From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-11.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D1B7FC43331 for ; Sun, 29 Mar 2020 20:26:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A64F92074A for ; Sun, 29 Mar 2020 20:26:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728774AbgC2U0O (ORCPT ); Sun, 29 Mar 2020 16:26:14 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:56914 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727903AbgC2U0M (ORCPT ); Sun, 29 Mar 2020 16:26:12 -0400 Received: from [5.158.153.53] (helo=tip-bot2.lab.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1jIeVU-0001KF-DR; Sun, 29 Mar 2020 22:26:08 +0200 Received: from [127.0.1.1] (localhost [IPv6:::1]) by tip-bot2.lab.linutronix.de (Postfix) with ESMTP id EE4CA1C0334; Sun, 29 Mar 2020 22:26:07 +0200 (CEST) Date: Sun, 29 Mar 2020 20:26:07 -0000 From: "tip-bot2 for Marc Zyngier" Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: irq/core] irqchip/gic-v4.1: Plumb get/set_irqchip_state SGI callbacks Cc: Marc Zyngier , Zenghui Yu , x86 , LKML In-Reply-To: <20200304203330.4967-12-maz@kernel.org> References: <20200304203330.4967-12-maz@kernel.org> MIME-Version: 1.0 Message-ID: <158551356759.28353.1282710549164334441.tip-bot2@tip-bot2> X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the irq/core branch of tip: Commit-ID: 7017ff0ee1de9d45fafee88a4e7890cce92f482e Gitweb: https://git.kernel.org/tip/7017ff0ee1de9d45fafee88a4e7890cce92f482e Author: Marc Zyngier AuthorDate: Wed, 04 Mar 2020 20:33:18 Committer: Marc Zyngier CommitterDate: Tue, 24 Mar 2020 12:05:09 irqchip/gic-v4.1: Plumb get/set_irqchip_state SGI callbacks To implement the get/set_irqchip_state callbacks (limited to the PENDING state), we have to use a particular set of hacks: - Reading the pending state is done by using a pair of new redistributor registers (GICR_VSGIR, GICR_VSGIPENDR), which allow the 16 interrupts state to be retrieved. - Setting the pending state is done by generating it as we'd otherwise do for a guest (writing to GITS_SGIR). - Clearing the pending state is done by emitting a VSGI command with the "clear" bit set. This requires some interesting locking though: - When talking to the redistributor, we must make sure that the VPE affinity doesn't change, hence taking the VPE lock. - At the same time, we must ensure that nobody accesses the same redistributor's GICR_VSGIR registers for a different VPE, which would corrupt the reading of the pending bits. We thus take the per-RD spinlock. Much fun. Signed-off-by: Marc Zyngier Reviewed-by: Zenghui Yu Link: https://lore.kernel.org/r/20200304203330.4967-12-maz@kernel.org --- drivers/irqchip/irq-gic-v3-its.c | 77 +++++++++++++++++++++++++++++- include/linux/irqchip/arm-gic-v3.h | 14 +++++- 2 files changed, 91 insertions(+) diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c index bc6666a..c614f0c 100644 --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -3972,11 +3972,88 @@ static int its_sgi_set_affinity(struct irq_data *d, return IRQ_SET_MASK_OK; } +static int its_sgi_set_irqchip_state(struct irq_data *d, + enum irqchip_irq_state which, + bool state) +{ + if (which != IRQCHIP_STATE_PENDING) + return -EINVAL; + + if (state) { + struct its_vpe *vpe = irq_data_get_irq_chip_data(d); + struct its_node *its = find_4_1_its(); + u64 val; + + val = FIELD_PREP(GITS_SGIR_VPEID, vpe->vpe_id); + val |= FIELD_PREP(GITS_SGIR_VINTID, d->hwirq); + writeq_relaxed(val, its->sgir_base + GITS_SGIR - SZ_128K); + } else { + its_configure_sgi(d, true); + } + + return 0; +} + +static int its_sgi_get_irqchip_state(struct irq_data *d, + enum irqchip_irq_state which, bool *val) +{ + struct its_vpe *vpe = irq_data_get_irq_chip_data(d); + void __iomem *base; + unsigned long flags; + u32 count = 1000000; /* 1s! */ + u32 status; + int cpu; + + if (which != IRQCHIP_STATE_PENDING) + return -EINVAL; + + /* + * Locking galore! We can race against two different events: + * + * - Concurent vPE affinity change: we must make sure it cannot + * happen, or we'll talk to the wrong redistributor. This is + * identical to what happens with vLPIs. + * + * - Concurrent VSGIPENDR access: As it involves accessing two + * MMIO registers, this must be made atomic one way or another. + */ + cpu = vpe_to_cpuid_lock(vpe, &flags); + raw_spin_lock(&gic_data_rdist_cpu(cpu)->rd_lock); + base = gic_data_rdist_cpu(cpu)->rd_base + SZ_128K; + writel_relaxed(vpe->vpe_id, base + GICR_VSGIR); + do { + status = readl_relaxed(base + GICR_VSGIPENDR); + if (!(status & GICR_VSGIPENDR_BUSY)) + goto out; + + count--; + if (!count) { + pr_err_ratelimited("Unable to get SGI status\n"); + goto out; + } + cpu_relax(); + udelay(1); + } while (count); + +out: + raw_spin_unlock(&gic_data_rdist_cpu(cpu)->rd_lock); + vpe_to_cpuid_unlock(vpe, flags); + + if (!count) + return -ENXIO; + + *val = !!(status & (1 << d->hwirq)); + + return 0; +} + static struct irq_chip its_sgi_irq_chip = { .name = "GICv4.1-sgi", .irq_mask = its_sgi_mask_irq, .irq_unmask = its_sgi_unmask_irq, .irq_set_affinity = its_sgi_set_affinity, + .irq_set_irqchip_state = its_sgi_set_irqchip_state, + .irq_get_irqchip_state = its_sgi_get_irqchip_state, }; static int its_sgi_irq_domain_alloc(struct irq_domain *domain, diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h index fd3be49..590cdbe 100644 --- a/include/linux/irqchip/arm-gic-v3.h +++ b/include/linux/irqchip/arm-gic-v3.h @@ -345,6 +345,15 @@ #define GICR_VPENDBASER_4_1_VGRP1EN (1ULL << 58) #define GICR_VPENDBASER_4_1_VPEID GENMASK_ULL(15, 0) +#define GICR_VSGIR 0x0080 + +#define GICR_VSGIR_VPEID GENMASK(15, 0) + +#define GICR_VSGIPENDR 0x0088 + +#define GICR_VSGIPENDR_BUSY (1U << 31) +#define GICR_VSGIPENDR_PENDING GENMASK(15, 0) + /* * ITS registers, offsets from ITS_base */ @@ -368,6 +377,11 @@ #define GITS_TRANSLATER 0x10040 +#define GITS_SGIR 0x20020 + +#define GITS_SGIR_VPEID GENMASK_ULL(47, 32) +#define GITS_SGIR_VINTID GENMASK_ULL(3, 0) + #define GITS_CTLR_ENABLE (1U << 0) #define GITS_CTLR_ImDe (1U << 1) #define GITS_CTLR_ITS_NUMBER_SHIFT 4