diff options
| author | Matt DeVillier <matt.devillier@gmail.com> | 2017-02-07 22:07:56 -0600 |
|---|---|---|
| committer | Nico Huber <nico.h@gmx.de> | 2017-02-14 13:03:53 +0100 |
| commit | 474a7c51cecfd2e37b315da9cfb25607f3ad84f1 (patch) | |
| tree | 126b3ae7d166557e9c9692d11a7af1c5ca1e565a /src | |
| parent | d81078d944bd78b1dca559444d938f18d4004205 (diff) | |
google/rambi: add explicit pull-down for ram-id
Some variants need the internal pull resistor on GPIO_SSUS_40
set explicitly to pull down rather than disabling the pull,
in order for the ram-id to be read correctly via GPIO.
Correct this by adding a function to enable and set the internal pull
and define its use as needed in the board's variant.h.
Chromium source:
branch: firmware-gnawty-5216.239.B
/src/soc/intel/baytrail/baytrail/gpio.h#418
/src/mainboard/google/gnawty/romstage.c#60
Test: boot 4GB Candy board and observe correct RAM id, amount detected
Change-Id: I8823c27385f4422184b5afa57f6048f7ff2a25ab
Signed-off-by: Matt DeVillier <matt.devillier@gmail.com>
Reviewed-on: https://review.coreboot.org/18309
Tested-by: build bot (Jenkins)
Reviewed-by: Nico Huber <nico.h@gmx.de>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Diffstat (limited to 'src')
5 files changed, 15 insertions, 1 deletions
diff --git a/src/mainboard/google/rambi/romstage.c b/src/mainboard/google/rambi/romstage.c index d8ba001efa..25fe85952b 100644 --- a/src/mainboard/google/rambi/romstage.c +++ b/src/mainboard/google/rambi/romstage.c @@ -32,7 +32,10 @@ static void *get_spd_pointer(char *spd_file_content, int total_spds, int *dual) ssus_disable_internal_pull(GPIO_SSUS_37_PAD); ssus_disable_internal_pull(GPIO_SSUS_38_PAD); ssus_disable_internal_pull(GPIO_SSUS_39_PAD); -#ifdef GPIO_SSUS_40_PAD +#ifdef GPIO_SSUS_40_PAD_USE_PULLDOWN + /* To prevent floating pin on shipped systems. */ + ssus_enable_internal_pull(GPIO_SSUS_40_PAD, PAD_PULL_DOWN | PAD_PU_20K); +#elif defined (GPIO_SSUS_40_PAD) ssus_disable_internal_pull(GPIO_SSUS_40_PAD); #endif ram_id |= (ssus_get_gpio(GPIO_SSUS_37_PAD) << 0); diff --git a/src/mainboard/google/rambi/variants/candy/include/variant/variant.h b/src/mainboard/google/rambi/variants/candy/include/variant/variant.h index 0c58ceefa2..fe4c475825 100644 --- a/src/mainboard/google/rambi/variants/candy/include/variant/variant.h +++ b/src/mainboard/google/rambi/variants/candy/include/variant/variant.h @@ -38,5 +38,6 @@ static const uint32_t dual_channel_config = #define GPIO_SSUS_38_PAD 50 #define GPIO_SSUS_39_PAD 58 #define GPIO_SSUS_40_PAD 52 +#define GPIO_SSUS_40_PAD_USE_PULLDOWN #endif diff --git a/src/mainboard/google/rambi/variants/glimmer/include/variant/variant.h b/src/mainboard/google/rambi/variants/glimmer/include/variant/variant.h index 0ea42c52e9..59d5ee1f6d 100644 --- a/src/mainboard/google/rambi/variants/glimmer/include/variant/variant.h +++ b/src/mainboard/google/rambi/variants/glimmer/include/variant/variant.h @@ -38,5 +38,6 @@ static const uint32_t dual_channel_config = #define GPIO_SSUS_38_PAD 50 #define GPIO_SSUS_39_PAD 58 #define GPIO_SSUS_40_PAD 52 +#define GPIO_SSUS_40_PAD_USE_PULLDOWN #endif diff --git a/src/mainboard/google/rambi/variants/gnawty/include/variant/variant.h b/src/mainboard/google/rambi/variants/gnawty/include/variant/variant.h index 9bac7bc89e..bd79c982ed 100644 --- a/src/mainboard/google/rambi/variants/gnawty/include/variant/variant.h +++ b/src/mainboard/google/rambi/variants/gnawty/include/variant/variant.h @@ -33,5 +33,7 @@ static const uint32_t dual_channel_config = #define GPIO_SSUS_37_PAD 57 #define GPIO_SSUS_38_PAD 50 #define GPIO_SSUS_39_PAD 58 +#define GPIO_SSUS_40_PAD 52 +#define GPIO_SSUS_40_PAD_USE_PULLDOWN #endif diff --git a/src/soc/intel/baytrail/include/soc/gpio.h b/src/soc/intel/baytrail/include/soc/gpio.h index 3757eb012c..9c6b7fd025 100644 --- a/src/soc/intel/baytrail/include/soc/gpio.h +++ b/src/soc/intel/baytrail/include/soc/gpio.h @@ -454,4 +454,11 @@ static inline void ssus_disable_internal_pull(int pad) write32(ssus_pconf0(pad), read32(ssus_pconf0(pad)) & pull_mask); } +static inline void ssus_enable_internal_pull(int pad, int mask) +{ + const int pull_mask = ~(0xf << 7); + write32(ssus_pconf0(pad), + (read32(ssus_pconf0(pad)) & pull_mask) | mask); +} + #endif /* _BAYTRAIL_GPIO_H_ */ |