In the tz-mpc device we allocate a data block for the LUT,
which we then clear to zero in the device's reset method.
This is conceptually fine, but unfortunately results in a
valgrind complaint about use of uninitialized data on startup:
==30906== Conditional jump or move depends on uninitialised value(s)
==30906== at 0x503609: tz_mpc_translate (tz-mpc.c:439)
==30906== by 0x3F3D90: address_space_translate_iommu (exec.c:511)
==30906== by 0x3F3FF8: flatview_do_translate (exec.c:584)
==30906== by 0x3F4292: flatview_translate (exec.c:644)
==30906== by 0x3F2120: address_space_translate (memory.h:1962)
==30906== by 0x3FB753: address_space_ldl_internal (memory_ldst.inc.c:36)
==30906== by 0x3FB8A6: address_space_ldl (memory_ldst.inc.c:80)
==30906== by 0x619037: ldl_phys (memory_ldst_phys.inc.h:25)
==30906== by 0x61985D: arm_cpu_reset (cpu.c:255)
==30906== by 0x98791B: cpu_reset (cpu.c:249)
==30906== by 0x57FFDB: armv7m_reset (armv7m.c:265)
==30906== by 0x7B1775: qemu_devices_reset (reset.c:69)
This is because of a reset ordering problem -- the TZ MPC
resets after the CPU, but an M-profile CPU's reset function
includes memory loads to get the initial PC and SP, which
then go through an MPC that hasn't yet been reset.
The simplest fix for this is to zero the LUT when we
initialize the data, which will result in the MPC's
translate function giving the right answers for these
early memory accesses.
Reported-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Thomas Huth <thuth@redhat.com>
Message-id: 20180724153616.32352-1-peter.maydell@linaro.org
The final part of the Memory Protection Controller we need to
implement is actually using the BLK_LUT data programmed by the
guest to determine whether to block the transaction or not.
Since this means we now change transaction mappings when
the guest writes to BLK_LUT, we must also call the IOMMU
notifiers at that point.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Message-id: 20180620132032.28865-5-peter.maydell@linaro.org
The MPC is guest-configurable for whether blocked accesses:
* should be RAZ/WI or cause a bus error
* should generate an interrupt or not
Implement this behaviour in the blocked-access handlers.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Message-id: 20180620132032.28865-4-peter.maydell@linaro.org
Implement the missing registers for the TZ MPC.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Message-id: 20180620132032.28865-3-peter.maydell@linaro.org
Implement the Arm TrustZone Memory Protection Controller, which sits
in front of RAM and allows secure software to configure it to either
pass through or reject transactions.
We implement the MPC as a QEMU IOMMU, which will direct transactions
either through to the devices and memory behind it or to a special
"never works" AddressSpace if they are blocked.
This initial commit implements the skeleton of the device:
* it always permits accesses
* it doesn't implement most of the registers
* it doesn't implement the interrupt or other behaviour
for blocked transactions
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Message-id: 20180620132032.28865-2-peter.maydell@linaro.org
Peter Maydell