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=-13.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 7EBC0C43214 for ; Thu, 26 Aug 2021 01:36:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 600BA60F45 for ; Thu, 26 Aug 2021 01:36:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236264AbhHZBgy (ORCPT ); Wed, 25 Aug 2021 21:36:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52728 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235847AbhHZBgx (ORCPT ); Wed, 25 Aug 2021 21:36:53 -0400 Received: from mail-pl1-x635.google.com (mail-pl1-x635.google.com [IPv6:2607:f8b0:4864:20::635]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A8FAFC0613CF for ; Wed, 25 Aug 2021 18:36:05 -0700 (PDT) Received: by mail-pl1-x635.google.com with SMTP id n12so727800plk.10 for ; Wed, 25 Aug 2021 18:36:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=intel-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=RG0H94xd0UOZq/hx1Z7vIDohBIJ9x0ffRWEXS/+MBwQ=; b=VOUhqeYZMuitOX4NK4CEGVhmjQH5aQda9PVoc3zOBzkP9umHbTNzw11+Khc6cdgixJ kNlGI+tJIbIIr7kX3vEkbo0b0FBRJYpP+Ryx+Z5KQ0B28Kp+i4c9hapJ+4/IqMFR5XtS EKV8+Ji91+Er7NmdF5czVuw7+w8AycAmTnTfVA3hyAxGMFLRhBZ/5GJEZioFcPTZ0EBJ nt/nYemT1IXEfu8a6A2JSgfCTAG3XFQXtXus6yr2d0i6VeFRtROcUaABT/rCwz5Y1hHu KF0INEDC73PlqBhHdYgV4ojvXBvL7upl0bTYJf8H6SqJLeZJPjCJMw1i78+197LE0FWf FTHQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=RG0H94xd0UOZq/hx1Z7vIDohBIJ9x0ffRWEXS/+MBwQ=; b=EoYuUFhSxyxFqYT/abq1HWL04sJRfYGLiC1L1Lvz9hfedc3hRTteSlwHy5lMESMDbB WllcEMCACsdhhxkUm7gy6Vpyi2457F+Uu6rwu9baUdR18nBMs9WkX3fAR1RT9FdVgIf0 j80D6azfCp8EhyCT24e5x6bOGBuNjW8tiX4pRRw51ESCncj6UZspR+i67CIIcoIjwyhs lgrn8Pbzewkvnqoe9/xJSOEgAe17kyekX5U+aAze8XfpSFJJRjF3CZrY6W1OPZG4T7e3 /NV7xLcmDTgwdanuZTmy9FKozaTc53RfumzIum4sQT23KEKAsZ2GpZkur713YCpi7PsE hw2A== X-Gm-Message-State: AOAM5320Dog79EEjnOxa6nmrb/cF14M6944XTzRJEog8Z3COhtl3PT7h PoUMA8NN88eQWiGBkg8eLTVrK93fsteDWIxQEr+adg== X-Google-Smtp-Source: ABdhPJw2EQoMk+VkGKH34pT9dv8bAf98oQur3rF5nOSjeRaWUuBWEh6Lixalh4VzsNZ6ymIsfgB6HzEtEAoKy/jbEuQ= X-Received: by 2002:a17:902:ba90:b0:135:6709:705 with SMTP id k16-20020a170902ba9000b0013567090705mr1227850pls.79.1629941764989; Wed, 25 Aug 2021 18:36:04 -0700 (PDT) MIME-Version: 1.0 References: <20210803113134.2262882-1-iwona.winiarska@intel.com> <20210803113134.2262882-8-iwona.winiarska@intel.com> In-Reply-To: <20210803113134.2262882-8-iwona.winiarska@intel.com> From: Dan Williams Date: Wed, 25 Aug 2021 18:35:53 -0700 Message-ID: Subject: Re: [PATCH v2 07/15] peci: Add peci-aspeed controller driver To: Iwona Winiarska Cc: Linux Kernel Mailing List , openbmc@lists.ozlabs.org, Greg Kroah-Hartman , X86 ML , Device Tree , linux-aspeed@lists.ozlabs.org, Linux ARM , linux-hwmon@vger.kernel.org, Linux Doc Mailing List , Rob Herring , Joel Stanley , Andrew Jeffery , Jean Delvare , Guenter Roeck , Arnd Bergmann , Olof Johansson , Jonathan Corbet , Thomas Gleixner , Andy Lutomirski , Ingo Molnar , Borislav Petkov , Yazen Ghannam , Mauro Carvalho Chehab , Pierre-Louis Bossart , Tony Luck , Andy Shevchenko , Jae Hyun Yoo , Randy Dunlap , Zev Weiss , David Muller Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Aug 3, 2021 at 4:35 AM Iwona Winiarska wrote: > > From: Jae Hyun Yoo > > ASPEED AST24xx/AST25xx/AST26xx SoCs supports the PECI electrical > interface (a.k.a PECI wire). Maybe a one sentence blurb here and in the Kconfig reminding people why they should care if they have a PECI driver or not? > > Signed-off-by: Jae Hyun Yoo > Co-developed-by: Iwona Winiarska > Signed-off-by: Iwona Winiarska > Reviewed-by: Pierre-Louis Bossart > --- > MAINTAINERS | 9 + > drivers/peci/Kconfig | 6 + > drivers/peci/Makefile | 3 + > drivers/peci/controller/Kconfig | 16 + > drivers/peci/controller/Makefile | 3 + > drivers/peci/controller/peci-aspeed.c | 445 ++++++++++++++++++++++++++ > 6 files changed, 482 insertions(+) > create mode 100644 drivers/peci/controller/Kconfig > create mode 100644 drivers/peci/controller/Makefile > create mode 100644 drivers/peci/controller/peci-aspeed.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index d411974aaa5e..6e9d53ff68ab 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -2866,6 +2866,15 @@ S: Maintained > F: Documentation/hwmon/asc7621.rst > F: drivers/hwmon/asc7621.c > > +ASPEED PECI CONTROLLER > +M: Iwona Winiarska > +M: Jae Hyun Yoo > +L: linux-aspeed@lists.ozlabs.org (moderated for non-subscribers) > +L: openbmc@lists.ozlabs.org (moderated for non-subscribers) > +S: Supported > +F: Documentation/devicetree/bindings/peci/peci-aspeed.yaml > +F: drivers/peci/controller/peci-aspeed.c > + > ASPEED PINCTRL DRIVERS > M: Andrew Jeffery > L: linux-aspeed@lists.ozlabs.org (moderated for non-subscribers) > diff --git a/drivers/peci/Kconfig b/drivers/peci/Kconfig > index 71a4ad81225a..99279df97a78 100644 > --- a/drivers/peci/Kconfig > +++ b/drivers/peci/Kconfig > @@ -13,3 +13,9 @@ menuconfig PECI > > This support is also available as a module. If so, the module > will be called peci. > + > +if PECI > + > +source "drivers/peci/controller/Kconfig" > + > +endif # PECI > diff --git a/drivers/peci/Makefile b/drivers/peci/Makefile > index e789a354e842..926d8df15cbd 100644 > --- a/drivers/peci/Makefile > +++ b/drivers/peci/Makefile > @@ -3,3 +3,6 @@ > # Core functionality > peci-y := core.o > obj-$(CONFIG_PECI) += peci.o > + > +# Hardware specific bus drivers > +obj-y += controller/ > diff --git a/drivers/peci/controller/Kconfig b/drivers/peci/controller/Kconfig > new file mode 100644 > index 000000000000..6d48df08db1c > --- /dev/null > +++ b/drivers/peci/controller/Kconfig > @@ -0,0 +1,16 @@ > +# SPDX-License-Identifier: GPL-2.0-only > + > +config PECI_ASPEED > + tristate "ASPEED PECI support" > + depends on ARCH_ASPEED || COMPILE_TEST > + depends on OF > + depends on HAS_IOMEM > + help > + This option enables PECI controller driver for ASPEED AST2400, > + AST2500 and AST2600 SoCs. > + > + Say Y here if your system runs on ASPEED SoC and you are using it > + as BMC for Intel platform. > + > + This driver can also be built as a module. If so, the module will > + be called peci-aspeed. > diff --git a/drivers/peci/controller/Makefile b/drivers/peci/controller/Makefile > new file mode 100644 > index 000000000000..022c28ef1bf0 > --- /dev/null > +++ b/drivers/peci/controller/Makefile > @@ -0,0 +1,3 @@ > +# SPDX-License-Identifier: GPL-2.0-only > + > +obj-$(CONFIG_PECI_ASPEED) += peci-aspeed.o > diff --git a/drivers/peci/controller/peci-aspeed.c b/drivers/peci/controller/peci-aspeed.c > new file mode 100644 > index 000000000000..1d708c983749 > --- /dev/null > +++ b/drivers/peci/controller/peci-aspeed.c > @@ -0,0 +1,445 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +// Copyright (C) 2012-2017 ASPEED Technology Inc. > +// Copyright (c) 2018-2021 Intel Corporation Why different copyright capitalization? > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include Why is this included? > + > +/* ASPEED PECI Registers */ > +/* Control Register */ > +#define ASPEED_PECI_CTRL 0x00 > +#define ASPEED_PECI_CTRL_SAMPLING_MASK GENMASK(19, 16) > +#define ASPEED_PECI_CTRL_RD_MODE_MASK GENMASK(13, 12) > +#define ASPEED_PECI_CTRL_RD_MODE_DBG BIT(13) > +#define ASPEED_PECI_CTRL_RD_MODE_COUNT BIT(12) > +#define ASPEED_PECI_CTRL_CLK_SOURCE BIT(11) > +#define ASPEED_PECI_CTRL_CLK_DIV_MASK GENMASK(10, 8) > +#define ASPEED_PECI_CTRL_INVERT_OUT BIT(7) > +#define ASPEED_PECI_CTRL_INVERT_IN BIT(6) > +#define ASPEED_PECI_CTRL_BUS_CONTENTION_EN BIT(5) > +#define ASPEED_PECI_CTRL_PECI_EN BIT(4) > +#define ASPEED_PECI_CTRL_PECI_CLK_EN BIT(0) > + > +/* Timing Negotiation Register */ > +#define ASPEED_PECI_TIMING_NEGOTIATION 0x04 > +#define ASPEED_PECI_T_NEGO_MSG_MASK GENMASK(15, 8) > +#define ASPEED_PECI_T_NEGO_ADDR_MASK GENMASK(7, 0) > + > +/* Command Register */ > +#define ASPEED_PECI_CMD 0x08 > +#define ASPEED_PECI_CMD_PIN_MONITORING BIT(31) > +#define ASPEED_PECI_CMD_STS_MASK GENMASK(27, 24) > +#define ASPEED_PECI_CMD_STS_ADDR_T_NEGO 0x3 > +#define ASPEED_PECI_CMD_IDLE_MASK \ > + (ASPEED_PECI_CMD_STS_MASK | ASPEED_PECI_CMD_PIN_MONITORING) > +#define ASPEED_PECI_CMD_FIRE BIT(0) > + > +/* Read/Write Length Register */ > +#define ASPEED_PECI_RW_LENGTH 0x0c > +#define ASPEED_PECI_AW_FCS_EN BIT(31) > +#define ASPEED_PECI_RD_LEN_MASK GENMASK(23, 16) > +#define ASPEED_PECI_WR_LEN_MASK GENMASK(15, 8) > +#define ASPEED_PECI_TARGET_ADDR_MASK GENMASK(7, 0) > + > +/* Expected FCS Data Register */ > +#define ASPEED_PECI_EXPECTED_FCS 0x10 > +#define ASPEED_PECI_EXPECTED_RD_FCS_MASK GENMASK(23, 16) > +#define ASPEED_PECI_EXPECTED_AW_FCS_AUTO_MASK GENMASK(15, 8) > +#define ASPEED_PECI_EXPECTED_WR_FCS_MASK GENMASK(7, 0) > + > +/* Captured FCS Data Register */ > +#define ASPEED_PECI_CAPTURED_FCS 0x14 > +#define ASPEED_PECI_CAPTURED_RD_FCS_MASK GENMASK(23, 16) > +#define ASPEED_PECI_CAPTURED_WR_FCS_MASK GENMASK(7, 0) > + > +/* Interrupt Register */ > +#define ASPEED_PECI_INT_CTRL 0x18 > +#define ASPEED_PECI_TIMING_NEGO_SEL_MASK GENMASK(31, 30) > +#define ASPEED_PECI_1ST_BIT_OF_ADDR_NEGO 0 > +#define ASPEED_PECI_2ND_BIT_OF_ADDR_NEGO 1 > +#define ASPEED_PECI_MESSAGE_NEGO 2 > +#define ASPEED_PECI_INT_MASK GENMASK(4, 0) > +#define ASPEED_PECI_INT_BUS_TIMEOUT BIT(4) > +#define ASPEED_PECI_INT_BUS_CONTENTION BIT(3) > +#define ASPEED_PECI_INT_WR_FCS_BAD BIT(2) > +#define ASPEED_PECI_INT_WR_FCS_ABORT BIT(1) > +#define ASPEED_PECI_INT_CMD_DONE BIT(0) > + > +/* Interrupt Status Register */ > +#define ASPEED_PECI_INT_STS 0x1c > +#define ASPEED_PECI_INT_TIMING_RESULT_MASK GENMASK(29, 16) > + /* bits[4..0]: Same bit fields in the 'Interrupt Register' */ > + > +/* Rx/Tx Data Buffer Registers */ > +#define ASPEED_PECI_WR_DATA0 0x20 > +#define ASPEED_PECI_WR_DATA1 0x24 > +#define ASPEED_PECI_WR_DATA2 0x28 > +#define ASPEED_PECI_WR_DATA3 0x2c > +#define ASPEED_PECI_RD_DATA0 0x30 > +#define ASPEED_PECI_RD_DATA1 0x34 > +#define ASPEED_PECI_RD_DATA2 0x38 > +#define ASPEED_PECI_RD_DATA3 0x3c > +#define ASPEED_PECI_WR_DATA4 0x40 > +#define ASPEED_PECI_WR_DATA5 0x44 > +#define ASPEED_PECI_WR_DATA6 0x48 > +#define ASPEED_PECI_WR_DATA7 0x4c > +#define ASPEED_PECI_RD_DATA4 0x50 > +#define ASPEED_PECI_RD_DATA5 0x54 > +#define ASPEED_PECI_RD_DATA6 0x58 > +#define ASPEED_PECI_RD_DATA7 0x5c > +#define ASPEED_PECI_DATA_BUF_SIZE_MAX 32 > + > +/* Timing Negotiation */ > +#define ASPEED_PECI_RD_SAMPLING_POINT_DEFAULT 8 > +#define ASPEED_PECI_RD_SAMPLING_POINT_MAX (BIT(4) - 1) > +#define ASPEED_PECI_CLK_DIV_DEFAULT 0 > +#define ASPEED_PECI_CLK_DIV_MAX (BIT(3) - 1) > +#define ASPEED_PECI_MSG_TIMING_DEFAULT 1 > +#define ASPEED_PECI_MSG_TIMING_MAX (BIT(8) - 1) > +#define ASPEED_PECI_ADDR_TIMING_DEFAULT 1 > +#define ASPEED_PECI_ADDR_TIMING_MAX (BIT(8) - 1) > + > +/* Timeout */ > +#define ASPEED_PECI_IDLE_CHECK_TIMEOUT_US (50 * USEC_PER_MSEC) > +#define ASPEED_PECI_IDLE_CHECK_INTERVAL_US (10 * USEC_PER_MSEC) > +#define ASPEED_PECI_CMD_TIMEOUT_MS_DEFAULT (1000) > +#define ASPEED_PECI_CMD_TIMEOUT_MS_MAX (1000) > + > +struct aspeed_peci { > + struct peci_controller *controller; > + struct device *dev; > + void __iomem *base; > + struct clk *clk; > + struct reset_control *rst; > + int irq; > + spinlock_t lock; /* to sync completion status handling */ > + struct completion xfer_complete; > + u32 status; > + u32 cmd_timeout_ms; > + u32 msg_timing; > + u32 addr_timing; > + u32 rd_sampling_point; > + u32 clk_div; > +}; > + > +static void aspeed_peci_init_regs(struct aspeed_peci *priv) > +{ > + u32 val; > + > + val = FIELD_PREP(ASPEED_PECI_CTRL_CLK_DIV_MASK, ASPEED_PECI_CLK_DIV_DEFAULT); > + val |= ASPEED_PECI_CTRL_PECI_CLK_EN; > + writel(val, priv->base + ASPEED_PECI_CTRL); > + /* > + * Timing negotiation period setting. > + * The unit of the programmed value is 4 times of PECI clock period. > + */ > + val = FIELD_PREP(ASPEED_PECI_T_NEGO_MSG_MASK, priv->msg_timing); > + val |= FIELD_PREP(ASPEED_PECI_T_NEGO_ADDR_MASK, priv->addr_timing); > + writel(val, priv->base + ASPEED_PECI_TIMING_NEGOTIATION); > + > + /* Clear interrupts */ > + val = readl(priv->base + ASPEED_PECI_INT_STS) | ASPEED_PECI_INT_MASK; > + writel(val, priv->base + ASPEED_PECI_INT_STS); > + > + /* Set timing negotiation mode and enable interrupts */ > + val = FIELD_PREP(ASPEED_PECI_TIMING_NEGO_SEL_MASK, ASPEED_PECI_1ST_BIT_OF_ADDR_NEGO); > + val |= ASPEED_PECI_INT_MASK; > + writel(val, priv->base + ASPEED_PECI_INT_CTRL); > + > + val = FIELD_PREP(ASPEED_PECI_CTRL_SAMPLING_MASK, priv->rd_sampling_point); > + val |= FIELD_PREP(ASPEED_PECI_CTRL_CLK_DIV_MASK, priv->clk_div); > + val |= ASPEED_PECI_CTRL_PECI_EN; > + val |= ASPEED_PECI_CTRL_PECI_CLK_EN; > + writel(val, priv->base + ASPEED_PECI_CTRL); > +} > + > +static inline int aspeed_peci_check_idle(struct aspeed_peci *priv) > +{ > + u32 cmd_sts = readl(priv->base + ASPEED_PECI_CMD); > + > + if (FIELD_GET(ASPEED_PECI_CMD_STS_MASK, cmd_sts) == ASPEED_PECI_CMD_STS_ADDR_T_NEGO) > + aspeed_peci_init_regs(priv); > + > + return readl_poll_timeout(priv->base + ASPEED_PECI_CMD, > + cmd_sts, > + !(cmd_sts & ASPEED_PECI_CMD_IDLE_MASK), > + ASPEED_PECI_IDLE_CHECK_INTERVAL_US, > + ASPEED_PECI_IDLE_CHECK_TIMEOUT_US); > +} > + > +static int aspeed_peci_xfer(struct peci_controller *controller, > + u8 addr, struct peci_request *req) > +{ > + struct aspeed_peci *priv = dev_get_drvdata(controller->dev.parent); > + unsigned long flags, timeout = msecs_to_jiffies(priv->cmd_timeout_ms); > + u32 peci_head; > + int ret; > + > + if (req->tx.len > ASPEED_PECI_DATA_BUF_SIZE_MAX || > + req->rx.len > ASPEED_PECI_DATA_BUF_SIZE_MAX) > + return -EINVAL; > + > + /* Check command sts and bus idle state */ > + ret = aspeed_peci_check_idle(priv); > + if (ret) > + return ret; /* -ETIMEDOUT */ > + > + spin_lock_irqsave(&priv->lock, flags); > + reinit_completion(&priv->xfer_complete); > + > + peci_head = FIELD_PREP(ASPEED_PECI_TARGET_ADDR_MASK, addr) | > + FIELD_PREP(ASPEED_PECI_WR_LEN_MASK, req->tx.len) | > + FIELD_PREP(ASPEED_PECI_RD_LEN_MASK, req->rx.len); > + > + writel(peci_head, priv->base + ASPEED_PECI_RW_LENGTH); > + > + memcpy_toio(priv->base + ASPEED_PECI_WR_DATA0, req->tx.buf, min_t(u8, req->tx.len, 16)); > + if (req->tx.len > 16) > + memcpy_toio(priv->base + ASPEED_PECI_WR_DATA4, req->tx.buf + 16, > + req->tx.len - 16); > + > + dev_dbg(priv->dev, "HEAD : 0x%08x\n", peci_head); > + print_hex_dump_bytes("TX : ", DUMP_PREFIX_NONE, req->tx.buf, req->tx.len); On CONFIG_DYNAMIC_DEBUG=n builds the kernel will do all the work of reading through this buffer, but skip emitting it. Are you sure you want to pay that overhead for every transaction? > + > + priv->status = 0; > + writel(ASPEED_PECI_CMD_FIRE, priv->base + ASPEED_PECI_CMD); > + spin_unlock_irqrestore(&priv->lock, flags); > + > + ret = wait_for_completion_interruptible_timeout(&priv->xfer_complete, timeout); spin_lock_irqsave() says "I don't know if interrupts are disabled already, so I'll save the state, whatever it is, and restore later" wait_for_completion_interruptible_timeout() says "I know I am in a sleepable context where interrupts are enabled" So, one of those is wrong, i.e. should it be spin_{lock,unlock}_irq()? > + if (ret < 0) > + return ret; > + > + if (ret == 0) { > + dev_dbg(priv->dev, "Timeout waiting for a response!\n"); > + return -ETIMEDOUT; > + } > + > + spin_lock_irqsave(&priv->lock, flags); > + > + writel(0, priv->base + ASPEED_PECI_CMD); > + > + if (priv->status != ASPEED_PECI_INT_CMD_DONE) { > + spin_unlock_irqrestore(&priv->lock, flags); > + dev_dbg(priv->dev, "No valid response!\n"); > + return -EIO; > + } > + > + spin_unlock_irqrestore(&priv->lock, flags); > + > + memcpy_fromio(req->rx.buf, priv->base + ASPEED_PECI_RD_DATA0, min_t(u8, req->rx.len, 16)); > + if (req->rx.len > 16) > + memcpy_fromio(req->rx.buf + 16, priv->base + ASPEED_PECI_RD_DATA4, > + req->rx.len - 16); > + > + print_hex_dump_bytes("RX : ", DUMP_PREFIX_NONE, req->rx.buf, req->rx.len); > + > + return 0; > +} > + > +static irqreturn_t aspeed_peci_irq_handler(int irq, void *arg) > +{ > + struct aspeed_peci *priv = arg; > + u32 status; > + > + spin_lock(&priv->lock); > + status = readl(priv->base + ASPEED_PECI_INT_STS); > + writel(status, priv->base + ASPEED_PECI_INT_STS); > + priv->status |= (status & ASPEED_PECI_INT_MASK); > + > + /* > + * In most cases, interrupt bits will be set one by one but also note > + * that multiple interrupt bits could be set at the same time. > + */ > + if (status & ASPEED_PECI_INT_BUS_TIMEOUT) > + dev_dbg_ratelimited(priv->dev, "ASPEED_PECI_INT_BUS_TIMEOUT\n"); > + > + if (status & ASPEED_PECI_INT_BUS_CONTENTION) > + dev_dbg_ratelimited(priv->dev, "ASPEED_PECI_INT_BUS_CONTENTION\n"); > + > + if (status & ASPEED_PECI_INT_WR_FCS_BAD) > + dev_dbg_ratelimited(priv->dev, "ASPEED_PECI_INT_WR_FCS_BAD\n"); > + > + if (status & ASPEED_PECI_INT_WR_FCS_ABORT) > + dev_dbg_ratelimited(priv->dev, "ASPEED_PECI_INT_WR_FCS_ABORT\n"); Are you sure these would not be better as tracepoints? If you're debugging an interrupt related failure, the ratelimiting might get in your way when you really need to know when one of these error interrupts fire relative to another event. > + > + /* > + * All commands should be ended up with a ASPEED_PECI_INT_CMD_DONE bit > + * set even in an error case. > + */ > + if (status & ASPEED_PECI_INT_CMD_DONE) > + complete(&priv->xfer_complete); Hmm, no need to check if there was a sequencing error, like a command was never submitted? > + > + spin_unlock(&priv->lock); > + > + return IRQ_HANDLED; > +} > + > +static void aspeed_peci_property_sanitize(struct device *dev, const char *propname, > + u32 min, u32 max, u32 default_val, u32 *propval) > +{ > + u32 val; > + int ret; > + > + ret = device_property_read_u32(dev, propname, &val); > + if (ret) { > + val = default_val; > + } else if (val > max || val < min) { > + dev_warn(dev, "Invalid %s: %u, falling back to: %u\n", > + propname, val, default_val); > + > + val = default_val; > + } > + > + *propval = val; > +} > + > +static void aspeed_peci_property_setup(struct aspeed_peci *priv) > +{ > + aspeed_peci_property_sanitize(priv->dev, "aspeed,clock-divider", > + 0, ASPEED_PECI_CLK_DIV_MAX, > + ASPEED_PECI_CLK_DIV_DEFAULT, &priv->clk_div); > + aspeed_peci_property_sanitize(priv->dev, "aspeed,msg-timing", > + 0, ASPEED_PECI_MSG_TIMING_MAX, > + ASPEED_PECI_MSG_TIMING_DEFAULT, &priv->msg_timing); > + aspeed_peci_property_sanitize(priv->dev, "aspeed,addr-timing", > + 0, ASPEED_PECI_ADDR_TIMING_MAX, > + ASPEED_PECI_ADDR_TIMING_DEFAULT, &priv->addr_timing); > + aspeed_peci_property_sanitize(priv->dev, "aspeed,rd-sampling-point", > + 0, ASPEED_PECI_RD_SAMPLING_POINT_MAX, > + ASPEED_PECI_RD_SAMPLING_POINT_DEFAULT, > + &priv->rd_sampling_point); > + aspeed_peci_property_sanitize(priv->dev, "cmd-timeout-ms", > + 1, ASPEED_PECI_CMD_TIMEOUT_MS_MAX, > + ASPEED_PECI_CMD_TIMEOUT_MS_DEFAULT, &priv->cmd_timeout_ms); > +} > + > +static struct peci_controller_ops aspeed_ops = { > + .xfer = aspeed_peci_xfer, > +}; > + > +static void aspeed_peci_reset_control_release(void *data) > +{ > + reset_control_assert(data); > +} > + > +int aspeed_peci_reset_control_deassert(struct device *dev, struct reset_control *rst) I'd recommend naming this devm_aspeed_peci_reset_control_deassert(), because I came looking here from reading probe for why there was no reassertion of reset on driver ->remove(). > +{ > + int ret; > + > + ret = reset_control_deassert(rst); > + if (ret) > + return ret; > + > + return devm_add_action_or_reset(dev, aspeed_peci_reset_control_release, rst); > +} > + > +static void aspeed_peci_clk_release(void *data) > +{ > + clk_disable_unprepare(data); > +} > + > +static int aspeed_peci_clk_enable(struct device *dev, struct clk *clk) ...ditto on the devm prefix, just to speed readability. > +{ > + int ret; > + > + ret = clk_prepare_enable(clk); > + if (ret) > + return ret; > + > + return devm_add_action_or_reset(dev, aspeed_peci_clk_release, clk); > +} > + > +static int aspeed_peci_probe(struct platform_device *pdev) > +{ > + struct peci_controller *controller; > + struct aspeed_peci *priv; > + int ret; > + > + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); > + if (!priv) > + return -ENOMEM; > + > + priv->dev = &pdev->dev; > + dev_set_drvdata(priv->dev, priv); > + > + priv->base = devm_platform_ioremap_resource(pdev, 0); > + if (IS_ERR(priv->base)) > + return PTR_ERR(priv->base); > + > + priv->irq = platform_get_irq(pdev, 0); > + if (!priv->irq) > + return priv->irq; > + > + ret = devm_request_irq(&pdev->dev, priv->irq, aspeed_peci_irq_handler, > + 0, "peci-aspeed", priv); > + if (ret) > + return ret; > + > + init_completion(&priv->xfer_complete); > + spin_lock_init(&priv->lock); > + > + priv->rst = devm_reset_control_get(&pdev->dev, NULL); > + if (IS_ERR(priv->rst)) > + return dev_err_probe(priv->dev, PTR_ERR(priv->rst), > + "failed to get reset control\n"); > + > + ret = aspeed_peci_reset_control_deassert(priv->dev, priv->rst); > + if (ret) > + return dev_err_probe(priv->dev, ret, "cannot deassert reset control\n"); > + > + priv->clk = devm_clk_get(priv->dev, NULL); > + if (IS_ERR(priv->clk)) > + return dev_err_probe(priv->dev, PTR_ERR(priv->clk), "failed to get clk\n"); > + > + ret = aspeed_peci_clk_enable(priv->dev, priv->clk); > + if (ret) > + return dev_err_probe(priv->dev, ret, "failed to enable clock\n"); > + > + aspeed_peci_property_setup(priv); > + > + aspeed_peci_init_regs(priv); > + > + controller = devm_peci_controller_add(priv->dev, &aspeed_ops); > + if (IS_ERR(controller)) > + return dev_err_probe(priv->dev, PTR_ERR(controller), > + "failed to add aspeed peci controller\n"); > + > + priv->controller = controller; > + > + return 0; > +} > + > +static const struct of_device_id aspeed_peci_of_table[] = { > + { .compatible = "aspeed,ast2400-peci", }, > + { .compatible = "aspeed,ast2500-peci", }, > + { .compatible = "aspeed,ast2600-peci", }, > + { } > +}; > +MODULE_DEVICE_TABLE(of, aspeed_peci_of_table); > + > +static struct platform_driver aspeed_peci_driver = { > + .probe = aspeed_peci_probe, > + .driver = { > + .name = "peci-aspeed", > + .of_match_table = aspeed_peci_of_table, > + }, > +}; > +module_platform_driver(aspeed_peci_driver); > + > +MODULE_AUTHOR("Ryan Chen "); > +MODULE_AUTHOR("Jae Hyun Yoo "); > +MODULE_DESCRIPTION("ASPEED PECI driver"); > +MODULE_LICENSE("GPL"); > +MODULE_IMPORT_NS(PECI); > -- > 2.31.1 >