From f9d7af17446bb808879c823f4a6129747f78bd29 Mon Sep 17 00:00:00 2001
From: Mark Poliakov <mark@alnyan.me>
Date: Mon, 11 Oct 2021 18:54:36 +0300
Subject: [PATCH] fix: unify boot code

---
 Makefile                               |  2 +-
 etc/aarch64-qemu.ld                    | 10 +++-------
 kernel/src/arch/aarch64/boot/entry.S   |  8 +++++++-
 kernel/src/arch/aarch64/boot/mod.rs    | 14 +++-----------
 kernel/src/arch/aarch64/boot/uboot.S   |  5 -----
 kernel/src/arch/aarch64/exception.rs   |  1 -
 kernel/src/arch/aarch64/irq/gic/mod.rs |  4 ++--
 kernel/src/dev/fdt.rs                  |  1 +
 kernel/src/dev/rtc/pl031.rs            |  2 +-
 9 files changed, 18 insertions(+), 29 deletions(-)

diff --git a/Makefile b/Makefile
index feb5942..467aaea 100644
--- a/Makefile
+++ b/Makefile
@@ -26,7 +26,7 @@ $(error TODO)
 else
 ifeq ($(MACH),qemu)
 QEMU_OPTS+=-kernel $(O)/kernel \
-		   -M virt,virtualization=off \
+		   -M virt,virtualization=on \
 		   -cpu cortex-a72 \
 		   -m 512 \
 		   -serial chardev:serial0 \
diff --git a/etc/aarch64-qemu.ld b/etc/aarch64-qemu.ld
index 2ceb695..0203fcf 100644
--- a/etc/aarch64-qemu.ld
+++ b/etc/aarch64-qemu.ld
@@ -31,18 +31,14 @@ SECTIONS {
     }
 
     . = ALIGN(4K);
-    .tables : AT(. - KERNEL_OFFSET) {
-        *(.tables)
-    }
-
-    . = ALIGN(4K);
+    PROVIDE(__bss_start_phys = . - KERNEL_OFFSET);
+    PROVIDE(__bss_start = .);
     .bss : AT(. - KERNEL_OFFSET) {
-        PROVIDE(__bss_start = .);
         *(COMMON)
         *(.bss*)
         . = ALIGN(4K);
-        PROVIDE(__bss_end = .);
     }
+    PROVIDE(__bss_end_phys = . - KERNEL_OFFSET);
 
     PROVIDE(__kernel_end = .);
 }
diff --git a/kernel/src/arch/aarch64/boot/entry.S b/kernel/src/arch/aarch64/boot/entry.S
index cbd2239..df3f262 100644
--- a/kernel/src/arch/aarch64/boot/entry.S
+++ b/kernel/src/arch/aarch64/boot/entry.S
@@ -13,7 +13,13 @@ _entry:
     b 1b
 
 2:
-    // TODO leave EL2 if running in it
+    mrs x0, currentel
+    cmp x0, #8
+    bne 1f
+
+    b .
+
+1:
 
     // TODO zero .bss
 
diff --git a/kernel/src/arch/aarch64/boot/mod.rs b/kernel/src/arch/aarch64/boot/mod.rs
index 1ec2507..2a16d89 100644
--- a/kernel/src/arch/aarch64/boot/mod.rs
+++ b/kernel/src/arch/aarch64/boot/mod.rs
@@ -4,8 +4,8 @@ use crate::arch::{aarch64::asm::CPACR_EL1, machine};
 use crate::dev::{Device, fdt::DeviceTree};
 use crate::mem::virt;
 use cortex_a::asm::barrier::{self, dsb, isb};
-use cortex_a::registers::{DAIF, SCTLR_EL1, VBAR_EL1, CurrentEL};
-use tock_registers::interfaces::{ReadWriteable, Writeable, Readable};
+use cortex_a::registers::{DAIF, SCTLR_EL1, VBAR_EL1};
+use tock_registers::interfaces::{ReadWriteable, Writeable};
 
 #[no_mangle]
 extern "C" fn __aa64_bsp_main(fdt_base: usize) {
@@ -57,13 +57,5 @@ extern "C" fn __aa64_bsp_main(fdt_base: usize) {
 }
 
 global_asm!(include_str!("macros.S"));
-
-cfg_if! {
-    if #[cfg(feature = "mach_orangepi3")] {
-        global_asm!(include_str!("uboot.S"));
-    } else {
-        global_asm!(include_str!("entry.S"));
-    }
-}
-
+global_asm!(include_str!("uboot.S"));
 global_asm!(include_str!("upper.S"));
diff --git a/kernel/src/arch/aarch64/boot/uboot.S b/kernel/src/arch/aarch64/boot/uboot.S
index 86a960f..10f12d7 100644
--- a/kernel/src/arch/aarch64/boot/uboot.S
+++ b/kernel/src/arch/aarch64/boot/uboot.S
@@ -77,8 +77,3 @@ __aa64_entry_upper:
 bsp_stack_bottom:
     .skip 32768
 bsp_stack_top:
-
-.section .data
-.p2align 4
-fdt_base_phys:
-    .skip 8
diff --git a/kernel/src/arch/aarch64/exception.rs b/kernel/src/arch/aarch64/exception.rs
index 91dcf79..293504f 100644
--- a/kernel/src/arch/aarch64/exception.rs
+++ b/kernel/src/arch/aarch64/exception.rs
@@ -67,7 +67,6 @@ extern "C" fn __aa64_exc_irq_handler() {
 
 #[no_mangle]
 extern "C" fn __aa64_exc_sync_handler(exc: &mut ExceptionFrame) {
-    loop {}
     let err_code = exc.esr >> 26;
     let iss = exc.esr & 0x1FFFFFF;
 
diff --git a/kernel/src/arch/aarch64/irq/gic/mod.rs b/kernel/src/arch/aarch64/irq/gic/mod.rs
index 11fdf74..28211e7 100644
--- a/kernel/src/arch/aarch64/irq/gic/mod.rs
+++ b/kernel/src/arch/aarch64/irq/gic/mod.rs
@@ -57,8 +57,8 @@ impl Device for Gic {
         let gicd_mmio_banked = DeviceMemoryIo::new(gicd_mmio);
         let gicc_mmio = DeviceMemoryIo::map("GICv2 CPU registers", self.gicc_base, 1)?;
 
-        let mut gicd = Gicd::new(gicd_mmio_shared, gicd_mmio_banked);
-        let mut gicc = Gicc::new(gicc_mmio);
+        let gicd = Gicd::new(gicd_mmio_shared, gicd_mmio_banked);
+        let gicc = Gicc::new(gicc_mmio);
 
         gicd.enable();
         gicc.enable();
diff --git a/kernel/src/dev/fdt.rs b/kernel/src/dev/fdt.rs
index 073e7ff..b84854b 100644
--- a/kernel/src/dev/fdt.rs
+++ b/kernel/src/dev/fdt.rs
@@ -14,6 +14,7 @@ static mut INDEX_BUFFER: Wrap = Wrap { data: [0; 65536] };
 
 type INode<'a> = DevTreeIndexNode<'a, 'a, 'a>;
 
+#[allow(dead_code)]
 pub struct DeviceTree {
     tree: DevTree<'static>,
     index: DevTreeIndex<'static, 'static>,
diff --git a/kernel/src/dev/rtc/pl031.rs b/kernel/src/dev/rtc/pl031.rs
index 4e2e902..ad025c0 100644
--- a/kernel/src/dev/rtc/pl031.rs
+++ b/kernel/src/dev/rtc/pl031.rs
@@ -80,7 +80,7 @@ impl Device for Pl031 {
     }
 
     unsafe fn enable(&self) -> Result<(), Errno> {
-        let mut inner = Pl031Inner {
+        let inner = Pl031Inner {
             regs: DeviceMemoryIo::map(self.name(), self.base, 1)?,
         };