| Message ID | 1602313793-21421-7-git-send-email-yilun.xu@intel.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
| Series | add DFL bus support to MODULE_DEVICE_TABLE() | expand |
On Sat, 10 Oct 2020 at 09:15, Xu Yilun <yilun.xu@intel.com> wrote: > > 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 <yilun.xu@intel.com> > Signed-off-by: Russ Weight <russell.h.weight@intel.com> > Acked-by: Krzysztof Kozlowski <krzk@kernel.org> > --- > 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. > v9: Add static prefix for emif attributes macro > Update the kernel version of the sysfs interfaces in Doc. > --- > .../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 > I am confused now. This was already taken by Moritz, wasn't it? And the dependencies were already taken, weren't they? Previously it was depending on "Modularization of DFL private feature drivers" and "add dfl bus support to MODULE_DEVICE_TABLE()"... now this is here so did the dependencies change? What is the reason to include this patch here? My ack was for the purpose of taking it via Moritz tree, because of the dependencies. If this is not the case, then probably better to take it via memory controllers tree to avoid any conflicts (it's not a small change). Best regards, Krzysztof
Hi Krzysztof, On Mon, Oct 12, 2020 at 06:40:46PM +0200, Krzysztof Kozlowski wrote: > On Sat, 10 Oct 2020 at 09:15, Xu Yilun <yilun.xu@intel.com> wrote: > > > > 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 <yilun.xu@intel.com> > > Signed-off-by: Russ Weight <russell.h.weight@intel.com> > > Acked-by: Krzysztof Kozlowski <krzk@kernel.org> > > --- > > 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. > > v9: Add static prefix for emif attributes macro > > Update the kernel version of the sysfs interfaces in Doc. > > --- > > .../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 > > > > I am confused now. This was already taken by Moritz, wasn't it? And > the dependencies were already taken, weren't they? Previously it was > depending on "Modularization of DFL private feature drivers" and "add > dfl bus support to MODULE_DEVICE_TABLE()"... now this is here so did > the dependencies change? What is the reason to include this patch > here? It is confusing. Basically Greg had comments on the patch after I had applied it. It's going through anothe round of review. > > My ack was for the purpose of taking it via Moritz tree, because of > the dependencies. If this is not the case, then probably better to > take it via memory controllers tree to avoid any conflicts (it's not a > small change). Once it's ok I can put it on a branch with a stable tag and you can pull that in and take the patch through your tree. Does that work? Sorry for the mess, Moritz
On Mon, Oct 12, 2020 at 09:58:03AM -0700, Moritz Fischer wrote: > Hi Krzysztof, > > On Mon, Oct 12, 2020 at 06:40:46PM +0200, Krzysztof Kozlowski wrote: > > On Sat, 10 Oct 2020 at 09:15, Xu Yilun <yilun.xu@intel.com> wrote: > > > > > > 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 <yilun.xu@intel.com> > > > Signed-off-by: Russ Weight <russell.h.weight@intel.com> > > > Acked-by: Krzysztof Kozlowski <krzk@kernel.org> > > > --- > > > 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. > > > v9: Add static prefix for emif attributes macro > > > Update the kernel version of the sysfs interfaces in Doc. > > > --- > > > .../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 > > > > > > > I am confused now. This was already taken by Moritz, wasn't it? And > > the dependencies were already taken, weren't they? Previously it was > > depending on "Modularization of DFL private feature drivers" and "add > > dfl bus support to MODULE_DEVICE_TABLE()"... now this is here so did > > the dependencies change? What is the reason to include this patch > > here? > > It is confusing. Basically Greg had comments on the patch after I had > applied it. It's going through anothe round of review. > > > > > My ack was for the purpose of taking it via Moritz tree, because of > > the dependencies. If this is not the case, then probably better to > > take it via memory controllers tree to avoid any conflicts (it's not a > > small change). > > Once it's ok I can put it on a branch with a stable tag and you can pull > that in and take the patch through your tree. I am not going to apply any new patches before end of merge window, so if you can still push it to Greg for v5.10, then please take it. However I think Greg also does not take patches during merge window, so most likely this will wait for the next cycle. In such case let's do it via stable tag for DFL parts. Best regards, Krzysztof
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..1ae8ebd --- /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: 5.11 +Contact: Xu Yilun <yilun.xu@intel.com> +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: 5.11 +Contact: Xu Yilun <yilun.xu@intel.com> +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: 5.11 +Contact: Xu Yilun <yilun.xu@intel.com> +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..dcbc741e --- /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 <linux/bitfield.h> +#include <linux/errno.h> +#include <linux/fpga/dfl.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/io-64-nonatomic-lo-hi.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/spinlock.h> +#include <linux/types.h> + +#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) \ + 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");