use libregister::{RegisterR, RegisterRW}; use super::slcr; pub use slcr::ArmPllSource; pub mod source; use source::*; enum CpuClockMode { /// Clocks run in 4:2:2:1 mode C421, /// Clocks run in 6:3:2:1 mode C621, } impl CpuClockMode { pub fn get() -> Self { let regs = slcr::RegisterBlock::new(); if regs.clk_621_true.read().clk_621_true() { CpuClockMode::C621 } else { CpuClockMode::C421 } } } #[derive(Debug, Clone)] pub struct Clocks { /// ARM PLL: Recommended clock source for the CPUs and the interconnect pub arm: u32, /// DDR PLL: Recommended clock for the DDR DRAM controller and AXI_HP interfaces pub ddr: u32, /// I/O PLL: Recommended clock for I/O peripherals pub io: u32, } impl Clocks { pub fn get() -> Self { Clocks { arm: ArmPll::freq(), ddr: DdrPll::freq(), io: IoPll::freq(), } } pub fn set_cpu_freq(target_freq: u32) { let arm_pll = ArmPll::freq(); // 1 and 3 cannot be used let mut div = 2u8; while div == 3 || (div < 63 && arm_pll / u32::from(div) > target_freq) { div += 1; } slcr::RegisterBlock::unlocked(|slcr| { slcr.arm_clk_ctrl.modify(|_, w| w .srcsel(ArmPllSource::ArmPll) .divisor(div) ); }) } pub fn cpu_6x4x(&self) -> u32 { let slcr = slcr::RegisterBlock::new(); let arm_clk_ctrl = slcr.arm_clk_ctrl.read(); let pll = match arm_clk_ctrl.srcsel() { ArmPllSource::ArmPll => self.arm, ArmPllSource::DdrPll => self.ddr, ArmPllSource::IoPll => self.io, }; pll / u32::from(arm_clk_ctrl.divisor()) } pub fn cpu_3x2x(&self) -> u32 { self.cpu_6x4x() / 2 } pub fn cpu_2x(&self) -> u32 { match CpuClockMode::get() { CpuClockMode::C421 => self.cpu_6x4x() / 2, CpuClockMode::C621 => self.cpu_6x4x() / 3, } } pub fn cpu_1x(&self) -> u32 { match CpuClockMode::get() { CpuClockMode::C421 => self.cpu_6x4x() / 4, CpuClockMode::C621 => self.cpu_6x4x() / 6, } } pub fn uart_ref_clk(&self) -> u32 { let regs = slcr::RegisterBlock::new(); let uart_clk_ctrl = regs.uart_clk_ctrl.read(); let pll = match uart_clk_ctrl.srcsel() { slcr::PllSource::ArmPll => self.arm, slcr::PllSource::DdrPll => self.ddr, slcr::PllSource::IoPll => self.io, }; pll / u32::from(uart_clk_ctrl.divisor()) } }