net: wwan: t7xx: Add control DMA interface

Cross Layer DMA (CLDMA) Hardware interface (HIF) enables the control
path of Host-Modem data transfers. CLDMA HIF layer provides a common
interface to the Port Layer.

CLDMA manages 8 independent RX/TX physical channels with data flow
control in HW queues. CLDMA uses ring buffers of General Packet
Descriptors (GPD) for TX/RX. GPDs can represent multiple or single
data buffers (DB).

CLDMA HIF initializes GPD rings, registers ISR handlers for CLDMA
interrupts, and initializes CLDMA HW registers.

CLDMA TX flow:
1. Port Layer write
2. Get DB address
3. Configure GPD
4. Triggering processing via HW register write

CLDMA RX flow:
1. CLDMA HW sends a RX "done" to host
2. Driver starts thread to safely read GPD
3. DB is sent to Port layer
4. Create a new buffer for GPD ring

Note: This patch does not enable compilation since it has dependencies
such as t7xx_pcie_mac_clear_int()/t7xx_pcie_mac_set_int() and
struct t7xx_pci_dev which are added by the core patch.

Signed-off-by: Haijun Liu <[e-mail]>
Signed-off-by: Chandrashekar Devegowda <[e-mail]>
Co-developed-by: Ricardo Martinez <[e-mail]>
Signed-off-by: Ricardo Martinez <[e-mail]>
Reviewed-by: Loic Poulain <[e-mail]>
Reviewed-by: Ilpo Järvinen <[e-mail]>
Reviewed-by: Sergey Ryazanov <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

drivers/net/wwan/t7xx/t7xx_cldma.c

···
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2021, MediaTek Inc.
+ * Copyright (c) 2021-2022, Intel Corporation.
+ *
+ * Authors:
+ *  Haijun Liu <[e-mail]>
+ *  Moises Veleta <[e-mail]>
+ *  Ricardo Martinez <[e-mail]>
+ *
+ * Contributors:
+ *  Amir Hanania <[e-mail]>
+ *  Andy Shevchenko <[e-mail]>
+ *  Eliot Lee <[e-mail]>
+ *  Sreehari Kancharla <[e-mail]>
+ */
+
+#include <linux/bits.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/io-64-nonatomic-lo-hi.h>
+#include <linux/types.h>
+
+#include "t7xx_cldma.h"
+
+#define ADDR_SIZE	8
+
+void t7xx_cldma_clear_ip_busy(struct t7xx_cldma_hw *hw_info)
+{
+	u32 val;
+
+	val = ioread32(hw_info->ap_pdn_base + REG_CLDMA_IP_BUSY);
+	val |= IP_BUSY_WAKEUP;
+	iowrite32(val, hw_info->ap_pdn_base + REG_CLDMA_IP_BUSY);
+}
+
+/**
+ * t7xx_cldma_hw_restore() - Restore CLDMA HW registers.
+ * @hw_info: Pointer to struct t7xx_cldma_hw.
+ *
+ * Restore HW after resume. Writes uplink configuration for CLDMA HW.
+ */
+void t7xx_cldma_hw_restore(struct t7xx_cldma_hw *hw_info)
+{
+	u32 ul_cfg;
+
+	ul_cfg = ioread32(hw_info->ap_pdn_base + REG_CLDMA_UL_CFG);
+	ul_cfg &= ~UL_CFG_BIT_MODE_MASK;
+
+	if (hw_info->hw_mode == MODE_BIT_64)
+		ul_cfg |= UL_CFG_BIT_MODE_64;
+	else if (hw_info->hw_mode == MODE_BIT_40)
+		ul_cfg |= UL_CFG_BIT_MODE_40;
+	else if (hw_info->hw_mode == MODE_BIT_36)
+		ul_cfg |= UL_CFG_BIT_MODE_36;
+
+	iowrite32(ul_cfg, hw_info->ap_pdn_base + REG_CLDMA_UL_CFG);
+	/* Disable TX and RX invalid address check */
+	iowrite32(UL_MEM_CHECK_DIS, hw_info->ap_pdn_base + REG_CLDMA_UL_MEM);
+	iowrite32(DL_MEM_CHECK_DIS, hw_info->ap_pdn_base + REG_CLDMA_DL_MEM);
+}
+
+void t7xx_cldma_hw_start_queue(struct t7xx_cldma_hw *hw_info, unsigned int qno,
+			       enum mtk_txrx tx_rx)
+{
+	void __iomem *reg;
+	u32 val;
+
+	reg = tx_rx == MTK_RX ? hw_info->ap_pdn_base + REG_CLDMA_DL_START_CMD :
+				hw_info->ap_pdn_base + REG_CLDMA_UL_START_CMD;
+	val = qno == CLDMA_ALL_Q ? CLDMA_ALL_Q : BIT(qno);
+	iowrite32(val, reg);
+}
+
+void t7xx_cldma_hw_start(struct t7xx_cldma_hw *hw_info)
+{
+	/* Enable the TX & RX interrupts */
+	iowrite32(TXRX_STATUS_BITMASK, hw_info->ap_pdn_base + REG_CLDMA_L2TIMCR0);
+	iowrite32(TXRX_STATUS_BITMASK, hw_info->ap_ao_base + REG_CLDMA_L2RIMCR0);
+	/* Enable the empty queue interrupt */
+	iowrite32(EMPTY_STATUS_BITMASK, hw_info->ap_pdn_base + REG_CLDMA_L2TIMCR0);
+	iowrite32(EMPTY_STATUS_BITMASK, hw_info->ap_ao_base + REG_CLDMA_L2RIMCR0);
+}
+
+void t7xx_cldma_hw_reset(void __iomem *ao_base)
+{
+	u32 val;
+
+	val = ioread32(ao_base + REG_INFRA_RST2_SET);
+	val |= RST2_PMIC_SW_RST_SET;
+	iowrite32(val, ao_base + REG_INFRA_RST2_SET);
+	val = ioread32(ao_base + REG_INFRA_RST4_SET);
+	val |= RST4_CLDMA1_SW_RST_SET;
+	iowrite32(val, ao_base + REG_INFRA_RST4_SET);
+	udelay(1);
+
+	val = ioread32(ao_base + REG_INFRA_RST4_CLR);
+	val |= RST4_CLDMA1_SW_RST_CLR;
+	iowrite32(val, ao_base + REG_INFRA_RST4_CLR);
+	val = ioread32(ao_base + REG_INFRA_RST2_CLR);
+	val |= RST2_PMIC_SW_RST_CLR;
+	iowrite32(val, ao_base + REG_INFRA_RST2_CLR);
+}
+
+bool t7xx_cldma_tx_addr_is_set(struct t7xx_cldma_hw *hw_info, unsigned int qno)
+{
+	u32 offset = REG_CLDMA_UL_START_ADDRL_0 + qno * ADDR_SIZE;
+
+	return ioread64(hw_info->ap_pdn_base + offset);
+}
+
+void t7xx_cldma_hw_set_start_addr(struct t7xx_cldma_hw *hw_info, unsigned int qno, u64 address,
+				  enum mtk_txrx tx_rx)
+{
+	u32 offset = qno * ADDR_SIZE;
+	void __iomem *reg;
+
+	reg = tx_rx == MTK_RX ? hw_info->ap_ao_base + REG_CLDMA_DL_START_ADDRL_0 :
+				hw_info->ap_pdn_base + REG_CLDMA_UL_START_ADDRL_0;
+	iowrite64(address, reg + offset);
+}
+
+void t7xx_cldma_hw_resume_queue(struct t7xx_cldma_hw *hw_info, unsigned int qno,
+				enum mtk_txrx tx_rx)
+{
+	void __iomem *base = hw_info->ap_pdn_base;
+
+	if (tx_rx == MTK_RX)
+		iowrite32(BIT(qno), base + REG_CLDMA_DL_RESUME_CMD);
+	else
+		iowrite32(BIT(qno), base + REG_CLDMA_UL_RESUME_CMD);
+}
+
+unsigned int t7xx_cldma_hw_queue_status(struct t7xx_cldma_hw *hw_info, unsigned int qno,
+					enum mtk_txrx tx_rx)
+{
+	void __iomem *reg;
+	u32 mask, val;
+
+	mask = qno == CLDMA_ALL_Q ? CLDMA_ALL_Q : BIT(qno);
+	reg = tx_rx == MTK_RX ? hw_info->ap_ao_base + REG_CLDMA_DL_STATUS :
+				hw_info->ap_pdn_base + REG_CLDMA_UL_STATUS;
+	val = ioread32(reg);
+
+	return val & mask;
+}
+
+void t7xx_cldma_hw_tx_done(struct t7xx_cldma_hw *hw_info, unsigned int bitmask)
+{
+	unsigned int ch_id;
+
+	ch_id = ioread32(hw_info->ap_pdn_base + REG_CLDMA_L2TISAR0);
+	ch_id &= bitmask;
+	/* Clear the ch IDs in the TX interrupt status register */
+	iowrite32(ch_id, hw_info->ap_pdn_base + REG_CLDMA_L2TISAR0);
+	ioread32(hw_info->ap_pdn_base + REG_CLDMA_L2TISAR0);
+}
+
+void t7xx_cldma_hw_rx_done(struct t7xx_cldma_hw *hw_info, unsigned int bitmask)
+{
+	unsigned int ch_id;
+
+	ch_id = ioread32(hw_info->ap_pdn_base + REG_CLDMA_L2RISAR0);
+	ch_id &= bitmask;
+	/* Clear the ch IDs in the RX interrupt status register */
+	iowrite32(ch_id, hw_info->ap_pdn_base + REG_CLDMA_L2RISAR0);
+	ioread32(hw_info->ap_pdn_base + REG_CLDMA_L2RISAR0);
+}
+
+unsigned int t7xx_cldma_hw_int_status(struct t7xx_cldma_hw *hw_info, unsigned int bitmask,
+				      enum mtk_txrx tx_rx)
+{
+	void __iomem *reg;
+	u32 val;
+
+	reg = tx_rx == MTK_RX ? hw_info->ap_pdn_base + REG_CLDMA_L2RISAR0 :
+				hw_info->ap_pdn_base + REG_CLDMA_L2TISAR0;
+	val = ioread32(reg);
+	return val & bitmask;
+}
+
+void t7xx_cldma_hw_irq_dis_txrx(struct t7xx_cldma_hw *hw_info, unsigned int qno,
+				enum mtk_txrx tx_rx)
+{
+	void __iomem *reg;
+	u32 val;
+
+	reg = tx_rx == MTK_RX ? hw_info->ap_ao_base + REG_CLDMA_L2RIMSR0 :
+				hw_info->ap_pdn_base + REG_CLDMA_L2TIMSR0;
+	val = qno == CLDMA_ALL_Q ? CLDMA_ALL_Q : BIT(qno);
+	iowrite32(val, reg);
+}
+
+void t7xx_cldma_hw_irq_dis_eq(struct t7xx_cldma_hw *hw_info, unsigned int qno, enum mtk_txrx tx_rx)
+{
+	void __iomem *reg;
+	u32 val;
+
+	reg = tx_rx == MTK_RX ? hw_info->ap_ao_base + REG_CLDMA_L2RIMSR0 :
+				hw_info->ap_pdn_base + REG_CLDMA_L2TIMSR0;
+	val = qno == CLDMA_ALL_Q ? CLDMA_ALL_Q : BIT(qno);
+	iowrite32(val << EQ_STA_BIT_OFFSET, reg);
+}
+
+void t7xx_cldma_hw_irq_en_txrx(struct t7xx_cldma_hw *hw_info, unsigned int qno,
+			       enum mtk_txrx tx_rx)
+{
+	void __iomem *reg;
+	u32 val;
+
+	reg = tx_rx == MTK_RX ? hw_info->ap_ao_base + REG_CLDMA_L2RIMCR0 :
+				hw_info->ap_pdn_base + REG_CLDMA_L2TIMCR0;
+	val = qno == CLDMA_ALL_Q ? CLDMA_ALL_Q : BIT(qno);
+	iowrite32(val, reg);
+}
+
+void t7xx_cldma_hw_irq_en_eq(struct t7xx_cldma_hw *hw_info, unsigned int qno, enum mtk_txrx tx_rx)
+{
+	void __iomem *reg;
+	u32 val;
+
+	reg = tx_rx == MTK_RX ? hw_info->ap_ao_base + REG_CLDMA_L2RIMCR0 :
+				hw_info->ap_pdn_base + REG_CLDMA_L2TIMCR0;
+	val = qno == CLDMA_ALL_Q ? CLDMA_ALL_Q : BIT(qno);
+	iowrite32(val << EQ_STA_BIT_OFFSET, reg);
+}
+
+/**
+ * t7xx_cldma_hw_init() - Initialize CLDMA HW.
+ * @hw_info: Pointer to struct t7xx_cldma_hw.
+ *
+ * Write uplink and downlink configuration to CLDMA HW.
+ */
+void t7xx_cldma_hw_init(struct t7xx_cldma_hw *hw_info)
+{
+	u32 ul_cfg, dl_cfg;
+
+	ul_cfg = ioread32(hw_info->ap_pdn_base + REG_CLDMA_UL_CFG);
+	dl_cfg = ioread32(hw_info->ap_ao_base + REG_CLDMA_DL_CFG);
+	/* Configure the DRAM address mode */
+	ul_cfg &= ~UL_CFG_BIT_MODE_MASK;
+	dl_cfg &= ~DL_CFG_BIT_MODE_MASK;
+
+	if (hw_info->hw_mode == MODE_BIT_64) {
+		ul_cfg |= UL_CFG_BIT_MODE_64;
+		dl_cfg |= DL_CFG_BIT_MODE_64;
+	} else if (hw_info->hw_mode == MODE_BIT_40) {
+		ul_cfg |= UL_CFG_BIT_MODE_40;
+		dl_cfg |= DL_CFG_BIT_MODE_40;
+	} else if (hw_info->hw_mode == MODE_BIT_36) {
+		ul_cfg |= UL_CFG_BIT_MODE_36;
+		dl_cfg |= DL_CFG_BIT_MODE_36;
+	}
+
+	iowrite32(ul_cfg, hw_info->ap_pdn_base + REG_CLDMA_UL_CFG);
+	dl_cfg |= DL_CFG_UP_HW_LAST;
+	iowrite32(dl_cfg, hw_info->ap_ao_base + REG_CLDMA_DL_CFG);
+	iowrite32(0, hw_info->ap_ao_base + REG_CLDMA_INT_MASK);
+	iowrite32(BUSY_MASK_MD, hw_info->ap_ao_base + REG_CLDMA_BUSY_MASK);
+	iowrite32(UL_MEM_CHECK_DIS, hw_info->ap_pdn_base + REG_CLDMA_UL_MEM);
+	iowrite32(DL_MEM_CHECK_DIS, hw_info->ap_pdn_base + REG_CLDMA_DL_MEM);
+}
+
+void t7xx_cldma_hw_stop_all_qs(struct t7xx_cldma_hw *hw_info, enum mtk_txrx tx_rx)
+{
+	void __iomem *reg;
+
+	reg = tx_rx == MTK_RX ? hw_info->ap_pdn_base + REG_CLDMA_DL_STOP_CMD :
+				hw_info->ap_pdn_base + REG_CLDMA_UL_STOP_CMD;
+	iowrite32(CLDMA_ALL_Q, reg);
+}
+
+void t7xx_cldma_hw_stop(struct t7xx_cldma_hw *hw_info, enum mtk_txrx tx_rx)
+{
+	void __iomem *reg;
+
+	reg = tx_rx == MTK_RX ? hw_info->ap_ao_base + REG_CLDMA_L2RIMSR0 :
+				hw_info->ap_pdn_base + REG_CLDMA_L2TIMSR0;
+	iowrite32(TXRX_STATUS_BITMASK, reg);
+	iowrite32(EMPTY_STATUS_BITMASK, reg);
+}

drivers/net/wwan/t7xx/t7xx_cldma.h

···
+/* SPDX-License-Identifier: GPL-2.0-only
+ *
+ * Copyright (c) 2021, MediaTek Inc.
+ * Copyright (c) 2021-2022, Intel Corporation.
+ *
+ * Authors:
+ *  Haijun Liu <[e-mail]>
+ *  Moises Veleta <[e-mail]>
+ *  Ricardo Martinez <[e-mail]>
+ *
+ * Contributors:
+ *  Amir Hanania <[e-mail]>
+ *  Andy Shevchenko <[e-mail]>
+ *  Sreehari Kancharla <[e-mail]>
+ */
+
+#ifndef __T7XX_CLDMA_H__
+#define __T7XX_CLDMA_H__
+
+#include <linux/bits.h>
+#include <linux/types.h>
+
+#define CLDMA_TXQ_NUM			8
+#define CLDMA_RXQ_NUM			8
+#define CLDMA_ALL_Q			GENMASK(7, 0)
+
+/* Interrupt status bits */
+#define EMPTY_STATUS_BITMASK		GENMASK(15, 8)
+#define TXRX_STATUS_BITMASK		GENMASK(7, 0)
+#define EQ_STA_BIT_OFFSET		8
+#define L2_INT_BIT_COUNT		16
+#define EQ_STA_BIT(index)		(BIT((index) + EQ_STA_BIT_OFFSET) & EMPTY_STATUS_BITMASK)
+
+#define TQ_ERR_INT_BITMASK		GENMASK(23, 16)
+#define TQ_ACTIVE_START_ERR_INT_BITMASK	GENMASK(31, 24)
+
+#define RQ_ERR_INT_BITMASK		GENMASK(23, 16)
+#define RQ_ACTIVE_START_ERR_INT_BITMASK	GENMASK(31, 24)
+
+#define CLDMA0_AO_BASE			0x10049000
+#define CLDMA0_PD_BASE			0x1021d000
+#define CLDMA1_AO_BASE			0x1004b000
+#define CLDMA1_PD_BASE			0x1021f000
+
+#define CLDMA_R_AO_BASE			0x10023000
+#define CLDMA_R_PD_BASE			0x1023d000
+
+/* CLDMA TX */
+#define REG_CLDMA_UL_START_ADDRL_0	0x0004
+#define REG_CLDMA_UL_START_ADDRH_0	0x0008
+#define REG_CLDMA_UL_CURRENT_ADDRL_0	0x0044
+#define REG_CLDMA_UL_CURRENT_ADDRH_0	0x0048
+#define REG_CLDMA_UL_STATUS		0x0084
+#define REG_CLDMA_UL_START_CMD		0x0088
+#define REG_CLDMA_UL_RESUME_CMD		0x008c
+#define REG_CLDMA_UL_STOP_CMD		0x0090
+#define REG_CLDMA_UL_ERROR		0x0094
+#define REG_CLDMA_UL_CFG		0x0098
+#define UL_CFG_BIT_MODE_36		BIT(5)
+#define UL_CFG_BIT_MODE_40		BIT(6)
+#define UL_CFG_BIT_MODE_64		BIT(7)
+#define UL_CFG_BIT_MODE_MASK		GENMASK(7, 5)
+
+#define REG_CLDMA_UL_MEM		0x009c
+#define UL_MEM_CHECK_DIS		BIT(0)
+
+/* CLDMA RX */
+#define REG_CLDMA_DL_START_CMD		0x05bc
+#define REG_CLDMA_DL_RESUME_CMD		0x05c0
+#define REG_CLDMA_DL_STOP_CMD		0x05c4
+#define REG_CLDMA_DL_MEM		0x0508
+#define DL_MEM_CHECK_DIS		BIT(0)
+
+#define REG_CLDMA_DL_CFG		0x0404
+#define DL_CFG_UP_HW_LAST		BIT(2)
+#define DL_CFG_BIT_MODE_36		BIT(10)
+#define DL_CFG_BIT_MODE_40		BIT(11)
+#define DL_CFG_BIT_MODE_64		BIT(12)
+#define DL_CFG_BIT_MODE_MASK		GENMASK(12, 10)
+
+#define REG_CLDMA_DL_START_ADDRL_0	0x0478
+#define REG_CLDMA_DL_START_ADDRH_0	0x047c
+#define REG_CLDMA_DL_CURRENT_ADDRL_0	0x04b8
+#define REG_CLDMA_DL_CURRENT_ADDRH_0	0x04bc
+#define REG_CLDMA_DL_STATUS		0x04f8
+
+/* CLDMA MISC */
+#define REG_CLDMA_L2TISAR0		0x0810
+#define REG_CLDMA_L2TISAR1		0x0814
+#define REG_CLDMA_L2TIMR0		0x0818
+#define REG_CLDMA_L2TIMR1		0x081c
+#define REG_CLDMA_L2TIMCR0		0x0820
+#define REG_CLDMA_L2TIMCR1		0x0824
+#define REG_CLDMA_L2TIMSR0		0x0828
+#define REG_CLDMA_L2TIMSR1		0x082c
+#define REG_CLDMA_L3TISAR0		0x0830
+#define REG_CLDMA_L3TISAR1		0x0834
+#define REG_CLDMA_L2RISAR0		0x0850
+#define REG_CLDMA_L2RISAR1		0x0854
+#define REG_CLDMA_L3RISAR0		0x0870
+#define REG_CLDMA_L3RISAR1		0x0874
+#define REG_CLDMA_IP_BUSY		0x08b4
+#define IP_BUSY_WAKEUP			BIT(0)
+#define CLDMA_L2TISAR0_ALL_INT_MASK	GENMASK(15, 0)
+#define CLDMA_L2RISAR0_ALL_INT_MASK	GENMASK(15, 0)
+
+/* CLDMA MISC */
+#define REG_CLDMA_L2RIMR0		0x0858
+#define REG_CLDMA_L2RIMR1		0x085c
+#define REG_CLDMA_L2RIMCR0		0x0860
+#define REG_CLDMA_L2RIMCR1		0x0864
+#define REG_CLDMA_L2RIMSR0		0x0868
+#define REG_CLDMA_L2RIMSR1		0x086c
+#define REG_CLDMA_BUSY_MASK		0x0954
+#define BUSY_MASK_PCIE			BIT(0)
+#define BUSY_MASK_AP			BIT(1)
+#define BUSY_MASK_MD			BIT(2)
+
+#define REG_CLDMA_INT_MASK		0x0960
+
+/* CLDMA RESET */
+#define REG_INFRA_RST4_SET		0x0730
+#define RST4_CLDMA1_SW_RST_SET		BIT(20)
+
+#define REG_INFRA_RST4_CLR		0x0734
+#define RST4_CLDMA1_SW_RST_CLR		BIT(20)
+
+#define REG_INFRA_RST2_SET		0x0140
+#define RST2_PMIC_SW_RST_SET		BIT(18)
+
+#define REG_INFRA_RST2_CLR		0x0144
+#define RST2_PMIC_SW_RST_CLR		BIT(18)
+
+enum mtk_txrx {
+	MTK_TX,
+	MTK_RX,
+};
+
+enum t7xx_hw_mode {
+	MODE_BIT_32,
+	MODE_BIT_36,
+	MODE_BIT_40,
+	MODE_BIT_64,
+};
+
+struct t7xx_cldma_hw {
+	enum t7xx_hw_mode		hw_mode;
+	void __iomem			*ap_ao_base;
+	void __iomem			*ap_pdn_base;
+	u32				phy_interrupt_id;
+};
+
+void t7xx_cldma_hw_irq_dis_txrx(struct t7xx_cldma_hw *hw_info, unsigned int qno,
+				enum mtk_txrx tx_rx);
+void t7xx_cldma_hw_irq_dis_eq(struct t7xx_cldma_hw *hw_info, unsigned int qno,
+			      enum mtk_txrx tx_rx);
+void t7xx_cldma_hw_irq_en_txrx(struct t7xx_cldma_hw *hw_info, unsigned int qno,
+			       enum mtk_txrx tx_rx);
+void t7xx_cldma_hw_irq_en_eq(struct t7xx_cldma_hw *hw_info, unsigned int qno, enum mtk_txrx tx_rx);
+unsigned int t7xx_cldma_hw_queue_status(struct t7xx_cldma_hw *hw_info, unsigned int qno,
+					enum mtk_txrx tx_rx);
+void t7xx_cldma_hw_init(struct t7xx_cldma_hw *hw_info);
+void t7xx_cldma_hw_resume_queue(struct t7xx_cldma_hw *hw_info, unsigned int qno,
+				enum mtk_txrx tx_rx);
+void t7xx_cldma_hw_start(struct t7xx_cldma_hw *hw_info);
+void t7xx_cldma_hw_start_queue(struct t7xx_cldma_hw *hw_info, unsigned int qno,
+			       enum mtk_txrx tx_rx);
+void t7xx_cldma_hw_tx_done(struct t7xx_cldma_hw *hw_info, unsigned int bitmask);
+void t7xx_cldma_hw_rx_done(struct t7xx_cldma_hw *hw_info, unsigned int bitmask);
+void t7xx_cldma_hw_stop_all_qs(struct t7xx_cldma_hw *hw_info, enum mtk_txrx tx_rx);
+void t7xx_cldma_hw_set_start_addr(struct t7xx_cldma_hw *hw_info,
+				  unsigned int qno, u64 address, enum mtk_txrx tx_rx);
+void t7xx_cldma_hw_reset(void __iomem *ao_base);
+void t7xx_cldma_hw_stop(struct t7xx_cldma_hw *hw_info, enum mtk_txrx tx_rx);
+unsigned int t7xx_cldma_hw_int_status(struct t7xx_cldma_hw *hw_info, unsigned int bitmask,
+				      enum mtk_txrx tx_rx);
+void t7xx_cldma_hw_restore(struct t7xx_cldma_hw *hw_info);
+void t7xx_cldma_clear_ip_busy(struct t7xx_cldma_hw *hw_info);
+bool t7xx_cldma_tx_addr_is_set(struct t7xx_cldma_hw *hw_info, unsigned int qno);
+#endif

drivers/net/wwan/t7xx/t7xx_hif_cldma.c

···
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2021, MediaTek Inc.
+ * Copyright (c) 2021-2022, Intel Corporation.
+ *
+ * Authors:
+ *  Amir Hanania <[e-mail]>
+ *  Haijun Liu <[e-mail]>
+ *  Moises Veleta <[e-mail]>
+ *  Ricardo Martinez <[e-mail]>
+ *  Sreehari Kancharla <[e-mail]>
+ *
+ * Contributors:
+ *  Andy Shevchenko <[e-mail]>
+ *  Chiranjeevi Rapolu <[e-mail]>
+ *  Eliot Lee <[e-mail]>
+ */
+
+#include <linux/bits.h>
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dmapool.h>
+#include <linux/dma-mapping.h>
+#include <linux/dma-direction.h>
+#include <linux/gfp.h>
+#include <linux/io.h>
+#include <linux/io-64-nonatomic-lo-hi.h>
+#include <linux/iopoll.h>
+#include <linux/irqreturn.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <linux/list.h>
+#include <linux/netdevice.h>
+#include <linux/pci.h>
+#include <linux/sched.h>
+#include <linux/skbuff.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+#include <linux/wait.h>
+#include <linux/workqueue.h>
+
+#include "t7xx_cldma.h"
+#include "t7xx_hif_cldma.h"
+#include "t7xx_mhccif.h"
+#include "t7xx_pci.h"
+#include "t7xx_pcie_mac.h"
+#include "t7xx_reg.h"
+#include "t7xx_state_monitor.h"
+
+#define MAX_TX_BUDGET			16
+#define MAX_RX_BUDGET			16
+
+#define CHECK_Q_STOP_TIMEOUT_US		1000000
+#define CHECK_Q_STOP_STEP_US		10000
+
+#define CLDMA_JUMBO_BUFF_SZ		64528	/* 63kB + CCCI header */
+
+static void md_cd_queue_struct_reset(struct cldma_queue *queue, struct cldma_ctrl *md_ctrl,
+				     enum mtk_txrx tx_rx, unsigned int index)
+{
+	queue->dir = tx_rx;
+	queue->index = index;
+	queue->md_ctrl = md_ctrl;
+	queue->tr_ring = NULL;
+	queue->tr_done = NULL;
+	queue->tx_next = NULL;
+}
+
+static void md_cd_queue_struct_init(struct cldma_queue *queue, struct cldma_ctrl *md_ctrl,
+				    enum mtk_txrx tx_rx, unsigned int index)
+{
+	md_cd_queue_struct_reset(queue, md_ctrl, tx_rx, index);
+	init_waitqueue_head(&queue->req_wq);
+	spin_lock_init(&queue->ring_lock);
+}
+
+static void t7xx_cldma_gpd_set_data_ptr(struct cldma_gpd *gpd, dma_addr_t data_ptr)
+{
+	gpd->data_buff_bd_ptr_h = cpu_to_le32(upper_32_bits(data_ptr));
+	gpd->data_buff_bd_ptr_l = cpu_to_le32(lower_32_bits(data_ptr));
+}
+
+static void t7xx_cldma_gpd_set_next_ptr(struct cldma_gpd *gpd, dma_addr_t next_ptr)
+{
+	gpd->next_gpd_ptr_h = cpu_to_le32(upper_32_bits(next_ptr));
+	gpd->next_gpd_ptr_l = cpu_to_le32(lower_32_bits(next_ptr));
+}
+
+static int t7xx_cldma_alloc_and_map_skb(struct cldma_ctrl *md_ctrl, struct cldma_request *req,
+					size_t size)
+{
+	req->skb = __dev_alloc_skb(size, GFP_KERNEL);
+	if (!req->skb)
+		return -ENOMEM;
+
+	req->mapped_buff = dma_map_single(md_ctrl->dev, req->skb->data,
+					  skb_data_area_size(req->skb), DMA_FROM_DEVICE);
+	if (dma_mapping_error(md_ctrl->dev, req->mapped_buff)) {
+		dev_kfree_skb_any(req->skb);
+		req->skb = NULL;
+		req->mapped_buff = 0;
+		dev_err(md_ctrl->dev, "DMA mapping failed\n");
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static int t7xx_cldma_gpd_rx_from_q(struct cldma_queue *queue, int budget, bool *over_budget)
+{
+	struct cldma_ctrl *md_ctrl = queue->md_ctrl;
+	unsigned int hwo_polling_count = 0;
+	struct t7xx_cldma_hw *hw_info;
+	bool rx_not_done = true;
+	unsigned long flags;
+	int count = 0;
+
+	hw_info = &md_ctrl->hw_info;
+
+	do {
+		struct cldma_request *req;
+		struct cldma_gpd *gpd;
+		struct sk_buff *skb;
+		int ret;
+
+		req = queue->tr_done;
+		if (!req)
+			return -ENODATA;
+
+		gpd = req->gpd;
+		if ((gpd->flags & GPD_FLAGS_HWO) || !req->skb) {
+			dma_addr_t gpd_addr;
+
+			if (!pci_device_is_present(to_pci_dev(md_ctrl->dev))) {
+				dev_err(md_ctrl->dev, "PCIe Link disconnected\n");
+				return -ENODEV;
+			}
+
+			gpd_addr = ioread64(hw_info->ap_pdn_base + REG_CLDMA_DL_CURRENT_ADDRL_0 +
+					    queue->index * sizeof(u64));
+			if (req->gpd_addr == gpd_addr || hwo_polling_count++ >= 100)
+				return 0;
+
+			udelay(1);
+			continue;
+		}
+
+		hwo_polling_count = 0;
+		skb = req->skb;
+
+		if (req->mapped_buff) {
+			dma_unmap_single(md_ctrl->dev, req->mapped_buff,
+					 skb_data_area_size(skb), DMA_FROM_DEVICE);
+			req->mapped_buff = 0;
+		}
+
+		skb->len = 0;
+		skb_reset_tail_pointer(skb);
+		skb_put(skb, le16_to_cpu(gpd->data_buff_len));
+
+		ret = md_ctrl->recv_skb(queue, skb);
+		/* Break processing, will try again later */
+		if (ret < 0)
+			return ret;
+
+		req->skb = NULL;
+		t7xx_cldma_gpd_set_data_ptr(gpd, 0);
+
+		spin_lock_irqsave(&queue->ring_lock, flags);
+		queue->tr_done = list_next_entry_circular(req, &queue->tr_ring->gpd_ring, entry);
+		spin_unlock_irqrestore(&queue->ring_lock, flags);
+		req = queue->rx_refill;
+
+		ret = t7xx_cldma_alloc_and_map_skb(md_ctrl, req, queue->tr_ring->pkt_size);
+		if (ret)
+			return ret;
+
+		gpd = req->gpd;
+		t7xx_cldma_gpd_set_data_ptr(gpd, req->mapped_buff);
+		gpd->data_buff_len = 0;
+		gpd->flags = GPD_FLAGS_IOC | GPD_FLAGS_HWO;
+
+		spin_lock_irqsave(&queue->ring_lock, flags);
+		queue->rx_refill = list_next_entry_circular(req, &queue->tr_ring->gpd_ring, entry);
+		spin_unlock_irqrestore(&queue->ring_lock, flags);
+
+		rx_not_done = ++count < budget || !need_resched();
+	} while (rx_not_done);
+
+	*over_budget = true;
+	return 0;
+}
+
+static int t7xx_cldma_gpd_rx_collect(struct cldma_queue *queue, int budget)
+{
+	struct cldma_ctrl *md_ctrl = queue->md_ctrl;
+	struct t7xx_cldma_hw *hw_info;
+	unsigned int pending_rx_int;
+	bool over_budget = false;
+	unsigned long flags;
+	int ret;
+
+	hw_info = &md_ctrl->hw_info;
+
+	do {
+		ret = t7xx_cldma_gpd_rx_from_q(queue, budget, &over_budget);
+		if (ret == -ENODATA)
+			return 0;
+		else if (ret)
+			return ret;
+
+		pending_rx_int = 0;
+
+		spin_lock_irqsave(&md_ctrl->cldma_lock, flags);
+		if (md_ctrl->rxq_active & BIT(queue->index)) {
+			if (!t7xx_cldma_hw_queue_status(hw_info, queue->index, MTK_RX))
+				t7xx_cldma_hw_resume_queue(hw_info, queue->index, MTK_RX);
+
+			pending_rx_int = t7xx_cldma_hw_int_status(hw_info, BIT(queue->index),
+								  MTK_RX);
+			if (pending_rx_int) {
+				t7xx_cldma_hw_rx_done(hw_info, pending_rx_int);
+
+				if (over_budget) {
+					spin_unlock_irqrestore(&md_ctrl->cldma_lock, flags);
+					return -EAGAIN;
+				}
+			}
+		}
+		spin_unlock_irqrestore(&md_ctrl->cldma_lock, flags);
+	} while (pending_rx_int);
+
+	return 0;
+}
+
+static void t7xx_cldma_rx_done(struct work_struct *work)
+{
+	struct cldma_queue *queue = container_of(work, struct cldma_queue, cldma_work);
+	struct cldma_ctrl *md_ctrl = queue->md_ctrl;
+	int value;
+
+	value = t7xx_cldma_gpd_rx_collect(queue, queue->budget);
+	if (value && md_ctrl->rxq_active & BIT(queue->index)) {
+		queue_work(queue->worker, &queue->cldma_work);
+		return;
+	}
+
+	t7xx_cldma_clear_ip_busy(&md_ctrl->hw_info);
+	t7xx_cldma_hw_irq_en_txrx(&md_ctrl->hw_info, queue->index, MTK_RX);
+	t7xx_cldma_hw_irq_en_eq(&md_ctrl->hw_info, queue->index, MTK_RX);
+}
+
+static int t7xx_cldma_gpd_tx_collect(struct cldma_queue *queue)
+{
+	struct cldma_ctrl *md_ctrl = queue->md_ctrl;
+	unsigned int dma_len, count = 0;
+	struct cldma_request *req;
+	struct cldma_gpd *gpd;
+	unsigned long flags;
+	dma_addr_t dma_free;
+	struct sk_buff *skb;
+
+	while (!kthread_should_stop()) {
+		spin_lock_irqsave(&queue->ring_lock, flags);
+		req = queue->tr_done;
+		if (!req) {
+			spin_unlock_irqrestore(&queue->ring_lock, flags);
+			break;
+		}
+		gpd = req->gpd;
+		if ((gpd->flags & GPD_FLAGS_HWO) || !req->skb) {
+			spin_unlock_irqrestore(&queue->ring_lock, flags);
+			break;
+		}
+		queue->budget++;
+		dma_free = req->mapped_buff;
+		dma_len = le16_to_cpu(gpd->data_buff_len);
+		skb = req->skb;
+		req->skb = NULL;
+		queue->tr_done = list_next_entry_circular(req, &queue->tr_ring->gpd_ring, entry);
+		spin_unlock_irqrestore(&queue->ring_lock, flags);
+
+		count++;
+		dma_unmap_single(md_ctrl->dev, dma_free, dma_len, DMA_TO_DEVICE);
+		dev_kfree_skb_any(skb);
+	}
+
+	if (count)
+		wake_up_nr(&queue->req_wq, count);
+
+	return count;
+}
+
+static void t7xx_cldma_txq_empty_hndl(struct cldma_queue *queue)
+{
+	struct cldma_ctrl *md_ctrl = queue->md_ctrl;
+	struct cldma_request *req;
+	dma_addr_t ul_curr_addr;
+	unsigned long flags;
+	bool pending_gpd;
+
+	if (!(md_ctrl->txq_active & BIT(queue->index)))
+		return;
+
+	spin_lock_irqsave(&queue->ring_lock, flags);
+	req = list_prev_entry_circular(queue->tx_next, &queue->tr_ring->gpd_ring, entry);
+	spin_unlock_irqrestore(&queue->ring_lock, flags);
+
+	pending_gpd = (req->gpd->flags & GPD_FLAGS_HWO) && req->skb;
+
+	spin_lock_irqsave(&md_ctrl->cldma_lock, flags);
+	if (pending_gpd) {
+		struct t7xx_cldma_hw *hw_info = &md_ctrl->hw_info;
+
+		/* Check current processing TGPD, 64-bit address is in a table by Q index */
+		ul_curr_addr = ioread64(hw_info->ap_pdn_base + REG_CLDMA_UL_CURRENT_ADDRL_0 +
+					queue->index * sizeof(u64));
+		if (req->gpd_addr != ul_curr_addr) {
+			spin_unlock_irqrestore(&md_ctrl->cldma_lock, flags);
+			dev_err(md_ctrl->dev, "CLDMA%d queue %d is not empty\n",
+				md_ctrl->hif_id, queue->index);
+			return;
+		}
+
+		t7xx_cldma_hw_resume_queue(hw_info, queue->index, MTK_TX);
+	}
+	spin_unlock_irqrestore(&md_ctrl->cldma_lock, flags);
+}
+
+static void t7xx_cldma_tx_done(struct work_struct *work)
+{
+	struct cldma_queue *queue = container_of(work, struct cldma_queue, cldma_work);
+	struct cldma_ctrl *md_ctrl = queue->md_ctrl;
+	struct t7xx_cldma_hw *hw_info;
+	unsigned int l2_tx_int;
+	unsigned long flags;
+
+	hw_info = &md_ctrl->hw_info;
+	t7xx_cldma_gpd_tx_collect(queue);
+	l2_tx_int = t7xx_cldma_hw_int_status(hw_info, BIT(queue->index) | EQ_STA_BIT(queue->index),
+					     MTK_TX);
+	if (l2_tx_int & EQ_STA_BIT(queue->index)) {
+		t7xx_cldma_hw_tx_done(hw_info, EQ_STA_BIT(queue->index));
+		t7xx_cldma_txq_empty_hndl(queue);
+	}
+
+	if (l2_tx_int & BIT(queue->index)) {
+		t7xx_cldma_hw_tx_done(hw_info, BIT(queue->index));
+		queue_work(queue->worker, &queue->cldma_work);
+		return;
+	}
+
+	spin_lock_irqsave(&md_ctrl->cldma_lock, flags);
+	if (md_ctrl->txq_active & BIT(queue->index)) {
+		t7xx_cldma_clear_ip_busy(hw_info);
+		t7xx_cldma_hw_irq_en_eq(hw_info, queue->index, MTK_TX);
+		t7xx_cldma_hw_irq_en_txrx(hw_info, queue->index, MTK_TX);
+	}
+	spin_unlock_irqrestore(&md_ctrl->cldma_lock, flags);
+}
+
+static void t7xx_cldma_ring_free(struct cldma_ctrl *md_ctrl,
+				 struct cldma_ring *ring, enum dma_data_direction tx_rx)
+{
+	struct cldma_request *req_cur, *req_next;
+
+	list_for_each_entry_safe(req_cur, req_next, &ring->gpd_ring, entry) {
+		if (req_cur->mapped_buff && req_cur->skb) {
+			dma_unmap_single(md_ctrl->dev, req_cur->mapped_buff,
+					 skb_data_area_size(req_cur->skb), tx_rx);
+			req_cur->mapped_buff = 0;
+		}
+
+		dev_kfree_skb_any(req_cur->skb);
+
+		if (req_cur->gpd)
+			dma_pool_free(md_ctrl->gpd_dmapool, req_cur->gpd, req_cur->gpd_addr);
+
+		list_del(&req_cur->entry);
+		kfree(req_cur);
+	}
+}
+
+static struct cldma_request *t7xx_alloc_rx_request(struct cldma_ctrl *md_ctrl, size_t pkt_size)
+{
+	struct cldma_request *req;
+	int val;
+
+	req = kzalloc(sizeof(*req), GFP_KERNEL);
+	if (!req)
+		return NULL;
+
+	req->gpd = dma_pool_zalloc(md_ctrl->gpd_dmapool, GFP_KERNEL, &req->gpd_addr);
+	if (!req->gpd)
+		goto err_free_req;
+
+	val = t7xx_cldma_alloc_and_map_skb(md_ctrl, req, pkt_size);
+	if (val)
+		goto err_free_pool;
+
+	return req;
+
+err_free_pool:
+	dma_pool_free(md_ctrl->gpd_dmapool, req->gpd, req->gpd_addr);
+
+err_free_req:
+	kfree(req);
+
+	return NULL;
+}
+
+static int t7xx_cldma_rx_ring_init(struct cldma_ctrl *md_ctrl, struct cldma_ring *ring)
+{
+	struct cldma_request *req;
+	struct cldma_gpd *gpd;
+	int i;
+
+	INIT_LIST_HEAD(&ring->gpd_ring);
+	ring->length = MAX_RX_BUDGET;
+
+	for (i = 0; i < ring->length; i++) {
+		req = t7xx_alloc_rx_request(md_ctrl, ring->pkt_size);
+		if (!req) {
+			t7xx_cldma_ring_free(md_ctrl, ring, DMA_FROM_DEVICE);
+			return -ENOMEM;
+		}
+
+		gpd = req->gpd;
+		t7xx_cldma_gpd_set_data_ptr(gpd, req->mapped_buff);
+		gpd->rx_data_allow_len = cpu_to_le16(ring->pkt_size);
+		gpd->flags = GPD_FLAGS_IOC | GPD_FLAGS_HWO;
+		INIT_LIST_HEAD(&req->entry);
+		list_add_tail(&req->entry, &ring->gpd_ring);
+	}
+
+	/* Link previous GPD to next GPD, circular */
+	list_for_each_entry(req, &ring->gpd_ring, entry) {
+		t7xx_cldma_gpd_set_next_ptr(gpd, req->gpd_addr);
+		gpd = req->gpd;
+	}
+
+	return 0;
+}
+
+static struct cldma_request *t7xx_alloc_tx_request(struct cldma_ctrl *md_ctrl)
+{
+	struct cldma_request *req;
+
+	req = kzalloc(sizeof(*req), GFP_KERNEL);
+	if (!req)
+		return NULL;
+
+	req->gpd = dma_pool_zalloc(md_ctrl->gpd_dmapool, GFP_KERNEL, &req->gpd_addr);
+	if (!req->gpd) {
+		kfree(req);
+		return NULL;
+	}
+
+	return req;
+}
+
+static int t7xx_cldma_tx_ring_init(struct cldma_ctrl *md_ctrl, struct cldma_ring *ring)
+{
+	struct cldma_request *req;
+	struct cldma_gpd *gpd;
+	int i;
+
+	INIT_LIST_HEAD(&ring->gpd_ring);
+	ring->length = MAX_TX_BUDGET;
+
+	for (i = 0; i < ring->length; i++) {
+		req = t7xx_alloc_tx_request(md_ctrl);
+		if (!req) {
+			t7xx_cldma_ring_free(md_ctrl, ring, DMA_TO_DEVICE);
+			return -ENOMEM;
+		}
+
+		gpd = req->gpd;
+		gpd->flags = GPD_FLAGS_IOC;
+		INIT_LIST_HEAD(&req->entry);
+		list_add_tail(&req->entry, &ring->gpd_ring);
+	}
+
+	/* Link previous GPD to next GPD, circular */
+	list_for_each_entry(req, &ring->gpd_ring, entry) {
+		t7xx_cldma_gpd_set_next_ptr(gpd, req->gpd_addr);
+		gpd = req->gpd;
+	}
+
+	return 0;
+}
+
+/**
+ * t7xx_cldma_q_reset() - Reset CLDMA request pointers to their initial values.
+ * @queue: Pointer to the queue structure.
+ *
+ * Called with ring_lock (unless called during initialization phase)
+ */
+static void t7xx_cldma_q_reset(struct cldma_queue *queue)
+{
+	struct cldma_request *req;
+
+	req = list_first_entry(&queue->tr_ring->gpd_ring, struct cldma_request, entry);
+	queue->tr_done = req;
+	queue->budget = queue->tr_ring->length;
+
+	if (queue->dir == MTK_TX)
+		queue->tx_next = req;
+	else
+		queue->rx_refill = req;
+}
+
+static void t7xx_cldma_rxq_init(struct cldma_queue *queue)
+{
+	struct cldma_ctrl *md_ctrl = queue->md_ctrl;
+
+	queue->dir = MTK_RX;
+	queue->tr_ring = &md_ctrl->rx_ring[queue->index];
+	t7xx_cldma_q_reset(queue);
+}
+
+static void t7xx_cldma_txq_init(struct cldma_queue *queue)
+{
+	struct cldma_ctrl *md_ctrl = queue->md_ctrl;
+
+	queue->dir = MTK_TX;
+	queue->tr_ring = &md_ctrl->tx_ring[queue->index];
+	t7xx_cldma_q_reset(queue);
+}
+
+static void t7xx_cldma_enable_irq(struct cldma_ctrl *md_ctrl)
+{
+	t7xx_pcie_mac_set_int(md_ctrl->t7xx_dev, md_ctrl->hw_info.phy_interrupt_id);
+}
+
+static void t7xx_cldma_disable_irq(struct cldma_ctrl *md_ctrl)
+{
+	t7xx_pcie_mac_clear_int(md_ctrl->t7xx_dev, md_ctrl->hw_info.phy_interrupt_id);
+}
+
+static void t7xx_cldma_irq_work_cb(struct cldma_ctrl *md_ctrl)
+{
+	unsigned long l2_tx_int_msk, l2_rx_int_msk, l2_tx_int, l2_rx_int, val;
+	struct t7xx_cldma_hw *hw_info = &md_ctrl->hw_info;
+	int i;
+
+	/* L2 raw interrupt status */
+	l2_tx_int = ioread32(hw_info->ap_pdn_base + REG_CLDMA_L2TISAR0);
+	l2_rx_int = ioread32(hw_info->ap_pdn_base + REG_CLDMA_L2RISAR0);
+	l2_tx_int_msk = ioread32(hw_info->ap_pdn_base + REG_CLDMA_L2TIMR0);
+	l2_rx_int_msk = ioread32(hw_info->ap_ao_base + REG_CLDMA_L2RIMR0);
+	l2_tx_int &= ~l2_tx_int_msk;
+	l2_rx_int &= ~l2_rx_int_msk;
+
+	if (l2_tx_int) {
+		if (l2_tx_int & (TQ_ERR_INT_BITMASK | TQ_ACTIVE_START_ERR_INT_BITMASK)) {
+			/* Read and clear L3 TX interrupt status */
+			val = ioread32(hw_info->ap_pdn_base + REG_CLDMA_L3TISAR0);
+			iowrite32(val, hw_info->ap_pdn_base + REG_CLDMA_L3TISAR0);
+			val = ioread32(hw_info->ap_pdn_base + REG_CLDMA_L3TISAR1);
+			iowrite32(val, hw_info->ap_pdn_base + REG_CLDMA_L3TISAR1);
+		}
+
+		t7xx_cldma_hw_tx_done(hw_info, l2_tx_int);
+		if (l2_tx_int & (TXRX_STATUS_BITMASK | EMPTY_STATUS_BITMASK)) {
+			for_each_set_bit(i, &l2_tx_int, L2_INT_BIT_COUNT) {
+				if (i < CLDMA_TXQ_NUM) {
+					t7xx_cldma_hw_irq_dis_eq(hw_info, i, MTK_TX);
+					t7xx_cldma_hw_irq_dis_txrx(hw_info, i, MTK_TX);
+					queue_work(md_ctrl->txq[i].worker,
+						   &md_ctrl->txq[i].cldma_work);
+				} else {
+					t7xx_cldma_txq_empty_hndl(&md_ctrl->txq[i - CLDMA_TXQ_NUM]);
+				}
+			}
+		}
+	}
+
+	if (l2_rx_int) {
+		if (l2_rx_int & (RQ_ERR_INT_BITMASK | RQ_ACTIVE_START_ERR_INT_BITMASK)) {
+			/* Read and clear L3 RX interrupt status */
+			val = ioread32(hw_info->ap_pdn_base + REG_CLDMA_L3RISAR0);
+			iowrite32(val, hw_info->ap_pdn_base + REG_CLDMA_L3RISAR0);
+			val = ioread32(hw_info->ap_pdn_base + REG_CLDMA_L3RISAR1);
+			iowrite32(val, hw_info->ap_pdn_base + REG_CLDMA_L3RISAR1);
+		}
+
+		t7xx_cldma_hw_rx_done(hw_info, l2_rx_int);
+		if (l2_rx_int & (TXRX_STATUS_BITMASK | EMPTY_STATUS_BITMASK)) {
+			l2_rx_int |= l2_rx_int >> CLDMA_RXQ_NUM;
+			for_each_set_bit(i, &l2_rx_int, CLDMA_RXQ_NUM) {
+				t7xx_cldma_hw_irq_dis_eq(hw_info, i, MTK_RX);
+				t7xx_cldma_hw_irq_dis_txrx(hw_info, i, MTK_RX);
+				queue_work(md_ctrl->rxq[i].worker, &md_ctrl->rxq[i].cldma_work);
+			}
+		}
+	}
+}
+
+static bool t7xx_cldma_qs_are_active(struct cldma_ctrl *md_ctrl)
+{
+	struct t7xx_cldma_hw *hw_info = &md_ctrl->hw_info;
+	unsigned int tx_active;
+	unsigned int rx_active;
+
+	if (!pci_device_is_present(to_pci_dev(md_ctrl->dev)))
+		return false;
+
+	tx_active = t7xx_cldma_hw_queue_status(hw_info, CLDMA_ALL_Q, MTK_TX);
+	rx_active = t7xx_cldma_hw_queue_status(hw_info, CLDMA_ALL_Q, MTK_RX);
+
+	return tx_active || rx_active;
+}
+
+/**
+ * t7xx_cldma_stop() - Stop CLDMA.
+ * @md_ctrl: CLDMA context structure.
+ *
+ * Stop TX and RX queues. Disable L1 and L2 interrupts.
+ * Clear status registers.
+ *
+ * Return:
+ * * 0		- Success.
+ * * -ERROR	- Error code from polling cldma_queues_active.
+ */
+int t7xx_cldma_stop(struct cldma_ctrl *md_ctrl)
+{
+	struct t7xx_cldma_hw *hw_info = &md_ctrl->hw_info;
+	bool active;
+	int i, ret;
+
+	md_ctrl->rxq_active = 0;
+	t7xx_cldma_hw_stop_all_qs(hw_info, MTK_RX);
+	md_ctrl->txq_active = 0;
+	t7xx_cldma_hw_stop_all_qs(hw_info, MTK_TX);
+	md_ctrl->txq_started = 0;
+	t7xx_cldma_disable_irq(md_ctrl);
+	t7xx_cldma_hw_stop(hw_info, MTK_RX);
+	t7xx_cldma_hw_stop(hw_info, MTK_TX);
+	t7xx_cldma_hw_tx_done(hw_info, CLDMA_L2TISAR0_ALL_INT_MASK);
+	t7xx_cldma_hw_rx_done(hw_info, CLDMA_L2RISAR0_ALL_INT_MASK);
+
+	if (md_ctrl->is_late_init) {
+		for (i = 0; i < CLDMA_TXQ_NUM; i++)
+			flush_work(&md_ctrl->txq[i].cldma_work);
+
+		for (i = 0; i < CLDMA_RXQ_NUM; i++)
+			flush_work(&md_ctrl->rxq[i].cldma_work);
+	}
+
+	ret = read_poll_timeout(t7xx_cldma_qs_are_active, active, !active, CHECK_Q_STOP_STEP_US,
+				CHECK_Q_STOP_TIMEOUT_US, true, md_ctrl);
+	if (ret)
+		dev_err(md_ctrl->dev, "Could not stop CLDMA%d queues", md_ctrl->hif_id);
+
+	return ret;
+}
+
+static void t7xx_cldma_late_release(struct cldma_ctrl *md_ctrl)
+{
+	int i;
+
+	if (!md_ctrl->is_late_init)
+		return;
+
+	for (i = 0; i < CLDMA_TXQ_NUM; i++)
+		t7xx_cldma_ring_free(md_ctrl, &md_ctrl->tx_ring[i], DMA_TO_DEVICE);
+
+	for (i = 0; i < CLDMA_RXQ_NUM; i++)
+		t7xx_cldma_ring_free(md_ctrl, &md_ctrl->rx_ring[i], DMA_FROM_DEVICE);
+
+	dma_pool_destroy(md_ctrl->gpd_dmapool);
+	md_ctrl->gpd_dmapool = NULL;
+	md_ctrl->is_late_init = false;
+}
+
+void t7xx_cldma_reset(struct cldma_ctrl *md_ctrl)
+{
+	unsigned long flags;
+	int i;
+
+	spin_lock_irqsave(&md_ctrl->cldma_lock, flags);
+	md_ctrl->txq_active = 0;
+	md_ctrl->rxq_active = 0;
+	t7xx_cldma_disable_irq(md_ctrl);
+	spin_unlock_irqrestore(&md_ctrl->cldma_lock, flags);
+
+	for (i = 0; i < CLDMA_TXQ_NUM; i++) {
+		cancel_work_sync(&md_ctrl->txq[i].cldma_work);
+
+		spin_lock_irqsave(&md_ctrl->cldma_lock, flags);
+		md_cd_queue_struct_reset(&md_ctrl->txq[i], md_ctrl, MTK_TX, i);
+		spin_unlock_irqrestore(&md_ctrl->cldma_lock, flags);
+	}
+
+	for (i = 0; i < CLDMA_RXQ_NUM; i++) {
+		cancel_work_sync(&md_ctrl->rxq[i].cldma_work);
+
+		spin_lock_irqsave(&md_ctrl->cldma_lock, flags);
+		md_cd_queue_struct_reset(&md_ctrl->rxq[i], md_ctrl, MTK_RX, i);
+		spin_unlock_irqrestore(&md_ctrl->cldma_lock, flags);
+	}
+
+	t7xx_cldma_late_release(md_ctrl);
+}
+
+/**
+ * t7xx_cldma_start() - Start CLDMA.
+ * @md_ctrl: CLDMA context structure.
+ *
+ * Set TX/RX start address.
+ * Start all RX queues and enable L2 interrupt.
+ */
+void t7xx_cldma_start(struct cldma_ctrl *md_ctrl)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&md_ctrl->cldma_lock, flags);
+	if (md_ctrl->is_late_init) {
+		struct t7xx_cldma_hw *hw_info = &md_ctrl->hw_info;
+		int i;
+
+		t7xx_cldma_enable_irq(md_ctrl);
+
+		for (i = 0; i < CLDMA_TXQ_NUM; i++) {
+			if (md_ctrl->txq[i].tr_done)
+				t7xx_cldma_hw_set_start_addr(hw_info, i,
+							     md_ctrl->txq[i].tr_done->gpd_addr,
+							     MTK_TX);
+		}
+
+		for (i = 0; i < CLDMA_RXQ_NUM; i++) {
+			if (md_ctrl->rxq[i].tr_done)
+				t7xx_cldma_hw_set_start_addr(hw_info, i,
+							     md_ctrl->rxq[i].tr_done->gpd_addr,
+							     MTK_RX);
+		}
+
+		/* Enable L2 interrupt */
+		t7xx_cldma_hw_start_queue(hw_info, CLDMA_ALL_Q, MTK_RX);
+		t7xx_cldma_hw_start(hw_info);
+		md_ctrl->txq_started = 0;
+		md_ctrl->txq_active |= TXRX_STATUS_BITMASK;
+		md_ctrl->rxq_active |= TXRX_STATUS_BITMASK;
+	}
+	spin_unlock_irqrestore(&md_ctrl->cldma_lock, flags);
+}
+
+static void t7xx_cldma_clear_txq(struct cldma_ctrl *md_ctrl, int qnum)
+{
+	struct cldma_queue *txq = &md_ctrl->txq[qnum];
+	struct cldma_request *req;
+	struct cldma_gpd *gpd;
+	unsigned long flags;
+
+	spin_lock_irqsave(&txq->ring_lock, flags);
+	t7xx_cldma_q_reset(txq);
+	list_for_each_entry(req, &txq->tr_ring->gpd_ring, entry) {
+		gpd = req->gpd;
+		gpd->flags &= ~GPD_FLAGS_HWO;
+		t7xx_cldma_gpd_set_data_ptr(gpd, 0);
+		gpd->data_buff_len = 0;
+		dev_kfree_skb_any(req->skb);
+		req->skb = NULL;
+	}
+	spin_unlock_irqrestore(&txq->ring_lock, flags);
+}
+
+static int t7xx_cldma_clear_rxq(struct cldma_ctrl *md_ctrl, int qnum)
+{
+	struct cldma_queue *rxq = &md_ctrl->rxq[qnum];
+	struct cldma_request *req;
+	struct cldma_gpd *gpd;
+	unsigned long flags;
+	int ret = 0;
+
+	spin_lock_irqsave(&rxq->ring_lock, flags);
+	t7xx_cldma_q_reset(rxq);
+	list_for_each_entry(req, &rxq->tr_ring->gpd_ring, entry) {
+		gpd = req->gpd;
+		gpd->flags = GPD_FLAGS_IOC | GPD_FLAGS_HWO;
+		gpd->data_buff_len = 0;
+
+		if (req->skb) {
+			req->skb->len = 0;
+			skb_reset_tail_pointer(req->skb);
+		}
+	}
+
+	list_for_each_entry(req, &rxq->tr_ring->gpd_ring, entry) {
+		if (req->skb)
+			continue;
+
+		ret = t7xx_cldma_alloc_and_map_skb(md_ctrl, req, rxq->tr_ring->pkt_size);
+		if (ret)
+			break;
+
+		t7xx_cldma_gpd_set_data_ptr(req->gpd, req->mapped_buff);
+	}
+	spin_unlock_irqrestore(&rxq->ring_lock, flags);
+
+	return ret;
+}
+
+void t7xx_cldma_clear_all_qs(struct cldma_ctrl *md_ctrl, enum mtk_txrx tx_rx)
+{
+	int i;
+
+	if (tx_rx == MTK_TX) {
+		for (i = 0; i < CLDMA_TXQ_NUM; i++)
+			t7xx_cldma_clear_txq(md_ctrl, i);
+	} else {
+		for (i = 0; i < CLDMA_RXQ_NUM; i++)
+			t7xx_cldma_clear_rxq(md_ctrl, i);
+	}
+}
+
+void t7xx_cldma_stop_all_qs(struct cldma_ctrl *md_ctrl, enum mtk_txrx tx_rx)
+{
+	struct t7xx_cldma_hw *hw_info = &md_ctrl->hw_info;
+	unsigned long flags;
+
+	spin_lock_irqsave(&md_ctrl->cldma_lock, flags);
+	t7xx_cldma_hw_irq_dis_eq(hw_info, CLDMA_ALL_Q, tx_rx);
+	t7xx_cldma_hw_irq_dis_txrx(hw_info, CLDMA_ALL_Q, tx_rx);
+	if (tx_rx == MTK_RX)
+		md_ctrl->rxq_active &= ~TXRX_STATUS_BITMASK;
+	else
+		md_ctrl->txq_active &= ~TXRX_STATUS_BITMASK;
+	t7xx_cldma_hw_stop_all_qs(hw_info, tx_rx);
+	spin_unlock_irqrestore(&md_ctrl->cldma_lock, flags);
+}
+
+static int t7xx_cldma_gpd_handle_tx_request(struct cldma_queue *queue, struct cldma_request *tx_req,
+					    struct sk_buff *skb)
+{
+	struct cldma_ctrl *md_ctrl = queue->md_ctrl;
+	struct cldma_gpd *gpd = tx_req->gpd;
+	unsigned long flags;
+
+	/* Update GPD */
+	tx_req->mapped_buff = dma_map_single(md_ctrl->dev, skb->data, skb->len, DMA_TO_DEVICE);
+
+	if (dma_mapping_error(md_ctrl->dev, tx_req->mapped_buff)) {
+		dev_err(md_ctrl->dev, "DMA mapping failed\n");
+		return -ENOMEM;
+	}
+
+	t7xx_cldma_gpd_set_data_ptr(gpd, tx_req->mapped_buff);
+	gpd->data_buff_len = cpu_to_le16(skb->len);
+
+	/* This lock must cover TGPD setting, as even without a resume operation,
+	 * CLDMA can send next HWO=1 if last TGPD just finished.
+	 */
+	spin_lock_irqsave(&md_ctrl->cldma_lock, flags);
+	if (md_ctrl->txq_active & BIT(queue->index))
+		gpd->flags |= GPD_FLAGS_HWO;
+
+	spin_unlock_irqrestore(&md_ctrl->cldma_lock, flags);
+
+	tx_req->skb = skb;
+	return 0;
+}
+
+/* Called with cldma_lock */
+static void t7xx_cldma_hw_start_send(struct cldma_ctrl *md_ctrl, int qno,
+				     struct cldma_request *prev_req)
+{
+	struct t7xx_cldma_hw *hw_info = &md_ctrl->hw_info;
+
+	/* Check whether the device was powered off (CLDMA start address is not set) */
+	if (!t7xx_cldma_tx_addr_is_set(hw_info, qno)) {
+		t7xx_cldma_hw_init(hw_info);
+		t7xx_cldma_hw_set_start_addr(hw_info, qno, prev_req->gpd_addr, MTK_TX);
+		md_ctrl->txq_started &= ~BIT(qno);
+	}
+
+	if (!t7xx_cldma_hw_queue_status(hw_info, qno, MTK_TX)) {
+		if (md_ctrl->txq_started & BIT(qno))
+			t7xx_cldma_hw_resume_queue(hw_info, qno, MTK_TX);
+		else
+			t7xx_cldma_hw_start_queue(hw_info, qno, MTK_TX);
+
+		md_ctrl->txq_started |= BIT(qno);
+	}
+}
+
+/**
+ * t7xx_cldma_set_recv_skb() - Set the callback to handle RX packets.
+ * @md_ctrl: CLDMA context structure.
+ * @recv_skb: Receiving skb callback.
+ */
+void t7xx_cldma_set_recv_skb(struct cldma_ctrl *md_ctrl,
+			     int (*recv_skb)(struct cldma_queue *queue, struct sk_buff *skb))
+{
+	md_ctrl->recv_skb = recv_skb;
+}
+
+/**
+ * t7xx_cldma_send_skb() - Send control data to modem.
+ * @md_ctrl: CLDMA context structure.
+ * @qno: Queue number.
+ * @skb: Socket buffer.
+ *
+ * Return:
+ * * 0		- Success.
+ * * -ENOMEM	- Allocation failure.
+ * * -EINVAL	- Invalid queue request.
+ * * -EIO	- Queue is not active.
+ * * -ETIMEDOUT	- Timeout waiting for the device to wake up.
+ */
+int t7xx_cldma_send_skb(struct cldma_ctrl *md_ctrl, int qno, struct sk_buff *skb)
+{
+	struct cldma_request *tx_req;
+	struct cldma_queue *queue;
+	unsigned long flags;
+	int ret;
+
+	if (qno >= CLDMA_TXQ_NUM)
+		return -EINVAL;
+
+	queue = &md_ctrl->txq[qno];
+
+	spin_lock_irqsave(&md_ctrl->cldma_lock, flags);
+	if (!(md_ctrl->txq_active & BIT(qno))) {
+		ret = -EIO;
+		spin_unlock_irqrestore(&md_ctrl->cldma_lock, flags);
+		goto allow_sleep;
+	}
+	spin_unlock_irqrestore(&md_ctrl->cldma_lock, flags);
+
+	do {
+		spin_lock_irqsave(&queue->ring_lock, flags);
+		tx_req = queue->tx_next;
+		if (queue->budget > 0 && !tx_req->skb) {
+			struct list_head *gpd_ring = &queue->tr_ring->gpd_ring;
+
+			queue->budget--;
+			t7xx_cldma_gpd_handle_tx_request(queue, tx_req, skb);
+			queue->tx_next = list_next_entry_circular(tx_req, gpd_ring, entry);
+			spin_unlock_irqrestore(&queue->ring_lock, flags);
+
+			/* Protect the access to the modem for queues operations (resume/start)
+			 * which access shared locations by all the queues.
+			 * cldma_lock is independent of ring_lock which is per queue.
+			 */
+			spin_lock_irqsave(&md_ctrl->cldma_lock, flags);
+			t7xx_cldma_hw_start_send(md_ctrl, qno, tx_req);
+			spin_unlock_irqrestore(&md_ctrl->cldma_lock, flags);
+
+			break;
+		}
+		spin_unlock_irqrestore(&queue->ring_lock, flags);
+
+		if (!t7xx_cldma_hw_queue_status(&md_ctrl->hw_info, qno, MTK_TX)) {
+			spin_lock_irqsave(&md_ctrl->cldma_lock, flags);
+			t7xx_cldma_hw_resume_queue(&md_ctrl->hw_info, qno, MTK_TX);
+			spin_unlock_irqrestore(&md_ctrl->cldma_lock, flags);
+		}
+
+		ret = wait_event_interruptible_exclusive(queue->req_wq, queue->budget > 0);
+	} while (!ret);
+
+allow_sleep:
+	return ret;
+}
+
+static int t7xx_cldma_late_init(struct cldma_ctrl *md_ctrl)
+{
+	char dma_pool_name[32];
+	int i, j, ret;
+
+	if (md_ctrl->is_late_init) {
+		dev_err(md_ctrl->dev, "CLDMA late init was already done\n");
+		return -EALREADY;
+	}
+
+	snprintf(dma_pool_name, sizeof(dma_pool_name), "cldma_req_hif%d", md_ctrl->hif_id);
+
+	md_ctrl->gpd_dmapool = dma_pool_create(dma_pool_name, md_ctrl->dev,
+					       sizeof(struct cldma_gpd), GPD_DMAPOOL_ALIGN, 0);
+	if (!md_ctrl->gpd_dmapool) {
+		dev_err(md_ctrl->dev, "DMA pool alloc fail\n");
+		return -ENOMEM;
+	}
+
+	for (i = 0; i < CLDMA_TXQ_NUM; i++) {
+		ret = t7xx_cldma_tx_ring_init(md_ctrl, &md_ctrl->tx_ring[i]);
+		if (ret) {
+			dev_err(md_ctrl->dev, "control TX ring init fail\n");
+			goto err_free_tx_ring;
+		}
+	}
+
+	for (j = 0; j < CLDMA_RXQ_NUM; j++) {
+		md_ctrl->rx_ring[j].pkt_size = CLDMA_MTU;
+
+		if (j == CLDMA_RXQ_NUM - 1)
+			md_ctrl->rx_ring[j].pkt_size = CLDMA_JUMBO_BUFF_SZ;
+
+		ret = t7xx_cldma_rx_ring_init(md_ctrl, &md_ctrl->rx_ring[j]);
+		if (ret) {
+			dev_err(md_ctrl->dev, "Control RX ring init fail\n");
+			goto err_free_rx_ring;
+		}
+	}
+
+	for (i = 0; i < CLDMA_TXQ_NUM; i++)
+		t7xx_cldma_txq_init(&md_ctrl->txq[i]);
+
+	for (j = 0; j < CLDMA_RXQ_NUM; j++)
+		t7xx_cldma_rxq_init(&md_ctrl->rxq[j]);
+
+	md_ctrl->is_late_init = true;
+	return 0;
+
+err_free_rx_ring:
+	while (j--)
+		t7xx_cldma_ring_free(md_ctrl, &md_ctrl->rx_ring[j], DMA_FROM_DEVICE);
+
+err_free_tx_ring:
+	while (i--)
+		t7xx_cldma_ring_free(md_ctrl, &md_ctrl->tx_ring[i], DMA_TO_DEVICE);
+
+	return ret;
+}
+
+static void __iomem *t7xx_pcie_addr_transfer(void __iomem *addr, u32 addr_trs1, u32 phy_addr)
+{
+	return addr + phy_addr - addr_trs1;
+}
+
+static void t7xx_hw_info_init(struct cldma_ctrl *md_ctrl)
+{
+	struct t7xx_addr_base *pbase = &md_ctrl->t7xx_dev->base_addr;
+	struct t7xx_cldma_hw *hw_info = &md_ctrl->hw_info;
+	u32 phy_ao_base, phy_pd_base;
+
+	if (md_ctrl->hif_id != CLDMA_ID_MD)
+		return;
+
+	phy_ao_base = CLDMA1_AO_BASE;
+	phy_pd_base = CLDMA1_PD_BASE;
+	hw_info->phy_interrupt_id = CLDMA1_INT;
+	hw_info->hw_mode = MODE_BIT_64;
+	hw_info->ap_ao_base = t7xx_pcie_addr_transfer(pbase->pcie_ext_reg_base,
+						      pbase->pcie_dev_reg_trsl_addr, phy_ao_base);
+	hw_info->ap_pdn_base = t7xx_pcie_addr_transfer(pbase->pcie_ext_reg_base,
+						       pbase->pcie_dev_reg_trsl_addr, phy_pd_base);
+}
+
+static int t7xx_cldma_default_recv_skb(struct cldma_queue *queue, struct sk_buff *skb)
+{
+	dev_kfree_skb_any(skb);
+	return 0;
+}
+
+int t7xx_cldma_alloc(enum cldma_id hif_id, struct t7xx_pci_dev *t7xx_dev)
+{
+	struct device *dev = &t7xx_dev->pdev->dev;
+	struct cldma_ctrl *md_ctrl;
+
+	md_ctrl = devm_kzalloc(dev, sizeof(*md_ctrl), GFP_KERNEL);
+	if (!md_ctrl)
+		return -ENOMEM;
+
+	md_ctrl->t7xx_dev = t7xx_dev;
+	md_ctrl->dev = dev;
+	md_ctrl->hif_id = hif_id;
+	md_ctrl->recv_skb = t7xx_cldma_default_recv_skb;
+	t7xx_hw_info_init(md_ctrl);
+	t7xx_dev->md->md_ctrl[hif_id] = md_ctrl;
+	return 0;
+}
+
+void t7xx_cldma_hif_hw_init(struct cldma_ctrl *md_ctrl)
+{
+	struct t7xx_cldma_hw *hw_info = &md_ctrl->hw_info;
+	unsigned long flags;
+
+	spin_lock_irqsave(&md_ctrl->cldma_lock, flags);
+	t7xx_cldma_hw_stop(hw_info, MTK_TX);
+	t7xx_cldma_hw_stop(hw_info, MTK_RX);
+	t7xx_cldma_hw_rx_done(hw_info, EMPTY_STATUS_BITMASK | TXRX_STATUS_BITMASK);
+	t7xx_cldma_hw_tx_done(hw_info, EMPTY_STATUS_BITMASK | TXRX_STATUS_BITMASK);
+	t7xx_cldma_hw_init(hw_info);
+	spin_unlock_irqrestore(&md_ctrl->cldma_lock, flags);
+}
+
+static irqreturn_t t7xx_cldma_isr_handler(int irq, void *data)
+{
+	struct cldma_ctrl *md_ctrl = data;
+	u32 interrupt;
+
+	interrupt = md_ctrl->hw_info.phy_interrupt_id;
+	t7xx_pcie_mac_clear_int(md_ctrl->t7xx_dev, interrupt);
+	t7xx_cldma_irq_work_cb(md_ctrl);
+	t7xx_pcie_mac_clear_int_status(md_ctrl->t7xx_dev, interrupt);
+	t7xx_pcie_mac_set_int(md_ctrl->t7xx_dev, interrupt);
+	return IRQ_HANDLED;
+}
+
+static void t7xx_cldma_destroy_wqs(struct cldma_ctrl *md_ctrl)
+{
+	int i;
+
+	for (i = 0; i < CLDMA_TXQ_NUM; i++) {
+		if (md_ctrl->txq[i].worker) {
+			destroy_workqueue(md_ctrl->txq[i].worker);
+			md_ctrl->txq[i].worker = NULL;
+		}
+	}
+
+	for (i = 0; i < CLDMA_RXQ_NUM; i++) {
+		if (md_ctrl->rxq[i].worker) {
+			destroy_workqueue(md_ctrl->rxq[i].worker);
+			md_ctrl->rxq[i].worker = NULL;
+		}
+	}
+}
+
+/**
+ * t7xx_cldma_init() - Initialize CLDMA.
+ * @md_ctrl: CLDMA context structure.
+ *
+ * Initialize HIF TX/RX queue structure.
+ * Register CLDMA callback ISR with PCIe driver.
+ *
+ * Return:
+ * * 0		- Success.
+ * * -ERROR	- Error code from failure sub-initializations.
+ */
+int t7xx_cldma_init(struct cldma_ctrl *md_ctrl)
+{
+	struct t7xx_cldma_hw *hw_info = &md_ctrl->hw_info;
+	int i;
+
+	md_ctrl->txq_active = 0;
+	md_ctrl->rxq_active = 0;
+	md_ctrl->is_late_init = false;
+
+	spin_lock_init(&md_ctrl->cldma_lock);
+
+	for (i = 0; i < CLDMA_TXQ_NUM; i++) {
+		md_cd_queue_struct_init(&md_ctrl->txq[i], md_ctrl, MTK_TX, i);
+		md_ctrl->txq[i].worker =
+			alloc_workqueue("md_hif%d_tx%d_worker",
+					WQ_UNBOUND | WQ_MEM_RECLAIM | (i ? 0 : WQ_HIGHPRI),
+					1, md_ctrl->hif_id, i);
+		if (!md_ctrl->txq[i].worker)
+			goto err_workqueue;
+
+		INIT_WORK(&md_ctrl->txq[i].cldma_work, t7xx_cldma_tx_done);
+	}
+
+	for (i = 0; i < CLDMA_RXQ_NUM; i++) {
+		md_cd_queue_struct_init(&md_ctrl->rxq[i], md_ctrl, MTK_RX, i);
+		INIT_WORK(&md_ctrl->rxq[i].cldma_work, t7xx_cldma_rx_done);
+
+		md_ctrl->rxq[i].worker = alloc_workqueue("md_hif%d_rx%d_worker",
+							 WQ_UNBOUND | WQ_MEM_RECLAIM,
+							 1, md_ctrl->hif_id, i);
+		if (!md_ctrl->rxq[i].worker)
+			goto err_workqueue;
+	}
+
+	t7xx_pcie_mac_clear_int(md_ctrl->t7xx_dev, hw_info->phy_interrupt_id);
+	md_ctrl->t7xx_dev->intr_handler[hw_info->phy_interrupt_id] = t7xx_cldma_isr_handler;
+	md_ctrl->t7xx_dev->intr_thread[hw_info->phy_interrupt_id] = NULL;
+	md_ctrl->t7xx_dev->callback_param[hw_info->phy_interrupt_id] = md_ctrl;
+	t7xx_pcie_mac_clear_int_status(md_ctrl->t7xx_dev, hw_info->phy_interrupt_id);
+	return 0;
+
+err_workqueue:
+	t7xx_cldma_destroy_wqs(md_ctrl);
+	return -ENOMEM;
+}
+
+void t7xx_cldma_switch_cfg(struct cldma_ctrl *md_ctrl)
+{
+	t7xx_cldma_late_release(md_ctrl);
+	t7xx_cldma_late_init(md_ctrl);
+}
+
+void t7xx_cldma_exit(struct cldma_ctrl *md_ctrl)
+{
+	t7xx_cldma_stop(md_ctrl);
+	t7xx_cldma_late_release(md_ctrl);
+	t7xx_cldma_destroy_wqs(md_ctrl);
+}

drivers/net/wwan/t7xx/t7xx_hif_cldma.h

···
+/* SPDX-License-Identifier: GPL-2.0-only
+ *
+ * Copyright (c) 2021, MediaTek Inc.
+ * Copyright (c) 2021-2022, Intel Corporation.
+ *
+ * Authors:
+ *  Haijun Liu <[e-mail]>
+ *  Moises Veleta <[e-mail]>
+ *  Ricardo Martinez <[e-mail]>
+ *  Sreehari Kancharla <[e-mail]>
+ *
+ * Contributors:
+ *  Amir Hanania <[e-mail]>
+ *  Chiranjeevi Rapolu <[e-mail]>
+ *  Eliot Lee <[e-mail]>
+ */
+
+#ifndef __T7XX_HIF_CLDMA_H__
+#define __T7XX_HIF_CLDMA_H__
+
+#include <linux/bits.h>
+#include <linux/device.h>
+#include <linux/dmapool.h>
+#include <linux/pci.h>
+#include <linux/skbuff.h>
+#include <linux/spinlock.h>
+#include <linux/wait.h>
+#include <linux/workqueue.h>
+#include <linux/types.h>
+
+#include "t7xx_cldma.h"
+#include "t7xx_pci.h"
+
+/**
+ * enum cldma_id - Identifiers for CLDMA HW units.
+ * @CLDMA_ID_MD: Modem control channel.
+ * @CLDMA_ID_AP: Application Processor control channel (not used at the moment).
+ * @CLDMA_NUM:   Number of CLDMA HW units available.
+ */
+enum cldma_id {
+	CLDMA_ID_MD,
+	CLDMA_ID_AP,
+	CLDMA_NUM
+};
+
+struct cldma_gpd {
+	u8 flags;
+	u8 not_used1;
+	__le16 rx_data_allow_len;
+	__le32 next_gpd_ptr_h;
+	__le32 next_gpd_ptr_l;
+	__le32 data_buff_bd_ptr_h;
+	__le32 data_buff_bd_ptr_l;
+	__le16 data_buff_len;
+	__le16 not_used2;
+};
+
+struct cldma_request {
+	struct cldma_gpd *gpd;	/* Virtual address for CPU */
+	dma_addr_t gpd_addr;	/* Physical address for DMA */
+	struct sk_buff *skb;
+	dma_addr_t mapped_buff;
+	struct list_head entry;
+};
+
+struct cldma_ring {
+	struct list_head gpd_ring;	/* Ring of struct cldma_request */
+	unsigned int length;		/* Number of struct cldma_request */
+	int pkt_size;
+};
+
+struct cldma_queue {
+	struct cldma_ctrl *md_ctrl;
+	enum mtk_txrx dir;
+	unsigned int index;
+	struct cldma_ring *tr_ring;
+	struct cldma_request *tr_done;
+	struct cldma_request *rx_refill;
+	struct cldma_request *tx_next;
+	int budget;			/* Same as ring buffer size by default */
+	spinlock_t ring_lock;
+	wait_queue_head_t req_wq;	/* Only for TX */
+	struct workqueue_struct *worker;
+	struct work_struct cldma_work;
+};
+
+struct cldma_ctrl {
+	enum cldma_id hif_id;
+	struct device *dev;
+	struct t7xx_pci_dev *t7xx_dev;
+	struct cldma_queue txq[CLDMA_TXQ_NUM];
+	struct cldma_queue rxq[CLDMA_RXQ_NUM];
+	unsigned short txq_active;
+	unsigned short rxq_active;
+	unsigned short txq_started;
+	spinlock_t cldma_lock; /* Protects CLDMA structure */
+	/* Assumes T/R GPD/BD/SPD have the same size */
+	struct dma_pool *gpd_dmapool;
+	struct cldma_ring tx_ring[CLDMA_TXQ_NUM];
+	struct cldma_ring rx_ring[CLDMA_RXQ_NUM];
+	struct t7xx_cldma_hw hw_info;
+	bool is_late_init;
+	int (*recv_skb)(struct cldma_queue *queue, struct sk_buff *skb);
+};
+
+#define GPD_FLAGS_HWO		BIT(0)
+#define GPD_FLAGS_IOC		BIT(7)
+#define GPD_DMAPOOL_ALIGN	16
+
+#define CLDMA_MTU		3584	/* 3.5kB */
+
+int t7xx_cldma_alloc(enum cldma_id hif_id, struct t7xx_pci_dev *t7xx_dev);
+void t7xx_cldma_hif_hw_init(struct cldma_ctrl *md_ctrl);
+int t7xx_cldma_init(struct cldma_ctrl *md_ctrl);
+void t7xx_cldma_exit(struct cldma_ctrl *md_ctrl);
+void t7xx_cldma_switch_cfg(struct cldma_ctrl *md_ctrl);
+void t7xx_cldma_start(struct cldma_ctrl *md_ctrl);
+int t7xx_cldma_stop(struct cldma_ctrl *md_ctrl);
+void t7xx_cldma_reset(struct cldma_ctrl *md_ctrl);
+void t7xx_cldma_set_recv_skb(struct cldma_ctrl *md_ctrl,
+			     int (*recv_skb)(struct cldma_queue *queue, struct sk_buff *skb));
+int t7xx_cldma_send_skb(struct cldma_ctrl *md_ctrl, int qno, struct sk_buff *skb);
+void t7xx_cldma_stop_all_qs(struct cldma_ctrl *md_ctrl, enum mtk_txrx tx_rx);
+void t7xx_cldma_clear_all_qs(struct cldma_ctrl *md_ctrl, enum mtk_txrx tx_rx);
+
+#endif /* __T7XX_HIF_CLDMA_H__ */

drivers/net/wwan/t7xx/t7xx_reg.h

···
+/* SPDX-License-Identifier: GPL-2.0-only
+ *
+ * Copyright (c) 2021, MediaTek Inc.
+ * Copyright (c) 2021-2022, Intel Corporation.
+ *
+ * Authors:
+ *  Haijun Liu <[e-mail]>
+ *  Chiranjeevi Rapolu <[e-mail]>
+ *
+ * Contributors:
+ *  Amir Hanania <[e-mail]>
+ *  Andy Shevchenko <[e-mail]>
+ *  Eliot Lee <[e-mail]>
+ *  Moises Veleta <[e-mail]>
+ *  Ricardo Martinez <[e-mail]>
+ *  Sreehari Kancharla <[e-mail]>
+ */
+
+#ifndef __T7XX_REG_H__
+#define __T7XX_REG_H__
+
+enum t7xx_int {
+	DPMAIF_INT,
+	CLDMA0_INT,
+	CLDMA1_INT,
+	CLDMA2_INT,
+	MHCCIF_INT,
+	DPMAIF2_INT,
+	SAP_RGU_INT,
+	CLDMA3_INT,
+};
+
+#endif /* __T7XX_REG_H__ */