diff options
Diffstat (limited to 'src/mainboard')
| -rw-r--r-- | src/mainboard/google/rambi/romstage.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/src/mainboard/google/rambi/romstage.c b/src/mainboard/google/rambi/romstage.c index d15a21dc2d..369ebad445 100644 --- a/src/mainboard/google/rambi/romstage.c +++ b/src/mainboard/google/rambi/romstage.c @@ -37,14 +37,29 @@ #define GPIO_SSUS_38_PAD 50 #define GPIO_SSUS_39_PAD 58 +static inline void disable_internal_pull(int pad) +{ + const int pull_mask = ~(0xf << 7); + write32(ssus_pconf0(pad), read32(ssus_pconf0(pad)) & pull_mask); +} + static void *get_spd_pointer(char *spd_file_content, int total_spds) { int ram_id = 0; + /* The ram_id[2:0] pullups on rambi are too large for the default 20K + * pulldown on the pad. Therefore, disable the internal pull resistor to + * read high values correctly. */ + disable_internal_pull(GPIO_SSUS_37_PAD); + disable_internal_pull(GPIO_SSUS_38_PAD); + disable_internal_pull(GPIO_SSUS_39_PAD); + ram_id |= (ssus_get_gpio(GPIO_SSUS_37_PAD) << 0); ram_id |= (ssus_get_gpio(GPIO_SSUS_38_PAD) << 1); ram_id |= (ssus_get_gpio(GPIO_SSUS_39_PAD) << 2); + printk(BIOS_DEBUG, "ram_id=%d, total_spds: %d\n", ram_id, total_spds); + if (ram_id >= total_spds) return NULL; |