1 /*        $NetBSD: zs_sbdio.c,v 1.14 2021/08/07 16:18:53 thorpej Exp $          */
2 
3 /*-
4  * Copyright (c) 1996, 2005 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Gordon W. Ross.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * Zilog Z8530 Dual UART driver (machine-dependent part)
34  *
35  * Runs two serial lines per chip using slave drivers.
36  * Plain tty/async lines use the zs_async slave.
37  */
38 
39 #include <sys/cdefs.h>
40 __KERNEL_RCSID(0, "$NetBSD: zs_sbdio.c,v 1.14 2021/08/07 16:18:53 thorpej Exp $");
41 
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/device.h>
45 #include <sys/tty.h>
46 #include <sys/conf.h>
47 #include <sys/intr.h>
48 
49 #include <dev/cons.h>
50 #include <dev/ic/z8530reg.h>
51 
52 #include <mips/locore.h>
53 
54 #include <machine/sbdiovar.h>
55 #include <machine/z8530var.h>
56 
57 #define ZS_DEFSPEED 9600
58 #define PCLK                  (9600 * 512)                  /* 4.915200MHz */
59 
60 /* The layout of this is hardware-dependent (padding, order). */
61 struct zschan {
62           volatile uint8_t zc_csr;      /* ctrl, status, and indirect access */
63           uint8_t padding1[3];
64           volatile uint8_t zc_data;     /* data */
65           uint8_t padding2[3];
66 } __attribute__((__packed__));
67 
68 struct zsdevice {
69           /* Yes, they are backwards. */
70           struct    zschan zs_chan_b;
71           struct    zschan zs_chan_a;
72 } __attribute__((__packed__));
73 
74 static uint8_t zs_init_reg[16] = {
75           0,                                      /*  0: CMD (reset, etc.) */
76           0,                                      /*  1: No interrupts yet. */
77           0,                                      /*  2: IVECT EWS-UX don't set this. */
78           ZSWR3_RX_8 | ZSWR3_RX_ENABLE,
79           ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP,
80           ZSWR5_TX_8 | ZSWR5_TX_ENABLE,
81           0,                                      /*  6: TXSYNC/SYNCLO */
82           0,                                      /*  7: RXSYNC/SYNCHI */
83           0,                                      /*  8: alias for data port */
84           ZSWR9_MASTER_IE,
85           0,                                      /* 10: Misc. TX/RX control bits */
86           ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD,
87           BPS_TO_TCONST((PCLK/16), ZS_DEFSPEED), /* 12: BAUDLO (default=9600) */
88           0,                                      /*13: BAUDHI (default=9600) */
89           ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK,
90           ZSWR15_BREAK_IE,
91 };
92 
93 static int zs_sbdio_match(device_t, cfdata_t, void *);
94 static void zs_sbdio_attach(device_t, device_t, void *);
95 
96 CFATTACH_DECL_NEW(zsc_sbdio, sizeof(struct zsc_softc),
97     zs_sbdio_match, zs_sbdio_attach, NULL, NULL);
98 
99 int
zs_sbdio_match(device_t parent,cfdata_t cf,void * aux)100 zs_sbdio_match(device_t parent, cfdata_t cf, void *aux)
101 {
102           struct sbdio_attach_args *sa = aux;
103 
104           return strcmp(sa->sa_name, "zsc") ? 0 : 1;
105 }
106 
107 void
zs_sbdio_attach(device_t parent,device_t self,void * aux)108 zs_sbdio_attach(device_t parent, device_t self, void *aux)
109 {
110           struct zsc_softc *zsc = device_private(self);
111           struct sbdio_attach_args *sa = aux;
112           struct zsc_attach_args zsc_args;
113           struct zschan *zc;
114           struct zs_chanstate *cs;
115           struct zsdevice *zs_addr;
116           int s, channel;
117 
118           zsc->zsc_dev = self;
119           aprint_normal("\n");
120 
121           zs_addr = (void *)MIPS_PHYS_TO_KSEG1(sa->sa_addr1);
122           zsc->zsc_flags = sa->sa_flags;
123 
124           /*
125            * Initialize software state for each channel.
126            */
127           for (channel = 0; channel < 2; channel++) {
128                     zsc_args.channel = channel;
129                     zsc_args.hwflags = 0;
130                     cs = &zsc->zsc_cs_store[channel];
131                     zsc->zsc_cs[channel] = cs;
132 
133                     cs->cs_channel = channel;
134                     cs->cs_private = NULL;
135                     cs->cs_ops = &zsops_null;
136 
137                     if (channel == 0)
138                               zc = &zs_addr->zs_chan_a;
139                     else
140                               zc = &zs_addr->zs_chan_b;
141 
142                     if (zc == zs_consaddr) {
143                               memcpy(cs, zs_conscs, sizeof(struct zs_chanstate));
144                               zs_conscs = cs;
145                               zsc_args.hwflags = ZS_HWFLAG_CONSOLE;
146                     } else {
147                               cs->cs_reg_csr  = &zc->zc_csr;
148                               cs->cs_reg_data = &zc->zc_data;
149                               memcpy(cs->cs_creg, zs_init_reg, 16);
150                               memcpy(cs->cs_preg, zs_init_reg, 16);
151                               cs->cs_defspeed = ZS_DEFSPEED;
152                               zsc_args.hwflags = 0;
153                     }
154 
155                     zs_lock_init(cs);
156                     cs->cs_brg_clk = PCLK / 16;
157                     cs->cs_defcflag = zs_def_cflag;
158 
159                     /* Make these correspond to cs_defcflag (-crtscts) */
160                     cs->cs_rr0_dcd = ZSRR0_DCD;
161                     cs->cs_rr0_cts = 0;
162                     cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
163                     cs->cs_wr5_rts = 0;
164 
165                     /*
166                      * Clear the master interrupt enable.
167                      * The INTENA is common to both channels,
168                      * so just do it on the A channel.
169                      */
170                     if (channel == 0) {
171                               zs_write_reg(cs, 9, 0);
172                     }
173 
174                     /*
175                      * Look for a child driver for this channel.
176                      * The child attach will setup the hardware.
177                      */
178                     if (!config_found(self, (void *)&zsc_args, zs_print,
179                         CFARGS_NONE)) {
180                               /* No sub-driver.  Just reset it. */
181                               uint8_t reset = (channel == 0) ?
182                                   ZSWR9_A_RESET : ZSWR9_B_RESET;
183                               s = splhigh();
184                               zs_write_reg(cs, 9, reset);
185                               splx(s);
186                     }
187           }
188 
189           zsc->zsc_si = softint_establish(SOFTINT_SERIAL,
190               (void (*)(void *))zsc_intr_soft, zsc);
191           intr_establish(sa->sa_irq, zshard, zsc);
192 
193           /*
194            * Set the master interrupt enable and interrupt vector.
195            * (common to both channels, do it on A)
196            */
197           cs = zsc->zsc_cs[0];
198           s = splhigh();
199           /* interrupt vector */
200           zs_write_reg(cs, 2, zs_init_reg[2]);
201           /* master interrupt control (enable) */
202           zs_write_reg(cs, 9, zs_init_reg[9]);
203           splx(s);
204 }
205 
206 /*
207  * console stuff
208  */
209 
210 static void zs_sbdio_cnprobe(struct consdev *);
211 static void zs_sbdio_cninit(struct consdev *);
212 
213 struct consdev consdev_zs_sbdio = {
214           zs_sbdio_cnprobe,
215           zs_sbdio_cninit,
216           zscngetc,
217           zscnputc,
218           nullcnpollc,
219           NULL,
220           NULL,
221           NULL,
222           NODEV,
223           CN_DEAD
224 };
225 
226 static void
zs_sbdio_cnprobe(struct consdev * cn)227 zs_sbdio_cnprobe(struct consdev *cn)
228 {
229 
230           /* not used */
231 }
232 
233 static void
zs_sbdio_cninit(struct consdev * cn)234 zs_sbdio_cninit(struct consdev *cn)
235 {
236           struct zs_chanstate *cs;
237           struct zschan *zc;
238 
239           zc = zs_consaddr;
240           cs = zs_conscs;
241 
242           /* Setup temporary chanstate. */
243           cs->cs_reg_csr  = &zc->zc_csr;
244           cs->cs_reg_data = &zc->zc_data;
245 
246           /* Initialize the pending registers. */
247           memcpy(cs->cs_preg, zs_init_reg, 16);
248           cs->cs_preg[5] |= ZSWR5_DTR | ZSWR5_RTS;
249 
250           cs->cs_brg_clk = PCLK / 16;
251           cs->cs_defspeed = ZS_DEFSPEED;
252           zs_set_speed(cs, ZS_DEFSPEED);
253 
254           /* Clear the master interrupt enable. */
255           zs_write_reg(cs, 9, 0);
256 
257           /* Reset the whole SCC chip. */
258           zs_write_reg(cs, 9, ZSWR9_HARD_RESET);
259 
260           /* Copy "pending" to "current" and H/W */
261           zs_loadchannelregs(cs);
262 }
263