From patchwork Tue Sep 27 14:19:19 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: 12990686 X-Patchwork-Delegate: lorenzo.pieralisi@arm.com 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 EE310C6FA83 for ; Tue, 27 Sep 2022 14:20:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230444AbiI0OUG (ORCPT ); Tue, 27 Sep 2022 10:20:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53330 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232057AbiI0OTy (ORCPT ); Tue, 27 Sep 2022 10:19:54 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3D643979FF for ; Tue, 27 Sep 2022 07:19:40 -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 7229EB81C01 for ; Tue, 27 Sep 2022 14:19:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8122FC433C1; Tue, 27 Sep 2022 14:19:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1664288377; bh=PUps/ldFkt1/yI6ZmwNvDNq7YAuTSGdZNC88IA2kSQk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YY7vZap89PBZyec+jMI/NGAhNvUYS9qfnkV7j3mcoBw/lfgS9yHkMvQ5SFGDOVqwH I6L+zLrrMY9JKRxBuBiqy0IJjLzpAqHmAKVEP3eU2QXHs6FjHcTZxwK10L3SZr0gTW oF/U4kzwL8lY0/zzvLwGGIyMh9mx8GLPuRO1QwUdxfkQGn54aN1SvCeft0adKCxpYC aYS1FoA5koY7GS/LUteWRKL8p1IxJ38bmuXHzgIDga/FHsv8GwOgk+PW7jCf7b1Q8T eHUQs/ZqYjHChb8846B4C07EJ6Tv/cIiH9da1IUqp+5dZxLe1PaO3m1wuOD+7hK7wN xSRoiPiXHxxGg== From: =?utf-8?q?Marek_Beh=C3=BAn?= To: Lorenzo Pieralisi Cc: Bjorn Helgaas , Gregory CLEMENT , pali@kernel.org, =?utf-8?q?K?= =?utf-8?q?rzysztof_Wilczy=C5=84ski?= , linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, =?utf-8?q?Marek_Beh=C3=BAn?= Subject: [PATCH v2 03/10] PCI: aardvark: Send Set_Slot_Power_Limit message Date: Tue, 27 Sep 2022 16:19:19 +0200 Message-Id: <20220927141926.8895-4-kabel@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220927141926.8895-1-kabel@kernel.org> References: <20220927141926.8895-1-kabel@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org From: Pali Rohár Emulate Slot PowerLimit Scale and Value bits in the Slot Capabilities register of the emulated bridge and if slot power limit value is defined, send that Set_Slot_Power_Limit message via Message Generation Control Register in Link Up handler on link up event. Slot power limit value is read from device-tree property 'slot-power-limit-milliwatt'. If this property is not specified, we treat it as "Slot Capabilities register has not yet been initialized". According to PCIe Base specification 3.0, when transitioning from a non-DL_Up Status to a DL_Up Status, the Port must initiate the transmission of a Set_Slot_Power_Limit Message to the other component on the Link to convey the value programmed in the Slot Power Limit Scale and Value fields of the Slot Capabilities register. This transmission is optional if the Slot Capabilities register has not yet been initialized. Signed-off-by: Pali Rohár Signed-off-by: Marek Behún --- drivers/pci/controller/pci-aardvark.c | 51 ++++++++++++++++++++++++--- 1 file changed, 47 insertions(+), 4 deletions(-) diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c index 31da28ebc5d1..03e318bc171f 100644 --- a/drivers/pci/controller/pci-aardvark.c +++ b/drivers/pci/controller/pci-aardvark.c @@ -213,6 +213,11 @@ enum { }; #define VENDOR_ID_REG (LMI_BASE_ADDR + 0x44) +#define PME_MSG_GEN_CTRL (LMI_BASE_ADDR + 0x220) +#define SEND_SET_SLOT_POWER_LIMIT BIT(13) +#define SEND_PME_TURN_OFF BIT(14) +#define SLOT_POWER_LIMIT_DATA_SHIFT 16 +#define SLOT_POWER_LIMIT_DATA_MASK GENMASK(25, 16) /* PCIe core controller registers */ #define CTRL_CORE_BASE_ADDR 0x18000 @@ -285,6 +290,8 @@ struct advk_pcie { raw_spinlock_t msi_irq_lock; DECLARE_BITMAP(msi_used, MSI_IRQ_NUM); struct mutex msi_used_lock; + u8 slot_power_limit_value; + u8 slot_power_limit_scale; int link_gen; bool link_was_up; struct timer_list link_irq_timer; @@ -317,8 +324,9 @@ static inline bool advk_pcie_link_up(struct advk_pcie *pcie) { /* check if LTSSM is in normal operation - some L* state */ u8 ltssm_state = advk_pcie_ltssm_state(pcie); + u16 slotsta, slotctl; + u32 slotpwr, val; bool link_is_up; - u16 slotsta; link_is_up = ltssm_state >= LTSSM_L0 && ltssm_state < LTSSM_DISABLED; @@ -332,6 +340,27 @@ static inline bool advk_pcie_link_up(struct advk_pcie *pcie) pcie->bridge.pcie_conf.slotsta = cpu_to_le16(slotsta); mod_timer(&pcie->link_irq_timer, jiffies + 1); + + /* + * According to PCIe Base specification 3.0, when transitioning + * from a non-DL_Up Status to a DL_Up Status, the Port must + * initiate the transmission of a Set_Slot_Power_Limit Message + * to the other component on the Link to convey the value + * programmed in the Slot Power Limit Scale and Value fields of + * the Slot Capabilities register. This transmission is optional + * if the Slot Capabilities register has not yet been + * initialized. + */ + slotctl = le16_to_cpu(pcie->bridge.pcie_conf.slotctl); + slotpwr = FIELD_GET(PCI_EXP_SLTCAP_SPLV | PCI_EXP_SLTCAP_SPLS, + le32_to_cpu(pcie->bridge.pcie_conf.slotcap)); + if (!(slotctl & PCI_EXP_SLTCTL_ASPL_DISABLE) && slotpwr) { + val = advk_readl(pcie, PME_MSG_GEN_CTRL); + val &= ~SLOT_POWER_LIMIT_DATA_MASK; + val |= slotpwr << SLOT_POWER_LIMIT_DATA_SHIFT; + val |= SEND_SET_SLOT_POWER_LIMIT; + advk_writel(pcie, val, PME_MSG_GEN_CTRL); + } } return link_is_up; @@ -944,8 +973,9 @@ advk_pci_bridge_emul_pcie_conf_write(struct pci_bridge_emul *bridge, case PCI_EXP_SLTCTL: { u16 slotctl = le16_to_cpu(bridge->pcie_conf.slotctl); - /* Only emulation of HPIE and DLLSCE bits is provided */ - slotctl &= PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_DLLSCE; + /* Only emulation of HPIE, DLLSCE and ASPLD bits is provided */ + slotctl &= PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_DLLSCE | + PCI_EXP_SLTCTL_ASPL_DISABLE; bridge->pcie_conf.slotctl = cpu_to_le16(slotctl); break; } @@ -1109,9 +1139,13 @@ static int advk_sw_pci_bridge_init(struct advk_pcie *pcie) * Set physical slot number to 1 since there is only one port and zero * value is reserved for ports within the same silicon as Root Port * which is not our case. + * + * Set slot power limit. */ slotcap = PCI_EXP_SLTCAP_NCCS | PCI_EXP_SLTCAP_HPC | - FIELD_PREP(PCI_EXP_SLTCAP_PSN, 1); + FIELD_PREP(PCI_EXP_SLTCAP_PSN, 1) | + FIELD_PREP(PCI_EXP_SLTCAP_SPLV, pcie->slot_power_limit_value) | + FIELD_PREP(PCI_EXP_SLTCAP_SPLS, pcie->slot_power_limit_scale); bridge->pcie_conf.slotcap = cpu_to_le32(slotcap); bridge->pcie_conf.slotsta = cpu_to_le16(PCI_EXP_SLTSTA_PDS); @@ -1837,6 +1871,7 @@ static int advk_pcie_probe(struct platform_device *pdev) struct advk_pcie *pcie; struct pci_host_bridge *bridge; struct resource_entry *entry; + u32 slot_power_limit; int ret, irq; bridge = devm_pci_alloc_host_bridge(dev, sizeof(struct advk_pcie)); @@ -1957,6 +1992,14 @@ static int advk_pcie_probe(struct platform_device *pdev) else pcie->link_gen = ret; + slot_power_limit = of_pci_get_slot_power_limit(dev->of_node, + &pcie->slot_power_limit_value, + &pcie->slot_power_limit_scale); + if (slot_power_limit) + dev_info(dev, "Slot Power Limit: %u.%uW\n", + slot_power_limit / 1000, + (slot_power_limit / 100) % 10); + ret = advk_pcie_setup_phy(pcie); if (ret) return ret;