coreboot-libre-fam15h-rdimm/payloads/libpayload/drivers/cbmem_console.c

78 lines
2.6 KiB
C

/*
* 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];
} __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);
}