On the RK3399-Q7 "Puma" module VDD_LOG is generated by an external regulator, which sets the voltage level to 900 mV, which is within the allowed range and which works quite fine.
However, in specific use-cases we need to adjust VDD_LOG to maintain stable operation or to reduce power consumption. This adjustment can be done via pwm2.
This patch allows to tune the VDD_LOG voltage level via DTS. To do so the following things are done:
* Setup pin muxing for PWM2 (based on DTS settings) * Turn on the vdd_log regulator (based on DTS settings)
Reported-by: Assaf Agmon assaf@r-go.io Signed-off-by: Philipp Tomsich philipp.tomsich@theobroma-systems.com Signed-off-by: Christoph Muellner christoph.muellner@theobroma-systems.com --- board/theobroma-systems/puma_rk3399/puma-rk3399.c | 43 +++++++++++++++++++++++ 1 file changed, 43 insertions(+)
diff --git a/board/theobroma-systems/puma_rk3399/puma-rk3399.c b/board/theobroma-systems/puma_rk3399/puma-rk3399.c index 573e691457f..e2915fcca50 100644 --- a/board/theobroma-systems/puma_rk3399/puma-rk3399.c +++ b/board/theobroma-systems/puma_rk3399/puma-rk3399.c @@ -23,10 +23,34 @@ #include <power/regulator.h> #include <u-boot/sha256.h>
+static int setup_pinctrl(void) +{ + int ret; + struct udevice *pinctrl; + + ret = uclass_get_device(UCLASS_PINCTRL, 0, &pinctrl); + if (ret) { + debug("%s: Cannot find pinctrl device\n", __func__); + goto out; + } + + /* Enable pwm2 for vdd_log regulator. */ + ret = pinctrl_request_noflags(pinctrl, PERIPH_ID_PWM2); + if (ret) { + printf("%s PWM2 pinctrl init fail!\n", __func__); + goto out; + } + +out: + return 0; +} + int board_init(void) { int ret;
+ setup_pinctrl(); + /* * We need to call into regulators_enable_boot_on() again, as the call * during SPL may have not included all regulators. @@ -35,6 +59,25 @@ int board_init(void) if (ret) debug("%s: Cannot enable boot on regulator\n", __func__);
+ /* + * vdd_log is ignored by regulators_enable_boot_on(), because + * regulator-min-microvolt != regulator-max-microvolt. + * Therefore we explicitly enable it here. + */ + struct udevice *regulator; + ret = regulator_get_by_platname("vdd_log", ®ulator); + if (ret) { + debug("%s Looking up regulator vdd-log failed!\n", __func__); + goto out; + } + + ret = regulator_set_enable(regulator, true); + if (ret) { + debug("%s Enabling vdd-log failed!\n", __func__); + goto out; + } + +out: return 0; }