/*
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* SPDX-License-Identifier: BSD-2-Clause
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*
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* Copyright (c) 2020 Western Digital Corporation or its affiliates.
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*
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* Authors:
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* Anup Patel <anup.patel@wdc.com>
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*/
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#include <libfdt.h>
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#include <sbi/sbi_scratch.h>
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#include <sbi_utils/fdt/fdt_helper.h>
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#include <sbi_utils/serial/fdt_serial.h>
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extern struct fdt_serial fdt_serial_uart8250;
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extern struct fdt_serial fdt_serial_sifive;
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extern struct fdt_serial fdt_serial_htif;
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extern struct fdt_serial fdt_serial_shakti;
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static struct fdt_serial *serial_drivers[] = {
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&fdt_serial_uart8250,
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&fdt_serial_sifive,
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&fdt_serial_htif,
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&fdt_serial_shakti,
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};
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static void dummy_putc(char ch)
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{
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}
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static int dummy_getc(void)
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{
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return -1;
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}
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static struct fdt_serial dummy = {
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.match_table = NULL,
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.init = NULL,
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.putc = dummy_putc,
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.getc = dummy_getc,
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};
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static struct fdt_serial *current_driver = &dummy;
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void fdt_serial_putc(char ch)
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{
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current_driver->putc(ch);
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}
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int fdt_serial_getc(void)
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{
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return current_driver->getc();
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}
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int fdt_serial_init(void)
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{
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const void *prop;
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struct fdt_serial *drv;
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const struct fdt_match *match;
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int pos, noff = -1, len, coff, rc;
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void *fdt = sbi_scratch_thishart_arg1_ptr();
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/* Find offset of node pointed by stdout-path */
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coff = fdt_path_offset(fdt, "/chosen");
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if (-1 < coff) {
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prop = fdt_getprop(fdt, coff, "stdout-path", &len);
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if (prop && len)
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noff = fdt_path_offset(fdt, prop);
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}
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/* First check DT node pointed by stdout-path */
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for (pos = 0; pos < array_size(serial_drivers) && -1 < noff; pos++) {
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drv = serial_drivers[pos];
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match = fdt_match_node(fdt, noff, drv->match_table);
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if (!match)
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continue;
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if (drv->init) {
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rc = drv->init(fdt, noff, match);
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if (rc)
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return rc;
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}
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current_driver = drv;
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break;
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}
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/* Check if we found desired driver */
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if (current_driver != &dummy)
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goto done;
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/* Lastly check all DT nodes */
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for (pos = 0; pos < array_size(serial_drivers); pos++) {
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drv = serial_drivers[pos];
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noff = fdt_find_match(fdt, -1, drv->match_table, &match);
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if (noff < 0)
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continue;
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if (drv->init) {
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rc = drv->init(fdt, noff, match);
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if (rc)
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return rc;
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}
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current_driver = drv;
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break;
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}
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done:
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return 0;
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}
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