uboot/drivers/serial/serial_sh.c
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   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * SuperH SCIF device driver.
   4 * Copyright (C) 2013  Renesas Electronics Corporation
   5 * Copyright (C) 2007,2008,2010, 2014 Nobuhiro Iwamatsu
   6 * Copyright (C) 2002 - 2008  Paul Mundt
   7 */
   8
   9#include <common.h>
  10#include <errno.h>
  11#include <clk.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
  20DECLARE_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)
  26static int scif_rxfill(struct uart_port *port)
  27{
  28        return sci_in(port, SCRFDR) & 0xff;
  29}
  30#elif defined(CONFIG_CPU_SH7763)
  31static 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)
  43static 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
  51static int scif_rxfill(struct uart_port *port)
  52{
  53        return sci_in(port, SCFDR) & SCIF_RFDC_MASK;
  54}
  55#endif
  56
  57static 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
  68static void
  69sh_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
  81static 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
  89static 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
 101static int serial_rx_fifo_level(struct uart_port *port)
 102{
 103        return scif_rxfill(port);
 104}
 105
 106static 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
 116static 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
 129static 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#if CONFIG_IS_ENABLED(DM_SERIAL)
 152
 153static 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
 160static 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
 167static 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
 174static 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
 184static 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
 199static 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#if CONFIG_IS_ENABLED(OF_CONTROL)
 207static 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
 214static int sh_serial_ofdata_to_platdata(struct udevice *dev)
 215{
 216        struct sh_serial_platdata *plat = dev_get_platdata(dev);
 217        struct clk sh_serial_clk;
 218        fdt_addr_t addr;
 219        int ret;
 220
 221        addr = devfdt_get_addr(dev);
 222        if (!addr)
 223                return -EINVAL;
 224
 225        plat->base = addr;
 226
 227        ret = clk_get_by_name(dev, "fck", &sh_serial_clk);
 228        if (!ret) {
 229                ret = clk_enable(&sh_serial_clk);
 230                if (!ret)
 231                        plat->clk = clk_get_rate(&sh_serial_clk);
 232        } else {
 233                plat->clk = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev),
 234                                           "clock", 1);
 235        }
 236
 237        plat->type = dev_get_driver_data(dev);
 238        return 0;
 239}
 240#endif
 241
 242U_BOOT_DRIVER(serial_sh) = {
 243        .name   = "serial_sh",
 244        .id     = UCLASS_SERIAL,
 245        .of_match = of_match_ptr(sh_serial_id),
 246        .ofdata_to_platdata = of_match_ptr(sh_serial_ofdata_to_platdata),
 247        .platdata_auto_alloc_size = sizeof(struct sh_serial_platdata),
 248        .probe  = sh_serial_probe,
 249        .ops    = &sh_serial_ops,
 250        .flags  = DM_FLAG_PRE_RELOC,
 251        .priv_auto_alloc_size = sizeof(struct uart_port),
 252};
 253
 254#else /* CONFIG_DM_SERIAL */
 255
 256#if defined(CONFIG_CONS_SCIF0)
 257# define SCIF_BASE      SCIF0_BASE
 258#elif defined(CONFIG_CONS_SCIF1)
 259# define SCIF_BASE      SCIF1_BASE
 260#elif defined(CONFIG_CONS_SCIF2)
 261# define SCIF_BASE      SCIF2_BASE
 262#elif defined(CONFIG_CONS_SCIF3)
 263# define SCIF_BASE      SCIF3_BASE
 264#elif defined(CONFIG_CONS_SCIF4)
 265# define SCIF_BASE      SCIF4_BASE
 266#elif defined(CONFIG_CONS_SCIF5)
 267# define SCIF_BASE      SCIF5_BASE
 268#elif defined(CONFIG_CONS_SCIF6)
 269# define SCIF_BASE      SCIF6_BASE
 270#elif defined(CONFIG_CONS_SCIF7)
 271# define SCIF_BASE      SCIF7_BASE
 272#elif defined(CONFIG_CONS_SCIFA0)
 273# define SCIF_BASE      SCIFA0_BASE
 274#else
 275# error "Default SCIF doesn't set....."
 276#endif
 277
 278#if defined(CONFIG_SCIF_A)
 279        #define SCIF_BASE_PORT  PORT_SCIFA
 280#elif defined(CONFIG_SCI)
 281        #define SCIF_BASE_PORT  PORT_SCI
 282#else
 283        #define SCIF_BASE_PORT  PORT_SCIF
 284#endif
 285
 286static struct uart_port sh_sci = {
 287        .membase        = (unsigned char *)SCIF_BASE,
 288        .mapbase        = SCIF_BASE,
 289        .type           = SCIF_BASE_PORT,
 290#ifdef CONFIG_SCIF_USE_EXT_CLK
 291        .clk_mode =     EXT_CLK,
 292#endif
 293};
 294
 295static void sh_serial_setbrg(void)
 296{
 297        DECLARE_GLOBAL_DATA_PTR;
 298        struct uart_port *port = &sh_sci;
 299
 300        sh_serial_setbrg_generic(port, CONFIG_SH_SCIF_CLK_FREQ, gd->baudrate);
 301}
 302
 303static int sh_serial_init(void)
 304{
 305        struct uart_port *port = &sh_sci;
 306
 307        sh_serial_init_generic(port);
 308        serial_setbrg();
 309
 310        return 0;
 311}
 312
 313static void sh_serial_putc(const char c)
 314{
 315        struct uart_port *port = &sh_sci;
 316
 317        if (c == '\n') {
 318                while (1) {
 319                        if  (serial_raw_putc(port, '\r') != -EAGAIN)
 320                                break;
 321                }
 322        }
 323        while (1) {
 324                if  (serial_raw_putc(port, c) != -EAGAIN)
 325                        break;
 326        }
 327}
 328
 329static int sh_serial_tstc(void)
 330{
 331        struct uart_port *port = &sh_sci;
 332
 333        return sh_serial_tstc_generic(port);
 334}
 335
 336static int sh_serial_getc(void)
 337{
 338        struct uart_port *port = &sh_sci;
 339        int ch;
 340
 341        while (1) {
 342                ch = sh_serial_getc_generic(port);
 343                if (ch != -EAGAIN)
 344                        break;
 345        }
 346
 347        return ch;
 348}
 349
 350static struct serial_device sh_serial_drv = {
 351        .name   = "sh_serial",
 352        .start  = sh_serial_init,
 353        .stop   = NULL,
 354        .setbrg = sh_serial_setbrg,
 355        .putc   = sh_serial_putc,
 356        .puts   = default_serial_puts,
 357        .getc   = sh_serial_getc,
 358        .tstc   = sh_serial_tstc,
 359};
 360
 361void sh_serial_initialize(void)
 362{
 363        serial_register(&sh_serial_drv);
 364}
 365
 366__weak struct serial_device *default_serial_console(void)
 367{
 368        return &sh_serial_drv;
 369}
 370#endif /* CONFIG_DM_SERIAL */
 371