Hung-Te Lin has submitted this change. ( https://review.coreboot.org/c/coreboot/+/46391 )
Change subject: mb/google/asurada: Get RAM code from ADC 3 ......................................................................
mb/google/asurada: Get RAM code from ADC 3
On Chromebooks the RAM code is implemented by the resistor straps that we can read and decode from ADC. For Asurada the RAM code can be read from ADC channel 3.
Signed-off-by: CK Hu ck.hu@mediatek.com Signed-off-by: Yidi Lin yidi.lin@mediatek.com Change-Id: Iaadabea1b6aa91c48b137f7c6784ab7ee0adc473 Reviewed-on: https://review.coreboot.org/c/coreboot/+/46391 Tested-by: build bot (Jenkins) no-reply@coreboot.org Reviewed-by: Hung-Te Lin hungte@chromium.org Reviewed-by: Angel Pons th3fanbus@gmail.com --- M src/mainboard/google/asurada/boardid.c 1 file changed, 56 insertions(+), 1 deletion(-)
Approvals: build bot (Jenkins): Verified Angel Pons: Looks good to me, approved Hung-Te Lin: Looks good to me, approved
diff --git a/src/mainboard/google/asurada/boardid.c b/src/mainboard/google/asurada/boardid.c index 2c8efcd..cb91812 100644 --- a/src/mainboard/google/asurada/boardid.c +++ b/src/mainboard/google/asurada/boardid.c @@ -1,9 +1,59 @@ /* SPDX-License-Identifier: GPL-2.0-only */
+#include <assert.h> #include <boardid.h> +#include <console/console.h> +#include <soc/auxadc.h>
/* board_id is provided by ec/google/chromeec/ec_boardid.c */
+#define ADC_LEVELS 15 + +enum { + RAM_ID_CHANNEL = 3, +}; + +static const unsigned int ram_voltages[ADC_LEVELS] = { + /* ID : Voltage (unit: uV) */ + [0] = 74300, + [1] = 211700, + [2] = 318800, + [3] = 428600, + [4] = 541700, + [5] = 665800, + [6] = 781400, + [7] = 900000, + [8] = 1023100, + [9] = 1137000, + [10] = 1240000, + [11] = 1342600, + [12] = 1457500, + [13] = 1575600, + [14] = 1683600, +}; + +static const unsigned int *adc_voltages[] = { + [RAM_ID_CHANNEL] = ram_voltages, +}; + +static uint32_t get_adc_index(unsigned int channel) +{ + unsigned int value = auxadc_get_voltage_uv(channel); + + assert(channel < ARRAY_SIZE(adc_voltages)); + const unsigned int *voltages = adc_voltages[channel]; + assert(voltages); + + /* Find the closest voltage */ + uint32_t id; + for (id = 0; id < ADC_LEVELS - 1; id++) + if (value < (voltages[id] + voltages[id + 1]) / 2) + break; + + printk(BIOS_DEBUG, "ADC[%u]: Raw value=%u ID=%u\n", channel, value, id); + return id; +} + uint32_t sku_id(void) { return 0; @@ -11,5 +61,10 @@
uint32_t ram_code(void) { - return 0; + static uint32_t cached_ram_code = BOARD_ID_INIT; + + if (cached_ram_code == BOARD_ID_INIT) + cached_ram_code = get_adc_index(RAM_ID_CHANNEL); + + return cached_ram_code; }