src/mainboard/google/cherry/boardid.c

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 #include <assert.h>
   4 #include <boardid.h>
   5 #include <console/console.h>
   6 #include <ec/google/chromeec/ec.h>
   7 #include <soc/auxadc.h>
   8
   9 /* board_id is provided by ec/google/chromeec/ec_boardid.c */
  10
  11 #define ADC_LEVELS 12
  12
  13 enum {
  14         /* RAM IDs */
  15         RAM_ID_LOW_CHANNEL = 2,
  16         RAM_ID_HIGH_CHANNEL = 3,
  17         /* SKU IDs */
  18         SKU_ID_LOW_CHANNEL = 4,
  19         SKU_ID_HIGH_CHANNEL = 5,
  20 };
  21
  22 static const unsigned int ram_voltages[ADC_LEVELS] = {
  23         /* ID : Voltage (unit: uV) */
  24         [0]  =   74300,
  25         [1]  =  211700,
  26         [2]  =  318800,
  27         [3]  =  428600,
  28         [4]  =  541700,
  29         [5]  =  665800,
  30         [6]  =  781400,
  31         [7]  =  900000,
  32         [8]  = 1023100,
  33         [9]  = 1137000,
  34         [10] = 1240000,
  35         [11] = 1342600,
  36 };
  37
  38 static const unsigned int *adc_voltages[] = {
  39         [RAM_ID_LOW_CHANNEL] = ram_voltages,
  40         [RAM_ID_HIGH_CHANNEL] = ram_voltages,
  41         [SKU_ID_LOW_CHANNEL] = ram_voltages,
  42         [SKU_ID_HIGH_CHANNEL] = ram_voltages,
  43 };
  44
  45 static uint32_t get_adc_index(unsigned int channel)
  46 {
  47         unsigned int value = auxadc_get_voltage_uv(channel);
  48
  49         assert(channel < ARRAY_SIZE(adc_voltages));
  50         const unsigned int *voltages = adc_voltages[channel];
  51         assert(voltages);
  52
  53         /* Find the closest voltage */
  54         uint32_t id;
  55         for (id = 0; id < ADC_LEVELS - 1; id++)
  56                 if (value < (voltages[id] + voltages[id + 1]) / 2)
  57                         break;
  58
  59         printk(BIOS_DEBUG, "ADC[%u]: Raw value=%u ID=%u\n", channel, value, id);
  60         return id;
  61 }
  62
  63 uint32_t sku_id(void)
  64 {
  65         static uint32_t cached_sku_code = BOARD_ID_INIT;
  66
  67         if (cached_sku_code == BOARD_ID_INIT) {
  68                 cached_sku_code = google_chromeec_get_board_sku();
  69
  70                 if (cached_sku_code == CROS_SKU_UNKNOWN) {
  71                         printk(BIOS_WARNING, "Failed to get SKU code from EC\n");
  72                         cached_sku_code = (get_adc_index(SKU_ID_HIGH_CHANNEL) << 4 |
  73                                            get_adc_index(SKU_ID_LOW_CHANNEL));
  74                 }
  75                 printk(BIOS_DEBUG, "SKU Code: %#02x\n", cached_sku_code);
  76         }
  77
  78         return cached_sku_code;
  79 }
  80
  81 uint32_t ram_code(void)
  82 {
  83         static uint32_t cached_ram_code = BOARD_ID_INIT;
  84
  85         if (cached_ram_code == BOARD_ID_INIT) {
  86                 cached_ram_code = (get_adc_index(RAM_ID_HIGH_CHANNEL) << 4 |
  87                                    get_adc_index(RAM_ID_LOW_CHANNEL));
  88                 printk(BIOS_DEBUG, "RAM Code: %#02x\n", cached_ram_code);
  89         }
  90
  91         return cached_ram_code;
  92 }