diff options
Diffstat (limited to 'drivers/hwmon/xgene-hwmon.c')
-rw-r--r-- | drivers/hwmon/xgene-hwmon.c | 793 |
1 files changed, 793 insertions, 0 deletions
diff --git a/drivers/hwmon/xgene-hwmon.c b/drivers/hwmon/xgene-hwmon.c new file mode 100644 index 000000000..78d9f52e2 --- /dev/null +++ b/drivers/hwmon/xgene-hwmon.c @@ -0,0 +1,793 @@ +// 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@apm.com> + * Hoan Tran <hotran@apm.com> + * + * 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 *)devm_ioremap(&pdev->dev, + ctx->comm_base_addr, + pcc_chan->shmem_size); + else + ctx->pcc_comm_addr = devm_memremap(&pdev->dev, + 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); + + cancel_work_sync(&ctx->workq); + 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"); |