Since we're using multi-part uImage format, we can add the FDT as
a seperate "blob" in the uImage, if the used U-Boot version is not
"FDT enabled".
This is used for example for our Verdex target. Currently I've got
a local hack in the platform/u-boot/Jamfile, looking into pulling
in the FDT files and a proper Jam setup to do that properly...
This detects everything up to ARMv6 right now. Need to check more
recent ARM ARMs for ARMv7 detection.
The detected details get passed on to the kernel, which can use
the pre-detected info for selecting right pagetable format and such.
Copyright removal of Axel done after agreement with Axel @ BeGeistert
that for files that were copy/pasted from x86 arch and then fully
replaced the implementation, removal of original copyright holder is
allowed, since their actual code is gone ;)
This is to make sure all ARM platforms will benefit from planned work on this
MMU/CPU code. The less code duplicated, the better.
Compile-tested for all supported ARM platforms
This also implements the fault handler correctly now, and cleans up the
exception handling. Seems a lot more stable now, no unexpected panics or
faults happening anymore.
* The only implementation that would accept more than 2 TB was the one in
scsi_disk. But even that one was limited to 63 TB.
* Now there is a new utility function devfs_compute_geometry_size() which
does it correctly for sizes up to 2^64 which should be good enough for
quite some time :-)
* This fixes bug #8992.
* For now let's include the same fields in platform_kernel_args
than in the OF version.
* This allows linking the kernel.
Later on we should allow supporting more than a single boot platform,
to have a single kernel per arch.
The lowest 4 bits of the MSR serves as a hint to the hardware to
favor performance or energy saving. 0 means a hint preference for
highest performance while 15 corresponds to the maximum energy
savings. A value of 7 translates into a hint to balance performance
with energy savings.
The default reset value of the MSR is 0. If BIOS doesn't intialize
the MSR, the hardware will run in performance state. This patch
initialize the MSR with value of 7 for balance between performance
and energy savings
Signed-off-by: Fredrik Holmqvist <fredrik.holmqvist@gmail.com>
Renamed {32,64}/int.cpp to {32,64}/descriptors.cpp, which now contain
functions for GDT and TSS setup that were previously in arch_cpu.cpp,
as well as the IDT setup code. These get called from the init functions
in arch_cpu.cpp, rather than having a bunch of ifdef'd chunks of code
for 32/64.
Reused x86 arch_user_debugger.cpp, with a few minor changes to make
the code work for both 32 and 64 bit. Something isn't quite working
right, if a breakpoint is hit the kernel will hang. Other than that
everything appears to work correctly.
* Changed IS_USER_ADDRESS to check an address using USER_BASE and
USER_SIZE, rather than just !IS_KERNEL_ADDRESS. The old check would
allow user buffers to point into the physical memory map area.
* Added an unmapped hole at the end of the bottom half of the address
space which catches buffers that cross into the uncanonical address
region. This also removes the need to check for uncanonical return
addresses in the syscall handler, it is no longer possible for the
return address to be uncanonical under normal circumstances. All
cases in which the return address might be changed by the kernel
are still handled via the IRET path.
The cookie is used to store the base address of the area that was just
visited. On 64-bit systems, int32 is not sufficient. Therefore, changed
to ssize_t which retains compatibility on x86 while expanding to a
sufficient size on x86_64.
Userland switch is implemented, as is basic system call support (using
SYSCALL/SYSRET). The system call handler is not yet complete: it doesn't
handle more than 6 arguments, and does not perform all the necessary kernel
entry/exit work (neither does the interrupt handler). However, this is
sufficient for runtime_loader to start and print some debug output.
Since this argument may be used to pass pointers, uint32 is not
correct for 64-bit. Effectively no change on 32-bit targets, both
size_t and uint32 are unsigned long there.
No major changes to the kernel: just compiled in arch_smp.cpp and fixed the
IDT load in arch_cpu_init_percpu to use the correct limit for x86_64 (uses
sizeof(interrupt_descriptor)). In the boot loader, changed smp_boot_other_cpus
to construct a temporary GDT and get the page directory address from CR3, as
what's in kernel_args will be 64-bit stuff and will not work to switch the
CPUs into 32-bit mode in the trampoline code. Refactored 64-bit kernel entry
code to not use the stack after disabling paging, as the secondary CPUs are
given a 32-bit virtual stack address by the SMP trampoline code which will
no longer work.
A proper page fault handler was required for areas that were not locked
into the kernel address space. This enables the boot process to get
up to the point of trying to find the boot volume.
* Thread creation and switching is working fine, however threads do not yet
get interrupted because I've not implemented hardware interrupt handling
yet (I'll do that next).
* I've made some changes to struct iframe: I've removed the e/r prefixes
from the member names for both 32/64, so now they're just named ip, ax,
bp, etc. This makes it easier to write code that works with both 32/64
without having to deal with different iframe member names.
This has been done by adding typedefs in elf_common.h to the correct ELF
structures for the architecture, and changing all Elf32_* uses to those
types. I don't know whether image loading works as I cannot test it yet,
there may be some 64-bit safety issues around. However, symbol lookup for
the kernel is working correctly.
* Uses 64-bit multiplication, special handling for CPUs clocked < 1 GHz
in system_time_nsecs() not required like on x86.
* Tested against a straight conversion of the x86 version, noticably
faster with a large number of system_time() calls.
* Added empty source files for all the 64-bit paging method code, and a
stub implementation of X86PagingMethod64Bit.
* arch_vm_translation_map.cpp has been modified to use X86PagingMethod64Bit
on x86_64.
* Some things are currently ifndef'd out completely for x86_64 because
they aren't implemented, there's a few other ifdef's to handle x86_64
differences but most of the code works unchanged.
* Renamed some i386_* functions to x86_*.
* Added a temporary method for setting the current thread on x86_64
(a global variable, not SMP safe). This will be changed to be done
via the GS segment but I've not implemented that yet.
For now I've just put all the stub functions that are needed to link the
kernel into a file called stubs.cpp. I've not yet moved across the interrupt
handling code or the ELF64 relocation code to the x86 directory. Once those
have been moved I can get rid of the x86_64 headers/source directories.
Not many changes seeing as there's not much x86_64 stuff done yet. Small
differences are handled with ifdefs, large differences (descriptors.h,
struct iframe) have separate headers under arch/x86/32 and arch/x86/64.
The setup procedure is fairly simple: create a 64-bit GDT and 64-bit page
tables that include all kernel mappings from the 32-bit address space, but at
the correct 64-bit address, then go through kernel_args and changes all virtual
addresses to 64-bit addresses, and finally switch to long mode and jump to the
kernel.
* platform_allocate_elf_region() is removed, it is implemented in platform-
independent code now (ELF*Class::AllocateRegion). For ELF64 it is now
assumed that 64-bit addresses are mapped in the loader's 32-bit address space
as (address - KERNEL_BASE_64BIT + KERNEL_BASE).
* mapped_delta field from preloaded_*_image removed, now handled compile-time
using the ELF*Class::Map method.
* Also link the kernel with -z max-page-size=0x1000, removes the need for
2MB alignment on the data segment (not going to map the kernel with large
pages for the time being).
The ELF loader now uses a new platform function, platform_allocate_elf_region,
which returns 2 addresses: the real load address and an address where the
region is mapped in the loader's address space. All of the ELF loading code
has been changed to access the load region through the mapped address rather
than the addresses contained in the ELF image. The ELF64 version of
platform_allocate_elf_region on x86 uses the existing MMU code, which maps
everything at 0x80000000, but returns the correct 64-bit address. The long
mode switch code will just set up the 64-bit address space with everything
remapped at the correct address.
* FixedWidthPointer:
- operators ==/!=: Change second operand type from void* to const
Type*. Also add non-const version to resolve ambiguity warning when
comparing with non-const pointer.
- Add Pointer() getter.
- Remove templatized cast operators. They are nice for casting the
pointer directly to another pointer type, but result in ambiguity.
* Make preloaded_image::debug_string_table non-const. Avoids clashes of
the const and non-coast FixedWidthPointer comparison operators. A
cleaner (but more verbose) solution would be to spezialize
FixedWidthPointer for const types.
The actual implementation of the ELF loading methods have been put into
an ELFLoader template class that takes a single template parameter, which
is a structure containing all the necessary ELF typedefs. It's a bit
verbose, but I thought it was a neater solution than using a bunch of
standalone functions with a huge number of template parameters. There is
no change to code outside of elf.cpp, the ELF32/ELF64 differences are
handled internally.
* There is now 2 structures, preloaded_elf32_image and preloaded_elf64_image,
which both inherit from preloaded_image.
* For now I've just hardcoded in use of preloaded_elf32_image, but the
bootloader ELF code will shortly be converted to use templates which use
the appropriate structure. The kernel will be changed later when I add
ELF64 support to it.
* All kernel_args data is now compatible between 32-bit and 64-bit kernels.
* Added a FixedWidthPointer template class which uses 64-bit storage to hold
a pointer. This is used in place of raw pointers in kernel_args.
* Added __attribute__((packed)) to kernel_args and all structures contained
within it. This is necessary due to different alignment behaviour for
32-bit and 64-bit compilation with GCC.
* With these changes, kernel_args will now come out the same size for both
the x86_64 kernel and the loader, excluding the preloaded_image structure
which has not yet been changed.
* Tested both an x86 GCC2 and GCC4 build, no problems caused by these changes.
I've tested this change on x86, causing no issues. I've checked over the code
for all other platforms and made the necessary changes and to the best of my
knowledge they should also still work, but I haven't actually built and
tested them. Once I've completed the kernel_args changes the other platforms
will need testing.
Pointers in kernel_args are going to be changed to unconditionally use 64-bit
storage (to make kernel_args compatible with both the x86 and x86_64 kernels).
KMessage stores a pointer to its buffer, however since KMessage is used
outside of the boot code it is undesirable to change it to use 64-bit storage
for the pointer as it may add additional overhead on 32-bit builds. Therefore,
only store the buffer address and size and then construct a KMessage from
those in the kernel.
The whole kernel now builds and there are no undefined references when
linking, I just need to fix some strange relocation errors I'm getting
(probably a problem with the linker script) and then I'll have a kernel
image.
Since ICI arguments are used to send addresses in some places, uint32 is
not sufficient on x86_64. addr_t still refers to the same type as uint32
(unsigned long) on other platforms, so this change only really affects
x86_64.
* x86_64 is using the existing *_ia32 boot platforms.
* Special flags are required when compiling the loader to get GCC to compile
32-bit code. This adds a new set of rules for compiling boot code rather
than using the kernel rules, which compile using the necessary flags.
* Some x86_64 private headers have been stubbed by #include'ing the x86
versions. These will be replaced later.
* gPeripheralBase keeps track of the device
peripherals before and after mmu_init
* Add ability to disable mmu for troubleshooting
* Remove static FB_BASE, we actually don't know
where the FB is yet. (depends on firmware used)
* BCM2708 defines no longer assume 0x20 address
We will be throwing away the blob memory mapping
and using our own.
* Use existing blob mapping to turn GPIO led on pre mmu_init
* Remap MMU hardware addresses from 0x7E. We could map each device,
however the kernel will throw away the mappings again anyway. For
now we just map the whole range and use offsets.
* Serial uart no longer works, however at least
we know why now :). Serial driver now needs to
use mapped address.
* Use U-Boot mmu code as base
* This will be factored out someday into common arch mmu
code when we can read Flattened Device Trees
* Move mmu_init after serial_init.
Temporary change as we will want serial_init to use
memory mapped addresses... for debugging.
* introduce a DebugUART baseclass,
* rework 8250 and PL011 implementations from kallisti5 to inherit DebutUART,
* each arch should override the IO methods to access registers.
* on ARM registers are 32bit-aligned.
* U-Boot still works for the verdex target.
* rPi still compiles, needs testing.
* Still some more consolidation needed to allow runtime choice of the UART type (as read from FDT blobs for ex.).
* serial.cpp should probably mostly be made generic as well.
* didn't touch x86 or ppc yet.
* Enable/Disable makes more sense and matches
platform loader serial functions.
* Rework PL011 code after finding a PDF covering
the details of it.
* Rename UART global defines in loader to be more
exact about location
* This makes things a little more flexible and
the interface to use the uarts cleaner.
* May want to make a generic Uart wrapper
class in uart.h / uart.cpp and call drivers
as needed from there.
* Avoid name collisions
* This uart stuff may work better as a class at
some point, however I didn't want to rock the
u-boot boat *too* much as I don't have the
hardware to test.
* Add nested function wrappers to allow usage of other
uart drivers depending on board. We may want to use this
on other platforms at some point (haha, maybe)
* Make Kernel ARM UART slightly more generic
through (BOARD_UART_CLOCK) configured per board
* Add initial Raspberry Pi serial code
* Still rough and non-working
