51 lines
1.7 KiB
C
51 lines
1.7 KiB
C
|
/*
|
||
|
|
* This file is part of the coreboot project.
|
||
|
|
*
|
||
|
|
* Copyright 2014 Google Inc.
|
||
|
|
*
|
||
|
|
* This program is free software; you can redistribute it and/or modify
|
||
|
|
* it under the terms of the GNU General Public License as published by
|
||
|
|
* the Free Software Foundation; version 2 of the License.
|
||
|
|
*
|
||
|
|
* This program is distributed in the hope that it will be useful,
|
||
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
|
|
* GNU General Public License for more details.
|
||
|
|
*
|
||
|
|
* You should have received a copy of the GNU General Public License
|
||
|
|
* along with this program; if not, write to the Free Software
|
||
|
|
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <stdlib.h>
|
||
|
|
#include <boardid.h>
|
||
|
|
#include <gpiolib.h>
|
||
|
|
#include <console/console.h>
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Storm boards dedicate to the board ID three GPIOs in tertiary mode: 29, 30
|
||
|
|
* and 68. On proto0 GPIO68 is used and tied low, so it reads as 'zero' by
|
||
|
|
* gpio_board_id(), whereas the other two pins are not connected and read as
|
||
|
|
* 'two'. This results in gpio_board_id() returning 8 on proto0.
|
||
|
|
*
|
||
|
|
* Three tertitiary signals could represent 27 different values. To make
|
||
|
|
* calculated board ID value continuous and starting at zero, offset the
|
||
|
|
* calculated value by 19 (i.e. 27 - 8) and return modulo 27 of the offset
|
||
|
|
* number. This results in proto0 returning zero as the board ID, the future
|
||
|
|
* revisions will have the inputs configured to match the actual board
|
||
|
|
* revision.
|
||
|
|
*/
|
||
|
|
|
||
|
|
uint8_t board_id(void)
|
||
|
|
{
|
||
|
|
uint8_t bid;
|
||
|
|
gpio_t hw_rev_gpios[] = {68, 30, 29};
|
||
|
|
int offset = 19;
|
||
|
|
|
||
|
|
bid = gpio_board_id(hw_rev_gpios, ARRAY_SIZE(hw_rev_gpios), 1);
|
||
|
|
bid = (bid + offset) % 27;
|
||
|
|
printk(BIOS_INFO, "Board ID %d\n", bid);
|
||
|
|
|
||
|
|
return bid;
|
||
|
|
}
|