From: Wolfram Sang <wsa+renesas@sang-engineering.com>
To: linux-kernel@vger.kernel.org
Cc: linux-renesas-soc@vger.kernel.org, linux-gpio@vger.kernel.org,
Wolfram Sang <wsa+renesas@sang-engineering.com>
Subject: [PATCH RFC/RFT 0/1] add simple logic analyzer using polling
Date: Tue, 30 Mar 2021 10:56:54 +0200 [thread overview]
Message-ID: <20210330085655.12615-1-wsa+renesas@sang-engineering.com> (raw)
Okay, this one is maybe a bit brave, let's see if it is suitable for
upstream. This is an in-kernel logic analyzer based on GPIO polling with
local irqs disabled. Besides the driver, there is a script which
isolates a CPU to get towards the best possible result. I am aware of
the latency limitations. However, the intention is only for debugging.
Especially for remote debugging and to get a first impression, this has
already been useful. So, I wonder if we want to provide this for others,
too, and have it in Linus' tree. Documentation is within the patch, to
get a better idea what this is all about.
A branch with preparation for the Renesas Salvator-XS boards is here:
git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux.git renesas/topic/gpio-logic-analyzer
The documentation is also available online on the elinux wiki:
https://elinux.org/Kernel_GPIO_Logic_analyzer
Looking forward to comments. If somebody has a pointer how to detect if
a task was requested to be killed (while irqs and preemption are
disabled), I'd appreciate that to avoid the currently unkillable
sub-process.
All the best,
Wolfram
Wolfram Sang (1):
misc: add simple logic analyzer using polling
.../dev-tools/gpio-logic-analyzer.rst | 63 ++++
Documentation/dev-tools/index.rst | 1 +
.../bindings/misc/gpio-logic-analyzer.yaml | 40 ++
drivers/misc/Kconfig | 12 +
drivers/misc/Makefile | 1 +
drivers/misc/gpio-logic-analyzer.c | 355 ++++++++++++++++++
tools/debugging/gpio-logic-analyzer | 156 ++++++++
7 files changed, 628 insertions(+)
create mode 100644 Documentation/dev-tools/gpio-logic-analyzer.rst
create mode 100644 Documentation/devicetree/bindings/misc/gpio-logic-analyzer.yaml
create mode 100644 drivers/misc/gpio-logic-analyzer.c
create mode 100755 tools/debugging/gpio-logic-analyzer
--
2.30.0
next reply other threads:[~2021-03-30 8:58 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-30 8:56 Wolfram Sang [this message]
2021-03-30 8:56 ` [PATCH RFC/RFT 1/1] misc: add simple logic analyzer using polling Wolfram Sang
2021-03-30 10:49 ` Andy Shevchenko
2021-03-30 15:41 ` Wolfram Sang
2021-03-30 18:18 ` Randy Dunlap
2021-03-30 18:44 ` Wolfram Sang
2021-04-01 13:07 ` Linus Walleij
2021-04-01 14:25 ` Bartosz Golaszewski
2021-04-01 21:45 ` Wolfram Sang
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