Changeset a4bd537 in mainline for boot/Makefile.grub

Timestamp:

2019-04-06T13:39:58Z (6 years ago)

Author:

Petr Pavlu <setup@…>

Children:

f7842ef

Parents:

0d073b8

git-author:

Petr Pavlu <setup@…> (2019-03-31 14:09:57)

git-committer:

Petr Pavlu <setup@…> (2019-04-06 13:39:58)

Message:

arm64: Add support for the architecture

This changeset adds basic support to run HelenOS on AArch64, targeting
the QEMU virt platform.

Boot:

• Boot relies on the EDK II firmware, GRUB2 for EFI and the HelenOS bootloader (UEFI application). EDK II loads GRUB2 from a CD, GRUB2 loads the HelenOS bootloader (via UEFI) which loads OS components.
• UEFI applications use the PE/COFF format and must be relocatable. The first problem is solved by manually having the PE/COFF headers and tables written in assembler. The relocatable requirement is addressed by compiling the code with -fpic and having the bootloader relocate itself at its startup.

Kernel:

• Kernel code for AArch64 consists mostly of stubbing out various architecture-specific hooks: virtual memory management, interrupt and exception handling, context switching (including FPU lazy switching), support for virtual timer, atomic sequences and barriers, cache and TLB maintenance, thread and process initialization.
• The patch adds a kernel driver for GICv2 (interrupt controller).
• The PL011 kernel driver is extended to allow userspace to take ownership of the console.
• The current code is not able to dynamically obtain information about available devices on the underlying machine. The port instead implements a machine-func interface similar to the one implemented by arm32. It defines a machine for the QEMU AArch64 virt platform. The configuration (device addresses and IRQ numbers) is then baked into the machine definition.

User space:

• Uspace code for AArch64 similarly mostly implements architecture-specific hooks: context saving/restoring, syscall support, TLS support.

The patchset allows to boot the system but user interaction with the OS
is not yet possible.

File:

• boot/Makefile.grub (modified) (3 diffs)

boot/Makefile.grub

@@ -64 +64 @@
 endif
 
+ifeq ($(GRUB_LOADER),multiboot)
         for module in $(COMPONENTS) ; do \
                 cp "$$module" $(BOOT)/ ; \
         done
+endif
+ifeq ($(GRUB_LOADER),chainloader)
+        cp "$(BOOT_OUTPUT)" $(BOOT)/
+endif
 
         echo "set default=0" > $(BOOT_CONFIG)
@@ -83 +88 @@
 
         echo "menuentry 'HelenOS $(RELEASE)' --class helenos --class os {" >> $(BOOT_CONFIG)
+ifeq ($(GRUB_LOADER),multiboot)
         for module in $(MODULES) ; do \
                 echo "  echo 'Loading $$module'" >> $(BOOT_CONFIG) ; \
@@ -91 +97 @@
                 fi \
         done
+endif
+ifeq ($(GRUB_LOADER),chainloader)
+        echo "  echo 'Loading $(BOOT_OUTPUT)'" >> $(BOOT_CONFIG)
+        echo "  chainloader /boot/$(BOOT_OUTPUT)" >> $(BOOT_CONFIG)
+        echo "  boot" >> $(BOOT_CONFIG)
+endif
         echo "}" >> $(BOOT_CONFIG)