From patchwork Mon Nov 21 14:39:56 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 13051190 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 508D4C433FE for ; Mon, 21 Nov 2022 14:49:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231878AbiKUOto (ORCPT ); Mon, 21 Nov 2022 09:49:44 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40774 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232533AbiKUOsO (ORCPT ); Mon, 21 Nov 2022 09:48:14 -0500 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 95AE8D33B8; Mon, 21 Nov 2022 06:42:09 -0800 (PST) Message-ID: <20221121140049.679827689@linutronix.de> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1669041596; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: references:references; bh=fNlJq7eUueydjyHA34mJBe9PSXy3iovJN7ArQPlOsWU=; b=R66Bn3oMfKbAtRRfMMszVlBS+aGiqDqLdJzWQVM7YC9/DMBe6MNJKW7bMy8QT/0z0RCDdE oaju4mmWCHRGR/tiMvp5qEQCni0VBKIuXN4EjHphh9slImL/oWrNgH3kKOHlRZWe0SYNi0 13mPES8l9aOkXsyk88Uj8g4rm1aXrB8TikYqTgEZzpnjwDjjrYH6gydH4jj6Lcys5jDsUh ulXkLA5eyvAzwWDLYNIw59E12iqnwh9et+i8C0H83k4Qh+iN1x1Xa/r1ii8or9BoZA3XfI vRc7b7zghEEz9r37fw4mit2QEG0Z01Fj7DM13ie0CIZNJESChT0dT15oZPE/9Q== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1669041596; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: references:references; bh=fNlJq7eUueydjyHA34mJBe9PSXy3iovJN7ArQPlOsWU=; b=8EZXOY4u5eB2hDqCFbU5zgotL72sPCtlKFZCE3GO3oA1y1NhwRQwlQSE32pIYk8sv8Wwx6 Z6WW4edgQ7gcI7CQ== From: Thomas Gleixner To: LKML Cc: Will Deacon , linux-pci@vger.kernel.org, Bjorn Helgaas , Lorenzo Pieralisi , Marc Zyngier , Greg Kroah-Hartman , Jason Gunthorpe , Andrew Lunn , Gregory Clement , Sebastian Hesselbarth , Ammar Faizi , Robin Murphy , Lorenzo Pieralisi , Nishanth Menon , Tero Kristo , Santosh Shilimkar , linux-arm-kernel@lists.infradead.org, Vinod Koul , Sinan Kaya , Andy Gross , Bjorn Andersson , Mark Rutland , Shameerali Kolothum Thodi , Zenghui Yu , Shawn Guo , Sascha Hauer , Fabio Estevam Subject: [patch V2 22/40] genirq/msi: Provide allocation/free functions for "wired" MSI interrupts References: <20221121135653.208611233@linutronix.de> MIME-Version: 1.0 Date: Mon, 21 Nov 2022 15:39:56 +0100 (CET) Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org To support wire to MSI bridges proper in the MSI core infrastructure it is required to have separate allocation/free interfaces which can be invoked from the regular irqdomain allocaton/free functions. The mechanism for allocation is: - Allocate the next free MSI descriptor index in the domain - Store the hardware interrupt number and the trigger type which was extracted by the irqdomain core from the firmware spec in the MSI descriptor device cookie so it can be retrieved by the underlying interrupt domain and interrupt chip - Use the regular MSI allocation mechanism for the newly allocated index which returns a fully initialized Linux interrupt on succes This works because: - the domains have a fixed size - each hardware interrupt is only allocated once - the underlying domain does not care about the MSI index it only cares about the hardware interrupt number and the trigger type The free function looks up the MSI index in the MSI descriptor of the provided Linux interrupt number and uses the regular index based free functions of the MSI core. Signed-off-by: Thomas Gleixner --- include/linux/irqdomain.h | 17 +++++++++++ kernel/irq/msi.c | 68 ++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 85 insertions(+) --- a/include/linux/irqdomain.h +++ b/include/linux/irqdomain.h @@ -634,6 +634,23 @@ static inline bool irq_domain_is_msi_dev #endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */ +#ifdef CONFIG_GENERIC_MSI_IRQ +int msi_device_domain_alloc_wired(struct irq_domain *domain, unsigned int hwirq, + unsigned int type); +void msi_device_domain_free_wired(struct irq_domain *domain, unsigned int virq); +#else +static inline int msi_device_domain_alloc_wired(struct irq_domain *domain, unsigned int hwirq, + unsigned int type) +{ + WARN_ON_ONCE(1); + return -EINVAL; +} +static inline void msi_device_domain_free_wired(struct irq_domain *domain, unsigned int virq) +{ + WARN_ON_ONCE(1); +} +#endif + #else /* CONFIG_IRQ_DOMAIN */ static inline void irq_dispose_mapping(unsigned int virq) { } static inline struct irq_domain *irq_find_matching_fwnode( --- a/kernel/irq/msi.c +++ b/kernel/irq/msi.c @@ -1561,6 +1561,50 @@ struct msi_map msi_domain_alloc_irq_at(s return map; } +/** + * msi_device_domain_alloc_wired - Allocate a "wired" interrupt on @domain + * @domain: The domain to allocate on + * @hwirq: The hardware interrupt number to allocate for + * @type: The interrupt type + * + * This weirdness supports wire to MSI controllers like MBIGEN. + * + * @hwirq is the hardware interrupt number which is handed in from + * irq_create_fwspec_mapping(). As the wire to MSI domain is sparse, but + * sized in firmware, the hardware interrupt number cannot be used as MSI + * index. For the underlying irq chip the MSI index is irrelevant and + * all it needs is the hardware interrupt number. + * + * To handle this the MSI index is allocated with MSI_ANY_INDEX and the + * hardware interrupt number is stored along with the type information in + * msi_desc::cookie so the underlying interrupt chip and domain code can + * retrieve it. + * + * Return: The Linux interrupt number (> 0) or an error code + */ +int msi_device_domain_alloc_wired(struct irq_domain *domain, unsigned int hwirq, + unsigned int type) +{ + unsigned int domid = MSI_DEFAULT_DOMAIN; + union msi_instance_cookie icookie = { }; + struct device *dev = domain->dev; + struct msi_map map = { }; + + if (WARN_ON_ONCE(!dev || domain->bus_token != DOMAIN_BUS_WIRED_TO_MSI)) + return -EINVAL; + + icookie.value = ((u64)type << 32) | hwirq; + + msi_lock_descs(dev); + if (WARN_ON_ONCE(msi_get_device_domain(dev, domid) != domain)) + map.index = -EINVAL; + else + map = __msi_domain_alloc_irq_at(dev, domid, MSI_ANY_INDEX, NULL, &icookie); + msi_unlock_descs(dev); + + return map.index >= 0 ? map.virq : map.index; +} + static void __msi_domain_free_irqs(struct device *dev, struct irq_domain *domain, struct msi_ctrl *ctrl) { @@ -1688,6 +1732,30 @@ void msi_domain_free_irqs_all(struct dev msi_unlock_descs(dev); } +/** + * msi_device_domain_free_wired - Free a wired interrupt in @domain + * @domain: The domain to free the interrupt on + * @virq: The Linux interrupt number to free + * + * This is the counterpart of msi_device_domain_alloc_wired() for the + * weird wired to MSI converting domains. + */ +void msi_device_domain_free_wired(struct irq_domain *domain, unsigned int virq) +{ + struct msi_desc *desc = irq_get_msi_desc(virq); + struct device *dev = domain->dev; + + if (WARN_ON_ONCE(!dev || !desc || domain->bus_token != DOMAIN_BUS_WIRED_TO_MSI)) + return; + + msi_lock_descs(dev); + if (!WARN_ON_ONCE(msi_get_device_domain(dev, MSI_DEFAULT_DOMAIN) != domain)) { + msi_domain_free_irqs_range_locked(dev, MSI_DEFAULT_DOMAIN, desc->msi_index, + desc->msi_index); + } + msi_unlock_descs(dev); +} + /** * msi_get_domain_info - Get the MSI interrupt domain info for @domain * @domain: The interrupt domain to retrieve data from