From patchwork Wed May 4 16:58:47 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Marek_Beh=C3=BAn?= X-Patchwork-Id: 569615 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 14B29C47085 for ; Wed, 4 May 2022 17:17:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349006AbiEDRUy (ORCPT ); Wed, 4 May 2022 13:20:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57536 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1358091AbiEDRPj (ORCPT ); Wed, 4 May 2022 13:15:39 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 924015641A for ; Wed, 4 May 2022 09:59:22 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 0E874B827B1 for ; Wed, 4 May 2022 16:59:20 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 90DAEC385AF; Wed, 4 May 2022 16:59:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1651683558; bh=Xl2G0VHedu4dg0hN9GTL4kbvsrxwQ2buA+lqgXoPxuA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Bo5geaexdl8NiQKfkClqbTaPL0vsOkVj/cqKkO2F8Bga4rgo1S6M7KxogLQX1khvD 0KpFjYg9hWz0veZFGzkqal7Psld0XO7m8kW0oqmseRIY9OghhjmCtg2L3gs59QqhpM V0h8KpHvDadaqPEhWnDc7KS9OxuuClUtA5vc5Kwk8tkNDxblg+fCrU7aBabA5+80C2 BzR/j4GCogK+zfGEOOkonjeCOlJGScsYnYIGjRuC1Q+N6rNWolWZcNWHVhCSOth0qX Z+2/fhmUVHbtUGNJCGFO6eGNtqBiF0n48PsDR92NVaMfQFSMeB1Ljy6ZWxm2+knyDv em7Iqa8QeJYGQ== From: =?utf-8?q?Marek_Beh=C3=BAn?= To: Greg Kroah-Hartman , Sasha Levin Cc: stable@vger.kernel.org, pali@kernel.org, =?utf-8?q?Marek_Beh=C3=BAn?= Subject: [PATCH 5.17 14/19] PCI: aardvark: Fix support for PME requester on emulated bridge Date: Wed, 4 May 2022 18:58:47 +0200 Message-Id: <20220504165852.30089-15-kabel@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220504165852.30089-1-kabel@kernel.org> References: <20220504165852.30089-1-kabel@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Pali Rohár commit 273ddd86d67694e3639e3bfe337a96d8861798b8 upstream. Enable aardvark PME interrupt unconditionally by unmasking it and read PME requester ID to emulated bridge config space immediately after receiving interrupt. PME requester ID is stored in the PCIE_MSG_LOG_REG register, which contains the last inbound message. So when new inbound message is received by HW (including non-PM), the content in PCIE_MSG_LOG_REG register is replaced by a new value. PCIe specification mandates that subsequent PMEs are kept pending until the PME Status Register bit is cleared by software by writing a 1b. Support for masking/unmasking PME interrupt on emulated bridge via PCI_EXP_RTCTL_PMEIE bit is now implemented only in emulated bridge config space, to ensure that we do not miss any aardvark PME interrupt. Reading of PCI_EXP_RTCAP and PCI_EXP_RTSTA registers is simplified as final value is now always stored into emulated bridge config space by the interrupt handler, so there is no need to implement support for these registers in read_pcie callback. Clearing of W1C bit PCI_EXP_RTSTA_PME is now also simplified as it is done by pci-bridge-emul.c code for emulated bridge config space. So there is no need to implement support for clearing this bit in write_pcie callback. Link: https://lore.kernel.org/r/20220110015018.26359-18-kabel@kernel.org Signed-off-by: Pali Rohár Signed-off-by: Marek Behún Signed-off-by: Lorenzo Pieralisi Signed-off-by: Marek Behún --- drivers/pci/controller/pci-aardvark.c | 91 +++++++++++++++------------ 1 file changed, 50 insertions(+), 41 deletions(-) diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c index 8020dfb8f00e..bd587f9395f8 100644 --- a/drivers/pci/controller/pci-aardvark.c +++ b/drivers/pci/controller/pci-aardvark.c @@ -590,6 +590,11 @@ static void advk_pcie_setup_hw(struct advk_pcie *pcie) reg &= ~PCIE_ISR0_MSI_INT_PENDING; advk_writel(pcie, reg, PCIE_ISR0_MASK_REG); + /* Unmask PME interrupt for processing of PME requester */ + reg = advk_readl(pcie, PCIE_ISR0_MASK_REG); + reg &= ~PCIE_MSG_PM_PME_MASK; + advk_writel(pcie, reg, PCIE_ISR0_MASK_REG); + /* Enable summary interrupt for GIC SPI source */ reg = PCIE_IRQ_ALL_MASK & (~PCIE_IRQ_ENABLE_INTS_MASK); advk_writel(pcie, reg, HOST_CTRL_INT_MASK_REG); @@ -856,22 +861,11 @@ advk_pci_bridge_emul_pcie_conf_read(struct pci_bridge_emul *bridge, *value = PCI_EXP_SLTSTA_PDS << 16; return PCI_BRIDGE_EMUL_HANDLED; - case PCI_EXP_RTCTL: { - u32 val = advk_readl(pcie, PCIE_ISR0_MASK_REG); - *value = (val & PCIE_MSG_PM_PME_MASK) ? 0 : PCI_EXP_RTCTL_PMEIE; - *value |= le16_to_cpu(bridge->pcie_conf.rootctl) & PCI_EXP_RTCTL_CRSSVE; - *value |= PCI_EXP_RTCAP_CRSVIS << 16; - return PCI_BRIDGE_EMUL_HANDLED; - } - - case PCI_EXP_RTSTA: { - u32 isr0 = advk_readl(pcie, PCIE_ISR0_REG); - u32 msglog = advk_readl(pcie, PCIE_MSG_LOG_REG); - *value = msglog >> 16; - if (isr0 & PCIE_MSG_PM_PME_MASK) - *value |= PCI_EXP_RTSTA_PME; - return PCI_BRIDGE_EMUL_HANDLED; - } + /* + * PCI_EXP_RTCTL and PCI_EXP_RTSTA are also supported, but do not need + * to be handled here, because their values are stored in emulated + * config space buffer, and we read them from there when needed. + */ case PCI_EXP_LNKCAP: { u32 val = advk_readl(pcie, PCIE_CORE_PCIEXP_CAP + reg); @@ -925,22 +919,19 @@ advk_pci_bridge_emul_pcie_conf_write(struct pci_bridge_emul *bridge, advk_pcie_wait_for_retrain(pcie); break; - case PCI_EXP_RTCTL: - /* Only mask/unmask PME interrupt */ - if (mask & PCI_EXP_RTCTL_PMEIE) { - u32 val = advk_readl(pcie, PCIE_ISR0_MASK_REG); - if (new & PCI_EXP_RTCTL_PMEIE) - val &= ~PCIE_MSG_PM_PME_MASK; - else - val |= PCIE_MSG_PM_PME_MASK; - advk_writel(pcie, val, PCIE_ISR0_MASK_REG); - } + case PCI_EXP_RTCTL: { + u16 rootctl = le16_to_cpu(bridge->pcie_conf.rootctl); + /* Only emulation of PMEIE and CRSSVE bits is provided */ + rootctl &= PCI_EXP_RTCTL_PMEIE | PCI_EXP_RTCTL_CRSSVE; + bridge->pcie_conf.rootctl = cpu_to_le16(rootctl); break; + } - case PCI_EXP_RTSTA: - if (new & PCI_EXP_RTSTA_PME) - advk_writel(pcie, PCIE_MSG_PM_PME_MASK, PCIE_ISR0_REG); - break; + /* + * PCI_EXP_RTSTA is also supported, but does not need to be handled + * here, because its value is stored in emulated config space buffer, + * and we write it there when needed. + */ case PCI_EXP_DEVCTL: case PCI_EXP_DEVCTL2: @@ -1443,6 +1434,32 @@ static void advk_pcie_remove_irq_domain(struct advk_pcie *pcie) irq_domain_remove(pcie->irq_domain); } +static void advk_pcie_handle_pme(struct advk_pcie *pcie) +{ + u32 requester = advk_readl(pcie, PCIE_MSG_LOG_REG) >> 16; + + advk_writel(pcie, PCIE_MSG_PM_PME_MASK, PCIE_ISR0_REG); + + /* + * PCIE_MSG_LOG_REG contains the last inbound message, so store + * the requester ID only when PME was not asserted yet. + * Also do not trigger PME interrupt when PME is still asserted. + */ + if (!(le32_to_cpu(pcie->bridge.pcie_conf.rootsta) & PCI_EXP_RTSTA_PME)) { + pcie->bridge.pcie_conf.rootsta = cpu_to_le32(requester | PCI_EXP_RTSTA_PME); + + /* + * Trigger PME interrupt only if PMEIE bit in Root Control is set. + * Aardvark HW returns zero for PCI_EXP_FLAGS_IRQ, so use PCIe interrupt 0. + */ + if (!(le16_to_cpu(pcie->bridge.pcie_conf.rootctl) & PCI_EXP_RTCTL_PMEIE)) + return; + + if (generic_handle_domain_irq(pcie->irq_domain, 0) == -EINVAL) + dev_err_ratelimited(&pcie->pdev->dev, "unhandled PME IRQ\n"); + } +} + static void advk_pcie_handle_msi(struct advk_pcie *pcie) { u32 msi_val, msi_mask, msi_status, msi_idx; @@ -1478,17 +1495,9 @@ static void advk_pcie_handle_int(struct advk_pcie *pcie) isr1_mask = advk_readl(pcie, PCIE_ISR1_MASK_REG); isr1_status = isr1_val & ((~isr1_mask) & PCIE_ISR1_ALL_MASK); - /* Process PME interrupt */ - if (isr0_status & PCIE_MSG_PM_PME_MASK) { - /* - * Do not clear PME interrupt bit in ISR0, it is cleared by IRQ - * receiver by writing to the PCI_EXP_RTSTA register of emulated - * root bridge. Aardvark HW returns zero for PCI_EXP_FLAGS_IRQ, - * so use PCIe interrupt 0. - */ - if (generic_handle_domain_irq(pcie->irq_domain, 0) == -EINVAL) - dev_err_ratelimited(&pcie->pdev->dev, "unhandled PME IRQ\n"); - } + /* Process PME interrupt as the first one to do not miss PME requester id */ + if (isr0_status & PCIE_MSG_PM_PME_MASK) + advk_pcie_handle_pme(pcie); /* Process ERR interrupt */ if (isr0_status & PCIE_ISR0_ERR_MASK) {