_ADDR;
212 	unsigned char		c;
213 
214 	up = (scc_uart_t *)&(cpm->im_dprambase[PROFF_SCC]);
215 	rbdf = (cbd_t *)&(cpm->im_dprambase[up->scc_genscc.scc_rbase]);
216 
217 	/* Wait for character to show up.
218 	 */
219 	while (rbdf->cbd_sc & BD_SC_EMPTY)
220 		;
221 
222 	/* Grab the char and clear the buffer again.
223 	 */
224 	c = *(volatile unsigned char *)rbdf->cbd_bufaddr;
225 	rbdf->cbd_sc |= BD_SC_EMPTY;
226 
227 	return (c);
228 }
229 
mpc85xx_serial_tstc(void)230 static int mpc85xx_serial_tstc(void)
231 {
232 	volatile cbd_t		*rbdf;
233 	volatile scc_uart_t	*up;
234 	volatile ccsr_cpm_t	*cpm = (ccsr_cpm_t *)CONFIG_SYS_MPC85xx_CPM_ADDR;
235 
236 	up = (scc_uart_t *)&(cpm->im_dprambase[PROFF_SCC]);
237 	rbdf = (cbd_t *)&(cpm->im_dprambase[up->scc_genscc.scc_rbase]);
238 
239 	return ((rbdf->cbd_sc & BD_SC_EMPTY) == 0);
240 }
241 
242 static struct serial_device mpc85xx_serial_drv = {
243 	.name	= "mpc85xx_serial",
244 	.start	= mpc85xx_serial_init,
245 	.stop	= NULL,
246 	.setbrg	= mpc85xx_serial_setbrg,
247 	.putc	= mpc85xx_serial_putc,
248 	.puts	= default_serial_puts,
249 	.getc	= mpc85xx_serial_getc,
250 	.tstc	= mpc85xx_serial_tstc,
251 };
252 
mpc85xx_serial_initialize(void)253 void mpc85xx_serial_initialize(void)
254 {
255 	serial_register(&mpc85xx_serial_drv);
256 }
257 
default_serial_console(void)258 __weak struct serial_device *default_serial_console(void)
259 {
260 	return &mpc85xx_serial_drv;
261 }
262 #endif	/* CONFIG_CONS_ON_SCC */
263