From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> To: Elliot Berman <quic_eberman@quicinc.com> Cc: Jiri Slaby <jirislaby@kernel.org>, Bjorn Andersson <quic_bjorande@quicinc.com>, Murali Nalajala <quic_mnalajal@quicinc.com>, Trilok Soni <quic_tsoni@quicinc.com>, Srivatsa Vaddagiri <quic_svaddagi@quicinc.com>, Carl van Schaik <quic_cvanscha@quicinc.com>, Prakruthi Deepak Heragu <quic_pheragu@quicinc.com>, Andy Gross <agross@kernel.org>, Dmitry Baryshkov <dmitry.baryshkov@linaro.org>, Jassi Brar <jassisinghbrar@gmail.com>, linux-arm-kernel@lists.infradead.org, Mark Rutland <mark.rutland@arm.com>, Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>, Sudeep Holla <sudeep.holla@arm.com>, Marc Zyngier <maz@kernel.org>, Rob Herring <robh+dt@kernel.org>, Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>, Jonathan Corbet <corbet@lwn.net>, Will Deacon <will@kernel.org>, Catalin Marinas <catalin.marinas@arm.com>, Arnd Bergmann <arnd@arndb.de>, devicetree@vger.kernel.org, linux-doc@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 14/14] tty: gunyah: Add tty console driver for RM Console Services Date: Mon, 10 Oct 2022 22:23:29 +0200 [thread overview] Message-ID: <Y0R/QbysXa6ebNd8@kroah.com> (raw) In-Reply-To: <615493a8-449d-b105-709e-0642dfb5359b@quicinc.com> On Sun, Oct 09, 2022 at 01:59:21PM -0700, Elliot Berman wrote: > > > On 10/7/2022 12:40 AM, Greg Kroah-Hartman wrote: > > On Thu, Oct 06, 2022 at 10:59:51PM -0700, Elliot Berman wrote: > > > > > > "GH" is the shorthand we've been using for "Gunyah". I didn't find > > > documentation for dynamically assigned char devices, but if it exists, I can > > > add entry for ttyGH. > > > > Why use a new name at all? Why not stick with the existing tty names > > and device numbers? > > > > I can use hvc framework, although driver-level buffering is needed on > both the get_chars/put_chars paths because: I'm not asking about the framework (although that is a good question, you need to document why this has to be new.) I'm asking why pick a new name? You will not have a name conflict in your system with this device with any other tty name right? > - get_chars wants to poll for characters, but Gunyah will push > characters to Linux > - put_chars can be called in atomic context in the printk console path. > Gunyah RM calls can sleep, so we add to buffer and queue work to > write the characters. > > I also chose to use new tty driver because the Gunyah hypervisor call to > open the console (gh_rm_console_open) can only be done after starting the > VM. Gunyah will only forward characters sent from the other VM to Linux > after the gh_rm_console_open call is made. When launching a VM, users would > want to open console before VM starts so they can get startup messages from > the VM. I planned to use the carrier_raised() to hold > tty_port_block_until_ready until the VM is started and the > gh_rm_console_open() happens. I'm sorry, but I don't understand this. Why is this all a new api at all? What about the virtio api? Why not just use that instead? thanks, greg k-h
WARNING: multiple messages have this Message-ID (diff)
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> To: Elliot Berman <quic_eberman@quicinc.com> Cc: Jiri Slaby <jirislaby@kernel.org>, Bjorn Andersson <quic_bjorande@quicinc.com>, Murali Nalajala <quic_mnalajal@quicinc.com>, Trilok Soni <quic_tsoni@quicinc.com>, Srivatsa Vaddagiri <quic_svaddagi@quicinc.com>, Carl van Schaik <quic_cvanscha@quicinc.com>, Prakruthi Deepak Heragu <quic_pheragu@quicinc.com>, Andy Gross <agross@kernel.org>, Dmitry Baryshkov <dmitry.baryshkov@linaro.org>, Jassi Brar <jassisinghbrar@gmail.com>, linux-arm-kernel@lists.infradead.org, Mark Rutland <mark.rutland@arm.com>, Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>, Sudeep Holla <sudeep.holla@arm.com>, Marc Zyngier <maz@kernel.org>, Rob Herring <robh+dt@kernel.org>, Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>, Jonathan Corbet <corbet@lwn.net>, Will Deacon <will@kernel.org>, Catalin Marinas <catalin.marinas@arm.com>, Arnd Bergmann <arnd@arndb.de>, devicetree@vger.kernel.org, linux-doc@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 14/14] tty: gunyah: Add tty console driver for RM Console Services Date: Mon, 10 Oct 2022 22:23:29 +0200 [thread overview] Message-ID: <Y0R/QbysXa6ebNd8@kroah.com> (raw) In-Reply-To: <615493a8-449d-b105-709e-0642dfb5359b@quicinc.com> On Sun, Oct 09, 2022 at 01:59:21PM -0700, Elliot Berman wrote: > > > On 10/7/2022 12:40 AM, Greg Kroah-Hartman wrote: > > On Thu, Oct 06, 2022 at 10:59:51PM -0700, Elliot Berman wrote: > > > > > > "GH" is the shorthand we've been using for "Gunyah". I didn't find > > > documentation for dynamically assigned char devices, but if it exists, I can > > > add entry for ttyGH. > > > > Why use a new name at all? Why not stick with the existing tty names > > and device numbers? > > > > I can use hvc framework, although driver-level buffering is needed on > both the get_chars/put_chars paths because: I'm not asking about the framework (although that is a good question, you need to document why this has to be new.) I'm asking why pick a new name? You will not have a name conflict in your system with this device with any other tty name right? > - get_chars wants to poll for characters, but Gunyah will push > characters to Linux > - put_chars can be called in atomic context in the printk console path. > Gunyah RM calls can sleep, so we add to buffer and queue work to > write the characters. > > I also chose to use new tty driver because the Gunyah hypervisor call to > open the console (gh_rm_console_open) can only be done after starting the > VM. Gunyah will only forward characters sent from the other VM to Linux > after the gh_rm_console_open call is made. When launching a VM, users would > want to open console before VM starts so they can get startup messages from > the VM. I planned to use the carrier_raised() to hold > tty_port_block_until_ready until the VM is started and the > gh_rm_console_open() happens. I'm sorry, but I don't understand this. Why is this all a new api at all? What about the virtio api? Why not just use that instead? thanks, greg k-h _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2022-10-10 20:25 UTC|newest] Thread overview: 102+ messages / expand[flat|nested] mbox.gz Atom feed top 2022-09-28 19:56 [PATCH v4 00/14] Drivers for gunyah hypervisor Elliot Berman 2022-09-28 19:56 ` Elliot Berman 2022-09-28 19:56 ` [PATCH v4 01/14] docs: gunyah: Introduce Gunyah Hypervisor Elliot Berman 2022-09-28 19:56 ` Elliot Berman 2022-09-29 3:43 ` Bagas Sanjaya 2022-09-29 3:43 ` Bagas Sanjaya 2022-09-29 4:02 ` Elliot Berman 2022-09-29 4:02 ` Elliot Berman 2022-09-28 19:56 ` [PATCH v4 02/14] dt-bindings: Add binding for gunyah hypervisor Elliot Berman 2022-09-28 19:56 ` Elliot Berman 2022-09-28 19:56 ` [PATCH v4 03/14] gunyah: Common types and error codes for Gunyah hypercalls Elliot Berman 2022-09-28 19:56 ` Elliot Berman 2022-09-28 19:56 ` [PATCH v4 04/14] arm64: smccc: Include alternative-macros.h Elliot Berman 2022-09-28 19:56 ` Elliot Berman 2022-09-28 19:56 ` [PATCH v4 05/14] virt: gunyah: Add hypercalls to identify Gunyah Elliot Berman 2022-09-28 19:56 ` Elliot Berman 2022-09-28 19:56 ` [PATCH v4 06/14] virt: gunyah: Add sysfs nodes Elliot Berman 2022-09-28 19:56 ` Elliot Berman 2022-09-30 12:09 ` Greg Kroah-Hartman 2022-09-30 12:09 ` Greg Kroah-Hartman 2022-10-04 23:50 ` Elliot Berman 2022-10-04 23:50 ` Elliot Berman 2022-10-05 6:23 ` Greg Kroah-Hartman 2022-10-05 6:23 ` Greg Kroah-Hartman 2022-09-28 19:56 ` [PATCH v4 07/14] mailbox: Allow direct registration to a channel Elliot Berman 2022-09-28 19:56 ` Elliot Berman 2022-09-28 19:56 ` [PATCH v4 08/14] virt: gunyah: msgq: Add hypercalls to send and receive messages Elliot Berman 2022-09-28 19:56 ` Elliot Berman 2022-09-28 19:56 ` [PATCH v4 09/14] mailbox: Add Gunyah message queue mailbox Elliot Berman 2022-09-28 19:56 ` Elliot Berman 2022-09-29 16:59 ` Bjorn Andersson 2022-09-29 16:59 ` Bjorn Andersson 2022-09-29 17:37 ` Jassi Brar 2022-09-29 17:37 ` Jassi Brar 2022-09-28 19:56 ` [PATCH v4 10/14] gunyah: sysfs: Add node to describe supported features Elliot Berman 2022-09-28 19:56 ` Elliot Berman 2022-09-29 7:36 ` Joe Perches 2022-09-29 7:36 ` Joe Perches 2022-09-29 20:47 ` Elliot Berman 2022-09-29 20:47 ` Elliot Berman 2022-10-02 23:30 ` Jeff Johnson 2022-10-02 23:30 ` Jeff Johnson 2022-10-02 23:58 ` Joe Perches 2022-10-02 23:58 ` Joe Perches 2022-09-30 12:06 ` Greg Kroah-Hartman 2022-09-30 12:06 ` Greg Kroah-Hartman 2022-10-04 23:53 ` Elliot Berman 2022-10-04 23:53 ` Elliot Berman 2022-09-28 19:56 ` [PATCH v4 11/14] gunyah: rsc_mgr: Add resource manager RPC core Elliot Berman 2022-09-28 19:56 ` Elliot Berman 2022-09-28 19:56 ` [PATCH v4 12/14] gunyah: rsc_mgr: Add RPC for console services Elliot Berman 2022-09-28 19:56 ` Elliot Berman 2022-09-30 12:22 ` Greg Kroah-Hartman 2022-09-30 12:22 ` Greg Kroah-Hartman 2022-10-03 1:46 ` new checkpatch flexible array test ? (was Re: [PATCH v4 12/14] gunyah: rsc_mgr: Add RPC for console services) Joe Perches 2022-10-03 1:46 ` Joe Perches 2022-10-03 5:29 ` Greg Kroah-Hartman 2022-10-03 5:29 ` Greg Kroah-Hartman 2022-10-03 5:38 ` Joe Perches 2022-10-03 5:38 ` Joe Perches 2022-10-31 18:23 ` Gustavo A. R. Silva 2022-10-31 18:23 ` Gustavo A. R. Silva 2022-09-28 19:56 ` [PATCH v4 13/14] gunyah: rsc_mgr: Add auxiliary devices for console Elliot Berman 2022-09-28 19:56 ` Elliot Berman 2022-09-30 12:19 ` Greg Kroah-Hartman 2022-09-30 12:19 ` Greg Kroah-Hartman 2022-10-04 23:49 ` Elliot Berman 2022-10-04 23:49 ` Elliot Berman 2022-10-05 6:21 ` Greg Kroah-Hartman 2022-10-05 6:21 ` Greg Kroah-Hartman 2022-10-05 21:47 ` Elliot Berman 2022-10-05 21:47 ` Elliot Berman 2022-10-06 6:28 ` Greg Kroah-Hartman 2022-10-06 6:28 ` Greg Kroah-Hartman 2022-09-28 19:56 ` [PATCH v4 14/14] tty: gunyah: Add tty console driver for RM Console Services Elliot Berman 2022-09-28 19:56 ` Elliot Berman 2022-09-30 12:17 ` Greg Kroah-Hartman 2022-09-30 12:17 ` Greg Kroah-Hartman 2022-10-07 5:59 ` Elliot Berman 2022-10-07 5:59 ` Elliot Berman 2022-10-07 7:40 ` Greg Kroah-Hartman 2022-10-07 7:40 ` Greg Kroah-Hartman 2022-10-09 20:59 ` Elliot Berman 2022-10-09 20:59 ` Elliot Berman 2022-10-10 20:23 ` Greg Kroah-Hartman [this message] 2022-10-10 20:23 ` Greg Kroah-Hartman 2022-10-10 20:58 ` Elliot Berman 2022-10-10 20:58 ` Elliot Berman 2022-10-11 6:22 ` Greg Kroah-Hartman 2022-10-11 6:22 ` Greg Kroah-Hartman 2022-10-11 22:04 ` Elliot Berman 2022-10-11 22:04 ` Elliot Berman 2022-10-12 6:53 ` Greg Kroah-Hartman 2022-10-12 6:53 ` Greg Kroah-Hartman 2022-10-08 7:41 ` Zhou Furong 2022-10-08 7:41 ` Zhou Furong 2022-10-08 9:52 ` Greg Kroah-Hartman 2022-10-08 9:52 ` Greg Kroah-Hartman 2022-10-03 7:01 ` Jiri Slaby 2022-10-03 7:01 ` Jiri Slaby 2022-10-10 18:06 ` Elliot Berman 2022-10-10 18:06 ` Elliot Berman
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=Y0R/QbysXa6ebNd8@kroah.com \ --to=gregkh@linuxfoundation.org \ --cc=agross@kernel.org \ --cc=arnd@arndb.de \ --cc=catalin.marinas@arm.com \ --cc=corbet@lwn.net \ --cc=devicetree@vger.kernel.org \ --cc=dmitry.baryshkov@linaro.org \ --cc=jassisinghbrar@gmail.com \ --cc=jirislaby@kernel.org \ --cc=krzysztof.kozlowski+dt@linaro.org \ --cc=linux-arm-kernel@lists.infradead.org \ --cc=linux-arm-msm@vger.kernel.org \ --cc=linux-doc@vger.kernel.org \ --cc=linux-kernel@vger.kernel.org \ --cc=lorenzo.pieralisi@arm.com \ --cc=mark.rutland@arm.com \ --cc=maz@kernel.org \ --cc=quic_bjorande@quicinc.com \ --cc=quic_cvanscha@quicinc.com \ --cc=quic_eberman@quicinc.com \ --cc=quic_mnalajal@quicinc.com \ --cc=quic_pheragu@quicinc.com \ --cc=quic_svaddagi@quicinc.com \ --cc=quic_tsoni@quicinc.com \ --cc=robh+dt@kernel.org \ --cc=sudeep.holla@arm.com \ --cc=will@kernel.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: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.