/* * This file is part of the libpayload project. * * Copyright (c) 2012 Google Inc. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include <libpayload.h> #include <stdint.h> struct cbmem_console { uint32_t size; uint32_t cursor; uint8_t body[0]; } __attribute__ ((__packed__)); #define CURSOR_MASK ((1 << 28) - 1) #define OVERFLOW (1 << 31) static struct cbmem_console *cbmem_console_p; static struct console_output_driver cbmem_console_driver = { .write = &cbmem_console_write, }; static void do_write(const void *buffer, size_t count) { memcpy(cbmem_console_p->body + (cbmem_console_p->cursor & CURSOR_MASK), buffer, count); cbmem_console_p->cursor += count; } void cbmem_console_init(void) { cbmem_console_p = lib_sysinfo.cbmem_cons; if (cbmem_console_p && cbmem_console_p->size) console_add_output_driver(&cbmem_console_driver); } void cbmem_console_write(const void *buffer, size_t count) { while ((cbmem_console_p->cursor & CURSOR_MASK) + count >= cbmem_console_p->size) { size_t still_fits = cbmem_console_p->size - (cbmem_console_p->cursor & CURSOR_MASK); do_write(buffer, still_fits); cbmem_console_p->cursor &= ~CURSOR_MASK; cbmem_console_p->cursor |= OVERFLOW; buffer += still_fits; count -= still_fits; } do_write(buffer, count); }