From patchwork Mon Sep 21 05:31:20 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xu Yilun X-Patchwork-Id: 11788321 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 408CD139F for ; Mon, 21 Sep 2020 05:36:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2CB19207D3 for ; Mon, 21 Sep 2020 05:36:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726357AbgIUFgA (ORCPT ); Mon, 21 Sep 2020 01:36:00 -0400 Received: from mga18.intel.com ([134.134.136.126]:9101 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726104AbgIUFgA (ORCPT ); Mon, 21 Sep 2020 01:36:00 -0400 IronPort-SDR: gbyYo6daRhzVjsz8V0vV2L9qXuZEwmw4IUJJ/3So40Meb5qq/cu2SbpJ88/IJb9QOaqUWFroCm jKDD/YuJpRqg== X-IronPort-AV: E=McAfee;i="6000,8403,9750"; a="148064998" X-IronPort-AV: E=Sophos;i="5.77,285,1596524400"; d="scan'208";a="148064998" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Sep 2020 22:35:59 -0700 IronPort-SDR: LcUWuf5r39ZomwHn+/GSlbkk/FCTJOnx3d2DCgZ36A1M9o4mSqAyIa5y4pJ9U//Hw2i+c13BsV yoQyxSSQPuTA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.77,285,1596524400"; d="scan'208";a="334240019" Received: from yilunxu-optiplex-7050.sh.intel.com ([10.239.159.141]) by fmsmga004.fm.intel.com with ESMTP; 20 Sep 2020 22:35:57 -0700 From: Xu Yilun To: krzk@kernel.org, mdf@kernel.org, linux-fpga@vger.kernel.org, linux-kernel@vger.kernel.org Cc: trix@redhat.com, yilun.xu@intel.com, lgoncalv@redhat.com, Russ Weight Subject: [PATCH v3] memory: dfl-emif: add the DFL EMIF private feature driver Date: Mon, 21 Sep 2020 13:31:20 +0800 Message-Id: <1600666280-25651-2-git-send-email-yilun.xu@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1600666280-25651-1-git-send-email-yilun.xu@intel.com> References: <1600666280-25651-1-git-send-email-yilun.xu@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-fpga@vger.kernel.org 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. Signed-off-by: Xu Yilun Signed-off-by: Russ Weight Acked-by: Krzysztof Kozlowski --- v2: Adjust the position of this driver in Kconfig. Improves the name of the Kconfig option. Change the include dfl-bus.h to dfl.h, cause the previous patchset renames the file. Some minor fixes and comment improvement. v3: Adjust the position of the driver in Makefile. --- .../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 0000000..56f97dc --- /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: Sep 2020 +KernelVersion: 5.10 +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: Sep 2020 +KernelVersion: 5.10 +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: Sep 2020 +KernelVersion: 5.10 +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 00e013b..2495bc4 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 e71cf7b..bc7663e 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 0000000..0799d53 --- /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 sprintf(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) \ + 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) \ + 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 *dfl_dev) +{ + struct device *dev = &dfl_dev->dev; + struct dfl_emif *de; + + de = devm_kzalloc(dev, sizeof(*de), GFP_KERNEL); + if (!de) + return -ENOMEM; + + de->base = devm_ioremap_resource(dev, &dfl_dev->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");