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Firmware: frequency multipler for WRPLL

si549: add bit bang mmcm dynamic configuration
si549: add 125Mhz wrpll refclk setup
This commit is contained in:
morgan 2024-05-24 11:15:22 +08:00 committed by Sébastien Bourdeauducq
parent c5147d7744
commit 44cfacf2c4
1 changed files with 140 additions and 0 deletions

View File

@ -720,3 +720,143 @@ pub mod wrpll {
}
}
#[cfg(has_wrpll_refclk)]
pub mod wrpll_refclk {
use super::*;
pub struct MmcmSetting {
pub clkout0_reg1: u16, //0x08
pub clkout0_reg2: u16, //0x09
pub clkfbout_reg1: u16, //0x14
pub clkfbout_reg2: u16, //0x15
pub div_reg: u16, //0x16
pub lock_reg1: u16, //0x18
pub lock_reg2: u16, //0x19
pub lock_reg3: u16, //0x1A
pub power_reg: u16, //0x28
pub filt_reg1: u16, //0x4E
pub filt_reg2: u16, //0x4F
}
fn one_clock_cycle() {
unsafe {
csr::wrpll_refclk::mmcm_dclk_write(1);
csr::wrpll_refclk::mmcm_dclk_write(0);
}
}
fn set_addr(address: u8) {
unsafe {
csr::wrpll_refclk::mmcm_daddr_write(address);
}
}
fn set_data(value: u16) {
unsafe {
csr::wrpll_refclk::mmcm_din_write(value);
}
}
fn set_enable(en: bool) {
let val = if en { 1 } else { 0 };
unsafe {
csr::wrpll_refclk::mmcm_den_write(val);
}
}
fn set_write_enable(en: bool) {
let val = if en { 1 } else { 0 };
unsafe {
csr::wrpll_refclk::mmcm_dwen_write(val);
}
}
fn get_data() -> u16 {
unsafe { csr::wrpll_refclk::mmcm_dout_read() }
}
fn drp_ready() -> bool {
unsafe { csr::wrpll_refclk::mmcm_dready_read() == 1 }
}
#[allow(dead_code)]
fn read(address: u8) -> u16 {
set_addr(address);
set_enable(true);
// Set DADDR on the mmcm and assert DEN for one clock cycle
one_clock_cycle();
set_enable(false);
while !drp_ready() {
// keep the clock signal until data is ready
one_clock_cycle();
}
get_data()
}
fn write(address: u8, value: u16) {
set_addr(address);
set_data(value);
set_write_enable(true);
set_enable(true);
// Set DADDR, DI on the mmcm and assert DWE, DEN for one clock cycle
one_clock_cycle();
set_write_enable(false);
set_enable(false);
while !drp_ready() {
// keep the clock signal until write is finished
one_clock_cycle();
}
}
fn reset(rst: bool) {
let val = if rst { 1 } else { 0 };
unsafe {
csr::wrpll_refclk::mmcm_reset_write(val)
}
}
pub fn setup(settings: MmcmSetting, mmcm_bypass: bool) -> Result<(), &'static str> {
unsafe {
csr::wrpll_refclk::refclk_reset_write(1);
}
if mmcm_bypass {
info!("Bypassing mmcm");
unsafe {
csr::wrpll_refclk::mmcm_bypass_write(1);
}
} else {
// Based on "DRP State Machine" from XAPP888
// hold reset HIGH during mmcm config
reset(true);
write(0x08, settings.clkout0_reg1);
write(0x09, settings.clkout0_reg2);
write(0x14, settings.clkfbout_reg1);
write(0x15, settings.clkfbout_reg2);
write(0x16, settings.div_reg);
write(0x18, settings.lock_reg1);
write(0x19, settings.lock_reg2);
write(0x1A, settings.lock_reg3);
write(0x28, settings.power_reg);
write(0x4E, settings.filt_reg1);
write(0x4F, settings.filt_reg2);
reset(false);
// wait for the mmcm to lock
clock::spin_us(100);
let locked = unsafe { csr::wrpll_refclk::mmcm_locked_read() == 1 };
if !locked {
return Err("mmcm failed to generate 125MHz ref clock from SMA CLKIN");
}
}
unsafe {
csr::wrpll_refclk::refclk_reset_write(0);
}
Ok(())
}
}