[PATCH] hwmon: Remove xgene driver

From: D Scott Phillips
Date: Fri Jun 03 2022 - 12:54:04 EST


Similar to the situation in commit 9049572fb145 ("hwmon: Remove amd_energy
driver"), access to power information can be used as the basis for a side-
channel attack. Removing unprivileged access to monitoring information
would effectively make the driver useless, so simply remove the driver.

Fixes: ed42cfa881e1 ("hwmon: Add xgene hwmon driver")
Signed-off-by: D Scott Phillips <scott@xxxxxxxxxxxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
---

I've put a cc: stable here, though I see that wasn't done for the removal
of the amd_energy driver. I'm assuming that removing a driver wouldn't
normally be sent to stable, but should it be if it's being removed for a
security issue?

drivers/hwmon/Kconfig | 7 -
drivers/hwmon/Makefile | 1 -
drivers/hwmon/xgene-hwmon.c | 792 ------------------------------------
3 files changed, 800 deletions(-)
delete mode 100644 drivers/hwmon/xgene-hwmon.c

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 590d3d550acb..382157c7f681 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -2280,13 +2280,6 @@ config SENSORS_ULTRA45
This driver provides support for the Ultra45 workstation environmental
sensors.

-config SENSORS_XGENE
- tristate "APM X-Gene SoC hardware monitoring driver"
- depends on XGENE_SLIMPRO_MBOX || PCC
- help
- If you say yes here you get support for the temperature
- and power sensors for APM X-Gene SoC.
-
config SENSORS_INTEL_M10_BMC_HWMON
tristate "Intel MAX10 BMC Hardware Monitoring"
depends on MFD_INTEL_M10_BMC
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 007e829d1d0d..fe8fa99f3960 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -212,7 +212,6 @@ obj-$(CONFIG_SENSORS_W83L785TS) += w83l785ts.o
obj-$(CONFIG_SENSORS_W83L786NG) += w83l786ng.o
obj-$(CONFIG_SENSORS_WM831X) += wm831x-hwmon.o
obj-$(CONFIG_SENSORS_WM8350) += wm8350-hwmon.o
-obj-$(CONFIG_SENSORS_XGENE) += xgene-hwmon.o

obj-$(CONFIG_SENSORS_OCC) += occ/
obj-$(CONFIG_SENSORS_PECI) += peci/
diff --git a/drivers/hwmon/xgene-hwmon.c b/drivers/hwmon/xgene-hwmon.c
deleted file mode 100644
index 5cde837bfd09..000000000000
--- a/drivers/hwmon/xgene-hwmon.c
+++ /dev/null
@@ -1,792 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * APM X-Gene SoC Hardware Monitoring Driver
- *
- * Copyright (c) 2016, Applied Micro Circuits Corporation
- * Author: Loc Ho <lho@xxxxxxx>
- * Hoan Tran <hotran@xxxxxxx>
- *
- * This driver provides the following features:
- * - Retrieve CPU total power (uW)
- * - Retrieve IO total power (uW)
- * - Retrieve SoC temperature (milli-degree C) and alarm
- */
-#include <linux/acpi.h>
-#include <linux/dma-mapping.h>
-#include <linux/hwmon.h>
-#include <linux/hwmon-sysfs.h>
-#include <linux/io.h>
-#include <linux/interrupt.h>
-#include <linux/kfifo.h>
-#include <linux/mailbox_controller.h>
-#include <linux/mailbox_client.h>
-#include <linux/module.h>
-#include <linux/of.h>
-#include <linux/platform_device.h>
-
-#include <acpi/pcc.h>
-
-/* SLIMpro message defines */
-#define MSG_TYPE_DBG 0
-#define MSG_TYPE_ERR 7
-#define MSG_TYPE_PWRMGMT 9
-
-#define MSG_TYPE(v) (((v) & 0xF0000000) >> 28)
-#define MSG_TYPE_SET(v) (((v) << 28) & 0xF0000000)
-#define MSG_SUBTYPE(v) (((v) & 0x0F000000) >> 24)
-#define MSG_SUBTYPE_SET(v) (((v) << 24) & 0x0F000000)
-
-#define DBG_SUBTYPE_SENSOR_READ 4
-#define SENSOR_RD_MSG 0x04FFE902
-#define SENSOR_RD_EN_ADDR(a) ((a) & 0x000FFFFF)
-#define PMD_PWR_REG 0x20
-#define PMD_PWR_MW_REG 0x26
-#define SOC_PWR_REG 0x21
-#define SOC_PWR_MW_REG 0x27
-#define SOC_TEMP_REG 0x10
-
-#define TEMP_NEGATIVE_BIT 8
-#define SENSOR_INVALID_DATA BIT(15)
-
-#define PWRMGMT_SUBTYPE_TPC 1
-#define TPC_ALARM 2
-#define TPC_GET_ALARM 3
-#define TPC_CMD(v) (((v) & 0x00FF0000) >> 16)
-#define TPC_CMD_SET(v) (((v) << 16) & 0x00FF0000)
-#define TPC_EN_MSG(hndl, cmd, type) \
- (MSG_TYPE_SET(MSG_TYPE_PWRMGMT) | \
- MSG_SUBTYPE_SET(hndl) | TPC_CMD_SET(cmd) | type)
-
-/* PCC defines */
-#define PCC_SIGNATURE_MASK 0x50424300
-#define PCCC_GENERATE_DB_INT BIT(15)
-#define PCCS_CMD_COMPLETE BIT(0)
-#define PCCS_SCI_DOORBEL BIT(1)
-#define PCCS_PLATFORM_NOTIFICATION BIT(3)
-/*
- * Arbitrary retries in case the remote processor is slow to respond
- * to PCC commands
- */
-#define PCC_NUM_RETRIES 500
-
-#define ASYNC_MSG_FIFO_SIZE 16
-#define MBOX_OP_TIMEOUTMS 1000
-
-#define WATT_TO_mWATT(x) ((x) * 1000)
-#define mWATT_TO_uWATT(x) ((x) * 1000)
-#define CELSIUS_TO_mCELSIUS(x) ((x) * 1000)
-
-#define to_xgene_hwmon_dev(cl) \
- container_of(cl, struct xgene_hwmon_dev, mbox_client)
-
-enum xgene_hwmon_version {
- XGENE_HWMON_V1 = 0,
- XGENE_HWMON_V2 = 1,
-};
-
-struct slimpro_resp_msg {
- u32 msg;
- u32 param1;
- u32 param2;
-} __packed;
-
-struct xgene_hwmon_dev {
- struct device *dev;
- struct mbox_chan *mbox_chan;
- struct pcc_mbox_chan *pcc_chan;
- struct mbox_client mbox_client;
- int mbox_idx;
-
- spinlock_t kfifo_lock;
- struct mutex rd_mutex;
- struct completion rd_complete;
- int resp_pending;
- struct slimpro_resp_msg sync_msg;
-
- struct work_struct workq;
- struct kfifo_rec_ptr_1 async_msg_fifo;
-
- struct device *hwmon_dev;
- bool temp_critical_alarm;
-
- phys_addr_t comm_base_addr;
- void *pcc_comm_addr;
- u64 usecs_lat;
-};
-
-/*
- * This function tests and clears a bitmask then returns its old value
- */
-static u16 xgene_word_tst_and_clr(u16 *addr, u16 mask)
-{
- u16 ret, val;
-
- val = le16_to_cpu(READ_ONCE(*addr));
- ret = val & mask;
- val &= ~mask;
- WRITE_ONCE(*addr, cpu_to_le16(val));
-
- return ret;
-}
-
-static int xgene_hwmon_pcc_rd(struct xgene_hwmon_dev *ctx, u32 *msg)
-{
- struct acpi_pcct_shared_memory *generic_comm_base = ctx->pcc_comm_addr;
- u32 *ptr = (void *)(generic_comm_base + 1);
- int rc, i;
- u16 val;
-
- mutex_lock(&ctx->rd_mutex);
- init_completion(&ctx->rd_complete);
- ctx->resp_pending = true;
-
- /* Write signature for subspace */
- WRITE_ONCE(generic_comm_base->signature,
- cpu_to_le32(PCC_SIGNATURE_MASK | ctx->mbox_idx));
-
- /* Write to the shared command region */
- WRITE_ONCE(generic_comm_base->command,
- cpu_to_le16(MSG_TYPE(msg[0]) | PCCC_GENERATE_DB_INT));
-
- /* Flip CMD COMPLETE bit */
- val = le16_to_cpu(READ_ONCE(generic_comm_base->status));
- val &= ~PCCS_CMD_COMPLETE;
- WRITE_ONCE(generic_comm_base->status, cpu_to_le16(val));
-
- /* Copy the message to the PCC comm space */
- for (i = 0; i < sizeof(struct slimpro_resp_msg) / 4; i++)
- WRITE_ONCE(ptr[i], cpu_to_le32(msg[i]));
-
- /* Ring the doorbell */
- rc = mbox_send_message(ctx->mbox_chan, msg);
- if (rc < 0) {
- dev_err(ctx->dev, "Mailbox send error %d\n", rc);
- goto err;
- }
- if (!wait_for_completion_timeout(&ctx->rd_complete,
- usecs_to_jiffies(ctx->usecs_lat))) {
- dev_err(ctx->dev, "Mailbox operation timed out\n");
- rc = -ETIMEDOUT;
- goto err;
- }
-
- /* Check for error message */
- if (MSG_TYPE(ctx->sync_msg.msg) == MSG_TYPE_ERR) {
- rc = -EINVAL;
- goto err;
- }
-
- msg[0] = ctx->sync_msg.msg;
- msg[1] = ctx->sync_msg.param1;
- msg[2] = ctx->sync_msg.param2;
-
-err:
- mbox_chan_txdone(ctx->mbox_chan, 0);
- ctx->resp_pending = false;
- mutex_unlock(&ctx->rd_mutex);
- return rc;
-}
-
-static int xgene_hwmon_rd(struct xgene_hwmon_dev *ctx, u32 *msg)
-{
- int rc;
-
- mutex_lock(&ctx->rd_mutex);
- init_completion(&ctx->rd_complete);
- ctx->resp_pending = true;
-
- rc = mbox_send_message(ctx->mbox_chan, msg);
- if (rc < 0) {
- dev_err(ctx->dev, "Mailbox send error %d\n", rc);
- goto err;
- }
-
- if (!wait_for_completion_timeout(&ctx->rd_complete,
- msecs_to_jiffies(MBOX_OP_TIMEOUTMS))) {
- dev_err(ctx->dev, "Mailbox operation timed out\n");
- rc = -ETIMEDOUT;
- goto err;
- }
-
- /* Check for error message */
- if (MSG_TYPE(ctx->sync_msg.msg) == MSG_TYPE_ERR) {
- rc = -EINVAL;
- goto err;
- }
-
- msg[0] = ctx->sync_msg.msg;
- msg[1] = ctx->sync_msg.param1;
- msg[2] = ctx->sync_msg.param2;
-
-err:
- ctx->resp_pending = false;
- mutex_unlock(&ctx->rd_mutex);
- return rc;
-}
-
-static int xgene_hwmon_reg_map_rd(struct xgene_hwmon_dev *ctx, u32 addr,
- u32 *data)
-{
- u32 msg[3];
- int rc;
-
- msg[0] = SENSOR_RD_MSG;
- msg[1] = SENSOR_RD_EN_ADDR(addr);
- msg[2] = 0;
-
- if (acpi_disabled)
- rc = xgene_hwmon_rd(ctx, msg);
- else
- rc = xgene_hwmon_pcc_rd(ctx, msg);
-
- if (rc < 0)
- return rc;
-
- /*
- * Check if sensor data is valid.
- */
- if (msg[1] & SENSOR_INVALID_DATA)
- return -ENODATA;
-
- *data = msg[1];
-
- return rc;
-}
-
-static int xgene_hwmon_get_notification_msg(struct xgene_hwmon_dev *ctx,
- u32 *amsg)
-{
- u32 msg[3];
- int rc;
-
- msg[0] = TPC_EN_MSG(PWRMGMT_SUBTYPE_TPC, TPC_GET_ALARM, 0);
- msg[1] = 0;
- msg[2] = 0;
-
- rc = xgene_hwmon_pcc_rd(ctx, msg);
- if (rc < 0)
- return rc;
-
- amsg[0] = msg[0];
- amsg[1] = msg[1];
- amsg[2] = msg[2];
-
- return rc;
-}
-
-static int xgene_hwmon_get_cpu_pwr(struct xgene_hwmon_dev *ctx, u32 *val)
-{
- u32 watt, mwatt;
- int rc;
-
- rc = xgene_hwmon_reg_map_rd(ctx, PMD_PWR_REG, &watt);
- if (rc < 0)
- return rc;
-
- rc = xgene_hwmon_reg_map_rd(ctx, PMD_PWR_MW_REG, &mwatt);
- if (rc < 0)
- return rc;
-
- *val = WATT_TO_mWATT(watt) + mwatt;
- return 0;
-}
-
-static int xgene_hwmon_get_io_pwr(struct xgene_hwmon_dev *ctx, u32 *val)
-{
- u32 watt, mwatt;
- int rc;
-
- rc = xgene_hwmon_reg_map_rd(ctx, SOC_PWR_REG, &watt);
- if (rc < 0)
- return rc;
-
- rc = xgene_hwmon_reg_map_rd(ctx, SOC_PWR_MW_REG, &mwatt);
- if (rc < 0)
- return rc;
-
- *val = WATT_TO_mWATT(watt) + mwatt;
- return 0;
-}
-
-static int xgene_hwmon_get_temp(struct xgene_hwmon_dev *ctx, u32 *val)
-{
- return xgene_hwmon_reg_map_rd(ctx, SOC_TEMP_REG, val);
-}
-
-/*
- * Sensor temperature/power functions
- */
-static ssize_t temp1_input_show(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct xgene_hwmon_dev *ctx = dev_get_drvdata(dev);
- int rc, temp;
- u32 val;
-
- rc = xgene_hwmon_get_temp(ctx, &val);
- if (rc < 0)
- return rc;
-
- temp = sign_extend32(val, TEMP_NEGATIVE_BIT);
-
- return sysfs_emit(buf, "%d\n", CELSIUS_TO_mCELSIUS(temp));
-}
-
-static ssize_t temp1_label_show(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- return sysfs_emit(buf, "SoC Temperature\n");
-}
-
-static ssize_t temp1_critical_alarm_show(struct device *dev,
- struct device_attribute *devattr,
- char *buf)
-{
- struct xgene_hwmon_dev *ctx = dev_get_drvdata(dev);
-
- return sysfs_emit(buf, "%d\n", ctx->temp_critical_alarm);
-}
-
-static ssize_t power1_label_show(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- return sysfs_emit(buf, "CPU power\n");
-}
-
-static ssize_t power2_label_show(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- return sysfs_emit(buf, "IO power\n");
-}
-
-static ssize_t power1_input_show(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct xgene_hwmon_dev *ctx = dev_get_drvdata(dev);
- u32 val;
- int rc;
-
- rc = xgene_hwmon_get_cpu_pwr(ctx, &val);
- if (rc < 0)
- return rc;
-
- return sysfs_emit(buf, "%u\n", mWATT_TO_uWATT(val));
-}
-
-static ssize_t power2_input_show(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct xgene_hwmon_dev *ctx = dev_get_drvdata(dev);
- u32 val;
- int rc;
-
- rc = xgene_hwmon_get_io_pwr(ctx, &val);
- if (rc < 0)
- return rc;
-
- return sysfs_emit(buf, "%u\n", mWATT_TO_uWATT(val));
-}
-
-static DEVICE_ATTR_RO(temp1_label);
-static DEVICE_ATTR_RO(temp1_input);
-static DEVICE_ATTR_RO(temp1_critical_alarm);
-static DEVICE_ATTR_RO(power1_label);
-static DEVICE_ATTR_RO(power1_input);
-static DEVICE_ATTR_RO(power2_label);
-static DEVICE_ATTR_RO(power2_input);
-
-static struct attribute *xgene_hwmon_attrs[] = {
- &dev_attr_temp1_label.attr,
- &dev_attr_temp1_input.attr,
- &dev_attr_temp1_critical_alarm.attr,
- &dev_attr_power1_label.attr,
- &dev_attr_power1_input.attr,
- &dev_attr_power2_label.attr,
- &dev_attr_power2_input.attr,
- NULL,
-};
-
-ATTRIBUTE_GROUPS(xgene_hwmon);
-
-static int xgene_hwmon_tpc_alarm(struct xgene_hwmon_dev *ctx,
- struct slimpro_resp_msg *amsg)
-{
- ctx->temp_critical_alarm = !!amsg->param2;
- sysfs_notify(&ctx->dev->kobj, NULL, "temp1_critical_alarm");
-
- return 0;
-}
-
-static void xgene_hwmon_process_pwrmsg(struct xgene_hwmon_dev *ctx,
- struct slimpro_resp_msg *amsg)
-{
- if ((MSG_SUBTYPE(amsg->msg) == PWRMGMT_SUBTYPE_TPC) &&
- (TPC_CMD(amsg->msg) == TPC_ALARM))
- xgene_hwmon_tpc_alarm(ctx, amsg);
-}
-
-/*
- * This function is called to process async work queue
- */
-static void xgene_hwmon_evt_work(struct work_struct *work)
-{
- struct slimpro_resp_msg amsg;
- struct xgene_hwmon_dev *ctx;
- int ret;
-
- ctx = container_of(work, struct xgene_hwmon_dev, workq);
- while (kfifo_out_spinlocked(&ctx->async_msg_fifo, &amsg,
- sizeof(struct slimpro_resp_msg),
- &ctx->kfifo_lock)) {
- /*
- * If PCC, send a consumer command to Platform to get info
- * If Slimpro Mailbox, get message from specific FIFO
- */
- if (!acpi_disabled) {
- ret = xgene_hwmon_get_notification_msg(ctx,
- (u32 *)&amsg);
- if (ret < 0)
- continue;
- }
-
- if (MSG_TYPE(amsg.msg) == MSG_TYPE_PWRMGMT)
- xgene_hwmon_process_pwrmsg(ctx, &amsg);
- }
-}
-
-static int xgene_hwmon_rx_ready(struct xgene_hwmon_dev *ctx, void *msg)
-{
- if (IS_ERR_OR_NULL(ctx->hwmon_dev) && !ctx->resp_pending) {
- /* Enqueue to the FIFO */
- kfifo_in_spinlocked(&ctx->async_msg_fifo, msg,
- sizeof(struct slimpro_resp_msg),
- &ctx->kfifo_lock);
- return -ENODEV;
- }
-
- return 0;
-}
-
-/*
- * This function is called when the SLIMpro Mailbox received a message
- */
-static void xgene_hwmon_rx_cb(struct mbox_client *cl, void *msg)
-{
- struct xgene_hwmon_dev *ctx = to_xgene_hwmon_dev(cl);
-
- /*
- * While the driver registers with the mailbox framework, an interrupt
- * can be pending before the probe function completes its
- * initialization. If such condition occurs, just queue up the message
- * as the driver is not ready for servicing the callback.
- */
- if (xgene_hwmon_rx_ready(ctx, msg) < 0)
- return;
-
- /*
- * Response message format:
- * msg[0] is the return code of the operation
- * msg[1] is the first parameter word
- * msg[2] is the second parameter word
- *
- * As message only supports dword size, just assign it.
- */
-
- /* Check for sync query */
- if (ctx->resp_pending &&
- ((MSG_TYPE(((u32 *)msg)[0]) == MSG_TYPE_ERR) ||
- (MSG_TYPE(((u32 *)msg)[0]) == MSG_TYPE_DBG &&
- MSG_SUBTYPE(((u32 *)msg)[0]) == DBG_SUBTYPE_SENSOR_READ) ||
- (MSG_TYPE(((u32 *)msg)[0]) == MSG_TYPE_PWRMGMT &&
- MSG_SUBTYPE(((u32 *)msg)[0]) == PWRMGMT_SUBTYPE_TPC &&
- TPC_CMD(((u32 *)msg)[0]) == TPC_ALARM))) {
- ctx->sync_msg.msg = ((u32 *)msg)[0];
- ctx->sync_msg.param1 = ((u32 *)msg)[1];
- ctx->sync_msg.param2 = ((u32 *)msg)[2];
-
- /* Operation waiting for response */
- complete(&ctx->rd_complete);
-
- return;
- }
-
- /* Enqueue to the FIFO */
- kfifo_in_spinlocked(&ctx->async_msg_fifo, msg,
- sizeof(struct slimpro_resp_msg), &ctx->kfifo_lock);
- /* Schedule the bottom handler */
- schedule_work(&ctx->workq);
-}
-
-/*
- * This function is called when the PCC Mailbox received a message
- */
-static void xgene_hwmon_pcc_rx_cb(struct mbox_client *cl, void *msg)
-{
- struct xgene_hwmon_dev *ctx = to_xgene_hwmon_dev(cl);
- struct acpi_pcct_shared_memory *generic_comm_base = ctx->pcc_comm_addr;
- struct slimpro_resp_msg amsg;
-
- /*
- * While the driver registers with the mailbox framework, an interrupt
- * can be pending before the probe function completes its
- * initialization. If such condition occurs, just queue up the message
- * as the driver is not ready for servicing the callback.
- */
- if (xgene_hwmon_rx_ready(ctx, &amsg) < 0)
- return;
-
- msg = generic_comm_base + 1;
- /* Check if platform sends interrupt */
- if (!xgene_word_tst_and_clr(&generic_comm_base->status,
- PCCS_SCI_DOORBEL))
- return;
-
- /*
- * Response message format:
- * msg[0] is the return code of the operation
- * msg[1] is the first parameter word
- * msg[2] is the second parameter word
- *
- * As message only supports dword size, just assign it.
- */
-
- /* Check for sync query */
- if (ctx->resp_pending &&
- ((MSG_TYPE(((u32 *)msg)[0]) == MSG_TYPE_ERR) ||
- (MSG_TYPE(((u32 *)msg)[0]) == MSG_TYPE_DBG &&
- MSG_SUBTYPE(((u32 *)msg)[0]) == DBG_SUBTYPE_SENSOR_READ) ||
- (MSG_TYPE(((u32 *)msg)[0]) == MSG_TYPE_PWRMGMT &&
- MSG_SUBTYPE(((u32 *)msg)[0]) == PWRMGMT_SUBTYPE_TPC &&
- TPC_CMD(((u32 *)msg)[0]) == TPC_ALARM))) {
- /* Check if platform completes command */
- if (xgene_word_tst_and_clr(&generic_comm_base->status,
- PCCS_CMD_COMPLETE)) {
- ctx->sync_msg.msg = ((u32 *)msg)[0];
- ctx->sync_msg.param1 = ((u32 *)msg)[1];
- ctx->sync_msg.param2 = ((u32 *)msg)[2];
-
- /* Operation waiting for response */
- complete(&ctx->rd_complete);
-
- return;
- }
- }
-
- /*
- * Platform notifies interrupt to OSPM.
- * OPSM schedules a consumer command to get this information
- * in a workqueue. Platform must wait until OSPM has issued
- * a consumer command that serves this notification.
- */
-
- /* Enqueue to the FIFO */
- kfifo_in_spinlocked(&ctx->async_msg_fifo, &amsg,
- sizeof(struct slimpro_resp_msg), &ctx->kfifo_lock);
- /* Schedule the bottom handler */
- schedule_work(&ctx->workq);
-}
-
-static void xgene_hwmon_tx_done(struct mbox_client *cl, void *msg, int ret)
-{
- if (ret) {
- dev_dbg(cl->dev, "TX did not complete: CMD sent:%x, ret:%d\n",
- *(u16 *)msg, ret);
- } else {
- dev_dbg(cl->dev, "TX completed. CMD sent:%x, ret:%d\n",
- *(u16 *)msg, ret);
- }
-}
-
-#ifdef CONFIG_ACPI
-static const struct acpi_device_id xgene_hwmon_acpi_match[] = {
- {"APMC0D29", XGENE_HWMON_V1},
- {"APMC0D8A", XGENE_HWMON_V2},
- {},
-};
-MODULE_DEVICE_TABLE(acpi, xgene_hwmon_acpi_match);
-#endif
-
-static int xgene_hwmon_probe(struct platform_device *pdev)
-{
- struct xgene_hwmon_dev *ctx;
- struct mbox_client *cl;
- int rc;
-
- ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
- if (!ctx)
- return -ENOMEM;
-
- ctx->dev = &pdev->dev;
- platform_set_drvdata(pdev, ctx);
- cl = &ctx->mbox_client;
-
- spin_lock_init(&ctx->kfifo_lock);
- mutex_init(&ctx->rd_mutex);
-
- rc = kfifo_alloc(&ctx->async_msg_fifo,
- sizeof(struct slimpro_resp_msg) * ASYNC_MSG_FIFO_SIZE,
- GFP_KERNEL);
- if (rc)
- return -ENOMEM;
-
- INIT_WORK(&ctx->workq, xgene_hwmon_evt_work);
-
- /* Request mailbox channel */
- cl->dev = &pdev->dev;
- cl->tx_done = xgene_hwmon_tx_done;
- cl->tx_block = false;
- cl->tx_tout = MBOX_OP_TIMEOUTMS;
- cl->knows_txdone = false;
- if (acpi_disabled) {
- cl->rx_callback = xgene_hwmon_rx_cb;
- ctx->mbox_chan = mbox_request_channel(cl, 0);
- if (IS_ERR(ctx->mbox_chan)) {
- dev_err(&pdev->dev,
- "SLIMpro mailbox channel request failed\n");
- rc = -ENODEV;
- goto out_mbox_free;
- }
- } else {
- struct pcc_mbox_chan *pcc_chan;
- const struct acpi_device_id *acpi_id;
- int version;
-
- acpi_id = acpi_match_device(pdev->dev.driver->acpi_match_table,
- &pdev->dev);
- if (!acpi_id) {
- rc = -EINVAL;
- goto out_mbox_free;
- }
-
- version = (int)acpi_id->driver_data;
-
- if (device_property_read_u32(&pdev->dev, "pcc-channel",
- &ctx->mbox_idx)) {
- dev_err(&pdev->dev, "no pcc-channel property\n");
- rc = -ENODEV;
- goto out_mbox_free;
- }
-
- cl->rx_callback = xgene_hwmon_pcc_rx_cb;
- pcc_chan = pcc_mbox_request_channel(cl, ctx->mbox_idx);
- if (IS_ERR(pcc_chan)) {
- dev_err(&pdev->dev,
- "PPC channel request failed\n");
- rc = -ENODEV;
- goto out_mbox_free;
- }
-
- ctx->pcc_chan = pcc_chan;
- ctx->mbox_chan = pcc_chan->mchan;
-
- if (!ctx->mbox_chan->mbox->txdone_irq) {
- dev_err(&pdev->dev, "PCC IRQ not supported\n");
- rc = -ENODEV;
- goto out;
- }
-
- /*
- * This is the shared communication region
- * for the OS and Platform to communicate over.
- */
- ctx->comm_base_addr = pcc_chan->shmem_base_addr;
- if (ctx->comm_base_addr) {
- if (version == XGENE_HWMON_V2)
- ctx->pcc_comm_addr = (void __force *)ioremap(
- ctx->comm_base_addr,
- pcc_chan->shmem_size);
- else
- ctx->pcc_comm_addr = memremap(
- ctx->comm_base_addr,
- pcc_chan->shmem_size,
- MEMREMAP_WB);
- } else {
- dev_err(&pdev->dev, "Failed to get PCC comm region\n");
- rc = -ENODEV;
- goto out;
- }
-
- if (!ctx->pcc_comm_addr) {
- dev_err(&pdev->dev,
- "Failed to ioremap PCC comm region\n");
- rc = -ENOMEM;
- goto out;
- }
-
- /*
- * pcc_chan->latency is just a Nominal value. In reality
- * the remote processor could be much slower to reply.
- * So add an arbitrary amount of wait on top of Nominal.
- */
- ctx->usecs_lat = PCC_NUM_RETRIES * pcc_chan->latency;
- }
-
- ctx->hwmon_dev = hwmon_device_register_with_groups(ctx->dev,
- "apm_xgene",
- ctx,
- xgene_hwmon_groups);
- if (IS_ERR(ctx->hwmon_dev)) {
- dev_err(&pdev->dev, "Failed to register HW monitor device\n");
- rc = PTR_ERR(ctx->hwmon_dev);
- goto out;
- }
-
- /*
- * Schedule the bottom handler if there is a pending message.
- */
- schedule_work(&ctx->workq);
-
- dev_info(&pdev->dev, "APM X-Gene SoC HW monitor driver registered\n");
-
- return 0;
-
-out:
- if (acpi_disabled)
- mbox_free_channel(ctx->mbox_chan);
- else
- pcc_mbox_free_channel(ctx->pcc_chan);
-out_mbox_free:
- kfifo_free(&ctx->async_msg_fifo);
-
- return rc;
-}
-
-static int xgene_hwmon_remove(struct platform_device *pdev)
-{
- struct xgene_hwmon_dev *ctx = platform_get_drvdata(pdev);
-
- hwmon_device_unregister(ctx->hwmon_dev);
- kfifo_free(&ctx->async_msg_fifo);
- if (acpi_disabled)
- mbox_free_channel(ctx->mbox_chan);
- else
- pcc_mbox_free_channel(ctx->pcc_chan);
-
- return 0;
-}
-
-static const struct of_device_id xgene_hwmon_of_match[] = {
- {.compatible = "apm,xgene-slimpro-hwmon"},
- {}
-};
-MODULE_DEVICE_TABLE(of, xgene_hwmon_of_match);
-
-static struct platform_driver xgene_hwmon_driver = {
- .probe = xgene_hwmon_probe,
- .remove = xgene_hwmon_remove,
- .driver = {
- .name = "xgene-slimpro-hwmon",
- .of_match_table = xgene_hwmon_of_match,
- .acpi_match_table = ACPI_PTR(xgene_hwmon_acpi_match),
- },
-};
-module_platform_driver(xgene_hwmon_driver);
-
-MODULE_DESCRIPTION("APM X-Gene SoC hardware monitor");
-MODULE_LICENSE("GPL");
--
2.35.1