Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757831AbcCaRce (ORCPT ); Thu, 31 Mar 2016 13:32:34 -0400 Received: from mail-wm0-f43.google.com ([74.125.82.43]:37116 "EHLO mail-wm0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757957AbcCaRb5 (ORCPT ); Thu, 31 Mar 2016 13:31:57 -0400 From: Srinivas Kandagatla To: Tejun Heo , linux-ide@vger.kernel.org Cc: Rob Herring , Andy Gross , Hans de Goede , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-soc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, jmaggard10@gmail.com, Srinivas Kandagatla Subject: [PATCH v2 2/3] ata: ahci-platform: Add ports-implemented DT bindings. Date: Thu, 31 Mar 2016 18:31:39 +0100 Message-Id: <1459445500-9071-3-git-send-email-srinivas.kandagatla@linaro.org> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1459445500-9071-1-git-send-email-srinivas.kandagatla@linaro.org> References: <1459445500-9071-1-git-send-email-srinivas.kandagatla@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2151 Lines: 49 On some SOCs PORTS_IMPL register value is never programmed by the firmware and left at zero value. Which means that no sata ports are available for software. AHCI driver used to cope up with this by fabricating the port_map if the PORTS_IMPL register is read zero, but recent patch broke this workaround as zero value was valid for NVMe disks. This patch adds ports-implemented DT bindings as workaround for this issue in a way that DT can can override the PORTS_IMPL register in cases where the firmware did not program it already. Fixes: 566d1827df2e ("libata: disable forced PORTS_IMPL for >= AHCI 1.3) Signed-off-by: Srinivas Kandagatla --- Documentation/devicetree/bindings/ata/ahci-platform.txt | 4 ++++ drivers/ata/ahci_platform.c | 3 +++ 2 files changed, 7 insertions(+) diff --git a/Documentation/devicetree/bindings/ata/ahci-platform.txt b/Documentation/devicetree/bindings/ata/ahci-platform.txt index 30df832..87adfb2 100644 --- a/Documentation/devicetree/bindings/ata/ahci-platform.txt +++ b/Documentation/devicetree/bindings/ata/ahci-platform.txt @@ -32,6 +32,10 @@ Optional properties: - target-supply : regulator for SATA target power - phys : reference to the SATA PHY node - phy-names : must be "sata-phy" +- ports-implemented : Mask that indicates which ports that the HBA supports + are available for software to use. Useful if PORTS_IMPL + is not programmed by the BIOS, which is true with + some embedded SOC's. Required properties when using sub-nodes: - #address-cells : number of cells to encode an address diff --git a/drivers/ata/ahci_platform.c b/drivers/ata/ahci_platform.c index 4044233..62a04c8 100644 --- a/drivers/ata/ahci_platform.c +++ b/drivers/ata/ahci_platform.c @@ -51,6 +51,9 @@ static int ahci_probe(struct platform_device *pdev) if (rc) return rc; + of_property_read_u32(dev->of_node, + "ports-implemented", &hpriv->force_port_map); + if (of_device_is_compatible(dev->of_node, "hisilicon,hisi-ahci")) hpriv->flags |= AHCI_HFLAG_NO_FBS | AHCI_HFLAG_NO_NCQ; -- 2.5.0