[PATCH linux-next v5 03/13] drivers/peci: Add support for PECI bus driver core

From: Jae Hyun Yoo
Date: Fri Jun 01 2018 - 14:21:42 EST


This commit adds driver implementation for PECI bus core into linux
driver framework.

Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@xxxxxxxxxxxxxxx>
Signed-off-by: Fengguang Wu <fengguang.wu@xxxxxxxxx>
Reviewed-by: Haiyue Wang <haiyue.wang@xxxxxxxxxxxxxxx>
Reviewed-by: James Feist <james.feist@xxxxxxxxxxxxxxx>
Reviewed-by: Vernon Mauery <vernon.mauery@xxxxxxxxxxxxxxx>
Cc: Alan Cox <alan@xxxxxxxxxxxxxxx>
Cc: Andrew Lunn <andrew@xxxxxxx>
Cc: Andy Shevchenko <andriy.shevchenko@xxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Fengguang Wu <fengguang.wu@xxxxxxxxx>
Cc: Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Jason M Biils <jason.m.bills@xxxxxxxxxxxxxxx>
Cc: Julia Cartwright <juliac@xxxxxxxxxxxx>
---
drivers/Kconfig | 2 +
drivers/Makefile | 1 +
drivers/peci/Kconfig | 13 +
drivers/peci/Makefile | 6 +
drivers/peci/peci-core.c | 1439 +++++++++++++++++++++++++++++++
include/linux/peci.h | 104 +++
include/uapi/linux/peci-ioctl.h | 265 ++++++
7 files changed, 1830 insertions(+)
create mode 100644 drivers/peci/Kconfig
create mode 100644 drivers/peci/Makefile
create mode 100644 drivers/peci/peci-core.c
create mode 100644 include/linux/peci.h
create mode 100644 include/uapi/linux/peci-ioctl.h

diff --git a/drivers/Kconfig b/drivers/Kconfig
index 95b9ccc08165..8c44d9738377 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -217,4 +217,6 @@ source "drivers/siox/Kconfig"

source "drivers/slimbus/Kconfig"

+source "drivers/peci/Kconfig"
+
endmenu
diff --git a/drivers/Makefile b/drivers/Makefile
index 24cd47014657..250fe3d0fa7e 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -185,3 +185,4 @@ obj-$(CONFIG_TEE) += tee/
obj-$(CONFIG_MULTIPLEXER) += mux/
obj-$(CONFIG_UNISYS_VISORBUS) += visorbus/
obj-$(CONFIG_SIOX) += siox/
+obj-$(CONFIG_PECI) += peci/
diff --git a/drivers/peci/Kconfig b/drivers/peci/Kconfig
new file mode 100644
index 000000000000..c39f7730d081
--- /dev/null
+++ b/drivers/peci/Kconfig
@@ -0,0 +1,13 @@
+#
+# Platform Environment Control Interface (PECI) subsystem configuration
+#
+
+config PECI
+ bool "PECI support"
+ select RT_MUTEXES
+ select CRC8
+ help
+ The Platform Environment Control Interface (PECI) is a one-wire bus
+ interface that provides a communication channel between Intel
+ processors and chipset components to external monitoring or control
+ devices.
diff --git a/drivers/peci/Makefile b/drivers/peci/Makefile
new file mode 100644
index 000000000000..9e8615e0d3ff
--- /dev/null
+++ b/drivers/peci/Makefile
@@ -0,0 +1,6 @@
+#
+# Makefile for the PECI core and bus drivers.
+#
+
+# Core functionality
+obj-$(CONFIG_PECI) += peci-core.o
diff --git a/drivers/peci/peci-core.c b/drivers/peci/peci-core.c
new file mode 100644
index 000000000000..e882a136a540
--- /dev/null
+++ b/drivers/peci/peci-core.c
@@ -0,0 +1,1439 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2018 Intel Corporation
+
+#include <linux/bitfield.h>
+#include <linux/crc8.h>
+#include <linux/delay.h>
+#include <linux/fs.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/peci.h>
+#include <linux/pm_domain.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+
+/* Mask for getting minor revision number from DIB */
+#define MINOR_REV_NUM_MASK GENMASK(11, 8)
+
+/* CRC8 table for Assure Write Frame Check */
+#define PECI_CRC8_POLYNOMIAL 0x07
+DECLARE_CRC8_TABLE(peci_crc8_table);
+
+static struct device_type peci_adapter_type;
+static struct device_type peci_client_type;
+
+/* Max number of peci cdev */
+#define PECI_CDEV_MAX 16
+
+static dev_t peci_devt;
+static bool is_registered;
+
+static DEFINE_MUTEX(core_lock);
+static DEFINE_IDR(peci_adapter_idr);
+
+static struct peci_adapter *peci_get_adapter(int nr)
+{
+ struct peci_adapter *adapter;
+
+ mutex_lock(&core_lock);
+ adapter = idr_find(&peci_adapter_idr, nr);
+ if (!adapter)
+ goto out_unlock;
+
+ if (try_module_get(adapter->owner))
+ get_device(&adapter->dev);
+ else
+ adapter = NULL;
+
+out_unlock:
+ mutex_unlock(&core_lock);
+ return adapter;
+}
+
+static void peci_put_adapter(struct peci_adapter *adapter)
+{
+ if (!adapter)
+ return;
+
+ put_device(&adapter->dev);
+ module_put(adapter->owner);
+}
+
+static ssize_t name_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "%s\n", dev->type == &peci_client_type ?
+ to_peci_client(dev)->name : to_peci_adapter(dev)->name);
+}
+static DEVICE_ATTR_RO(name);
+
+static void peci_client_dev_release(struct device *dev)
+{
+ struct peci_client *client = to_peci_client(dev);
+
+ dev_dbg(dev, "%s: %s\n", __func__, client->name);
+ peci_put_adapter(client->adapter);
+ kfree(client);
+}
+
+static struct attribute *peci_device_attrs[] = {
+ &dev_attr_name.attr,
+ NULL
+};
+ATTRIBUTE_GROUPS(peci_device);
+
+static struct device_type peci_client_type = {
+ .groups = peci_device_groups,
+ .release = peci_client_dev_release,
+};
+
+struct peci_client *peci_verify_client(struct device *dev)
+{
+ return (dev->type == &peci_client_type)
+ ? to_peci_client(dev)
+ : NULL;
+}
+EXPORT_SYMBOL_GPL(peci_verify_client);
+
+static u8 peci_aw_fcs(u8 *data, int len)
+{
+ return crc8(peci_crc8_table, data, (size_t)len, 0);
+}
+
+static int __peci_xfer(struct peci_adapter *adapter, struct peci_xfer_msg *msg,
+ bool do_retry, bool has_aw_fcs)
+{
+ ktime_t start, end;
+ s64 elapsed_ms;
+ int rc = 0;
+
+ /**
+ * For some commands, the PECI originator may need to retry a command if
+ * the processor PECI client responds with a 0x8x completion code. In
+ * each instance, the processor PECI client may have started the
+ * operation but not completed it yet. When the 'retry' bit is set, the
+ * PECI client will ignore a new request if it exactly matches a
+ * previous valid request.
+ */
+
+ if (do_retry)
+ start = ktime_get();
+
+ do {
+ rc = adapter->xfer(adapter, msg);
+
+ if (!do_retry || rc)
+ break;
+
+ if (msg->rx_buf[0] == DEV_PECI_CC_SUCCESS)
+ break;
+
+ /* Retry is needed when completion code is 0x8x */
+ if ((msg->rx_buf[0] & DEV_PECI_CC_RETRY_CHECK_MASK) !=
+ DEV_PECI_CC_NEED_RETRY) {
+ rc = -EIO;
+ break;
+ }
+
+ /* Set the retry bit to indicate a retry attempt */
+ msg->tx_buf[1] |= DEV_PECI_RETRY_BIT;
+
+ /* Recalculate the AW FCS if it has one */
+ if (has_aw_fcs)
+ msg->tx_buf[msg->tx_len - 1] = 0x80 ^
+ peci_aw_fcs((u8 *)msg,
+ 2 + msg->tx_len);
+
+ /**
+ * Retry for at least 250ms before returning an error.
+ * Retry interval guideline:
+ * No minimum < Retry Interval < No maximum
+ * (recommend 10ms)
+ */
+ end = ktime_get();
+ elapsed_ms = ktime_to_ms(ktime_sub(end, start));
+ if (elapsed_ms >= DEV_PECI_RETRY_TIME_MS) {
+ dev_dbg(&adapter->dev, "Timeout retrying xfer!\n");
+ rc = -ETIMEDOUT;
+ break;
+ }
+
+ usleep_range((DEV_PECI_RETRY_INTERVAL_USEC >> 2) + 1,
+ DEV_PECI_RETRY_INTERVAL_USEC);
+ } while (true);
+
+ if (rc)
+ dev_dbg(&adapter->dev, "xfer error, rc: %d\n", rc);
+
+ return rc;
+}
+
+static int peci_xfer(struct peci_adapter *adapter, struct peci_xfer_msg *msg)
+{
+ return __peci_xfer(adapter, msg, false, false);
+}
+
+static int peci_xfer_with_retries(struct peci_adapter *adapter,
+ struct peci_xfer_msg *msg,
+ bool has_aw_fcs)
+{
+ return __peci_xfer(adapter, msg, true, has_aw_fcs);
+}
+
+static int peci_scan_cmd_mask(struct peci_adapter *adapter)
+{
+ struct peci_xfer_msg msg;
+ int rc = 0;
+ u32 dib;
+
+ /* Update command mask just once */
+ if (adapter->cmd_mask & BIT(PECI_CMD_XFER))
+ return 0;
+
+ msg.addr = PECI_BASE_ADDR;
+ msg.tx_len = GET_DIB_WR_LEN;
+ msg.rx_len = GET_DIB_RD_LEN;
+ msg.tx_buf[0] = GET_DIB_PECI_CMD;
+
+ rc = peci_xfer(adapter, &msg);
+ if (rc)
+ return rc;
+
+ dib = le32_to_cpup((__le32 *)msg.rx_buf);
+
+ /* Check special case for Get DIB command */
+ if (dib == 0x00) {
+ dev_dbg(&adapter->dev, "DIB read as 0x00\n");
+ return -EIO;
+ }
+
+ /**
+ * Setting up the supporting commands based on minor revision number.
+ * See PECI Spec Table 3-1.
+ */
+ switch (FIELD_GET(MINOR_REV_NUM_MASK, dib)) {
+ case 6:
+ adapter->cmd_mask |= BIT(PECI_CMD_WR_IA_MSR);
+ /* fallthrough */
+ case 5:
+ adapter->cmd_mask |= BIT(PECI_CMD_WR_PCI_CFG);
+ /* fallthrough */
+ case 4:
+ adapter->cmd_mask |= BIT(PECI_CMD_RD_PCI_CFG);
+ /* fallthrough */
+ case 3:
+ adapter->cmd_mask |= BIT(PECI_CMD_RD_PCI_CFG_LOCAL);
+ adapter->cmd_mask |= BIT(PECI_CMD_WR_PCI_CFG_LOCAL);
+ /* fallthrough */
+ case 2:
+ adapter->cmd_mask |= BIT(PECI_CMD_RD_IA_MSR);
+ /* fallthrough */
+ case 1:
+ adapter->cmd_mask |= BIT(PECI_CMD_RD_PKG_CFG);
+ adapter->cmd_mask |= BIT(PECI_CMD_WR_PKG_CFG);
+ }
+
+ adapter->cmd_mask |= BIT(PECI_CMD_XFER);
+ adapter->cmd_mask |= BIT(PECI_CMD_GET_TEMP);
+ adapter->cmd_mask |= BIT(PECI_CMD_GET_DIB);
+ adapter->cmd_mask |= BIT(PECI_CMD_PING);
+
+ return rc;
+}
+
+static int peci_cmd_support(struct peci_adapter *adapter, enum peci_cmd cmd)
+{
+ if (!(adapter->cmd_mask & BIT(PECI_CMD_PING)) &&
+ peci_scan_cmd_mask(adapter) < 0) {
+ dev_dbg(&adapter->dev, "Failed to scan command mask\n");
+ return -EIO;
+ }
+
+ if (!(adapter->cmd_mask & BIT(cmd))) {
+ dev_dbg(&adapter->dev, "Command %d is not supported\n", cmd);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int peci_ioctl_xfer(struct peci_adapter *adapter, void *vmsg)
+{
+ struct peci_xfer_msg *msg = vmsg;
+
+ return peci_xfer(adapter, msg);
+}
+
+static int peci_ioctl_ping(struct peci_adapter *adapter, void *vmsg)
+{
+ struct peci_ping_msg *umsg = vmsg;
+ struct peci_xfer_msg msg;
+
+ msg.addr = umsg->addr;
+ msg.tx_len = 0;
+ msg.rx_len = 0;
+
+ return peci_xfer(adapter, &msg);
+}
+
+static int peci_ioctl_get_dib(struct peci_adapter *adapter, void *vmsg)
+{
+ struct peci_get_dib_msg *umsg = vmsg;
+ struct peci_xfer_msg msg;
+ int rc;
+
+ msg.addr = umsg->addr;
+ msg.tx_len = GET_DIB_WR_LEN;
+ msg.rx_len = GET_DIB_RD_LEN;
+ msg.tx_buf[0] = GET_DIB_PECI_CMD;
+
+ rc = peci_xfer(adapter, &msg);
+ if (rc)
+ return rc;
+
+ umsg->dib = le32_to_cpup((__le32 *)msg.rx_buf);
+
+ return 0;
+}
+
+static int peci_ioctl_get_temp(struct peci_adapter *adapter, void *vmsg)
+{
+ struct peci_get_temp_msg *umsg = vmsg;
+ struct peci_xfer_msg msg;
+ int rc;
+
+ msg.addr = umsg->addr;
+ msg.tx_len = GET_TEMP_WR_LEN;
+ msg.rx_len = GET_TEMP_RD_LEN;
+ msg.tx_buf[0] = GET_TEMP_PECI_CMD;
+
+ rc = peci_xfer(adapter, &msg);
+ if (rc)
+ return rc;
+
+ umsg->temp_raw = le16_to_cpup((__le16 *)msg.rx_buf);
+
+ return 0;
+}
+
+static int peci_ioctl_rd_pkg_cfg(struct peci_adapter *adapter, void *vmsg)
+{
+ struct peci_rd_pkg_cfg_msg *umsg = vmsg;
+ struct peci_xfer_msg msg;
+ int rc = 0;
+
+ /* Per the PECI spec, the read length must be a byte, word, or dword */
+ if (umsg->rx_len != 1 && umsg->rx_len != 2 && umsg->rx_len != 4) {
+ dev_dbg(&adapter->dev, "Invalid read length, rx_len: %d\n",
+ umsg->rx_len);
+ return -EINVAL;
+ }
+
+ msg.addr = umsg->addr;
+ msg.tx_len = RDPKGCFG_WRITE_LEN;
+ /* read lengths of 1 and 2 result in an error, so only use 4 for now */
+ msg.rx_len = RDPKGCFG_READ_LEN_BASE + umsg->rx_len;
+ msg.tx_buf[0] = RDPKGCFG_PECI_CMD;
+ msg.tx_buf[1] = 0x00; /* request byte for Host ID | Retry bit */
+ /* Host ID is 0 for PECI 3.0 */
+ msg.tx_buf[2] = umsg->index; /* RdPkgConfig index */
+ msg.tx_buf[3] = (u8)umsg->param; /* LSB - Config parameter */
+ msg.tx_buf[4] = (u8)(umsg->param >> 8); /* MSB - Config parameter */
+
+ rc = peci_xfer_with_retries(adapter, &msg, false);
+ if (!rc)
+ memcpy(umsg->pkg_config, &msg.rx_buf[1], umsg->rx_len);
+
+ return rc;
+}
+
+static int peci_ioctl_wr_pkg_cfg(struct peci_adapter *adapter, void *vmsg)
+{
+ struct peci_wr_pkg_cfg_msg *umsg = vmsg;
+ struct peci_xfer_msg msg;
+ int rc = 0, i;
+
+ /* Per the PECI spec, the write length must be a dword */
+ if (umsg->tx_len != 4) {
+ dev_dbg(&adapter->dev, "Invalid write length, tx_len: %d\n",
+ umsg->tx_len);
+ return -EINVAL;
+ }
+
+ msg.addr = umsg->addr;
+ msg.tx_len = WRPKGCFG_WRITE_LEN_BASE + umsg->tx_len;
+ /* read lengths of 1 and 2 result in an error, so only use 4 for now */
+ msg.rx_len = WRPKGCFG_READ_LEN;
+ msg.tx_buf[0] = WRPKGCFG_PECI_CMD;
+ msg.tx_buf[1] = 0x00; /* request byte for Host ID | Retry bit */
+ /* Host ID is 0 for PECI 3.0 */
+ msg.tx_buf[2] = umsg->index; /* RdPkgConfig index */
+ msg.tx_buf[3] = (u8)umsg->param; /* LSB - Config parameter */
+ msg.tx_buf[4] = (u8)(umsg->param >> 8); /* MSB - Config parameter */
+ for (i = 0; i < umsg->tx_len; i++)
+ msg.tx_buf[5 + i] = (u8)(umsg->value >> (i << 3));
+
+ /* Add an Assure Write Frame Check Sequence byte */
+ msg.tx_buf[5 + i] = 0x80 ^
+ peci_aw_fcs((u8 *)&msg, 8 + umsg->tx_len);
+
+ rc = peci_xfer_with_retries(adapter, &msg, true);
+
+ return rc;
+}
+
+static int peci_ioctl_rd_ia_msr(struct peci_adapter *adapter, void *vmsg)
+{
+ struct peci_rd_ia_msr_msg *umsg = vmsg;
+ struct peci_xfer_msg msg;
+ int rc = 0;
+
+ msg.addr = umsg->addr;
+ msg.tx_len = RDIAMSR_WRITE_LEN;
+ msg.rx_len = RDIAMSR_READ_LEN;
+ msg.tx_buf[0] = RDIAMSR_PECI_CMD;
+ msg.tx_buf[1] = 0x00;
+ msg.tx_buf[2] = umsg->thread_id;
+ msg.tx_buf[3] = (u8)umsg->address;
+ msg.tx_buf[4] = (u8)(umsg->address >> 8);
+
+ rc = peci_xfer_with_retries(adapter, &msg, false);
+ if (!rc)
+ memcpy(&umsg->value, &msg.rx_buf[1], sizeof(uint64_t));
+
+ return rc;
+}
+
+static int peci_ioctl_rd_pci_cfg(struct peci_adapter *adapter, void *vmsg)
+{
+ struct peci_rd_pci_cfg_msg *umsg = vmsg;
+ struct peci_xfer_msg msg;
+ u32 address;
+ int rc = 0;
+
+ address = umsg->reg; /* [11:0] - Register */
+ address |= (u32)umsg->function << 12; /* [14:12] - Function */
+ address |= (u32)umsg->device << 15; /* [19:15] - Device */
+ address |= (u32)umsg->bus << 20; /* [27:20] - Bus */
+ /* [31:28] - Reserved */
+ msg.addr = umsg->addr;
+ msg.tx_len = RDPCICFG_WRITE_LEN;
+ msg.rx_len = RDPCICFG_READ_LEN;
+ msg.tx_buf[0] = RDPCICFG_PECI_CMD;
+ msg.tx_buf[1] = 0x00; /* request byte for Host ID | Retry bit */
+ /* Host ID is 0 for PECI 3.0 */
+ msg.tx_buf[2] = (u8)address; /* LSB - PCI Config Address */
+ msg.tx_buf[3] = (u8)(address >> 8); /* PCI Config Address */
+ msg.tx_buf[4] = (u8)(address >> 16); /* PCI Config Address */
+ msg.tx_buf[5] = (u8)(address >> 24); /* MSB - PCI Config Address */
+
+ rc = peci_xfer_with_retries(adapter, &msg, false);
+ if (!rc)
+ memcpy(umsg->pci_config, &msg.rx_buf[1], 4);
+
+ return rc;
+}
+
+static int peci_ioctl_rd_pci_cfg_local(struct peci_adapter *adapter, void *vmsg)
+{
+ struct peci_rd_pci_cfg_local_msg *umsg = vmsg;
+ struct peci_xfer_msg msg;
+ u32 address;
+ int rc = 0;
+
+ /* Per the PECI spec, the read length must be a byte, word, or dword */
+ if (umsg->rx_len != 1 && umsg->rx_len != 2 && umsg->rx_len != 4) {
+ dev_dbg(&adapter->dev, "Invalid read length, rx_len: %d\n",
+ umsg->rx_len);
+ return -EINVAL;
+ }
+
+ address = umsg->reg; /* [11:0] - Register */
+ address |= (u32)umsg->function << 12; /* [14:12] - Function */
+ address |= (u32)umsg->device << 15; /* [19:15] - Device */
+ address |= (u32)umsg->bus << 20; /* [23:20] - Bus */
+
+ msg.addr = umsg->addr;
+ msg.tx_len = RDPCICFGLOCAL_WRITE_LEN;
+ msg.rx_len = RDPCICFGLOCAL_READ_LEN_BASE + umsg->rx_len;
+ msg.tx_buf[0] = RDPCICFGLOCAL_PECI_CMD;
+ msg.tx_buf[1] = 0x00; /* request byte for Host ID | Retry bit */
+ /* Host ID is 0 for PECI 3.0 */
+ msg.tx_buf[2] = (u8)address; /* LSB - PCI Configuration Address */
+ msg.tx_buf[3] = (u8)(address >> 8); /* PCI Configuration Address */
+ msg.tx_buf[4] = (u8)(address >> 16); /* PCI Configuration Address */
+
+ rc = peci_xfer_with_retries(adapter, &msg, false);
+ if (!rc)
+ memcpy(umsg->pci_config, &msg.rx_buf[1], umsg->rx_len);
+
+ return rc;
+}
+
+static int peci_ioctl_wr_pci_cfg_local(struct peci_adapter *adapter, void *vmsg)
+{
+ struct peci_wr_pci_cfg_local_msg *umsg = vmsg;
+ struct peci_xfer_msg msg;
+ int rc = 0, i;
+ u32 address;
+
+ /* Per the PECI spec, the write length must be a byte, word, or dword */
+ if (umsg->tx_len != 1 && umsg->tx_len != 2 && umsg->tx_len != 4) {
+ dev_dbg(&adapter->dev, "Invalid write length, tx_len: %d\n",
+ umsg->tx_len);
+ return -EINVAL;
+ }
+
+ address = umsg->reg; /* [11:0] - Register */
+ address |= (u32)umsg->function << 12; /* [14:12] - Function */
+ address |= (u32)umsg->device << 15; /* [19:15] - Device */
+ address |= (u32)umsg->bus << 20; /* [23:20] - Bus */
+
+ msg.addr = umsg->addr;
+ msg.tx_len = WRPCICFGLOCAL_WRITE_LEN_BASE + umsg->tx_len;
+ msg.rx_len = WRPCICFGLOCAL_READ_LEN;
+ msg.tx_buf[0] = WRPCICFGLOCAL_PECI_CMD;
+ msg.tx_buf[1] = 0x00; /* request byte for Host ID | Retry bit */
+ /* Host ID is 0 for PECI 3.0 */
+ msg.tx_buf[2] = (u8)address; /* LSB - PCI Configuration Address */
+ msg.tx_buf[3] = (u8)(address >> 8); /* PCI Configuration Address */
+ msg.tx_buf[4] = (u8)(address >> 16); /* PCI Configuration Address */
+ for (i = 0; i < umsg->tx_len; i++)
+ msg.tx_buf[5 + i] = (u8)(umsg->value >> (i << 3));
+
+ /* Add an Assure Write Frame Check Sequence byte */
+ msg.tx_buf[5 + i] = 0x80 ^
+ peci_aw_fcs((u8 *)&msg, 8 + umsg->tx_len);
+
+ rc = peci_xfer_with_retries(adapter, &msg, true);
+
+ return rc;
+}
+
+typedef int (*peci_ioctl_fn_type)(struct peci_adapter *, void *);
+
+static const peci_ioctl_fn_type peci_ioctl_fn[PECI_CMD_MAX] = {
+ peci_ioctl_xfer,
+ peci_ioctl_ping,
+ peci_ioctl_get_dib,
+ peci_ioctl_get_temp,
+ peci_ioctl_rd_pkg_cfg,
+ peci_ioctl_wr_pkg_cfg,
+ peci_ioctl_rd_ia_msr,
+ NULL, /* Reserved */
+ peci_ioctl_rd_pci_cfg,
+ NULL, /* Reserved */
+ peci_ioctl_rd_pci_cfg_local,
+ peci_ioctl_wr_pci_cfg_local,
+};
+
+int peci_command(struct peci_adapter *adapter, enum peci_cmd cmd, void *vmsg)
+{
+ int rc = 0;
+
+ if (cmd >= PECI_CMD_MAX || cmd < PECI_CMD_XFER)
+ return -EINVAL;
+
+ dev_dbg(&adapter->dev, "%s, cmd=0x%02x\n", __func__, cmd);
+
+ if (!peci_ioctl_fn[cmd])
+ return -EINVAL;
+
+ rt_mutex_lock(&adapter->bus_lock);
+
+ rc = peci_cmd_support(adapter, cmd);
+ if (!rc)
+ rc = peci_ioctl_fn[cmd](adapter, vmsg);
+
+ rt_mutex_unlock(&adapter->bus_lock);
+
+ return rc;
+}
+EXPORT_SYMBOL_GPL(peci_command);
+
+static long peci_ioctl(struct file *file, unsigned int iocmd, unsigned long arg)
+{
+ struct peci_adapter *adapter = file->private_data;
+ void __user *argp = (void __user *)arg;
+ unsigned int msg_len;
+ enum peci_cmd cmd;
+ int rc = 0;
+ u8 *msg;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ dev_dbg(&adapter->dev, "ioctl, cmd=0x%x, arg=0x%lx\n", iocmd, arg);
+
+ switch (iocmd) {
+ case PECI_IOC_XFER:
+ case PECI_IOC_PING:
+ case PECI_IOC_GET_DIB:
+ case PECI_IOC_GET_TEMP:
+ case PECI_IOC_RD_PKG_CFG:
+ case PECI_IOC_WR_PKG_CFG:
+ case PECI_IOC_RD_IA_MSR:
+ case PECI_IOC_RD_PCI_CFG:
+ case PECI_IOC_RD_PCI_CFG_LOCAL:
+ case PECI_IOC_WR_PCI_CFG_LOCAL:
+ cmd = _IOC_NR(iocmd);
+ msg_len = _IOC_SIZE(iocmd);
+ break;
+
+ default:
+ dev_dbg(&adapter->dev, "Invalid ioctl cmd : 0x%x\n", iocmd);
+ return -ENOTTY;
+ }
+
+ msg = memdup_user(argp, msg_len);
+ if (IS_ERR(msg))
+ return PTR_ERR(msg);
+
+ rc = peci_command(adapter, cmd, msg);
+
+ if (!rc && copy_to_user(argp, msg, msg_len))
+ rc = -EFAULT;
+
+ kfree(msg);
+ return (long)rc;
+}
+
+static int peci_open(struct inode *inode, struct file *file)
+{
+ unsigned int minor = iminor(inode);
+ struct peci_adapter *adapter;
+
+ adapter = peci_get_adapter(minor);
+ if (!adapter)
+ return -ENODEV;
+
+ file->private_data = adapter;
+
+ return 0;
+}
+
+static int peci_release(struct inode *inode, struct file *file)
+{
+ struct peci_adapter *adapter = file->private_data;
+
+ peci_put_adapter(adapter);
+ file->private_data = NULL;
+
+ return 0;
+}
+
+static const struct file_operations peci_fops = {
+ .owner = THIS_MODULE,
+ .unlocked_ioctl = peci_ioctl,
+ .open = peci_open,
+ .release = peci_release,
+};
+
+static int peci_detect(struct peci_adapter *adapter, u8 addr)
+{
+ struct peci_ping_msg msg;
+
+ msg.addr = addr;
+
+ return peci_command(adapter, PECI_CMD_PING, &msg);
+}
+
+static const struct of_device_id *
+peci_of_match_device(const struct of_device_id *matches,
+ struct peci_client *client)
+{
+#if IS_ENABLED(CONFIG_OF)
+ if (!(client && matches))
+ return NULL;
+
+ return of_match_device(matches, &client->dev);
+#else
+ return NULL;
+#endif
+}
+
+static const struct peci_device_id *
+peci_match_id(const struct peci_device_id *id, struct peci_client *client)
+{
+ if (!(id && client))
+ return NULL;
+
+ while (id->name[0]) {
+ if (!strncmp(client->name, id->name, PECI_NAME_SIZE))
+ return id;
+ id++;
+ }
+
+ return NULL;
+}
+
+static int peci_device_match(struct device *dev, struct device_driver *drv)
+{
+ struct peci_client *client = peci_verify_client(dev);
+ struct peci_driver *driver;
+
+ /* Attempt an OF style match */
+ if (peci_of_match_device(drv->of_match_table, client))
+ return 1;
+
+ driver = to_peci_driver(drv);
+
+ /* Finally an ID match */
+ if (peci_match_id(driver->id_table, client))
+ return 1;
+
+ return 0;
+}
+
+static int peci_device_probe(struct device *dev)
+{
+ struct peci_client *client = peci_verify_client(dev);
+ struct peci_driver *driver;
+ int status = -EINVAL;
+
+ if (!client)
+ return 0;
+
+ driver = to_peci_driver(dev->driver);
+
+ if (!driver->id_table &&
+ !peci_of_match_device(dev->driver->of_match_table, client))
+ return -ENODEV;
+
+ dev_dbg(dev, "%s: name:%s\n", __func__, client->name);
+
+ status = dev_pm_domain_attach(&client->dev, true);
+ if (status == -EPROBE_DEFER)
+ return status;
+
+ if (driver->probe)
+ status = driver->probe(client);
+ else
+ status = -EINVAL;
+
+ if (status)
+ goto err_detach_pm_domain;
+
+ return 0;
+
+err_detach_pm_domain:
+ dev_pm_domain_detach(&client->dev, true);
+ return status;
+}
+
+static int peci_device_remove(struct device *dev)
+{
+ struct peci_client *client = peci_verify_client(dev);
+ struct peci_driver *driver;
+ int status = 0;
+
+ if (!client || !dev->driver)
+ return 0;
+
+ driver = to_peci_driver(dev->driver);
+ if (driver->remove) {
+ dev_dbg(dev, "%s: name:%s\n", __func__, client->name);
+ status = driver->remove(client);
+ }
+
+ dev_pm_domain_detach(&client->dev, true);
+
+ return status;
+}
+
+static void peci_device_shutdown(struct device *dev)
+{
+ struct peci_client *client = peci_verify_client(dev);
+ struct peci_driver *driver;
+
+ if (!client || !dev->driver)
+ return;
+
+ dev_dbg(dev, "%s: name:%s\n", __func__, client->name);
+
+ driver = to_peci_driver(dev->driver);
+ if (driver->shutdown)
+ driver->shutdown(client);
+}
+
+static struct bus_type peci_bus_type = {
+ .name = "peci",
+ .match = peci_device_match,
+ .probe = peci_device_probe,
+ .remove = peci_device_remove,
+ .shutdown = peci_device_shutdown,
+};
+
+static int peci_check_addr_validity(u8 addr)
+{
+ if (addr < PECI_BASE_ADDR && addr > PECI_BASE_ADDR + PECI_OFFSET_MAX)
+ return -EINVAL;
+
+ return 0;
+}
+
+static int peci_check_client_busy(struct device *dev, void *client_new_p)
+{
+ struct peci_client *client = peci_verify_client(dev);
+ struct peci_client *client_new = client_new_p;
+
+ if (client && client->addr == client_new->addr)
+ return -EBUSY;
+
+ return 0;
+}
+
+int peci_get_cpu_id(struct peci_adapter *adapter, u8 addr, u32 *cpu_id)
+{
+ struct peci_rd_pkg_cfg_msg msg;
+ int rc;
+
+ msg.addr = addr;
+ msg.index = MBX_INDEX_CPU_ID;
+ msg.param = PKG_ID_CPU_ID;
+ msg.rx_len = 4;
+
+ rc = peci_command(adapter, PECI_CMD_RD_PKG_CFG, &msg);
+ if (!rc)
+ *cpu_id = le32_to_cpup((__le32 *)msg.pkg_config);
+
+ return rc;
+}
+EXPORT_SYMBOL_GPL(peci_get_cpu_id);
+
+static struct peci_client *peci_new_device(struct peci_adapter *adapter,
+ struct peci_board_info const *info)
+{
+ struct peci_client *client;
+ int rc;
+
+ /* Increase reference count for the adapter assigned */
+ if (!peci_get_adapter(adapter->nr))
+ return NULL;
+
+ client = kzalloc(sizeof(*client), GFP_KERNEL);
+ if (!client)
+ goto err_put_adapter;
+
+ client->adapter = adapter;
+ client->addr = info->addr;
+ strlcpy(client->name, info->type, sizeof(client->name));
+
+ rc = peci_check_addr_validity(client->addr);
+ if (rc) {
+ dev_err(&adapter->dev, "Invalid PECI CPU address 0x%02hx\n",
+ client->addr);
+ goto err_free_client_silent;
+ }
+
+ /* Check online status of client */
+ rc = peci_detect(adapter, client->addr);
+ if (rc)
+ goto err_free_client;
+
+ rc = device_for_each_child(&adapter->dev, client,
+ peci_check_client_busy);
+ if (rc)
+ goto err_free_client;
+
+ client->dev.parent = &client->adapter->dev;
+ client->dev.bus = &peci_bus_type;
+ client->dev.type = &peci_client_type;
+ client->dev.of_node = info->of_node;
+ dev_set_name(&client->dev, "%d-%02x", adapter->nr, client->addr);
+
+ rc = device_register(&client->dev);
+ if (rc)
+ goto err_free_client;
+
+ dev_dbg(&adapter->dev, "client [%s] registered with bus id %s\n",
+ client->name, dev_name(&client->dev));
+
+ return client;
+
+err_free_client:
+ dev_err(&adapter->dev,
+ "Failed to register peci client %s at 0x%02x (%d)\n",
+ client->name, client->addr, rc);
+err_free_client_silent:
+ kfree(client);
+err_put_adapter:
+ peci_put_adapter(adapter);
+ return NULL;
+}
+
+static void peci_unregister_device(struct peci_client *client)
+{
+ if (client->dev.of_node)
+ of_node_clear_flag(client->dev.of_node, OF_POPULATED);
+
+ device_unregister(&client->dev);
+}
+
+static int peci_unregister_client(struct device *dev, void *dummy)
+{
+ struct peci_client *client = peci_verify_client(dev);
+
+ if (client)
+ peci_unregister_device(client);
+
+ return 0;
+}
+
+static void peci_adapter_dev_release(struct device *dev)
+{
+ struct peci_adapter *adapter = to_peci_adapter(dev);
+
+ dev_dbg(dev, "%s: %s\n", __func__, adapter->name);
+ mutex_destroy(&adapter->userspace_clients_lock);
+ rt_mutex_destroy(&adapter->bus_lock);
+ kfree(adapter);
+}
+
+static ssize_t peci_sysfs_new_device(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct peci_adapter *adapter = to_peci_adapter(dev);
+ struct peci_board_info info = {};
+ struct peci_client *client;
+ char *blank, end;
+ int rc;
+
+ /* Parse device type */
+ blank = strchr(buf, ' ');
+ if (!blank) {
+ dev_err(dev, "%s: Missing parameters\n", "new_device");
+ return -EINVAL;
+ }
+ if (blank - buf > PECI_NAME_SIZE - 1) {
+ dev_err(dev, "%s: Invalid device type\n", "new_device");
+ return -EINVAL;
+ }
+ memcpy(info.type, buf, blank - buf);
+
+ /* Parse remaining parameters, reject extra parameters */
+ rc = sscanf(++blank, "%hi%c", &info.addr, &end);
+ if (rc < 1) {
+ dev_err(dev, "%s: Can't parse client address\n", "new_device");
+ return -EINVAL;
+ }
+ if (rc > 1 && end != '\n') {
+ dev_err(dev, "%s: Extra parameters\n", "new_device");
+ return -EINVAL;
+ }
+
+ client = peci_new_device(adapter, &info);
+ if (!client)
+ return -EINVAL;
+
+ /* Keep track of the added device */
+ mutex_lock(&adapter->userspace_clients_lock);
+ list_add_tail(&client->detected, &adapter->userspace_clients);
+ mutex_unlock(&adapter->userspace_clients_lock);
+ dev_info(dev, "%s: Instantiated device %s at 0x%02hx\n", "new_device",
+ info.type, info.addr);
+
+ return count;
+}
+static DEVICE_ATTR(new_device, 0200, NULL, peci_sysfs_new_device);
+
+static ssize_t peci_sysfs_delete_device(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct peci_adapter *adapter = to_peci_adapter(dev);
+ struct peci_client *client, *next;
+ struct peci_board_info info = {};
+ struct peci_driver *driver;
+ char *blank, end;
+ int rc;
+
+ /* Parse device type */
+ blank = strchr(buf, ' ');
+ if (!blank) {
+ dev_err(dev, "%s: Missing parameters\n", "delete_device");
+ return -EINVAL;
+ }
+ if (blank - buf > PECI_NAME_SIZE - 1) {
+ dev_err(dev, "%s: Invalid device type\n", "delete_device");
+ return -EINVAL;
+ }
+ memcpy(info.type, buf, blank - buf);
+
+ /* Parse remaining parameters, reject extra parameters */
+ rc = sscanf(++blank, "%hi%c", &info.addr, &end);
+ if (rc < 1) {
+ dev_err(dev, "%s: Can't parse client address\n",
+ "delete_device");
+ return -EINVAL;
+ }
+ if (rc > 1 && end != '\n') {
+ dev_err(dev, "%s: Extra parameters\n", "delete_device");
+ return -EINVAL;
+ }
+
+ /* Make sure the device was added through sysfs */
+ rc = -ENOENT;
+ mutex_lock(&adapter->userspace_clients_lock);
+ list_for_each_entry_safe(client, next, &adapter->userspace_clients,
+ detected) {
+ driver = to_peci_driver(client->dev.driver);
+
+ if (client->addr == info.addr &&
+ !strncmp(client->name, info.type, PECI_NAME_SIZE)) {
+ dev_info(dev, "%s: Deleting device %s at 0x%02hx\n",
+ "delete_device", client->name, client->addr);
+ list_del(&client->detected);
+ peci_unregister_device(client);
+ rc = count;
+ break;
+ }
+ }
+ mutex_unlock(&adapter->userspace_clients_lock);
+
+ if (rc < 0)
+ dev_err(dev, "%s: Can't find device in list\n",
+ "delete_device");
+
+ return rc;
+}
+static DEVICE_ATTR_IGNORE_LOCKDEP(delete_device, 0200, NULL,
+ peci_sysfs_delete_device);
+
+static struct attribute *peci_adapter_attrs[] = {
+ &dev_attr_name.attr,
+ &dev_attr_new_device.attr,
+ &dev_attr_delete_device.attr,
+ NULL
+};
+ATTRIBUTE_GROUPS(peci_adapter);
+
+static struct device_type peci_adapter_type = {
+ .groups = peci_adapter_groups,
+ .release = peci_adapter_dev_release,
+};
+
+struct peci_adapter *peci_verify_adapter(struct device *dev)
+{
+ return (dev->type == &peci_adapter_type)
+ ? to_peci_adapter(dev)
+ : NULL;
+}
+EXPORT_SYMBOL_GPL(peci_verify_adapter);
+
+#if IS_ENABLED(CONFIG_OF)
+static struct peci_client *peci_of_register_device(struct peci_adapter *adapter,
+ struct device_node *node)
+{
+ struct peci_board_info info = {};
+ struct peci_client *result;
+ const __be32 *addr_be;
+ int len;
+
+ dev_dbg(&adapter->dev, "register %s\n", node->full_name);
+
+ if (of_modalias_node(node, info.type, sizeof(info.type)) < 0) {
+ dev_err(&adapter->dev, "modalias failure on %s\n",
+ node->full_name);
+ return ERR_PTR(-EINVAL);
+ }
+
+ addr_be = of_get_property(node, "reg", &len);
+ if (!addr_be || len < sizeof(*addr_be)) {
+ dev_err(&adapter->dev, "invalid reg on %s\n",
+ node->full_name);
+ return ERR_PTR(-EINVAL);
+ }
+
+ info.addr = be32_to_cpup(addr_be);
+ info.of_node = of_node_get(node);
+
+ result = peci_new_device(adapter, &info);
+ if (!result)
+ result = ERR_PTR(-EINVAL);
+
+ of_node_put(node);
+ return result;
+}
+
+static void peci_of_register_devices(struct peci_adapter *adapter)
+{
+ struct device_node *bus, *node;
+ struct peci_client *client;
+
+ /* Only register child devices if the adapter has a node pointer set */
+ if (!adapter->dev.of_node)
+ return;
+
+ bus = of_get_child_by_name(adapter->dev.of_node, "peci-bus");
+ if (!bus)
+ bus = of_node_get(adapter->dev.of_node);
+
+ for_each_available_child_of_node(bus, node) {
+ if (of_node_test_and_set_flag(node, OF_POPULATED))
+ continue;
+
+ client = peci_of_register_device(adapter, node);
+ if (IS_ERR(client)) {
+ dev_warn(&adapter->dev,
+ "Failed to create PECI device for %s\n",
+ node->full_name);
+ of_node_clear_flag(node, OF_POPULATED);
+ }
+ }
+
+ of_node_put(bus);
+}
+#else
+static void peci_of_register_devices(struct peci_adapter *adapter) { }
+#endif /* CONFIG_OF */
+
+#if IS_ENABLED(CONFIG_OF_DYNAMIC)
+static int peci_of_match_node(struct device *dev, void *data)
+{
+ return dev->of_node == data;
+}
+
+/* must call put_device() when done with returned peci_client device */
+static struct peci_client *peci_of_find_device(struct device_node *node)
+{
+ struct peci_client *client;
+ struct device *dev;
+
+ dev = bus_find_device(&peci_bus_type, NULL, node, peci_of_match_node);
+ if (!dev)
+ return NULL;
+
+ client = peci_verify_client(dev);
+ if (!client)
+ put_device(dev);
+
+ return client;
+}
+
+/* must call put_device() when done with returned peci_adapter device */
+static struct peci_adapter *peci_of_find_adapter(struct device_node *node)
+{
+ struct peci_adapter *adapter;
+ struct device *dev;
+
+ dev = bus_find_device(&peci_bus_type, NULL, node, peci_of_match_node);
+ if (!dev)
+ return NULL;
+
+ adapter = peci_verify_adapter(dev);
+ if (!adapter)
+ put_device(dev);
+
+ return adapter;
+}
+
+static int peci_of_notify(struct notifier_block *nb,
+ unsigned long action,
+ void *arg)
+{
+ struct of_reconfig_data *rd = arg;
+ struct peci_adapter *adapter;
+ struct peci_client *client;
+
+ switch (of_reconfig_get_state_change(action, rd)) {
+ case OF_RECONFIG_CHANGE_ADD:
+ adapter = peci_of_find_adapter(rd->dn->parent);
+ if (!adapter)
+ return NOTIFY_OK; /* not for us */
+
+ if (of_node_test_and_set_flag(rd->dn, OF_POPULATED)) {
+ put_device(&adapter->dev);
+ return NOTIFY_OK;
+ }
+
+ client = peci_of_register_device(adapter, rd->dn);
+ put_device(&adapter->dev);
+
+ if (IS_ERR(client)) {
+ dev_err(&adapter->dev,
+ "failed to create client for '%s'\n",
+ rd->dn->full_name);
+ of_node_clear_flag(rd->dn, OF_POPULATED);
+ return notifier_from_errno(PTR_ERR(client));
+ }
+ break;
+ case OF_RECONFIG_CHANGE_REMOVE:
+ /* already depopulated? */
+ if (!of_node_check_flag(rd->dn, OF_POPULATED))
+ return NOTIFY_OK;
+
+ /* find our device by node */
+ client = peci_of_find_device(rd->dn);
+ if (!client)
+ return NOTIFY_OK; /* no? not meant for us */
+
+ /* unregister takes one ref away */
+ peci_unregister_device(client);
+
+ /* and put the reference of the find */
+ put_device(&client->dev);
+ break;
+ }
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block peci_of_notifier = {
+ .notifier_call = peci_of_notify,
+};
+#else
+extern struct notifier_block peci_of_notifier;
+#endif /* CONFIG_OF_DYNAMIC */
+
+struct peci_adapter *peci_alloc_adapter(struct device *dev, unsigned int size)
+{
+ struct peci_adapter *adapter;
+
+ if (!dev)
+ return NULL;
+
+ adapter = kzalloc(size + sizeof(*adapter), GFP_KERNEL);
+ if (!adapter)
+ return NULL;
+
+ device_initialize(&adapter->dev);
+ adapter->dev.parent = dev;
+ adapter->dev.bus = &peci_bus_type;
+ adapter->dev.type = &peci_adapter_type;
+ peci_set_adapdata(adapter, &adapter[1]);
+
+ return adapter;
+}
+EXPORT_SYMBOL_GPL(peci_alloc_adapter);
+
+static int peci_register_adapter(struct peci_adapter *adapter)
+{
+ int rc = -EINVAL;
+
+ /* Can't register until after driver model init */
+ if (WARN_ON(!is_registered))
+ goto err_free_idr;
+
+ if (WARN(!adapter->name[0], "peci adapter has no name"))
+ goto err_free_idr;
+
+ if (WARN(!adapter->xfer, "peci adapter has no xfer function\n"))
+ goto err_free_idr;
+
+ rt_mutex_init(&adapter->bus_lock);
+ mutex_init(&adapter->userspace_clients_lock);
+ INIT_LIST_HEAD(&adapter->userspace_clients);
+
+ dev_set_name(&adapter->dev, "peci%d", adapter->nr);
+
+ /* cdev */
+ cdev_init(&adapter->cdev, &peci_fops);
+ adapter->cdev.owner = THIS_MODULE;
+ adapter->cdev.kobj.parent = &adapter->dev.kobj;
+ adapter->dev.devt = MKDEV(MAJOR(peci_devt), adapter->nr);
+ rc = cdev_add(&adapter->cdev, adapter->dev.devt, 1);
+ if (rc) {
+ pr_err("adapter '%s': can't add cdev (%d)\n",
+ adapter->name, rc);
+ goto err_free_idr;
+ }
+ rc = device_add(&adapter->dev);
+ if (rc) {
+ pr_err("adapter '%s': can't add device (%d)\n",
+ adapter->name, rc);
+ goto err_del_cdev;
+ }
+
+ dev_dbg(&adapter->dev, "adapter [%s] registered\n", adapter->name);
+
+ pm_runtime_no_callbacks(&adapter->dev);
+ pm_suspend_ignore_children(&adapter->dev, true);
+ pm_runtime_enable(&adapter->dev);
+
+ /* create pre-declared device nodes */
+ peci_of_register_devices(adapter);
+
+ return 0;
+
+err_del_cdev:
+ cdev_del(&adapter->cdev);
+err_free_idr:
+ mutex_lock(&core_lock);
+ idr_remove(&peci_adapter_idr, adapter->nr);
+ mutex_unlock(&core_lock);
+ return rc;
+}
+
+static int peci_add_numbered_adapter(struct peci_adapter *adapter)
+{
+ int id;
+
+ mutex_lock(&core_lock);
+ id = idr_alloc(&peci_adapter_idr, adapter,
+ adapter->nr, adapter->nr + 1, GFP_KERNEL);
+ mutex_unlock(&core_lock);
+ if (WARN(id < 0, "couldn't get idr"))
+ return id == -ENOSPC ? -EBUSY : id;
+
+ return peci_register_adapter(adapter);
+}
+
+int peci_add_adapter(struct peci_adapter *adapter)
+{
+ struct device *dev = &adapter->dev;
+ int id;
+
+ if (dev->of_node) {
+ id = of_alias_get_id(dev->of_node, "peci");
+ if (id >= 0) {
+ adapter->nr = id;
+ return peci_add_numbered_adapter(adapter);
+ }
+ }
+
+ mutex_lock(&core_lock);
+ id = idr_alloc(&peci_adapter_idr, adapter, 0, 0, GFP_KERNEL);
+ mutex_unlock(&core_lock);
+ if (WARN(id < 0, "couldn't get idr"))
+ return id;
+
+ adapter->nr = id;
+
+ return peci_register_adapter(adapter);
+}
+EXPORT_SYMBOL_GPL(peci_add_adapter);
+
+void peci_del_adapter(struct peci_adapter *adapter)
+{
+ struct peci_client *client, *next;
+ struct peci_adapter *found;
+ int nr;
+
+ /* First make sure that this adapter was ever added */
+ mutex_lock(&core_lock);
+ found = idr_find(&peci_adapter_idr, adapter->nr);
+ mutex_unlock(&core_lock);
+
+ if (found != adapter)
+ return;
+
+ /* Remove devices instantiated from sysfs */
+ mutex_lock(&adapter->userspace_clients_lock);
+ list_for_each_entry_safe(client, next, &adapter->userspace_clients,
+ detected) {
+ dev_dbg(&adapter->dev, "Removing %s at 0x%x\n", client->name,
+ client->addr);
+ list_del(&client->detected);
+ peci_unregister_device(client);
+ }
+ mutex_unlock(&adapter->userspace_clients_lock);
+
+ /**
+ * Detach any active clients. This can't fail, thus we do not
+ * check the returned value.
+ */
+ device_for_each_child(&adapter->dev, NULL, peci_unregister_client);
+
+ /* device name is gone after device_unregister */
+ dev_dbg(&adapter->dev, "adapter [%s] unregistered\n", adapter->name);
+
+ /* free cdev */
+ cdev_del(&adapter->cdev);
+
+ pm_runtime_disable(&adapter->dev);
+
+ nr = adapter->nr;
+
+ device_unregister(&adapter->dev);
+
+ /* free bus id */
+ mutex_lock(&core_lock);
+ idr_remove(&peci_adapter_idr, nr);
+ mutex_unlock(&core_lock);
+}
+EXPORT_SYMBOL_GPL(peci_del_adapter);
+
+/**
+ * A peci_driver is used with one or more peci_client (device) nodes to access
+ * peci clients, on a bus instance associated with some peci_adapter.
+ */
+int peci_register_driver(struct module *owner, struct peci_driver *driver)
+{
+ int rc;
+
+ /* Can't register until after driver model init */
+ if (WARN_ON(!is_registered))
+ return -EAGAIN;
+
+ /* add the driver to the list of peci drivers in the driver core */
+ driver->driver.owner = owner;
+ driver->driver.bus = &peci_bus_type;
+
+ /**
+ * When registration returns, the driver core
+ * will have called probe() for all matching-but-unbound devices.
+ */
+ rc = driver_register(&driver->driver);
+ if (rc)
+ return rc;
+
+ pr_debug("driver [%s] registered\n", driver->driver.name);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(peci_register_driver);
+
+void peci_del_driver(struct peci_driver *driver)
+{
+ driver_unregister(&driver->driver);
+ pr_debug("driver [%s] unregistered\n", driver->driver.name);
+}
+EXPORT_SYMBOL_GPL(peci_del_driver);
+
+static int __init peci_init(void)
+{
+ int ret;
+
+ ret = bus_register(&peci_bus_type);
+ if (ret < 0) {
+ pr_err("peci: Failed to register PECI bus type!\n");
+ return ret;
+ }
+
+ ret = alloc_chrdev_region(&peci_devt, 0, PECI_CDEV_MAX, "peci");
+ if (ret < 0) {
+ pr_err("peci: Failed to allocate chr dev region!\n");
+ bus_unregister(&peci_bus_type);
+ return ret;
+ }
+
+ crc8_populate_msb(peci_crc8_table, PECI_CRC8_POLYNOMIAL);
+
+ if (IS_ENABLED(CONFIG_OF_DYNAMIC))
+ WARN_ON(of_reconfig_notifier_register(&peci_of_notifier));
+
+ is_registered = true;
+
+ return 0;
+}
+
+static void __exit peci_exit(void)
+{
+ if (IS_ENABLED(CONFIG_OF_DYNAMIC))
+ WARN_ON(of_reconfig_notifier_unregister(&peci_of_notifier));
+
+ unregister_chrdev_region(peci_devt, PECI_CDEV_MAX);
+ bus_unregister(&peci_bus_type);
+}
+
+postcore_initcall(peci_init);
+module_exit(peci_exit);
+
+MODULE_AUTHOR("Jason M Biils <jason.m.bills@xxxxxxxxxxxxxxx>");
+MODULE_AUTHOR("Jae Hyun Yoo <jae.hyun.yoo@xxxxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("PECI bus core module");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/peci.h b/include/linux/peci.h
new file mode 100644
index 000000000000..425c9cdab6dc
--- /dev/null
+++ b/include/linux/peci.h
@@ -0,0 +1,104 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (c) 2018 Intel Corporation */
+
+#ifndef __LINUX_PECI_H
+#define __LINUX_PECI_H
+
+#include <linux/cdev.h>
+#include <linux/device.h>
+#include <linux/peci-ioctl.h>
+#include <linux/rtmutex.h>
+
+#define PECI_NAME_SIZE 32
+
+struct peci_board_info {
+ char type[PECI_NAME_SIZE];
+ unsigned short addr; /* CPU client address */
+ struct device_node *of_node;
+};
+
+struct peci_adapter {
+ struct module *owner;
+ struct rt_mutex bus_lock;
+ struct device dev;
+ struct cdev cdev;
+ int nr;
+ char name[PECI_NAME_SIZE];
+ struct mutex userspace_clients_lock; /* clients list mutex */
+ struct list_head userspace_clients;
+ int (*xfer)(struct peci_adapter *adapter,
+ struct peci_xfer_msg *msg);
+ uint cmd_mask;
+};
+
+static inline struct peci_adapter *to_peci_adapter(void *d)
+{
+ return container_of(d, struct peci_adapter, dev);
+}
+
+static inline void *peci_get_adapdata(const struct peci_adapter *adapter)
+{
+ return dev_get_drvdata(&adapter->dev);
+}
+
+static inline void peci_set_adapdata(struct peci_adapter *adapter, void *data)
+{
+ dev_set_drvdata(&adapter->dev, data);
+}
+
+struct peci_client {
+ struct device dev; /* the device structure */
+ struct peci_adapter *adapter; /* the adapter we sit on */
+ u8 addr; /* CPU client address */
+ char name[PECI_NAME_SIZE];
+ struct list_head detected;
+};
+
+static inline struct peci_client *to_peci_client(void *d)
+{
+ return container_of(d, struct peci_client, dev);
+}
+
+struct peci_device_id {
+ char name[PECI_NAME_SIZE];
+ unsigned long driver_data; /* Data private to the driver */
+};
+
+struct peci_driver {
+ int (*probe)(struct peci_client *client);
+ int (*remove)(struct peci_client *client);
+ void (*shutdown)(struct peci_client *client);
+ struct device_driver driver;
+ const struct peci_device_id *id_table;
+};
+
+static inline struct peci_driver *to_peci_driver(void *d)
+{
+ return container_of(d, struct peci_driver, driver);
+}
+
+/**
+ * module_peci_driver() - Helper macro for registering a modular PECI driver
+ * @__peci_driver: peci_driver struct
+ *
+ * Helper macro for PECI drivers which do not do anything special in module
+ * init/exit. This eliminates a lot of boilerplate. Each module may only
+ * use this macro once, and calling it replaces module_init() and module_exit()
+ */
+#define module_peci_driver(__peci_driver) \
+ module_driver(__peci_driver, peci_add_driver, peci_del_driver)
+
+/* use a define to avoid include chaining to get THIS_MODULE */
+#define peci_add_driver(driver) peci_register_driver(THIS_MODULE, driver)
+
+int peci_register_driver(struct module *owner, struct peci_driver *drv);
+void peci_del_driver(struct peci_driver *driver);
+struct peci_client *peci_verify_client(struct device *dev);
+struct peci_adapter *peci_alloc_adapter(struct device *dev, unsigned int size);
+int peci_add_adapter(struct peci_adapter *adapter);
+void peci_del_adapter(struct peci_adapter *adapter);
+struct peci_adapter *peci_verify_adapter(struct device *dev);
+int peci_command(struct peci_adapter *adpater, enum peci_cmd cmd, void *vmsg);
+int peci_get_cpu_id(struct peci_adapter *adapter, u8 addr, u32 *cpu_id);
+
+#endif /* __LINUX_PECI_H */
diff --git a/include/uapi/linux/peci-ioctl.h b/include/uapi/linux/peci-ioctl.h
new file mode 100644
index 000000000000..2438f2b586fd
--- /dev/null
+++ b/include/uapi/linux/peci-ioctl.h
@@ -0,0 +1,265 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (c) 2018 Intel Corporation */
+
+#ifndef __PECI_IOCTL_H
+#define __PECI_IOCTL_H
+
+#include <linux/ioctl.h>
+#include <linux/types.h>
+
+/* Base Address of 48d */
+#define PECI_BASE_ADDR 0x30 /* The PECI client's default address of 0x30 */
+#define PECI_OFFSET_MAX 8 /* Max numver of CPU clients */
+
+/* PCI Access */
+#define MAX_PCI_READ_LEN 24 /* Number of bytes of the PCI Space read */
+
+#define PCI_BUS0_CPU0 0x00
+#define PCI_BUS0_CPU1 0x80
+#define PCI_CPUBUSNO_BUS 0x00
+#define PCI_CPUBUSNO_DEV 0x08
+#define PCI_CPUBUSNO_FUNC 0x02
+#define PCI_CPUBUSNO 0xcc
+#define PCI_CPUBUSNO_1 0xd0
+#define PCI_CPUBUSNO_VALID 0xd4
+
+/* Package Identifier Read Parameter Value */
+#define PKG_ID_CPU_ID 0x0000 /* CPUID Info */
+#define PKG_ID_PLATFORM_ID 0x0001 /* Platform ID */
+#define PKG_ID_UNCORE_ID 0x0002 /* Uncore Device ID */
+#define PKG_ID_MAX_THREAD_ID 0x0003 /* Max Thread ID */
+#define PKG_ID_MICROCODE_REV 0x0004 /* CPU Microcode Update Revision */
+#define PKG_ID_MACHINE_CHECK_STATUS 0x0005 /* Machine Check Status */
+
+/* RdPkgConfig Index */
+#define MBX_INDEX_CPU_ID 0 /* Package Identifier Read */
+#define MBX_INDEX_VR_DEBUG 1 /* VR Debug */
+#define MBX_INDEX_PKG_TEMP_READ 2 /* Package Temperature Read */
+#define MBX_INDEX_ENERGY_COUNTER 3 /* Energy counter */
+#define MBX_INDEX_ENERGY_STATUS 4 /* DDR Energy Status */
+#define MBX_INDEX_WAKE_MODE_BIT 5 /* "Wake on PECI" Mode bit */
+#define MBX_INDEX_EPI 6 /* Efficient Performance Indication */
+#define MBX_INDEX_PKG_RAPL_PERF 8 /* Pkg RAPL Performance Status Read */
+#define MBX_INDEX_PER_CORE_DTS_TEMP 9 /* Per Core DTS Temperature Read */
+#define MBX_INDEX_DTS_MARGIN 10 /* DTS thermal margin */
+#define MBX_INDEX_SKT_PWR_THRTL_DUR 11 /* Socket Power Throttled Duration */
+#define MBX_INDEX_CFG_TDP_CONTROL 12 /* TDP Config Control */
+#define MBX_INDEX_CFG_TDP_LEVELS 13 /* TDP Config Levels */
+#define MBX_INDEX_DDR_DIMM_TEMP 14 /* DDR DIMM Temperature */
+#define MBX_INDEX_CFG_ICCMAX 15 /* Configurable ICCMAX */
+#define MBX_INDEX_TEMP_TARGET 16 /* Temperature Target Read */
+#define MBX_INDEX_CURR_CFG_LIMIT 17 /* Current Config Limit */
+#define MBX_INDEX_DIMM_TEMP_READ 20 /* Package Thermal Status Read */
+#define MBX_INDEX_DRAM_IMC_TMP_READ 22 /* DRAM IMC Temperature Read */
+#define MBX_INDEX_DDR_CH_THERM_STAT 23 /* DDR Channel Thermal Status */
+#define MBX_INDEX_PKG_POWER_LIMIT1 26 /* Package Power Limit1 */
+#define MBX_INDEX_PKG_POWER_LIMIT2 27 /* Package Power Limit2 */
+#define MBX_INDEX_TDP 28 /* Thermal design power minimum */
+#define MBX_INDEX_TDP_HIGH 29 /* Thermal design power maximum */
+#define MBX_INDEX_TDP_UNITS 30 /* Units for power/energy registers */
+#define MBX_INDEX_RUN_TIME 31 /* Accumulated Run Time */
+#define MBX_INDEX_CONSTRAINED_TIME 32 /* Thermally Constrained Time Read */
+#define MBX_INDEX_TURBO_RATIO 33 /* Turbo Activation Ratio */
+#define MBX_INDEX_DDR_RAPL_PL1 34 /* DDR RAPL PL1 */
+#define MBX_INDEX_DDR_PWR_INFO_HIGH 35 /* DRAM Power Info Read (high) */
+#define MBX_INDEX_DDR_PWR_INFO_LOW 36 /* DRAM Power Info Read (low) */
+#define MBX_INDEX_DDR_RAPL_PL2 37 /* DDR RAPL PL2 */
+#define MBX_INDEX_DDR_RAPL_STATUS 38 /* DDR RAPL Performance Status */
+#define MBX_INDEX_DDR_HOT_ABSOLUTE 43 /* DDR Hottest Dimm Absolute Temp */
+#define MBX_INDEX_DDR_HOT_RELATIVE 44 /* DDR Hottest Dimm Relative Temp */
+#define MBX_INDEX_DDR_THROTTLE_TIME 45 /* DDR Throttle Time */
+#define MBX_INDEX_DDR_THERM_STATUS 46 /* DDR Thermal Status */
+#define MBX_INDEX_TIME_AVG_TEMP 47 /* Package time-averaged temperature */
+#define MBX_INDEX_TURBO_RATIO_LIMIT 49 /* Turbo Ratio Limit Read */
+#define MBX_INDEX_HWP_AUTO_OOB 53 /* HWP Autonomous Out-of-band */
+#define MBX_INDEX_DDR_WARM_BUDGET 55 /* DDR Warm Power Budget */
+#define MBX_INDEX_DDR_HOT_BUDGET 56 /* DDR Hot Power Budget */
+#define MBX_INDEX_PKG_PSYS_PWR_LIM3 57 /* Package/Psys Power Limit3 */
+#define MBX_INDEX_PKG_PSYS_PWR_LIM1 58 /* Package/Psys Power Limit1 */
+#define MBX_INDEX_PKG_PSYS_PWR_LIM2 59 /* Package/Psys Power Limit2 */
+#define MBX_INDEX_PKG_PSYS_PWR_LIM4 60 /* Package/Psys Power Limit4 */
+#define MBX_INDEX_PERF_LIMIT_REASON 65 /* Performance Limit Reasons */
+
+/* WrPkgConfig Index */
+#define MBX_INDEX_DIMM_AMBIENT 19
+#define MBX_INDEX_DIMM_TEMP 24
+
+/* Device Specific Completion Code (CC) Definition */
+#define DEV_PECI_CC_SUCCESS 0x40
+#define DEV_PECI_CC_TIMEOUT 0x80
+#define DEV_PECI_CC_OUT_OF_RESOURCE 0x81
+#define DEV_PECI_CC_UNAVAIL_RESOURCE 0x82
+#define DEV_PECI_CC_INVALID_REQ 0x90
+
+/* Completion Code mask to check retry needs */
+#define DEV_PECI_CC_RETRY_CHECK_MASK 0xf0
+#define DEV_PECI_CC_NEED_RETRY 0x80
+
+/* Skylake EDS says to retry for 250ms */
+#define DEV_PECI_RETRY_TIME_MS 250
+#define DEV_PECI_RETRY_INTERVAL_USEC 10000
+#define DEV_PECI_RETRY_BIT 0x01
+
+#define GET_TEMP_WR_LEN 1
+#define GET_TEMP_RD_LEN 2
+#define GET_TEMP_PECI_CMD 0x01
+
+#define GET_DIB_WR_LEN 1
+#define GET_DIB_RD_LEN 8
+#define GET_DIB_PECI_CMD 0xf7
+
+#define RDPKGCFG_WRITE_LEN 5
+#define RDPKGCFG_READ_LEN_BASE 1
+#define RDPKGCFG_PECI_CMD 0xa1
+
+#define WRPKGCFG_WRITE_LEN_BASE 6
+#define WRPKGCFG_READ_LEN 1
+#define WRPKGCFG_PECI_CMD 0xa5
+
+#define RDIAMSR_WRITE_LEN 5
+#define RDIAMSR_READ_LEN 9
+#define RDIAMSR_PECI_CMD 0xb1
+
+#define WRIAMSR_PECI_CMD 0xb5
+
+#define RDPCICFG_WRITE_LEN 6
+#define RDPCICFG_READ_LEN 5
+#define RDPCICFG_PECI_CMD 0x61
+
+#define WRPCICFG_PECI_CMD 0x65
+
+#define RDPCICFGLOCAL_WRITE_LEN 5
+#define RDPCICFGLOCAL_READ_LEN_BASE 1
+#define RDPCICFGLOCAL_PECI_CMD 0xe1
+
+#define WRPCICFGLOCAL_WRITE_LEN_BASE 6
+#define WRPCICFGLOCAL_READ_LEN 1
+#define WRPCICFGLOCAL_PECI_CMD 0xe5
+
+#define PECI_BUFFER_SIZE 32
+
+enum peci_cmd {
+ PECI_CMD_XFER = 0,
+ PECI_CMD_PING,
+ PECI_CMD_GET_DIB,
+ PECI_CMD_GET_TEMP,
+ PECI_CMD_RD_PKG_CFG,
+ PECI_CMD_WR_PKG_CFG,
+ PECI_CMD_RD_IA_MSR,
+ PECI_CMD_WR_IA_MSR,
+ PECI_CMD_RD_PCI_CFG,
+ PECI_CMD_WR_PCI_CFG,
+ PECI_CMD_RD_PCI_CFG_LOCAL,
+ PECI_CMD_WR_PCI_CFG_LOCAL,
+ PECI_CMD_MAX
+};
+
+struct peci_xfer_msg {
+ __u8 addr;
+ __u8 tx_len;
+ __u8 rx_len;
+ __u8 tx_buf[PECI_BUFFER_SIZE];
+ __u8 rx_buf[PECI_BUFFER_SIZE];
+} __attribute__((__packed__));
+
+struct peci_ping_msg {
+ __u8 addr;
+} __attribute__((__packed__));
+
+struct peci_get_dib_msg {
+ __u8 addr;
+ __u32 dib;
+} __attribute__((__packed__));
+
+struct peci_get_temp_msg {
+ __u8 addr;
+ __s16 temp_raw;
+} __attribute__((__packed__));
+
+struct peci_rd_pkg_cfg_msg {
+ __u8 addr;
+ __u8 index;
+ __u16 param;
+ __u8 rx_len;
+ __u8 pkg_config[4];
+} __attribute__((__packed__));
+
+struct peci_wr_pkg_cfg_msg {
+ __u8 addr;
+ __u8 index;
+ __u16 param;
+ __u8 tx_len;
+ __u32 value;
+} __attribute__((__packed__));
+
+struct peci_rd_ia_msr_msg {
+ __u8 addr;
+ __u8 thread_id;
+ __u16 address;
+ __u64 value;
+} __attribute__((__packed__));
+
+struct peci_rd_pci_cfg_msg {
+ __u8 addr;
+ __u8 bus;
+ __u8 device;
+ __u8 function;
+ __u16 reg;
+ __u8 pci_config[4];
+} __attribute__((__packed__));
+
+struct peci_rd_pci_cfg_local_msg {
+ __u8 addr;
+ __u8 bus;
+ __u8 device;
+ __u8 function;
+ __u16 reg;
+ __u8 rx_len;
+ __u8 pci_config[4];
+} __attribute__((__packed__));
+
+struct peci_wr_pci_cfg_local_msg {
+ __u8 addr;
+ __u8 bus;
+ __u8 device;
+ __u8 function;
+ __u16 reg;
+ __u8 tx_len;
+ __u32 value;
+} __attribute__((__packed__));
+
+#define PECI_IOC_BASE 0xb6
+
+#define PECI_IOC_XFER \
+ _IOWR(PECI_IOC_BASE, PECI_CMD_XFER, struct peci_xfer_msg)
+
+#define PECI_IOC_PING \
+ _IOWR(PECI_IOC_BASE, PECI_CMD_PING, struct peci_ping_msg)
+
+#define PECI_IOC_GET_DIB \
+ _IOWR(PECI_IOC_BASE, PECI_CMD_GET_DIB, struct peci_get_dib_msg)
+
+#define PECI_IOC_GET_TEMP \
+ _IOWR(PECI_IOC_BASE, PECI_CMD_GET_TEMP, struct peci_get_temp_msg)
+
+#define PECI_IOC_RD_PKG_CFG \
+ _IOWR(PECI_IOC_BASE, PECI_CMD_RD_PKG_CFG, struct peci_rd_pkg_cfg_msg)
+
+#define PECI_IOC_WR_PKG_CFG \
+ _IOWR(PECI_IOC_BASE, PECI_CMD_WR_PKG_CFG, struct peci_wr_pkg_cfg_msg)
+
+#define PECI_IOC_RD_IA_MSR \
+ _IOWR(PECI_IOC_BASE, PECI_CMD_RD_IA_MSR, struct peci_rd_ia_msr_msg)
+
+#define PECI_IOC_RD_PCI_CFG \
+ _IOWR(PECI_IOC_BASE, PECI_CMD_RD_PCI_CFG, struct peci_rd_pci_cfg_msg)
+
+#define PECI_IOC_RD_PCI_CFG_LOCAL \
+ _IOWR(PECI_IOC_BASE, PECI_CMD_RD_PCI_CFG_LOCAL, \
+ struct peci_rd_pci_cfg_local_msg)
+
+#define PECI_IOC_WR_PCI_CFG_LOCAL \
+ _IOWR(PECI_IOC_BASE, PECI_CMD_WR_PCI_CFG_LOCAL, \
+ struct peci_wr_pci_cfg_local_msg)
+
+#endif /* __PECI_IOCTL_H */
--
2.17.0