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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 223ACC433EF for ; Fri, 3 Jun 2022 17:45:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345039AbiFCRpa (ORCPT ); Fri, 3 Jun 2022 13:45:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56714 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345157AbiFCRox (ORCPT ); Fri, 3 Jun 2022 13:44:53 -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 7B1E6541A0; Fri, 3 Jun 2022 10:42:46 -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 15209B823B2; Fri, 3 Jun 2022 17:42:45 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 790C1C385A9; Fri, 3 Jun 2022 17:42:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1654278163; bh=2goF6wvu7jWNv1rrIlegSjNUxSQ+fEHnI55FfXfOndo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=knDbfsOLXAq5guGo0AZZ+d/sFRkt84VRSKymwv/tqD2berZdZLLKZ/fuc1GdgK1r0 VG0ZcilOs2oq3A3ygMb4ozA3iEJbvK4VnZkVHYPx7cKnHn24TlezSBlhxiMsZHLpPF /Z1DXTTMN1wr5GkstqZ1J2Fz6krdQplA3oRqHO4Q= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mika Westerberg , "From: Andy Shevchenko" , Wolfram Sang , Sasha Levin Subject: [PATCH 4.19 09/30] i2c: ismt: Provide a DMA buffer for Interrupt Cause Logging Date: Fri, 3 Jun 2022 19:39:37 +0200 Message-Id: <20220603173815.368098182@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220603173815.088143764@linuxfoundation.org> References: <20220603173815.088143764@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Mika Westerberg [ Upstream commit 17a0f3acdc6ec8b89ad40f6e22165a4beee25663 ] Before sending a MSI the hardware writes information pertinent to the interrupt cause to a memory location pointed by SMTICL register. This memory holds three double words where the least significant bit tells whether the interrupt cause of master/target/error is valid. The driver does not use this but we need to set it up because otherwise it will perform DMA write to the default address (0) and this will cause an IOMMU fault such as below: DMAR: DRHD: handling fault status reg 2 DMAR: [DMA Write] Request device [00:12.0] PASID ffffffff fault addr 0 [fault reason 05] PTE Write access is not set To prevent this from happening, provide a proper DMA buffer for this that then gets mapped by the IOMMU accordingly. Signed-off-by: Mika Westerberg Reviewed-by: From: Andy Shevchenko Signed-off-by: Wolfram Sang Signed-off-by: Sasha Levin --- drivers/i2c/busses/i2c-ismt.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/drivers/i2c/busses/i2c-ismt.c b/drivers/i2c/busses/i2c-ismt.c index 0d1c3ec8cb40..80796061102f 100644 --- a/drivers/i2c/busses/i2c-ismt.c +++ b/drivers/i2c/busses/i2c-ismt.c @@ -80,6 +80,7 @@ #define ISMT_DESC_ENTRIES 2 /* number of descriptor entries */ #define ISMT_MAX_RETRIES 3 /* number of SMBus retries to attempt */ +#define ISMT_LOG_ENTRIES 3 /* number of interrupt cause log entries */ /* Hardware Descriptor Constants - Control Field */ #define ISMT_DESC_CWRL 0x01 /* Command/Write Length */ @@ -173,6 +174,8 @@ struct ismt_priv { u8 head; /* ring buffer head pointer */ struct completion cmp; /* interrupt completion */ u8 buffer[I2C_SMBUS_BLOCK_MAX + 16]; /* temp R/W data buffer */ + dma_addr_t log_dma; + u32 *log; }; /** @@ -406,6 +409,9 @@ static int ismt_access(struct i2c_adapter *adap, u16 addr, memset(desc, 0, sizeof(struct ismt_desc)); desc->tgtaddr_rw = ISMT_DESC_ADDR_RW(addr, read_write); + /* Always clear the log entries */ + memset(priv->log, 0, ISMT_LOG_ENTRIES * sizeof(u32)); + /* Initialize common control bits */ if (likely(pci_dev_msi_enabled(priv->pci_dev))) desc->control = ISMT_DESC_INT | ISMT_DESC_FAIR; @@ -695,6 +701,8 @@ static void ismt_hw_init(struct ismt_priv *priv) /* initialize the Master Descriptor Base Address (MDBA) */ writeq(priv->io_rng_dma, priv->smba + ISMT_MSTR_MDBA); + writeq(priv->log_dma, priv->smba + ISMT_GR_SMTICL); + /* initialize the Master Control Register (MCTRL) */ writel(ISMT_MCTRL_MEIE, priv->smba + ISMT_MSTR_MCTRL); @@ -784,6 +792,12 @@ static int ismt_dev_init(struct ismt_priv *priv) priv->head = 0; init_completion(&priv->cmp); + priv->log = dmam_alloc_coherent(&priv->pci_dev->dev, + ISMT_LOG_ENTRIES * sizeof(u32), + &priv->log_dma, GFP_KERNEL); + if (!priv->log) + return -ENOMEM; + return 0; } -- 2.35.1