diff options
| -rw-r--r-- | src/mainboard/google/storm/Makefile.inc | 3 | ||||
| -rw-r--r-- | src/mainboard/google/storm/boardid.c | 50 |
2 files changed, 52 insertions, 1 deletions
diff --git a/src/mainboard/google/storm/Makefile.inc b/src/mainboard/google/storm/Makefile.inc index 4a47c9ec85..907638a3ef 100644 --- a/src/mainboard/google/storm/Makefile.inc +++ b/src/mainboard/google/storm/Makefile.inc @@ -22,5 +22,6 @@ bootblock-y += cdp.c romstage-y += romstage.c romstage-y += cdp.c -ramstage-y += mainboard.c +ramstage-y += boardid.c ramstage-y += cdp.c +ramstage-y += mainboard.c diff --git a/src/mainboard/google/storm/boardid.c b/src/mainboard/google/storm/boardid.c new file mode 100644 index 0000000000..7cbb92a701 --- /dev/null +++ b/src/mainboard/google/storm/boardid.c @@ -0,0 +1,50 @@ +/* + * 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; +} |