[PATCH v3 2/3] hwmon: xgene: Add hwmon driver

Hoan Tran
2016-07-21T20:55:56Z

This patch adds hardware temperature and power reading support for
APM X-Gene SoC using the mailbox communication interface.

Signed-off-by: Hoan Tran <hotran@apm.com>
---
Documentation/hwmon/xgene-hwmon | 30 ++
drivers/hwmon/Kconfig | 7 +
drivers/hwmon/Makefile | 1 +
drivers/hwmon/xgene-hwmon.c | 755 ++++++++++++++++++++++++++++++++++++++++
4 files changed, 793 insertions(+)
create mode 100644 Documentation/hwmon/xgene-hwmon
create mode 100644 drivers/hwmon/xgene-hwmon.c

diff --git a/Documentation/hwmon/xgene-hwmon b/Documentation/hwmon/xgene-hwmon
new file mode 100644
index 0000000..6ec50ed
--- /dev/null
+++ b/Documentation/hwmon/xgene-hwmon
@@ -0,0 +1,30 @@
+Kernel driver xgene-hwmon
+========================
+
+Supported chips:
+ * APM X-Gene SoC
+
+Description
+-----------
+
+This driver adds hardware temperature and power reading support for
+APM X-Gene SoC using the mailbox communication interface.
+For device tree, it is the standard DT mailbox.
+For ACPI, it is the PCC mailbox.
+
+The following sensors are supported
+
+ * Temperature
+ - SoC on-die temperature in milli-degree C
+ - Alarm when high/over temperature occurs
+ * Power
+ - CPU power in uW
+ - IO power in uW
+
+sysfs-Interface
+---------------
+
+temp0_input - SoC on-die temperature (milli-degree C)
+temp0_critical_alarm - An 1 would indicates on-die temperature exceeded threshold
+power0_input - CPU power in (uW)
+power1_input - IO power in (uW)
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index ff94007..55218c6 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1787,6 +1787,13 @@ 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.
+
if ACPI

comment "ACPI drivers"
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 2ef5b7c..a2460dd 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -162,6 +162,7 @@ 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_PMBUS) += pmbus/

diff --git a/drivers/hwmon/xgene-hwmon.c b/drivers/hwmon/xgene-hwmon.c
new file mode 100644
index 0000000..c263e7e
--- /dev/null
+++ b/drivers/hwmon/xgene-hwmon.c
@@ -0,0 +1,755 @@
+/*
+ * APM X-Gene SoC Hardware Monitoring Driver
+ *
+ * Copyright (c) 2016, Applied Micro Circuits Corporation
+ * Author: Loc Ho <lho@apm.com>
+ * Hoan Tran <hotran@apm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ *
+ * 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/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/acpi_io.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)
+
+struct slimpro_resp_msg {
+ u32 msg;
+ u32 param1;
+ u32 param2;
+} __packed;
+
+struct xgene_hwmon_dev {
+ struct device *dev;
+ struct mbox_chan *mbox_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 = readw_relaxed(addr);
+ ret = val & mask;
+ val &= ~mask;
+ writew_relaxed(val, addr);
+
+ 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;
+ void *ptr = 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 */
+ writel_relaxed(PCC_SIGNATURE_MASK | ctx->mbox_idx,
+ &generic_comm_base->signature);
+
+ /* Write to the shared command region */
+ writew_relaxed(MSG_TYPE(msg[0]) | PCCC_GENERATE_DB_INT,
+ &generic_comm_base->command);
+
+ /* Flip CMD COMPLETE bit */
+ val = readw_relaxed(&generic_comm_base->status);
+ val &= ~PCCS_CMD_COMPLETE;
+ writew_relaxed(val, &generic_comm_base->status);
+
+ /* Copy the message to the PCC comm space */
+ for (i = 0; i < sizeof(struct slimpro_resp_msg) / 4; i++)
+ writel_relaxed(msg[i], ptr + i * 4);
+
+ /* 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 snprintf(buf, PAGE_SIZE, "%d\n", CELSIUS_TO_mCELSIUS(temp));
+}
+
+static ssize_t temp1_label_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "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 snprintf(buf, PAGE_SIZE, "%d\n", ctx->temp_critical_alarm);
+}
+
+static ssize_t power1_label_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "CPU power\n");
+}
+
+static ssize_t power2_label_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "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 snprintf(buf, PAGE_SIZE, "%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 snprintf(buf, PAGE_SIZE, "%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);
+ }
+}
+
+/*
+ * 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);
+ struct slimpro_resp_msg amsg;
+
+ /*
+ * 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;
+ }
+
+ amsg.msg = ((u32 *)msg)[0];
+ amsg.param1 = ((u32 *)msg)[1];
+ amsg.param2 = ((u32 *)msg)[2];
+
+ /* 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);
+}
+
+/*
+ * 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;
+
+ 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);
+ }
+}
+
+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;
+
+ /* 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");
+ return -ENODEV;
+ }
+ } else {
+ struct acpi_pcct_hw_reduced *cppc_ss;
+
+ if (device_property_read_u32(&pdev->dev, "pcc-channel",
+ &ctx->mbox_idx)) {
+ dev_err(&pdev->dev, "no pcc-channel property\n");
+ return -ENODEV;
+ }
+
+ cl->rx_callback = xgene_hwmon_pcc_rx_cb;
+ ctx->mbox_chan = pcc_mbox_request_channel(cl, ctx->mbox_idx);
+ if (IS_ERR(ctx->mbox_chan)) {
+ dev_err(&pdev->dev,
+ "PPC channel request failed\n");
+ return -ENODEV;
+ }
+
+ /*
+ * The PCC mailbox controller driver should
+ * have parsed the PCCT (global table of all
+ * PCC channels) and stored pointers to the
+ * subspace communication region in con_priv.
+ */
+ cppc_ss = ctx->mbox_chan->con_priv;
+ if (!cppc_ss) {
+ dev_err(&pdev->dev, "PPC subspace not found\n");
+ rc = -ENODEV;
+ goto out_mbox_free;
+ }
+
+ if (!ctx->mbox_chan->mbox->txdone_irq) {
+ dev_err(&pdev->dev, "PCC IRQ not supported\n");
+ rc = -ENODEV;
+ goto out_mbox_free;
+ }
+
+ /*
+ * This is the shared communication region
+ * for the OS and Platform to communicate over.
+ */
+ ctx->comm_base_addr = cppc_ss->base_address;
+ if (ctx->comm_base_addr) {
+ ctx->pcc_comm_addr =
+ acpi_os_ioremap(ctx->comm_base_addr,
+ cppc_ss->length);
+ } else {
+ dev_err(&pdev->dev, "Failed to get PCC comm region\n");
+ rc = -ENODEV;
+ goto out_mbox_free;
+ }
+
+ if (!ctx->pcc_comm_addr) {
+ dev_err(&pdev->dev,
+ "Failed to ioremap PCC comm region\n");
+ rc = -ENOMEM;
+ goto out_mbox_free;
+ }
+
+ /*
+ * cppc_ss->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 * cppc_ss->latency;
+ }
+
+ 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)
+ goto out_mbox_free;
+
+ INIT_WORK(&ctx->workq, xgene_hwmon_evt_work);
+
+ 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;
+ }
+
+ dev_info(&pdev->dev, "APM X-Gene SoC HW monitor driver registered\n");
+
+ return rc;
+
+out:
+ kfifo_free(&ctx->async_msg_fifo);
+out_mbox_free:
+ if (acpi_disabled)
+ mbox_free_channel(ctx->mbox_chan);
+ else
+ pcc_mbox_free_channel(ctx->mbox_chan);
+
+ 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->mbox_chan);
+
+ return 0;
+}
+
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id xgene_hwmon_acpi_match[] = {
+ {"APMC0D29", 0},
+ {},
+};
+MODULE_DEVICE_TABLE(acpi, xgene_hwmon_acpi_match);
+#endif
+
+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 __refdata = {
+ .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");
--
1.9.1