use r0::zero_bss; use libregister::{ VolatileCell, RegisterR, RegisterW, RegisterRW, }; use libcortex_a9::{asm, regs::*, cache, mmu}; use libboard_zynq::{slcr, mpcore}; extern "C" { static mut __bss_start: u32; static mut __bss_end: u32; static mut __stack_start: u32; fn main_core0(); fn main_core1(); } /// `0` means: wait for initialization by core0 static mut CORE1_STACK: VolatileCell = VolatileCell::new(0); #[link_section = ".text.boot"] #[no_mangle] #[naked] pub unsafe extern "C" fn _boot_cores() -> ! { const CORE_MASK: u32 = 0x3; match MPIDR.read() & CORE_MASK { 0 => { SP.write(&mut __stack_start as *mut _ as u32); boot_core0(); } 1 => { while CORE1_STACK.get() == 0 { asm::wfe(); } SP.write(CORE1_STACK.get()); boot_core1(); } _ => unreachable!(), } } #[naked] #[inline(never)] unsafe fn boot_core0() -> ! { l1_cache_init(); let mpcore = mpcore::RegisterBlock::new(); mpcore.scu_invalidate.invalidate_all_cores(); zero_bss(&mut __bss_start, &mut __bss_end); let mmu_table = mmu::L1Table::get() .setup_flat_layout(); mmu::with_mmu(mmu_table, || { mpcore.scu_control.start(); ACTLR.enable_smp(); // TODO: Barriers reqd when core1 is not yet starting? asm::dmb(); asm::dsb(); main_core0(); panic!("return from main"); }); } #[naked] #[inline(never)] unsafe fn boot_core1() -> ! { l1_cache_init(); let mpcore = mpcore::RegisterBlock::new(); mpcore.scu_invalidate.invalidate_core1(); let mmu_table = mmu::L1Table::get(); mmu::with_mmu(mmu_table, || { ACTLR.enable_smp(); // TODO: Barriers reqd when core1 is not yet starting? asm::dmb(); asm::dsb(); main_core1(); panic!("return from main_core1"); }); } fn l1_cache_init() { use libcortex_a9::cache::*; // Invalidate TLBs tlbiall(); // Invalidate I-Cache iciallu(); // Invalidate Branch Predictor Array bpiall(); // Invalidate D-Cache // // NOTE: It is both faster and correct to only invalidate instead // of also flush the cache (as was done before with // `dccisw()`) and it is correct to perform this operation // for all of the L1 data cache rather than a (previously // unspecified) combination of one cache set and one cache // way. dciall(); } pub struct Core1> { pub stack: S, } impl> Core1 { pub fn stop(&self) { slcr::RegisterBlock::unlocked(|slcr| { slcr.a9_cpu_rst_ctrl.modify(|_, w| w.a9_rst1(true)); slcr.a9_cpu_rst_ctrl.modify(|_, w| w.a9_clkstop1(true)); slcr.a9_cpu_rst_ctrl.modify(|_, w| w.a9_rst1(false)); }); } /// Reset and start core1 /// /// The stack must not be in OCM because core1 still has to /// initialize its MMU before it can access DDR. pub fn start(stack: S) -> Self { let mut core = Core1 { stack }; // reset and stop (safe to repeat) core.stop(); let stack = core.stack.as_mut(); let stack_start = &mut stack[stack.len() - 1]; unsafe { CORE1_STACK.set(stack_start as *mut _ as u32); } // Ensure stack pointer has been written to cache asm::dmb(); // Flush cache-line cache::dccmvac(unsafe { &CORE1_STACK } as *const _ as u32); // wake up core1 slcr::RegisterBlock::unlocked(|slcr| { slcr.a9_cpu_rst_ctrl.modify(|_, w| w.a9_rst1(false)); slcr.a9_cpu_rst_ctrl.modify(|_, w| w.a9_clkstop1(false)); }); core } }