From 69eae2762fc34f8303e8a41065df437295262586 Mon Sep 17 00:00:00 2001 From: Hung-Te Lin Date: Thu, 18 Apr 2019 17:31:55 +0800 Subject: [PATCH] board/kukui: Support ADC value for NC When the components like LCM ID are not installed (i.e., NC), ADC will return some value with much larger variation from standard value (out of the tolerance we set). To support that, we should check tolerance only on non-NC voltages. Also improve the error messages so we can see the ADC raw values instead of simple assertion error (which makes debugging more difficult since we have to build another firmware image just to print the values). BUG=None TEST=Booted on Kukui and got correct SKU ID for NC LCMID. BRANCH=None Change-Id: I8d00956e0e3b48ddbcaa505dd3ade24720c3b4ad Signed-off-by: Hung-Te Lin Reviewed-on: https://review.coreboot.org/c/coreboot/+/32353 Reviewed-by: Julius Werner Reviewed-by: You-Cheng Syu Tested-by: build bot (Jenkins) --- src/mainboard/google/kukui/boardid.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/src/mainboard/google/kukui/boardid.c b/src/mainboard/google/kukui/boardid.c index b9f1ba2226..71f051f312 100644 --- a/src/mainboard/google/kukui/boardid.c +++ b/src/mainboard/google/kukui/boardid.c @@ -15,6 +15,7 @@ #include #include +#include #include #include #include @@ -82,8 +83,13 @@ static uint32_t get_adc_index(unsigned int channel) if (value < (voltages[id] + voltages[id + 1]) / 2) break; + /* The last level is NC and may be larger than standard tolerance. */ const int tolerance = 10000; /* 10,000 uV */ - assert(ABS(value - voltages[id]) < tolerance); + if (id < ADC_LEVELS - 1 && ABS(value - voltages[id]) > tolerance) { + printk(BIOS_ERR, "ADC channel %u value out of range: %d\n", + channel, value); + assert(0); + } return id; }