Commit Graph

8 Commits

Author SHA1 Message Date
Peter Maydell
27f26bfed9 nvic: Make systick banked
For the v8M security extension, there should be two systick
devices, which use separate banked systick exceptions. The
register interface is banked in the same way as for other
banked registers, including the existence of an NS alias
region for secure code to access the nonsecure timer.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 1512154296-5652-3-git-send-email-peter.maydell@linaro.org
2017-12-13 17:59:26 +00:00
Peter Maydell
e1be0a576b nvic: Implement NVIC_ITNS<n> registers
For v8M, the NVIC has a new set of registers per interrupt,
NVIC_ITNS<n>. These determine whether the interrupt targets Secure
or Non-secure state. Implement the register read/write code for
these, and make them cause NVIC_IABR, NVIC_ICER, NVIC_ISER,
NVIC_ICPR, NVIC_IPR and NVIC_ISPR to RAZ/WI for non-secure
accesses to fields corresponding to interrupts which are
configured to target secure state.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1505240046-11454-8-git-send-email-peter.maydell@linaro.org
2017-09-21 16:29:27 +01:00
Peter Maydell
3b2e934463 nvic: Implement AIRCR changes for v8M
The Application Interrupt and Reset Control Register has some changes
for v8M:
 * new bits SYSRESETREQS, BFHFNMINS and PRIS: these all have
   real state if the security extension is implemented and otherwise
   are constant
 * the PRIGROUP field is banked between security states
 * non-secure code can be blocked from using the SYSRESET bit
   to reset the system if SYSRESETREQS is set

Implement the new state and the changes to register read and write.
For the moment we ignore the effects of the secure PRIGROUP.
We will implement the effects of PRIS and BFHFNMIS later.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1505240046-11454-6-git-send-email-peter.maydell@linaro.org
2017-09-21 16:29:27 +01:00
Peter Maydell
5255fcf8e4 nvic: Add cached vectpending_prio state
Instead of looking up the pending priority
in nvic_pending_prio(), cache it in a new state struct
field. The calculation of the pending priority given
the interrupt number is more complicated in v8M with
the security extension, so the caching will be worthwhile.

This changes nvic_pending_prio() from returning a full
(group + subpriority) priority value to returning a group
priority. This doesn't require changes to its callsites
because we use it only in comparisons of the form
  execution_prio > nvic_pending_prio()
and execution priority is always a group priority, so
a test (exec prio > full prio) is true if and only if
(execprio > group_prio).

(Architecturally the expected comparison is with the
group priority for this sort of "would we preempt" test;
we were only doing a test with a full priority as an
optimisation to avoid the mask, which is possible
precisely because the two comparisons always give the
same answer.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1505240046-11454-5-git-send-email-peter.maydell@linaro.org
2017-09-21 16:29:27 +01:00
Peter Maydell
e93bc2ac11 nvic: Add cached vectpending_is_s_banked state
With banked exceptions, just the exception number in
s->vectpending is no longer sufficient to uniquely identify
the pending exception. Add a vectpending_is_s_banked bool
which is true if the exception is using the sec_vectors[]
array.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1505240046-11454-4-git-send-email-peter.maydell@linaro.org
2017-09-21 16:29:23 +01:00
Peter Maydell
17906a162a nvic: Add banked exception states
For the v8M security extension, some exceptions must be banked
between security states. Add the new vecinfo array which holds
the state for the banked exceptions and migrate it if the
CPU the NVIC is attached to implements the security extension.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2017-09-21 16:28:59 +01:00
Peter Maydell
f104919d15 nvic: Add NS alias SCS region
For v8M the range 0xe002e000..0xe002efff is an alias region which
for secure accesses behaves like a NonSecure access to the main
SCS region. (For nonsecure accesses including when the security
extension is not implemented, it is RAZ/WI.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1503414539-28762-11-git-send-email-peter.maydell@linaro.org
2017-09-07 13:54:53 +01:00
Peter Maydell
d2db1de6ff armv7m_nvic.h: Move from include/hw/arm to include/hw/intc
The armv7m_nvic.h header file was accidentally placed in
include/hw/arm; move it to include/hw/intc to match where
its corresponding .c file lives.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1501692241-23310-15-git-send-email-peter.maydell@linaro.org
2017-09-04 15:21:53 +01:00