drivers/misc/cbmem_console.c

   1 /*
   2  * Copyright (C) 2011 The ChromiumOS Authors.  All rights reserved.
   3  *
   4  * SPDX-License-Identifier:     GPL-2.0
   5  */
   6
   7 #include <common.h>
   8 #include <console.h>
   9 #ifndef CONFIG_SYS_COREBOOT
  10 #error This driver requires coreboot
  11 #endif
  12
  13 #include <asm/arch/sysinfo.h>
  14
  15 struct cbmem_console {
  16         u32 buffer_size;
  17         u32 buffer_cursor;
  18         u8  buffer_body[0];
  19 }  __attribute__ ((__packed__));
  20
  21 static struct cbmem_console *cbmem_console_p;
  22
  23 void cbmemc_putc(struct stdio_dev *dev, char data)
  24 {
  25         int cursor;
  26
  27         cursor = cbmem_console_p->buffer_cursor++;
  28         if (cursor < cbmem_console_p->buffer_size)
  29                 cbmem_console_p->buffer_body[cursor] = data;
  30 }
  31
  32 void cbmemc_puts(struct stdio_dev *dev, const char *str)
  33 {
  34         char c;
  35
  36         while ((c = *str++) != 0)
  37                 cbmemc_putc(dev, c);
  38 }
  39
  40 int cbmemc_init(void)
  41 {
  42         int rc;
  43         struct stdio_dev cons_dev;
  44         cbmem_console_p = lib_sysinfo.cbmem_cons;
  45
  46         memset(&cons_dev, 0, sizeof(cons_dev));
  47
  48         strcpy(cons_dev.name, "cbmem");
  49         cons_dev.flags = DEV_FLAGS_OUTPUT; /* Output only */
  50         cons_dev.putc  = cbmemc_putc;
  51         cons_dev.puts  = cbmemc_puts;
  52
  53         rc = stdio_register(&cons_dev);
  54
  55         return (rc == 0) ? 1 : rc;
  56 }