Re: [PATCH 1/1] fpga: intel-m10-bmc-log: Create MAX 10 BMC log driver

[Xu Yilun]

On 2023-02-09 at 13:13:28 +0200, Ilpo Järvinen wrote:
> Add MAX 10 BMC log driver for accessing BMC event log, FPGA image
> directory, and bill-of-materials (BOM) info partitions on FPGA card's
> flash. Use the nvmem API to expose the event MAX 10 BMC event logs to
> userspace.

I didn't look into the details yet, but I suppose this driver is not
for FPGA domain, which focuses on FPGA region re-configuration and
re-enumeration of devices in FPGA region.

Thanks,
Yilun

> 
> The PMCI MAX 10 BMC contains high and low timestamp registers that are
> periodically written by the host driver to facilitate BMC event logs.
> Add a kernel worker thread to update the BMC timestamp registers. The
> frequency of timestamp updates is controlled through sysfs file (the
> default frequency is once per minute).
> 
> Co-developed-by: Russ Weight <russell.h.weight@xxxxxxxxx>
> Signed-off-by: Russ Weight <russell.h.weight@xxxxxxxxx>
> Co-developed-by: Tianfei Zhang <tianfei.zhang@xxxxxxxxx>
> Signed-off-by: Tianfei Zhang <tianfei.zhang@xxxxxxxxx>
> Co-developed-by: Matthew Gerlach <matthew.gerlach@xxxxxxxxxxxxxxx>
> Signed-off-by: Matthew Gerlach <matthew.gerlach@xxxxxxxxxxxxxxx>
> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
> ---
> 
> This requires commit 4f43a6e80ba9 ("fpga: m10bmc-sec: Add support for
> N6000") from ib-mfd-fpga-hwmon-6.3-1 (the 11th patch of the M10 BMC split
> series that wasn't picked up at first and still isn't in for-fpga-v6.3-rc1).
> 
>  .../testing/sysfs-driver-intel-m10-bmc-log    |  37 +++
>  MAINTAINERS                                   |   4 +-
>  drivers/fpga/Kconfig                          |   9 +
>  drivers/fpga/Makefile                         |   3 +-
>  drivers/fpga/intel-m10-bmc-log.c              | 264 ++++++++++++++++++
>  drivers/mfd/intel-m10-bmc-pmci.c              |   1 +
>  include/linux/mfd/intel-m10-bmc.h             |  13 +
>  7 files changed, 329 insertions(+), 2 deletions(-)
>  create mode 100644 Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-log
>  create mode 100644 drivers/fpga/intel-m10-bmc-log.c
> 
> diff --git a/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-log b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-log
> new file mode 100644
> index 000000000000..a170e675d11e
> --- /dev/null
> +++ b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-log
> @@ -0,0 +1,37 @@
> +What: /sys/bus/platform/devices/intel-m10-bmc-log.*.auto/time_sync_frequency
> +Date:		Apr 2023
> +KernelVersion:	6.3
> +Contact:	Russ Weight <russell.h.weight@xxxxxxxxx>
> +Description:	Read/write. This sysfs node controls the frequency (in
> +		seconds) that the host writes to the MAX10 BMC registers
> +		to synchronize the timestamp registers used for the BMC
> +		event log. Write zero to stop the timestamp synchronization.
> +		Write a non-zero integer value to restart or modify the
> +		update frequency. Reading from this file will return the
> +		same integer value.
> +		Format: %u
> +
> +What:		/sys/bus/platform/devices/intel-m10-bmc-log.*.auto/bmc_event_log*/nvmem
> +Date:		Apr 2023
> +KernelVersion:	6.3
> +Contact:	Tianfei zhang <tianfei.zhang@xxxxxxxxx>
> +Description:	Read-only. This file returns the contents of the "evemt log"
> +		partition in flash. This partition includes the event and
> +		error info for the BMC.
> +
> +What:		/sys/bus/platform/devices/intel-m10-bmc-log.*.auto/fpga_image_directory*/nvmem
> +Date:		Apr 2023
> +KernelVersion:	6.3
> +Contact:	Tianfei zhang <tianfei.zhang@xxxxxxxxx>
> +Description:	Read-only. This file returns the contents of the "FPGA image
> +		directory" partition in flash. This partition includes
> +		information like the FPGA Image versions and state.
> +
> +What:		/sys/bus/platform/devices/intel-m10-bmc-log.*.auto/bom_info*/nvmem
> +Date:		Apr 2023
> +KernelVersion:	6.3
> +Contact:	Tianfei zhang <tianfei.zhang@xxxxxxxxx>
> +Description:	Read-only. This file returns the contents of the "BOM info"
> +		partition in flash. This partition includes information such
> +		as the bill of materials (BOM) critical components like
> +		PBA#, MMID.
> diff --git a/MAINTAINERS b/MAINTAINERS
> index ddfa4f8b3c80..1b2427ba6729 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -8075,11 +8075,13 @@ F:	Documentation/fpga/
>  F:	drivers/fpga/
>  F:	include/linux/fpga/
>  
> -INTEL MAX10 BMC SECURE UPDATES
> +INTEL MAX10 BMC SUBDRIVERS
>  M:	Russ Weight <russell.h.weight@xxxxxxxxx>
>  L:	linux-fpga@xxxxxxxxxxxxxxx
>  S:	Maintained
> +F:	Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-log
>  F:	Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-sec-update
> +F:	drivers/fpga/intel-m10-bmc-log.c
>  F:	drivers/fpga/intel-m10-bmc-sec-update.c
>  
>  MICROCHIP POLARFIRE FPGA DRIVERS
> diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
> index 0a00763b9f28..773667e3b027 100644
> --- a/drivers/fpga/Kconfig
> +++ b/drivers/fpga/Kconfig
> @@ -244,6 +244,15 @@ config FPGA_MGR_VERSAL_FPGA
>  
>  	  To compile this as a module, choose M here.
>  
> +config FPGA_M10_BMC_LOG
> +	tristate "Intel MAX 10 Board Management Controller Log Driver"
> +	depends on MFD_INTEL_M10_BMC_CORE
> +	help
> +	  Support for the Intel MAX 10 Board Management Controller (BMC)
> +	  event log, event log timestamp synchronization, and other
> +	  information on flash partitions (available images and
> +	  bill-of-materials critical information).
> +
>  config FPGA_M10_BMC_SEC_UPDATE
>  	tristate "Intel MAX10 BMC Secure Update driver"
>  	depends on MFD_INTEL_M10_BMC_CORE
> diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
> index 72e554b4d2f7..1db25ad3d76a 100644
> --- a/drivers/fpga/Makefile
> +++ b/drivers/fpga/Makefile
> @@ -25,7 +25,8 @@ obj-$(CONFIG_FPGA_MGR_LATTICE_SYSCONFIG_SPI)	+= lattice-sysconfig-spi.o
>  obj-$(CONFIG_ALTERA_PR_IP_CORE)		+= altera-pr-ip-core.o
>  obj-$(CONFIG_ALTERA_PR_IP_CORE_PLAT)	+= altera-pr-ip-core-plat.o
>  
> -# FPGA Secure Update Drivers
> +# MAX10 subdrivers
> +obj-$(CONFIG_FPGA_M10_BMC_LOG)		+= intel-m10-bmc-log.o
>  obj-$(CONFIG_FPGA_M10_BMC_SEC_UPDATE)	+= intel-m10-bmc-sec-update.o
>  
>  # FPGA Bridge Drivers
> diff --git a/drivers/fpga/intel-m10-bmc-log.c b/drivers/fpga/intel-m10-bmc-log.c
> new file mode 100644
> index 000000000000..4e7a54afe786
> --- /dev/null
> +++ b/drivers/fpga/intel-m10-bmc-log.c
> @@ -0,0 +1,264 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Intel Max10 Board Management Controller Log Driver
> + *
> + * Copyright (C) 2021-2023 Intel Corporation.
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/dev_printk.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/nvmem-provider.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/types.h>
> +
> +#include <linux/mfd/intel-m10-bmc.h>
> +
> +#define M10BMC_TIMESTAMP_FREQ			60	/* 60 secs between updates */
> +
> +struct m10bmc_log_cfg {
> +	int el_size;
> +	unsigned long el_off;
> +
> +	int id_size;
> +	unsigned long id_off;
> +
> +	int bi_size;
> +	unsigned long bi_off;
> +};
> +
> +struct m10bmc_log {
> +	struct device *dev;
> +	struct intel_m10bmc *m10bmc;
> +	unsigned int freq_s;		/* update frequency in seconds */
> +	struct delayed_work dwork;
> +	const struct m10bmc_log_cfg *log_cfg;
> +	struct nvmem_device *bmc_event_log_nvmem;
> +	struct nvmem_device *fpga_image_dir_nvmem;
> +	struct nvmem_device *bom_info_nvmem;
> +};
> +
> +static void m10bmc_log_time_sync(struct work_struct *work)
> +{
> +	struct delayed_work *dwork = to_delayed_work(work);
> +	const struct m10bmc_csr_map *csr_map;
> +	struct m10bmc_log *log;
> +	s64 time_ms;
> +	int ret;
> +
> +	log = container_of(dwork, struct m10bmc_log, dwork);
> +	csr_map = log->m10bmc->info->csr_map;
> +
> +	time_ms = ktime_to_ms(ktime_get_real());
> +	ret = regmap_write(log->m10bmc->regmap, csr_map->base + M10BMC_N6000_TIME_HIGH,
> +			   upper_32_bits(time_ms));
> +	if (!ret) {
> +		ret = regmap_write(log->m10bmc->regmap, csr_map->base + M10BMC_N6000_TIME_LOW,
> +				   lower_32_bits(time_ms));
> +	}
> +	if (ret)
> +		dev_err_once(log->dev, "Failed to update BMC timestamp: %d\n", ret);
> +
> +	schedule_delayed_work(&log->dwork, log->freq_s * HZ);
> +}
> +
> +static ssize_t time_sync_frequency_store(struct device *dev, struct device_attribute *attr,
> +					 const char *buf, size_t count)
> +{
> +	struct m10bmc_log *ddata = dev_get_drvdata(dev);
> +	unsigned int old_freq = ddata->freq_s;
> +	int ret;
> +
> +	ret = kstrtouint(buf, 0, &ddata->freq_s);
> +	if (ret)
> +		return ret;
> +
> +	if (old_freq)
> +		cancel_delayed_work_sync(&ddata->dwork);
> +
> +	if (ddata->freq_s)
> +		m10bmc_log_time_sync(&ddata->dwork.work);
> +
> +	return count;
> +}
> +
> +static ssize_t time_sync_frequency_show(struct device *dev, struct device_attribute *attr,
> +					char *buf)
> +{
> +	struct m10bmc_log *ddata = dev_get_drvdata(dev);
> +
> +	return sysfs_emit(buf, "%u\n", ddata->freq_s);
> +}
> +static DEVICE_ATTR_RW(time_sync_frequency);
> +
> +static struct attribute *m10bmc_log_attrs[] = {
> +	&dev_attr_time_sync_frequency.attr,
> +	NULL,
> +};
> +ATTRIBUTE_GROUPS(m10bmc_log);
> +
> +static int bmc_nvmem_read(struct m10bmc_log *ddata, unsigned int addr,
> +			  unsigned int off, void *val, size_t count)
> +{
> +	struct intel_m10bmc *m10bmc = ddata->m10bmc;
> +	int ret;
> +
> +	ret = m10bmc->flash_bulk_ops->read(m10bmc, val, addr + off, count);
> +	if (ret) {
> +		if (ret != -EBUSY)
> +			dev_err(ddata->dev, "failed to read flash %x (%d)\n", addr, ret);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int bmc_event_log_nvmem_read(void *priv, unsigned int off, void *val, size_t count)
> +{
> +	struct m10bmc_log *ddata = priv;
> +
> +	return bmc_nvmem_read(ddata, ddata->log_cfg->el_off, off, val, count);
> +}
> +
> +static int fpga_image_dir_nvmem_read(void *priv, unsigned int off, void *val, size_t count)
> +{
> +	struct m10bmc_log *ddata = priv;
> +
> +	return bmc_nvmem_read(ddata, ddata->log_cfg->id_off, off, val, count);
> +}
> +
> +static int bom_info_nvmem_read(void *priv, unsigned int off, void *val, size_t count)
> +{
> +	struct m10bmc_log *ddata = priv;
> +
> +	return bmc_nvmem_read(ddata, ddata->log_cfg->bi_off, off, val, count);
> +}
> +
> +static struct nvmem_config bmc_event_log_nvmem_config = {
> +	.name = "bmc_event_log",
> +	.stride = 4,
> +	.word_size = 1,
> +	.reg_read = bmc_event_log_nvmem_read,
> +	.id = NVMEM_DEVID_AUTO,
> +};
> +
> +static struct nvmem_config fpga_image_dir_nvmem_config = {
> +	.name = "fpga_image_directory",
> +	.stride = 4,
> +	.word_size = 1,
> +	.reg_read = fpga_image_dir_nvmem_read,
> +	.id = NVMEM_DEVID_AUTO,
> +};
> +
> +static struct nvmem_config bom_info_nvmem_config = {
> +	.name = "bom_info",
> +	.stride = 4,
> +	.word_size = 1,
> +	.reg_read = bom_info_nvmem_read,
> +	.id = NVMEM_DEVID_AUTO,
> +};
> +
> +static int m10bmc_log_probe(struct platform_device *pdev)
> +{
> +	const struct platform_device_id *id = platform_get_device_id(pdev);
> +	struct intel_m10bmc *m10bmc = dev_get_drvdata(pdev->dev.parent);
> +	struct nvmem_config nvconfig;
> +	struct m10bmc_log *ddata;
> +
> +	if (WARN_ON_ONCE(!m10bmc->flash_bulk_ops))
> +		return -ENODEV;
> +
> +	ddata = devm_kzalloc(&pdev->dev, sizeof(*ddata), GFP_KERNEL);
> +	if (!ddata)
> +		return -ENOMEM;
> +
> +	ddata->dev = &pdev->dev;
> +	ddata->m10bmc = m10bmc;
> +	ddata->freq_s = M10BMC_TIMESTAMP_FREQ;
> +	INIT_DELAYED_WORK(&ddata->dwork, m10bmc_log_time_sync);
> +	ddata->log_cfg = (struct m10bmc_log_cfg *)id->driver_data;
> +	dev_set_drvdata(&pdev->dev, ddata);
> +
> +	if (ddata->log_cfg->el_size > 0) {
> +		m10bmc_log_time_sync(&ddata->dwork.work);
> +
> +		memcpy(&nvconfig, &bmc_event_log_nvmem_config, sizeof(bmc_event_log_nvmem_config));
> +		nvconfig.dev = ddata->dev;
> +		nvconfig.priv = ddata;
> +		nvconfig.size = ddata->log_cfg->el_size;
> +
> +		ddata->bmc_event_log_nvmem = devm_nvmem_register(ddata->dev, &nvconfig);
> +		if (IS_ERR(ddata->bmc_event_log_nvmem))
> +			return PTR_ERR(ddata->bmc_event_log_nvmem);
> +	}
> +
> +	if (ddata->log_cfg->id_size > 0) {
> +		memcpy(&nvconfig, &fpga_image_dir_nvmem_config, sizeof(fpga_image_dir_nvmem_config));
> +		nvconfig.dev = ddata->dev;
> +		nvconfig.priv = ddata;
> +		nvconfig.size = ddata->log_cfg->id_size;
> +
> +		ddata->fpga_image_dir_nvmem = devm_nvmem_register(ddata->dev, &nvconfig);
> +		if (IS_ERR(ddata->fpga_image_dir_nvmem))
> +			return PTR_ERR(ddata->fpga_image_dir_nvmem);
> +	}
> +
> +	if (ddata->log_cfg->bi_size > 0) {
> +		memcpy(&nvconfig, &bom_info_nvmem_config, sizeof(bom_info_nvmem_config));
> +		nvconfig.dev = ddata->dev;
> +		nvconfig.priv = ddata;
> +		nvconfig.size = ddata->log_cfg->bi_size;
> +
> +		ddata->bom_info_nvmem = devm_nvmem_register(ddata->dev, &nvconfig);
> +		if (IS_ERR(ddata->bom_info_nvmem))
> +			return PTR_ERR(ddata->bom_info_nvmem);
> +	}
> +
> +	return 0;
> +}
> +
> +static int m10bmc_log_remove(struct platform_device *pdev)
> +{
> +	struct m10bmc_log *ddata = dev_get_drvdata(&pdev->dev);
> +
> +	cancel_delayed_work_sync(&ddata->dwork);
> +
> +	return 0;
> +}
> +
> +static const struct m10bmc_log_cfg m10bmc_log_n6000_cfg = {
> +	.el_size = M10BMC_N6000_ERROR_LOG_SIZE,
> +	.el_off = M10BMC_N6000_ERROR_LOG_ADDR,
> +
> +	.id_size = M10BMC_N6000_FPGA_IMAGE_DIR_SIZE,
> +	.id_off = M10BMC_N6000_FPGA_IMAGE_DIR_ADDR,
> +
> +	.bi_size = M10BMC_N6000_BOM_INFO_SIZE,
> +	.bi_off = M10BMC_N6000_BOM_INFO_ADDR,
> +};
> +
> +static const struct platform_device_id intel_m10bmc_log_ids[] = {
> +	{
> +		.name = "n6000bmc-log",
> +		.driver_data = (unsigned long)&m10bmc_log_n6000_cfg,
> +	},
> +	{ }
> +};
> +
> +static struct platform_driver intel_m10bmc_log_driver = {
> +	.probe = m10bmc_log_probe,
> +	.remove = m10bmc_log_remove,
> +	.driver = {
> +		.name = "intel-m10-bmc-log",
> +		.dev_groups = m10bmc_log_groups,
> +	},
> +	.id_table = intel_m10bmc_log_ids,
> +};
> +module_platform_driver(intel_m10bmc_log_driver);
> +
> +MODULE_DEVICE_TABLE(platform, intel_m10bmc_log_ids);
> +MODULE_AUTHOR("Intel Corporation");
> +MODULE_DESCRIPTION("Intel MAX 10 BMC log driver");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/mfd/intel-m10-bmc-pmci.c b/drivers/mfd/intel-m10-bmc-pmci.c
> index 8821f1876dd6..f8803b7bb98e 100644
> --- a/drivers/mfd/intel-m10-bmc-pmci.c
> +++ b/drivers/mfd/intel-m10-bmc-pmci.c
> @@ -350,6 +350,7 @@ static struct regmap_config m10bmc_pmci_regmap_config = {
>  static struct mfd_cell m10bmc_pmci_n6000_bmc_subdevs[] = {
>  	{ .name = "n6000bmc-hwmon" },
>  	{ .name = "n6000bmc-sec-update" },
> +	{ .name = "n6000bmc-log" },
>  };
>  
>  static const struct m10bmc_csr_map m10bmc_n6000_csr_map = {
> diff --git a/include/linux/mfd/intel-m10-bmc.h b/include/linux/mfd/intel-m10-bmc.h
> index 1812ebfa11a8..1079e580e9e6 100644
> --- a/include/linux/mfd/intel-m10-bmc.h
> +++ b/include/linux/mfd/intel-m10-bmc.h
> @@ -125,6 +125,9 @@
>  #define M10BMC_N6000_SYS_BASE			0x0
>  #define M10BMC_N6000_SYS_END			0xfff
>  
> +#define M10BMC_N6000_TIME_LOW			0x178
> +#define M10BMC_N6000_TIME_HIGH			0x17c
> +
>  #define M10BMC_N6000_DOORBELL			0x1c0
>  #define M10BMC_N6000_AUTH_RESULT		0x1c4
>  #define AUTH_RESULT_RSU_STATUS			GENMASK(23, 16)
> @@ -134,6 +137,16 @@
>  #define M10BMC_N6000_MAC_LOW			0x20
>  #define M10BMC_N6000_MAC_HIGH			(M10BMC_N6000_MAC_LOW + 4)
>  
> +/* Addresses for BMC log data in FLASH */
> +#define M10BMC_N6000_ERROR_LOG_ADDR		0x7fb0000
> +#define M10BMC_N6000_ERROR_LOG_SIZE		0x40000
> +
> +#define M10BMC_N6000_FPGA_IMAGE_DIR_ADDR	0x7ff6000
> +#define M10BMC_N6000_FPGA_IMAGE_DIR_SIZE	0x3000
> +
> +#define M10BMC_N6000_BOM_INFO_ADDR		0x7ff0000
> +#define M10BMC_N6000_BOM_INFO_SIZE		0x2000
> +
>  /* Addresses for security related data in FLASH */
>  #define M10BMC_N6000_BMC_REH_ADDR		0x7ffc004
>  #define M10BMC_N6000_BMC_PROG_ADDR		0x7ffc000
> -- 
> 2.30.2
>