From patchwork Thu Jan 7 04:37:14 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Moritz Fischer X-Patchwork-Id: 12002851 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=-17.0 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 25B4BC433E6 for ; Thu, 7 Jan 2021 04:39:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EDD5023118 for ; Thu, 7 Jan 2021 04:39:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726414AbhAGEjU (ORCPT ); Wed, 6 Jan 2021 23:39:20 -0500 Received: from mail-pl1-f175.google.com ([209.85.214.175]:37154 "EHLO mail-pl1-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727195AbhAGEjP (ORCPT ); Wed, 6 Jan 2021 23:39:15 -0500 Received: by mail-pl1-f175.google.com with SMTP id be12so2857169plb.4; Wed, 06 Jan 2021 20:38:59 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=7maq3Ym9jcZUCHH3dsZK5J/VALsB4IdVeXJxQTr5Tqw=; b=NHVWL5WtymNU02YBHjRbeHgUc9VB3OUbwo0+F65+cwgsEynedVMz+F37Z243PiG4EY LoG8SBBHY0Luq5zjg7xWv3Tmr0+tp2qC5fyr1HLzWsJK/Xea9bBTxlyIsaov4Gh2WIUA qnXmW+UTvnvmxm38gcA07kvt9MCkEY72x3yIS1xZ1bZqudmW2xgJfUBUKVEexfde6x0t K8AcR5zsbYW0yj8b/glo1fW6f/+PwxIVhSiL/x9iKUuvCCg/qLAZPZuIjpjxkkCmbyiD +X+pLI2O3Tzr+G5k4bKpaYUqYplIUn/YQtWQ2/vhmfdcSgNXtv98coa7FDho9XHQxpuR f94w== X-Gm-Message-State: AOAM532G6kECVNE2gcPB5O0ZYPakLei9vXrX8/yOxTYPOLXgZHC27zWj hFJCyDr7EVmoUtzmSbgsAvI= X-Google-Smtp-Source: ABdhPJwylNfZPZeEfbXEk7OZHctLa1XWvDrTQMydZbQ8g7P36/oJn3Y5pOWsntXuCal5zfZwwxtbxg== X-Received: by 2002:a17:90a:4817:: with SMTP id a23mr7410201pjh.16.1609994314406; Wed, 06 Jan 2021 20:38:34 -0800 (PST) Received: from localhost ([2601:647:5b00:1161:a4cc:eef9:fbc0:2781]) by smtp.gmail.com with ESMTPSA id p187sm4045476pfp.60.2021.01.06.20.38.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 06 Jan 2021 20:38:33 -0800 (PST) From: Moritz Fischer To: gregkh@linuxfoundation.org Cc: linux-fpga@vger.kernel.org, linux-kernel@vger.kernel.org, trix@redhat.com, moritzf@google.com, Moritz Fischer , Xu Yilun , Russ Weight , Krzysztof Kozlowski Subject: [PATCH 8/8] memory: dfl-emif: add the DFL EMIF private feature driver Date: Wed, 6 Jan 2021 20:37:14 -0800 Message-Id: <20210107043714.991646-9-mdf@kernel.org> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210107043714.991646-1-mdf@kernel.org> References: <20210107043714.991646-1-mdf@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fpga@vger.kernel.org From: Xu Yilun This driver is for the EMIF private feature implemented under FPGA Device Feature List (DFL) framework. It is used to expose memory interface status information as well as memory clearing control. The purpose of memory clearing block is to zero out all private memory when FPGA is to be reprogrammed. This gives users a reliable method to prevent potential data leakage. [mdf@kernel.org: Fixed up ABI doc] Signed-off-by: Xu Yilun Signed-off-by: Russ Weight Reviewed-by: Tom Rix Acked-by: Krzysztof Kozlowski --- .../ABI/testing/sysfs-bus-dfl-devices-emif | 25 +++ drivers/memory/Kconfig | 9 + drivers/memory/Makefile | 2 + drivers/memory/dfl-emif.c | 207 ++++++++++++++++++ 4 files changed, 243 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-bus-dfl-devices-emif create mode 100644 drivers/memory/dfl-emif.c diff --git a/Documentation/ABI/testing/sysfs-bus-dfl-devices-emif b/Documentation/ABI/testing/sysfs-bus-dfl-devices-emif new file mode 100644 index 000000000000..817d14126d4d --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-dfl-devices-emif @@ -0,0 +1,25 @@ +What: /sys/bus/dfl/devices/dfl_dev.X/infX_cal_fail +Date: Oct 2020 +KernelVersion: 5.12 +Contact: Xu Yilun +Description: Read-only. It indicates if the calibration failed on this + memory interface. "1" for calibration failure, "0" for OK. + Format: %u + +What: /sys/bus/dfl/devices/dfl_dev.X/infX_init_done +Date: Oct 2020 +KernelVersion: 5.12 +Contact: Xu Yilun +Description: Read-only. It indicates if the initialization completed on + this memory interface. "1" for initialization complete, "0" + for not yet. + Format: %u + +What: /sys/bus/dfl/devices/dfl_dev.X/infX_clear +Date: Oct 2020 +KernelVersion: 5.12 +Contact: Xu Yilun +Description: Write-only. Writing "1" to this file will zero out all memory + data in this memory interface. Writing of other values is + invalid. + Format: %u diff --git a/drivers/memory/Kconfig b/drivers/memory/Kconfig index 3ea6913df176..3c9a9882ef28 100644 --- a/drivers/memory/Kconfig +++ b/drivers/memory/Kconfig @@ -137,6 +137,15 @@ config TI_EMIF_SRAM sequence so this driver provides several relocatable PM functions for the SoC PM code to use. +config FPGA_DFL_EMIF + tristate "FPGA DFL EMIF Driver" + depends on FPGA_DFL && HAS_IOMEM + help + This driver is for the EMIF private feature implemented under + FPGA Device Feature List (DFL) framework. It is used to expose + memory interface status information as well as memory clearing + control. + config MVEBU_DEVBUS bool "Marvell EBU Device Bus Controller" default y if PLAT_ORION diff --git a/drivers/memory/Makefile b/drivers/memory/Makefile index e71cf7b99641..bc7663ed1c25 100644 --- a/drivers/memory/Makefile +++ b/drivers/memory/Makefile @@ -28,6 +28,8 @@ obj-$(CONFIG_STM32_FMC2_EBI) += stm32-fmc2-ebi.o obj-$(CONFIG_SAMSUNG_MC) += samsung/ obj-$(CONFIG_TEGRA_MC) += tegra/ obj-$(CONFIG_TI_EMIF_SRAM) += ti-emif-sram.o +obj-$(CONFIG_FPGA_DFL_EMIF) += dfl-emif.o + ti-emif-sram-objs := ti-emif-pm.o ti-emif-sram-pm.o AFLAGS_ti-emif-sram-pm.o :=-Wa,-march=armv7-a diff --git a/drivers/memory/dfl-emif.c b/drivers/memory/dfl-emif.c new file mode 100644 index 000000000000..3f719816771d --- /dev/null +++ b/drivers/memory/dfl-emif.c @@ -0,0 +1,207 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * DFL device driver for EMIF private feature + * + * Copyright (C) 2020 Intel Corporation, Inc. + * + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define FME_FEATURE_ID_EMIF 0x9 + +#define EMIF_STAT 0x8 +#define EMIF_STAT_INIT_DONE_SFT 0 +#define EMIF_STAT_CALC_FAIL_SFT 8 +#define EMIF_STAT_CLEAR_BUSY_SFT 16 +#define EMIF_CTRL 0x10 +#define EMIF_CTRL_CLEAR_EN_SFT 0 +#define EMIF_CTRL_CLEAR_EN_MSK GENMASK_ULL(3, 0) + +#define EMIF_POLL_INVL 10000 /* us */ +#define EMIF_POLL_TIMEOUT 5000000 /* us */ + +struct dfl_emif { + struct device *dev; + void __iomem *base; + spinlock_t lock; /* Serialises access to EMIF_CTRL reg */ +}; + +struct emif_attr { + struct device_attribute attr; + u32 shift; + u32 index; +}; + +#define to_emif_attr(dev_attr) \ + container_of(dev_attr, struct emif_attr, attr) + +static ssize_t emif_state_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct emif_attr *eattr = to_emif_attr(attr); + struct dfl_emif *de = dev_get_drvdata(dev); + u64 val; + + val = readq(de->base + EMIF_STAT); + + return sysfs_emit(buf, "%u\n", + !!(val & BIT_ULL(eattr->shift + eattr->index))); +} + +static ssize_t emif_clear_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct emif_attr *eattr = to_emif_attr(attr); + struct dfl_emif *de = dev_get_drvdata(dev); + u64 clear_busy_msk, clear_en_msk, val; + void __iomem *base = de->base; + + if (!sysfs_streq(buf, "1")) + return -EINVAL; + + clear_busy_msk = BIT_ULL(EMIF_STAT_CLEAR_BUSY_SFT + eattr->index); + clear_en_msk = BIT_ULL(EMIF_CTRL_CLEAR_EN_SFT + eattr->index); + + spin_lock(&de->lock); + /* The CLEAR_EN field is WO, but other fields are RW */ + val = readq(base + EMIF_CTRL); + val &= ~EMIF_CTRL_CLEAR_EN_MSK; + val |= clear_en_msk; + writeq(val, base + EMIF_CTRL); + spin_unlock(&de->lock); + + if (readq_poll_timeout(base + EMIF_STAT, val, + !(val & clear_busy_msk), + EMIF_POLL_INVL, EMIF_POLL_TIMEOUT)) { + dev_err(de->dev, "timeout, fail to clear\n"); + return -ETIMEDOUT; + } + + return count; +} + +#define emif_state_attr(_name, _shift, _index) \ + static struct emif_attr emif_attr_##inf##_index##_##_name = \ + { .attr = __ATTR(inf##_index##_##_name, 0444, \ + emif_state_show, NULL), \ + .shift = (_shift), .index = (_index) } + +#define emif_clear_attr(_index) \ + static struct emif_attr emif_attr_##inf##_index##_clear = \ + { .attr = __ATTR(inf##_index##_clear, 0200, \ + NULL, emif_clear_store), \ + .index = (_index) } + +emif_state_attr(init_done, EMIF_STAT_INIT_DONE_SFT, 0); +emif_state_attr(init_done, EMIF_STAT_INIT_DONE_SFT, 1); +emif_state_attr(init_done, EMIF_STAT_INIT_DONE_SFT, 2); +emif_state_attr(init_done, EMIF_STAT_INIT_DONE_SFT, 3); + +emif_state_attr(cal_fail, EMIF_STAT_CALC_FAIL_SFT, 0); +emif_state_attr(cal_fail, EMIF_STAT_CALC_FAIL_SFT, 1); +emif_state_attr(cal_fail, EMIF_STAT_CALC_FAIL_SFT, 2); +emif_state_attr(cal_fail, EMIF_STAT_CALC_FAIL_SFT, 3); + +emif_clear_attr(0); +emif_clear_attr(1); +emif_clear_attr(2); +emif_clear_attr(3); + +static struct attribute *dfl_emif_attrs[] = { + &emif_attr_inf0_init_done.attr.attr, + &emif_attr_inf0_cal_fail.attr.attr, + &emif_attr_inf0_clear.attr.attr, + + &emif_attr_inf1_init_done.attr.attr, + &emif_attr_inf1_cal_fail.attr.attr, + &emif_attr_inf1_clear.attr.attr, + + &emif_attr_inf2_init_done.attr.attr, + &emif_attr_inf2_cal_fail.attr.attr, + &emif_attr_inf2_clear.attr.attr, + + &emif_attr_inf3_init_done.attr.attr, + &emif_attr_inf3_cal_fail.attr.attr, + &emif_attr_inf3_clear.attr.attr, + + NULL, +}; + +static umode_t dfl_emif_visible(struct kobject *kobj, + struct attribute *attr, int n) +{ + struct dfl_emif *de = dev_get_drvdata(kobj_to_dev(kobj)); + struct emif_attr *eattr = container_of(attr, struct emif_attr, + attr.attr); + u64 val; + + /* + * This device supports upto 4 memory interfaces, but not all + * interfaces are used on different platforms. The read out value of + * CLEAN_EN field (which is a bitmap) could tell how many interfaces + * are available. + */ + val = FIELD_GET(EMIF_CTRL_CLEAR_EN_MSK, readq(de->base + EMIF_CTRL)); + + return (val & BIT_ULL(eattr->index)) ? attr->mode : 0; +} + +static const struct attribute_group dfl_emif_group = { + .is_visible = dfl_emif_visible, + .attrs = dfl_emif_attrs, +}; + +static const struct attribute_group *dfl_emif_groups[] = { + &dfl_emif_group, + NULL, +}; + +static int dfl_emif_probe(struct dfl_device *ddev) +{ + struct device *dev = &ddev->dev; + struct dfl_emif *de; + + de = devm_kzalloc(dev, sizeof(*de), GFP_KERNEL); + if (!de) + return -ENOMEM; + + de->base = devm_ioremap_resource(dev, &ddev->mmio_res); + if (IS_ERR(de->base)) + return PTR_ERR(de->base); + + de->dev = dev; + spin_lock_init(&de->lock); + dev_set_drvdata(dev, de); + + return 0; +} + +static const struct dfl_device_id dfl_emif_ids[] = { + { FME_ID, FME_FEATURE_ID_EMIF }, + { } +}; +MODULE_DEVICE_TABLE(dfl, dfl_emif_ids); + +static struct dfl_driver dfl_emif_driver = { + .drv = { + .name = "dfl-emif", + .dev_groups = dfl_emif_groups, + }, + .id_table = dfl_emif_ids, + .probe = dfl_emif_probe, +}; +module_dfl_driver(dfl_emif_driver); + +MODULE_DESCRIPTION("DFL EMIF driver"); +MODULE_AUTHOR("Intel Corporation"); +MODULE_LICENSE("GPL v2");