Commit Graph

8 Commits

Author SHA1 Message Date
James Hogan cec56a733d target/mips: Add segmentation control registers
The optional segmentation control registers CP0_SegCtl0, CP0_SegCtl1 &
CP0_SegCtl2 control the behaviour and required privilege of the legacy
virtual memory segments.

Add them to the CP0 interface so they can be read and written when
CP0_Config3.SC=1, and initialise them to describe the standard legacy
layout so they can be used in future patches regardless of whether they
are exposed to the guest.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Yongbok Kim <yongbok.kim@imgtec.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Yongbok Kim <yongbok.kim@imgtec.com>
Signed-off-by: Yongbok Kim <yongbok.kim@imgtec.com>
2017-07-20 22:42:26 +01:00
James Hogan 42c86612d5 target/mips: Add an MMU mode for ERL
The segmentation control feature allows a legacy memory segment to
become unmapped uncached at error level (according to CP0_Status.ERL),
and in fact the user segment is already treated in this way by QEMU.

Add a new MMU mode for this state so that QEMU's mappings don't persist
between ERL=0 and ERL=1.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Yongbok Kim <yongbok.kim@imgtec.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
[yongbok.kim@imgtec.com:
  cosmetic changes]
Signed-off-by: Yongbok Kim <yongbok.kim@imgtec.com>
2017-07-20 22:42:26 +01:00
James Hogan b0fc600322 target/mips: Abstract mmu_idx from hflags
The MIPS mmu_idx is sometimes calculated from hflags without an env
pointer available as cpu_mmu_index() requires.

Create a common hflags_mmu_index() for the purpose of this calculation
which can operate on any hflags, not just with an env pointer, and
update cpu_mmu_index() itself and gen_intermediate_code() to use it.

Also update debug_post_eret() and helper_mtc0_status() to log the MMU
mode with the status change (SM, UM, or nothing for kernel mode) based
on cpu_mmu_index() rather than directly testing hflags.

This will also allow the logic to be more easily updated when a new MMU
mode is added.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Yongbok Kim <yongbok.kim@imgtec.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Yongbok Kim <yongbok.kim@imgtec.com>
2017-07-20 22:42:26 +01:00
James Hogan 74dbf824a1 target/mips: Add CP0_Ebase.WG (write gate) support
Add support for the CP0_EBase.WG bit, which allows upper bits to be
written (bits 31:30 on MIPS32, or bits 63:30 on MIPS64), along with the
CP0_Config5.CV bit to control whether the exception vector for Cache
Error exceptions is forced into KSeg1.

This is necessary on MIPS32 to support Segmentation Control and Enhanced
Virtual Addressing (EVA) extensions (where KSeg1 addresses may not
represent an unmapped uncached segment).

It is also useful on MIPS64 to allow the exception base to reside in
XKPhys, and possibly out of range of KSEG0 and KSEG1.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Yongbok Kim <yongbok.kim@imgtec.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Yongbok Kim <yongbok.kim@imgtec.com>
[yongbok.kim@imgtec.com:
  minor changes]
Signed-off-by: Yongbok Kim <yongbok.kim@imgtec.com>
2017-07-20 22:42:26 +01:00
Paul Burton bed9e5ceb1 target-mips: Provide function to test if a CPU supports an ISA
Provide a new cpu_supports_isa function which allows callers to
determine whether a CPU supports one of the ISA_ flags, by testing
whether the associated struct mips_def_t sets the ISA flags in its
insn_flags field.

An example use of this is to allow boards which generate bootloader code
to determine the properties of the CPU that will be used, for example
whether the CPU is 64 bit or which architecture revision it implements.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Reviewed-by: Leon Alrae <leon.alrae@imgtec.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Yongbok Kim <yongbok.kim@imgtec.com>
2017-02-21 22:24:58 +00:00
Alex Bennée d10eb08f5d cputlb: drop flush_global flag from tlb_flush
We have never has the concept of global TLB entries which would avoid
the flush so we never actually use this flag. Drop it and make clear
that tlb_flush is the sledge-hammer it has always been.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
[DG: ppc portions]
Acked-by: David Gibson <david@gibson.dropbear.id.au>
2017-01-13 14:24:37 +00:00
Alex Bennée 1f5c00cfdb qom/cpu: move tlb_flush to cpu_common_reset
It is a common thing amongst the various cpu reset functions want to
flush the SoftMMU's TLB entries. This is done either by calling
tlb_flush directly or by way of a general memset of the CPU
structure (sometimes both).

This moves the tlb_flush call to the common reset function and
additionally ensures it is only done for the CONFIG_SOFTMMU case and
when tcg is enabled.

In some target cases we add an empty end_of_reset_fields structure to the
target vCPU structure so have a clear end point for any memset which
is resetting value in the structure before CPU_COMMON (where the TLB
structures are).

While this is a nice clean-up in general it is also a precursor for
changes coming to cputlb for MTTCG where the clearing of entries
can't be done arbitrarily across vCPUs. Currently the cpu_reset
function is usually called from the context of another vCPU as the
architectural power up sequence is run. By using the cputlb API
functions we can ensure the right behaviour in the future.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2017-01-13 14:24:31 +00:00
Thomas Huth fcf5ef2ab5 Move target-* CPU file into a target/ folder
We've currently got 18 architectures in QEMU, and thus 18 target-xxx
folders in the root folder of the QEMU source tree. More architectures
(e.g. RISC-V, AVR) are likely to be included soon, too, so the main
folder of the QEMU sources slowly gets quite overcrowded with the
target-xxx folders.
To disburden the main folder a little bit, let's move the target-xxx
folders into a dedicated target/ folder, so that target-xxx/ simply
becomes target/xxx/ instead.

Acked-by: Laurent Vivier <laurent@vivier.eu> [m68k part]
Acked-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> [tricore part]
Acked-by: Michael Walle <michael@walle.cc> [lm32 part]
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> [s390x part]
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> [s390x part]
Acked-by: Eduardo Habkost <ehabkost@redhat.com> [i386 part]
Acked-by: Artyom Tarasenko <atar4qemu@gmail.com> [sparc part]
Acked-by: Richard Henderson <rth@twiddle.net> [alpha part]
Acked-by: Max Filippov <jcmvbkbc@gmail.com> [xtensa part]
Reviewed-by: David Gibson <david@gibson.dropbear.id.au> [ppc part]
Acked-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com> [cris&microblaze part]
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn> [unicore32 part]
Signed-off-by: Thomas Huth <thuth@redhat.com>
2016-12-20 21:52:12 +01:00