* 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)
