From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6AA4C26E705; Thu, 7 Aug 2025 16:25:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754583923; cv=none; b=YkWTsMuIwwhjaZJGhzuatVLcMVw/JlTUTCg4zjCb7RB36kQ9tQjkEO085l9MGTXCbJ2oy2001XtapF1K5Gg7K1uqVpE+Qi3WzR27f7B6KC8e5y2Pib9ctuwzDrDnKn/9BAljEpWhtUPwi0A7aMbOE3vbAUJDYymYKiHp19O/gLU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754583923; c=relaxed/simple; bh=BudXXcTDGTwxVD8ktjRz+4NV9TJy0IkwNxbBa3LWQks=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; b=CT2wAi0jff3+7cFcFlMHvl2BK9EVrG9aQcLDUT4olyRJ1i/jOCleUkolUABFeroCF6pxAEwAJFGqRIoBVcUC9lxFkcjFY8oobYiny8qH57qek0fGh509jT24NXlwqdfBQM64dMylo0kX8f1aIEIJ1BjedkGo56ObkfYVbwsk9rQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=P5sSS+2O; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="P5sSS+2O" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D9EEBC4CEEB; Thu, 7 Aug 2025 16:25:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1754583923; bh=BudXXcTDGTwxVD8ktjRz+4NV9TJy0IkwNxbBa3LWQks=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=P5sSS+2OTaPHfKQ7mMNN/uSkilMMoN7DDZ7CND1CGKyvRJE85TL0J6gTIlABwqnSA NQXDcKFq5gydWUbE51EneYcRKby3Lu1TIymbHRfnZ/HY4R90XkkumVfQZmjF8JFOlh p2Qab2ZgAcxuHDjL72Zpd+sWhiUwVpXPsOiREIQ8FDJr254F5p2hC15CZ38aLUu6Br 9boLOT1C0N4HuvQwpmyLVj0YwF248CMixT7+SS6YtmqBuw02RE06jDW5VVe2hGqbsS SHroNrEgmVyO4DJBAuwbtd1QXtnPtQCt6nFke40HU1txhdHAketkb22ynmYr6gHKU2 NtateoowuMeEw== Date: Thu, 7 Aug 2025 11:25:21 -0500 From: Bjorn Helgaas To: Inochi Amaoto Cc: Thomas Gleixner , Bjorn Helgaas , Marc Zyngier , Lorenzo Pieralisi , Saurabh Sengar , Shradha Gupta , Jonathan Cameron , Nicolin Chen , Jason Gunthorpe , Chen Wang , linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, Yixun Lan , Longbin Li Subject: Re: [PATCH 2/4] PCI/MSI: Add startup/shutdown support for per device MSI[X] domains Message-ID: <20250807162521.GA50955@bhelgaas> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250807112326.748740-3-inochiama@gmail.com> In subject, s/MSI[X]// and s/support for/for/ The "MSI[X]" notation really isn't used anywhere else, and we already include "PCI/MSI" in the prefix, so I don't think we need it again. On Thu, Aug 07, 2025 at 07:23:23PM +0800, Inochi Amaoto wrote: > As The RISC-V PLIC can not apply affinity setting without calling > irq_enable(), it will make the interrupt unavaible when using as > an underlying irq chip for MSI controller. s/As The/As the/ s/unavaible/unavailable/ s/irq chip/IRQ chip/ > Introduce the irq_startup/irq_shutdown for PCI domain template with > new MSI domain flag. This allow the PLIC can be properly configurated > when calling irq_startup(). Maybe something like: Implement .irq_startup() and .irq_shutdown() for the PCI MSI and MSI-X templates. For chips that specify MSI_FLAG_PCI_MSI_STARTUP_PARENT, these startup and shutdown the parent as well, which allows ... s/This allow/This allows/ s/can be properly configurated/to be configured/ Evidently PLIC depends on this "parent" connection, but that isn't explained at all in the commit log. > Suggested-by: Thomas Gleixner > Signed-off-by: Inochi Amaoto > --- > drivers/pci/msi/irqdomain.c | 52 +++++++++++++++++++++++++++++++++++++ > include/linux/msi.h | 2 ++ > 2 files changed, 54 insertions(+) > > diff --git a/drivers/pci/msi/irqdomain.c b/drivers/pci/msi/irqdomain.c > index 0938ef7ebabf..f0d18cadbe20 100644 > --- a/drivers/pci/msi/irqdomain.c > +++ b/drivers/pci/msi/irqdomain.c > @@ -148,6 +148,23 @@ static void pci_device_domain_set_desc(msi_alloc_info_t *arg, struct msi_desc *d > arg->hwirq = desc->msi_index; > } > > +static __always_inline void cond_shutdown_parent(struct irq_data *data) Is there a functional reason why we need __always_inline? If not, it seems like this annotation is just clutter, and the compiler will probably inline it all by itself. > +{ > + struct msi_domain_info *info = data->domain->host_data; > + > + if (unlikely(info->flags & MSI_FLAG_PCI_MSI_STARTUP_PARENT)) > + irq_chip_shutdown_parent(data); > +} > + > +static __always_inline unsigned int cond_startup_parent(struct irq_data *data) > +{ > + struct msi_domain_info *info = data->domain->host_data; > + > + if (unlikely(info->flags & MSI_FLAG_PCI_MSI_STARTUP_PARENT)) > + return irq_chip_startup_parent(data); > + return 0; > +} > + > static __always_inline void cond_mask_parent(struct irq_data *data) > { > struct msi_domain_info *info = data->domain->host_data; > @@ -164,6 +181,23 @@ static __always_inline void cond_unmask_parent(struct irq_data *data) > irq_chip_unmask_parent(data); > } > > +static void pci_irq_shutdown_msi(struct irq_data *data) > +{ > + struct msi_desc *desc = irq_data_get_msi_desc(data); > + > + pci_msi_mask(desc, BIT(data->irq - desc->irq)); > + cond_shutdown_parent(data); > +} > + > +static unsigned int pci_irq_startup_msi(struct irq_data *data) > +{ > + struct msi_desc *desc = irq_data_get_msi_desc(data); > + unsigned int ret = cond_startup_parent(data); > + > + pci_msi_unmask(desc, BIT(data->irq - desc->irq)); > + return ret; > +} > + > static void pci_irq_mask_msi(struct irq_data *data) > { > struct msi_desc *desc = irq_data_get_msi_desc(data); > @@ -194,6 +228,8 @@ static void pci_irq_unmask_msi(struct irq_data *data) > static const struct msi_domain_template pci_msi_template = { > .chip = { > .name = "PCI-MSI", > + .irq_startup = pci_irq_startup_msi, > + .irq_shutdown = pci_irq_shutdown_msi, > .irq_mask = pci_irq_mask_msi, > .irq_unmask = pci_irq_unmask_msi, > .irq_write_msi_msg = pci_msi_domain_write_msg, > @@ -210,6 +246,20 @@ static const struct msi_domain_template pci_msi_template = { > }, > }; > > +static void pci_irq_shutdown_msix(struct irq_data *data) > +{ > + pci_msix_mask(irq_data_get_msi_desc(data)); > + cond_shutdown_parent(data); > +} > + > +static unsigned int pci_irq_startup_msix(struct irq_data *data) > +{ > + unsigned int ret = cond_startup_parent(data); > + > + pci_msix_unmask(irq_data_get_msi_desc(data)); > + return ret; > +} > + > static void pci_irq_mask_msix(struct irq_data *data) > { > pci_msix_mask(irq_data_get_msi_desc(data)); > @@ -234,6 +284,8 @@ EXPORT_SYMBOL_GPL(pci_msix_prepare_desc); > static const struct msi_domain_template pci_msix_template = { > .chip = { > .name = "PCI-MSIX", > + .irq_startup = pci_irq_startup_msix, > + .irq_shutdown = pci_irq_shutdown_msix, > .irq_mask = pci_irq_mask_msix, > .irq_unmask = pci_irq_unmask_msix, > .irq_write_msi_msg = pci_msi_domain_write_msg, > diff --git a/include/linux/msi.h b/include/linux/msi.h > index e5e86a8529fb..3111ba95fbde 100644 > --- a/include/linux/msi.h > +++ b/include/linux/msi.h > @@ -568,6 +568,8 @@ enum { > MSI_FLAG_PARENT_PM_DEV = (1 << 8), > /* Support for parent mask/unmask */ > MSI_FLAG_PCI_MSI_MASK_PARENT = (1 << 9), > + /* Support for parent startup/shutdown */ > + MSI_FLAG_PCI_MSI_STARTUP_PARENT = (1 << 10), > > /* Mask for the generic functionality */ > MSI_GENERIC_FLAGS_MASK = GENMASK(15, 0), > -- > 2.50.1 >