[PATCH v14 0/4] Intel MAX10 BMC Secure Update Driver

[PATCH v14 0/4] Intel MAX10 BMC Secure Update Driver

[Russ Weight]

The Intel MAX10 BMC Secure Update driver instantiates the FPGA Image
Load class driver and provides the callback functions required to
support secure updates on Intel n3000 PAC devices. This driver is
implemented as a sub-driver of the Intel MAX10 BMC mfd driver.

This driver interacts with the HW secure update engine of the FPGA
card BMC in order to transfer new FPGA and BMC images to FLASH on
the FPGA card so that they will be automatically loaded when the
FPGA card reboots. Security is enforced by hardware and firmware.
The MAX10 BMC Secure Update driver interacts with the firmware to
initiate an update, pass in the necessary data, and collect status
on the update.

This driver provides sysfs files for displaying the flash count, the
root entry hashes (REH), and the code-signing-key (CSK) cancellation
vectors.

These patches are dependent on other patches that are under review.
If you want to apply and compile these patches on linux-next, please
apply these patches first:

(6 patches) https://marc.info/?l=linux-fpga&m=163115393232140&w=2

Changelog v13 -> v14:
  - Changed symbol and text references to reflect the renaming of the
    Security Manager Class driver to FPGA Image Load.

Changelog v12 -> v13:
  - Updated copyright to 2021
  - Updated Date and KernelVersion fields in ABI documentation
  - Call updated fpga_sec_mgr_register() and fpga_sec_mgr_unregister()
    functions instead of devm_fpga_sec_mgr_create() and
    devm_fpga_sec_mgr_register().

Changelog v11 -> v12:
  - Updated Date and KernelVersion fields in ABI documentation
  - Removed size parameter from the write_blk() op. m10bmc_sec_write_blk()
    no longer has a size parameter, and the block size is determined
    in this (the lower-level) driver.

Changelog v10 -> v11:
  - Added Reviewed-by tag to patch #1

Changelog v9 -> v10:
  - Changed the path expressions in the sysfs documentation to
    replace the n3000 reference with something more generic to
    accomodate other devices that use the same driver.

Changelog v8 -> v9:
  - Rebased to 5.12-rc2 next
  - Updated Date and KernelVersion in ABI documentation

Changelog v7 -> v8:
  - Spit out patch "mfd: intel-m10-bmc: support for MAX10 BMC Secure
    Updates" and submitted it separately:
    https://marc.info/?l=linux-kernel&m=161126987101096&w=2

Changelog v6 -> v7:
  - Rebased patches for 5.11-rc2
  - Updated Date and KernelVersion in ABI documentation

Changelog v5 -> v6:
  - Added WARN_ON() prior to several calls to regmap_bulk_read()
    to assert that the (SIZE / stride) calculations did not result
    in remainders.
  - Changed the (size / stride) calculation in regmap_bulk_write()
    call to ensure that we don't write one less than intended.
  - Changed flash_count_show() parameter list to achieve
    reverse-christmas tree format.
  - Removed unnecessary call to rsu_check_complete() in
    m10bmc_sec_poll_complete() and changed while loop to
    do/while loop.
  - Initialized auth_result and doorbell to HW_ERRINFO_POISON
    in m10bmc_sec_hw_errinfo() and removed unnecessary if statements.

Changelog v4 -> v5:
  - Renamed sysfs node user_flash_count to flash_count and updated
    the sysfs documentation accordingly to more accurately descirbe
    the purpose of the count.

Changelog v3 -> v4:
  - Moved sysfs files for displaying the flash count, the root
    entry hashes (REH), and the code-signing-key (CSK) cancellation
    vectors from the FPGA Security Manager class driver to this
    driver (as they are not generic enough for the class driver).
  - Added a new ABI documentation file with informtaion about the
    new sysfs entries: sysfs-driver-intel-m10-bmc-secure
  - Updated the MAINTAINERS file to add the new ABI documentation
    file: sysfs-driver-intel-m10-bmc-secure
  - Removed unnecessary ret variable from m10bmc_secure_probe()
  - Incorporated new devm_fpga_sec_mgr_register() function into
    m10bmc_secure_probe() and removed the m10bmc_secure_remove()
    function.

Changelog v2 -> v3:
  - Changed "MAX10 BMC Security Engine driver" to "MAX10 BMC Secure
    Update driver"
  - Changed from "Intel FPGA Security Manager" to FPGA Security Manager"
  - Changed: iops -> sops, imgr -> smgr, IFPGA_ -> FPGA_, ifpga_ to fpga_
  - Removed wrapper functions (m10bmc_raw_*, m10bmc_sys_*). The
    underlying functions are now called directly.
  - Changed "_root_entry_hash" to "_reh", with a comment explaining
    what reh is.
  - Renamed get_csk_vector() to m10bmc_csk_vector()
  - Changed calling functions of functions that return "enum fpga_sec_err"
    to check for (ret != FPGA_SEC_ERR_NONE) instead of (ret)

Changelog v1 -> v2:
  - These patches were previously submitted as part of a larger V1
    patch set under the title "Intel FPGA Security Manager Class Driver".
  - Grouped all changes to include/linux/mfd/intel-m10-bmc.h into a
    single patch: "mfd: intel-m10-bmc: support for MAX10 BMC Security
    Engine".
  - 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().
  - Replaced small function-creation macros for explicit function
    declarations.
  - Bug fix for the get_csk_vector() function to properly apply the
    stride variable in calls to m10bmc_raw_bulk_read().
  - Added m10bmc_ prefix to functions in m10bmc_iops structure
  - Implemented HW_ERRINFO_POISON for m10bmc_sec_hw_errinfo() to
    ensure that corresponding bits are set to 1 if we are unable
    to read the doorbell or auth_result registers.
  - Added comments and additional code cleanup per V1 review.

Russ Weight (4):
  fpga: m10bmc-sec: create max10 bmc secure update driver
  fpga: m10bmc-sec: expose max10 flash update count
  fpga: m10bmc-sec: expose max10 canceled keys in sysfs
  fpga: m10bmc-sec: add max10 secure update functions

 .../testing/sysfs-driver-intel-m10-bmc-secure |  61 ++
 MAINTAINERS                                   |   2 +
 drivers/fpga/Kconfig                          |  11 +
 drivers/fpga/Makefile                         |   3 +
 drivers/fpga/intel-m10-bmc-secure.c           | 538 ++++++++++++++++++
 5 files changed, 615 insertions(+)
 create mode 100644 Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
 create mode 100644 drivers/fpga/intel-m10-bmc-secure.c

-- 
2.25.1

[PATCH v14 1/4] fpga: m10bmc-sec: create max10 bmc secure update driver

[Russ Weight]

Create a sub driver for the FPGA Card BMC in order to support secure
updates.  This sub-driver will invoke an instance of the FPGA Image Load
class driver for the image load portion of the update.

This patch creates the MAX10 BMC Secure Update driver and provides sysfs
files 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@intel.com>
Reviewed-by: Tom Rix <trix@redhat.com>
---
v14:
  - Changed symbol and text references to reflect the renaming of the
    Security Manager Class driver to FPGA Image Load.
v13:
  - Updated copyright to 2021
  - Updated ABI documentation date and kernel version
  - Call updated fpga_sec_mgr_register() and fpga_sec_mgr_unregister()
    functions instead of devm_fpga_sec_mgr_create() and
    devm_fpga_sec_mgr_register().
v12:
  - Updated Date and KernelVersion fields in ABI documentation
v11:
  - Added Reviewed-by tag
v10:
  - Changed the path expressions in the sysfs documentation to
    replace the n3000 reference with something more generic to
    accomodate other devices that use the same driver.
v9:
  - Rebased to 5.12-rc2 next
  - Updated Date and KernelVersion in ABI documentation
v8:
  - Previously patch 2/6, otherwise no change
v7:
  - Updated Date and KernelVersion in ABI documentation
v6:
  - Added WARN_ON() call for (sha_num_bytes / stride) to assert
    that the proper count is passed to regmap_bulk_read().
v5:
  - No change
v4:
  - Moved sysfs files for displaying the root entry hashes (REH)
    from the FPGA Security Manager class driver to here. The
    m10bmc_reh() and m10bmc_reh_size() functions are removed and
    the functionality from these functions is moved into a
    show_root_entry_hash() function for displaying the REHs.
  - Added ABI documentation for the new sysfs entries:
    sysfs-driver-intel-m10-bmc-secure
  - Updated the MAINTAINERS file to add the new ABI documentation
    file: sysfs-driver-intel-m10-bmc-secure
  - Removed unnecessary ret variable from m10bmc_secure_probe()
  - Incorporated new devm_fpga_sec_mgr_register() function into
    m10bmc_secure_probe() and removed the m10bmc_secure_remove()
    function.
v3:
  - Changed from "Intel FPGA Security Manager" to FPGA Security Manager"
  - Changed: iops -> sops, imgr -> smgr, IFPGA_ -> FPGA_, ifpga_ to fpga_
  - Changed "MAX10 BMC Secure Engine driver" to "MAX10 BMC Secure
    Update driver"
  - Removed wrapper functions (m10bmc_raw_*, m10bmc_sys_*). The
    underlying functions are now called directly.
  - Changed "_root_entry_hash" to "_reh", with a comment explaining
    what reh is.
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().
---
 .../testing/sysfs-driver-intel-m10-bmc-secure |  29 ++++
 MAINTAINERS                                   |   2 +
 drivers/fpga/Kconfig                          |  11 ++
 drivers/fpga/Makefile                         |   3 +
 drivers/fpga/intel-m10-bmc-secure.c           | 145 ++++++++++++++++++
 5 files changed, 190 insertions(+)
 create mode 100644 Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
 create mode 100644 drivers/fpga/intel-m10-bmc-secure.c

diff --git a/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
new file mode 100644
index 000000000000..363403ce992d
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
@@ -0,0 +1,29 @@
+What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/sr_root_entry_hash
+Date:		Aug 2021
+KernelVersion:	5.15
+Contact:	Russ Weight <russell.h.weight@intel.com>
+Description:	Read only. Returns the root entry hash for the static
+		region if one is programmed, else it returns the
+		string: "hash not programmed".  This file is only
+		visible if the underlying device supports it.
+		Format: "0x%x".
+
+What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/pr_root_entry_hash
+Date:		Aug 2021
+KernelVersion:	5.15
+Contact:	Russ Weight <russell.h.weight@intel.com>
+Description:	Read only. Returns the root entry hash for the partial
+		reconfiguration region if one is programmed, else it
+		returns the string: "hash not programmed".  This file
+		is only visible if the underlying device supports it.
+		Format: "0x%x".
+
+What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/bmc_root_entry_hash
+Date:		Aug 2021
+KernelVersion:	5.15
+Contact:	Russ Weight <russell.h.weight@intel.com>
+Description:	Read only. Returns the root entry hash for the BMC image
+		if one is programmed, else it returns the string:
+		"hash not programmed".  This file is only visible if the
+		underlying device supports it.
+		Format: "0x%x".
diff --git a/MAINTAINERS b/MAINTAINERS
index e3fbc1bde9bc..cf93835b4775 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7363,8 +7363,10 @@ M:	Russ Weight <russell.h.weight@intel.com>
 L:	linux-fpga@vger.kernel.org
 S:	Maintained
 F:	Documentation/ABI/testing/sysfs-class-fpga-image-load
+F:	Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
 F:	Documentation/fpga/fpga-image-load.rst
 F:	drivers/fpga/fpga-image-load.c
+F:	drivers/fpga/intel-m10-bmc-secure.c
 F:	include/linux/fpga/fpga-image-load.h
 F:	include/uapi/linux/fpga-image-load.h
 
diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
index c12a14e62fff..9d25b1ec03cd 100644
--- a/drivers/fpga/Kconfig
+++ b/drivers/fpga/Kconfig
@@ -253,4 +253,15 @@ config FPGA_IMAGE_LOAD
 	  and/or the device itself to authenticate and disposition the
 	  image data.
 
+config FPGA_M10_BMC_SECURE
+	tristate "Intel MAX10 BMC Secure Update driver"
+	depends on MFD_INTEL_M10_BMC && FPGA_IMAGE_LOAD
+	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 adf228ee4f5e..8d4c1869ac4c 100644
--- a/drivers/fpga/Makefile
+++ b/drivers/fpga/Makefile
@@ -25,6 +25,9 @@ obj-$(CONFIG_ALTERA_PR_IP_CORE_PLAT)    += altera-pr-ip-core-plat.o
 # FPGA Image Load Framework
 obj-$(CONFIG_FPGA_IMAGE_LOAD)		+= fpga-image-load.o
 
+# FPGA Secure Update Drivers
+obj-$(CONFIG_FPGA_M10_BMC_SECURE)	+= intel-m10-bmc-secure.o
+
 # FPGA Bridge Drivers
 obj-$(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..03fc571f40f2
--- /dev/null
+++ b/drivers/fpga/intel-m10-bmc-secure.c
@@ -0,0 +1,145 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Intel Max10 Board Management Controller Secure Update Driver
+ *
+ * Copyright (C) 2019-2021 Intel Corporation. All rights reserved.
+ *
+ */
+#include <linux/bitfield.h>
+#include <linux/device.h>
+#include <linux/fpga/fpga-image-load.h>
+#include <linux/mfd/intel-m10-bmc.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+struct m10bmc_sec {
+	struct device *dev;
+	struct intel_m10bmc *m10bmc;
+	struct fpga_image_load *imgld;
+};
+
+/* Root Entry Hash (REH) support */
+#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 ssize_t
+show_root_entry_hash(struct device *dev, u32 exp_magic,
+		     u32 prog_addr, u32 reh_addr, char *buf)
+{
+	struct m10bmc_sec *sec = dev_get_drvdata(dev);
+	unsigned int stride = regmap_get_reg_stride(sec->m10bmc->regmap);
+	int sha_num_bytes, i, cnt, ret;
+	u8 hash[REH_SHA384_SIZE];
+	u32 magic;
+
+	ret = m10bmc_raw_read(sec->m10bmc, prog_addr, &magic);
+	if (ret)
+		return ret;
+
+	dev_dbg(dev, "%s magic 0x%08x\n", __func__, magic);
+
+	if (FIELD_GET(REH_MAGIC, magic) != exp_magic)
+		return sysfs_emit(buf, "hash not programmed\n");
+
+	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;
+	}
+
+	WARN_ON(sha_num_bytes % stride);
+	ret = regmap_bulk_read(sec->m10bmc->regmap, reh_addr,
+			       hash, sha_num_bytes / stride);
+	if (ret) {
+		dev_err(dev, "failed to read root entry hash: %x cnt %x: %d\n",
+			reh_addr, sha_num_bytes / stride, ret);
+		return ret;
+	}
+
+	cnt = sprintf(buf, "0x");
+	for (i = 0; i < sha_num_bytes; i++)
+		cnt += sprintf(buf + cnt, "%02x", hash[i]);
+	cnt += sprintf(buf + cnt, "\n");
+
+	return cnt;
+}
+
+#define DEVICE_ATTR_SEC_REH_RO(_name, _magic, _prog_addr, _reh_addr) \
+static ssize_t _name##_root_entry_hash_show(struct device *dev, \
+					    struct device_attribute *attr, \
+					    char *buf) \
+{ return show_root_entry_hash(dev, _magic, _prog_addr, _reh_addr, buf); } \
+static DEVICE_ATTR_RO(_name##_root_entry_hash)
+
+DEVICE_ATTR_SEC_REH_RO(bmc, BMC_PROG_MAGIC, BMC_PROG_ADDR, BMC_REH_ADDR);
+DEVICE_ATTR_SEC_REH_RO(sr, SR_PROG_MAGIC, SR_PROG_ADDR, SR_REH_ADDR);
+DEVICE_ATTR_SEC_REH_RO(pr, PR_PROG_MAGIC, PR_PROG_ADDR, PR_REH_ADDR);
+
+static struct attribute *m10bmc_security_attrs[] = {
+	&dev_attr_bmc_root_entry_hash.attr,
+	&dev_attr_sr_root_entry_hash.attr,
+	&dev_attr_pr_root_entry_hash.attr,
+	NULL,
+};
+
+static struct attribute_group m10bmc_security_attr_group = {
+	.name = "security",
+	.attrs = m10bmc_security_attrs,
+};
+
+static const struct attribute_group *m10bmc_sec_attr_groups[] = {
+	&m10bmc_security_attr_group,
+	NULL,
+};
+
+static const struct fpga_image_load_ops m10bmc_lops = { };
+
+static int m10bmc_secure_probe(struct platform_device *pdev)
+{
+	struct fpga_image_load *imgld;
+	struct m10bmc_sec *sec;
+
+	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);
+
+	imgld = fpga_image_load_register(sec->dev, &m10bmc_lops, sec);
+	if (IS_ERR(imgld)) {
+		dev_err(sec->dev, "FPGA Image Load driver failed to start\n");
+		return PTR_ERR(imgld);
+	}
+
+	sec->imgld = imgld;
+	return 0;
+}
+
+static int m10bmc_secure_remove(struct platform_device *pdev)
+{
+	struct m10bmc_sec *sec = dev_get_drvdata(&pdev->dev);
+
+	fpga_image_load_unregister(sec->imgld);
+	return 0;
+}
+
+static struct platform_driver intel_m10bmc_secure_driver = {
+	.probe = m10bmc_secure_probe,
+	.remove = m10bmc_secure_remove,
+	.driver = {
+		.name = "n3000bmc-secure",
+		.dev_groups = m10bmc_sec_attr_groups,
+	},
+};
+module_platform_driver(intel_m10bmc_secure_driver);
+
+MODULE_ALIAS("platform:n3000bmc-secure");
+MODULE_AUTHOR("Intel Corporation");
+MODULE_DESCRIPTION("Intel MAX10 BMC Secure Update");
+MODULE_LICENSE("GPL v2");
-- 
2.25.1

[PATCH v14 2/4] fpga: m10bmc-sec: expose max10 flash update count

[Russ Weight]

Extend the MAX10 BMC Secure Update driver to provide a sysfs file to
expose the flash update count for the FPGA user image.

Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Reviewed-by: Tom Rix <trix@redhat.com>
---
v14:
  - No change
v13:
  - Updated ABI documentation date and kernel version
v12:
  - Updated Date and KernelVersion fields in ABI documentation
v11:
  - No change
v10:
  - Changed the path expression in the sysfs documentation to
    replace the n3000 reference with something more generic to
    accomodate other devices that use the same driver.
v9:
  - Rebased to 5.12-rc2 next
  - Updated Date and KernelVersion in ABI documentation
v8:
  - Previously patch 3/6, otherwise no change
v7:
  - Updated Date and KernelVersion in ABI documentation
v6:
  - Changed flash_count_show() parameter list to achieve
    reverse-christmas tree format.
  - Added WARN_ON() call for (FLASH_COUNT_SIZE / stride) to ensure
    that the proper count is passed to regmap_bulk_read().
v5:
  - Renamed sysfs node user_flash_count to flash_count and updated the
    sysfs documentation accordingly.
v4:
  - Moved the sysfs file for displaying the flash count from the
    FPGA Security Manager class driver to here. The
    m10bmc_user_flash_count() function is removed and the
    functionality is moved into a user_flash_count_show()
    function.
  - Added ABI documentation for the new sysfs entry
v3:
  - Changed: iops -> sops, imgr -> smgr, IFPGA_ -> FPGA_, ifpga_ to fpga_
  - Changed "MAX10 BMC Secure Engine driver" to "MAX10 BMC Secure Update
    driver"
  - Removed wrapper functions (m10bmc_raw_*, m10bmc_sys_*). The
    underlying functions are now called directly.
v2:
  - Renamed get_qspi_flash_count() to m10bmc_user_flash_count()
  - Minor code cleanup per review comments
  - Added m10bmc_ prefix to functions in m10bmc_iops structure
---
 .../testing/sysfs-driver-intel-m10-bmc-secure |  8 ++++
 drivers/fpga/intel-m10-bmc-secure.c           | 37 +++++++++++++++++++
 2 files changed, 45 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
index 363403ce992d..22dc43de1f4f 100644
--- a/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
+++ b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
@@ -27,3 +27,11 @@ Description:	Read only. Returns the root entry hash for the BMC image
 		"hash not programmed".  This file is only visible if the
 		underlying device supports it.
 		Format: "0x%x".
+
+What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/flash_count
+Date:		Aug 2021
+KernelVersion:	5.15
+Contact:	Russ Weight <russell.h.weight@intel.com>
+Description:	Read only. Returns number of times the secure update
+		staging area has been flashed.
+		Format: "%u".
diff --git a/drivers/fpga/intel-m10-bmc-secure.c b/drivers/fpga/intel-m10-bmc-secure.c
index 03fc571f40f2..88996b525e65 100644
--- a/drivers/fpga/intel-m10-bmc-secure.c
+++ b/drivers/fpga/intel-m10-bmc-secure.c
@@ -11,6 +11,7 @@
 #include <linux/mfd/intel-m10-bmc.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
+#include <linux/slab.h>
 
 struct m10bmc_sec {
 	struct device *dev;
@@ -79,7 +80,43 @@ DEVICE_ATTR_SEC_REH_RO(bmc, BMC_PROG_MAGIC, BMC_PROG_ADDR, BMC_REH_ADDR);
 DEVICE_ATTR_SEC_REH_RO(sr, SR_PROG_MAGIC, SR_PROG_ADDR, SR_REH_ADDR);
 DEVICE_ATTR_SEC_REH_RO(pr, PR_PROG_MAGIC, PR_PROG_ADDR, PR_REH_ADDR);
 
+#define FLASH_COUNT_SIZE 4096	/* count stored as inverted bit vector */
+
+static ssize_t flash_count_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct m10bmc_sec *sec = dev_get_drvdata(dev);
+	unsigned int stride, num_bits;
+	u8 *flash_buf;
+	int cnt, ret;
+
+	stride = regmap_get_reg_stride(sec->m10bmc->regmap);
+	num_bits = FLASH_COUNT_SIZE * 8;
+
+	flash_buf = kmalloc(FLASH_COUNT_SIZE, GFP_KERNEL);
+	if (!flash_buf)
+		return -ENOMEM;
+
+	WARN_ON(FLASH_COUNT_SIZE % stride);
+	ret = regmap_bulk_read(sec->m10bmc->regmap, STAGING_FLASH_COUNT,
+			       flash_buf, FLASH_COUNT_SIZE / stride);
+	if (ret) {
+		dev_err(sec->dev,
+			"failed to read flash count: %x cnt %x: %d\n",
+			STAGING_FLASH_COUNT, FLASH_COUNT_SIZE / stride, ret);
+		goto exit_free;
+	}
+	cnt = num_bits - bitmap_weight((unsigned long *)flash_buf, num_bits);
+
+exit_free:
+	kfree(flash_buf);
+
+	return ret ? : sysfs_emit(buf, "%u\n", cnt);
+}
+static DEVICE_ATTR_RO(flash_count);
+
 static struct attribute *m10bmc_security_attrs[] = {
+	&dev_attr_flash_count.attr,
 	&dev_attr_bmc_root_entry_hash.attr,
 	&dev_attr_sr_root_entry_hash.attr,
 	&dev_attr_pr_root_entry_hash.attr,
-- 
2.25.1

[PATCH v14 3/4] fpga: m10bmc-sec: expose max10 canceled keys in sysfs

[Russ Weight]

Extend the MAX10 BMC Secure Update driver to provide sysfs files to
expose the canceled code signing key (CSK) bit vectors. These use
the standard bitmap list format (e.g. 1,2-6,9).

Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Reviewed-by: Tom Rix <trix@redhat.com>
---
v14:
  - No changes
v13:
  - Updated ABI documentation date and kernel version
v12:
  - Updated Date and KernelVersion fields in ABI documentation
v11:
  - No change
v10:
  - Changed the path expressions in the sysfs documentation to
    replace the n3000 reference with something more generic to
    accomodate other devices that use the same driver.
v9:
  - Rebased to 5.12-rc2 next
  - Updated Date and KernelVersion in ABI documentation
v8:
  - Previously patch 4/6, otherwise no change
v7:
  - Updated Date and KernelVersion in ABI documentation
v6:
  - Added WARN_ON() call for (size / stride) to ensure
    that the proper count is passed to regmap_bulk_read().
v5:
  - No change
v4:
  - Moved sysfs files for displaying the code-signing-key (CSK)
    cancellation vectors from the FPGA Security Manger class driver
    to here. The m10bmc_csk_vector() and m10bmc_csk_cancel_nbits()
    functions are removed and the functionality from these functions
    is moved into a show_canceled_csk() function for for displaying
    the CSK vectors.
  - Added ABI documentation for new sysfs entries
v3:
  - Changed: iops -> sops, imgr -> smgr, IFPGA_ -> FPGA_, ifpga_ to fpga_
  - Changed "MAX10 BMC Secure Engine driver" to "MAX10 BMC Secure Update
    driver"
  - Removed wrapper functions (m10bmc_raw_*, m10bmc_sys_*). The
    underlying functions are now called directly.
  - Renamed get_csk_vector() to m10bmc_csk_vector()
v2:
  - Replaced small function-creation macros for explicit function
    declarations.
  - Fixed get_csk_vector() function to properly apply the stride
    variable in calls to m10bmc_raw_bulk_read()
  - Added m10bmc_ prefix to functions in m10bmc_iops structure
---
 .../testing/sysfs-driver-intel-m10-bmc-secure | 24 ++++++++++
 drivers/fpga/intel-m10-bmc-secure.c           | 48 +++++++++++++++++++
 2 files changed, 72 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
index 22dc43de1f4f..5664b2d26a9a 100644
--- a/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
+++ b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
@@ -28,6 +28,30 @@ Description:	Read only. Returns the root entry hash for the BMC image
 		underlying device supports it.
 		Format: "0x%x".
 
+What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/sr_canceled_csks
+Date:		Aug 2021
+KernelVersion:	5.15
+Contact:	Russ Weight <russell.h.weight@intel.com>
+Description:	Read only. Returns a list of indices for canceled code
+		signing keys for the static region. The standard bitmap
+		list format is used (e.g. "1,2-6,9").
+
+What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/pr_canceled_csks
+Date:		Aug 2021
+KernelVersion:	5.15
+Contact:	Russ Weight <russell.h.weight@intel.com>
+Description:	Read only. Returns a list of indices for canceled code
+		signing keys for the partial reconfiguration region. The
+		standard bitmap list format is used (e.g. "1,2-6,9").
+
+What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/bmc_canceled_csks
+Date:		Aug 2021
+KernelVersion:	5.15
+Contact:	Russ Weight <russell.h.weight@intel.com>
+Description:	Read only. Returns a list of indices for canceled code
+		signing keys for the BMC.  The standard bitmap list format
+		is used (e.g. "1,2-6,9").
+
 What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/flash_count
 Date:		Aug 2021
 KernelVersion:	5.15
diff --git a/drivers/fpga/intel-m10-bmc-secure.c b/drivers/fpga/intel-m10-bmc-secure.c
index 88996b525e65..ae1383d13bfc 100644
--- a/drivers/fpga/intel-m10-bmc-secure.c
+++ b/drivers/fpga/intel-m10-bmc-secure.c
@@ -80,6 +80,51 @@ DEVICE_ATTR_SEC_REH_RO(bmc, BMC_PROG_MAGIC, BMC_PROG_ADDR, BMC_REH_ADDR);
 DEVICE_ATTR_SEC_REH_RO(sr, SR_PROG_MAGIC, SR_PROG_ADDR, SR_REH_ADDR);
 DEVICE_ATTR_SEC_REH_RO(pr, PR_PROG_MAGIC, PR_PROG_ADDR, PR_REH_ADDR);
 
+#define CSK_BIT_LEN		128U
+#define CSK_32ARRAY_SIZE	DIV_ROUND_UP(CSK_BIT_LEN, 32)
+
+static ssize_t
+show_canceled_csk(struct device *dev, u32 addr, char *buf)
+{
+	unsigned int i, stride, size = CSK_32ARRAY_SIZE * sizeof(u32);
+	struct m10bmc_sec *sec = dev_get_drvdata(dev);
+	DECLARE_BITMAP(csk_map, CSK_BIT_LEN);
+	__le32 csk_le32[CSK_32ARRAY_SIZE];
+	u32 csk32[CSK_32ARRAY_SIZE];
+	int ret;
+
+	stride = regmap_get_reg_stride(sec->m10bmc->regmap);
+
+	WARN_ON(size % stride);
+	ret = regmap_bulk_read(sec->m10bmc->regmap, addr, csk_le32,
+			       size / stride);
+	if (ret) {
+		dev_err(sec->dev, "failed to read CSK vector: %x cnt %x: %d\n",
+			addr, size / stride, ret);
+		return ret;
+	}
+
+	for (i = 0; i < CSK_32ARRAY_SIZE; i++)
+		csk32[i] = le32_to_cpu(((csk_le32[i])));
+
+	bitmap_from_arr32(csk_map, csk32, CSK_BIT_LEN);
+	bitmap_complement(csk_map, csk_map, CSK_BIT_LEN);
+	return bitmap_print_to_pagebuf(1, buf, csk_map, CSK_BIT_LEN);
+}
+
+#define DEVICE_ATTR_SEC_CSK_RO(_name, _addr) \
+static ssize_t _name##_canceled_csks_show(struct device *dev, \
+					  struct device_attribute *attr, \
+					  char *buf) \
+{ return show_canceled_csk(dev, _addr, buf); } \
+static DEVICE_ATTR_RO(_name##_canceled_csks)
+
+#define CSK_VEC_OFFSET 0x34
+
+DEVICE_ATTR_SEC_CSK_RO(bmc, BMC_PROG_ADDR + CSK_VEC_OFFSET);
+DEVICE_ATTR_SEC_CSK_RO(sr, SR_PROG_ADDR + CSK_VEC_OFFSET);
+DEVICE_ATTR_SEC_CSK_RO(pr, PR_PROG_ADDR + CSK_VEC_OFFSET);
+
 #define FLASH_COUNT_SIZE 4096	/* count stored as inverted bit vector */
 
 static ssize_t flash_count_show(struct device *dev,
@@ -120,6 +165,9 @@ static struct attribute *m10bmc_security_attrs[] = {
 	&dev_attr_bmc_root_entry_hash.attr,
 	&dev_attr_sr_root_entry_hash.attr,
 	&dev_attr_pr_root_entry_hash.attr,
+	&dev_attr_sr_canceled_csks.attr,
+	&dev_attr_pr_canceled_csks.attr,
+	&dev_attr_bmc_canceled_csks.attr,
 	NULL,
 };
 
-- 
2.25.1

[PATCH v14 4/4] fpga: m10bmc-sec: add max10 secure update functions

[Russ Weight]

Invoke an instance of the FPGA Image Load driver and extend the MAX10
BMC Secure Update driver to include the functions that enable secure
updates of BMC images, FPGA images, etc.

Signed-off-by: Russ Weight <russell.h.weight@intel.com>
---
v14:
  - Changed symbol names to reflect the renaming of the Security Manager
    Class driver to FPGA Image Load.
v13:
  - No change
v12:
  - Updated Date and KernelVersion fields in ABI documentation
  - Removed size parameter from the write_blk() op. m10bmc_sec_write_blk()
    no longer has a size parameter, and the block size is determined
    in this (the lower-level) driver.
v11:
  - No change
v10:
  - No change
v9:
  - No change
v8:
  - Previously patch 5/6, otherwise no change
v7:
  - No change
v6:
  - Changed (size / stride) calculation to ((size + stride - 1) / stride)
    to ensure that the proper count is passed to regmap_bulk_write().
  - Removed unnecessary call to rsu_check_complete() in
    m10bmc_sec_poll_complete() and changed while loop to
    do/while loop.
v5:
  - No change
v4:
  - No change
v3:
  - Changed: iops -> sops, imgr -> smgr, IFPGA_ -> FPGA_, ifpga_ to fpga_
  - Changed "MAX10 BMC Secure Engine driver" to "MAX10 BMC Secure Update
    driver"
  - Removed wrapper functions (m10bmc_raw_*, m10bmc_sys_*). The
    underlying functions are now called directly.
  - Changed calling functions of functions that return "enum fpga_sec_err"
    to check for (ret != FPGA_SEC_ERR_NONE) instead of (ret)
v2:
  - Reworked the rsu_start_done() function to make it more readable
  - Reworked while-loop condition/content in rsu_prog_ready()
  - Minor code cleanup per review comments
  - Added a comment to the m10bmc_sec_poll_complete() function to
    explain the context (could take 30+ minutes to complete).
  - Added m10bmc_ prefix to functions in m10bmc_iops structure
  - Moved MAX10 BMC address and function definitions to a separate
    patch.
---
 drivers/fpga/intel-m10-bmc-secure.c | 310 +++++++++++++++++++++++++++-
 1 file changed, 309 insertions(+), 1 deletion(-)

diff --git a/drivers/fpga/intel-m10-bmc-secure.c b/drivers/fpga/intel-m10-bmc-secure.c
index ae1383d13bfc..025655684d00 100644
--- a/drivers/fpga/intel-m10-bmc-secure.c
+++ b/drivers/fpga/intel-m10-bmc-secure.c
@@ -181,7 +181,315 @@ static const struct attribute_group *m10bmc_sec_attr_groups[] = {
 	NULL,
 };
 
-static const struct fpga_image_load_ops m10bmc_lops = { };
+static void log_error_regs(struct m10bmc_sec *sec, u32 doorbell)
+{
+	u32 auth_result;
+
+	dev_err(sec->dev, "RSU error status: 0x%08x\n", doorbell);
+
+	if (!m10bmc_sys_read(sec->m10bmc, M10BMC_AUTH_RESULT, &auth_result))
+		dev_err(sec->dev, "RSU auth result: 0x%08x\n", auth_result);
+}
+
+static enum fpga_image_err rsu_check_idle(struct m10bmc_sec *sec)
+{
+	u32 doorbell;
+	int ret;
+
+	ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
+	if (ret)
+		return FPGA_IMAGE_ERR_RW_ERROR;
+
+	if (rsu_prog(doorbell) != RSU_PROG_IDLE &&
+	    rsu_prog(doorbell) != RSU_PROG_RSU_DONE) {
+		log_error_regs(sec, doorbell);
+		return FPGA_IMAGE_ERR_BUSY;
+	}
+
+	return FPGA_IMAGE_ERR_NONE;
+}
+
+static inline bool rsu_start_done(u32 doorbell)
+{
+	u32 status, progress;
+
+	if (doorbell & DRBL_RSU_REQUEST)
+		return false;
+
+	status = rsu_stat(doorbell);
+	if (status == RSU_STAT_ERASE_FAIL || status == RSU_STAT_WEAROUT)
+		return true;
+
+	progress = rsu_prog(doorbell);
+	if (progress != RSU_PROG_IDLE && progress != RSU_PROG_RSU_DONE)
+		return true;
+
+	return false;
+}
+
+static enum fpga_image_err rsu_update_init(struct m10bmc_sec *sec)
+{
+	u32 doorbell, status;
+	int ret;
+
+	ret = regmap_update_bits(sec->m10bmc->regmap,
+				 M10BMC_SYS_BASE + M10BMC_DOORBELL,
+				 DRBL_RSU_REQUEST | DRBL_HOST_STATUS,
+				 DRBL_RSU_REQUEST |
+				 FIELD_PREP(DRBL_HOST_STATUS,
+					    HOST_STATUS_IDLE));
+	if (ret)
+		return FPGA_IMAGE_ERR_RW_ERROR;
+
+	ret = regmap_read_poll_timeout(sec->m10bmc->regmap,
+				       M10BMC_SYS_BASE + M10BMC_DOORBELL,
+				       doorbell,
+				       rsu_start_done(doorbell),
+				       NIOS_HANDSHAKE_INTERVAL_US,
+				       NIOS_HANDSHAKE_TIMEOUT_US);
+
+	if (ret == -ETIMEDOUT) {
+		log_error_regs(sec, doorbell);
+		return FPGA_IMAGE_ERR_TIMEOUT;
+	} else if (ret) {
+		return FPGA_IMAGE_ERR_RW_ERROR;
+	}
+
+	status = rsu_stat(doorbell);
+	if (status == RSU_STAT_WEAROUT) {
+		dev_warn(sec->dev, "Excessive flash update count detected\n");
+		return FPGA_IMAGE_ERR_WEAROUT;
+	} else if (status == RSU_STAT_ERASE_FAIL) {
+		log_error_regs(sec, doorbell);
+		return FPGA_IMAGE_ERR_HW_ERROR;
+	}
+
+	return FPGA_IMAGE_ERR_NONE;
+}
+
+static enum fpga_image_err rsu_prog_ready(struct m10bmc_sec *sec)
+{
+	unsigned long poll_timeout;
+	u32 doorbell, progress;
+	int ret;
+
+	ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
+	if (ret)
+		return FPGA_IMAGE_ERR_RW_ERROR;
+
+	poll_timeout = jiffies + msecs_to_jiffies(RSU_PREP_TIMEOUT_MS);
+	while (rsu_prog(doorbell) == RSU_PROG_PREPARE) {
+		msleep(RSU_PREP_INTERVAL_MS);
+		if (time_after(jiffies, poll_timeout))
+			break;
+
+		ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
+		if (ret)
+			return FPGA_IMAGE_ERR_RW_ERROR;
+	}
+
+	progress = rsu_prog(doorbell);
+	if (progress == RSU_PROG_PREPARE) {
+		log_error_regs(sec, doorbell);
+		return FPGA_IMAGE_ERR_TIMEOUT;
+	} else if (progress != RSU_PROG_READY) {
+		log_error_regs(sec, doorbell);
+		return FPGA_IMAGE_ERR_HW_ERROR;
+	}
+
+	return FPGA_IMAGE_ERR_NONE;
+}
+
+static enum fpga_image_err rsu_send_data(struct m10bmc_sec *sec)
+{
+	u32 doorbell;
+	int ret;
+
+	ret = regmap_update_bits(sec->m10bmc->regmap,
+				 M10BMC_SYS_BASE + M10BMC_DOORBELL,
+				 DRBL_HOST_STATUS,
+				 FIELD_PREP(DRBL_HOST_STATUS,
+					    HOST_STATUS_WRITE_DONE));
+	if (ret)
+		return FPGA_IMAGE_ERR_RW_ERROR;
+
+	ret = regmap_read_poll_timeout(sec->m10bmc->regmap,
+				       M10BMC_SYS_BASE + M10BMC_DOORBELL,
+				       doorbell,
+				       rsu_prog(doorbell) != RSU_PROG_READY,
+				       NIOS_HANDSHAKE_INTERVAL_US,
+				       NIOS_HANDSHAKE_TIMEOUT_US);
+
+	if (ret == -ETIMEDOUT) {
+		log_error_regs(sec, doorbell);
+		return FPGA_IMAGE_ERR_TIMEOUT;
+	} else if (ret) {
+		return FPGA_IMAGE_ERR_RW_ERROR;
+	}
+
+	switch (rsu_stat(doorbell)) {
+	case RSU_STAT_NORMAL:
+	case RSU_STAT_NIOS_OK:
+	case RSU_STAT_USER_OK:
+	case RSU_STAT_FACTORY_OK:
+		break;
+	default:
+		log_error_regs(sec, doorbell);
+		return FPGA_IMAGE_ERR_HW_ERROR;
+	}
+
+	return FPGA_IMAGE_ERR_NONE;
+}
+
+static int rsu_check_complete(struct m10bmc_sec *sec, u32 *doorbell)
+{
+	if (m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, doorbell))
+		return -EIO;
+
+	switch (rsu_stat(*doorbell)) {
+	case RSU_STAT_NORMAL:
+	case RSU_STAT_NIOS_OK:
+	case RSU_STAT_USER_OK:
+	case RSU_STAT_FACTORY_OK:
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	switch (rsu_prog(*doorbell)) {
+	case RSU_PROG_IDLE:
+	case RSU_PROG_RSU_DONE:
+		return 0;
+	case RSU_PROG_AUTHENTICATING:
+	case RSU_PROG_COPYING:
+	case RSU_PROG_UPDATE_CANCEL:
+	case RSU_PROG_PROGRAM_KEY_HASH:
+		return -EAGAIN;
+	default:
+		return -EINVAL;
+	}
+}
+
+static enum fpga_image_err m10bmc_sec_prepare(struct fpga_image_load *imgld)
+{
+	struct m10bmc_sec *sec = imgld->priv;
+	enum fpga_image_err ret;
+
+	if (imgld->remaining_size > M10BMC_STAGING_SIZE)
+		return FPGA_IMAGE_ERR_INVALID_SIZE;
+
+	ret = rsu_check_idle(sec);
+	if (ret != FPGA_IMAGE_ERR_NONE)
+		return ret;
+
+	ret = rsu_update_init(sec);
+	if (ret != FPGA_IMAGE_ERR_NONE)
+		return ret;
+
+	return rsu_prog_ready(sec);
+}
+
+#define WRITE_BLOCK_SIZE 0x4000 /* Update remaining_size every 0x4000 bytes */
+
+static enum fpga_image_err
+m10bmc_sec_write_blk(struct fpga_image_load *imgld, u32 offset)
+{
+	struct m10bmc_sec *sec = imgld->priv;
+	unsigned int stride = regmap_get_reg_stride(sec->m10bmc->regmap);
+	u32 doorbell, blk_size;
+	int ret;
+
+	ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
+	if (ret) {
+		return FPGA_IMAGE_ERR_RW_ERROR;
+	} else if (rsu_prog(doorbell) != RSU_PROG_READY) {
+		log_error_regs(sec, doorbell);
+		return FPGA_IMAGE_ERR_HW_ERROR;
+	}
+
+	blk_size = min_t(u32, imgld->remaining_size, WRITE_BLOCK_SIZE);
+	ret = regmap_bulk_write(sec->m10bmc->regmap,
+				M10BMC_STAGING_BASE + offset,
+				(void *)imgld->data + offset,
+				(blk_size + stride - 1) / stride);
+
+	if (ret)
+		return FPGA_IMAGE_ERR_RW_ERROR;
+
+	imgld->remaining_size -= blk_size;
+	return FPGA_IMAGE_ERR_NONE;
+}
+
+/*
+ * m10bmc_sec_poll_complete() is called after handing things off to
+ * the BMC firmware. Depending on the type of update, it could be
+ * 30+ minutes before the BMC firmware completes the update. The
+ * imgld->driver_unload check allows the driver to be unloaded,
+ * but the BMC firmware will continue the update and no further
+ * secure updates can be started for this device until the update
+ * is complete.
+ */
+static enum fpga_image_err m10bmc_sec_poll_complete(struct fpga_image_load *imgld)
+{
+	struct m10bmc_sec *sec = imgld->priv;
+	unsigned long poll_timeout;
+	enum fpga_image_err result;
+	u32 doorbell;
+	int ret;
+
+	result = rsu_send_data(sec);
+	if (result != FPGA_IMAGE_ERR_NONE)
+		return result;
+
+	poll_timeout = jiffies + msecs_to_jiffies(RSU_COMPLETE_TIMEOUT_MS);
+	do {
+		msleep(RSU_COMPLETE_INTERVAL_MS);
+		ret = rsu_check_complete(sec, &doorbell);
+		if (imgld->driver_unload)
+			return FPGA_IMAGE_ERR_CANCELED;
+	} while (ret == -EAGAIN && !time_after(jiffies, poll_timeout));
+
+	if (ret == -EAGAIN) {
+		log_error_regs(sec, doorbell);
+		return FPGA_IMAGE_ERR_TIMEOUT;
+	} else if (ret == -EIO) {
+		return FPGA_IMAGE_ERR_RW_ERROR;
+	} else if (ret) {
+		log_error_regs(sec, doorbell);
+		return FPGA_IMAGE_ERR_HW_ERROR;
+	}
+
+	return FPGA_IMAGE_ERR_NONE;
+}
+
+static enum fpga_image_err m10bmc_sec_cancel(struct fpga_image_load *imgld)
+{
+	struct m10bmc_sec *sec = imgld->priv;
+	u32 doorbell;
+	int ret;
+
+	ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
+	if (ret)
+		return FPGA_IMAGE_ERR_RW_ERROR;
+
+	if (rsu_prog(doorbell) != RSU_PROG_READY)
+		return FPGA_IMAGE_ERR_BUSY;
+
+	ret = regmap_update_bits(sec->m10bmc->regmap,
+				 M10BMC_SYS_BASE + M10BMC_DOORBELL,
+				 DRBL_HOST_STATUS,
+				 FIELD_PREP(DRBL_HOST_STATUS,
+					    HOST_STATUS_ABORT_RSU));
+
+	return ret ? FPGA_IMAGE_ERR_RW_ERROR : FPGA_IMAGE_ERR_NONE;
+}
+
+static const struct fpga_image_load_ops m10bmc_lops = {
+	.prepare = m10bmc_sec_prepare,
+	.write_blk = m10bmc_sec_write_blk,
+	.poll_complete = m10bmc_sec_poll_complete,
+	.cancel = m10bmc_sec_cancel,
+};
 
 static int m10bmc_secure_probe(struct platform_device *pdev)
 {
-- 
2.25.1

Re: [PATCH v14 1/4] fpga: m10bmc-sec: create max10 bmc secure update driver

[Xu Yilun]

On Thu, Sep 09, 2021 at 04:33:01PM -0700, Russ Weight wrote:
> Create a sub driver for the FPGA Card BMC in order to support secure
> updates.  This sub-driver will invoke an instance of the FPGA Image Load
> class driver for the image load portion of the update.
> 
> This patch creates the MAX10 BMC Secure Update driver and provides sysfs
> files 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@intel.com>
> Reviewed-by: Tom Rix <trix@redhat.com>
> ---
> v14:
>   - Changed symbol and text references to reflect the renaming of the
>     Security Manager Class driver to FPGA Image Load.
> v13:
>   - Updated copyright to 2021
>   - Updated ABI documentation date and kernel version
>   - Call updated fpga_sec_mgr_register() and fpga_sec_mgr_unregister()
>     functions instead of devm_fpga_sec_mgr_create() and
>     devm_fpga_sec_mgr_register().
> v12:
>   - Updated Date and KernelVersion fields in ABI documentation
> v11:
>   - Added Reviewed-by tag
> v10:
>   - Changed the path expressions in the sysfs documentation to
>     replace the n3000 reference with something more generic to
>     accomodate other devices that use the same driver.
> v9:
>   - Rebased to 5.12-rc2 next
>   - Updated Date and KernelVersion in ABI documentation
> v8:
>   - Previously patch 2/6, otherwise no change
> v7:
>   - Updated Date and KernelVersion in ABI documentation
> v6:
>   - Added WARN_ON() call for (sha_num_bytes / stride) to assert
>     that the proper count is passed to regmap_bulk_read().
> v5:
>   - No change
> v4:
>   - Moved sysfs files for displaying the root entry hashes (REH)
>     from the FPGA Security Manager class driver to here. The
>     m10bmc_reh() and m10bmc_reh_size() functions are removed and
>     the functionality from these functions is moved into a
>     show_root_entry_hash() function for displaying the REHs.
>   - Added ABI documentation for the new sysfs entries:
>     sysfs-driver-intel-m10-bmc-secure
>   - Updated the MAINTAINERS file to add the new ABI documentation
>     file: sysfs-driver-intel-m10-bmc-secure
>   - Removed unnecessary ret variable from m10bmc_secure_probe()
>   - Incorporated new devm_fpga_sec_mgr_register() function into
>     m10bmc_secure_probe() and removed the m10bmc_secure_remove()
>     function.
> v3:
>   - Changed from "Intel FPGA Security Manager" to FPGA Security Manager"
>   - Changed: iops -> sops, imgr -> smgr, IFPGA_ -> FPGA_, ifpga_ to fpga_
>   - Changed "MAX10 BMC Secure Engine driver" to "MAX10 BMC Secure
>     Update driver"
>   - Removed wrapper functions (m10bmc_raw_*, m10bmc_sys_*). The
>     underlying functions are now called directly.
>   - Changed "_root_entry_hash" to "_reh", with a comment explaining
>     what reh is.
> 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().
> ---
>  .../testing/sysfs-driver-intel-m10-bmc-secure |  29 ++++
>  MAINTAINERS                                   |   2 +
>  drivers/fpga/Kconfig                          |  11 ++
>  drivers/fpga/Makefile                         |   3 +
>  drivers/fpga/intel-m10-bmc-secure.c           | 145 ++++++++++++++++++
>  5 files changed, 190 insertions(+)
>  create mode 100644 Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
>  create mode 100644 drivers/fpga/intel-m10-bmc-secure.c
> 
> diff --git a/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
> new file mode 100644
> index 000000000000..363403ce992d
> --- /dev/null
> +++ b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
> @@ -0,0 +1,29 @@
> +What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/sr_root_entry_hash
> +Date:		Aug 2021
> +KernelVersion:	5.15
> +Contact:	Russ Weight <russell.h.weight@intel.com>
> +Description:	Read only. Returns the root entry hash for the static
> +		region if one is programmed, else it returns the
> +		string: "hash not programmed".  This file is only
> +		visible if the underlying device supports it.
> +		Format: "0x%x".
> +
> +What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/pr_root_entry_hash
> +Date:		Aug 2021
> +KernelVersion:	5.15
> +Contact:	Russ Weight <russell.h.weight@intel.com>
> +Description:	Read only. Returns the root entry hash for the partial
> +		reconfiguration region if one is programmed, else it
> +		returns the string: "hash not programmed".  This file
> +		is only visible if the underlying device supports it.
> +		Format: "0x%x".
> +
> +What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/bmc_root_entry_hash
> +Date:		Aug 2021
> +KernelVersion:	5.15
> +Contact:	Russ Weight <russell.h.weight@intel.com>
> +Description:	Read only. Returns the root entry hash for the BMC image
> +		if one is programmed, else it returns the string:
> +		"hash not programmed".  This file is only visible if the
> +		underlying device supports it.
> +		Format: "0x%x".
> diff --git a/MAINTAINERS b/MAINTAINERS
> index e3fbc1bde9bc..cf93835b4775 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -7363,8 +7363,10 @@ M:	Russ Weight <russell.h.weight@intel.com>
>  L:	linux-fpga@vger.kernel.org
>  S:	Maintained
>  F:	Documentation/ABI/testing/sysfs-class-fpga-image-load
> +F:	Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure

Should we change the name of the driver? Some keywords like "image load"
or "firmware update" should be in the name.

Thanks,
Yilun

>  F:	Documentation/fpga/fpga-image-load.rst
>  F:	drivers/fpga/fpga-image-load.c
> +F:	drivers/fpga/intel-m10-bmc-secure.c
>  F:	include/linux/fpga/fpga-image-load.h
>  F:	include/uapi/linux/fpga-image-load.h
>  
> diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
> index c12a14e62fff..9d25b1ec03cd 100644
> --- a/drivers/fpga/Kconfig
> +++ b/drivers/fpga/Kconfig
> @@ -253,4 +253,15 @@ config FPGA_IMAGE_LOAD
>  	  and/or the device itself to authenticate and disposition the
>  	  image data.
>  
> +config FPGA_M10_BMC_SECURE
> +	tristate "Intel MAX10 BMC Secure Update driver"
> +	depends on MFD_INTEL_M10_BMC && FPGA_IMAGE_LOAD
> +	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 adf228ee4f5e..8d4c1869ac4c 100644
> --- a/drivers/fpga/Makefile
> +++ b/drivers/fpga/Makefile
> @@ -25,6 +25,9 @@ obj-$(CONFIG_ALTERA_PR_IP_CORE_PLAT)    += altera-pr-ip-core-plat.o
>  # FPGA Image Load Framework
>  obj-$(CONFIG_FPGA_IMAGE_LOAD)		+= fpga-image-load.o
>  
> +# FPGA Secure Update Drivers
> +obj-$(CONFIG_FPGA_M10_BMC_SECURE)	+= intel-m10-bmc-secure.o
> +
>  # FPGA Bridge Drivers
>  obj-$(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..03fc571f40f2
> --- /dev/null
> +++ b/drivers/fpga/intel-m10-bmc-secure.c
> @@ -0,0 +1,145 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Intel Max10 Board Management Controller Secure Update Driver
> + *
> + * Copyright (C) 2019-2021 Intel Corporation. All rights reserved.
> + *
> + */
> +#include <linux/bitfield.h>
> +#include <linux/device.h>
> +#include <linux/fpga/fpga-image-load.h>
> +#include <linux/mfd/intel-m10-bmc.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +
> +struct m10bmc_sec {
> +	struct device *dev;
> +	struct intel_m10bmc *m10bmc;
> +	struct fpga_image_load *imgld;
> +};
> +
> +/* Root Entry Hash (REH) support */
> +#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 ssize_t
> +show_root_entry_hash(struct device *dev, u32 exp_magic,
> +		     u32 prog_addr, u32 reh_addr, char *buf)
> +{
> +	struct m10bmc_sec *sec = dev_get_drvdata(dev);
> +	unsigned int stride = regmap_get_reg_stride(sec->m10bmc->regmap);
> +	int sha_num_bytes, i, cnt, ret;
> +	u8 hash[REH_SHA384_SIZE];
> +	u32 magic;
> +
> +	ret = m10bmc_raw_read(sec->m10bmc, prog_addr, &magic);
> +	if (ret)
> +		return ret;
> +
> +	dev_dbg(dev, "%s magic 0x%08x\n", __func__, magic);
> +
> +	if (FIELD_GET(REH_MAGIC, magic) != exp_magic)
> +		return sysfs_emit(buf, "hash not programmed\n");
> +
> +	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;
> +	}
> +
> +	WARN_ON(sha_num_bytes % stride);
> +	ret = regmap_bulk_read(sec->m10bmc->regmap, reh_addr,
> +			       hash, sha_num_bytes / stride);
> +	if (ret) {
> +		dev_err(dev, "failed to read root entry hash: %x cnt %x: %d\n",
> +			reh_addr, sha_num_bytes / stride, ret);
> +		return ret;
> +	}
> +
> +	cnt = sprintf(buf, "0x");
> +	for (i = 0; i < sha_num_bytes; i++)
> +		cnt += sprintf(buf + cnt, "%02x", hash[i]);
> +	cnt += sprintf(buf + cnt, "\n");
> +
> +	return cnt;
> +}
> +
> +#define DEVICE_ATTR_SEC_REH_RO(_name, _magic, _prog_addr, _reh_addr) \
> +static ssize_t _name##_root_entry_hash_show(struct device *dev, \
> +					    struct device_attribute *attr, \
> +					    char *buf) \
> +{ return show_root_entry_hash(dev, _magic, _prog_addr, _reh_addr, buf); } \
> +static DEVICE_ATTR_RO(_name##_root_entry_hash)
> +
> +DEVICE_ATTR_SEC_REH_RO(bmc, BMC_PROG_MAGIC, BMC_PROG_ADDR, BMC_REH_ADDR);
> +DEVICE_ATTR_SEC_REH_RO(sr, SR_PROG_MAGIC, SR_PROG_ADDR, SR_REH_ADDR);
> +DEVICE_ATTR_SEC_REH_RO(pr, PR_PROG_MAGIC, PR_PROG_ADDR, PR_REH_ADDR);
> +
> +static struct attribute *m10bmc_security_attrs[] = {
> +	&dev_attr_bmc_root_entry_hash.attr,
> +	&dev_attr_sr_root_entry_hash.attr,
> +	&dev_attr_pr_root_entry_hash.attr,
> +	NULL,
> +};
> +
> +static struct attribute_group m10bmc_security_attr_group = {
> +	.name = "security",
> +	.attrs = m10bmc_security_attrs,
> +};
> +
> +static const struct attribute_group *m10bmc_sec_attr_groups[] = {
> +	&m10bmc_security_attr_group,
> +	NULL,
> +};
> +
> +static const struct fpga_image_load_ops m10bmc_lops = { };
> +
> +static int m10bmc_secure_probe(struct platform_device *pdev)
> +{
> +	struct fpga_image_load *imgld;
> +	struct m10bmc_sec *sec;
> +
> +	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);
> +
> +	imgld = fpga_image_load_register(sec->dev, &m10bmc_lops, sec);
> +	if (IS_ERR(imgld)) {
> +		dev_err(sec->dev, "FPGA Image Load driver failed to start\n");
> +		return PTR_ERR(imgld);
> +	}
> +
> +	sec->imgld = imgld;
> +	return 0;
> +}
> +
> +static int m10bmc_secure_remove(struct platform_device *pdev)
> +{
> +	struct m10bmc_sec *sec = dev_get_drvdata(&pdev->dev);
> +
> +	fpga_image_load_unregister(sec->imgld);
> +	return 0;
> +}
> +
> +static struct platform_driver intel_m10bmc_secure_driver = {
> +	.probe = m10bmc_secure_probe,
> +	.remove = m10bmc_secure_remove,
> +	.driver = {
> +		.name = "n3000bmc-secure",
> +		.dev_groups = m10bmc_sec_attr_groups,
> +	},
> +};
> +module_platform_driver(intel_m10bmc_secure_driver);
> +
> +MODULE_ALIAS("platform:n3000bmc-secure");
> +MODULE_AUTHOR("Intel Corporation");
> +MODULE_DESCRIPTION("Intel MAX10 BMC Secure Update");
> +MODULE_LICENSE("GPL v2");
> -- 
> 2.25.1

Re: [PATCH v14 4/4] fpga: m10bmc-sec: add max10 secure update functions

[Xu Yilun]

On Thu, Sep 09, 2021 at 04:33:04PM -0700, Russ Weight wrote:
> Invoke an instance of the FPGA Image Load driver and extend the MAX10
> BMC Secure Update driver to include the functions that enable secure
> updates of BMC images, FPGA images, etc.
> 
> Signed-off-by: Russ Weight <russell.h.weight@intel.com>
> ---
> v14:
>   - Changed symbol names to reflect the renaming of the Security Manager
>     Class driver to FPGA Image Load.
> v13:
>   - No change
> v12:
>   - Updated Date and KernelVersion fields in ABI documentation
>   - Removed size parameter from the write_blk() op. m10bmc_sec_write_blk()
>     no longer has a size parameter, and the block size is determined
>     in this (the lower-level) driver.
> v11:
>   - No change
> v10:
>   - No change
> v9:
>   - No change
> v8:
>   - Previously patch 5/6, otherwise no change
> v7:
>   - No change
> v6:
>   - Changed (size / stride) calculation to ((size + stride - 1) / stride)
>     to ensure that the proper count is passed to regmap_bulk_write().
>   - Removed unnecessary call to rsu_check_complete() in
>     m10bmc_sec_poll_complete() and changed while loop to
>     do/while loop.
> v5:
>   - No change
> v4:
>   - No change
> v3:
>   - Changed: iops -> sops, imgr -> smgr, IFPGA_ -> FPGA_, ifpga_ to fpga_
>   - Changed "MAX10 BMC Secure Engine driver" to "MAX10 BMC Secure Update
>     driver"
>   - Removed wrapper functions (m10bmc_raw_*, m10bmc_sys_*). The
>     underlying functions are now called directly.
>   - Changed calling functions of functions that return "enum fpga_sec_err"
>     to check for (ret != FPGA_SEC_ERR_NONE) instead of (ret)
> v2:
>   - Reworked the rsu_start_done() function to make it more readable
>   - Reworked while-loop condition/content in rsu_prog_ready()
>   - Minor code cleanup per review comments
>   - Added a comment to the m10bmc_sec_poll_complete() function to
>     explain the context (could take 30+ minutes to complete).
>   - Added m10bmc_ prefix to functions in m10bmc_iops structure
>   - Moved MAX10 BMC address and function definitions to a separate
>     patch.
> ---
>  drivers/fpga/intel-m10-bmc-secure.c | 310 +++++++++++++++++++++++++++-
>  1 file changed, 309 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/fpga/intel-m10-bmc-secure.c b/drivers/fpga/intel-m10-bmc-secure.c
> index ae1383d13bfc..025655684d00 100644
> --- a/drivers/fpga/intel-m10-bmc-secure.c
> +++ b/drivers/fpga/intel-m10-bmc-secure.c
> @@ -181,7 +181,315 @@ static const struct attribute_group *m10bmc_sec_attr_groups[] = {
>  	NULL,
>  };
>  
> -static const struct fpga_image_load_ops m10bmc_lops = { };
> +static void log_error_regs(struct m10bmc_sec *sec, u32 doorbell)
> +{
> +	u32 auth_result;
> +
> +	dev_err(sec->dev, "RSU error status: 0x%08x\n", doorbell);
> +
> +	if (!m10bmc_sys_read(sec->m10bmc, M10BMC_AUTH_RESULT, &auth_result))
> +		dev_err(sec->dev, "RSU auth result: 0x%08x\n", auth_result);
> +}
> +
> +static enum fpga_image_err rsu_check_idle(struct m10bmc_sec *sec)
> +{
> +	u32 doorbell;
> +	int ret;
> +
> +	ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
> +	if (ret)
> +		return FPGA_IMAGE_ERR_RW_ERROR;
> +
> +	if (rsu_prog(doorbell) != RSU_PROG_IDLE &&
> +	    rsu_prog(doorbell) != RSU_PROG_RSU_DONE) {
> +		log_error_regs(sec, doorbell);
> +		return FPGA_IMAGE_ERR_BUSY;
> +	}
> +
> +	return FPGA_IMAGE_ERR_NONE;
> +}
> +
> +static inline bool rsu_start_done(u32 doorbell)
> +{
> +	u32 status, progress;
> +
> +	if (doorbell & DRBL_RSU_REQUEST)
> +		return false;
> +
> +	status = rsu_stat(doorbell);
> +	if (status == RSU_STAT_ERASE_FAIL || status == RSU_STAT_WEAROUT)
> +		return true;
> +
> +	progress = rsu_prog(doorbell);
> +	if (progress != RSU_PROG_IDLE && progress != RSU_PROG_RSU_DONE)
> +		return true;
> +
> +	return false;
> +}
> +
> +static enum fpga_image_err rsu_update_init(struct m10bmc_sec *sec)
> +{
> +	u32 doorbell, status;
> +	int ret;
> +
> +	ret = regmap_update_bits(sec->m10bmc->regmap,
> +				 M10BMC_SYS_BASE + M10BMC_DOORBELL,
> +				 DRBL_RSU_REQUEST | DRBL_HOST_STATUS,
> +				 DRBL_RSU_REQUEST |
> +				 FIELD_PREP(DRBL_HOST_STATUS,
> +					    HOST_STATUS_IDLE));
> +	if (ret)
> +		return FPGA_IMAGE_ERR_RW_ERROR;
> +
> +	ret = regmap_read_poll_timeout(sec->m10bmc->regmap,
> +				       M10BMC_SYS_BASE + M10BMC_DOORBELL,
> +				       doorbell,
> +				       rsu_start_done(doorbell),
> +				       NIOS_HANDSHAKE_INTERVAL_US,
> +				       NIOS_HANDSHAKE_TIMEOUT_US);
> +
> +	if (ret == -ETIMEDOUT) {
> +		log_error_regs(sec, doorbell);
> +		return FPGA_IMAGE_ERR_TIMEOUT;
> +	} else if (ret) {
> +		return FPGA_IMAGE_ERR_RW_ERROR;
> +	}
> +
> +	status = rsu_stat(doorbell);
> +	if (status == RSU_STAT_WEAROUT) {
> +		dev_warn(sec->dev, "Excessive flash update count detected\n");
> +		return FPGA_IMAGE_ERR_WEAROUT;
> +	} else if (status == RSU_STAT_ERASE_FAIL) {
> +		log_error_regs(sec, doorbell);
> +		return FPGA_IMAGE_ERR_HW_ERROR;
> +	}
> +
> +	return FPGA_IMAGE_ERR_NONE;
> +}
> +
> +static enum fpga_image_err rsu_prog_ready(struct m10bmc_sec *sec)
> +{
> +	unsigned long poll_timeout;
> +	u32 doorbell, progress;
> +	int ret;
> +
> +	ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
> +	if (ret)
> +		return FPGA_IMAGE_ERR_RW_ERROR;
> +
> +	poll_timeout = jiffies + msecs_to_jiffies(RSU_PREP_TIMEOUT_MS);
> +	while (rsu_prog(doorbell) == RSU_PROG_PREPARE) {
> +		msleep(RSU_PREP_INTERVAL_MS);
> +		if (time_after(jiffies, poll_timeout))
> +			break;
> +
> +		ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
> +		if (ret)
> +			return FPGA_IMAGE_ERR_RW_ERROR;
> +	}
> +
> +	progress = rsu_prog(doorbell);
> +	if (progress == RSU_PROG_PREPARE) {
> +		log_error_regs(sec, doorbell);
> +		return FPGA_IMAGE_ERR_TIMEOUT;
> +	} else if (progress != RSU_PROG_READY) {
> +		log_error_regs(sec, doorbell);
> +		return FPGA_IMAGE_ERR_HW_ERROR;
> +	}
> +
> +	return FPGA_IMAGE_ERR_NONE;
> +}
> +
> +static enum fpga_image_err rsu_send_data(struct m10bmc_sec *sec)
> +{
> +	u32 doorbell;
> +	int ret;
> +
> +	ret = regmap_update_bits(sec->m10bmc->regmap,
> +				 M10BMC_SYS_BASE + M10BMC_DOORBELL,
> +				 DRBL_HOST_STATUS,
> +				 FIELD_PREP(DRBL_HOST_STATUS,
> +					    HOST_STATUS_WRITE_DONE));
> +	if (ret)
> +		return FPGA_IMAGE_ERR_RW_ERROR;
> +
> +	ret = regmap_read_poll_timeout(sec->m10bmc->regmap,
> +				       M10BMC_SYS_BASE + M10BMC_DOORBELL,
> +				       doorbell,
> +				       rsu_prog(doorbell) != RSU_PROG_READY,
> +				       NIOS_HANDSHAKE_INTERVAL_US,
> +				       NIOS_HANDSHAKE_TIMEOUT_US);
> +
> +	if (ret == -ETIMEDOUT) {
> +		log_error_regs(sec, doorbell);
> +		return FPGA_IMAGE_ERR_TIMEOUT;
> +	} else if (ret) {
> +		return FPGA_IMAGE_ERR_RW_ERROR;
> +	}
> +
> +	switch (rsu_stat(doorbell)) {
> +	case RSU_STAT_NORMAL:
> +	case RSU_STAT_NIOS_OK:
> +	case RSU_STAT_USER_OK:
> +	case RSU_STAT_FACTORY_OK:
> +		break;
> +	default:
> +		log_error_regs(sec, doorbell);
> +		return FPGA_IMAGE_ERR_HW_ERROR;
> +	}
> +
> +	return FPGA_IMAGE_ERR_NONE;
> +}
> +
> +static int rsu_check_complete(struct m10bmc_sec *sec, u32 *doorbell)
> +{
> +	if (m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, doorbell))
> +		return -EIO;
> +
> +	switch (rsu_stat(*doorbell)) {
> +	case RSU_STAT_NORMAL:
> +	case RSU_STAT_NIOS_OK:
> +	case RSU_STAT_USER_OK:
> +	case RSU_STAT_FACTORY_OK:
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	switch (rsu_prog(*doorbell)) {
> +	case RSU_PROG_IDLE:
> +	case RSU_PROG_RSU_DONE:
> +		return 0;
> +	case RSU_PROG_AUTHENTICATING:
> +	case RSU_PROG_COPYING:
> +	case RSU_PROG_UPDATE_CANCEL:
> +	case RSU_PROG_PROGRAM_KEY_HASH:
> +		return -EAGAIN;
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +
> +static enum fpga_image_err m10bmc_sec_prepare(struct fpga_image_load *imgld)
> +{
> +	struct m10bmc_sec *sec = imgld->priv;
> +	enum fpga_image_err ret;
> +
> +	if (imgld->remaining_size > M10BMC_STAGING_SIZE)
> +		return FPGA_IMAGE_ERR_INVALID_SIZE;
> +
> +	ret = rsu_check_idle(sec);
> +	if (ret != FPGA_IMAGE_ERR_NONE)
> +		return ret;
> +
> +	ret = rsu_update_init(sec);
> +	if (ret != FPGA_IMAGE_ERR_NONE)
> +		return ret;
> +
> +	return rsu_prog_ready(sec);
> +}
> +
> +#define WRITE_BLOCK_SIZE 0x4000 /* Update remaining_size every 0x4000 bytes */
> +
> +static enum fpga_image_err
> +m10bmc_sec_write_blk(struct fpga_image_load *imgld, u32 offset)
> +{
> +	struct m10bmc_sec *sec = imgld->priv;
> +	unsigned int stride = regmap_get_reg_stride(sec->m10bmc->regmap);
> +	u32 doorbell, blk_size;
> +	int ret;
> +
> +	ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
> +	if (ret) {
> +		return FPGA_IMAGE_ERR_RW_ERROR;
> +	} else if (rsu_prog(doorbell) != RSU_PROG_READY) {
> +		log_error_regs(sec, doorbell);
> +		return FPGA_IMAGE_ERR_HW_ERROR;
> +	}
> +
> +	blk_size = min_t(u32, imgld->remaining_size, WRITE_BLOCK_SIZE);
> +	ret = regmap_bulk_write(sec->m10bmc->regmap,
> +				M10BMC_STAGING_BASE + offset,
> +				(void *)imgld->data + offset,
> +				(blk_size + stride - 1) / stride);
> +
> +	if (ret)
> +		return FPGA_IMAGE_ERR_RW_ERROR;
> +
> +	imgld->remaining_size -= blk_size;
> +	return FPGA_IMAGE_ERR_NONE;
> +}
> +
> +/*
> + * m10bmc_sec_poll_complete() is called after handing things off to
> + * the BMC firmware. Depending on the type of update, it could be
> + * 30+ minutes before the BMC firmware completes the update. The
> + * imgld->driver_unload check allows the driver to be unloaded,
> + * but the BMC firmware will continue the update and no further
> + * secure updates can be started for this device until the update
> + * is complete.
> + */
> +static enum fpga_image_err m10bmc_sec_poll_complete(struct fpga_image_load *imgld)
> +{
> +	struct m10bmc_sec *sec = imgld->priv;
> +	unsigned long poll_timeout;
> +	enum fpga_image_err result;
> +	u32 doorbell;
> +	int ret;
> +
> +	result = rsu_send_data(sec);
> +	if (result != FPGA_IMAGE_ERR_NONE)
> +		return result;
> +
> +	poll_timeout = jiffies + msecs_to_jiffies(RSU_COMPLETE_TIMEOUT_MS);
> +	do {
> +		msleep(RSU_COMPLETE_INTERVAL_MS);
> +		ret = rsu_check_complete(sec, &doorbell);
> +		if (imgld->driver_unload)
> +			return FPGA_IMAGE_ERR_CANCELED;

Why we return CANCELED error code to user when driver unload is
requested?

Users may think the update is failed and the old image is kept,
but in fact, the update continues and finally the old image is
replaced by the new one.

Thanks,
Yilun

> +	} while (ret == -EAGAIN && !time_after(jiffies, poll_timeout));
> +
> +	if (ret == -EAGAIN) {
> +		log_error_regs(sec, doorbell);
> +		return FPGA_IMAGE_ERR_TIMEOUT;
> +	} else if (ret == -EIO) {
> +		return FPGA_IMAGE_ERR_RW_ERROR;
> +	} else if (ret) {
> +		log_error_regs(sec, doorbell);
> +		return FPGA_IMAGE_ERR_HW_ERROR;
> +	}
> +
> +	return FPGA_IMAGE_ERR_NONE;
> +}
> +
> +static enum fpga_image_err m10bmc_sec_cancel(struct fpga_image_load *imgld)
> +{
> +	struct m10bmc_sec *sec = imgld->priv;
> +	u32 doorbell;
> +	int ret;
> +
> +	ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
> +	if (ret)
> +		return FPGA_IMAGE_ERR_RW_ERROR;
> +
> +	if (rsu_prog(doorbell) != RSU_PROG_READY)
> +		return FPGA_IMAGE_ERR_BUSY;
> +
> +	ret = regmap_update_bits(sec->m10bmc->regmap,
> +				 M10BMC_SYS_BASE + M10BMC_DOORBELL,
> +				 DRBL_HOST_STATUS,
> +				 FIELD_PREP(DRBL_HOST_STATUS,
> +					    HOST_STATUS_ABORT_RSU));
> +
> +	return ret ? FPGA_IMAGE_ERR_RW_ERROR : FPGA_IMAGE_ERR_NONE;
> +}
> +
> +static const struct fpga_image_load_ops m10bmc_lops = {
> +	.prepare = m10bmc_sec_prepare,
> +	.write_blk = m10bmc_sec_write_blk,
> +	.poll_complete = m10bmc_sec_poll_complete,
> +	.cancel = m10bmc_sec_cancel,
> +};
>  
>  static int m10bmc_secure_probe(struct platform_device *pdev)
>  {
> -- 
> 2.25.1

Re: [PATCH v14 1/4] fpga: m10bmc-sec: create max10 bmc secure update driver

[Russ Weight]

On 9/10/21 8:13 AM, Xu Yilun wrote:
> On Thu, Sep 09, 2021 at 04:33:01PM -0700, Russ Weight wrote:
>> Create a sub driver for the FPGA Card BMC in order to support secure
>> updates.  This sub-driver will invoke an instance of the FPGA Image Load
>> class driver for the image load portion of the update.
>>
>> This patch creates the MAX10 BMC Secure Update driver and provides sysfs
>> files 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@intel.com>
>> Reviewed-by: Tom Rix <trix@redhat.com>
>> ---
>> v14:
>>   - Changed symbol and text references to reflect the renaming of the
>>     Security Manager Class driver to FPGA Image Load.
>> v13:
>>   - Updated copyright to 2021
>>   - Updated ABI documentation date and kernel version
>>   - Call updated fpga_sec_mgr_register() and fpga_sec_mgr_unregister()
>>     functions instead of devm_fpga_sec_mgr_create() and
>>     devm_fpga_sec_mgr_register().
>> v12:
>>   - Updated Date and KernelVersion fields in ABI documentation
>> v11:
>>   - Added Reviewed-by tag
>> v10:
>>   - Changed the path expressions in the sysfs documentation to
>>     replace the n3000 reference with something more generic to
>>     accomodate other devices that use the same driver.
>> v9:
>>   - Rebased to 5.12-rc2 next
>>   - Updated Date and KernelVersion in ABI documentation
>> v8:
>>   - Previously patch 2/6, otherwise no change
>> v7:
>>   - Updated Date and KernelVersion in ABI documentation
>> v6:
>>   - Added WARN_ON() call for (sha_num_bytes / stride) to assert
>>     that the proper count is passed to regmap_bulk_read().
>> v5:
>>   - No change
>> v4:
>>   - Moved sysfs files for displaying the root entry hashes (REH)
>>     from the FPGA Security Manager class driver to here. The
>>     m10bmc_reh() and m10bmc_reh_size() functions are removed and
>>     the functionality from these functions is moved into a
>>     show_root_entry_hash() function for displaying the REHs.
>>   - Added ABI documentation for the new sysfs entries:
>>     sysfs-driver-intel-m10-bmc-secure
>>   - Updated the MAINTAINERS file to add the new ABI documentation
>>     file: sysfs-driver-intel-m10-bmc-secure
>>   - Removed unnecessary ret variable from m10bmc_secure_probe()
>>   - Incorporated new devm_fpga_sec_mgr_register() function into
>>     m10bmc_secure_probe() and removed the m10bmc_secure_remove()
>>     function.
>> v3:
>>   - Changed from "Intel FPGA Security Manager" to FPGA Security Manager"
>>   - Changed: iops -> sops, imgr -> smgr, IFPGA_ -> FPGA_, ifpga_ to fpga_
>>   - Changed "MAX10 BMC Secure Engine driver" to "MAX10 BMC Secure
>>     Update driver"
>>   - Removed wrapper functions (m10bmc_raw_*, m10bmc_sys_*). The
>>     underlying functions are now called directly.
>>   - Changed "_root_entry_hash" to "_reh", with a comment explaining
>>     what reh is.
>> 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().
>> ---
>>  .../testing/sysfs-driver-intel-m10-bmc-secure |  29 ++++
>>  MAINTAINERS                                   |   2 +
>>  drivers/fpga/Kconfig                          |  11 ++
>>  drivers/fpga/Makefile                         |   3 +
>>  drivers/fpga/intel-m10-bmc-secure.c           | 145 ++++++++++++++++++
>>  5 files changed, 190 insertions(+)
>>  create mode 100644 Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
>>  create mode 100644 drivers/fpga/intel-m10-bmc-secure.c
>>
>> diff --git a/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
>> new file mode 100644
>> index 000000000000..363403ce992d
>> --- /dev/null
>> +++ b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
>> @@ -0,0 +1,29 @@
>> +What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/sr_root_entry_hash
>> +Date:		Aug 2021
>> +KernelVersion:	5.15
>> +Contact:	Russ Weight <russell.h.weight@intel.com>
>> +Description:	Read only. Returns the root entry hash for the static
>> +		region if one is programmed, else it returns the
>> +		string: "hash not programmed".  This file is only
>> +		visible if the underlying device supports it.
>> +		Format: "0x%x".
>> +
>> +What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/pr_root_entry_hash
>> +Date:		Aug 2021
>> +KernelVersion:	5.15
>> +Contact:	Russ Weight <russell.h.weight@intel.com>
>> +Description:	Read only. Returns the root entry hash for the partial
>> +		reconfiguration region if one is programmed, else it
>> +		returns the string: "hash not programmed".  This file
>> +		is only visible if the underlying device supports it.
>> +		Format: "0x%x".
>> +
>> +What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/bmc_root_entry_hash
>> +Date:		Aug 2021
>> +KernelVersion:	5.15
>> +Contact:	Russ Weight <russell.h.weight@intel.com>
>> +Description:	Read only. Returns the root entry hash for the BMC image
>> +		if one is programmed, else it returns the string:
>> +		"hash not programmed".  This file is only visible if the
>> +		underlying device supports it.
>> +		Format: "0x%x".
>> diff --git a/MAINTAINERS b/MAINTAINERS
>> index e3fbc1bde9bc..cf93835b4775 100644
>> --- a/MAINTAINERS
>> +++ b/MAINTAINERS
>> @@ -7363,8 +7363,10 @@ M:	Russ Weight <russell.h.weight@intel.com>
>>  L:	linux-fpga@vger.kernel.org
>>  S:	Maintained
>>  F:	Documentation/ABI/testing/sysfs-class-fpga-image-load
>> +F:	Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
> Should we change the name of the driver? Some keywords like "image load"
> or "firmware update" should be in the name.

I considered that. The image-upload functionality is a subset of  this
driver. It also exposes security collateral via sysfs, and the image-load
triggers and power-on-image sysfs files will probably end up in this
driver too.

The current driver name is intel-m10-bmc-secure. Do we need to keep
"intel-m10-bmc" in the name?

intel-m10-bmc-sec-fw-update?
intel-m10-bmc-sec-update?

What do you think? Any other suggestions?

- Russ
>
> Thanks,
> Yilun
>
>>  F:	Documentation/fpga/fpga-image-load.rst
>>  F:	drivers/fpga/fpga-image-load.c
>> +F:	drivers/fpga/intel-m10-bmc-secure.c
>>  F:	include/linux/fpga/fpga-image-load.h
>>  F:	include/uapi/linux/fpga-image-load.h
>>  
>> diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
>> index c12a14e62fff..9d25b1ec03cd 100644
>> --- a/drivers/fpga/Kconfig
>> +++ b/drivers/fpga/Kconfig
>> @@ -253,4 +253,15 @@ config FPGA_IMAGE_LOAD
>>  	  and/or the device itself to authenticate and disposition the
>>  	  image data.
>>  
>> +config FPGA_M10_BMC_SECURE
>> +	tristate "Intel MAX10 BMC Secure Update driver"
>> +	depends on MFD_INTEL_M10_BMC && FPGA_IMAGE_LOAD
>> +	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 adf228ee4f5e..8d4c1869ac4c 100644
>> --- a/drivers/fpga/Makefile
>> +++ b/drivers/fpga/Makefile
>> @@ -25,6 +25,9 @@ obj-$(CONFIG_ALTERA_PR_IP_CORE_PLAT)    += altera-pr-ip-core-plat.o
>>  # FPGA Image Load Framework
>>  obj-$(CONFIG_FPGA_IMAGE_LOAD)		+= fpga-image-load.o
>>  
>> +# FPGA Secure Update Drivers
>> +obj-$(CONFIG_FPGA_M10_BMC_SECURE)	+= intel-m10-bmc-secure.o
>> +
>>  # FPGA Bridge Drivers
>>  obj-$(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..03fc571f40f2
>> --- /dev/null
>> +++ b/drivers/fpga/intel-m10-bmc-secure.c
>> @@ -0,0 +1,145 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Intel Max10 Board Management Controller Secure Update Driver
>> + *
>> + * Copyright (C) 2019-2021 Intel Corporation. All rights reserved.
>> + *
>> + */
>> +#include <linux/bitfield.h>
>> +#include <linux/device.h>
>> +#include <linux/fpga/fpga-image-load.h>
>> +#include <linux/mfd/intel-m10-bmc.h>
>> +#include <linux/module.h>
>> +#include <linux/platform_device.h>
>> +
>> +struct m10bmc_sec {
>> +	struct device *dev;
>> +	struct intel_m10bmc *m10bmc;
>> +	struct fpga_image_load *imgld;
>> +};
>> +
>> +/* Root Entry Hash (REH) support */
>> +#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 ssize_t
>> +show_root_entry_hash(struct device *dev, u32 exp_magic,
>> +		     u32 prog_addr, u32 reh_addr, char *buf)
>> +{
>> +	struct m10bmc_sec *sec = dev_get_drvdata(dev);
>> +	unsigned int stride = regmap_get_reg_stride(sec->m10bmc->regmap);
>> +	int sha_num_bytes, i, cnt, ret;
>> +	u8 hash[REH_SHA384_SIZE];
>> +	u32 magic;
>> +
>> +	ret = m10bmc_raw_read(sec->m10bmc, prog_addr, &magic);
>> +	if (ret)
>> +		return ret;
>> +
>> +	dev_dbg(dev, "%s magic 0x%08x\n", __func__, magic);
>> +
>> +	if (FIELD_GET(REH_MAGIC, magic) != exp_magic)
>> +		return sysfs_emit(buf, "hash not programmed\n");
>> +
>> +	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;
>> +	}
>> +
>> +	WARN_ON(sha_num_bytes % stride);
>> +	ret = regmap_bulk_read(sec->m10bmc->regmap, reh_addr,
>> +			       hash, sha_num_bytes / stride);
>> +	if (ret) {
>> +		dev_err(dev, "failed to read root entry hash: %x cnt %x: %d\n",
>> +			reh_addr, sha_num_bytes / stride, ret);
>> +		return ret;
>> +	}
>> +
>> +	cnt = sprintf(buf, "0x");
>> +	for (i = 0; i < sha_num_bytes; i++)
>> +		cnt += sprintf(buf + cnt, "%02x", hash[i]);
>> +	cnt += sprintf(buf + cnt, "\n");
>> +
>> +	return cnt;
>> +}
>> +
>> +#define DEVICE_ATTR_SEC_REH_RO(_name, _magic, _prog_addr, _reh_addr) \
>> +static ssize_t _name##_root_entry_hash_show(struct device *dev, \
>> +					    struct device_attribute *attr, \
>> +					    char *buf) \
>> +{ return show_root_entry_hash(dev, _magic, _prog_addr, _reh_addr, buf); } \
>> +static DEVICE_ATTR_RO(_name##_root_entry_hash)
>> +
>> +DEVICE_ATTR_SEC_REH_RO(bmc, BMC_PROG_MAGIC, BMC_PROG_ADDR, BMC_REH_ADDR);
>> +DEVICE_ATTR_SEC_REH_RO(sr, SR_PROG_MAGIC, SR_PROG_ADDR, SR_REH_ADDR);
>> +DEVICE_ATTR_SEC_REH_RO(pr, PR_PROG_MAGIC, PR_PROG_ADDR, PR_REH_ADDR);
>> +
>> +static struct attribute *m10bmc_security_attrs[] = {
>> +	&dev_attr_bmc_root_entry_hash.attr,
>> +	&dev_attr_sr_root_entry_hash.attr,
>> +	&dev_attr_pr_root_entry_hash.attr,
>> +	NULL,
>> +};
>> +
>> +static struct attribute_group m10bmc_security_attr_group = {
>> +	.name = "security",
>> +	.attrs = m10bmc_security_attrs,
>> +};
>> +
>> +static const struct attribute_group *m10bmc_sec_attr_groups[] = {
>> +	&m10bmc_security_attr_group,
>> +	NULL,
>> +};
>> +
>> +static const struct fpga_image_load_ops m10bmc_lops = { };
>> +
>> +static int m10bmc_secure_probe(struct platform_device *pdev)
>> +{
>> +	struct fpga_image_load *imgld;
>> +	struct m10bmc_sec *sec;
>> +
>> +	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);
>> +
>> +	imgld = fpga_image_load_register(sec->dev, &m10bmc_lops, sec);
>> +	if (IS_ERR(imgld)) {
>> +		dev_err(sec->dev, "FPGA Image Load driver failed to start\n");
>> +		return PTR_ERR(imgld);
>> +	}
>> +
>> +	sec->imgld = imgld;
>> +	return 0;
>> +}
>> +
>> +static int m10bmc_secure_remove(struct platform_device *pdev)
>> +{
>> +	struct m10bmc_sec *sec = dev_get_drvdata(&pdev->dev);
>> +
>> +	fpga_image_load_unregister(sec->imgld);
>> +	return 0;
>> +}
>> +
>> +static struct platform_driver intel_m10bmc_secure_driver = {
>> +	.probe = m10bmc_secure_probe,
>> +	.remove = m10bmc_secure_remove,
>> +	.driver = {
>> +		.name = "n3000bmc-secure",
>> +		.dev_groups = m10bmc_sec_attr_groups,
>> +	},
>> +};
>> +module_platform_driver(intel_m10bmc_secure_driver);
>> +
>> +MODULE_ALIAS("platform:n3000bmc-secure");
>> +MODULE_AUTHOR("Intel Corporation");
>> +MODULE_DESCRIPTION("Intel MAX10 BMC Secure Update");
>> +MODULE_LICENSE("GPL v2");
>> -- 
>> 2.25.1

Re: [PATCH v14 4/4] fpga: m10bmc-sec: add max10 secure update functions

[Russ Weight]

On 9/10/21 8:33 AM, Xu Yilun wrote:
> On Thu, Sep 09, 2021 at 04:33:04PM -0700, Russ Weight wrote:
>> Invoke an instance of the FPGA Image Load driver and extend the MAX10
>> BMC Secure Update driver to include the functions that enable secure
>> updates of BMC images, FPGA images, etc.
>>
>> Signed-off-by: Russ Weight <russell.h.weight@intel.com>
>> ---
>> v14:
>>   - Changed symbol names to reflect the renaming of the Security Manager
>>     Class driver to FPGA Image Load.
>> v13:
>>   - No change
>> v12:
>>   - Updated Date and KernelVersion fields in ABI documentation
>>   - Removed size parameter from the write_blk() op. m10bmc_sec_write_blk()
>>     no longer has a size parameter, and the block size is determined
>>     in this (the lower-level) driver.
>> v11:
>>   - No change
>> v10:
>>   - No change
>> v9:
>>   - No change
>> v8:
>>   - Previously patch 5/6, otherwise no change
>> v7:
>>   - No change
>> v6:
>>   - Changed (size / stride) calculation to ((size + stride - 1) / stride)
>>     to ensure that the proper count is passed to regmap_bulk_write().
>>   - Removed unnecessary call to rsu_check_complete() in
>>     m10bmc_sec_poll_complete() and changed while loop to
>>     do/while loop.
>> v5:
>>   - No change
>> v4:
>>   - No change
>> v3:
>>   - Changed: iops -> sops, imgr -> smgr, IFPGA_ -> FPGA_, ifpga_ to fpga_
>>   - Changed "MAX10 BMC Secure Engine driver" to "MAX10 BMC Secure Update
>>     driver"
>>   - Removed wrapper functions (m10bmc_raw_*, m10bmc_sys_*). The
>>     underlying functions are now called directly.
>>   - Changed calling functions of functions that return "enum fpga_sec_err"
>>     to check for (ret != FPGA_SEC_ERR_NONE) instead of (ret)
>> v2:
>>   - Reworked the rsu_start_done() function to make it more readable
>>   - Reworked while-loop condition/content in rsu_prog_ready()
>>   - Minor code cleanup per review comments
>>   - Added a comment to the m10bmc_sec_poll_complete() function to
>>     explain the context (could take 30+ minutes to complete).
>>   - Added m10bmc_ prefix to functions in m10bmc_iops structure
>>   - Moved MAX10 BMC address and function definitions to a separate
>>     patch.
>> ---
>>  drivers/fpga/intel-m10-bmc-secure.c | 310 +++++++++++++++++++++++++++-
>>  1 file changed, 309 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/fpga/intel-m10-bmc-secure.c b/drivers/fpga/intel-m10-bmc-secure.c
>> index ae1383d13bfc..025655684d00 100644
>> --- a/drivers/fpga/intel-m10-bmc-secure.c
>> +++ b/drivers/fpga/intel-m10-bmc-secure.c
>> @@ -181,7 +181,315 @@ static const struct attribute_group *m10bmc_sec_attr_groups[] = {
>>  	NULL,
>>  };
>>  
>> -static const struct fpga_image_load_ops m10bmc_lops = { };
>> +static void log_error_regs(struct m10bmc_sec *sec, u32 doorbell)
>> +{
>> +	u32 auth_result;
>> +
>> +	dev_err(sec->dev, "RSU error status: 0x%08x\n", doorbell);
>> +
>> +	if (!m10bmc_sys_read(sec->m10bmc, M10BMC_AUTH_RESULT, &auth_result))
>> +		dev_err(sec->dev, "RSU auth result: 0x%08x\n", auth_result);
>> +}
>> +
>> +static enum fpga_image_err rsu_check_idle(struct m10bmc_sec *sec)
>> +{
>> +	u32 doorbell;
>> +	int ret;
>> +
>> +	ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
>> +	if (ret)
>> +		return FPGA_IMAGE_ERR_RW_ERROR;
>> +
>> +	if (rsu_prog(doorbell) != RSU_PROG_IDLE &&
>> +	    rsu_prog(doorbell) != RSU_PROG_RSU_DONE) {
>> +		log_error_regs(sec, doorbell);
>> +		return FPGA_IMAGE_ERR_BUSY;
>> +	}
>> +
>> +	return FPGA_IMAGE_ERR_NONE;
>> +}
>> +
>> +static inline bool rsu_start_done(u32 doorbell)
>> +{
>> +	u32 status, progress;
>> +
>> +	if (doorbell & DRBL_RSU_REQUEST)
>> +		return false;
>> +
>> +	status = rsu_stat(doorbell);
>> +	if (status == RSU_STAT_ERASE_FAIL || status == RSU_STAT_WEAROUT)
>> +		return true;
>> +
>> +	progress = rsu_prog(doorbell);
>> +	if (progress != RSU_PROG_IDLE && progress != RSU_PROG_RSU_DONE)
>> +		return true;
>> +
>> +	return false;
>> +}
>> +
>> +static enum fpga_image_err rsu_update_init(struct m10bmc_sec *sec)
>> +{
>> +	u32 doorbell, status;
>> +	int ret;
>> +
>> +	ret = regmap_update_bits(sec->m10bmc->regmap,
>> +				 M10BMC_SYS_BASE + M10BMC_DOORBELL,
>> +				 DRBL_RSU_REQUEST | DRBL_HOST_STATUS,
>> +				 DRBL_RSU_REQUEST |
>> +				 FIELD_PREP(DRBL_HOST_STATUS,
>> +					    HOST_STATUS_IDLE));
>> +	if (ret)
>> +		return FPGA_IMAGE_ERR_RW_ERROR;
>> +
>> +	ret = regmap_read_poll_timeout(sec->m10bmc->regmap,
>> +				       M10BMC_SYS_BASE + M10BMC_DOORBELL,
>> +				       doorbell,
>> +				       rsu_start_done(doorbell),
>> +				       NIOS_HANDSHAKE_INTERVAL_US,
>> +				       NIOS_HANDSHAKE_TIMEOUT_US);
>> +
>> +	if (ret == -ETIMEDOUT) {
>> +		log_error_regs(sec, doorbell);
>> +		return FPGA_IMAGE_ERR_TIMEOUT;
>> +	} else if (ret) {
>> +		return FPGA_IMAGE_ERR_RW_ERROR;
>> +	}
>> +
>> +	status = rsu_stat(doorbell);
>> +	if (status == RSU_STAT_WEAROUT) {
>> +		dev_warn(sec->dev, "Excessive flash update count detected\n");
>> +		return FPGA_IMAGE_ERR_WEAROUT;
>> +	} else if (status == RSU_STAT_ERASE_FAIL) {
>> +		log_error_regs(sec, doorbell);
>> +		return FPGA_IMAGE_ERR_HW_ERROR;
>> +	}
>> +
>> +	return FPGA_IMAGE_ERR_NONE;
>> +}
>> +
>> +static enum fpga_image_err rsu_prog_ready(struct m10bmc_sec *sec)
>> +{
>> +	unsigned long poll_timeout;
>> +	u32 doorbell, progress;
>> +	int ret;
>> +
>> +	ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
>> +	if (ret)
>> +		return FPGA_IMAGE_ERR_RW_ERROR;
>> +
>> +	poll_timeout = jiffies + msecs_to_jiffies(RSU_PREP_TIMEOUT_MS);
>> +	while (rsu_prog(doorbell) == RSU_PROG_PREPARE) {
>> +		msleep(RSU_PREP_INTERVAL_MS);
>> +		if (time_after(jiffies, poll_timeout))
>> +			break;
>> +
>> +		ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
>> +		if (ret)
>> +			return FPGA_IMAGE_ERR_RW_ERROR;
>> +	}
>> +
>> +	progress = rsu_prog(doorbell);
>> +	if (progress == RSU_PROG_PREPARE) {
>> +		log_error_regs(sec, doorbell);
>> +		return FPGA_IMAGE_ERR_TIMEOUT;
>> +	} else if (progress != RSU_PROG_READY) {
>> +		log_error_regs(sec, doorbell);
>> +		return FPGA_IMAGE_ERR_HW_ERROR;
>> +	}
>> +
>> +	return FPGA_IMAGE_ERR_NONE;
>> +}
>> +
>> +static enum fpga_image_err rsu_send_data(struct m10bmc_sec *sec)
>> +{
>> +	u32 doorbell;
>> +	int ret;
>> +
>> +	ret = regmap_update_bits(sec->m10bmc->regmap,
>> +				 M10BMC_SYS_BASE + M10BMC_DOORBELL,
>> +				 DRBL_HOST_STATUS,
>> +				 FIELD_PREP(DRBL_HOST_STATUS,
>> +					    HOST_STATUS_WRITE_DONE));
>> +	if (ret)
>> +		return FPGA_IMAGE_ERR_RW_ERROR;
>> +
>> +	ret = regmap_read_poll_timeout(sec->m10bmc->regmap,
>> +				       M10BMC_SYS_BASE + M10BMC_DOORBELL,
>> +				       doorbell,
>> +				       rsu_prog(doorbell) != RSU_PROG_READY,
>> +				       NIOS_HANDSHAKE_INTERVAL_US,
>> +				       NIOS_HANDSHAKE_TIMEOUT_US);
>> +
>> +	if (ret == -ETIMEDOUT) {
>> +		log_error_regs(sec, doorbell);
>> +		return FPGA_IMAGE_ERR_TIMEOUT;
>> +	} else if (ret) {
>> +		return FPGA_IMAGE_ERR_RW_ERROR;
>> +	}
>> +
>> +	switch (rsu_stat(doorbell)) {
>> +	case RSU_STAT_NORMAL:
>> +	case RSU_STAT_NIOS_OK:
>> +	case RSU_STAT_USER_OK:
>> +	case RSU_STAT_FACTORY_OK:
>> +		break;
>> +	default:
>> +		log_error_regs(sec, doorbell);
>> +		return FPGA_IMAGE_ERR_HW_ERROR;
>> +	}
>> +
>> +	return FPGA_IMAGE_ERR_NONE;
>> +}
>> +
>> +static int rsu_check_complete(struct m10bmc_sec *sec, u32 *doorbell)
>> +{
>> +	if (m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, doorbell))
>> +		return -EIO;
>> +
>> +	switch (rsu_stat(*doorbell)) {
>> +	case RSU_STAT_NORMAL:
>> +	case RSU_STAT_NIOS_OK:
>> +	case RSU_STAT_USER_OK:
>> +	case RSU_STAT_FACTORY_OK:
>> +		break;
>> +	default:
>> +		return -EINVAL;
>> +	}
>> +
>> +	switch (rsu_prog(*doorbell)) {
>> +	case RSU_PROG_IDLE:
>> +	case RSU_PROG_RSU_DONE:
>> +		return 0;
>> +	case RSU_PROG_AUTHENTICATING:
>> +	case RSU_PROG_COPYING:
>> +	case RSU_PROG_UPDATE_CANCEL:
>> +	case RSU_PROG_PROGRAM_KEY_HASH:
>> +		return -EAGAIN;
>> +	default:
>> +		return -EINVAL;
>> +	}
>> +}
>> +
>> +static enum fpga_image_err m10bmc_sec_prepare(struct fpga_image_load *imgld)
>> +{
>> +	struct m10bmc_sec *sec = imgld->priv;
>> +	enum fpga_image_err ret;
>> +
>> +	if (imgld->remaining_size > M10BMC_STAGING_SIZE)
>> +		return FPGA_IMAGE_ERR_INVALID_SIZE;
>> +
>> +	ret = rsu_check_idle(sec);
>> +	if (ret != FPGA_IMAGE_ERR_NONE)
>> +		return ret;
>> +
>> +	ret = rsu_update_init(sec);
>> +	if (ret != FPGA_IMAGE_ERR_NONE)
>> +		return ret;
>> +
>> +	return rsu_prog_ready(sec);
>> +}
>> +
>> +#define WRITE_BLOCK_SIZE 0x4000 /* Update remaining_size every 0x4000 bytes */
>> +
>> +static enum fpga_image_err
>> +m10bmc_sec_write_blk(struct fpga_image_load *imgld, u32 offset)
>> +{
>> +	struct m10bmc_sec *sec = imgld->priv;
>> +	unsigned int stride = regmap_get_reg_stride(sec->m10bmc->regmap);
>> +	u32 doorbell, blk_size;
>> +	int ret;
>> +
>> +	ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
>> +	if (ret) {
>> +		return FPGA_IMAGE_ERR_RW_ERROR;
>> +	} else if (rsu_prog(doorbell) != RSU_PROG_READY) {
>> +		log_error_regs(sec, doorbell);
>> +		return FPGA_IMAGE_ERR_HW_ERROR;
>> +	}
>> +
>> +	blk_size = min_t(u32, imgld->remaining_size, WRITE_BLOCK_SIZE);
>> +	ret = regmap_bulk_write(sec->m10bmc->regmap,
>> +				M10BMC_STAGING_BASE + offset,
>> +				(void *)imgld->data + offset,
>> +				(blk_size + stride - 1) / stride);
>> +
>> +	if (ret)
>> +		return FPGA_IMAGE_ERR_RW_ERROR;
>> +
>> +	imgld->remaining_size -= blk_size;
>> +	return FPGA_IMAGE_ERR_NONE;
>> +}
>> +
>> +/*
>> + * m10bmc_sec_poll_complete() is called after handing things off to
>> + * the BMC firmware. Depending on the type of update, it could be
>> + * 30+ minutes before the BMC firmware completes the update. The
>> + * imgld->driver_unload check allows the driver to be unloaded,
>> + * but the BMC firmware will continue the update and no further
>> + * secure updates can be started for this device until the update
>> + * is complete.
>> + */
>> +static enum fpga_image_err m10bmc_sec_poll_complete(struct fpga_image_load *imgld)
>> +{
>> +	struct m10bmc_sec *sec = imgld->priv;
>> +	unsigned long poll_timeout;
>> +	enum fpga_image_err result;
>> +	u32 doorbell;
>> +	int ret;
>> +
>> +	result = rsu_send_data(sec);
>> +	if (result != FPGA_IMAGE_ERR_NONE)
>> +		return result;
>> +
>> +	poll_timeout = jiffies + msecs_to_jiffies(RSU_COMPLETE_TIMEOUT_MS);
>> +	do {
>> +		msleep(RSU_COMPLETE_INTERVAL_MS);
>> +		ret = rsu_check_complete(sec, &doorbell);
>> +		if (imgld->driver_unload)
>> +			return FPGA_IMAGE_ERR_CANCELED;
> Why we return CANCELED error code to user when driver unload is
> requested?
>
> Users may think the update is failed and the old image is kept,
> but in fact, the update continues and finally the old image is
> replaced by the new one.

I could return FPGA_IMAGE_ERR_NONE, and then userspace code would
think that the update completed without error, even though the
update is still in progress.

Or I could create a new FPGA_IMAGE_ERR_EXIT code to indicate that
the driver has exited while the update is still progressing.

I like the FPGA_IMAGE_ERR_EXIT option best of those two options.
Any other suggestions?

Thanks,
- Russ


>
> Thanks,
> Yilun
>
>> +	} while (ret == -EAGAIN && !time_after(jiffies, poll_timeout));
>> +
>> +	if (ret == -EAGAIN) {
>> +		log_error_regs(sec, doorbell);
>> +		return FPGA_IMAGE_ERR_TIMEOUT;
>> +	} else if (ret == -EIO) {
>> +		return FPGA_IMAGE_ERR_RW_ERROR;
>> +	} else if (ret) {
>> +		log_error_regs(sec, doorbell);
>> +		return FPGA_IMAGE_ERR_HW_ERROR;
>> +	}
>> +
>> +	return FPGA_IMAGE_ERR_NONE;
>> +}
>> +
>> +static enum fpga_image_err m10bmc_sec_cancel(struct fpga_image_load *imgld)
>> +{
>> +	struct m10bmc_sec *sec = imgld->priv;
>> +	u32 doorbell;
>> +	int ret;
>> +
>> +	ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
>> +	if (ret)
>> +		return FPGA_IMAGE_ERR_RW_ERROR;
>> +
>> +	if (rsu_prog(doorbell) != RSU_PROG_READY)
>> +		return FPGA_IMAGE_ERR_BUSY;
>> +
>> +	ret = regmap_update_bits(sec->m10bmc->regmap,
>> +				 M10BMC_SYS_BASE + M10BMC_DOORBELL,
>> +				 DRBL_HOST_STATUS,
>> +				 FIELD_PREP(DRBL_HOST_STATUS,
>> +					    HOST_STATUS_ABORT_RSU));
>> +
>> +	return ret ? FPGA_IMAGE_ERR_RW_ERROR : FPGA_IMAGE_ERR_NONE;
>> +}
>> +
>> +static const struct fpga_image_load_ops m10bmc_lops = {
>> +	.prepare = m10bmc_sec_prepare,
>> +	.write_blk = m10bmc_sec_write_blk,
>> +	.poll_complete = m10bmc_sec_poll_complete,
>> +	.cancel = m10bmc_sec_cancel,
>> +};
>>  
>>  static int m10bmc_secure_probe(struct platform_device *pdev)
>>  {
>> -- 
>> 2.25.1

Re: [PATCH v14 1/4] fpga: m10bmc-sec: create max10 bmc secure update driver

[Tom Rix]

On 9/10/21 1:27 PM, Russ Weight wrote:
>
> On 9/10/21 8:13 AM, Xu Yilun wrote:
>> On Thu, Sep 09, 2021 at 04:33:01PM -0700, Russ Weight wrote:
>>> Create a sub driver for the FPGA Card BMC in order to support secure
>>> updates.  This sub-driver will invoke an instance of the FPGA Image Load
>>> class driver for the image load portion of the update.
>>>
>>> This patch creates the MAX10 BMC Secure Update driver and provides sysfs
>>> files 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@intel.com>
>>> Reviewed-by: Tom Rix <trix@redhat.com>
>>> ---
>>> v14:
>>>    - Changed symbol and text references to reflect the renaming of the
>>>      Security Manager Class driver to FPGA Image Load.
>>> v13:
>>>    - Updated copyright to 2021
>>>    - Updated ABI documentation date and kernel version
>>>    - Call updated fpga_sec_mgr_register() and fpga_sec_mgr_unregister()
>>>      functions instead of devm_fpga_sec_mgr_create() and
>>>      devm_fpga_sec_mgr_register().
>>> v12:
>>>    - Updated Date and KernelVersion fields in ABI documentation
>>> v11:
>>>    - Added Reviewed-by tag
>>> v10:
>>>    - Changed the path expressions in the sysfs documentation to
>>>      replace the n3000 reference with something more generic to
>>>      accomodate other devices that use the same driver.
>>> v9:
>>>    - Rebased to 5.12-rc2 next
>>>    - Updated Date and KernelVersion in ABI documentation
>>> v8:
>>>    - Previously patch 2/6, otherwise no change
>>> v7:
>>>    - Updated Date and KernelVersion in ABI documentation
>>> v6:
>>>    - Added WARN_ON() call for (sha_num_bytes / stride) to assert
>>>      that the proper count is passed to regmap_bulk_read().
>>> v5:
>>>    - No change
>>> v4:
>>>    - Moved sysfs files for displaying the root entry hashes (REH)
>>>      from the FPGA Security Manager class driver to here. The
>>>      m10bmc_reh() and m10bmc_reh_size() functions are removed and
>>>      the functionality from these functions is moved into a
>>>      show_root_entry_hash() function for displaying the REHs.
>>>    - Added ABI documentation for the new sysfs entries:
>>>      sysfs-driver-intel-m10-bmc-secure
>>>    - Updated the MAINTAINERS file to add the new ABI documentation
>>>      file: sysfs-driver-intel-m10-bmc-secure
>>>    - Removed unnecessary ret variable from m10bmc_secure_probe()
>>>    - Incorporated new devm_fpga_sec_mgr_register() function into
>>>      m10bmc_secure_probe() and removed the m10bmc_secure_remove()
>>>      function.
>>> v3:
>>>    - Changed from "Intel FPGA Security Manager" to FPGA Security Manager"
>>>    - Changed: iops -> sops, imgr -> smgr, IFPGA_ -> FPGA_, ifpga_ to fpga_
>>>    - Changed "MAX10 BMC Secure Engine driver" to "MAX10 BMC Secure
>>>      Update driver"
>>>    - Removed wrapper functions (m10bmc_raw_*, m10bmc_sys_*). The
>>>      underlying functions are now called directly.
>>>    - Changed "_root_entry_hash" to "_reh", with a comment explaining
>>>      what reh is.
>>> 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().
>>> ---
>>>   .../testing/sysfs-driver-intel-m10-bmc-secure |  29 ++++
>>>   MAINTAINERS                                   |   2 +
>>>   drivers/fpga/Kconfig                          |  11 ++
>>>   drivers/fpga/Makefile                         |   3 +
>>>   drivers/fpga/intel-m10-bmc-secure.c           | 145 ++++++++++++++++++
>>>   5 files changed, 190 insertions(+)
>>>   create mode 100644 Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
>>>   create mode 100644 drivers/fpga/intel-m10-bmc-secure.c
>>>
>>> diff --git a/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
>>> new file mode 100644
>>> index 000000000000..363403ce992d
>>> --- /dev/null
>>> +++ b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
>>> @@ -0,0 +1,29 @@
>>> +What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/sr_root_entry_hash
>>> +Date:		Aug 2021
>>> +KernelVersion:	5.15
>>> +Contact:	Russ Weight <russell.h.weight@intel.com>
>>> +Description:	Read only. Returns the root entry hash for the static
>>> +		region if one is programmed, else it returns the
>>> +		string: "hash not programmed".  This file is only
>>> +		visible if the underlying device supports it.
>>> +		Format: "0x%x".
>>> +
>>> +What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/pr_root_entry_hash
>>> +Date:		Aug 2021
>>> +KernelVersion:	5.15
>>> +Contact:	Russ Weight <russell.h.weight@intel.com>
>>> +Description:	Read only. Returns the root entry hash for the partial
>>> +		reconfiguration region if one is programmed, else it
>>> +		returns the string: "hash not programmed".  This file
>>> +		is only visible if the underlying device supports it.
>>> +		Format: "0x%x".
>>> +
>>> +What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/bmc_root_entry_hash
>>> +Date:		Aug 2021
>>> +KernelVersion:	5.15
>>> +Contact:	Russ Weight <russell.h.weight@intel.com>
>>> +Description:	Read only. Returns the root entry hash for the BMC image
>>> +		if one is programmed, else it returns the string:
>>> +		"hash not programmed".  This file is only visible if the
>>> +		underlying device supports it.
>>> +		Format: "0x%x".
>>> diff --git a/MAINTAINERS b/MAINTAINERS
>>> index e3fbc1bde9bc..cf93835b4775 100644
>>> --- a/MAINTAINERS
>>> +++ b/MAINTAINERS
>>> @@ -7363,8 +7363,10 @@ M:	Russ Weight <russell.h.weight@intel.com>
>>>   L:	linux-fpga@vger.kernel.org
>>>   S:	Maintained
>>>   F:	Documentation/ABI/testing/sysfs-class-fpga-image-load
>>> +F:	Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
>> Should we change the name of the driver? Some keywords like "image load"
>> or "firmware update" should be in the name.
> I considered that. The image-upload functionality is a subset of  this
> driver. It also exposes security collateral via sysfs, and the image-load
> triggers and power-on-image sysfs files will probably end up in this
> driver too.
>
> The current driver name is intel-m10-bmc-secure. Do we need to keep
> "intel-m10-bmc" in the name?
>
> intel-m10-bmc-sec-fw-update?
> intel-m10-bmc-sec-update?
>
> What do you think? Any other suggestions?

The prefix intel-m10-bmc-sec is clunky and confuses me because I think 
of mfd/intel-m10-bmc.c

How about

dfl-image-load ?

Tom

>
> - Russ
>> Thanks,
>> Yilun
>>
>>>   F:	Documentation/fpga/fpga-image-load.rst
>>>   F:	drivers/fpga/fpga-image-load.c
>>> +F:	drivers/fpga/intel-m10-bmc-secure.c
>>>   F:	include/linux/fpga/fpga-image-load.h
>>>   F:	include/uapi/linux/fpga-image-load.h
>>>   
>>> diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
>>> index c12a14e62fff..9d25b1ec03cd 100644
>>> --- a/drivers/fpga/Kconfig
>>> +++ b/drivers/fpga/Kconfig
>>> @@ -253,4 +253,15 @@ config FPGA_IMAGE_LOAD
>>>   	  and/or the device itself to authenticate and disposition the
>>>   	  image data.
>>>   
>>> +config FPGA_M10_BMC_SECURE
>>> +	tristate "Intel MAX10 BMC Secure Update driver"
>>> +	depends on MFD_INTEL_M10_BMC && FPGA_IMAGE_LOAD
>>> +	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 adf228ee4f5e..8d4c1869ac4c 100644
>>> --- a/drivers/fpga/Makefile
>>> +++ b/drivers/fpga/Makefile
>>> @@ -25,6 +25,9 @@ obj-$(CONFIG_ALTERA_PR_IP_CORE_PLAT)    += altera-pr-ip-core-plat.o
>>>   # FPGA Image Load Framework
>>>   obj-$(CONFIG_FPGA_IMAGE_LOAD)		+= fpga-image-load.o
>>>   
>>> +# FPGA Secure Update Drivers
>>> +obj-$(CONFIG_FPGA_M10_BMC_SECURE)	+= intel-m10-bmc-secure.o
>>> +
>>>   # FPGA Bridge Drivers
>>>   obj-$(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..03fc571f40f2
>>> --- /dev/null
>>> +++ b/drivers/fpga/intel-m10-bmc-secure.c
>>> @@ -0,0 +1,145 @@
>>> +// SPDX-License-Identifier: GPL-2.0
>>> +/*
>>> + * Intel Max10 Board Management Controller Secure Update Driver
>>> + *
>>> + * Copyright (C) 2019-2021 Intel Corporation. All rights reserved.
>>> + *
>>> + */
>>> +#include <linux/bitfield.h>
>>> +#include <linux/device.h>
>>> +#include <linux/fpga/fpga-image-load.h>
>>> +#include <linux/mfd/intel-m10-bmc.h>
>>> +#include <linux/module.h>
>>> +#include <linux/platform_device.h>
>>> +
>>> +struct m10bmc_sec {
>>> +	struct device *dev;
>>> +	struct intel_m10bmc *m10bmc;
>>> +	struct fpga_image_load *imgld;
>>> +};
>>> +
>>> +/* Root Entry Hash (REH) support */
>>> +#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 ssize_t
>>> +show_root_entry_hash(struct device *dev, u32 exp_magic,
>>> +		     u32 prog_addr, u32 reh_addr, char *buf)
>>> +{
>>> +	struct m10bmc_sec *sec = dev_get_drvdata(dev);
>>> +	unsigned int stride = regmap_get_reg_stride(sec->m10bmc->regmap);
>>> +	int sha_num_bytes, i, cnt, ret;
>>> +	u8 hash[REH_SHA384_SIZE];
>>> +	u32 magic;
>>> +
>>> +	ret = m10bmc_raw_read(sec->m10bmc, prog_addr, &magic);
>>> +	if (ret)
>>> +		return ret;
>>> +
>>> +	dev_dbg(dev, "%s magic 0x%08x\n", __func__, magic);
>>> +
>>> +	if (FIELD_GET(REH_MAGIC, magic) != exp_magic)
>>> +		return sysfs_emit(buf, "hash not programmed\n");
>>> +
>>> +	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;
>>> +	}
>>> +
>>> +	WARN_ON(sha_num_bytes % stride);
>>> +	ret = regmap_bulk_read(sec->m10bmc->regmap, reh_addr,
>>> +			       hash, sha_num_bytes / stride);
>>> +	if (ret) {
>>> +		dev_err(dev, "failed to read root entry hash: %x cnt %x: %d\n",
>>> +			reh_addr, sha_num_bytes / stride, ret);
>>> +		return ret;
>>> +	}
>>> +
>>> +	cnt = sprintf(buf, "0x");
>>> +	for (i = 0; i < sha_num_bytes; i++)
>>> +		cnt += sprintf(buf + cnt, "%02x", hash[i]);
>>> +	cnt += sprintf(buf + cnt, "\n");
>>> +
>>> +	return cnt;
>>> +}
>>> +
>>> +#define DEVICE_ATTR_SEC_REH_RO(_name, _magic, _prog_addr, _reh_addr) \
>>> +static ssize_t _name##_root_entry_hash_show(struct device *dev, \
>>> +					    struct device_attribute *attr, \
>>> +					    char *buf) \
>>> +{ return show_root_entry_hash(dev, _magic, _prog_addr, _reh_addr, buf); } \
>>> +static DEVICE_ATTR_RO(_name##_root_entry_hash)
>>> +
>>> +DEVICE_ATTR_SEC_REH_RO(bmc, BMC_PROG_MAGIC, BMC_PROG_ADDR, BMC_REH_ADDR);
>>> +DEVICE_ATTR_SEC_REH_RO(sr, SR_PROG_MAGIC, SR_PROG_ADDR, SR_REH_ADDR);
>>> +DEVICE_ATTR_SEC_REH_RO(pr, PR_PROG_MAGIC, PR_PROG_ADDR, PR_REH_ADDR);
>>> +
>>> +static struct attribute *m10bmc_security_attrs[] = {
>>> +	&dev_attr_bmc_root_entry_hash.attr,
>>> +	&dev_attr_sr_root_entry_hash.attr,
>>> +	&dev_attr_pr_root_entry_hash.attr,
>>> +	NULL,
>>> +};
>>> +
>>> +static struct attribute_group m10bmc_security_attr_group = {
>>> +	.name = "security",
>>> +	.attrs = m10bmc_security_attrs,
>>> +};
>>> +
>>> +static const struct attribute_group *m10bmc_sec_attr_groups[] = {
>>> +	&m10bmc_security_attr_group,
>>> +	NULL,
>>> +};
>>> +
>>> +static const struct fpga_image_load_ops m10bmc_lops = { };
>>> +
>>> +static int m10bmc_secure_probe(struct platform_device *pdev)
>>> +{
>>> +	struct fpga_image_load *imgld;
>>> +	struct m10bmc_sec *sec;
>>> +
>>> +	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);
>>> +
>>> +	imgld = fpga_image_load_register(sec->dev, &m10bmc_lops, sec);
>>> +	if (IS_ERR(imgld)) {
>>> +		dev_err(sec->dev, "FPGA Image Load driver failed to start\n");
>>> +		return PTR_ERR(imgld);
>>> +	}
>>> +
>>> +	sec->imgld = imgld;
>>> +	return 0;
>>> +}
>>> +
>>> +static int m10bmc_secure_remove(struct platform_device *pdev)
>>> +{
>>> +	struct m10bmc_sec *sec = dev_get_drvdata(&pdev->dev);
>>> +
>>> +	fpga_image_load_unregister(sec->imgld);
>>> +	return 0;
>>> +}
>>> +
>>> +static struct platform_driver intel_m10bmc_secure_driver = {
>>> +	.probe = m10bmc_secure_probe,
>>> +	.remove = m10bmc_secure_remove,
>>> +	.driver = {
>>> +		.name = "n3000bmc-secure",
>>> +		.dev_groups = m10bmc_sec_attr_groups,
>>> +	},
>>> +};
>>> +module_platform_driver(intel_m10bmc_secure_driver);
>>> +
>>> +MODULE_ALIAS("platform:n3000bmc-secure");
>>> +MODULE_AUTHOR("Intel Corporation");
>>> +MODULE_DESCRIPTION("Intel MAX10 BMC Secure Update");
>>> +MODULE_LICENSE("GPL v2");
>>> -- 
>>> 2.25.1

Re: [PATCH v14 4/4] fpga: m10bmc-sec: add max10 secure update functions

[Tom Rix]

On 9/10/21 1:40 PM, Russ Weight wrote:
>
> On 9/10/21 8:33 AM, Xu Yilun wrote:
>> On Thu, Sep 09, 2021 at 04:33:04PM -0700, Russ Weight wrote:
>>> Invoke an instance of the FPGA Image Load driver and extend the MAX10
>>> BMC Secure Update driver to include the functions that enable secure
>>> updates of BMC images, FPGA images, etc.
>>>
>>> Signed-off-by: Russ Weight <russell.h.weight@intel.com>
>>> ---
>>> v14:
>>>    - Changed symbol names to reflect the renaming of the Security Manager
>>>      Class driver to FPGA Image Load.
>>> v13:
>>>    - No change
>>> v12:
>>>    - Updated Date and KernelVersion fields in ABI documentation
>>>    - Removed size parameter from the write_blk() op. m10bmc_sec_write_blk()
>>>      no longer has a size parameter, and the block size is determined
>>>      in this (the lower-level) driver.
>>> v11:
>>>    - No change
>>> v10:
>>>    - No change
>>> v9:
>>>    - No change
>>> v8:
>>>    - Previously patch 5/6, otherwise no change
>>> v7:
>>>    - No change
>>> v6:
>>>    - Changed (size / stride) calculation to ((size + stride - 1) / stride)
>>>      to ensure that the proper count is passed to regmap_bulk_write().
>>>    - Removed unnecessary call to rsu_check_complete() in
>>>      m10bmc_sec_poll_complete() and changed while loop to
>>>      do/while loop.
>>> v5:
>>>    - No change
>>> v4:
>>>    - No change
>>> v3:
>>>    - Changed: iops -> sops, imgr -> smgr, IFPGA_ -> FPGA_, ifpga_ to fpga_
>>>    - Changed "MAX10 BMC Secure Engine driver" to "MAX10 BMC Secure Update
>>>      driver"
>>>    - Removed wrapper functions (m10bmc_raw_*, m10bmc_sys_*). The
>>>      underlying functions are now called directly.
>>>    - Changed calling functions of functions that return "enum fpga_sec_err"
>>>      to check for (ret != FPGA_SEC_ERR_NONE) instead of (ret)
>>> v2:
>>>    - Reworked the rsu_start_done() function to make it more readable
>>>    - Reworked while-loop condition/content in rsu_prog_ready()
>>>    - Minor code cleanup per review comments
>>>    - Added a comment to the m10bmc_sec_poll_complete() function to
>>>      explain the context (could take 30+ minutes to complete).
>>>    - Added m10bmc_ prefix to functions in m10bmc_iops structure
>>>    - Moved MAX10 BMC address and function definitions to a separate
>>>      patch.
>>> ---
>>>   drivers/fpga/intel-m10-bmc-secure.c | 310 +++++++++++++++++++++++++++-
>>>   1 file changed, 309 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/fpga/intel-m10-bmc-secure.c b/drivers/fpga/intel-m10-bmc-secure.c
>>> index ae1383d13bfc..025655684d00 100644
>>> --- a/drivers/fpga/intel-m10-bmc-secure.c
>>> +++ b/drivers/fpga/intel-m10-bmc-secure.c
>>> @@ -181,7 +181,315 @@ static const struct attribute_group *m10bmc_sec_attr_groups[] = {
>>>   	NULL,
>>>   };
>>>   
>>> -static const struct fpga_image_load_ops m10bmc_lops = { };
>>> +static void log_error_regs(struct m10bmc_sec *sec, u32 doorbell)
>>> +{
>>> +	u32 auth_result;
>>> +
>>> +	dev_err(sec->dev, "RSU error status: 0x%08x\n", doorbell);
>>> +
>>> +	if (!m10bmc_sys_read(sec->m10bmc, M10BMC_AUTH_RESULT, &auth_result))
>>> +		dev_err(sec->dev, "RSU auth result: 0x%08x\n", auth_result);
>>> +}
>>> +
>>> +static enum fpga_image_err rsu_check_idle(struct m10bmc_sec *sec)
>>> +{
>>> +	u32 doorbell;
>>> +	int ret;
>>> +
>>> +	ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
>>> +	if (ret)
>>> +		return FPGA_IMAGE_ERR_RW_ERROR;
>>> +
>>> +	if (rsu_prog(doorbell) != RSU_PROG_IDLE &&
>>> +	    rsu_prog(doorbell) != RSU_PROG_RSU_DONE) {
>>> +		log_error_regs(sec, doorbell);
>>> +		return FPGA_IMAGE_ERR_BUSY;
>>> +	}
>>> +
>>> +	return FPGA_IMAGE_ERR_NONE;
>>> +}
>>> +
>>> +static inline bool rsu_start_done(u32 doorbell)
>>> +{
>>> +	u32 status, progress;
>>> +
>>> +	if (doorbell & DRBL_RSU_REQUEST)
>>> +		return false;
>>> +
>>> +	status = rsu_stat(doorbell);
>>> +	if (status == RSU_STAT_ERASE_FAIL || status == RSU_STAT_WEAROUT)
>>> +		return true;
>>> +
>>> +	progress = rsu_prog(doorbell);
>>> +	if (progress != RSU_PROG_IDLE && progress != RSU_PROG_RSU_DONE)
>>> +		return true;
>>> +
>>> +	return false;
>>> +}
>>> +
>>> +static enum fpga_image_err rsu_update_init(struct m10bmc_sec *sec)
>>> +{
>>> +	u32 doorbell, status;
>>> +	int ret;
>>> +
>>> +	ret = regmap_update_bits(sec->m10bmc->regmap,
>>> +				 M10BMC_SYS_BASE + M10BMC_DOORBELL,
>>> +				 DRBL_RSU_REQUEST | DRBL_HOST_STATUS,
>>> +				 DRBL_RSU_REQUEST |
>>> +				 FIELD_PREP(DRBL_HOST_STATUS,
>>> +					    HOST_STATUS_IDLE));
>>> +	if (ret)
>>> +		return FPGA_IMAGE_ERR_RW_ERROR;
>>> +
>>> +	ret = regmap_read_poll_timeout(sec->m10bmc->regmap,
>>> +				       M10BMC_SYS_BASE + M10BMC_DOORBELL,
>>> +				       doorbell,
>>> +				       rsu_start_done(doorbell),
>>> +				       NIOS_HANDSHAKE_INTERVAL_US,
>>> +				       NIOS_HANDSHAKE_TIMEOUT_US);
>>> +
>>> +	if (ret == -ETIMEDOUT) {
>>> +		log_error_regs(sec, doorbell);
>>> +		return FPGA_IMAGE_ERR_TIMEOUT;
>>> +	} else if (ret) {
>>> +		return FPGA_IMAGE_ERR_RW_ERROR;
>>> +	}
>>> +
>>> +	status = rsu_stat(doorbell);
>>> +	if (status == RSU_STAT_WEAROUT) {
>>> +		dev_warn(sec->dev, "Excessive flash update count detected\n");
>>> +		return FPGA_IMAGE_ERR_WEAROUT;
>>> +	} else if (status == RSU_STAT_ERASE_FAIL) {
>>> +		log_error_regs(sec, doorbell);
>>> +		return FPGA_IMAGE_ERR_HW_ERROR;
>>> +	}
>>> +
>>> +	return FPGA_IMAGE_ERR_NONE;
>>> +}
>>> +
>>> +static enum fpga_image_err rsu_prog_ready(struct m10bmc_sec *sec)
>>> +{
>>> +	unsigned long poll_timeout;
>>> +	u32 doorbell, progress;
>>> +	int ret;
>>> +
>>> +	ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
>>> +	if (ret)
>>> +		return FPGA_IMAGE_ERR_RW_ERROR;
>>> +
>>> +	poll_timeout = jiffies + msecs_to_jiffies(RSU_PREP_TIMEOUT_MS);
>>> +	while (rsu_prog(doorbell) == RSU_PROG_PREPARE) {
>>> +		msleep(RSU_PREP_INTERVAL_MS);
>>> +		if (time_after(jiffies, poll_timeout))
>>> +			break;
>>> +
>>> +		ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
>>> +		if (ret)
>>> +			return FPGA_IMAGE_ERR_RW_ERROR;
>>> +	}
>>> +
>>> +	progress = rsu_prog(doorbell);
>>> +	if (progress == RSU_PROG_PREPARE) {
>>> +		log_error_regs(sec, doorbell);
>>> +		return FPGA_IMAGE_ERR_TIMEOUT;
>>> +	} else if (progress != RSU_PROG_READY) {
>>> +		log_error_regs(sec, doorbell);
>>> +		return FPGA_IMAGE_ERR_HW_ERROR;
>>> +	}
>>> +
>>> +	return FPGA_IMAGE_ERR_NONE;
>>> +}
>>> +
>>> +static enum fpga_image_err rsu_send_data(struct m10bmc_sec *sec)
>>> +{
>>> +	u32 doorbell;
>>> +	int ret;
>>> +
>>> +	ret = regmap_update_bits(sec->m10bmc->regmap,
>>> +				 M10BMC_SYS_BASE + M10BMC_DOORBELL,
>>> +				 DRBL_HOST_STATUS,
>>> +				 FIELD_PREP(DRBL_HOST_STATUS,
>>> +					    HOST_STATUS_WRITE_DONE));
>>> +	if (ret)
>>> +		return FPGA_IMAGE_ERR_RW_ERROR;
>>> +
>>> +	ret = regmap_read_poll_timeout(sec->m10bmc->regmap,
>>> +				       M10BMC_SYS_BASE + M10BMC_DOORBELL,
>>> +				       doorbell,
>>> +				       rsu_prog(doorbell) != RSU_PROG_READY,
>>> +				       NIOS_HANDSHAKE_INTERVAL_US,
>>> +				       NIOS_HANDSHAKE_TIMEOUT_US);
>>> +
>>> +	if (ret == -ETIMEDOUT) {
>>> +		log_error_regs(sec, doorbell);
>>> +		return FPGA_IMAGE_ERR_TIMEOUT;
>>> +	} else if (ret) {
>>> +		return FPGA_IMAGE_ERR_RW_ERROR;
>>> +	}
>>> +
>>> +	switch (rsu_stat(doorbell)) {
>>> +	case RSU_STAT_NORMAL:
>>> +	case RSU_STAT_NIOS_OK:
>>> +	case RSU_STAT_USER_OK:
>>> +	case RSU_STAT_FACTORY_OK:
>>> +		break;
>>> +	default:
>>> +		log_error_regs(sec, doorbell);
>>> +		return FPGA_IMAGE_ERR_HW_ERROR;
>>> +	}
>>> +
>>> +	return FPGA_IMAGE_ERR_NONE;
>>> +}
>>> +
>>> +static int rsu_check_complete(struct m10bmc_sec *sec, u32 *doorbell)
>>> +{
>>> +	if (m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, doorbell))
>>> +		return -EIO;
>>> +
>>> +	switch (rsu_stat(*doorbell)) {
>>> +	case RSU_STAT_NORMAL:
>>> +	case RSU_STAT_NIOS_OK:
>>> +	case RSU_STAT_USER_OK:
>>> +	case RSU_STAT_FACTORY_OK:
>>> +		break;
>>> +	default:
>>> +		return -EINVAL;
>>> +	}
>>> +
>>> +	switch (rsu_prog(*doorbell)) {
>>> +	case RSU_PROG_IDLE:
>>> +	case RSU_PROG_RSU_DONE:
>>> +		return 0;
>>> +	case RSU_PROG_AUTHENTICATING:
>>> +	case RSU_PROG_COPYING:
>>> +	case RSU_PROG_UPDATE_CANCEL:
>>> +	case RSU_PROG_PROGRAM_KEY_HASH:
>>> +		return -EAGAIN;
>>> +	default:
>>> +		return -EINVAL;
>>> +	}
>>> +}
>>> +
>>> +static enum fpga_image_err m10bmc_sec_prepare(struct fpga_image_load *imgld)
>>> +{
>>> +	struct m10bmc_sec *sec = imgld->priv;
>>> +	enum fpga_image_err ret;
>>> +
>>> +	if (imgld->remaining_size > M10BMC_STAGING_SIZE)
>>> +		return FPGA_IMAGE_ERR_INVALID_SIZE;
>>> +
>>> +	ret = rsu_check_idle(sec);
>>> +	if (ret != FPGA_IMAGE_ERR_NONE)
>>> +		return ret;
>>> +
>>> +	ret = rsu_update_init(sec);
>>> +	if (ret != FPGA_IMAGE_ERR_NONE)
>>> +		return ret;
>>> +
>>> +	return rsu_prog_ready(sec);
>>> +}
>>> +
>>> +#define WRITE_BLOCK_SIZE 0x4000 /* Update remaining_size every 0x4000 bytes */
>>> +
>>> +static enum fpga_image_err
>>> +m10bmc_sec_write_blk(struct fpga_image_load *imgld, u32 offset)
>>> +{
>>> +	struct m10bmc_sec *sec = imgld->priv;
>>> +	unsigned int stride = regmap_get_reg_stride(sec->m10bmc->regmap);
>>> +	u32 doorbell, blk_size;
>>> +	int ret;
>>> +
>>> +	ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
>>> +	if (ret) {
>>> +		return FPGA_IMAGE_ERR_RW_ERROR;
>>> +	} else if (rsu_prog(doorbell) != RSU_PROG_READY) {
>>> +		log_error_regs(sec, doorbell);
>>> +		return FPGA_IMAGE_ERR_HW_ERROR;
>>> +	}
>>> +
>>> +	blk_size = min_t(u32, imgld->remaining_size, WRITE_BLOCK_SIZE);
>>> +	ret = regmap_bulk_write(sec->m10bmc->regmap,
>>> +				M10BMC_STAGING_BASE + offset,
>>> +				(void *)imgld->data + offset,
>>> +				(blk_size + stride - 1) / stride);
>>> +
>>> +	if (ret)
>>> +		return FPGA_IMAGE_ERR_RW_ERROR;
>>> +
>>> +	imgld->remaining_size -= blk_size;
>>> +	return FPGA_IMAGE_ERR_NONE;
>>> +}
>>> +
>>> +/*
>>> + * m10bmc_sec_poll_complete() is called after handing things off to
>>> + * the BMC firmware. Depending on the type of update, it could be
>>> + * 30+ minutes before the BMC firmware completes the update. The
>>> + * imgld->driver_unload check allows the driver to be unloaded,
>>> + * but the BMC firmware will continue the update and no further
>>> + * secure updates can be started for this device until the update
>>> + * is complete.
>>> + */
>>> +static enum fpga_image_err m10bmc_sec_poll_complete(struct fpga_image_load *imgld)
>>> +{
>>> +	struct m10bmc_sec *sec = imgld->priv;
>>> +	unsigned long poll_timeout;
>>> +	enum fpga_image_err result;
>>> +	u32 doorbell;
>>> +	int ret;
>>> +
>>> +	result = rsu_send_data(sec);
>>> +	if (result != FPGA_IMAGE_ERR_NONE)
>>> +		return result;
>>> +
>>> +	poll_timeout = jiffies + msecs_to_jiffies(RSU_COMPLETE_TIMEOUT_MS);
>>> +	do {
>>> +		msleep(RSU_COMPLETE_INTERVAL_MS);
>>> +		ret = rsu_check_complete(sec, &doorbell);
>>> +		if (imgld->driver_unload)
>>> +			return FPGA_IMAGE_ERR_CANCELED;
>> Why we return CANCELED error code to user when driver unload is
>> requested?
>>
>> Users may think the update is failed and the old image is kept,
>> but in fact, the update continues and finally the old image is
>> replaced by the new one.
> I could return FPGA_IMAGE_ERR_NONE, and then userspace code would
> think that the update completed without error, even though the
> update is still in progress.
>
> Or I could create a new FPGA_IMAGE_ERR_EXIT code to indicate that
> the driver has exited while the update is still progressing.
>
> I like the FPGA_IMAGE_ERR_EXIT option best of those two options.
> Any other suggestions?

No device so, -ENODEV

Tom

>
> Thanks,
> - Russ
>
>
>> Thanks,
>> Yilun
>>
>>> +	} while (ret == -EAGAIN && !time_after(jiffies, poll_timeout));
>>> +
>>> +	if (ret == -EAGAIN) {
>>> +		log_error_regs(sec, doorbell);
>>> +		return FPGA_IMAGE_ERR_TIMEOUT;
>>> +	} else if (ret == -EIO) {
>>> +		return FPGA_IMAGE_ERR_RW_ERROR;
>>> +	} else if (ret) {
>>> +		log_error_regs(sec, doorbell);
>>> +		return FPGA_IMAGE_ERR_HW_ERROR;
>>> +	}
>>> +
>>> +	return FPGA_IMAGE_ERR_NONE;
>>> +}
>>> +
>>> +static enum fpga_image_err m10bmc_sec_cancel(struct fpga_image_load *imgld)
>>> +{
>>> +	struct m10bmc_sec *sec = imgld->priv;
>>> +	u32 doorbell;
>>> +	int ret;
>>> +
>>> +	ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
>>> +	if (ret)
>>> +		return FPGA_IMAGE_ERR_RW_ERROR;
>>> +
>>> +	if (rsu_prog(doorbell) != RSU_PROG_READY)
>>> +		return FPGA_IMAGE_ERR_BUSY;
>>> +
>>> +	ret = regmap_update_bits(sec->m10bmc->regmap,
>>> +				 M10BMC_SYS_BASE + M10BMC_DOORBELL,
>>> +				 DRBL_HOST_STATUS,
>>> +				 FIELD_PREP(DRBL_HOST_STATUS,
>>> +					    HOST_STATUS_ABORT_RSU));
>>> +
>>> +	return ret ? FPGA_IMAGE_ERR_RW_ERROR : FPGA_IMAGE_ERR_NONE;
>>> +}
>>> +
>>> +static const struct fpga_image_load_ops m10bmc_lops = {
>>> +	.prepare = m10bmc_sec_prepare,
>>> +	.write_blk = m10bmc_sec_write_blk,
>>> +	.poll_complete = m10bmc_sec_poll_complete,
>>> +	.cancel = m10bmc_sec_cancel,
>>> +};
>>>   
>>>   static int m10bmc_secure_probe(struct platform_device *pdev)
>>>   {
>>> -- 
>>> 2.25.1

Re: [PATCH v14 1/4] fpga: m10bmc-sec: create max10 bmc secure update driver

[Xu Yilun]

On Sat, Sep 11, 2021 at 12:04:07PM -0700, Tom Rix wrote:
> 
> On 9/10/21 1:27 PM, Russ Weight wrote:
> > 
> > On 9/10/21 8:13 AM, Xu Yilun wrote:
> > > On Thu, Sep 09, 2021 at 04:33:01PM -0700, Russ Weight wrote:
> > > > Create a sub driver for the FPGA Card BMC in order to support secure
> > > > updates.  This sub-driver will invoke an instance of the FPGA Image Load
> > > > class driver for the image load portion of the update.
> > > > 
> > > > This patch creates the MAX10 BMC Secure Update driver and provides sysfs
> > > > files 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@intel.com>
> > > > Reviewed-by: Tom Rix <trix@redhat.com>
> > > > ---
> > > > v14:
> > > >    - Changed symbol and text references to reflect the renaming of the
> > > >      Security Manager Class driver to FPGA Image Load.
> > > > v13:
> > > >    - Updated copyright to 2021
> > > >    - Updated ABI documentation date and kernel version
> > > >    - Call updated fpga_sec_mgr_register() and fpga_sec_mgr_unregister()
> > > >      functions instead of devm_fpga_sec_mgr_create() and
> > > >      devm_fpga_sec_mgr_register().
> > > > v12:
> > > >    - Updated Date and KernelVersion fields in ABI documentation
> > > > v11:
> > > >    - Added Reviewed-by tag
> > > > v10:
> > > >    - Changed the path expressions in the sysfs documentation to
> > > >      replace the n3000 reference with something more generic to
> > > >      accomodate other devices that use the same driver.
> > > > v9:
> > > >    - Rebased to 5.12-rc2 next
> > > >    - Updated Date and KernelVersion in ABI documentation
> > > > v8:
> > > >    - Previously patch 2/6, otherwise no change
> > > > v7:
> > > >    - Updated Date and KernelVersion in ABI documentation
> > > > v6:
> > > >    - Added WARN_ON() call for (sha_num_bytes / stride) to assert
> > > >      that the proper count is passed to regmap_bulk_read().
> > > > v5:
> > > >    - No change
> > > > v4:
> > > >    - Moved sysfs files for displaying the root entry hashes (REH)
> > > >      from the FPGA Security Manager class driver to here. The
> > > >      m10bmc_reh() and m10bmc_reh_size() functions are removed and
> > > >      the functionality from these functions is moved into a
> > > >      show_root_entry_hash() function for displaying the REHs.
> > > >    - Added ABI documentation for the new sysfs entries:
> > > >      sysfs-driver-intel-m10-bmc-secure
> > > >    - Updated the MAINTAINERS file to add the new ABI documentation
> > > >      file: sysfs-driver-intel-m10-bmc-secure
> > > >    - Removed unnecessary ret variable from m10bmc_secure_probe()
> > > >    - Incorporated new devm_fpga_sec_mgr_register() function into
> > > >      m10bmc_secure_probe() and removed the m10bmc_secure_remove()
> > > >      function.
> > > > v3:
> > > >    - Changed from "Intel FPGA Security Manager" to FPGA Security Manager"
> > > >    - Changed: iops -> sops, imgr -> smgr, IFPGA_ -> FPGA_, ifpga_ to fpga_
> > > >    - Changed "MAX10 BMC Secure Engine driver" to "MAX10 BMC Secure
> > > >      Update driver"
> > > >    - Removed wrapper functions (m10bmc_raw_*, m10bmc_sys_*). The
> > > >      underlying functions are now called directly.
> > > >    - Changed "_root_entry_hash" to "_reh", with a comment explaining
> > > >      what reh is.
> > > > 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().
> > > > ---
> > > >   .../testing/sysfs-driver-intel-m10-bmc-secure |  29 ++++
> > > >   MAINTAINERS                                   |   2 +
> > > >   drivers/fpga/Kconfig                          |  11 ++
> > > >   drivers/fpga/Makefile                         |   3 +
> > > >   drivers/fpga/intel-m10-bmc-secure.c           | 145 ++++++++++++++++++
> > > >   5 files changed, 190 insertions(+)
> > > >   create mode 100644 Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
> > > >   create mode 100644 drivers/fpga/intel-m10-bmc-secure.c
> > > > 
> > > > diff --git a/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
> > > > new file mode 100644
> > > > index 000000000000..363403ce992d
> > > > --- /dev/null
> > > > +++ b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
> > > > @@ -0,0 +1,29 @@
> > > > +What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/sr_root_entry_hash
> > > > +Date:		Aug 2021
> > > > +KernelVersion:	5.15
> > > > +Contact:	Russ Weight <russell.h.weight@intel.com>
> > > > +Description:	Read only. Returns the root entry hash for the static
> > > > +		region if one is programmed, else it returns the
> > > > +		string: "hash not programmed".  This file is only
> > > > +		visible if the underlying device supports it.
> > > > +		Format: "0x%x".
> > > > +
> > > > +What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/pr_root_entry_hash
> > > > +Date:		Aug 2021
> > > > +KernelVersion:	5.15
> > > > +Contact:	Russ Weight <russell.h.weight@intel.com>
> > > > +Description:	Read only. Returns the root entry hash for the partial
> > > > +		reconfiguration region if one is programmed, else it
> > > > +		returns the string: "hash not programmed".  This file
> > > > +		is only visible if the underlying device supports it.
> > > > +		Format: "0x%x".
> > > > +
> > > > +What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/bmc_root_entry_hash
> > > > +Date:		Aug 2021
> > > > +KernelVersion:	5.15
> > > > +Contact:	Russ Weight <russell.h.weight@intel.com>
> > > > +Description:	Read only. Returns the root entry hash for the BMC image
> > > > +		if one is programmed, else it returns the string:
> > > > +		"hash not programmed".  This file is only visible if the
> > > > +		underlying device supports it.
> > > > +		Format: "0x%x".
> > > > diff --git a/MAINTAINERS b/MAINTAINERS
> > > > index e3fbc1bde9bc..cf93835b4775 100644
> > > > --- a/MAINTAINERS
> > > > +++ b/MAINTAINERS
> > > > @@ -7363,8 +7363,10 @@ M:	Russ Weight <russell.h.weight@intel.com>
> > > >   L:	linux-fpga@vger.kernel.org
> > > >   S:	Maintained
> > > >   F:	Documentation/ABI/testing/sysfs-class-fpga-image-load
> > > > +F:	Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
> > > Should we change the name of the driver? Some keywords like "image load"
> > > or "firmware update" should be in the name.
> > I considered that. The image-upload functionality is a subset of  this
> > driver. It also exposes security collateral via sysfs, and the image-load
> > triggers and power-on-image sysfs files will probably end up in this
> > driver too.
> > 
> > The current driver name is intel-m10-bmc-secure. Do we need to keep
> > "intel-m10-bmc" in the name?
> > 
> > intel-m10-bmc-sec-fw-update?
> > intel-m10-bmc-sec-update?
> > 
> > What do you think? Any other suggestions?

The single word "secure" is quite indistinct to me. I think
intel-m10-bmc-sec-update is much better.

> 
> The prefix intel-m10-bmc-sec is clunky and confuses me because I think of
> mfd/intel-m10-bmc.c

The secure update engine is now implemented in MAX10 bmc. The driver
code also assumes it is always a sub device of MAX10 bmc. So my
preference is we keep the prefix.

> 
> How about
> 
> dfl-image-load ?

There may be several secure update engines for DFL based FPGAs. So we
may be more specific.

Thanks,
Yilun

Re: [PATCH v14 4/4] fpga: m10bmc-sec: add max10 secure update functions

[Xu Yilun]

On Fri, Sep 10, 2021 at 01:40:43PM -0700, Russ Weight wrote:
> 
> 
> On 9/10/21 8:33 AM, Xu Yilun wrote:
> > On Thu, Sep 09, 2021 at 04:33:04PM -0700, Russ Weight wrote:
> >> Invoke an instance of the FPGA Image Load driver and extend the MAX10
> >> BMC Secure Update driver to include the functions that enable secure
> >> updates of BMC images, FPGA images, etc.
> >>
> >> Signed-off-by: Russ Weight <russell.h.weight@intel.com>
> >> ---
> >> v14:
> >>   - Changed symbol names to reflect the renaming of the Security Manager
> >>     Class driver to FPGA Image Load.
> >> v13:
> >>   - No change
> >> v12:
> >>   - Updated Date and KernelVersion fields in ABI documentation
> >>   - Removed size parameter from the write_blk() op. m10bmc_sec_write_blk()
> >>     no longer has a size parameter, and the block size is determined
> >>     in this (the lower-level) driver.
> >> v11:
> >>   - No change
> >> v10:
> >>   - No change
> >> v9:
> >>   - No change
> >> v8:
> >>   - Previously patch 5/6, otherwise no change
> >> v7:
> >>   - No change
> >> v6:
> >>   - Changed (size / stride) calculation to ((size + stride - 1) / stride)
> >>     to ensure that the proper count is passed to regmap_bulk_write().
> >>   - Removed unnecessary call to rsu_check_complete() in
> >>     m10bmc_sec_poll_complete() and changed while loop to
> >>     do/while loop.
> >> v5:
> >>   - No change
> >> v4:
> >>   - No change
> >> v3:
> >>   - Changed: iops -> sops, imgr -> smgr, IFPGA_ -> FPGA_, ifpga_ to fpga_
> >>   - Changed "MAX10 BMC Secure Engine driver" to "MAX10 BMC Secure Update
> >>     driver"
> >>   - Removed wrapper functions (m10bmc_raw_*, m10bmc_sys_*). The
> >>     underlying functions are now called directly.
> >>   - Changed calling functions of functions that return "enum fpga_sec_err"
> >>     to check for (ret != FPGA_SEC_ERR_NONE) instead of (ret)
> >> v2:
> >>   - Reworked the rsu_start_done() function to make it more readable
> >>   - Reworked while-loop condition/content in rsu_prog_ready()
> >>   - Minor code cleanup per review comments
> >>   - Added a comment to the m10bmc_sec_poll_complete() function to
> >>     explain the context (could take 30+ minutes to complete).
> >>   - Added m10bmc_ prefix to functions in m10bmc_iops structure
> >>   - Moved MAX10 BMC address and function definitions to a separate
> >>     patch.
> >> ---
> >>  drivers/fpga/intel-m10-bmc-secure.c | 310 +++++++++++++++++++++++++++-
> >>  1 file changed, 309 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/fpga/intel-m10-bmc-secure.c b/drivers/fpga/intel-m10-bmc-secure.c
> >> index ae1383d13bfc..025655684d00 100644
> >> --- a/drivers/fpga/intel-m10-bmc-secure.c
> >> +++ b/drivers/fpga/intel-m10-bmc-secure.c
> >> @@ -181,7 +181,315 @@ static const struct attribute_group *m10bmc_sec_attr_groups[] = {
> >>  	NULL,
> >>  };
> >>  
> >> -static const struct fpga_image_load_ops m10bmc_lops = { };
> >> +static void log_error_regs(struct m10bmc_sec *sec, u32 doorbell)
> >> +{
> >> +	u32 auth_result;
> >> +
> >> +	dev_err(sec->dev, "RSU error status: 0x%08x\n", doorbell);
> >> +
> >> +	if (!m10bmc_sys_read(sec->m10bmc, M10BMC_AUTH_RESULT, &auth_result))
> >> +		dev_err(sec->dev, "RSU auth result: 0x%08x\n", auth_result);
> >> +}
> >> +
> >> +static enum fpga_image_err rsu_check_idle(struct m10bmc_sec *sec)
> >> +{
> >> +	u32 doorbell;
> >> +	int ret;
> >> +
> >> +	ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
> >> +	if (ret)
> >> +		return FPGA_IMAGE_ERR_RW_ERROR;
> >> +
> >> +	if (rsu_prog(doorbell) != RSU_PROG_IDLE &&
> >> +	    rsu_prog(doorbell) != RSU_PROG_RSU_DONE) {
> >> +		log_error_regs(sec, doorbell);
> >> +		return FPGA_IMAGE_ERR_BUSY;
> >> +	}
> >> +
> >> +	return FPGA_IMAGE_ERR_NONE;
> >> +}
> >> +
> >> +static inline bool rsu_start_done(u32 doorbell)
> >> +{
> >> +	u32 status, progress;
> >> +
> >> +	if (doorbell & DRBL_RSU_REQUEST)
> >> +		return false;
> >> +
> >> +	status = rsu_stat(doorbell);
> >> +	if (status == RSU_STAT_ERASE_FAIL || status == RSU_STAT_WEAROUT)
> >> +		return true;
> >> +
> >> +	progress = rsu_prog(doorbell);
> >> +	if (progress != RSU_PROG_IDLE && progress != RSU_PROG_RSU_DONE)
> >> +		return true;
> >> +
> >> +	return false;
> >> +}
> >> +
> >> +static enum fpga_image_err rsu_update_init(struct m10bmc_sec *sec)
> >> +{
> >> +	u32 doorbell, status;
> >> +	int ret;
> >> +
> >> +	ret = regmap_update_bits(sec->m10bmc->regmap,
> >> +				 M10BMC_SYS_BASE + M10BMC_DOORBELL,
> >> +				 DRBL_RSU_REQUEST | DRBL_HOST_STATUS,
> >> +				 DRBL_RSU_REQUEST |
> >> +				 FIELD_PREP(DRBL_HOST_STATUS,
> >> +					    HOST_STATUS_IDLE));
> >> +	if (ret)
> >> +		return FPGA_IMAGE_ERR_RW_ERROR;
> >> +
> >> +	ret = regmap_read_poll_timeout(sec->m10bmc->regmap,
> >> +				       M10BMC_SYS_BASE + M10BMC_DOORBELL,
> >> +				       doorbell,
> >> +				       rsu_start_done(doorbell),
> >> +				       NIOS_HANDSHAKE_INTERVAL_US,
> >> +				       NIOS_HANDSHAKE_TIMEOUT_US);
> >> +
> >> +	if (ret == -ETIMEDOUT) {
> >> +		log_error_regs(sec, doorbell);
> >> +		return FPGA_IMAGE_ERR_TIMEOUT;
> >> +	} else if (ret) {
> >> +		return FPGA_IMAGE_ERR_RW_ERROR;
> >> +	}
> >> +
> >> +	status = rsu_stat(doorbell);
> >> +	if (status == RSU_STAT_WEAROUT) {
> >> +		dev_warn(sec->dev, "Excessive flash update count detected\n");
> >> +		return FPGA_IMAGE_ERR_WEAROUT;
> >> +	} else if (status == RSU_STAT_ERASE_FAIL) {
> >> +		log_error_regs(sec, doorbell);
> >> +		return FPGA_IMAGE_ERR_HW_ERROR;
> >> +	}
> >> +
> >> +	return FPGA_IMAGE_ERR_NONE;
> >> +}
> >> +
> >> +static enum fpga_image_err rsu_prog_ready(struct m10bmc_sec *sec)
> >> +{
> >> +	unsigned long poll_timeout;
> >> +	u32 doorbell, progress;
> >> +	int ret;
> >> +
> >> +	ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
> >> +	if (ret)
> >> +		return FPGA_IMAGE_ERR_RW_ERROR;
> >> +
> >> +	poll_timeout = jiffies + msecs_to_jiffies(RSU_PREP_TIMEOUT_MS);
> >> +	while (rsu_prog(doorbell) == RSU_PROG_PREPARE) {
> >> +		msleep(RSU_PREP_INTERVAL_MS);
> >> +		if (time_after(jiffies, poll_timeout))
> >> +			break;
> >> +
> >> +		ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
> >> +		if (ret)
> >> +			return FPGA_IMAGE_ERR_RW_ERROR;
> >> +	}
> >> +
> >> +	progress = rsu_prog(doorbell);
> >> +	if (progress == RSU_PROG_PREPARE) {
> >> +		log_error_regs(sec, doorbell);
> >> +		return FPGA_IMAGE_ERR_TIMEOUT;
> >> +	} else if (progress != RSU_PROG_READY) {
> >> +		log_error_regs(sec, doorbell);
> >> +		return FPGA_IMAGE_ERR_HW_ERROR;
> >> +	}
> >> +
> >> +	return FPGA_IMAGE_ERR_NONE;
> >> +}
> >> +
> >> +static enum fpga_image_err rsu_send_data(struct m10bmc_sec *sec)
> >> +{
> >> +	u32 doorbell;
> >> +	int ret;
> >> +
> >> +	ret = regmap_update_bits(sec->m10bmc->regmap,
> >> +				 M10BMC_SYS_BASE + M10BMC_DOORBELL,
> >> +				 DRBL_HOST_STATUS,
> >> +				 FIELD_PREP(DRBL_HOST_STATUS,
> >> +					    HOST_STATUS_WRITE_DONE));
> >> +	if (ret)
> >> +		return FPGA_IMAGE_ERR_RW_ERROR;
> >> +
> >> +	ret = regmap_read_poll_timeout(sec->m10bmc->regmap,
> >> +				       M10BMC_SYS_BASE + M10BMC_DOORBELL,
> >> +				       doorbell,
> >> +				       rsu_prog(doorbell) != RSU_PROG_READY,
> >> +				       NIOS_HANDSHAKE_INTERVAL_US,
> >> +				       NIOS_HANDSHAKE_TIMEOUT_US);
> >> +
> >> +	if (ret == -ETIMEDOUT) {
> >> +		log_error_regs(sec, doorbell);
> >> +		return FPGA_IMAGE_ERR_TIMEOUT;
> >> +	} else if (ret) {
> >> +		return FPGA_IMAGE_ERR_RW_ERROR;
> >> +	}
> >> +
> >> +	switch (rsu_stat(doorbell)) {
> >> +	case RSU_STAT_NORMAL:
> >> +	case RSU_STAT_NIOS_OK:
> >> +	case RSU_STAT_USER_OK:
> >> +	case RSU_STAT_FACTORY_OK:
> >> +		break;
> >> +	default:
> >> +		log_error_regs(sec, doorbell);
> >> +		return FPGA_IMAGE_ERR_HW_ERROR;
> >> +	}
> >> +
> >> +	return FPGA_IMAGE_ERR_NONE;
> >> +}
> >> +
> >> +static int rsu_check_complete(struct m10bmc_sec *sec, u32 *doorbell)
> >> +{
> >> +	if (m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, doorbell))
> >> +		return -EIO;
> >> +
> >> +	switch (rsu_stat(*doorbell)) {
> >> +	case RSU_STAT_NORMAL:
> >> +	case RSU_STAT_NIOS_OK:
> >> +	case RSU_STAT_USER_OK:
> >> +	case RSU_STAT_FACTORY_OK:
> >> +		break;
> >> +	default:
> >> +		return -EINVAL;
> >> +	}
> >> +
> >> +	switch (rsu_prog(*doorbell)) {
> >> +	case RSU_PROG_IDLE:
> >> +	case RSU_PROG_RSU_DONE:
> >> +		return 0;
> >> +	case RSU_PROG_AUTHENTICATING:
> >> +	case RSU_PROG_COPYING:
> >> +	case RSU_PROG_UPDATE_CANCEL:
> >> +	case RSU_PROG_PROGRAM_KEY_HASH:
> >> +		return -EAGAIN;
> >> +	default:
> >> +		return -EINVAL;
> >> +	}
> >> +}
> >> +
> >> +static enum fpga_image_err m10bmc_sec_prepare(struct fpga_image_load *imgld)
> >> +{
> >> +	struct m10bmc_sec *sec = imgld->priv;
> >> +	enum fpga_image_err ret;
> >> +
> >> +	if (imgld->remaining_size > M10BMC_STAGING_SIZE)
> >> +		return FPGA_IMAGE_ERR_INVALID_SIZE;
> >> +
> >> +	ret = rsu_check_idle(sec);
> >> +	if (ret != FPGA_IMAGE_ERR_NONE)
> >> +		return ret;
> >> +
> >> +	ret = rsu_update_init(sec);
> >> +	if (ret != FPGA_IMAGE_ERR_NONE)
> >> +		return ret;
> >> +
> >> +	return rsu_prog_ready(sec);
> >> +}
> >> +
> >> +#define WRITE_BLOCK_SIZE 0x4000 /* Update remaining_size every 0x4000 bytes */
> >> +
> >> +static enum fpga_image_err
> >> +m10bmc_sec_write_blk(struct fpga_image_load *imgld, u32 offset)
> >> +{
> >> +	struct m10bmc_sec *sec = imgld->priv;
> >> +	unsigned int stride = regmap_get_reg_stride(sec->m10bmc->regmap);
> >> +	u32 doorbell, blk_size;
> >> +	int ret;
> >> +
> >> +	ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
> >> +	if (ret) {
> >> +		return FPGA_IMAGE_ERR_RW_ERROR;
> >> +	} else if (rsu_prog(doorbell) != RSU_PROG_READY) {
> >> +		log_error_regs(sec, doorbell);
> >> +		return FPGA_IMAGE_ERR_HW_ERROR;
> >> +	}
> >> +
> >> +	blk_size = min_t(u32, imgld->remaining_size, WRITE_BLOCK_SIZE);
> >> +	ret = regmap_bulk_write(sec->m10bmc->regmap,
> >> +				M10BMC_STAGING_BASE + offset,
> >> +				(void *)imgld->data + offset,
> >> +				(blk_size + stride - 1) / stride);
> >> +
> >> +	if (ret)
> >> +		return FPGA_IMAGE_ERR_RW_ERROR;
> >> +
> >> +	imgld->remaining_size -= blk_size;
> >> +	return FPGA_IMAGE_ERR_NONE;
> >> +}
> >> +
> >> +/*
> >> + * m10bmc_sec_poll_complete() is called after handing things off to
> >> + * the BMC firmware. Depending on the type of update, it could be
> >> + * 30+ minutes before the BMC firmware completes the update. The
> >> + * imgld->driver_unload check allows the driver to be unloaded,
> >> + * but the BMC firmware will continue the update and no further
> >> + * secure updates can be started for this device until the update
> >> + * is complete.
> >> + */
> >> +static enum fpga_image_err m10bmc_sec_poll_complete(struct fpga_image_load *imgld)
> >> +{
> >> +	struct m10bmc_sec *sec = imgld->priv;
> >> +	unsigned long poll_timeout;
> >> +	enum fpga_image_err result;
> >> +	u32 doorbell;
> >> +	int ret;
> >> +
> >> +	result = rsu_send_data(sec);
> >> +	if (result != FPGA_IMAGE_ERR_NONE)
> >> +		return result;
> >> +
> >> +	poll_timeout = jiffies + msecs_to_jiffies(RSU_COMPLETE_TIMEOUT_MS);
> >> +	do {
> >> +		msleep(RSU_COMPLETE_INTERVAL_MS);
> >> +		ret = rsu_check_complete(sec, &doorbell);
> >> +		if (imgld->driver_unload)
> >> +			return FPGA_IMAGE_ERR_CANCELED;
> > Why we return CANCELED error code to user when driver unload is
> > requested?
> >
> > Users may think the update is failed and the old image is kept,
> > but in fact, the update continues and finally the old image is
> > replaced by the new one.
> 
> I could return FPGA_IMAGE_ERR_NONE, and then userspace code would
> think that the update completed without error, even though the
> update is still in progress.
> 
> Or I could create a new FPGA_IMAGE_ERR_EXIT code to indicate that
> the driver has exited while the update is still progressing.
> 
> I like the FPGA_IMAGE_ERR_EXIT option best of those two options.
> Any other suggestions?

I think if the driver could not actually cancel the update in some
progress, it should fail the driver unload request. Let the request
block.

If you just released the cancel call and let the module unload & machine
shutdown, the user image is corrupted.

Thanks,
Yilun

> 
> Thanks,
> - Russ
> 
> 
> >
> > Thanks,
> > Yilun
> >
> >> +	} while (ret == -EAGAIN && !time_after(jiffies, poll_timeout));
> >> +
> >> +	if (ret == -EAGAIN) {
> >> +		log_error_regs(sec, doorbell);
> >> +		return FPGA_IMAGE_ERR_TIMEOUT;
> >> +	} else if (ret == -EIO) {
> >> +		return FPGA_IMAGE_ERR_RW_ERROR;
> >> +	} else if (ret) {
> >> +		log_error_regs(sec, doorbell);
> >> +		return FPGA_IMAGE_ERR_HW_ERROR;
> >> +	}
> >> +
> >> +	return FPGA_IMAGE_ERR_NONE;
> >> +}
> >> +
> >> +static enum fpga_image_err m10bmc_sec_cancel(struct fpga_image_load *imgld)
> >> +{
> >> +	struct m10bmc_sec *sec = imgld->priv;
> >> +	u32 doorbell;
> >> +	int ret;
> >> +
> >> +	ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
> >> +	if (ret)
> >> +		return FPGA_IMAGE_ERR_RW_ERROR;
> >> +
> >> +	if (rsu_prog(doorbell) != RSU_PROG_READY)
> >> +		return FPGA_IMAGE_ERR_BUSY;
> >> +
> >> +	ret = regmap_update_bits(sec->m10bmc->regmap,
> >> +				 M10BMC_SYS_BASE + M10BMC_DOORBELL,
> >> +				 DRBL_HOST_STATUS,
> >> +				 FIELD_PREP(DRBL_HOST_STATUS,
> >> +					    HOST_STATUS_ABORT_RSU));
> >> +
> >> +	return ret ? FPGA_IMAGE_ERR_RW_ERROR : FPGA_IMAGE_ERR_NONE;
> >> +}
> >> +
> >> +static const struct fpga_image_load_ops m10bmc_lops = {
> >> +	.prepare = m10bmc_sec_prepare,
> >> +	.write_blk = m10bmc_sec_write_blk,
> >> +	.poll_complete = m10bmc_sec_poll_complete,
> >> +	.cancel = m10bmc_sec_cancel,
> >> +};
> >>  
> >>  static int m10bmc_secure_probe(struct platform_device *pdev)
> >>  {
> >> -- 
> >> 2.25.1

Re: [PATCH v14 1/4] fpga: m10bmc-sec: create max10 bmc secure update driver

[Tom Rix]

On 9/12/21 10:37 PM, Xu Yilun wrote:
> On Sat, Sep 11, 2021 at 12:04:07PM -0700, Tom Rix wrote:
>> On 9/10/21 1:27 PM, Russ Weight wrote:
>>> On 9/10/21 8:13 AM, Xu Yilun wrote:
>>>> On Thu, Sep 09, 2021 at 04:33:01PM -0700, Russ Weight wrote:
>>>>> Create a sub driver for the FPGA Card BMC in order to support secure
>>>>> updates.  This sub-driver will invoke an instance of the FPGA Image Load
>>>>> class driver for the image load portion of the update.
>>>>>
>>>>> This patch creates the MAX10 BMC Secure Update driver and provides sysfs
>>>>> files 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@intel.com>
>>>>> Reviewed-by: Tom Rix <trix@redhat.com>
>>>>> ---
>>>>> v14:
>>>>>     - Changed symbol and text references to reflect the renaming of the
>>>>>       Security Manager Class driver to FPGA Image Load.
>>>>> v13:
>>>>>     - Updated copyright to 2021
>>>>>     - Updated ABI documentation date and kernel version
>>>>>     - Call updated fpga_sec_mgr_register() and fpga_sec_mgr_unregister()
>>>>>       functions instead of devm_fpga_sec_mgr_create() and
>>>>>       devm_fpga_sec_mgr_register().
>>>>> v12:
>>>>>     - Updated Date and KernelVersion fields in ABI documentation
>>>>> v11:
>>>>>     - Added Reviewed-by tag
>>>>> v10:
>>>>>     - Changed the path expressions in the sysfs documentation to
>>>>>       replace the n3000 reference with something more generic to
>>>>>       accomodate other devices that use the same driver.
>>>>> v9:
>>>>>     - Rebased to 5.12-rc2 next
>>>>>     - Updated Date and KernelVersion in ABI documentation
>>>>> v8:
>>>>>     - Previously patch 2/6, otherwise no change
>>>>> v7:
>>>>>     - Updated Date and KernelVersion in ABI documentation
>>>>> v6:
>>>>>     - Added WARN_ON() call for (sha_num_bytes / stride) to assert
>>>>>       that the proper count is passed to regmap_bulk_read().
>>>>> v5:
>>>>>     - No change
>>>>> v4:
>>>>>     - Moved sysfs files for displaying the root entry hashes (REH)
>>>>>       from the FPGA Security Manager class driver to here. The
>>>>>       m10bmc_reh() and m10bmc_reh_size() functions are removed and
>>>>>       the functionality from these functions is moved into a
>>>>>       show_root_entry_hash() function for displaying the REHs.
>>>>>     - Added ABI documentation for the new sysfs entries:
>>>>>       sysfs-driver-intel-m10-bmc-secure
>>>>>     - Updated the MAINTAINERS file to add the new ABI documentation
>>>>>       file: sysfs-driver-intel-m10-bmc-secure
>>>>>     - Removed unnecessary ret variable from m10bmc_secure_probe()
>>>>>     - Incorporated new devm_fpga_sec_mgr_register() function into
>>>>>       m10bmc_secure_probe() and removed the m10bmc_secure_remove()
>>>>>       function.
>>>>> v3:
>>>>>     - Changed from "Intel FPGA Security Manager" to FPGA Security Manager"
>>>>>     - Changed: iops -> sops, imgr -> smgr, IFPGA_ -> FPGA_, ifpga_ to fpga_
>>>>>     - Changed "MAX10 BMC Secure Engine driver" to "MAX10 BMC Secure
>>>>>       Update driver"
>>>>>     - Removed wrapper functions (m10bmc_raw_*, m10bmc_sys_*). The
>>>>>       underlying functions are now called directly.
>>>>>     - Changed "_root_entry_hash" to "_reh", with a comment explaining
>>>>>       what reh is.
>>>>> 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().
>>>>> ---
>>>>>    .../testing/sysfs-driver-intel-m10-bmc-secure |  29 ++++
>>>>>    MAINTAINERS                                   |   2 +
>>>>>    drivers/fpga/Kconfig                          |  11 ++
>>>>>    drivers/fpga/Makefile                         |   3 +
>>>>>    drivers/fpga/intel-m10-bmc-secure.c           | 145 ++++++++++++++++++
>>>>>    5 files changed, 190 insertions(+)
>>>>>    create mode 100644 Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
>>>>>    create mode 100644 drivers/fpga/intel-m10-bmc-secure.c
>>>>>
>>>>> diff --git a/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
>>>>> new file mode 100644
>>>>> index 000000000000..363403ce992d
>>>>> --- /dev/null
>>>>> +++ b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
>>>>> @@ -0,0 +1,29 @@
>>>>> +What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/sr_root_entry_hash
>>>>> +Date:		Aug 2021
>>>>> +KernelVersion:	5.15
>>>>> +Contact:	Russ Weight <russell.h.weight@intel.com>
>>>>> +Description:	Read only. Returns the root entry hash for the static
>>>>> +		region if one is programmed, else it returns the
>>>>> +		string: "hash not programmed".  This file is only
>>>>> +		visible if the underlying device supports it.
>>>>> +		Format: "0x%x".
>>>>> +
>>>>> +What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/pr_root_entry_hash
>>>>> +Date:		Aug 2021
>>>>> +KernelVersion:	5.15
>>>>> +Contact:	Russ Weight <russell.h.weight@intel.com>
>>>>> +Description:	Read only. Returns the root entry hash for the partial
>>>>> +		reconfiguration region if one is programmed, else it
>>>>> +		returns the string: "hash not programmed".  This file
>>>>> +		is only visible if the underlying device supports it.
>>>>> +		Format: "0x%x".
>>>>> +
>>>>> +What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/bmc_root_entry_hash
>>>>> +Date:		Aug 2021
>>>>> +KernelVersion:	5.15
>>>>> +Contact:	Russ Weight <russell.h.weight@intel.com>
>>>>> +Description:	Read only. Returns the root entry hash for the BMC image
>>>>> +		if one is programmed, else it returns the string:
>>>>> +		"hash not programmed".  This file is only visible if the
>>>>> +		underlying device supports it.
>>>>> +		Format: "0x%x".
>>>>> diff --git a/MAINTAINERS b/MAINTAINERS
>>>>> index e3fbc1bde9bc..cf93835b4775 100644
>>>>> --- a/MAINTAINERS
>>>>> +++ b/MAINTAINERS
>>>>> @@ -7363,8 +7363,10 @@ M:	Russ Weight <russell.h.weight@intel.com>
>>>>>    L:	linux-fpga@vger.kernel.org
>>>>>    S:	Maintained
>>>>>    F:	Documentation/ABI/testing/sysfs-class-fpga-image-load
>>>>> +F:	Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
>>>> Should we change the name of the driver? Some keywords like "image load"
>>>> or "firmware update" should be in the name.
>>> I considered that. The image-upload functionality is a subset of  this
>>> driver. It also exposes security collateral via sysfs, and the image-load
>>> triggers and power-on-image sysfs files will probably end up in this
>>> driver too.
>>>
>>> The current driver name is intel-m10-bmc-secure. Do we need to keep
>>> "intel-m10-bmc" in the name?
>>>
>>> intel-m10-bmc-sec-fw-update?
>>> intel-m10-bmc-sec-update?
>>>
>>> What do you think? Any other suggestions?
> The single word "secure" is quite indistinct to me. I think
> intel-m10-bmc-sec-update is much better.

This fine.

Should it move to mfd/ ?

Tom

>
>> The prefix intel-m10-bmc-sec is clunky and confuses me because I think of
>> mfd/intel-m10-bmc.c
> The secure update engine is now implemented in MAX10 bmc. The driver
> code also assumes it is always a sub device of MAX10 bmc. So my
> preference is we keep the prefix.
>
>> How about
>>
>> dfl-image-load ?
> There may be several secure update engines for DFL based FPGAs. So we
> may be more specific.
>
> Thanks,
> Yilun
>

Re: [PATCH v14 1/4] fpga: m10bmc-sec: create max10 bmc secure update driver

[Xu Yilun]

On Mon, Sep 13, 2021 at 05:12:32AM -0700, Tom Rix wrote:
> 
> On 9/12/21 10:37 PM, Xu Yilun wrote:
> > On Sat, Sep 11, 2021 at 12:04:07PM -0700, Tom Rix wrote:
> > > On 9/10/21 1:27 PM, Russ Weight wrote:
> > > > On 9/10/21 8:13 AM, Xu Yilun wrote:
> > > > > On Thu, Sep 09, 2021 at 04:33:01PM -0700, Russ Weight wrote:
> > > > > > Create a sub driver for the FPGA Card BMC in order to support secure
> > > > > > updates.  This sub-driver will invoke an instance of the FPGA Image Load
> > > > > > class driver for the image load portion of the update.
> > > > > > 
> > > > > > This patch creates the MAX10 BMC Secure Update driver and provides sysfs
> > > > > > files 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@intel.com>
> > > > > > Reviewed-by: Tom Rix <trix@redhat.com>
> > > > > > ---
> > > > > > v14:
> > > > > >     - Changed symbol and text references to reflect the renaming of the
> > > > > >       Security Manager Class driver to FPGA Image Load.
> > > > > > v13:
> > > > > >     - Updated copyright to 2021
> > > > > >     - Updated ABI documentation date and kernel version
> > > > > >     - Call updated fpga_sec_mgr_register() and fpga_sec_mgr_unregister()
> > > > > >       functions instead of devm_fpga_sec_mgr_create() and
> > > > > >       devm_fpga_sec_mgr_register().
> > > > > > v12:
> > > > > >     - Updated Date and KernelVersion fields in ABI documentation
> > > > > > v11:
> > > > > >     - Added Reviewed-by tag
> > > > > > v10:
> > > > > >     - Changed the path expressions in the sysfs documentation to
> > > > > >       replace the n3000 reference with something more generic to
> > > > > >       accomodate other devices that use the same driver.
> > > > > > v9:
> > > > > >     - Rebased to 5.12-rc2 next
> > > > > >     - Updated Date and KernelVersion in ABI documentation
> > > > > > v8:
> > > > > >     - Previously patch 2/6, otherwise no change
> > > > > > v7:
> > > > > >     - Updated Date and KernelVersion in ABI documentation
> > > > > > v6:
> > > > > >     - Added WARN_ON() call for (sha_num_bytes / stride) to assert
> > > > > >       that the proper count is passed to regmap_bulk_read().
> > > > > > v5:
> > > > > >     - No change
> > > > > > v4:
> > > > > >     - Moved sysfs files for displaying the root entry hashes (REH)
> > > > > >       from the FPGA Security Manager class driver to here. The
> > > > > >       m10bmc_reh() and m10bmc_reh_size() functions are removed and
> > > > > >       the functionality from these functions is moved into a
> > > > > >       show_root_entry_hash() function for displaying the REHs.
> > > > > >     - Added ABI documentation for the new sysfs entries:
> > > > > >       sysfs-driver-intel-m10-bmc-secure
> > > > > >     - Updated the MAINTAINERS file to add the new ABI documentation
> > > > > >       file: sysfs-driver-intel-m10-bmc-secure
> > > > > >     - Removed unnecessary ret variable from m10bmc_secure_probe()
> > > > > >     - Incorporated new devm_fpga_sec_mgr_register() function into
> > > > > >       m10bmc_secure_probe() and removed the m10bmc_secure_remove()
> > > > > >       function.
> > > > > > v3:
> > > > > >     - Changed from "Intel FPGA Security Manager" to FPGA Security Manager"
> > > > > >     - Changed: iops -> sops, imgr -> smgr, IFPGA_ -> FPGA_, ifpga_ to fpga_
> > > > > >     - Changed "MAX10 BMC Secure Engine driver" to "MAX10 BMC Secure
> > > > > >       Update driver"
> > > > > >     - Removed wrapper functions (m10bmc_raw_*, m10bmc_sys_*). The
> > > > > >       underlying functions are now called directly.
> > > > > >     - Changed "_root_entry_hash" to "_reh", with a comment explaining
> > > > > >       what reh is.
> > > > > > 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().
> > > > > > ---
> > > > > >    .../testing/sysfs-driver-intel-m10-bmc-secure |  29 ++++
> > > > > >    MAINTAINERS                                   |   2 +
> > > > > >    drivers/fpga/Kconfig                          |  11 ++
> > > > > >    drivers/fpga/Makefile                         |   3 +
> > > > > >    drivers/fpga/intel-m10-bmc-secure.c           | 145 ++++++++++++++++++
> > > > > >    5 files changed, 190 insertions(+)
> > > > > >    create mode 100644 Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
> > > > > >    create mode 100644 drivers/fpga/intel-m10-bmc-secure.c
> > > > > > 
> > > > > > diff --git a/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
> > > > > > new file mode 100644
> > > > > > index 000000000000..363403ce992d
> > > > > > --- /dev/null
> > > > > > +++ b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
> > > > > > @@ -0,0 +1,29 @@
> > > > > > +What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/sr_root_entry_hash
> > > > > > +Date:		Aug 2021
> > > > > > +KernelVersion:	5.15
> > > > > > +Contact:	Russ Weight <russell.h.weight@intel.com>
> > > > > > +Description:	Read only. Returns the root entry hash for the static
> > > > > > +		region if one is programmed, else it returns the
> > > > > > +		string: "hash not programmed".  This file is only
> > > > > > +		visible if the underlying device supports it.
> > > > > > +		Format: "0x%x".
> > > > > > +
> > > > > > +What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/pr_root_entry_hash
> > > > > > +Date:		Aug 2021
> > > > > > +KernelVersion:	5.15
> > > > > > +Contact:	Russ Weight <russell.h.weight@intel.com>
> > > > > > +Description:	Read only. Returns the root entry hash for the partial
> > > > > > +		reconfiguration region if one is programmed, else it
> > > > > > +		returns the string: "hash not programmed".  This file
> > > > > > +		is only visible if the underlying device supports it.
> > > > > > +		Format: "0x%x".
> > > > > > +
> > > > > > +What:		/sys/bus/platform/drivers/intel-m10bmc-secure/.../security/bmc_root_entry_hash
> > > > > > +Date:		Aug 2021
> > > > > > +KernelVersion:	5.15
> > > > > > +Contact:	Russ Weight <russell.h.weight@intel.com>
> > > > > > +Description:	Read only. Returns the root entry hash for the BMC image
> > > > > > +		if one is programmed, else it returns the string:
> > > > > > +		"hash not programmed".  This file is only visible if the
> > > > > > +		underlying device supports it.
> > > > > > +		Format: "0x%x".
> > > > > > diff --git a/MAINTAINERS b/MAINTAINERS
> > > > > > index e3fbc1bde9bc..cf93835b4775 100644
> > > > > > --- a/MAINTAINERS
> > > > > > +++ b/MAINTAINERS
> > > > > > @@ -7363,8 +7363,10 @@ M:	Russ Weight <russell.h.weight@intel.com>
> > > > > >    L:	linux-fpga@vger.kernel.org
> > > > > >    S:	Maintained
> > > > > >    F:	Documentation/ABI/testing/sysfs-class-fpga-image-load
> > > > > > +F:	Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure
> > > > > Should we change the name of the driver? Some keywords like "image load"
> > > > > or "firmware update" should be in the name.
> > > > I considered that. The image-upload functionality is a subset of  this
> > > > driver. It also exposes security collateral via sysfs, and the image-load
> > > > triggers and power-on-image sysfs files will probably end up in this
> > > > driver too.
> > > > 
> > > > The current driver name is intel-m10-bmc-secure. Do we need to keep
> > > > "intel-m10-bmc" in the name?
> > > > 
> > > > intel-m10-bmc-sec-fw-update?
> > > > intel-m10-bmc-sec-update?
> > > > 
> > > > What do you think? Any other suggestions?
> > The single word "secure" is quite indistinct to me. I think
> > intel-m10-bmc-sec-update is much better.
> 
> This fine.
> 
> Should it move to mfd/ ?

I think not. The mfd folder only contains MFD parent device drivers. The
subdev drivers are placed in various class folder according to their own
functionality.

Thanks,
Yilun

> 
> Tom
> 
> > 
> > > The prefix intel-m10-bmc-sec is clunky and confuses me because I think of
> > > mfd/intel-m10-bmc.c
> > The secure update engine is now implemented in MAX10 bmc. The driver
> > code also assumes it is always a sub device of MAX10 bmc. So my
> > preference is we keep the prefix.
> > 
> > > How about
> > > 
> > > dfl-image-load ?
> > There may be several secure update engines for DFL based FPGAs. So we
> > may be more specific.
> > 
> > Thanks,
> > Yilun
> >