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path: root/drivers/platform/x86/intel/sdsi.c
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Diffstat (limited to 'drivers/platform/x86/intel/sdsi.c')
-rw-r--r--drivers/platform/x86/intel/sdsi.c574
1 files changed, 574 insertions, 0 deletions
diff --git a/drivers/platform/x86/intel/sdsi.c b/drivers/platform/x86/intel/sdsi.c
new file mode 100644
index 000000000000..11d14cc0ff0a
--- /dev/null
+++ b/drivers/platform/x86/intel/sdsi.c
@@ -0,0 +1,574 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Intel Software Defined Silicon driver
+ *
+ * Copyright (c) 2022, Intel Corporation.
+ * All Rights Reserved.
+ *
+ * Author: "David E. Box" <david.e.box@linux.intel.com>
+ */
+
+#include <linux/auxiliary_bus.h>
+#include <linux/bits.h>
+#include <linux/bitfield.h>
+#include <linux/device.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
+#include <linux/uaccess.h>
+
+#include "vsec.h"
+
+#define ACCESS_TYPE_BARID 2
+#define ACCESS_TYPE_LOCAL 3
+
+#define SDSI_MIN_SIZE_DWORDS 276
+#define SDSI_SIZE_CONTROL 8
+#define SDSI_SIZE_MAILBOX 1024
+#define SDSI_SIZE_REGS 72
+#define SDSI_SIZE_CMD sizeof(u64)
+
+/*
+ * Write messages are currently up to the size of the mailbox
+ * while read messages are up to 4 times the size of the
+ * mailbox, sent in packets
+ */
+#define SDSI_SIZE_WRITE_MSG SDSI_SIZE_MAILBOX
+#define SDSI_SIZE_READ_MSG (SDSI_SIZE_MAILBOX * 4)
+
+#define SDSI_ENABLED_FEATURES_OFFSET 16
+#define SDSI_ENABLED BIT(3)
+#define SDSI_SOCKET_ID_OFFSET 64
+#define SDSI_SOCKET_ID GENMASK(3, 0)
+
+#define SDSI_MBOX_CMD_SUCCESS 0x40
+#define SDSI_MBOX_CMD_TIMEOUT 0x80
+
+#define MBOX_TIMEOUT_US 2000
+#define MBOX_TIMEOUT_ACQUIRE_US 1000
+#define MBOX_POLLING_PERIOD_US 100
+#define MBOX_MAX_PACKETS 4
+
+#define MBOX_OWNER_NONE 0x00
+#define MBOX_OWNER_INBAND 0x01
+
+#define CTRL_RUN_BUSY BIT(0)
+#define CTRL_READ_WRITE BIT(1)
+#define CTRL_SOM BIT(2)
+#define CTRL_EOM BIT(3)
+#define CTRL_OWNER GENMASK(5, 4)
+#define CTRL_COMPLETE BIT(6)
+#define CTRL_READY BIT(7)
+#define CTRL_STATUS GENMASK(15, 8)
+#define CTRL_PACKET_SIZE GENMASK(31, 16)
+#define CTRL_MSG_SIZE GENMASK(63, 48)
+
+#define DISC_TABLE_SIZE 12
+#define DT_ACCESS_TYPE GENMASK(3, 0)
+#define DT_SIZE GENMASK(27, 12)
+#define DT_TBIR GENMASK(2, 0)
+#define DT_OFFSET(v) ((v) & GENMASK(31, 3))
+
+enum sdsi_command {
+ SDSI_CMD_PROVISION_AKC = 0x04,
+ SDSI_CMD_PROVISION_CAP = 0x08,
+ SDSI_CMD_READ_STATE = 0x10,
+};
+
+struct sdsi_mbox_info {
+ u64 *payload;
+ u64 *buffer;
+ int size;
+};
+
+struct disc_table {
+ u32 access_info;
+ u32 guid;
+ u32 offset;
+};
+
+struct sdsi_priv {
+ struct mutex mb_lock; /* Mailbox access lock */
+ struct device *dev;
+ void __iomem *control_addr;
+ void __iomem *mbox_addr;
+ void __iomem *regs_addr;
+ u32 guid;
+ bool sdsi_enabled;
+};
+
+/* SDSi mailbox operations must be performed using 64bit mov instructions */
+static __always_inline void
+sdsi_memcpy64_toio(u64 __iomem *to, const u64 *from, size_t count_bytes)
+{
+ size_t count = count_bytes / sizeof(*to);
+ int i;
+
+ for (i = 0; i < count; i++)
+ writeq(from[i], &to[i]);
+}
+
+static __always_inline void
+sdsi_memcpy64_fromio(u64 *to, const u64 __iomem *from, size_t count_bytes)
+{
+ size_t count = count_bytes / sizeof(*to);
+ int i;
+
+ for (i = 0; i < count; i++)
+ to[i] = readq(&from[i]);
+}
+
+static inline void sdsi_complete_transaction(struct sdsi_priv *priv)
+{
+ u64 control = FIELD_PREP(CTRL_COMPLETE, 1);
+
+ lockdep_assert_held(&priv->mb_lock);
+ writeq(control, priv->control_addr);
+}
+
+static int sdsi_status_to_errno(u32 status)
+{
+ switch (status) {
+ case SDSI_MBOX_CMD_SUCCESS:
+ return 0;
+ case SDSI_MBOX_CMD_TIMEOUT:
+ return -ETIMEDOUT;
+ default:
+ return -EIO;
+ }
+}
+
+static int sdsi_mbox_cmd_read(struct sdsi_priv *priv, struct sdsi_mbox_info *info,
+ size_t *data_size)
+{
+ struct device *dev = priv->dev;
+ u32 total, loop, eom, status, message_size;
+ u64 control;
+ int ret;
+
+ lockdep_assert_held(&priv->mb_lock);
+
+ /* Format and send the read command */
+ control = FIELD_PREP(CTRL_EOM, 1) |
+ FIELD_PREP(CTRL_SOM, 1) |
+ FIELD_PREP(CTRL_RUN_BUSY, 1) |
+ FIELD_PREP(CTRL_PACKET_SIZE, info->size);
+ writeq(control, priv->control_addr);
+
+ /* For reads, data sizes that are larger than the mailbox size are read in packets. */
+ total = 0;
+ loop = 0;
+ do {
+ int offset = SDSI_SIZE_MAILBOX * loop;
+ void __iomem *addr = priv->mbox_addr + offset;
+ u64 *buf = info->buffer + offset / SDSI_SIZE_CMD;
+ u32 packet_size;
+
+ /* Poll on ready bit */
+ ret = readq_poll_timeout(priv->control_addr, control, control & CTRL_READY,
+ MBOX_POLLING_PERIOD_US, MBOX_TIMEOUT_US);
+ if (ret)
+ break;
+
+ eom = FIELD_GET(CTRL_EOM, control);
+ status = FIELD_GET(CTRL_STATUS, control);
+ packet_size = FIELD_GET(CTRL_PACKET_SIZE, control);
+ message_size = FIELD_GET(CTRL_MSG_SIZE, control);
+
+ ret = sdsi_status_to_errno(status);
+ if (ret)
+ break;
+
+ /* Only the last packet can be less than the mailbox size. */
+ if (!eom && packet_size != SDSI_SIZE_MAILBOX) {
+ dev_err(dev, "Invalid packet size\n");
+ ret = -EPROTO;
+ break;
+ }
+
+ if (packet_size > SDSI_SIZE_MAILBOX) {
+ dev_err(dev, "Packet size too large\n");
+ ret = -EPROTO;
+ break;
+ }
+
+ sdsi_memcpy64_fromio(buf, addr, round_up(packet_size, SDSI_SIZE_CMD));
+
+ total += packet_size;
+
+ sdsi_complete_transaction(priv);
+ } while (!eom && ++loop < MBOX_MAX_PACKETS);
+
+ if (ret) {
+ sdsi_complete_transaction(priv);
+ return ret;
+ }
+
+ if (!eom) {
+ dev_err(dev, "Exceeded read attempts\n");
+ return -EPROTO;
+ }
+
+ /* Message size check is only valid for multi-packet transfers */
+ if (loop && total != message_size)
+ dev_warn(dev, "Read count %u differs from expected count %u\n",
+ total, message_size);
+
+ *data_size = total;
+
+ return 0;
+}
+
+static int sdsi_mbox_cmd_write(struct sdsi_priv *priv, struct sdsi_mbox_info *info)
+{
+ u64 control;
+ u32 status;
+ int ret;
+
+ lockdep_assert_held(&priv->mb_lock);
+
+ /* Write rest of the payload */
+ sdsi_memcpy64_toio(priv->mbox_addr + SDSI_SIZE_CMD, info->payload + 1,
+ info->size - SDSI_SIZE_CMD);
+
+ /* Format and send the write command */
+ control = FIELD_PREP(CTRL_EOM, 1) |
+ FIELD_PREP(CTRL_SOM, 1) |
+ FIELD_PREP(CTRL_RUN_BUSY, 1) |
+ FIELD_PREP(CTRL_READ_WRITE, 1) |
+ FIELD_PREP(CTRL_PACKET_SIZE, info->size);
+ writeq(control, priv->control_addr);
+
+ /* Poll on run_busy bit */
+ ret = readq_poll_timeout(priv->control_addr, control, !(control & CTRL_RUN_BUSY),
+ MBOX_POLLING_PERIOD_US, MBOX_TIMEOUT_US);
+
+ if (ret)
+ goto release_mbox;
+
+ status = FIELD_GET(CTRL_STATUS, control);
+ ret = sdsi_status_to_errno(status);
+
+release_mbox:
+ sdsi_complete_transaction(priv);
+
+ return ret;
+}
+
+static int sdsi_mbox_acquire(struct sdsi_priv *priv, struct sdsi_mbox_info *info)
+{
+ u64 control;
+ u32 owner;
+ int ret;
+
+ lockdep_assert_held(&priv->mb_lock);
+
+ /* Check mailbox is available */
+ control = readq(priv->control_addr);
+ owner = FIELD_GET(CTRL_OWNER, control);
+ if (owner != MBOX_OWNER_NONE)
+ return -EBUSY;
+
+ /* Write first qword of payload */
+ writeq(info->payload[0], priv->mbox_addr);
+
+ /* Check for ownership */
+ ret = readq_poll_timeout(priv->control_addr, control,
+ FIELD_GET(CTRL_OWNER, control) & MBOX_OWNER_INBAND,
+ MBOX_POLLING_PERIOD_US, MBOX_TIMEOUT_ACQUIRE_US);
+
+ return ret;
+}
+
+static int sdsi_mbox_write(struct sdsi_priv *priv, struct sdsi_mbox_info *info)
+{
+ int ret;
+
+ lockdep_assert_held(&priv->mb_lock);
+
+ ret = sdsi_mbox_acquire(priv, info);
+ if (ret)
+ return ret;
+
+ return sdsi_mbox_cmd_write(priv, info);
+}
+
+static int sdsi_mbox_read(struct sdsi_priv *priv, struct sdsi_mbox_info *info, size_t *data_size)
+{
+ int ret;
+
+ lockdep_assert_held(&priv->mb_lock);
+
+ ret = sdsi_mbox_acquire(priv, info);
+ if (ret)
+ return ret;
+
+ return sdsi_mbox_cmd_read(priv, info, data_size);
+}
+
+static ssize_t sdsi_provision(struct sdsi_priv *priv, char *buf, size_t count,
+ enum sdsi_command command)
+{
+ struct sdsi_mbox_info info;
+ int ret;
+
+ if (!priv->sdsi_enabled)
+ return -EPERM;
+
+ if (count > (SDSI_SIZE_WRITE_MSG - SDSI_SIZE_CMD))
+ return -EOVERFLOW;
+
+ /* Qword aligned message + command qword */
+ info.size = round_up(count, SDSI_SIZE_CMD) + SDSI_SIZE_CMD;
+
+ info.payload = kzalloc(info.size, GFP_KERNEL);
+ if (!info.payload)
+ return -ENOMEM;
+
+ /* Copy message to payload buffer */
+ memcpy(info.payload, buf, count);
+
+ /* Command is last qword of payload buffer */
+ info.payload[(info.size - SDSI_SIZE_CMD) / SDSI_SIZE_CMD] = command;
+
+ ret = mutex_lock_interruptible(&priv->mb_lock);
+ if (ret)
+ goto free_payload;
+ ret = sdsi_mbox_write(priv, &info);
+ mutex_unlock(&priv->mb_lock);
+
+free_payload:
+ kfree(info.payload);
+
+ if (ret)
+ return ret;
+
+ return count;
+}
+
+static ssize_t provision_akc_write(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *attr, char *buf, loff_t off,
+ size_t count)
+{
+ struct device *dev = kobj_to_dev(kobj);
+ struct sdsi_priv *priv = dev_get_drvdata(dev);
+
+ if (off)
+ return -ESPIPE;
+
+ return sdsi_provision(priv, buf, count, SDSI_CMD_PROVISION_AKC);
+}
+static BIN_ATTR_WO(provision_akc, SDSI_SIZE_WRITE_MSG);
+
+static ssize_t provision_cap_write(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *attr, char *buf, loff_t off,
+ size_t count)
+{
+ struct device *dev = kobj_to_dev(kobj);
+ struct sdsi_priv *priv = dev_get_drvdata(dev);
+
+ if (off)
+ return -ESPIPE;
+
+ return sdsi_provision(priv, buf, count, SDSI_CMD_PROVISION_CAP);
+}
+static BIN_ATTR_WO(provision_cap, SDSI_SIZE_WRITE_MSG);
+
+static long state_certificate_read(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *attr, char *buf, loff_t off,
+ size_t count)
+{
+ struct device *dev = kobj_to_dev(kobj);
+ struct sdsi_priv *priv = dev_get_drvdata(dev);
+ u64 command = SDSI_CMD_READ_STATE;
+ struct sdsi_mbox_info info;
+ size_t size;
+ int ret;
+
+ if (!priv->sdsi_enabled)
+ return -EPERM;
+
+ if (off)
+ return 0;
+
+ /* Buffer for return data */
+ info.buffer = kmalloc(SDSI_SIZE_READ_MSG, GFP_KERNEL);
+ if (!info.buffer)
+ return -ENOMEM;
+
+ info.payload = &command;
+ info.size = sizeof(command);
+
+ ret = mutex_lock_interruptible(&priv->mb_lock);
+ if (ret)
+ goto free_buffer;
+ ret = sdsi_mbox_read(priv, &info, &size);
+ mutex_unlock(&priv->mb_lock);
+ if (ret < 0)
+ goto free_buffer;
+
+ if (size > count)
+ size = count;
+
+ memcpy(buf, info.buffer, size);
+
+free_buffer:
+ kfree(info.buffer);
+
+ if (ret)
+ return ret;
+
+ return size;
+}
+static BIN_ATTR(state_certificate, 0400, state_certificate_read, NULL, SDSI_SIZE_READ_MSG);
+
+static ssize_t registers_read(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *attr, char *buf, loff_t off,
+ size_t count)
+{
+ struct device *dev = kobj_to_dev(kobj);
+ struct sdsi_priv *priv = dev_get_drvdata(dev);
+ void __iomem *addr = priv->regs_addr;
+
+ memcpy_fromio(buf, addr + off, count);
+
+ return count;
+}
+static BIN_ATTR(registers, 0400, registers_read, NULL, SDSI_SIZE_REGS);
+
+static struct bin_attribute *sdsi_bin_attrs[] = {
+ &bin_attr_registers,
+ &bin_attr_state_certificate,
+ &bin_attr_provision_akc,
+ &bin_attr_provision_cap,
+ NULL
+};
+
+static ssize_t guid_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct sdsi_priv *priv = dev_get_drvdata(dev);
+
+ return sysfs_emit(buf, "0x%x\n", priv->guid);
+}
+static DEVICE_ATTR_RO(guid);
+
+static struct attribute *sdsi_attrs[] = {
+ &dev_attr_guid.attr,
+ NULL
+};
+
+static const struct attribute_group sdsi_group = {
+ .attrs = sdsi_attrs,
+ .bin_attrs = sdsi_bin_attrs,
+};
+__ATTRIBUTE_GROUPS(sdsi);
+
+static int sdsi_map_mbox_registers(struct sdsi_priv *priv, struct pci_dev *parent,
+ struct disc_table *disc_table, struct resource *disc_res)
+{
+ u32 access_type = FIELD_GET(DT_ACCESS_TYPE, disc_table->access_info);
+ u32 size = FIELD_GET(DT_SIZE, disc_table->access_info);
+ u32 tbir = FIELD_GET(DT_TBIR, disc_table->offset);
+ u32 offset = DT_OFFSET(disc_table->offset);
+ u32 features_offset;
+ struct resource res = {};
+
+ /* Starting location of SDSi MMIO region based on access type */
+ switch (access_type) {
+ case ACCESS_TYPE_LOCAL:
+ if (tbir) {
+ dev_err(priv->dev, "Unsupported BAR index %u for access type %u\n",
+ tbir, access_type);
+ return -EINVAL;
+ }
+
+ /*
+ * For access_type LOCAL, the base address is as follows:
+ * base address = end of discovery region + base offset + 1
+ */
+ res.start = disc_res->end + offset + 1;
+ break;
+
+ case ACCESS_TYPE_BARID:
+ res.start = pci_resource_start(parent, tbir) + offset;
+ break;
+
+ default:
+ dev_err(priv->dev, "Unrecognized access_type %u\n", access_type);
+ return -EINVAL;
+ }
+
+ res.end = res.start + size * sizeof(u32) - 1;
+ res.flags = IORESOURCE_MEM;
+
+ priv->control_addr = devm_ioremap_resource(priv->dev, &res);
+ if (IS_ERR(priv->control_addr))
+ return PTR_ERR(priv->control_addr);
+
+ priv->mbox_addr = priv->control_addr + SDSI_SIZE_CONTROL;
+ priv->regs_addr = priv->mbox_addr + SDSI_SIZE_MAILBOX;
+
+ features_offset = readq(priv->regs_addr + SDSI_ENABLED_FEATURES_OFFSET);
+ priv->sdsi_enabled = !!(features_offset & SDSI_ENABLED);
+
+ return 0;
+}
+
+static int sdsi_probe(struct auxiliary_device *auxdev, const struct auxiliary_device_id *id)
+{
+ struct intel_vsec_device *intel_cap_dev = auxdev_to_ivdev(auxdev);
+ struct disc_table disc_table;
+ struct resource *disc_res;
+ void __iomem *disc_addr;
+ struct sdsi_priv *priv;
+ int ret;
+
+ priv = devm_kzalloc(&auxdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->dev = &auxdev->dev;
+ mutex_init(&priv->mb_lock);
+ auxiliary_set_drvdata(auxdev, priv);
+
+ /* Get the SDSi discovery table */
+ disc_res = &intel_cap_dev->resource[0];
+ disc_addr = devm_ioremap_resource(&auxdev->dev, disc_res);
+ if (IS_ERR(disc_addr))
+ return PTR_ERR(disc_addr);
+
+ memcpy_fromio(&disc_table, disc_addr, DISC_TABLE_SIZE);
+
+ priv->guid = disc_table.guid;
+
+ /* Map the SDSi mailbox registers */
+ ret = sdsi_map_mbox_registers(priv, intel_cap_dev->pcidev, &disc_table, disc_res);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static const struct auxiliary_device_id sdsi_aux_id_table[] = {
+ { .name = "intel_vsec.sdsi" },
+ {}
+};
+MODULE_DEVICE_TABLE(auxiliary, sdsi_aux_id_table);
+
+static struct auxiliary_driver sdsi_aux_driver = {
+ .driver = {
+ .dev_groups = sdsi_groups,
+ },
+ .id_table = sdsi_aux_id_table,
+ .probe = sdsi_probe,
+ /* No remove. All resources are handled under devm */
+};
+module_auxiliary_driver(sdsi_aux_driver);
+
+MODULE_AUTHOR("David E. Box <david.e.box@linux.intel.com>");
+MODULE_DESCRIPTION("Intel Software Defined Silicon driver");
+MODULE_LICENSE("GPL");
generated by cgit (git 2.34.1) at 2024-06-08 17:45:27 +0000