src/mainboard/google/gru/pwm_regulator.c

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 #include <device/mmio.h>
   4 #include <assert.h>
   5 #include <boardid.h>
   6 #include <console/console.h>
   7 #include <gpio.h>
   8 #include <soc/grf.h>
   9 #include <soc/pwm.h>
  10
  11 #include "pwm_regulator.h"
  12
  13 /*
  14  * Apparently a period of 3333 is determined by EEs to be ideal for our
  15  * board design / resistors / capacitors / regulators but due to
  16  * clock dividers we actually get 3337.
  17  */
  18 #define PWM_PERIOD                      3337
  19 #define PWM_DESIGN_VOLTAGE_MIN_OUTDATED 8000
  20 #define PWM_DESIGN_VOLTAGE_MAX_OUTDATED 15000
  21
  22 /* Applies for Kevin rev6+ */
  23 int kevin6_pwm_design_voltage[][2] = {
  24         [PWM_REGULATOR_GPU] = {7858, 12177},
  25         [PWM_REGULATOR_BIG] = {7987, 13022},
  26         [PWM_REGULATOR_LIT] = {7991, 13037},
  27         [PWM_REGULATOR_CENTERLOG] = {8001, 10497}
  28 };
  29
  30 /* Applies for Gru rev2+, Bob, and Nefario. */
  31 int pwm_design_voltage[][2] = {
  32         [PWM_REGULATOR_GPU] = {7864, 12177},
  33         [PWM_REGULATOR_BIG] = {8001, 13022},
  34         [PWM_REGULATOR_LIT] = {7977, 13078},
  35         [PWM_REGULATOR_CENTERLOG] = {7994, 10499}
  36 };
  37
  38 /* Applies for Scarlet-based boards. */
  39 int scarlet_pwm_design_voltage[][2] = {
  40         [PWM_REGULATOR_GPU] = {7996, 10990},
  41         [PWM_REGULATOR_BIG] = {8000, 12992},
  42         [PWM_REGULATOR_LIT] = {8021, 11996},
  43 };
  44
  45 int pwm_enum_to_pwm_number[] = {
  46         [PWM_REGULATOR_GPU] = 0,
  47         [PWM_REGULATOR_LIT] = 2,
  48 #if CONFIG(GRU_HAS_CENTERLOG_PWM)
  49         [PWM_REGULATOR_CENTERLOG] = 3,
  50 #else
  51         [PWM_REGULATOR_CENTERLOG] = -1,
  52 #endif
  53 #if CONFIG(GRU_BASEBOARD_SCARLET)
  54         [PWM_REGULATOR_BIG] = 3,
  55 #else
  56         [PWM_REGULATOR_BIG] = 1,
  57 #endif
  58 };
  59
  60 void pwm_regulator_configure(enum pwm_regulator pwm, int millivolt)
  61 {
  62         int duty_ns, voltage_max, voltage_min;
  63         int voltage = millivolt * 10; /* for higher calculation accuracy */
  64         int pwm_number = pwm_enum_to_pwm_number[pwm];
  65
  66         voltage_min = pwm_design_voltage[pwm][0];
  67         voltage_max = pwm_design_voltage[pwm][1];
  68         if ((CONFIG(BOARD_GOOGLE_KEVIN) && board_id() < 6) ||
  69             (CONFIG(BOARD_GOOGLE_GRU) && board_id() < 2)) {
  70                 voltage_min = PWM_DESIGN_VOLTAGE_MIN_OUTDATED;
  71                 voltage_max = PWM_DESIGN_VOLTAGE_MAX_OUTDATED;
  72         } else if (CONFIG(BOARD_GOOGLE_KEVIN) && board_id() >= 6) {
  73                 voltage_min = kevin6_pwm_design_voltage[pwm][0];
  74                 voltage_max = kevin6_pwm_design_voltage[pwm][1];
  75         } else if (CONFIG(GRU_BASEBOARD_SCARLET)) {
  76                 voltage_min = scarlet_pwm_design_voltage[pwm][0];
  77                 voltage_max = scarlet_pwm_design_voltage[pwm][1];
  78         }
  79
  80         assert(voltage <= voltage_max && voltage >= voltage_min);
  81
  82         /*
  83          * Intentionally round down (higher volt) to be safe.
  84          * eg, for the default min & max design voltage:
  85          *    period = 3337, volt = 1.1: 1906
  86          *    period = 3337, volt = 1.0: 2383
  87          *    period = 3337, volt = 0.9: 2860
  88          */
  89         duty_ns = PWM_PERIOD * (voltage_max - voltage)
  90                              / (voltage_max - voltage_min);
  91
  92         pwm_init(pwm_number, PWM_PERIOD, duty_ns);
  93
  94         switch (pwm_number) {
  95         case 0:
  96                 gpio_input(GPIO(4, C, 2));      /* PWM0 remove pull-down */
  97                 write32(&rk3399_grf->iomux_pwm_0, IOMUX_PWM_0);
  98                 break;
  99         case 1:
 100                 gpio_input(GPIO(4, C, 6));      /* PWM1 remove pull-down */
 101                 write32(&rk3399_grf->iomux_pwm_1, IOMUX_PWM_1);
 102                 break;
 103         case 2:
 104                 gpio_input(GPIO(1, C, 3));      /* PWM2 remove pull-down */
 105                 write32(&rk3399_pmugrf->iomux_pwm_2, IOMUX_PWM_2);
 106                 break;
 107         case 3:
 108                 gpio_input(GPIO(0, A, 6));      /* PWM3 remove pull-down */
 109                 write32(&rk3399_pmugrf->iomux_pwm_3a, IOMUX_PWM_3_A);
 110                 break;
 111         default:
 112                 die("incorrect board configuration");
 113         }
 114 }