1 files changed, 315 insertions, 0 deletions
diff --git a/drivers/misc/mei/gsc-me.c b/drivers/misc/mei/gsc-me.c
new file mode 100644
index 000000000..e63cabd08
--- /dev/null
+++ b/drivers/misc/mei/gsc-me.c
@@ -0,0 +1,315 @@
+// 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_LICENSE("GPL");