path: root/drivers/hid/intel-ish-hid/ipc/ipc.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * H/W layer of ISHTP provider device (ISH)
 *
 * Copyright (c) 2014-2016, Intel Corporation.
 */

#include <linux/devm-helpers.h>
#include <linux/sched.h>
#include <linux/spinlock.h>
#include <linux/delay.h>
#include <linux/jiffies.h>
#include "client.h"
#include "hw-ish.h"
#include "hbm.h"

/* For FW reset flow */
static struct work_struct fw_reset_work;
static struct ishtp_device *ishtp_dev;

/**
 * ish_reg_read() - Read register
 * @dev: ISHTP device pointer
 * @offset: Register offset
 *
 * Read 32 bit register at a given offset
 *
 * Return: Read register value
 */
static inline uint32_t ish_reg_read(const struct ishtp_device *dev,
	unsigned long offset)
{
	struct ish_hw *hw = to_ish_hw(dev);

	return readl(hw->mem_addr + offset);
}

/**
 * ish_reg_write() - Write register
 * @dev: ISHTP device pointer
 * @offset: Register offset
 * @value: Value to write
 *
 * Writes 32 bit register at a give offset
 */
static inline void ish_reg_write(struct ishtp_device *dev,
				 unsigned long offset,
				 uint32_t value)
{
	struct ish_hw *hw = to_ish_hw(dev);

	writel(value, hw->mem_addr + offset);
}

/**
 * _ish_read_fw_sts_reg() - Read FW status register
 * @dev: ISHTP device pointer
 *
 * Read FW status register
 *
 * Return: Read register value
 */
static inline uint32_t _ish_read_fw_sts_reg(struct ishtp_device *dev)
{
	return ish_reg_read(dev, IPC_REG_ISH_HOST_FWSTS);
}

/**
 * check_generated_interrupt() - Check if ISH interrupt
 * @dev: ISHTP device pointer
 *
 * Check if an interrupt was generated for ISH
 *
 * Return: Read true or false
 */
static bool check_generated_interrupt(struct ishtp_device *dev)
{
	bool interrupt_generated = true;
	uint32_t pisr_val = 0;

	if (dev->pdev->device == PCI_DEVICE_ID_INTEL_ISH_CHV) {
		pisr_val = ish_reg_read(dev, IPC_REG_PISR_CHV_AB);
		interrupt_generated =
			IPC_INT_FROM_ISH_TO_HOST_CHV_AB(pisr_val);
	} else {
		pisr_val = ish_reg_read(dev, IPC_REG_PISR_BXT);
		interrupt_generated = !!pisr_val;
		/* only busy-clear bit is RW, others are RO */
		if (pisr_val)
			ish_reg_write(dev, IPC_REG_PISR_BXT, pisr_val);
	}

	return interrupt_generated;
}

/**
 * ish_is_input_ready() - Check if FW ready for RX
 * @dev: ISHTP device pointer
 *
 * Check if ISH FW is ready for receiving data
 *
 * Return: Read true or false
 */
static bool ish_is_input_ready(struct ishtp_device *dev)
{
	uint32_t doorbell_val;

	doorbell_val = ish_reg_read(dev, IPC_REG_HOST2ISH_DRBL);
	return !IPC_IS_BUSY(doorbell_val);
}

/**
 * set_host_ready() - Indicate host ready
 * @dev: ISHTP device pointer
 *
 * Set host ready indication to FW
 */
static void set_host_ready(struct ishtp_device *dev)
{
	if (dev->pdev->device == PCI_DEVICE_ID_INTEL_ISH_CHV) {
		if (dev->pdev->revision == REVISION_ID_CHT_A0 ||
				(dev->pdev->revision & REVISION_ID_SI_MASK) ==
				REVISION_ID_CHT_Ax_SI)
			ish_reg_write(dev, IPC_REG_HOST_COMM, 0x81);
		else if (dev->pdev->revision == REVISION_ID_CHT_B0 ||
				(dev->pdev->revision & REVISION_ID_SI_MASK) ==
				REVISION_ID_CHT_Bx_SI ||
				(dev->pdev->revision & REVISION_ID_SI_MASK) ==
				REVISION_ID_CHT_Kx_SI ||
				(dev->pdev->revision & REVISION_ID_SI_MASK) ==
				REVISION_ID_CHT_Dx_SI) {
			uint32_t host_comm_val;

			host_comm_val = ish_reg_read(dev, IPC_REG_HOST_COMM);
			host_comm_val |= IPC_HOSTCOMM_INT_EN_BIT_CHV_AB | 0x81;
			ish_reg_write(dev, IPC_REG_HOST_COMM, host_comm_val);
		}
	} else {
			uint32_t host_pimr_val;

			host_pimr_val = ish_reg_read(dev, IPC_REG_PIMR_BXT);
			host_pimr_val |= IPC_PIMR_INT_EN_BIT_BXT;
			/*
			 * disable interrupt generated instead of
			 * RX_complete_msg
			 */
			host_pimr_val &= ~IPC_HOST2ISH_BUSYCLEAR_MASK_BIT;

			ish_reg_write(dev, IPC_REG_PIMR_BXT, host_pimr_val);
	}
}

/**
 * ishtp_fw_is_ready() - Check if FW ready
 * @dev: ISHTP device pointer
 *
 * Check if ISH FW is ready
 *
 * Return: Read true or false
 */
static bool ishtp_fw_is_ready(struct ishtp_device *dev)
{
	uint32_t ish_status = _ish_read_fw_sts_reg(dev);

	return IPC_IS_ISH_ILUP(ish_status) &&
		IPC_IS_ISH_ISHTP_READY(ish_status);
}

/**
 * ish_set_host_rdy() - Indicate host ready
 * @dev: ISHTP device pointer
 *
 * Set host ready indication to FW
 */
static void ish_set_host_rdy(struct ishtp_device *dev)
{
	uint32_t