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Diffstat (limited to 'drivers/cxl/core/mbox.c')
-rw-r--r--drivers/cxl/core/mbox.c787
1 files changed, 787 insertions, 0 deletions
diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
new file mode 100644
index 000000000000..576796a5d9f3
--- /dev/null
+++ b/drivers/cxl/core/mbox.c
@@ -0,0 +1,787 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright(c) 2020 Intel Corporation. All rights reserved. */
+#include <linux/io-64-nonatomic-lo-hi.h>
+#include <linux/security.h>
+#include <linux/debugfs.h>
+#include <linux/mutex.h>
+#include <cxlmem.h>
+#include <cxl.h>
+
+#include "core.h"
+
+static bool cxl_raw_allow_all;
+
+/**
+ * DOC: cxl mbox
+ *
+ * Core implementation of the CXL 2.0 Type-3 Memory Device Mailbox. The
+ * implementation is used by the cxl_pci driver to initialize the device
+ * and implement the cxl_mem.h IOCTL UAPI. It also implements the
+ * backend of the cxl_pmem_ctl() transport for LIBNVDIMM.
+ */
+
+#define cxl_for_each_cmd(cmd) \
+ for ((cmd) = &cxl_mem_commands[0]; \
+ ((cmd) - cxl_mem_commands) < ARRAY_SIZE(cxl_mem_commands); (cmd)++)
+
+#define CXL_CMD(_id, sin, sout, _flags) \
+ [CXL_MEM_COMMAND_ID_##_id] = { \
+ .info = { \
+ .id = CXL_MEM_COMMAND_ID_##_id, \
+ .size_in = sin, \
+ .size_out = sout, \
+ }, \
+ .opcode = CXL_MBOX_OP_##_id, \
+ .flags = _flags, \
+ }
+
+/*
+ * This table defines the supported mailbox commands for the driver. This table
+ * is made up of a UAPI structure. Non-negative values as parameters in the
+ * table will be validated against the user's input. For example, if size_in is
+ * 0, and the user passed in 1, it is an error.
+ */
+static struct cxl_mem_command cxl_mem_commands[CXL_MEM_COMMAND_ID_MAX] = {
+ CXL_CMD(IDENTIFY, 0, 0x43, CXL_CMD_FLAG_FORCE_ENABLE),
+#ifdef CONFIG_CXL_MEM_RAW_COMMANDS
+ CXL_CMD(RAW, ~0, ~0, 0),
+#endif
+ CXL_CMD(GET_SUPPORTED_LOGS, 0, ~0, CXL_CMD_FLAG_FORCE_ENABLE),
+ CXL_CMD(GET_FW_INFO, 0, 0x50, 0),
+ CXL_CMD(GET_PARTITION_INFO, 0, 0x20, 0),
+ CXL_CMD(GET_LSA, 0x8, ~0, 0),
+ CXL_CMD(GET_HEALTH_INFO, 0, 0x12, 0),
+ CXL_CMD(GET_LOG, 0x18, ~0, CXL_CMD_FLAG_FORCE_ENABLE),
+ CXL_CMD(SET_PARTITION_INFO, 0x0a, 0, 0),
+ CXL_CMD(SET_LSA, ~0, 0, 0),
+ CXL_CMD(GET_ALERT_CONFIG, 0, 0x10, 0),
+ CXL_CMD(SET_ALERT_CONFIG, 0xc, 0, 0),
+ CXL_CMD(GET_SHUTDOWN_STATE, 0, 0x1, 0),
+ CXL_CMD(SET_SHUTDOWN_STATE, 0x1, 0, 0),
+ CXL_CMD(GET_POISON, 0x10, ~0, 0),
+ CXL_CMD(INJECT_POISON, 0x8, 0, 0),
+ CXL_CMD(CLEAR_POISON, 0x48, 0, 0),
+ CXL_CMD(GET_SCAN_MEDIA_CAPS, 0x10, 0x4, 0),
+ CXL_CMD(SCAN_MEDIA, 0x11, 0, 0),
+ CXL_CMD(GET_SCAN_MEDIA, 0, ~0, 0),
+};
+
+/*
+ * Commands that RAW doesn't permit. The rationale for each:
+ *
+ * CXL_MBOX_OP_ACTIVATE_FW: Firmware activation requires adjustment /
+ * coordination of transaction timeout values at the root bridge level.
+ *
+ * CXL_MBOX_OP_SET_PARTITION_INFO: The device memory map may change live
+ * and needs to be coordinated with HDM updates.
+ *
+ * CXL_MBOX_OP_SET_LSA: The label storage area may be cached by the
+ * driver and any writes from userspace invalidates those contents.
+ *
+ * CXL_MBOX_OP_SET_SHUTDOWN_STATE: Set shutdown state assumes no writes
+ * to the device after it is marked clean, userspace can not make that
+ * assertion.
+ *
+ * CXL_MBOX_OP_[GET_]SCAN_MEDIA: The kernel provides a native error list that
+ * is kept up to date with patrol notifications and error management.
+ */
+static u16 cxl_disabled_raw_commands[] = {
+ CXL_MBOX_OP_ACTIVATE_FW,
+ CXL_MBOX_OP_SET_PARTITION_INFO,
+ CXL_MBOX_OP_SET_LSA,
+ CXL_MBOX_OP_SET_SHUTDOWN_STATE,
+ CXL_MBOX_OP_SCAN_MEDIA,
+ CXL_MBOX_OP_GET_SCAN_MEDIA,
+};
+
+/*
+ * Command sets that RAW doesn't permit. All opcodes in this set are
+ * disabled because they pass plain text security payloads over the
+ * user/kernel boundary. This functionality is intended to be wrapped
+ * behind the keys ABI which allows for encrypted payloads in the UAPI
+ */
+static u8 security_command_sets[] = {
+ 0x44, /* Sanitize */
+ 0x45, /* Persistent Memory Data-at-rest Security */
+ 0x46, /* Security Passthrough */
+};
+
+static bool cxl_is_security_command(u16 opcode)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(security_command_sets); i++)
+ if (security_command_sets[i] == (opcode >> 8))
+ return true;
+ return false;
+}
+
+static struct cxl_mem_command *cxl_mem_find_command(u16 opcode)
+{
+ struct cxl_mem_command *c;
+
+ cxl_for_each_cmd(c)
+ if (c->opcode == opcode)
+ return c;
+
+ return NULL;
+}
+
+/**
+ * cxl_mem_mbox_send_cmd() - Send a mailbox command to a memory device.
+ * @cxlm: The CXL memory device to communicate with.
+ * @opcode: Opcode for the mailbox command.
+ * @in: The input payload for the mailbox command.
+ * @in_size: The length of the input payload
+ * @out: Caller allocated buffer for the output.
+ * @out_size: Expected size of output.
+ *
+ * Context: Any context. Will acquire and release mbox_mutex.
+ * Return:
+ * * %>=0 - Number of bytes returned in @out.
+ * * %-E2BIG - Payload is too large for hardware.
+ * * %-EBUSY - Couldn't acquire exclusive mailbox access.
+ * * %-EFAULT - Hardware error occurred.
+ * * %-ENXIO - Command completed, but device reported an error.
+ * * %-EIO - Unexpected output size.
+ *
+ * Mailbox commands may execute successfully yet the device itself reported an
+ * error. While this distinction can be useful for commands from userspace, the
+ * kernel will only be able to use results when both are successful.
+ *
+ * See __cxl_mem_mbox_send_cmd()
+ */
+int cxl_mem_mbox_send_cmd(struct cxl_mem *cxlm, u16 opcode, void *in,
+ size_t in_size, void *out, size_t out_size)
+{
+ const struct cxl_mem_command *cmd = cxl_mem_find_command(opcode);
+ struct cxl_mbox_cmd mbox_cmd = {
+ .opcode = opcode,
+ .payload_in = in,
+ .size_in = in_size,
+ .size_out = out_size,
+ .payload_out = out,
+ };
+ int rc;
+
+ if (out_size > cxlm->payload_size)
+ return -E2BIG;
+
+ rc = cxlm->mbox_send(cxlm, &mbox_cmd);
+ if (rc)
+ return rc;
+
+ /* TODO: Map return code to proper kernel style errno */
+ if (mbox_cmd.return_code != CXL_MBOX_SUCCESS)
+ return -ENXIO;
+
+ /*
+ * Variable sized commands can't be validated and so it's up to the
+ * caller to do that if they wish.
+ */
+ if (cmd->info.size_out >= 0 && mbox_cmd.size_out != out_size)
+ return -EIO;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(cxl_mem_mbox_send_cmd);
+
+static bool cxl_mem_raw_command_allowed(u16 opcode)
+{
+ int i;
+
+ if (!IS_ENABLED(CONFIG_CXL_MEM_RAW_COMMANDS))
+ return false;
+
+ if (security_locked_down(LOCKDOWN_PCI_ACCESS))
+ return false;
+
+ if (cxl_raw_allow_all)
+ return true;
+
+ if (cxl_is_security_command(opcode))
+ return false;
+
+ for (i = 0; i < ARRAY_SIZE(cxl_disabled_raw_commands); i++)
+ if (cxl_disabled_raw_commands[i] == opcode)
+ return false;
+
+ return true;
+}
+
+/**
+ * cxl_validate_cmd_from_user() - Check fields for CXL_MEM_SEND_COMMAND.
+ * @cxlm: &struct cxl_mem device whose mailbox will be used.
+ * @send_cmd: &struct cxl_send_command copied in from userspace.
+ * @out_cmd: Sanitized and populated &struct cxl_mem_command.
+ *
+ * Return:
+ * * %0 - @out_cmd is ready to send.
+ * * %-ENOTTY - Invalid command specified.
+ * * %-EINVAL - Reserved fields or invalid values were used.
+ * * %-ENOMEM - Input or output buffer wasn't sized properly.
+ * * %-EPERM - Attempted to use a protected command.
+ * * %-EBUSY - Kernel has claimed exclusive access to this opcode
+ *
+ * The result of this command is a fully validated command in @out_cmd that is
+ * safe to send to the hardware.
+ *
+ * See handle_mailbox_cmd_from_user()
+ */
+static int cxl_validate_cmd_from_user(struct cxl_mem *cxlm,
+ const struct cxl_send_command *send_cmd,
+ struct cxl_mem_command *out_cmd)
+{
+ const struct cxl_command_info *info;
+ struct cxl_mem_command *c;
+
+ if (send_cmd->id == 0 || send_cmd->id >= CXL_MEM_COMMAND_ID_MAX)
+ return -ENOTTY;
+
+ /*
+ * The user can never specify an input payload larger than what hardware
+ * supports, but output can be arbitrarily large (simply write out as
+ * much data as the hardware provides).
+ */
+ if (send_cmd->in.size > cxlm->payload_size)
+ return -EINVAL;
+
+ /*
+ * Checks are bypassed for raw commands but a WARN/taint will occur
+ * later in the callchain
+ */
+ if (send_cmd->id == CXL_MEM_COMMAND_ID_RAW) {
+ const struct cxl_mem_command temp = {
+ .info = {
+ .id = CXL_MEM_COMMAND_ID_RAW,
+ .flags = 0,
+ .size_in = send_cmd->in.size,
+ .size_out = send_cmd->out.size,
+ },
+ .opcode = send_cmd->raw.opcode
+ };
+
+ if (send_cmd->raw.rsvd)
+ return -EINVAL;
+
+ /*
+ * Unlike supported commands, the output size of RAW commands
+ * gets passed along without further checking, so it must be
+ * validated here.
+ */
+ if (send_cmd->out.size > cxlm->payload_size)
+ return -EINVAL;
+
+ if (!cxl_mem_raw_command_allowed(send_cmd->raw.opcode))
+ return -EPERM;
+
+ memcpy(out_cmd, &temp, sizeof(temp));
+
+ return 0;
+ }
+
+ if (send_cmd->flags & ~CXL_MEM_COMMAND_FLAG_MASK)
+ return -EINVAL;
+
+ if (send_cmd->rsvd)
+ return -EINVAL;
+
+ if (send_cmd->in.rsvd || send_cmd->out.rsvd)
+ return -EINVAL;
+
+ /* Convert user's command into the internal representation */
+ c = &cxl_mem_commands[send_cmd->id];
+ info = &c->info;
+
+ /* Check that the command is enabled for hardware */
+ if (!test_bit(info->id, cxlm->enabled_cmds))
+ return -ENOTTY;
+
+ /* Check that the command is not claimed for exclusive kernel use */
+ if (test_bit(info->id, cxlm->exclusive_cmds))
+ return -EBUSY;
+
+ /* Check the input buffer is the expected size */
+ if (info->size_in >= 0 && info->size_in != send_cmd->in.size)
+ return -ENOMEM;
+
+ /* Check the output buffer is at least large enough */
+ if (info->size_out >= 0 && send_cmd->out.size < info->size_out)
+ return -ENOMEM;
+
+ memcpy(out_cmd, c, sizeof(*c));
+ out_cmd->info.size_in = send_cmd->in.size;
+ /*
+ * XXX: out_cmd->info.size_out will be controlled by the driver, and the
+ * specified number of bytes @send_cmd->out.size will be copied back out
+ * to userspace.
+ */
+
+ return 0;
+}
+
+int cxl_query_cmd(struct cxl_memdev *cxlmd,
+ struct cxl_mem_query_commands __user *q)
+{
+ struct device *dev = &cxlmd->dev;
+ struct cxl_mem_command *cmd;
+ u32 n_commands;
+ int j = 0;
+
+ dev_dbg(dev, "Query IOCTL\n");
+
+ if (get_user(n_commands, &q->n_commands))
+ return -EFAULT;
+
+ /* returns the total number if 0 elements are requested. */
+ if (n_commands == 0)
+ return put_user(ARRAY_SIZE(cxl_mem_commands), &q->n_commands);
+
+ /*
+ * otherwise, return max(n_commands, total commands) cxl_command_info
+ * structures.
+ */
+ cxl_for_each_cmd(cmd) {
+ const struct cxl_command_info *info = &cmd->info;
+
+ if (copy_to_user(&q->commands[j++], info, sizeof(*info)))
+ return -EFAULT;
+
+ if (j == n_commands)
+ break;
+ }
+
+ return 0;
+}
+
+/**
+ * handle_mailbox_cmd_from_user() - Dispatch a mailbox command for userspace.
+ * @cxlm: The CXL memory device to communicate with.
+ * @cmd: The validated command.
+ * @in_payload: Pointer to userspace's input payload.
+ * @out_payload: Pointer to userspace's output payload.
+ * @size_out: (Input) Max payload size to copy out.
+ * (Output) Payload size hardware generated.
+ * @retval: Hardware generated return code from the operation.
+ *
+ * Return:
+ * * %0 - Mailbox transaction succeeded. This implies the mailbox
+ * protocol completed successfully not that the operation itself
+ * was successful.
+ * * %-ENOMEM - Couldn't allocate a bounce buffer.
+ * * %-EFAULT - Something happened with copy_to/from_user.
+ * * %-EINTR - Mailbox acquisition interrupted.
+ * * %-EXXX - Transaction level failures.
+ *
+ * Creates the appropriate mailbox command and dispatches it on behalf of a
+ * userspace request. The input and output payloads are copied between
+ * userspace.
+ *
+ * See cxl_send_cmd().
+ */
+static int handle_mailbox_cmd_from_user(struct cxl_mem *cxlm,
+ const struct cxl_mem_command *cmd,
+ u64 in_payload, u64 out_payload,
+ s32 *size_out, u32 *retval)
+{
+ struct device *dev = cxlm->dev;
+ struct cxl_mbox_cmd mbox_cmd = {
+ .opcode = cmd->opcode,
+ .size_in = cmd->info.size_in,
+ .size_out = cmd->info.size_out,
+ };
+ int rc;
+
+ if (cmd->info.size_out) {
+ mbox_cmd.payload_out = kvzalloc(cmd->info.size_out, GFP_KERNEL);
+ if (!mbox_cmd.payload_out)
+ return -ENOMEM;
+ }
+
+ if (cmd->info.size_in) {
+ mbox_cmd.payload_in = vmemdup_user(u64_to_user_ptr(in_payload),
+ cmd->info.size_in);
+ if (IS_ERR(mbox_cmd.payload_in)) {
+ kvfree(mbox_cmd.payload_out);
+ return PTR_ERR(mbox_cmd.payload_in);
+ }
+ }
+
+ dev_dbg(dev,
+ "Submitting %s command for user\n"
+ "\topcode: %x\n"
+ "\tsize: %ub\n",
+ cxl_command_names[cmd->info.id].name, mbox_cmd.opcode,
+ cmd->info.size_in);
+
+ dev_WARN_ONCE(dev, cmd->info.id == CXL_MEM_COMMAND_ID_RAW,
+ "raw command path used\n");
+
+ rc = cxlm->mbox_send(cxlm, &mbox_cmd);
+ if (rc)
+ goto out;
+
+ /*
+ * @size_out contains the max size that's allowed to be written back out
+ * to userspace. While the payload may have written more output than
+ * this it will have to be ignored.
+ */
+ if (mbox_cmd.size_out) {
+ dev_WARN_ONCE(dev, mbox_cmd.size_out > *size_out,
+ "Invalid return size\n");
+ if (copy_to_user(u64_to_user_ptr(out_payload),
+ mbox_cmd.payload_out, mbox_cmd.size_out)) {
+ rc = -EFAULT;
+ goto out;
+ }
+ }
+
+ *size_out = mbox_cmd.size_out;
+ *retval = mbox_cmd.return_code;
+
+out:
+ kvfree(mbox_cmd.payload_in);
+ kvfree(mbox_cmd.payload_out);
+ return rc;
+}
+
+int cxl_send_cmd(struct cxl_memdev *cxlmd, struct cxl_send_command __user *s)
+{
+ struct cxl_mem *cxlm = cxlmd->cxlm;
+ struct device *dev = &cxlmd->dev;
+ struct cxl_send_command send;
+ struct cxl_mem_command c;
+ int rc;
+
+ dev_dbg(dev, "Send IOCTL\n");
+
+ if (copy_from_user(&send, s, sizeof(send)))
+ return -EFAULT;
+
+ rc = cxl_validate_cmd_from_user(cxlmd->cxlm, &send, &c);
+ if (rc)
+ return rc;
+
+ /* Prepare to handle a full payload for variable sized output */
+ if (c.info.size_out < 0)
+ c.info.size_out = cxlm->payload_size;
+
+ rc = handle_mailbox_cmd_from_user(cxlm, &c, send.in.payload,
+ send.out.payload, &send.out.size,
+ &send.retval);
+ if (rc)
+ return rc;
+
+ if (copy_to_user(s, &send, sizeof(send)))
+ return -EFAULT;
+
+ return 0;
+}
+
+static int cxl_xfer_log(struct cxl_mem *cxlm, uuid_t *uuid, u32 size, u8 *out)
+{
+ u32 remaining = size;
+ u32 offset = 0;
+
+ while (remaining) {
+ u32 xfer_size = min_t(u32, remaining, cxlm->payload_size);
+ struct cxl_mbox_get_log log = {
+ .uuid = *uuid,
+ .offset = cpu_to_le32(offset),
+ .length = cpu_to_le32(xfer_size)
+ };
+ int rc;
+
+ rc = cxl_mem_mbox_send_cmd(cxlm, CXL_MBOX_OP_GET_LOG, &log,
+ sizeof(log), out, xfer_size);
+ if (rc < 0)
+ return rc;
+
+ out += xfer_size;
+ remaining -= xfer_size;
+ offset += xfer_size;
+ }
+
+ return 0;
+}
+
+/**
+ * cxl_walk_cel() - Walk through the Command Effects Log.
+ * @cxlm: Device.
+ * @size: Length of the Command Effects Log.
+ * @cel: CEL
+ *
+ * Iterate over each entry in the CEL and determine if the driver supports the
+ * command. If so, the command is enabled for the device and can be used later.
+ */
+static void cxl_walk_cel(struct cxl_mem *cxlm, size_t size, u8 *cel)
+{
+ struct cxl_cel_entry *cel_entry;
+ const int cel_entries = size / sizeof(*cel_entry);
+ int i;
+
+ cel_entry = (struct cxl_cel_entry *) cel;
+
+ for (i = 0; i < cel_entries; i++) {
+ u16 opcode = le16_to_cpu(cel_entry[i].opcode);
+ struct cxl_mem_command *cmd = cxl_mem_find_command(opcode);
+
+ if (!cmd) {
+ dev_dbg(cxlm->dev,
+ "Opcode 0x%04x unsupported by driver", opcode);
+ continue;
+ }
+
+ set_bit(cmd->info.id, cxlm->enabled_cmds);
+ }
+}
+
+static struct cxl_mbox_get_supported_logs *cxl_get_gsl(struct cxl_mem *cxlm)
+{
+ struct cxl_mbox_get_supported_logs *ret;
+ int rc;
+
+ ret = kvmalloc(cxlm->payload_size, GFP_KERNEL);
+ if (!ret)
+ return ERR_PTR(-ENOMEM);
+
+ rc = cxl_mem_mbox_send_cmd(cxlm, CXL_MBOX_OP_GET_SUPPORTED_LOGS, NULL,
+ 0, ret, cxlm->payload_size);
+ if (rc < 0) {
+ kvfree(ret);
+ return ERR_PTR(rc);
+ }
+
+ return ret;
+}
+
+enum {
+ CEL_UUID,
+ VENDOR_DEBUG_UUID,
+};
+
+/* See CXL 2.0 Table 170. Get Log Input Payload */
+static const uuid_t log_uuid[] = {
+ [CEL_UUID] = DEFINE_CXL_CEL_UUID,
+ [VENDOR_DEBUG_UUID] = DEFINE_CXL_VENDOR_DEBUG_UUID,
+};
+
+/**
+ * cxl_mem_enumerate_cmds() - Enumerate commands for a device.
+ * @cxlm: The device.
+ *
+ * Returns 0 if enumerate completed successfully.
+ *
+ * CXL devices have optional support for certain commands. This function will
+ * determine the set of supported commands for the hardware and update the
+ * enabled_cmds bitmap in the @cxlm.
+ */
+int cxl_mem_enumerate_cmds(struct cxl_mem *cxlm)
+{
+ struct cxl_mbox_get_supported_logs *gsl;
+ struct device *dev = cxlm->dev;
+ struct cxl_mem_command *cmd;
+ int i, rc;
+
+ gsl = cxl_get_gsl(cxlm);
+ if (IS_ERR(gsl))
+ return PTR_ERR(gsl);
+
+ rc = -ENOENT;
+ for (i = 0; i < le16_to_cpu(gsl->entries); i++) {
+ u32 size = le32_to_cpu(gsl->entry[i].size);
+ uuid_t uuid = gsl->entry[i].uuid;
+ u8 *log;
+
+ dev_dbg(dev, "Found LOG type %pU of size %d", &uuid, size);
+
+ if (!uuid_equal(&uuid, &log_uuid[CEL_UUID]))
+ continue;
+
+ log = kvmalloc(size, GFP_KERNEL);
+ if (!log) {
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ rc = cxl_xfer_log(cxlm, &uuid, size, log);
+ if (rc) {
+ kvfree(log);
+ goto out;
+ }
+
+ cxl_walk_cel(cxlm, size, log);
+ kvfree(log);
+
+ /* In case CEL was bogus, enable some default commands. */
+ cxl_for_each_cmd(cmd)
+ if (cmd->flags & CXL_CMD_FLAG_FORCE_ENABLE)
+ set_bit(cmd->info.id, cxlm->enabled_cmds);
+
+ /* Found the required CEL */
+ rc = 0;
+ }
+
+out:
+ kvfree(gsl);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(cxl_mem_enumerate_cmds);
+
+/**
+ * cxl_mem_get_partition_info - Get partition info
+ * @cxlm: cxl_mem instance to update partition info
+ *
+ * Retrieve the current partition info for the device specified. The active
+ * values are the current capacity in bytes. If not 0, the 'next' values are
+ * the pending values, in bytes, which take affect on next cold reset.
+ *
+ * Return: 0 if no error: or the result of the mailbox command.
+ *
+ * See CXL @8.2.9.5.2.1 Get Partition Info
+ */
+static int cxl_mem_get_partition_info(struct cxl_mem *cxlm)
+{
+ struct cxl_mbox_get_partition_info {
+ __le64 active_volatile_cap;
+ __le64 active_persistent_cap;
+ __le64 next_volatile_cap;
+ __le64 next_persistent_cap;
+ } __packed pi;
+ int rc;
+
+ rc = cxl_mem_mbox_send_cmd(cxlm, CXL_MBOX_OP_GET_PARTITION_INFO,
+ NULL, 0, &pi, sizeof(pi));
+
+ if (rc)
+ return rc;
+
+ cxlm->active_volatile_bytes =
+ le64_to_cpu(pi.active_volatile_cap) * CXL_CAPACITY_MULTIPLIER;
+ cxlm->active_persistent_bytes =
+ le64_to_cpu(pi.active_persistent_cap) * CXL_CAPACITY_MULTIPLIER;
+ cxlm->next_volatile_bytes =
+ le64_to_cpu(pi.next_volatile_cap) * CXL_CAPACITY_MULTIPLIER;
+ cxlm->next_persistent_bytes =
+ le64_to_cpu(pi.next_volatile_cap) * CXL_CAPACITY_MULTIPLIER;
+
+ return 0;
+}
+
+/**
+ * cxl_mem_identify() - Send the IDENTIFY command to the device.
+ * @cxlm: The device to identify.
+ *
+ * Return: 0 if identify was executed successfully.
+ *
+ * This will dispatch the identify command to the device and on success populate
+ * structures to be exported to sysfs.
+ */
+int cxl_mem_identify(struct cxl_mem *cxlm)
+{
+ /* See CXL 2.0 Table 175 Identify Memory Device Output Payload */
+ struct cxl_mbox_identify id;
+ int rc;
+
+ rc = cxl_mem_mbox_send_cmd(cxlm, CXL_MBOX_OP_IDENTIFY, NULL, 0, &id,
+ sizeof(id));
+ if (rc < 0)
+ return rc;
+
+ cxlm->total_bytes =
+ le64_to_cpu(id.total_capacity) * CXL_CAPACITY_MULTIPLIER;
+ cxlm->volatile_only_bytes =
+ le64_to_cpu(id.volatile_capacity) * CXL_CAPACITY_MULTIPLIER;
+ cxlm->persistent_only_bytes =
+ le64_to_cpu(id.persistent_capacity) * CXL_CAPACITY_MULTIPLIER;
+ cxlm->partition_align_bytes =
+ le64_to_cpu(id.partition_align) * CXL_CAPACITY_MULTIPLIER;
+
+ dev_dbg(cxlm->dev,
+ "Identify Memory Device\n"
+ " total_bytes = %#llx\n"
+ " volatile_only_bytes = %#llx\n"
+ " persistent_only_bytes = %#llx\n"
+ " partition_align_bytes = %#llx\n",
+ cxlm->total_bytes, cxlm->volatile_only_bytes,
+ cxlm->persistent_only_bytes, cxlm->partition_align_bytes);
+
+ cxlm->lsa_size = le32_to_cpu(id.lsa_size);
+ memcpy(cxlm->firmware_version, id.fw_revision, sizeof(id.fw_revision));
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(cxl_mem_identify);
+
+int cxl_mem_create_range_info(struct cxl_mem *cxlm)
+{
+ int rc;
+
+ if (cxlm->partition_align_bytes == 0) {
+ cxlm->ram_range.start = 0;
+ cxlm->ram_range.end = cxlm->volatile_only_bytes - 1;
+ cxlm->pmem_range.start = cxlm->volatile_only_bytes;
+ cxlm->pmem_range.end = cxlm->volatile_only_bytes +
+ cxlm->persistent_only_bytes - 1;
+ return 0;
+ }
+
+ rc = cxl_mem_get_partition_info(cxlm);
+ if (rc) {
+ dev_err(cxlm->dev, "Failed to query partition information\n");
+ return rc;
+ }
+
+ dev_dbg(cxlm->dev,
+ "Get Partition Info\n"
+ " active_volatile_bytes = %#llx\n"
+ " active_persistent_bytes = %#llx\n"
+ " next_volatile_bytes = %#llx\n"
+ " next_persistent_bytes = %#llx\n",
+ cxlm->active_volatile_bytes, cxlm->active_persistent_bytes,
+ cxlm->next_volatile_bytes, cxlm->next_persistent_bytes);
+
+ cxlm->ram_range.start = 0;
+ cxlm->ram_range.end = cxlm->active_volatile_bytes - 1;
+
+ cxlm->pmem_range.start = cxlm->active_volatile_bytes;
+ cxlm->pmem_range.end =
+ cxlm->active_volatile_bytes + cxlm->active_persistent_bytes - 1;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(cxl_mem_create_range_info);
+
+struct cxl_mem *cxl_mem_create(struct device *dev)
+{
+ struct cxl_mem *cxlm;
+
+ cxlm = devm_kzalloc(dev, sizeof(*cxlm), GFP_KERNEL);
+ if (!cxlm) {
+ dev_err(dev, "No memory available\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ mutex_init(&cxlm->mbox_mutex);
+ cxlm->dev = dev;
+
+ return cxlm;
+}
+EXPORT_SYMBOL_GPL(cxl_mem_create);
+
+static struct dentry *cxl_debugfs;
+
+void __init cxl_mbox_init(void)
+{
+ struct dentry *mbox_debugfs;
+
+ cxl_debugfs = debugfs_create_dir("cxl", NULL);
+ mbox_debugfs = debugfs_create_dir("mbox", cxl_debugfs);
+ debugfs_create_bool("raw_allow_all", 0600, mbox_debugfs,
+ &cxl_raw_allow_all);
+}
+
+void cxl_mbox_exit(void)
+{
+ debugfs_remove_recursive(cxl_debugfs);
+}