On 10/2/20 6:24 PM, Russ Weight wrote:
> Create a platform driver that can be invoked as a sub
> driver for the Intel MAX10 BMC in order to support
> secure updates. This sub-driver will invoke an
> instance of the Intel FPGA Security Manager class driver
> in order to expose sysfs interfaces for managing and
> monitoring secure updates to FPGA and BMC images.
>
> This patch creates the MAX10 BMC Security Engine driver and
> provides support for displaying the current root entry hashes
> for the FPGA static region, the FPGA PR region, and the MAX10
> BMC.
>
> Signed-off-by: Russ Weight <russell.h.weight@xxxxxxxxx>
> ---
> v2:
> - Added drivers/fpga/intel-m10-bmc-secure.c file to MAINTAINERS.
> - Switched to GENMASK(31, 16) for a couple of mask definitions.
> - Moved MAX10 BMC address and function definitions to a separate
> patch.
> - Replaced small function-creation macros with explicit function
> declarations.
> - Removed ifpga_sec_mgr_init() and ifpga_sec_mgr_uinit() functions.
> - Adapted to changes in the Intel FPGA Security Manager by splitting
> the single call to ifpga_sec_mgr_register() into two function
> calls: devm_ifpga_sec_mgr_create() and ifpga_sec_mgr_register().
> ---
> MAINTAINERS | 1 +
> drivers/fpga/Kconfig | 11 ++
> drivers/fpga/Makefile | 3 +
> drivers/fpga/intel-m10-bmc-secure.c | 165 ++++++++++++++++++++++++++++
> 4 files changed, 180 insertions(+)
> create mode 100644 drivers/fpga/intel-m10-bmc-secure.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 0bb5ef309dec..c359d0214980 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -6898,6 +6898,7 @@ S: Maintained
> F: Documentation/ABI/testing/sysfs-class-ifpga-sec-mgr
> F: Documentation/fpga/ifpga-sec-mgr.rst
> F: drivers/fpga/ifpga-sec-mgr.c
> +F: drivers/fpga/intel-m10-bmc-secure.c
> F: include/linux/fpga/ifpga-sec-mgr.h
>
> FPU EMULATOR
> diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
> index c534cc80f398..2380d36b08c7 100644
> --- a/drivers/fpga/Kconfig
> +++ b/drivers/fpga/Kconfig
> @@ -235,4 +235,15 @@ config IFPGA_SEC_MGR
> region and for the BMC. Select this option to enable
> updates for secure FPGA devices.
>
> +config IFPGA_M10_BMC_SECURE
> + tristate "Intel MAX10 BMC security engine"
> + depends on MFD_INTEL_M10_BMC && IFPGA_SEC_MGR
> + help
> + Secure update support for the Intel MAX10 board management
> + controller.
> +
> + This is a subdriver of the Intel MAX10 board management controller
> + (BMC) and provides support for secure updates for the BMC image,
> + the FPGA image, the Root Entry Hashes, etc.
> +
> endif # FPGA
> diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
> index 6f706590e209..8e702689cdda 100644
> --- a/drivers/fpga/Makefile
> +++ b/drivers/fpga/Makefile
> @@ -24,6 +24,9 @@ obj-$(CONFIG_ALTERA_PR_IP_CORE_PLAT) += altera-pr-ip-core-plat.o
> # Intel FPGA Security Manager Framework
> obj-$(CONFIG_IFPGA_SEC_MGR) += ifpga-sec-mgr.o
>
> +# Intel Security Manager Drivers
> +obj-$(CONFIG_IFPGA_M10_BMC_SECURE) += intel-m10-bmc-secure.o
> +
> # FPGA Bridge Drivers
> obj-$(CONFIG_FPGA_BRIDGE) += fpga-bridge.o
> obj-$(CONFIG_SOCFPGA_FPGA_BRIDGE) += altera-hps2fpga.o altera-fpga2sdram.o
> diff --git a/drivers/fpga/intel-m10-bmc-secure.c b/drivers/fpga/intel-m10-bmc-secure.c
> new file mode 100644
> index 000000000000..df8ebda9a9cb
> --- /dev/null
> +++ b/drivers/fpga/intel-m10-bmc-secure.c
> @@ -0,0 +1,165 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Intel Max10 Board Management Controller Security Engine Driver
> + *
> + * Copyright (C) 2019-2020 Intel Corporation. All rights reserved.
> + *
> + */
> +#include <linux/bitfield.h>
> +#include <linux/device.h>
> +#include <linux/fpga/ifpga-sec-mgr.h>
> +#include <linux/mfd/intel-m10-bmc.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/vmalloc.h>
> +
> +struct m10bmc_sec {
> + struct device *dev;
> + struct intel_m10bmc *m10bmc;
> + struct ifpga_sec_mgr *imgr;
> +};
> +
> +#define REH_SHA256_SIZE 32
> +#define REH_SHA384_SIZE 48
> +#define REH_MAGIC GENMASK(15, 0)
> +#define REH_SHA_NUM_BYTES GENMASK(31, 16)
> +
> +static int m10bmc_reh_size(struct ifpga_sec_mgr *imgr,
> + u32 exp_magic, u32 prog_addr)
> +{
> + struct m10bmc_sec *sec = imgr->priv;
> + int sha_num_bytes, ret;
> + u32 magic;
> +
> + ret = m10bmc_raw_read(sec->m10bmc, prog_addr, &magic);
> + if (ret)
> + return ret;
> +
> + dev_dbg(sec->dev, "%s magic 0x%08x\n", __func__, magic);
> +
> + /*
> + * If no magic number, then no REH is programmed, so
> + * the REH size is zero.
> + */
> + if (FIELD_GET(REH_MAGIC, magic) != exp_magic)
> + return 0;
> +
> + sha_num_bytes = FIELD_GET(REH_SHA_NUM_BYTES, magic) / 8;
> + if (sha_num_bytes != REH_SHA256_SIZE &&
> + sha_num_bytes != REH_SHA384_SIZE) {
> + dev_err(sec->dev, "%s bad sha num bytes %d\n", __func__,
> + sha_num_bytes);
> + return -EINVAL;
> + }
> +
> + return sha_num_bytes;
> +}
> +
> +static int m10bmc_bmc_reh_size(struct ifpga_sec_mgr *imgr)
For naming consistency, the _reh_ vs _root_entry_hash_
pick one.
If you pick _reh_ put a comment at the top since reh isn't a familiar acronym (at least to me)
> +{
> + return m10bmc_reh_size(imgr, BMC_PROG_MAGIC, BMC_PROG_ADDR);
> +}
> +
> +static int m10bmc_sr_reh_size(struct ifpga_sec_mgr *imgr)
> +{
> + return m10bmc_reh_size(imgr, SR_PROG_MAGIC, SR_PROG_ADDR);
> +}
> +
> +static int m10bmc_pr_reh_size(struct ifpga_sec_mgr *imgr)
> +{
> + return m10bmc_reh_size(imgr, PR_PROG_MAGIC, PR_PROG_ADDR);
> +}
> +
> +static int m10bmc_root_entry_hash(struct ifpga_sec_mgr *imgr,
> + u32 hash_addr, u8 *hash,
> + unsigned int size)
> +{
> + struct m10bmc_sec *sec = imgr->priv;
> + unsigned int stride = regmap_get_reg_stride(sec->m10bmc->regmap);
> + int ret;
> +
> + ret = m10bmc_raw_bulk_read(sec->m10bmc, hash_addr,
> + hash, size / stride);
> + if (ret)
> + dev_err(sec->dev, "bulk_read of 0x%x failed %d",
> + hash_addr, ret);
> +
> + return ret;
> +}
> +
> +static int m10bmc_bmc_root_entry_hash(struct ifpga_sec_mgr *imgr,
> + u8 *hash, unsigned int size)
> +{
> + return m10bmc_root_entry_hash(imgr, BMC_REH_ADDR, hash, size);
> +}
> +
> +static int m10bmc_sr_root_entry_hash(struct ifpga_sec_mgr *imgr,
> + u8 *hash, unsigned int size)
> +{
> + return m10bmc_root_entry_hash(imgr, SR_REH_ADDR, hash, size);
> +}
> +
> +static int m10bmc_pr_root_entry_hash(struct ifpga_sec_mgr *imgr,
> + u8 *hash, unsigned int size)
> +{
> + return m10bmc_root_entry_hash(imgr, PR_REH_ADDR, hash, size);
> +}
> +
> +static const struct ifpga_sec_mgr_ops m10bmc_iops = {
> + .bmc_root_entry_hash = m10bmc_bmc_root_entry_hash,
> + .sr_root_entry_hash = m10bmc_sr_root_entry_hash,
> + .pr_root_entry_hash = m10bmc_pr_root_entry_hash,
> + .bmc_reh_size = m10bmc_bmc_reh_size,
> + .sr_reh_size = m10bmc_sr_reh_size,
> + .pr_reh_size = m10bmc_pr_reh_size,
> +};
> +
> +static int m10bmc_secure_probe(struct platform_device *pdev)
> +{
> + struct ifpga_sec_mgr *imgr;
> + struct m10bmc_sec *sec;
> + int ret;
> +
> + sec = devm_kzalloc(&pdev->dev, sizeof(*sec), GFP_KERNEL);
> + if (!sec)
> + return -ENOMEM;
> +
> + sec->dev = &pdev->dev;
> + sec->m10bmc = dev_get_drvdata(pdev->dev.parent);
> + dev_set_drvdata(&pdev->dev, sec);
> +
> + imgr = devm_ifpga_sec_mgr_create(sec->dev, "Max10 BMC Security Manager",
> + &m10bmc_iops, sec);
> + if (!imgr) {
> + dev_err(sec->dev,
> + "Security manager failed to start: %d\n", ret);
> + return -ENOMEM;
> + }
> +
> + sec->imgr = imgr;
> +
> + return ifpga_sec_mgr_register(imgr);
> +}
> +
> +static int m10bmc_secure_remove(struct platform_device *pdev)
> +{
> + struct m10bmc_sec *sec = dev_get_drvdata(&pdev->dev);
> +
> + ifpga_sec_mgr_unregister(sec->imgr);
> +
> + return 0;
> +}
> +
> +static struct platform_driver intel_m10bmc_secure_driver = {
> + .probe = m10bmc_secure_probe,
> + .remove = m10bmc_secure_remove,
> + .driver = {
> + .name = "n3000bmc-secure",
> + },
> +};
> +module_platform_driver(intel_m10bmc_secure_driver);
> +
> +MODULE_ALIAS("platform:n3000bmc-secure");
> +MODULE_AUTHOR("Intel Corporation");
> +MODULE_DESCRIPTION("Intel MAX10 BMC secure engine");
Maybe "... secure update"
Tom
> +MODULE_LICENSE("GPL v2");
