linux/drivers/misc/mei/gsc-me.c
Tomas Winkler 0995c95b08 mei: gsc: add module description
For completeness add gsc module description.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20230716081043.3092690-4-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-30 18:15:53 +02:00

317 lines
6.9 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright(c) 2019-2022, Intel Corporation. All rights reserved.
*
* Intel Management Engine Interface (Intel MEI) Linux driver
*/
#include <linux/module.h>
#include <linux/mei_aux.h>
#include <linux/device.h>
#include <linux/irqreturn.h>
#include <linux/jiffies.h>
#include <linux/ktime.h>
#include <linux/delay.h>
#include <linux/pm_runtime.h>
#include <linux/kthread.h>
#include "mei_dev.h"
#include "hw-me.h"
#include "hw-me-regs.h"
#include "mei-trace.h"
#define MEI_GSC_RPM_TIMEOUT 500
static int mei_gsc_read_hfs(const struct mei_device *dev, int where, u32 *val)
{
struct mei_me_hw *hw = to_me_hw(dev);
*val = ioread32(hw->mem_addr + where + 0xC00);
return 0;
}
static void mei_gsc_set_ext_op_mem(const struct mei_me_hw *hw, struct resource *mem)
{
u32 low = lower_32_bits(mem->start);
u32 hi = upper_32_bits(mem->start);
u32 limit = (resource_size(mem) / SZ_4K) | GSC_EXT_OP_MEM_VALID;
iowrite32(low, hw->mem_addr + H_GSC_EXT_OP_MEM_BASE_ADDR_LO_REG);
iowrite32(hi, hw->mem_addr + H_GSC_EXT_OP_MEM_BASE_ADDR_HI_REG);
iowrite32(limit, hw->mem_addr + H_GSC_EXT_OP_MEM_LIMIT_REG);
}
static int mei_gsc_probe(struct auxiliary_device *aux_dev,
const struct auxiliary_device_id *aux_dev_id)
{
struct mei_aux_device *adev = auxiliary_dev_to_mei_aux_dev(aux_dev);
struct mei_device *dev;
struct mei_me_hw *hw;
struct device *device;
const struct mei_cfg *cfg;
int ret;
cfg = mei_me_get_cfg(aux_dev_id->driver_data);
if (!cfg)
return -ENODEV;
device = &aux_dev->dev;
dev = mei_me_dev_init(device, cfg, adev->slow_firmware);
if (!dev) {
ret = -ENOMEM;
goto err;
}
hw = to_me_hw(dev);
hw->mem_addr = devm_ioremap_resource(device, &adev->bar);
if (IS_ERR(hw->mem_addr)) {
ret = PTR_ERR(hw->mem_addr);
goto err;
}
hw->irq = adev->irq;
hw->read_fws = mei_gsc_read_hfs;
dev_set_drvdata(device, dev);
if (adev->ext_op_mem.start) {
mei_gsc_set_ext_op_mem(hw, &adev->ext_op_mem);
dev->pxp_mode = MEI_DEV_PXP_INIT;
}
/* use polling */
if (mei_me_hw_use_polling(hw)) {
mei_disable_interrupts(dev);
mei_clear_interrupts(dev);
init_waitqueue_head(&hw->wait_active);
hw->is_active = true; /* start in active mode for initialization */
hw->polling_thread = kthread_run(mei_me_polling_thread, dev,
"kmegscirqd/%s", dev_name(device));
if (IS_ERR(hw->polling_thread)) {
ret = PTR_ERR(hw->polling_thread);
dev_err(device, "unable to create kernel thread: %d\n", ret);
goto err;
}
} else {
ret = devm_request_threaded_irq(device, hw->irq,
mei_me_irq_quick_handler,
mei_me_irq_thread_handler,
IRQF_ONESHOT, KBUILD_MODNAME, dev);
if (ret) {
dev_err(device, "irq register failed %d\n", ret);
goto err;
}
}
pm_runtime_get_noresume(device);
pm_runtime_set_active(device);
pm_runtime_enable(device);
/* Continue to char device setup in spite of firmware handshake failure.
* In order to provide access to the firmware status registers to the user
* space via sysfs.
*/
if (mei_start(dev))
dev_warn(device, "init hw failure.\n");
pm_runtime_set_autosuspend_delay(device, MEI_GSC_RPM_TIMEOUT);
pm_runtime_use_autosuspend(device);
ret = mei_register(dev, device);
if (ret)
goto register_err;
pm_runtime_put_noidle(device);
return 0;
register_err:
mei_stop(dev);
if (!mei_me_hw_use_polling(hw))
devm_free_irq(device, hw->irq, dev);
err:
dev_err(device, "probe failed: %d\n", ret);
dev_set_drvdata(device, NULL);
return ret;
}
static void mei_gsc_remove(struct auxiliary_device *aux_dev)
{
struct mei_device *dev;
struct mei_me_hw *hw;
dev = dev_get_drvdata(&aux_dev->dev);
if (!dev)
return;
hw = to_me_hw(dev);
mei_stop(dev);
hw = to_me_hw(dev);
if (mei_me_hw_use_polling(hw))
kthread_stop(hw->polling_thread);
mei_deregister(dev);
pm_runtime_disable(&aux_dev->dev);
mei_disable_interrupts(dev);
if (!mei_me_hw_use_polling(hw))
devm_free_irq(&aux_dev->dev, hw->irq, dev);
}
static int __maybe_unused mei_gsc_pm_suspend(struct device *device)
{
struct mei_device *dev = dev_get_drvdata(device);
if (!dev)
return -ENODEV;
mei_stop(dev);
mei_disable_interrupts(dev);
return 0;
}
static int __maybe_unused mei_gsc_pm_resume(struct device *device)
{
struct mei_device *dev = dev_get_drvdata(device);
struct auxiliary_device *aux_dev;
struct mei_aux_device *adev;
int err;
struct mei_me_hw *hw;
if (!dev)
return -ENODEV;
hw = to_me_hw(dev);
aux_dev = to_auxiliary_dev(device);
adev = auxiliary_dev_to_mei_aux_dev(aux_dev);
if (adev->ext_op_mem.start) {
mei_gsc_set_ext_op_mem(hw, &adev->ext_op_mem);
dev->pxp_mode = MEI_DEV_PXP_INIT;
}
err = mei_restart(dev);
if (err)
return err;
/* Start timer if stopped in suspend */
schedule_delayed_work(&dev->timer_work, HZ);
return 0;
}
static int __maybe_unused mei_gsc_pm_runtime_idle(struct device *device)
{
struct mei_device *dev = dev_get_drvdata(device);
if (!dev)
return -ENODEV;
if (mei_write_is_idle(dev))
pm_runtime_autosuspend(device);
return -EBUSY;
}
static int __maybe_unused mei_gsc_pm_runtime_suspend(struct device *device)
{
struct mei_device *dev = dev_get_drvdata(device);
struct mei_me_hw *hw;
int ret;
if (!dev)
return -ENODEV;
mutex_lock(&dev->device_lock);
if (mei_write_is_idle(dev)) {
hw = to_me_hw(dev);
hw->pg_state = MEI_PG_ON;
if (mei_me_hw_use_polling(hw))
hw->is_active = false;
ret = 0;
} else {
ret = -EAGAIN;
}
mutex_unlock(&dev->device_lock);
return ret;
}
static int __maybe_unused mei_gsc_pm_runtime_resume(struct device *device)
{
struct mei_device *dev = dev_get_drvdata(device);
struct mei_me_hw *hw;
irqreturn_t irq_ret;
if (!dev)
return -ENODEV;
mutex_lock(&dev->device_lock);
hw = to_me_hw(dev);
hw->pg_state = MEI_PG_OFF;
if (mei_me_hw_use_polling(hw)) {
hw->is_active = true;
wake_up(&hw->wait_active);
}
mutex_unlock(&dev->device_lock);
irq_ret = mei_me_irq_thread_handler(1, dev);
if (irq_ret != IRQ_HANDLED)
dev_err(dev->dev, "thread handler fail %d\n", irq_ret);
return 0;
}
static const struct dev_pm_ops mei_gsc_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(mei_gsc_pm_suspend,
mei_gsc_pm_resume)
SET_RUNTIME_PM_OPS(mei_gsc_pm_runtime_suspend,
mei_gsc_pm_runtime_resume,
mei_gsc_pm_runtime_idle)
};
static const struct auxiliary_device_id mei_gsc_id_table[] = {
{
.name = "i915.mei-gsc",
.driver_data = MEI_ME_GSC_CFG,
},
{
.name = "i915.mei-gscfi",
.driver_data = MEI_ME_GSCFI_CFG,
},
{
/* sentinel */
}
};
MODULE_DEVICE_TABLE(auxiliary, mei_gsc_id_table);
static struct auxiliary_driver mei_gsc_driver = {
.probe = mei_gsc_probe,
.remove = mei_gsc_remove,
.driver = {
/* auxiliary_driver_register() sets .name to be the modname */
.pm = &mei_gsc_pm_ops,
},
.id_table = mei_gsc_id_table
};
module_auxiliary_driver(mei_gsc_driver);
MODULE_AUTHOR("Intel Corporation");
MODULE_ALIAS("auxiliary:i915.mei-gsc");
MODULE_ALIAS("auxiliary:i915.mei-gscfi");
MODULE_DESCRIPTION("Intel(R) Graphics System Controller");
MODULE_LICENSE("GPL");