[PATCH v1 1/1] platform/mellanox: Add bootctl driver for Mellanox BlueField Soc
From: Liming Sun
Date: Tue Jan 29 2019 - 15:59:45 EST
This commit adds the bootctl platform driver for Mellanox BlueField
Soc, which controls the eMMC boot partition swapping and related
watchdog configuration.
Reviewed-by: David Woods <dwoods@xxxxxxxxxxxx>
Signed-off-by: Liming Sun <lsun@xxxxxxxxxxxx>
---
drivers/platform/mellanox/Kconfig | 15 +-
drivers/platform/mellanox/Makefile | 1 +
drivers/platform/mellanox/mlxbf-bootctl.c | 317 ++++++++++++++++++++++++++++++
drivers/platform/mellanox/mlxbf-bootctl.h | 108 ++++++++++
4 files changed, 440 insertions(+), 1 deletion(-)
create mode 100644 drivers/platform/mellanox/mlxbf-bootctl.c
create mode 100644 drivers/platform/mellanox/mlxbf-bootctl.h
diff --git a/drivers/platform/mellanox/Kconfig b/drivers/platform/mellanox/Kconfig
index cd8a908..580901f 100644
--- a/drivers/platform/mellanox/Kconfig
+++ b/drivers/platform/mellanox/Kconfig
@@ -5,7 +5,7 @@
menuconfig MELLANOX_PLATFORM
bool "Platform support for Mellanox hardware"
- depends on X86 || ARM || COMPILE_TEST
+ depends on X86 || ARM || ARM64 || COMPILE_TEST
---help---
Say Y here to get to see options for platform support for
Mellanox systems. This option alone does not add any kernel code.
@@ -34,4 +34,17 @@ config MLXREG_IO
to system resets operation, system reset causes monitoring and some
kinds of mux selection.
+config MLXBF_BOOTCTL
+ tristate "Mellanox BlueField Firmware Boot Control driver"
+ depends on ARM64
+ default m
+ help
+ The Mellanox BlueField firmware implements functionality to
+ request swapping the primary and alternate eMMC boot
+ partition, and to set up a watchdog that can undo that swap
+ if the system does not boot up correctly. This driver
+ provides sysfs access to the firmware, to be used in
+ conjunction with the eMMC device driver to do any necessary
+ initial swap of the boot partition.
+
endif # MELLANOX_PLATFORM
diff --git a/drivers/platform/mellanox/Makefile b/drivers/platform/mellanox/Makefile
index 57074d9c..76b0370 100644
--- a/drivers/platform/mellanox/Makefile
+++ b/drivers/platform/mellanox/Makefile
@@ -5,3 +5,4 @@
#
obj-$(CONFIG_MLXREG_HOTPLUG) += mlxreg-hotplug.o
obj-$(CONFIG_MLXREG_IO) += mlxreg-io.o
+obj-$(CONFIG_MLXBF_BOOTCTL) += mlxbf-bootctl.o
diff --git a/drivers/platform/mellanox/mlxbf-bootctl.c b/drivers/platform/mellanox/mlxbf-bootctl.c
new file mode 100644
index 0000000..90a655b
--- /dev/null
+++ b/drivers/platform/mellanox/mlxbf-bootctl.c
@@ -0,0 +1,317 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Mellanox boot control driver
+ * This driver provides a sysfs interface for systems management
+ * software to manage reset-time actions.
+ *
+ * Copyright (C) 2019 Mellanox Technologies
+ */
+
+#include <linux/acpi.h>
+#include <linux/arm-smccc.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include "mlxbf-bootctl.h"
+
+#define MLXBF_BOOTCTL_DRIVER_NAME "mlxbf-bootctl"
+#define MLXBF_BOOTCTL_DRIVER_VERSION "1.2"
+#define MLXBF_BOOTCTL_DRIVER_DESCRIPTION "Mellanox boot control driver"
+
+#define MLXBF_BOOTCTL_SB_MODE_SECURE_MASK 0x03
+#define MLXBF_BOOTCTL_SB_MODE_TEST_MASK 0x0c
+
+#define MLXBF_SB_KEY_NUM 4
+
+struct mlxbf_bootctl_name {
+ int value;
+ const char name[12];
+};
+
+static struct mlxbf_bootctl_name boot_names[] = {
+ { MLXBF_BOOTCTL_EXTERNAL, "external" },
+ { MLXBF_BOOTCTL_EMMC, "emmc" },
+ { MLNX_BOOTCTL_SWAP_EMMC, "swap_emmc" },
+ { MLXBF_BOOTCTL_EMMC_LEGACY, "emmc_legacy" },
+ { MLXBF_BOOTCTL_NONE, "none" },
+ { -1, "" }
+};
+
+static char mlxbf_bootctl_lifecycle_states[][16] = {
+ [0] = "soft_non_secure",
+ [1] = "secure",
+ [2] = "hard_non_secure",
+ [3] = "rma",
+};
+
+/* The SMC calls in question are atomic, so we don't have to lock here. */
+static int mlxbf_bootctl_smc_call1(unsigned int smc_op, int smc_arg)
+{
+ struct arm_smccc_res res;
+
+ arm_smccc_smc(smc_op, smc_arg, 0, 0, 0, 0, 0, 0, &res);
+
+ return res.a0;
+}
+
+/* Syntactic sugar to avoid having to specify an unused argument. */
+#define mlxbf_bootctl_smc_call0(smc_op) mlxbf_bootctl_smc_call1(smc_op, 0)
+
+static int reset_action_to_val(const char *action, size_t len)
+{
+ struct mlxbf_bootctl_name *bn;
+
+ /* Accept string either with or without a newline terminator */
+ if (action[len-1] == '\n')
+ --len;
+
+ for (bn = boot_names; bn->value >= 0; ++bn)
+ if (strncmp(bn->name, action, len) == 0)
+ break;
+
+ return bn->value;
+}
+
+static const char *reset_action_to_string(int action)
+{
+ struct mlxbf_bootctl_name *bn;
+
+ for (bn = boot_names; bn->value >= 0; ++bn)
+ if (bn->value == action)
+ break;
+
+ return bn->name;
+}
+
+static ssize_t post_reset_wdog_show(struct device_driver *drv, char *buf)
+{
+ return sprintf(buf, "%d\n",
+ mlxbf_bootctl_smc_call0(MLXBF_BOOTCTL_GET_POST_RESET_WDOG));
+}
+
+static ssize_t post_reset_wdog_store(struct device_driver *drv,
+ const char *buf, size_t count)
+{
+ int err;
+ unsigned long watchdog;
+
+ err = kstrtoul(buf, 10, &watchdog);
+ if (err)
+ return err;
+
+ if (mlxbf_bootctl_smc_call1(MLXBF_BOOTCTL_SET_POST_RESET_WDOG,
+ watchdog) < 0)
+ return -EINVAL;
+
+ return count;
+}
+
+static ssize_t reset_action_show(struct device_driver *drv, char *buf)
+{
+ return sprintf(buf, "%s\n", reset_action_to_string(
+ mlxbf_bootctl_smc_call0(MLXBF_BOOTCTL_GET_RESET_ACTION)));
+}
+
+static ssize_t reset_action_store(struct device_driver *drv,
+ const char *buf, size_t count)
+{
+ int action = reset_action_to_val(buf, count);
+
+ if (action < 0 || action == MLXBF_BOOTCTL_NONE)
+ return -EINVAL;
+
+ if (mlxbf_bootctl_smc_call1(MLXBF_BOOTCTL_SET_RESET_ACTION, action) < 0)
+ return -EINVAL;
+
+ return count;
+}
+
+static ssize_t second_reset_action_show(struct device_driver *drv, char *buf)
+{
+ return sprintf(buf, "%s\n", reset_action_to_string(
+ mlxbf_bootctl_smc_call0(
+ MLXBF_BOOTCTL_GET_SECOND_RESET_ACTION)));
+}
+
+static ssize_t second_reset_action_store(struct device_driver *drv,
+ const char *buf, size_t count)
+{
+ int action = reset_action_to_val(buf, count);
+
+ if (action < 0)
+ return -EINVAL;
+
+ if (mlxbf_bootctl_smc_call1(MLXBF_BOOTCTL_SET_SECOND_RESET_ACTION,
+ action) < 0)
+ return -EINVAL;
+
+ return count;
+}
+
+static ssize_t lifecycle_state_show(struct device_driver *drv, char *buf)
+{
+ int lc_state = mlxbf_bootctl_smc_call1(
+ MLXBF_BOOTCTL_GET_TBB_FUSE_STATUS,
+ MLXBF_BOOTCTL_FUSE_STATUS_LIFECYCLE);
+
+ if (lc_state < 0)
+ return -EINVAL;
+
+ lc_state &= (MLXBF_BOOTCTL_SB_MODE_TEST_MASK |
+ MLXBF_BOOTCTL_SB_MODE_SECURE_MASK);
+ /*
+ * If the test bits are set, we specify that the current state may be
+ * due to using the test bits.
+ */
+ if ((lc_state & MLXBF_BOOTCTL_SB_MODE_TEST_MASK) != 0) {
+
+ lc_state &= MLXBF_BOOTCTL_SB_MODE_SECURE_MASK;
+
+ return sprintf(buf, "%s(test)\n",
+ mlxbf_bootctl_lifecycle_states[lc_state]);
+ }
+
+ return sprintf(buf, "%s\n", mlxbf_bootctl_lifecycle_states[lc_state]);
+}
+
+static ssize_t secure_boot_fuse_state_show(struct device_driver *drv, char *buf)
+{
+ int key;
+ int buf_len = 0;
+ int upper_key_used = 0;
+ int sb_key_state = mlxbf_bootctl_smc_call1(
+ MLXBF_BOOTCTL_GET_TBB_FUSE_STATUS,
+ MLXBF_BOOTCTL_FUSE_STATUS_KEYS);
+
+ if (sb_key_state < 0)
+ return -EINVAL;
+
+ for (key = MLXBF_SB_KEY_NUM - 1; key >= 0; key--) {
+ int burnt = ((sb_key_state & (1 << key)) != 0);
+ int valid = ((sb_key_state &
+ (1 << (key + MLXBF_SB_KEY_NUM))) != 0);
+
+ buf_len += sprintf(buf + buf_len, "Ver%d:", key);
+ if (upper_key_used) {
+ if (burnt) {
+ if (valid)
+ buf_len += sprintf(buf + buf_len,
+ "Used");
+ else
+ buf_len += sprintf(buf + buf_len,
+ "Wasted");
+ } else {
+ if (valid)
+ buf_len += sprintf(buf + buf_len,
+ "Invalid");
+ else
+ buf_len += sprintf(buf + buf_len,
+ "Skipped");
+ }
+ } else {
+ if (burnt) {
+ if (valid) {
+ upper_key_used = 1;
+ buf_len += sprintf(buf + buf_len,
+ "In use");
+ } else
+ buf_len += sprintf(buf + buf_len,
+ "Burn incomplete");
+ } else {
+ if (valid)
+ buf_len += sprintf(buf + buf_len,
+ "Invalid");
+ else
+ buf_len += sprintf(buf + buf_len,
+ "Free");
+ }
+ }
+ buf_len += sprintf(buf + buf_len, "\n");
+ }
+
+ return buf_len;
+}
+
+#define MLXBF_BOOTCTL_DRV_ATTR(_name) DRIVER_ATTR_RW(_name)
+
+static MLXBF_BOOTCTL_DRV_ATTR(post_reset_wdog);
+static MLXBF_BOOTCTL_DRV_ATTR(reset_action);
+static MLXBF_BOOTCTL_DRV_ATTR(second_reset_action);
+static DRIVER_ATTR_RO(lifecycle_state);
+static DRIVER_ATTR_RO(secure_boot_fuse_state);
+
+static struct attribute *mlxbf_bootctl_dev_attrs[] = {
+ &driver_attr_post_reset_wdog.attr,
+ &driver_attr_reset_action.attr,
+ &driver_attr_second_reset_action.attr,
+ &driver_attr_lifecycle_state.attr,
+ &driver_attr_secure_boot_fuse_state.attr,
+ NULL
+};
+
+static struct attribute_group mlxbf_bootctl_attr_group = {
+ .attrs = mlxbf_bootctl_dev_attrs
+};
+
+static const struct attribute_group *mlxbf_bootctl_attr_groups[] = {
+ &mlxbf_bootctl_attr_group,
+ NULL
+};
+
+static const struct acpi_device_id mlxbf_bootctl_acpi_ids[] = {
+ {"MLNXBF04", 0},
+ {},
+};
+
+MODULE_DEVICE_TABLE(acpi, mlxbf_bootctl_acpi_ids);
+
+static int mlxbf_bootctl_probe(struct platform_device *pdev)
+{
+ struct arm_smccc_res res;
+
+ /*
+ * Ensure we have the UUID we expect for this service.
+ * Note that the functionality we want is present in the first
+ * released version of this service, so we don't check the version.
+ */
+ arm_smccc_smc(MLXBF_BOOTCTL_SIP_SVC_UID, 0, 0, 0, 0, 0, 0, 0, &res);
+ if (res.a0 != 0x89c036b4 || res.a1 != 0x11e6e7d7 ||
+ res.a2 != 0x1a009787 || res.a3 != 0xc4bf00ca)
+ return -ENODEV;
+
+ /*
+ * When watchdog is used, it sets boot mode to MLXBF_BOOTCTL_SWAP_EMMC
+ * in case of boot failures. However it doesn't clear the state if there
+ * is no failure. Restore the default boot mode here to avoid any
+ * unnecessary boot partition swapping.
+ */
+ if (mlxbf_bootctl_smc_call1(MLXBF_BOOTCTL_SET_RESET_ACTION,
+ MLXBF_BOOTCTL_EMMC) < 0)
+ pr_err("Unable to reset the EMMC boot mode\n");
+
+ pr_info("%s (version %s)\n", MLXBF_BOOTCTL_DRIVER_DESCRIPTION,
+ MLXBF_BOOTCTL_DRIVER_VERSION);
+
+ return 0;
+}
+
+static int mlxbf_bootctl_remove(struct platform_device *pdev)
+{
+ return 0;
+}
+
+static struct platform_driver mlxbf_bootctl_driver = {
+ .probe = mlxbf_bootctl_probe,
+ .remove = mlxbf_bootctl_remove,
+ .driver = {
+ .name = MLXBF_BOOTCTL_DRIVER_NAME,
+ .groups = mlxbf_bootctl_attr_groups,
+ .acpi_match_table = ACPI_PTR(mlxbf_bootctl_acpi_ids),
+ }
+};
+
+module_platform_driver(mlxbf_bootctl_driver);
+
+MODULE_DESCRIPTION(DRIVER_DESCRIPTION);
+MODULE_VERSION(MLXBF_BOOTCTL_DRIVER_VERSION);
+MODULE_AUTHOR("Mellanox Technologies");
+MODULE_LICENSE("GPL");
diff --git a/drivers/platform/mellanox/mlxbf-bootctl.h b/drivers/platform/mellanox/mlxbf-bootctl.h
new file mode 100644
index 0000000..0592ce4
--- /dev/null
+++ b/drivers/platform/mellanox/mlxbf-bootctl.h
@@ -0,0 +1,108 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2019, Mellanox Technologies. All rights reserved.
+ */
+
+#ifndef __MLXBF_BOOTCTL_H__
+#define __MLXBF_BOOTCTL_H__
+
+/*
+ * Request that the on-chip watchdog be enabled, or disabled, after
+ * the next chip soft reset. This call does not affect the current
+ * status of the on-chip watchdog. If non-zero, the argument
+ * specifies the watchdog interval in seconds. If zero, the watchdog
+ * will not be enabled after the next soft reset. Non-zero errors are
+ * returned as documented below.
+ */
+#define MLXBF_BOOTCTL_SET_POST_RESET_WDOG 0x82000000
+
+/*
+ * Query the status which has been requested for the on-chip watchdog
+ * after the next chip soft reset. Returns the interval as set by
+ * MLXBF_BOOTCTL_SET_POST_RESET_WDOG.
+ */
+#define MLXBF_BOOTCTL_GET_POST_RESET_WDOG 0x82000001
+
+/*
+ * Request that a specific boot action be taken at the next soft
+ * reset. By default, the boot action is set by external chip pins,
+ * which are sampled on hard reset. Note that the boot action
+ * requested by this call will persist on subsequent resets unless
+ * this service, or the MLNX_SET_SECOND_RESET_ACTION service, is
+ * invoked. See below for the available MLNX_BOOT_xxx parameter
+ * values. Non-zero errors are returned as documented below.
+ */
+#define MLXBF_BOOTCTL_SET_RESET_ACTION 0x82000002
+
+/*
+ * Return the specific boot action which will be taken at the next
+ * soft reset. Returns the reset action (see below for the parameter
+ * values for MLXBF_BOOTCTL_SET_RESET_ACTION).
+ */
+#define MLXBF_BOOTCTL_GET_RESET_ACTION 0x82000003
+
+/*
+ * Request that a specific boot action be taken at the soft reset
+ * after the next soft reset. For a specified valid boot mode, the
+ * effect of this call is identical to that of invoking
+ * MLXBF_BOOTCTL_SET_RESET_ACTION after the next chip soft reset; in
+ * particular, after that reset, the action for the now next reset can
+ * be queried with MLXBF_BOOTCTL_GET_RESET_ACTION and modified with
+ * MLXBF_BOOTCTL_SET_RESET_ACTION. You may also specify the parameter as
+ * MLNX_BOOT_NONE, which is equivalent to specifying that no call to
+ * MLXBF_BOOTCTL_SET_RESET_ACTION be taken after the next chip soft reset.
+ * This call does not affect the action to be taken at the next soft
+ * reset. Non-zero errors are returned as documented below.
+ */
+#define MLXBF_BOOTCTL_SET_SECOND_RESET_ACTION 0x82000004
+
+/*
+ * Return the specific boot action which will be taken at the soft
+ * reset after the next soft reset; this will be one of the valid
+ * actions for MLXBF_BOOTCTL_SET_SECOND_RESET_ACTION.
+ */
+#define MLXBF_BOOTCTL_GET_SECOND_RESET_ACTION 0x82000005
+
+/*
+ * Return the fuse status of the current chip. The caller should specify
+ * with the second argument if the state of the lifecycle fuses or the
+ * version of secure boot fuse keys left should be returned.
+ */
+#define MLXBF_BOOTCTL_GET_TBB_FUSE_STATUS 0x82000006
+
+/*
+ * Reset eMMC by programming the RST_N register.
+ */
+#define MLXBF_BOOTCTL_SET_EMMC_RST_N 0x82000007
+
+#define MLXBF_BOOTCTL_GET_DIMM_INFO 0x82000008
+
+/* SMC function IDs for SiP Service queries */
+#define MLXBF_BOOTCTL_SIP_SVC_CALL_COUNT 0x8200ff00
+#define MLXBF_BOOTCTL_SIP_SVC_UID 0x8200ff01
+#define MLXBF_BOOTCTL_SIP_SVC_VERSION 0x8200ff03
+
+/* ARM Standard Service Calls version numbers */
+#define MLXBF_BOOTCTL_SVC_VERSION_MAJOR 0x0
+#define MLXBF_BOOTCTL_SVC_VERSION_MINOR 0x2
+
+/* Number of svc calls defined. */
+#define MLXBF_BOOTCTL_NUM_SVC_CALLS 12
+
+/* Valid reset actions for MLXBF_BOOTCTL_SET_RESET_ACTION. */
+#define MLXBF_BOOTCTL_EXTERNAL 0 /* Not boot from eMMC */
+#define MLXBF_BOOTCTL_EMMC 1 /* From primary eMMC boot partition */
+#define MLNX_BOOTCTL_SWAP_EMMC 2 /* Swap eMMC boot partitions and reboot */
+#define MLXBF_BOOTCTL_EMMC_LEGACY 3 /* From primary eMMC in legacy mode */
+
+/* Valid arguments for requesting the fuse status. */
+#define MLXBF_BOOTCTL_FUSE_STATUS_LIFECYCLE 0 /* Return lifecycle status. */
+#define MLXBF_BOOTCTL_FUSE_STATUS_KEYS 1 /* Return secure boot key status */
+
+/* Additional value to disable the MLXBF_BOOTCTL_SET_SECOND_RESET_ACTION. */
+#define MLXBF_BOOTCTL_NONE 0x7fffffff /* Don't change next boot action */
+
+/* Error values (non-zero). */
+#define MLXBF_BOOTCTL_SMCCC_INVALID_PARAMETERS -2
+
+#endif /* __MLXBF_BOOTCTL_H__ */
--
1.8.3.1