These exceptions were new in the Privileged Architecture spec 1.10.
We need to delegate them to S-mode.
Change-Id: Iec15afe9656107b9aeea1677c5b8dc7d654fa746
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-on: https://review.coreboot.org/23774
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Update encoding.h to the version shipped with spike commit
0185d36 ("Merge pull request #165 from riscv/small_progbuf"),
and copy the license header from the LICENSE file.
Change-Id: I517042e5865986e88a589dc8623745f8d584d6b8
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-on: https://review.coreboot.org/23773
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Due to changes in the RISC-V Privileged Architecture specification,
Linux can now be started in physical memory and it will setup its own
page tables.
Thus we can delete most of virtual_memory.c.
Change-Id: I4e69d15f8ee540d2f98c342bc4ec0c00fb48def0
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-on: https://review.coreboot.org/23772
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
This Supervisor Binary Interface, which is based on a page of code
that's provided to operating systems by the M-mode software, has been
superseded by a different (currently not really documented) SBI, which
is based on directly executing ECALLs instructions. Thus some of our
code becomes obsolete. Just rip it out until we implement the new SBI.
Change-Id: Iec9c20b750f39a2b8f1553e25865bbf150605a6d
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-on: https://review.coreboot.org/22593
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
I triggered a bug, when I try to debug riscv code by spike.
This bug is caused by an instruction exception[csrwi 0x320,7].
This is operate for mcounteren. This address is error. 0x306
is right. scounteren is not need to be set, because S-mode
code controls it.
Change-Id: If0bea4bf52d8ad2fb2598724d6feb59dc1b3084a
Signed-off-by: wxjstz<wxjstz@126.com>
Reviewed-on: https://review.coreboot.org/20043
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
The user and supervisor counters could not be safely enabled
before as the register numbers were not finalized. Now that
everyone agrees, we can enable them. Until we are sure the
toolchains are caught up, we use the hardcode name with
the register names in comments. As soon as toolchains
settle down we'll do one more pass and convert to
the symbolic names.
Tested on lowrisc bitstream and SPIKE simulator.
Change-Id: I21fe5cac44fafe4b7806e004c179aa27541be4b6
Signed-off-by: Ronald G. Minnich <rminnich@gmail.com>
Reviewed-on: https://review.coreboot.org/17920
Tested-by: build bot (Jenkins)
Reviewed-by: Alex Bradbury <asb@lowrisc.org>
Reviewed-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-by: Andrew Waterman <aswaterman@gmail.com>
RISCV requires that timer interrupts be handled in machine
mode and delegated as necessary. Also you can only reset the
timer interrupt by writing to mtimecmp. Further, you must
write a number > mtime, not just != mtime. This rather clumsy
situation requires that we write some value into the future
into mtimecmp lest we never be able to leave machine mode as
the interrupt either is not cleared or instantly reoccurs.
This current code is tested and works for harvey (Plan 9)
timer interrupts.
Change-Id: I8538d5fd8d80d9347773c638f5cbf0da18dc1cae
Signed-off-by: Ronald G. Minnich <rminnich@gmail.com>
Reviewed-on: https://review.coreboot.org/17807
Tested-by: build bot (Jenkins)
Reviewed-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
o The first 4G of physical address space is now mapped at 0.
o The first 4G of physical address space is now mapped at 1 << 38.
o The first 2G of DRAM (2 - 4 GiB of physical address space)
is now mapped at the top of memory save for the last 4K
i.e. at 0xffffffff80000000, with SBI page at the very top.
Of these, we hope to remove the *most* of the
last one once the gcc toolchain
can handle linking programs that can run at "top 33 bits
of address not all ones (but bit 63 set)". The 4K mapping
of the top of the 64 bit address space will always remain,
however, for SBI calls.
Change-Id: I77b151720001bddad5563b0f8e1279abcea056fa
Reviewed-on: https://review.coreboot.org/17403
Tested-by: build bot (Jenkins)
Reviewed-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
This variable can be set in a debugger (e.g. Spike)
to finely control which traps go to coreboot and
which go to the supervisor.
Change-Id: I292264c15f002c41cf8d278354d8f4c0efbd0895
Signed-off-by: Ronald G. Minnich <rminnich@gmail.com>
Reviewed-on: https://review.coreboot.org/17404
Tested-by: build bot (Jenkins)
Reviewed-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
This version of coreboot successfully starts a Harvey (Plan 9) kernel as a payload,
entering main() with no supporting assembly code for startup. The Harvey port
is not complete so it just panics but ... it gets started.
We provide a standard payload function that takes a pointer argument
and makes the jump from machine to supervisor mode;
the days of kernels running in machine mode are over.
We do some small tweaks to the virtual memory code. We temporarily
disable two functions that won't work on some targets as register
numbers changed between 1.7 and 1.9. Once lowrisc catches up
we'll reenable them.
We add the PAGETABLES to the memlayout.ld and use _pagetables in the virtual
memory setup code.
We now use the _stack and _estack from memlayout so we know where things are.
As time goes on maybe we can kill all the magic numbers.
Change-Id: I6caadfa9627fa35e31580492be01d4af908d31d9
Signed-off-by: Ronald G. Minnich <rminnich@gmail.com>
Reviewed-on: https://review.coreboot.org/17058
Tested-by: build bot (Jenkins)
Reviewed-by: Furquan Shaikh <furquan@google.com>
Not all SBI calls are implemented, but it's enough to see a couple dozen
lines of Linux boot output.
It should also be noted that the SBI is still in flux:
https://groups.google.com/a/groups.riscv.org/forum/#!topic/sw-dev/6oNhlW0OFKM
Change-Id: I80e4fe508336d6428ca7136bc388fbc3cda4f1e4
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-on: https://review.coreboot.org/16119
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
A new Kconfig option, DEBUG_PRINT_PAGE_TABLES, is added to control this
behaviour. It is currently only available on RISC-V, but other
architectures can use it, too, should the need arise.
Change-Id: I52a863d8bc814ab3ed3a1f141d0a77edc6e4044d
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-on: https://review.coreboot.org/16015
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martinroth@google.com>
In particular:
- Fix the condition of the loop that fills the mid-level page table
- Adhere to the format of sptbr
Change-Id: I575093445edfdf5a8f54b0f8622ff0e89f77ccec
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-on: https://review.coreboot.org/16120
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
I copied it from commit e10d2def7d of spike and made sure the copyright
header is still there.
Change-Id: Ie8b56cd2f4855b97d36a112a195866f4ff0feec5
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-on: https://review.coreboot.org/15832
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
mb() is used in src/arch/riscv/ and src/mainboard/emulation/*-riscv/.
It is currently provided by atomic.h, but I think it fits better into
barrier.h.
The "fence" instruction represents a full memory fence, as opposed to
variants such as "fence r, rw" which represent a partial fence. An
operating system might want to use precisely the right fence, but
coreboot doesn't need this level of performance at the cost of
simplicity.
Change-Id: I8d33ef32ad31e8fda38f6a5183210e7bd6c65815
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-on: https://review.coreboot.org/15830
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
And do the detection just before the initialization.
Change-Id: I9a52430262f799baa298dc4f4ea459880abe250e
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-on: https://review.coreboot.org/15831
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
This function is unused since coreboot starts payloads in machine mode,
and it uses the obsolete eret instruction.
Change-Id: I98d7d0de5a3959821c21a0ba4319efb610fdefde
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-on: https://review.coreboot.org/15729
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
It encourages users from writing to the FSF without giving an address.
Linux also prefers to drop that and their checkpatch.pl (that we
imported) looks out for that.
This is the result of util/scripts/no-fsf-addresses.sh with no further
editing.
Change-Id: Ie96faea295fe001911d77dbc51e9a6789558fbd6
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Reviewed-on: http://review.coreboot.org/11888
Tested-by: build bot (Jenkins)
Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
If we use a linux payload/any payload that wants to manage virtual
memory, and the payload is a supervisor (thus requiring virtual
addressing before being started), we need to make sure that the page
table is mapped into the virtual address space. Move the start address
of the tables so the payload can manage virtual memory.
Change-Id: I1d99e46f38a38a163fb1c7c517b1abca80cde0dc
Signed-off-by: Thaminda Edirisooriya <thaminda@google.com>
Reviewed-on: http://review.coreboot.org/11621
Tested-by: build bot (Jenkins)
Execution in supervisor level code in RISCV requires early setup of
virtual memory. Add initialization calls in
src/arch/riscv/virtual_memory.c to implement the required page table
setup, and helper functions to use when jumping to the payload correctly
in riscv.
Change-Id: I46e080e0ee8dc13277d567dcd4bf0f61a4507b76
Signed-off-by: Thaminda Edirisooriya <thaminda@google.com>
Reviewed-on: http://review.coreboot.org/11369
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
