QEMU-Devel Archive on lore.kernel.org
 help / color / Atom feed
From: Richard Henderson <richard.henderson@linaro.org>
To: Peter Maydell <peter.maydell@linaro.org>,
	qemu-arm@nongnu.org, qemu-devel@nongnu.org
Cc: "Eric Auger" <eric.auger@redhat.com>,
	"Aaron Lindsay" <aaron@os.amperecomputing.com>,
	"Philippe Mathieu-Daudé" <philmd@redhat.com>
Subject: Re: [PATCH v2 10/21] target/arm: Stop assuming DBGDIDR always exists
Date: Fri, 14 Feb 2020 12:15:21 -0800
Message-ID: <4d592ed0-10c3-683b-84d8-cf17a2d491dc@linaro.org> (raw)
In-Reply-To: <20200214175116.9164-11-peter.maydell@linaro.org>

On 2/14/20 9:51 AM, Peter Maydell wrote:
> The AArch32 DBGDIDR defines properties like the number of
> breakpoints, watchpoints and context-matching comparators.  On an
> AArch64 CPU, the register may not even exist if AArch32 is not
> supported at EL1.
> 
> Currently we hard-code use of DBGDIDR to identify the number of
> breakpoints etc; this works for all our TCG CPUs, but will break if
> we ever add an AArch64-only CPU.  We also have an assert() that the
> AArch32 and AArch64 registers match, which currently works only by
> luck for KVM because we don't populate either of these ID registers
> from the KVM vCPU and so they are both zero.
> 
> Clean this up so we have functions for finding the number
> of breakpoints, watchpoints and context comparators which look
> in the appropriate ID register.
> 
> This allows us to drop the "check that AArch64 and AArch32 agree
> on the number of breakpoints etc" asserts:
>  * we no longer look at the AArch32 versions unless that's the
>    right place to be looking
>  * it's valid to have a CPU (eg AArch64-only) where they don't match
>  * we shouldn't have been asserting the validity of ID registers
>    in a codepath used with KVM anyway
> 
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
>  target/arm/cpu.h          |  7 +++++++
>  target/arm/internals.h    | 42 +++++++++++++++++++++++++++++++++++++++
>  target/arm/debug_helper.c |  6 +++---
>  target/arm/helper.c       | 21 +++++---------------
>  4 files changed, 57 insertions(+), 19 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~



  reply index

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-02-14 17:50 [PATCH v2 00/21] arm: ARMv8.1- and v8.4-PMU, ID reg cleanup, [H]ACTLR2 Peter Maydell
2020-02-14 17:50 ` [PATCH v2 01/21] target/arm: Add _aa32_ to isar_feature functions testing 32-bit ID registers Peter Maydell
2020-02-14 17:50 ` [PATCH v2 02/21] target/arm: Check aa32_pan in take_aarch32_exception(), not aa64_pan Peter Maydell
2020-02-14 20:10   ` Richard Henderson
2020-02-14 17:50 ` [PATCH v2 03/21] target/arm: Add isar_feature_any_fp16 and document naming/usage conventions Peter Maydell
2020-02-14 17:50 ` [PATCH v2 04/21] target/arm: Define and use any_predinv isar_feature test Peter Maydell
2020-02-14 17:51 ` [PATCH v2 05/21] target/arm: Factor out PMU register definitions Peter Maydell
2020-02-14 17:51 ` [PATCH v2 06/21] target/arm: Add and use FIELD definitions for ID_AA64DFR0_EL1 Peter Maydell
2020-02-14 17:51 ` [PATCH v2 07/21] target/arm: Use FIELD macros for clearing ID_DFR0 PERFMON field Peter Maydell
2020-02-14 17:51 ` [PATCH v2 08/21] target/arm: Define an aa32_pmu_8_1 isar feature test function Peter Maydell
2020-02-14 17:51 ` [PATCH v2 09/21] target/arm: Add _aa64_ and _any_ versions of pmu_8_1 isar checks Peter Maydell
2020-02-14 17:51 ` [PATCH v2 10/21] target/arm: Stop assuming DBGDIDR always exists Peter Maydell
2020-02-14 20:15   ` Richard Henderson [this message]
2020-02-14 17:51 ` [PATCH v2 11/21] target/arm: Move DBGDIDR into ARMISARegisters Peter Maydell
2020-02-14 20:16   ` Richard Henderson
2020-02-14 17:51 ` [PATCH v2 12/21] target/arm: Read debug-related ID registers from KVM Peter Maydell
2020-02-14 20:27   ` Richard Henderson
2020-02-14 17:51 ` [PATCH v2 13/21] target/arm: Implement ARMv8.1-PMU extension Peter Maydell
2020-02-14 17:51 ` [PATCH v2 14/21] target/arm: Implement ARMv8.4-PMU extension Peter Maydell
2020-02-14 17:51 ` [PATCH v2 15/21] target/arm: Provide ARMv8.4-PMU in '-cpu max' Peter Maydell
2020-02-14 17:51 ` [PATCH v2 16/21] target/arm: Correct definition of PMCRDP Peter Maydell
2020-02-14 17:51 ` [PATCH v2 17/21] target/arm: Correct handling of PMCR_EL0.LC bit Peter Maydell
2020-02-14 17:51 ` [PATCH v2 18/21] target/arm: Test correct register in aa32_pan and aa32_ats1e1 checks Peter Maydell
2020-02-14 20:30   ` Richard Henderson
2020-02-14 17:51 ` [PATCH v2 19/21] target/arm: Use isar_feature function for testing AA32HPD feature Peter Maydell
2020-02-14 20:32   ` Richard Henderson
2020-02-14 17:51 ` [PATCH v2 20/21] target/arm: Use FIELD_EX32 for testing 32-bit fields Peter Maydell
2020-02-14 20:32   ` Richard Henderson
2020-02-14 17:51 ` [PATCH v2 21/21] target/arm: Correctly implement ACTLR2, HACTLR2 Peter Maydell
2020-02-14 20:42   ` Richard Henderson

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=4d592ed0-10c3-683b-84d8-cf17a2d491dc@linaro.org \
    --to=richard.henderson@linaro.org \
    --cc=aaron@os.amperecomputing.com \
    --cc=eric.auger@redhat.com \
    --cc=peter.maydell@linaro.org \
    --cc=philmd@redhat.com \
    --cc=qemu-arm@nongnu.org \
    --cc=qemu-devel@nongnu.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

QEMU-Devel Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/qemu-devel/0 qemu-devel/git/0.git
	git clone --mirror https://lore.kernel.org/qemu-devel/1 qemu-devel/git/1.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 qemu-devel qemu-devel/ https://lore.kernel.org/qemu-devel \
		qemu-devel@nongnu.org
	public-inbox-index qemu-devel

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.nongnu.qemu-devel


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git