// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
/* Copyright(c) 2018-2019  Realtek Corporation
 */

#include <linux/module.h>
#include <linux/pci.h>
#include "main.h"
#include "pci.h"
#include "reg.h"
#include "tx.h"
#include "rx.h"
#include "fw.h"
#include "ps.h"
#include "debug.h"

static bool rtw_disable_msi;
static bool rtw_pci_disable_aspm;
module_param_named(disable_msi, rtw_disable_msi, bool, 0644);
module_param_named(disable_aspm, rtw_pci_disable_aspm, bool, 0644);
MODULE_PARM_DESC(disable_msi, "Set Y to disable MSI interrupt support");
MODULE_PARM_DESC(disable_aspm, "Set Y to disable PCI ASPM support");

static u32 rtw_pci_tx_queue_idx_addr[] = {
        [RTW_TX_QUEUE_BK]       = RTK_PCI_TXBD_IDX_BKQ,
        [RTW_TX_QUEUE_BE]       = RTK_PCI_TXBD_IDX_BEQ,
        [RTW_TX_QUEUE_VI]       = RTK_PCI_TXBD_IDX_VIQ,
        [RTW_TX_QUEUE_VO]       = RTK_PCI_TXBD_IDX_VOQ,
        [RTW_TX_QUEUE_MGMT]     = RTK_PCI_TXBD_IDX_MGMTQ,
        [RTW_TX_QUEUE_HI0]      = RTK_PCI_TXBD_IDX_HI0Q,
        [RTW_TX_QUEUE_H2C]      = RTK_PCI_TXBD_IDX_H2CQ,
};

static u8 rtw_pci_get_tx_qsel(struct sk_buff *skb, u8 queue)
{
        switch (queue) {
        case RTW_TX_QUEUE_BCN:
                return TX_DESC_QSEL_BEACON;
        case RTW_TX_QUEUE_H2C:
                return TX_DESC_QSEL_H2C;
        case RTW_TX_QUEUE_MGMT:
                return TX_DESC_QSEL_MGMT;
        case RTW_TX_QUEUE_HI0:
                return TX_DESC_QSEL_HIGH;
        default:
                return skb->priority;
        }
};

static u8 rtw_pci_read8(struct rtw_dev *rtwdev, u32 addr)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;

        return readb(rtwpci->mmap + addr);
}

static u16 rtw_pci_read16(struct rtw_dev *rtwdev, u32 addr)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;

        return readw(rtwpci->mmap + addr);
}

static u32 rtw_pci_read32(struct rtw_dev *rtwdev, u32 addr)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;

        return readl(rtwpci->mmap + addr);
}

static void rtw_pci_write8(struct rtw_dev *rtwdev, u32 addr, u8 val)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;

        writeb(val, rtwpci->mmap + addr);
}

static void rtw_pci_write16(struct rtw_dev *rtwdev, u32 addr, u16 val)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;

        writew(val, rtwpci->mmap + addr);
}

static void rtw_pci_write32(struct rtw_dev *rtwdev, u32 addr, u32 val)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;

        writel(val, rtwpci->mmap + addr);
}

static inline void *rtw_pci_get_tx_desc(struct rtw_pci_tx_ring *tx_ring, u8 idx)
{
        int offset = tx_ring->r.desc_size * idx;

        return tx_ring->r.head + offset;
}

static void rtw_pci_free_tx_ring_skbs(struct rtw_dev *rtwdev,
                                      struct rtw_pci_tx_ring *tx_ring)
{
        struct pci_dev *pdev = to_pci_dev(rtwdev->dev);
        struct rtw_pci_tx_data *tx_data;
        struct sk_buff *skb, *tmp;
        dma_addr_t dma;

        /* free every skb remained in tx list */
        skb_queue_walk_safe(&tx_ring->queue, skb, tmp) {
                __skb_unlink(skb, &tx_ring->queue);
                tx_data = rtw_pci_get_tx_data(skb);
                dma = tx_data->dma;

                pci_unmap_single(pdev, dma, skb->len, PCI_DMA_TODEVICE);
                dev_kfree_skb_any(skb);
        }
}

static void rtw_pci_free_tx_ring(struct rtw_dev *rtwdev,
                                 struct rtw_pci_tx_ring *tx_ring)
{
        struct pci_dev *pdev = to_pci_dev(rtwdev->dev);
        u8 *head = tx_ring->r.head;
        u32 len = tx_ring->r.len;
        int ring_sz = len * tx_ring->r.desc_size;

        rtw_pci_free_tx_ring_skbs(rtwdev, tx_ring);

        /* free the ring itself */
        pci_free_consistent(pdev, ring_sz, head, tx_ring->r.dma);
        tx_ring->r.head = NULL;
}

static void rtw_pci_free_rx_ring_skbs(struct rtw_dev *rtwdev,
                                      struct rtw_pci_rx_ring *rx_ring)
{
        struct pci_dev *pdev = to_pci_dev(rtwdev->dev);
        struct sk_buff *skb;
        int buf_sz = RTK_PCI_RX_BUF_SIZE;
        dma_addr_t dma;
        int i;

        for (i = 0; i < rx_ring->r.len; i++) {
                skb = rx_ring->buf[i];
                if (!skb)
                        continue;

                dma = *((dma_addr_t *)skb->cb);
                pci_unmap_single(pdev, dma, buf_sz, PCI_DMA_FROMDEVICE);
                dev_kfree_skb(skb);
                rx_ring->buf[i] = NULL;
        }
}

static void rtw_pci_free_rx_ring(struct rtw_dev *rtwdev,
                                 struct rtw_pci_rx_ring *rx_ring)
{
        struct pci_dev *pdev = to_pci_dev(rtwdev->dev);
        u8 *head = rx_ring->r.head;
        int ring_sz = rx_ring->r.desc_size * rx_ring->r.len;

        rtw_pci_free_rx_ring_skbs(rtwdev, rx_ring);

        pci_free_consistent(pdev, ring_sz, head, rx_ring->r.dma);
}

static void rtw_pci_free_trx_ring(struct rtw_dev *rtwdev)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;
        struct rtw_pci_tx_ring *tx_ring;
        struct rtw_pci_rx_ring *rx_ring;
        int i;

        for (i = 0; i < RTK_MAX_TX_QUEUE_NUM; i++) {
                tx_ring = &rtwpci->tx_rings[i];
                rtw_pci_free_tx_ring(rtwdev, tx_ring);
        }

        for (i = 0; i < RTK_MAX_RX_QUEUE_NUM; i++) {
                rx_ring = &rtwpci->rx_rings[i];
                rtw_pci_free_rx_ring(rtwdev, rx_ring);
        }
}

static int rtw_pci_init_tx_ring(struct rtw_dev *rtwdev,
                                struct rtw_pci_tx_ring *tx_ring,
                                u8 desc_size, u32 len)
{
        struct pci_dev *pdev = to_pci_dev(rtwdev->dev);
        int ring_sz = desc_size * len;
        dma_addr_t dma;
        u8 *head;

        if (len > TRX_BD_IDX_MASK) {
                rtw_err(rtwdev, "len %d exceeds maximum TX entries\n", len);
                return -EINVAL;
        }

        head = pci_zalloc_consistent(pdev, ring_sz, &dma);
        if (!head) {
                rtw_err(rtwdev, "failed to allocate tx ring\n");
                return -ENOMEM;
        }

        skb_queue_head_init(&tx_ring->queue);
        tx_ring->r.head = head;
        tx_ring->r.dma = dma;
        tx_ring->r.len = len;
        tx_ring->r.desc_size = desc_size;
        tx_ring->r.wp = 0;
        tx_ring->r.rp = 0;

        return 0;
}

static int rtw_pci_reset_rx_desc(struct rtw_dev *rtwdev, struct sk_buff *skb,
                                 struct rtw_pci_rx_ring *rx_ring,
                                 u32 idx, u32 desc_sz)
{
        struct pci_dev *pdev = to_pci_dev(rtwdev->dev);
        struct rtw_pci_rx_buffer_desc *buf_desc;
        int buf_sz = RTK_PCI_RX_BUF_SIZE;
        dma_addr_t dma;

        if (!skb)
                return -EINVAL;

        dma = pci_map_single(pdev, skb->data, buf_sz, PCI_DMA_FROMDEVICE);
        if (pci_dma_mapping_error(pdev, dma))
                return -EBUSY;

        *((dma_addr_t *)skb->cb) = dma;
        buf_desc = (struct rtw_pci_rx_buffer_desc *)(rx_ring->r.head +
                                                     idx * desc_sz);
        memset(buf_desc, 0, sizeof(*buf_desc));
        buf_desc->buf_size = cpu_to_le16(RTK_PCI_RX_BUF_SIZE);
        buf_desc->dma = cpu_to_le32(dma);

        return 0;
}

static void rtw_pci_sync_rx_desc_device(struct rtw_dev *rtwdev, dma_addr_t dma,
                                        struct rtw_pci_rx_ring *rx_ring,
                                        u32 idx, u32 desc_sz)
{
        struct device *dev = rtwdev->dev;
        struct rtw_pci_rx_buffer_desc *buf_desc;
        int buf_sz = RTK_PCI_RX_BUF_SIZE;

        dma_sync_single_for_device(dev, dma, buf_sz, DMA_FROM_DEVICE);

        buf_desc = (struct rtw_pci_rx_buffer_desc *)(rx_ring->r.head +
                                                     idx * desc_sz);
        memset(buf_desc, 0, sizeof(*buf_desc));
        buf_desc->buf_size = cpu_to_le16(RTK_PCI_RX_BUF_SIZE);
        buf_desc->dma = cpu_to_le32(dma);
}

static int rtw_pci_init_rx_ring(struct rtw_dev *rtwdev,
                                struct rtw_pci_rx_ring *rx_ring,
                                u8 desc_size, u32 len)
{
        struct pci_dev *pdev = to_pci_dev(rtwdev->dev);
        struct sk_buff *skb = NULL;
        dma_addr_t dma;
        u8 *head;
        int ring_sz = desc_size * len;
        int buf_sz = RTK_PCI_RX_BUF_SIZE;
        int i, allocated;
        int ret = 0;

        if (len > TRX_BD_IDX_MASK) {
                rtw_err(rtwdev, "len %d exceeds maximum RX entries\n", len);
                return -EINVAL;
        }

        head = pci_zalloc_consistent(pdev, ring_sz, &dma);
        if (!head) {
                rtw_err(rtwdev, "failed to allocate rx ring\n");
                return -ENOMEM;
        }
        rx_ring->r.head = head;

        for (i = 0; i < len; i++) {
                skb = dev_alloc_skb(buf_sz);
                if (!skb) {
                        allocated = i;
                        ret = -ENOMEM;
                        goto err_out;
                }

                memset(skb->data, 0, buf_sz);
                rx_ring->buf[i] = skb;
                ret = rtw_pci_reset_rx_desc(rtwdev, skb, rx_ring, i, desc_size);
                if (ret) {
                        allocated = i;
                        dev_kfree_skb_any(skb);
                        goto err_out;
                }
        }

        rx_ring->r.dma = dma;
        rx_ring->r.len = len;
        rx_ring->r.desc_size = desc_size;
        rx_ring->r.wp = 0;
        rx_ring->r.rp = 0;

        return 0;

err_out:
        for (i = 0; i < allocated; i++) {
                skb = rx_ring->buf[i];
                if (!skb)
                        continue;
                dma = *((dma_addr_t *)skb->cb);
                pci_unmap_single(pdev, dma, buf_sz, PCI_DMA_FROMDEVICE);
                dev_kfree_skb_any(skb);
                rx_ring->buf[i] = NULL;
        }
        pci_free_consistent(pdev, ring_sz, head, dma);

        rtw_err(rtwdev, "failed to init rx buffer\n");

        return ret;
}

static int rtw_pci_init_trx_ring(struct rtw_dev *rtwdev)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;
        struct rtw_pci_tx_ring *tx_ring;
        struct rtw_pci_rx_ring *rx_ring;
        struct rtw_chip_info *chip = rtwdev->chip;
        int i = 0, j = 0, tx_alloced = 0, rx_alloced = 0;
        int tx_desc_size, rx_desc_size;
        u32 len;
        int ret;

        tx_desc_size = chip->tx_buf_desc_sz;

        for (i = 0; i < RTK_MAX_TX_QUEUE_NUM; i++) {
                tx_ring = &rtwpci->tx_rings[i];
                len = max_num_of_tx_queue(i);
                ret = rtw_pci_init_tx_ring(rtwdev, tx_ring, tx_desc_size, len);
                if (ret)
                        goto out;
        }

        rx_desc_size = chip->rx_buf_desc_sz;

        for (j = 0; j < RTK_MAX_RX_QUEUE_NUM; j++) {
                rx_ring = &rtwpci->rx_rings[j];
                ret = rtw_pci_init_rx_ring(rtwdev, rx_ring, rx_desc_size,
                                           RTK_MAX_RX_DESC_NUM);
                if (ret)
                        goto out;
        }

        return 0;

out:
        tx_alloced = i;
        for (i = 0; i < tx_alloced; i++) {
                tx_ring = &rtwpci->tx_rings[i];
                rtw_pci_free_tx_ring(rtwdev, tx_ring);
        }

        rx_alloced = j;
        for (j = 0; j < rx_alloced; j++) {
                rx_ring = &rtwpci->rx_rings[j];
                rtw_pci_free_rx_ring(rtwdev, rx_ring);
        }

        return ret;
}

static void rtw_pci_deinit(struct rtw_dev *rtwdev)
{
        rtw_pci_free_trx_ring(rtwdev);
}

static int rtw_pci_init(struct rtw_dev *rtwdev)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;
        int ret = 0;

        rtwpci->irq_mask[0] = IMR_HIGHDOK |
                              IMR_MGNTDOK |
                              IMR_BKDOK |
                              IMR_BEDOK |
                              IMR_VIDOK |
                              IMR_VODOK |
                              IMR_ROK |
                              IMR_BCNDMAINT_E |
                              0;
        rtwpci->irq_mask[1] = IMR_TXFOVW |
                              0;
        rtwpci->irq_mask[3] = IMR_H2CDOK |
                              0;
        spin_lock_init(&rtwpci->irq_lock);
        spin_lock_init(&rtwpci->hwirq_lock);
        ret = rtw_pci_init_trx_ring(rtwdev);

        return ret;
}

static void rtw_pci_reset_buf_desc(struct rtw_dev *rtwdev)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;
        u32 len;
        u8 tmp;
        dma_addr_t dma;

        tmp = rtw_read8(rtwdev, RTK_PCI_CTRL + 3);
        rtw_write8(rtwdev, RTK_PCI_CTRL + 3, tmp | 0xf7);

        dma = rtwpci->tx_rings[RTW_TX_QUEUE_BCN].r.dma;
        rtw_write32(rtwdev, RTK_PCI_TXBD_DESA_BCNQ, dma);

        if (!rtw_chip_wcpu_11n(rtwdev)) {
                len = rtwpci->tx_rings[RTW_TX_QUEUE_H2C].r.len;
                dma = rtwpci->tx_rings[RTW_TX_QUEUE_H2C].r.dma;
                rtwpci->tx_rings[RTW_TX_QUEUE_H2C].r.rp = 0;
                rtwpci->tx_rings[RTW_TX_QUEUE_H2C].r.wp = 0;
                rtw_write16(rtwdev, RTK_PCI_TXBD_NUM_H2CQ, len & TRX_BD_IDX_MASK);
                rtw_write32(rtwdev, RTK_PCI_TXBD_DESA_H2CQ, dma);
        }

        len = rtwpci->tx_rings[RTW_TX_QUEUE_BK].r.len;
        dma = rtwpci->tx_rings[RTW_TX_QUEUE_BK].r.dma;
        rtwpci->tx_rings[RTW_TX_QUEUE_BK].r.rp = 0;
        rtwpci->tx_rings[RTW_TX_QUEUE_BK].r.wp = 0;
        rtw_write16(rtwdev, RTK_PCI_TXBD_NUM_BKQ, len & TRX_BD_IDX_MASK);
        rtw_write32(rtwdev, RTK_PCI_TXBD_DESA_BKQ, dma);

        len = rtwpci->tx_rings[RTW_TX_QUEUE_BE].r.len;
        dma = rtwpci->tx_rings[RTW_TX_QUEUE_BE].r.dma;
        rtwpci->tx_rings[RTW_TX_QUEUE_BE].r.rp = 0;
        rtwpci->tx_rings[RTW_TX_QUEUE_BE].r.wp = 0;
        rtw_write16(rtwdev, RTK_PCI_TXBD_NUM_BEQ, len & TRX_BD_IDX_MASK);
        rtw_write32(rtwdev, RTK_PCI_TXBD_DESA_BEQ, dma);

        len = rtwpci->tx_rings[RTW_TX_QUEUE_VO].r.len;
        dma = rtwpci->tx_rings[RTW_TX_QUEUE_VO].r.dma;
        rtwpci->tx_rings[RTW_TX_QUEUE_VO].r.rp = 0;
        rtwpci->tx_rings[RTW_TX_QUEUE_VO].r.wp = 0;
        rtw_write16(rtwdev, RTK_PCI_TXBD_NUM_VOQ, len & TRX_BD_IDX_MASK);
        rtw_write32(rtwdev, RTK_PCI_TXBD_DESA_VOQ, dma);

        len = rtwpci->tx_rings[RTW_TX_QUEUE_VI].r.len;
        dma = rtwpci->tx_rings[RTW_TX_QUEUE_VI].r.dma;
        rtwpci->tx_rings[RTW_TX_QUEUE_VI].r.rp = 0;
        rtwpci->tx_rings[RTW_TX_QUEUE_VI].r.wp = 0;
        rtw_write16(rtwdev, RTK_PCI_TXBD_NUM_VIQ, len & TRX_BD_IDX_MASK);
        rtw_write32(rtwdev, RTK_PCI_TXBD_DESA_VIQ, dma);

        len = rtwpci->tx_rings[RTW_TX_QUEUE_MGMT].r.len;
        dma = rtwpci->tx_rings[RTW_TX_QUEUE_MGMT].r.dma;
        rtwpci->tx_rings[RTW_TX_QUEUE_MGMT].r.rp = 0;
        rtwpci->tx_rings[RTW_TX_QUEUE_MGMT].r.wp = 0;
        rtw_write16(rtwdev, RTK_PCI_TXBD_NUM_MGMTQ, len & TRX_BD_IDX_MASK);
        rtw_write32(rtwdev, RTK_PCI_TXBD_DESA_MGMTQ, dma);

        len = rtwpci->tx_rings[RTW_TX_QUEUE_HI0].r.len;
        dma = rtwpci->tx_rings[RTW_TX_QUEUE_HI0].r.dma;
        rtwpci->tx_rings[RTW_TX_QUEUE_HI0].r.rp = 0;
        rtwpci->tx_rings[RTW_TX_QUEUE_HI0].r.wp = 0;
        rtw_write16(rtwdev, RTK_PCI_TXBD_NUM_HI0Q, len & TRX_BD_IDX_MASK);
        rtw_write32(rtwdev, RTK_PCI_TXBD_DESA_HI0Q, dma);

        len = rtwpci->rx_rings[RTW_RX_QUEUE_MPDU].r.len;
        dma = rtwpci->rx_rings[RTW_RX_QUEUE_MPDU].r.dma;
        rtwpci->rx_rings[RTW_RX_QUEUE_MPDU].r.rp = 0;
        rtwpci->rx_rings[RTW_RX_QUEUE_MPDU].r.wp = 0;
        rtw_write16(rtwdev, RTK_PCI_RXBD_NUM_MPDUQ, len & TRX_BD_IDX_MASK);
        rtw_write32(rtwdev, RTK_PCI_RXBD_DESA_MPDUQ, dma);

        /* reset read/write point */
        rtw_write32(rtwdev, RTK_PCI_TXBD_RWPTR_CLR, 0xffffffff);

        /* reset H2C Queue index in a single write */
        if (rtw_chip_wcpu_11ac(rtwdev))
                rtw_write32_set(rtwdev, RTK_PCI_TXBD_H2CQ_CSR,
                                BIT_CLR_H2CQ_HOST_IDX | BIT_CLR_H2CQ_HW_IDX);
}

static void rtw_pci_reset_trx_ring(struct rtw_dev *rtwdev)
{
        rtw_pci_reset_buf_desc(rtwdev);
}

static void rtw_pci_enable_interrupt(struct rtw_dev *rtwdev,
                                     struct rtw_pci *rtwpci)
{
        unsigned long flags;

        spin_lock_irqsave(&rtwpci->hwirq_lock, flags);

        rtw_write32(rtwdev, RTK_PCI_HIMR0, rtwpci->irq_mask[0]);
        rtw_write32(rtwdev, RTK_PCI_HIMR1, rtwpci->irq_mask[1]);
        if (rtw_chip_wcpu_11ac(rtwdev))
                rtw_write32(rtwdev, RTK_PCI_HIMR3, rtwpci->irq_mask[3]);

        rtwpci->irq_enabled = true;

        spin_unlock_irqrestore(&rtwpci->hwirq_lock, flags);
}

static void rtw_pci_disable_interrupt(struct rtw_dev *rtwdev,
                                      struct rtw_pci *rtwpci)
{
        unsigned long flags;

        spin_lock_irqsave(&rtwpci->hwirq_lock, flags);

        if (!rtwpci->irq_enabled)
                goto out;

        rtw_write32(rtwdev, RTK_PCI_HIMR0, 0);
        rtw_write32(rtwdev, RTK_PCI_HIMR1, 0);
        if (rtw_chip_wcpu_11ac(rtwdev))
                rtw_write32(rtwdev, RTK_PCI_HIMR3, 0);

        rtwpci->irq_enabled = false;

out:
        spin_unlock_irqrestore(&rtwpci->hwirq_lock, flags);
}

static void rtw_pci_dma_reset(struct rtw_dev *rtwdev, struct rtw_pci *rtwpci)
{
        /* reset dma and rx tag */
        rtw_write32_set(rtwdev, RTK_PCI_CTRL,
                        BIT_RST_TRXDMA_INTF | BIT_RX_TAG_EN);
        rtwpci->rx_tag = 0;
}

static int rtw_pci_setup(struct rtw_dev *rtwdev)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;

        rtw_pci_reset_trx_ring(rtwdev);
        rtw_pci_dma_reset(rtwdev, rtwpci);

        return 0;
}

static void rtw_pci_dma_release(struct rtw_dev *rtwdev, struct rtw_pci *rtwpci)
{
        struct rtw_pci_tx_ring *tx_ring;
        u8 queue;

        rtw_pci_reset_trx_ring(rtwdev);
        for (queue = 0; queue < RTK_MAX_TX_QUEUE_NUM; queue++) {
                tx_ring = &rtwpci->tx_rings[queue];
                rtw_pci_free_tx_ring_skbs(rtwdev, tx_ring);
        }
}

static int rtw_pci_start(struct rtw_dev *rtwdev)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;

        spin_lock_bh(&rtwpci->irq_lock);
        rtw_pci_enable_interrupt(rtwdev, rtwpci);
        spin_unlock_bh(&rtwpci->irq_lock);

        return 0;
}

static void rtw_pci_stop(struct rtw_dev *rtwdev)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;

        spin_lock_bh(&rtwpci->irq_lock);
        rtw_pci_disable_interrupt(rtwdev, rtwpci);
        rtw_pci_dma_release(rtwdev, rtwpci);
        spin_unlock_bh(&rtwpci->irq_lock);
}

static void rtw_pci_deep_ps_enter(struct rtw_dev *rtwdev)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;
        struct rtw_pci_tx_ring *tx_ring;
        bool tx_empty = true;
        u8 queue;

        lockdep_assert_held(&rtwpci->irq_lock);

        /* Deep PS state is not allowed to TX-DMA */
        for (queue = 0; queue < RTK_MAX_TX_QUEUE_NUM; queue++) {
                /* BCN queue is rsvd page, does not have DMA interrupt
                 * H2C queue is managed by firmware
                 */
                if (queue == RTW_TX_QUEUE_BCN ||
                    queue == RTW_TX_QUEUE_H2C)
                        continue;

                tx_ring = &rtwpci->tx_rings[queue];

                /* check if there is any skb DMAing */
                if (skb_queue_len(&tx_ring->queue)) {
                        tx_empty = false;
                        break;
                }
        }

        if (!tx_empty) {
                rtw_dbg(rtwdev, RTW_DBG_PS,
                        "TX path not empty, cannot enter deep power save state\n");
                return;
        }

        set_bit(RTW_FLAG_LEISURE_PS_DEEP, rtwdev->flags);
        rtw_power_mode_change(rtwdev, true);
}

static void rtw_pci_deep_ps_leave(struct rtw_dev *rtwdev)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;

        lockdep_assert_held(&rtwpci->irq_lock);

        if (test_and_clear_bit(RTW_FLAG_LEISURE_PS_DEEP, rtwdev->flags))
                rtw_power_mode_change(rtwdev, false);
}

static void rtw_pci_deep_ps(struct rtw_dev *rtwdev, bool enter)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;

        spin_lock_bh(&rtwpci->irq_lock);

        if (enter && !test_bit(RTW_FLAG_LEISURE_PS_DEEP, rtwdev->flags))
                rtw_pci_deep_ps_enter(rtwdev);

        if (!enter && test_bit(RTW_FLAG_LEISURE_PS_DEEP, rtwdev->flags))
                rtw_pci_deep_ps_leave(rtwdev);

        spin_unlock_bh(&rtwpci->irq_lock);
}

static u8 ac_to_hwq[] = {
        [IEEE80211_AC_VO] = RTW_TX_QUEUE_VO,
        [IEEE80211_AC_VI] = RTW_TX_QUEUE_VI,
        [IEEE80211_AC_BE] = RTW_TX_QUEUE_BE,
        [IEEE80211_AC_BK] = RTW_TX_QUEUE_BK,
};

static u8 rtw_hw_queue_mapping(struct sk_buff *skb)
{
        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
        __le16 fc = hdr->frame_control;
        u8 q_mapping = skb_get_queue_mapping(skb);
        u8 queue;

        if (unlikely(ieee80211_is_beacon(fc)))
                queue = RTW_TX_QUEUE_BCN;
        else if (unlikely(ieee80211_is_mgmt(fc) || ieee80211_is_ctl(fc)))
                queue = RTW_TX_QUEUE_MGMT;
        else if (WARN_ON_ONCE(q_mapping >= ARRAY_SIZE(ac_to_hwq)))
                queue = ac_to_hwq[IEEE80211_AC_BE];
        else
                queue = ac_to_hwq[q_mapping];

        return queue;
}

static void rtw_pci_release_rsvd_page(struct rtw_pci *rtwpci,
                                      struct rtw_pci_tx_ring *ring)
{
        struct sk_buff *prev = skb_dequeue(&ring->queue);
        struct rtw_pci_tx_data *tx_data;
        dma_addr_t dma;

        if (!prev)
                return;

        tx_data = rtw_pci_get_tx_data(prev);
        dma = tx_data->dma;
        pci_unmap_single(rtwpci->pdev, dma, prev->len,
                         PCI_DMA_TODEVICE);
        dev_kfree_skb_any(prev);
}

static void rtw_pci_dma_check(struct rtw_dev *rtwdev,
                              struct rtw_pci_rx_ring *rx_ring,
                              u32 idx)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;
        struct rtw_chip_info *chip = rtwdev->chip;
        struct rtw_pci_rx_buffer_desc *buf_desc;
        u32 desc_sz = chip->rx_buf_desc_sz;
        u16 total_pkt_size;

        buf_desc = (struct rtw_pci_rx_buffer_desc *)(rx_ring->r.head +
                                                     idx * desc_sz);
        total_pkt_size = le16_to_cpu(buf_desc->total_pkt_size);

        /* rx tag mismatch, throw a warning */
        if (total_pkt_size != rtwpci->rx_tag)
                rtw_warn(rtwdev, "pci bus timeout, check dma status\n");

        rtwpci->rx_tag = (rtwpci->rx_tag + 1) % RX_TAG_MAX;
}

static void rtw_pci_tx_kick_off_queue(struct rtw_dev *rtwdev, u8 queue)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;
        struct rtw_pci_tx_ring *ring;
        u32 bd_idx;

        ring = &rtwpci->tx_rings[queue];
        bd_idx = rtw_pci_tx_queue_idx_addr[queue];

        spin_lock_bh(&rtwpci->irq_lock);
        rtw_pci_deep_ps_leave(rtwdev);
        rtw_write16(rtwdev, bd_idx, ring->r.wp & TRX_BD_IDX_MASK);
        spin_unlock_bh(&rtwpci->irq_lock);
}

static void rtw_pci_tx_kick_off(struct rtw_dev *rtwdev)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;
        u8 queue;

        for (queue = 0; queue < RTK_MAX_TX_QUEUE_NUM; queue++)
                if (test_and_clear_bit(queue, rtwpci->tx_queued))
                        rtw_pci_tx_kick_off_queue(rtwdev, queue);
}

static int rtw_pci_tx_write_data(struct rtw_dev *rtwdev,
                                 struct rtw_tx_pkt_info *pkt_info,
                                 struct sk_buff *skb, u8 queue)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;
        struct rtw_chip_info *chip = rtwdev->chip;
        struct rtw_pci_tx_ring *ring;
        struct rtw_pci_tx_data *tx_data;
        dma_addr_t dma;
        u32 tx_pkt_desc_sz = chip->tx_pkt_desc_sz;
        u32 tx_buf_desc_sz = chip->tx_buf_desc_sz;
        u32 size;
        u32 psb_len;
        u8 *pkt_desc;
        struct rtw_pci_tx_buffer_desc *buf_desc;

        ring = &rtwpci->tx_rings[queue];

        size = skb->len;

        if (queue == RTW_TX_QUEUE_BCN)
                rtw_pci_release_rsvd_page(rtwpci, ring);
        else if (!avail_desc(ring->r.wp, ring->r.rp, ring->r.len))
                return -ENOSPC;

        pkt_desc = skb_push(skb, chip->tx_pkt_desc_sz);
        memset(pkt_desc, 0, tx_pkt_desc_sz);
        pkt_info->qsel = rtw_pci_get_tx_qsel(skb, queue);
        rtw_tx_fill_tx_desc(pkt_info, skb);
        dma = pci_map_single(rtwpci->pdev, skb->data, skb->len,
                             PCI_DMA_TODEVICE);
        if (pci_dma_mapping_error(rtwpci->pdev, dma))
                return -EBUSY;

        /* after this we got dma mapped, there is no way back */
        buf_desc = get_tx_buffer_desc(ring, tx_buf_desc_sz);
        memset(buf_desc, 0, tx_buf_desc_sz);
        psb_len = (skb->len - 1) / 128 + 1;
        if (queue == RTW_TX_QUEUE_BCN)
                psb_len |= 1 << RTK_PCI_TXBD_OWN_OFFSET;

        buf_desc[0].psb_len = cpu_to_le16(psb_len);
        buf_desc[0].buf_size = cpu_to_le16(tx_pkt_desc_sz);
        buf_desc[0].dma = cpu_to_le32(dma);
        buf_desc[1].buf_size = cpu_to_le16(size);
        buf_desc[1].dma = cpu_to_le32(dma + tx_pkt_desc_sz);

        tx_data = rtw_pci_get_tx_data(skb);
        tx_data->dma = dma;
        tx_data->sn = pkt_info->sn;

        spin_lock_bh(&rtwpci->irq_lock);

        skb_queue_tail(&ring->queue, skb);

        if (queue == RTW_TX_QUEUE_BCN)
                goto out_unlock;

        /* update write-index, and kick it off later */
        set_bit(queue, rtwpci->tx_queued);
        if (++ring->r.wp >= ring->r.len)
                ring->r.wp = 0;

out_unlock:
        spin_unlock_bh(&rtwpci->irq_lock);

        return 0;
}

static int rtw_pci_write_data_rsvd_page(struct rtw_dev *rtwdev, u8 *buf,
                                        u32 size)
{
        struct sk_buff *skb;
        struct rtw_tx_pkt_info pkt_info = {0};
        u8 reg_bcn_work;
        int ret;

        skb = rtw_tx_write_data_rsvd_page_get(rtwdev, &pkt_info, buf, size);
        if (!skb)
                return -ENOMEM;

        ret = rtw_pci_tx_write_data(rtwdev, &pkt_info, skb, RTW_TX_QUEUE_BCN);
        if (ret) {
                rtw_err(rtwdev, "failed to write rsvd page data\n");
                return ret;
        }

        /* reserved pages go through beacon queue */
        reg_bcn_work = rtw_read8(rtwdev, RTK_PCI_TXBD_BCN_WORK);
        reg_bcn_work |= BIT_PCI_BCNQ_FLAG;
        rtw_write8(rtwdev, RTK_PCI_TXBD_BCN_WORK, reg_bcn_work);

        return 0;
}

static int rtw_pci_write_data_h2c(struct rtw_dev *rtwdev, u8 *buf, u32 size)
{
        struct sk_buff *skb;
        struct rtw_tx_pkt_info pkt_info = {0};
        int ret;

        skb = rtw_tx_write_data_h2c_get(rtwdev, &pkt_info, buf, size);
        if (!skb)
                return -ENOMEM;

        ret = rtw_pci_tx_write_data(rtwdev, &pkt_info, skb, RTW_TX_QUEUE_H2C);
        if (ret) {
                rtw_err(rtwdev, "failed to write h2c data\n");
                return ret;
        }

        rtw_pci_tx_kick_off_queue(rtwdev, RTW_TX_QUEUE_H2C);

        return 0;
}

static int rtw_pci_tx_write(struct rtw_dev *rtwdev,
                            struct rtw_tx_pkt_info *pkt_info,
                            struct sk_buff *skb)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;
        struct rtw_pci_tx_ring *ring;
        u8 queue = rtw_hw_queue_mapping(skb);
        int ret;

        ret = rtw_pci_tx_write_data(rtwdev, pkt_info, skb, queue);
        if (ret)
                return ret;

        ring = &rtwpci->tx_rings[queue];
        if (avail_desc(ring->r.wp, ring->r.rp, ring->r.len) < 2) {
                ieee80211_stop_queue(rtwdev->hw, skb_get_queue_mapping(skb));
                ring->queue_stopped = true;
        }

        return 0;
}

static void rtw_pci_tx_isr(struct rtw_dev *rtwdev, struct rtw_pci *rtwpci,
                           u8 hw_queue)
{
        struct ieee80211_hw *hw = rtwdev->hw;
        struct ieee80211_tx_info *info;
        struct rtw_pci_tx_ring *ring;
        struct rtw_pci_tx_data *tx_data;
        struct sk_buff *skb;
        u32 count;
        u32 bd_idx_addr;
        u32 bd_idx, cur_rp;
        u16 q_map;

        ring = &rtwpci->tx_rings[hw_queue];

        bd_idx_addr = rtw_pci_tx_queue_idx_addr[hw_queue];
        bd_idx = rtw_read32(rtwdev, bd_idx_addr);
        cur_rp = bd_idx >> 16;
        cur_rp &= TRX_BD_IDX_MASK;
        if (cur_rp >= ring->r.rp)
                count = cur_rp - ring->r.rp;
        else
                count = ring->r.len - (ring->r.rp - cur_rp);

        while (count--) {
                skb = skb_dequeue(&ring->queue);
                if (!skb) {
                        rtw_err(rtwdev, "failed to dequeue %d skb TX queue %d, BD=0x%08x, rp %d -> %d\n",
                                count, hw_queue, bd_idx, ring->r.rp, cur_rp);
                        break;
                }
                tx_data = rtw_pci_get_tx_data(skb);
                pci_unmap_single(rtwpci->pdev, tx_data->dma, skb->len,
                                 PCI_DMA_TODEVICE);

                /* just free command packets from host to card */
                if (hw_queue == RTW_TX_QUEUE_H2C) {
                        dev_kfree_skb_irq(skb);
                        continue;
                }

                if (ring->queue_stopped &&
                    avail_desc(ring->r.wp, ring->r.rp, ring->r.len) > 4) {
                        q_map = skb_get_queue_mapping(skb);
                        ieee80211_wake_queue(hw, q_map);
                        ring->queue_stopped = false;
                }

                skb_pull(skb, rtwdev->chip->tx_pkt_desc_sz);

                info = IEEE80211_SKB_CB(skb);

                /* enqueue to wait for tx report */
                if (info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS) {
                        rtw_tx_report_enqueue(rtwdev, skb, tx_data->sn);
                        continue;
                }

                /* always ACK for others, then they won't be marked as drop */
                if (info->flags & IEEE80211_TX_CTL_NO_ACK)
                        info->flags |= IEEE80211_TX_STAT_NOACK_TRANSMITTED;
                else
                        info->flags |= IEEE80211_TX_STAT_ACK;

                ieee80211_tx_info_clear_status(info);
                ieee80211_tx_status_irqsafe(hw, skb);
        }

        ring->r.rp = cur_rp;
}

static void rtw_pci_rx_isr(struct rtw_dev *rtwdev, struct rtw_pci *rtwpci,
                           u8 hw_queue)
{
        struct rtw_chip_info *chip = rtwdev->chip;
        struct rtw_pci_rx_ring *ring;
        struct rtw_rx_pkt_stat pkt_stat;
        struct ieee80211_rx_status rx_status;
        struct sk_buff *skb, *new;
        u32 cur_wp, cur_rp, tmp;
        u32 count;
        u32 pkt_offset;
        u32 pkt_desc_sz = chip->rx_pkt_desc_sz;
        u32 buf_desc_sz = chip->rx_buf_desc_sz;
        u32 new_len;
        u8 *rx_desc;
        dma_addr_t dma;

        ring = &rtwpci->rx_rings[RTW_RX_QUEUE_MPDU];

        tmp = rtw_read32(rtwdev, RTK_PCI_RXBD_IDX_MPDUQ);
        cur_wp = tmp >> 16;
        cur_wp &= TRX_BD_IDX_MASK;
        if (cur_wp >= ring->r.wp)
                count = cur_wp - ring->r.wp;
        else
                count = ring->r.len - (ring->r.wp - cur_wp);

        cur_rp = ring->r.rp;
        while (count--) {
                rtw_pci_dma_check(rtwdev, ring, cur_rp);
                skb = ring->buf[cur_rp];
                dma = *((dma_addr_t *)skb->cb);
                dma_sync_single_for_cpu(rtwdev->dev, dma, RTK_PCI_RX_BUF_SIZE,
                                        DMA_FROM_DEVICE);
                rx_desc = skb->data;
                chip->ops->query_rx_desc(rtwdev, rx_desc, &pkt_stat, &rx_status);

                /* offset from rx_desc to payload */
                pkt_offset = pkt_desc_sz + pkt_stat.drv_info_sz +
                             pkt_stat.shift;

                /* allocate a new skb for this frame,
                 * discard the frame if none available
                 */
                new_len = pkt_stat.pkt_len + pkt_offset;
                new = dev_alloc_skb(new_len);
                if (WARN_ONCE(!new, "rx routine starvation\n"))
                        goto next_rp;

                /* put the DMA data including rx_desc from phy to new skb */
                skb_put_data(new, skb->data, new_len);

                if (pkt_stat.is_c2h) {
                        rtw_fw_c2h_cmd_rx_irqsafe(rtwdev, pkt_offset, new);
                } else {
                        /* remove rx_desc */
                        skb_pull(new, pkt_offset);

                        rtw_rx_stats(rtwdev, pkt_stat.vif, new);
                        memcpy(new->cb, &rx_status, sizeof(rx_status));
                        ieee80211_rx_irqsafe(rtwdev->hw, new);
                }

next_rp:
                /* new skb delivered to mac80211, re-enable original skb DMA */
                rtw_pci_sync_rx_desc_device(rtwdev, dma, ring, cur_rp,
                                            buf_desc_sz);

                /* host read next element in ring */
                if (++cur_rp >= ring->r.len)
                        cur_rp = 0;
        }

        ring->r.rp = cur_rp;
        ring->r.wp = cur_wp;
        rtw_write16(rtwdev, RTK_PCI_RXBD_IDX_MPDUQ, ring->r.rp);
}

static void rtw_pci_irq_recognized(struct rtw_dev *rtwdev,
                                   struct rtw_pci *rtwpci, u32 *irq_status)
{
        unsigned long flags;

        spin_lock_irqsave(&rtwpci->hwirq_lock, flags);

        irq_status[0] = rtw_read32(rtwdev, RTK_PCI_HISR0);
        irq_status[1] = rtw_read32(rtwdev, RTK_PCI_HISR1);
        if (rtw_chip_wcpu_11ac(rtwdev))
                irq_status[3] = rtw_read32(rtwdev, RTK_PCI_HISR3);
        else
                irq_status[3] = 0;
        irq_status[0] &= rtwpci->irq_mask[0];
        irq_status[1] &= rtwpci->irq_mask[1];
        irq_status[3] &= rtwpci->irq_mask[3];
        rtw_write32(rtwdev, RTK_PCI_HISR0, irq_status[0]);
        rtw_write32(rtwdev, RTK_PCI_HISR1, irq_status[1]);
        if (rtw_chip_wcpu_11ac(rtwdev))
                rtw_write32(rtwdev, RTK_PCI_HISR3, irq_status[3]);

        spin_unlock_irqrestore(&rtwpci->hwirq_lock, flags);
}

static irqreturn_t rtw_pci_interrupt_handler(int irq, void *dev)
{
        struct rtw_dev *rtwdev = dev;
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;

        /* disable RTW PCI interrupt to avoid more interrupts before the end of
         * thread function
         *
         * disable HIMR here to also avoid new HISR flag being raised before
         * the HISRs have been Write-1-cleared for MSI. If not all of the HISRs
         * are cleared, the edge-triggered interrupt will not be generated when
         * a new HISR flag is set.
         */
        rtw_pci_disable_interrupt(rtwdev, rtwpci);

        return IRQ_WAKE_THREAD;
}

static irqreturn_t rtw_pci_interrupt_threadfn(int irq, void *dev)
{
        struct rtw_dev *rtwdev = dev;
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;
        u32 irq_status[4];

        spin_lock_bh(&rtwpci->irq_lock);
        rtw_pci_irq_recognized(rtwdev, rtwpci, irq_status);

        if (irq_status[0] & IMR_MGNTDOK)
                rtw_pci_tx_isr(rtwdev, rtwpci, RTW_TX_QUEUE_MGMT);
        if (irq_status[0] & IMR_HIGHDOK)
                rtw_pci_tx_isr(rtwdev, rtwpci, RTW_TX_QUEUE_HI0);
        if (irq_status[0] & IMR_BEDOK)
                rtw_pci_tx_isr(rtwdev, rtwpci, RTW_TX_QUEUE_BE);
        if (irq_status[0] & IMR_BKDOK)
                rtw_pci_tx_isr(rtwdev, rtwpci, RTW_TX_QUEUE_BK);
        if (irq_status[0] & IMR_VODOK)
                rtw_pci_tx_isr(rtwdev, rtwpci, RTW_TX_QUEUE_VO);
        if (irq_status[0] & IMR_VIDOK)
                rtw_pci_tx_isr(rtwdev, rtwpci, RTW_TX_QUEUE_VI);
        if (irq_status[3] & IMR_H2CDOK)
                rtw_pci_tx_isr(rtwdev, rtwpci, RTW_TX_QUEUE_H2C);
        if (irq_status[0] & IMR_ROK)
                rtw_pci_rx_isr(rtwdev, rtwpci, RTW_RX_QUEUE_MPDU);

        /* all of the jobs for this interrupt have been done */
        rtw_pci_enable_interrupt(rtwdev, rtwpci);
        spin_unlock_bh(&rtwpci->irq_lock);

        return IRQ_HANDLED;
}

static int rtw_pci_io_mapping(struct rtw_dev *rtwdev,
                              struct pci_dev *pdev)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;
        unsigned long len;
        u8 bar_id = 2;
        int ret;

        ret = pci_request_regions(pdev, KBUILD_MODNAME);
        if (ret) {
                rtw_err(rtwdev, "failed to request pci regions\n");
                return ret;
        }

        len = pci_resource_len(pdev, bar_id);
        rtwpci->mmap = pci_iomap(pdev, bar_id, len);
        if (!rtwpci->mmap) {
                pci_release_regions(pdev);
                rtw_err(rtwdev, "failed to map pci memory\n");
                return -ENOMEM;
        }

        return 0;
}

static void rtw_pci_io_unmapping(struct rtw_dev *rtwdev,
                                 struct pci_dev *pdev)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;

        if (rtwpci->mmap) {
                pci_iounmap(pdev, rtwpci->mmap);
                pci_release_regions(pdev);
        }
}

static void rtw_dbi_write8(struct rtw_dev *rtwdev, u16 addr, u8 data)
{
        u16 write_addr;
        u16 remainder = addr & ~(BITS_DBI_WREN | BITS_DBI_ADDR_MASK);
        u8 flag;
        u8 cnt;

        write_addr = addr & BITS_DBI_ADDR_MASK;
        write_addr |= u16_encode_bits(BIT(remainder), BITS_DBI_WREN);
        rtw_write8(rtwdev, REG_DBI_WDATA_V1 + remainder, data);
        rtw_write16(rtwdev, REG_DBI_FLAG_V1, write_addr);
        rtw_write8(rtwdev, REG_DBI_FLAG_V1 + 2, BIT_DBI_WFLAG >> 16);

        for (cnt = 0; cnt < RTW_PCI_WR_RETRY_CNT; cnt++) {
                flag = rtw_read8(rtwdev, REG_DBI_FLAG_V1 + 2);
                if (flag == 0)
                        return;

                udelay(10);
        }

        WARN(flag, "failed to write to DBI register, addr=0x%04x\n", addr);
}

static int rtw_dbi_read8(struct rtw_dev *rtwdev, u16 addr, u8 *value)
{
        u16 read_addr = addr & BITS_DBI_ADDR_MASK;
        u8 flag;
        u8 cnt;

        rtw_write16(rtwdev, REG_DBI_FLAG_V1, read_addr);
        rtw_write8(rtwdev, REG_DBI_FLAG_V1 + 2, BIT_DBI_RFLAG >> 16);

        for (cnt = 0; cnt < RTW_PCI_WR_RETRY_CNT; cnt++) {
                flag = rtw_read8(rtwdev, REG_DBI_FLAG_V1 + 2);
                if (flag == 0) {
                        read_addr = REG_DBI_RDATA_V1 + (addr & 3);
                        *value = rtw_read8(rtwdev, read_addr);
                        return 0;
                }

                udelay(10);
        }

        WARN(1, "failed to read DBI register, addr=0x%04x\n", addr);
        return -EIO;
}

static void rtw_mdio_write(struct rtw_dev *rtwdev, u8 addr, u16 data, bool g1)
{
        u8 page;
        u8 wflag;
        u8 cnt;

        rtw_write16(rtwdev, REG_MDIO_V1, data);

        page = addr < RTW_PCI_MDIO_PG_SZ ? 0 : 1;
        page += g1 ? RTW_PCI_MDIO_PG_OFFS_G1 : RTW_PCI_MDIO_PG_OFFS_G2;
        rtw_write8(rtwdev, REG_PCIE_MIX_CFG, addr & BITS_MDIO_ADDR_MASK);
        rtw_write8(rtwdev, REG_PCIE_MIX_CFG + 3, page);
        rtw_write32_mask(rtwdev, REG_PCIE_MIX_CFG, BIT_MDIO_WFLAG_V1, 1);

        for (cnt = 0; cnt < RTW_PCI_WR_RETRY_CNT; cnt++) {
                wflag = rtw_read32_mask(rtwdev, REG_PCIE_MIX_CFG,
                                        BIT_MDIO_WFLAG_V1);
                if (wflag == 0)
                        return;

                udelay(10);
        }

        WARN(wflag, "failed to write to MDIO register, addr=0x%02x\n", addr);
}

static void rtw_pci_clkreq_set(struct rtw_dev *rtwdev, bool enable)
{
        u8 value;
        int ret;

        if (rtw_pci_disable_aspm)
                return;

        ret = rtw_dbi_read8(rtwdev, RTK_PCIE_LINK_CFG, &value);
        if (ret) {
                rtw_err(rtwdev, "failed to read CLKREQ_L1, ret=%d", ret);
                return;
        }

        if (enable)
                value |= BIT_CLKREQ_SW_EN;
        else
                value &= ~BIT_CLKREQ_SW_EN;

        rtw_dbi_write8(rtwdev, RTK_PCIE_LINK_CFG, value);
}

static void rtw_pci_aspm_set(struct rtw_dev *rtwdev, bool enable)
{
        u8 value;
        int ret;

        if (rtw_pci_disable_aspm)
                return;

        ret = rtw_dbi_read8(rtwdev, RTK_PCIE_LINK_CFG, &value);
        if (ret) {
                rtw_err(rtwdev, "failed to read ASPM, ret=%d", ret);
                return;
        }

        if (enable)
                value |= BIT_L1_SW_EN;
        else
                value &= ~BIT_L1_SW_EN;

        rtw_dbi_write8(rtwdev, RTK_PCIE_LINK_CFG, value);
}

static void rtw_pci_link_ps(struct rtw_dev *rtwdev, bool enter)
{
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;

        /* Like CLKREQ, ASPM is also implemented by two HW modules, and can
         * only be enabled when host supports it.
         *
         * And ASPM mechanism should be enabled when driver/firmware enters
         * power save mode, without having heavy traffic. Because we've
         * experienced some inter-operability issues that the link tends
         * to enter L1 state on the fly even when driver is having high
         * throughput. This is probably because the ASPM behavior slightly
         * varies from different SOC.
         */
        if (rtwpci->link_ctrl & PCI_EXP_LNKCTL_ASPM_L1)
                rtw_pci_aspm_set(rtwdev, enter);
}

static void rtw_pci_link_cfg(struct rtw_dev *rtwdev)
{
        struct rtw_chip_info *chip = rtwdev->chip;
        struct rtw_pci *rtwpci = (struct rtw_pci *)rtwdev->priv;
        struct pci_dev *pdev = rtwpci->pdev;
        u16 link_ctrl;
        int ret;

        /* RTL8822CE has enabled REFCLK auto calibration, it does not need
         * to add clock delay to cover the REFCLK timing gap.
         */
        if (chip->id == RTW_CHIP_TYPE_8822C)
                rtw_dbi_write8(rtwdev, RTK_PCIE_CLKDLY_CTRL, 0);

        /* Though there is standard PCIE configuration space to set the
         * link control register, but by Realtek's design, driver should
         * check if host supports CLKREQ/ASPM to enable the HW module.
         *
         * These functions are implemented by two HW modules associated,
         * one is responsible to access PCIE configuration space to
         * follow the host settings, and another is in charge of doing
         * CLKREQ/ASPM mechanisms, it is default disabled. Because sometimes
         * the host does not support it, and due to some reasons or wrong
         * settings (ex. CLKREQ# not Bi-Direction), it could lead to device
         * loss if HW misbehaves on the link.
         *
         * Hence it's designed that driver should first check the PCIE
         * configuration space is sync'ed and enabled, then driver can turn
         * on the other module that is actually working on the mechanism.
         */
        ret = pcie_capability_read_word(pdev, PCI_EXP_LNKCTL, &link_ctrl);
        if (ret) {
                rtw_err(rtwdev, "failed to read PCI cap, ret=%d\n", ret);
                return;
        }

        if (link_ctrl & PCI_EXP_LNKCTL_CLKREQ_EN)
                rtw_pci_clkreq_set(rtwdev, true);

        rtwpci->link_ctrl = link_ctrl;
}

static void rtw_pci_interface_cfg(struct rtw_dev *rtwdev)
{
        struct rtw_chip_info *chip = rtwdev->chip;

        switch (chip->id) {
        case RTW_CHIP_TYPE_8822C:
                if (rtwdev->hal.cut_version >= RTW_CHIP_VER_CUT_D)
                        rtw_write32_mask(rtwdev, REG_HCI_MIX_CFG,
                                         BIT_PCIE_EMAC_PDN_AUX_TO_FAST_CLK, 1);
                break;
        default:
                break;
        }
}

static void rtw_pci_phy_cfg(struct rtw_dev *rtwdev)
{
        struct rtw_chip_info *chip = rtwdev->chip;
        const struct rtw_intf_phy_para *para;
        u16 cut;
        u16 value;
        u16 offset;
        int i;

        cut = BIT(0) << rtwdev->hal.cut_version;

        for (i = 0; i < chip->intf_table->n_gen1_para; i++) {
                para = &chip->intf_table->gen1_para[i];
                if (!(para->cut_mask & cut))
                        continue;
                if (para->offset == 0xffff)
                        break;
                offset = para->offset;
                value = para->value;
                if (para->ip_sel == RTW_IP_SEL_PHY)
                        rtw_mdio_write(rtwdev, offset, value, true);
                else
                        rtw_dbi_write8(rtwdev, offset, value);
        }

        for (i = 0; i < chip->intf_table->n_gen2_para; i++) {
                para = &chip->intf_table->gen2_para[i];
                if (!(para->cut_mask & cut))
                        continue;
                if (para->offset == 0xffff)
                        break;
                offset = para->offset;
                value = para->value;
                if (para->ip_sel == RTW_IP_SEL_PHY)
                        rtw_mdio_write(rtwdev, offset, value, false);
                else
                        rtw_dbi_write8(rtwdev, offset, value);
        }

        rtw_pci_link_cfg(rtwdev);
}

static int __maybe_unused rtw_pci_suspend(struct device *dev)
{
        return 0;
}

static int __maybe_unused rtw_pci_resume(struct device *dev)
{
        return 0;
}

SIMPLE_DEV_PM_OPS(rtw_pm_ops, rtw_pci_suspend, rtw_pci_resume);
EXPORT_SYMBOL(rtw_pm_ops);

static int rtw_pci_claim(struct rtw_dev *rtwdev, struct pci_dev *pdev)
{
        int ret;

        ret = pci_enable_device(pdev);
        if (ret) {
                rtw_err(rtwdev, "failed to enable pci device\n");
                return ret;
        }

        pci_set_master(pdev);
        pci_set_drvdata(pdev, rtwdev->hw);
        SET_IEEE80211_DEV(rtwdev->hw, &pdev->dev);

        return 0;
}

static void rtw_pci_declaim(struct rtw_dev *rtwdev, struct pci_dev *pdev)
{
        pci_clear_master(pdev);
        pci_disable_device(pdev);
}

static int rtw_pci_setup_resource(struct rtw_dev *rtwdev, struct pci_dev *pdev)
{
        struct rtw_pci *rtwpci;
        int ret;

        rtwpci = (struct rtw_pci *)rtwdev->priv;
        rtwpci->pdev = pdev;

        /* after this driver can access to hw registers */
        ret = rtw_pci_io_mapping(rtwdev, pdev);
        if (ret) {
                rtw_err(rtwdev, "failed to request pci io region\n");
                goto err_out;
        }

        ret = rtw_pci_init(rtwdev);
        if (ret) {
                rtw_err(rtwdev, "failed to allocate pci resources\n");
                goto err_io_unmap;
        }

        return 0;

err_io_unmap:
        rtw_pci_io_unmapping(rtwdev, pdev);

err_out:
        return ret;
}

static void rtw_pci_destroy(struct rtw_dev *rtwdev, struct pci_dev *pdev)
{
        rtw_pci_deinit(rtwdev);
        rtw_pci_io_unmapping(rtwdev, pdev);
}

static struct rtw_hci_ops rtw_pci_ops = {
        .tx_write = rtw_pci_tx_write,
        .tx_kick_off = rtw_pci_tx_kick_off,
        .setup = rtw_pci_setup,
        .start = rtw_pci_start,
        .stop = rtw_pci_stop,
        .deep_ps = rtw_pci_deep_ps,
        .link_ps = rtw_pci_link_ps,
        .interface_cfg = rtw_pci_interface_cfg,

        .read8 = rtw_pci_read8,
        .read16 = rtw_pci_read16,
        .read32 = rtw_pci_read32,
        .write8 = rtw_pci_write8,
        .write16 = rtw_pci_write16,
        .write32 = rtw_pci_write32,
        .write_data_rsvd_page = rtw_pci_write_data_rsvd_page,
        .write_data_h2c = rtw_pci_write_data_h2c,
};

static int rtw_pci_request_irq(struct rtw_dev *rtwdev, struct pci_dev *pdev)
{
        unsigned int flags = PCI_IRQ_LEGACY;
        int ret;

        if (!rtw_disable_msi)
                flags |= PCI_IRQ_MSI;

        ret = pci_alloc_irq_vectors(pdev, 1, 1, flags);
        if (ret < 0) {
                rtw_err(rtwdev, "failed to alloc PCI irq vectors\n");
                return ret;
        }

        ret = devm_request_threaded_irq(rtwdev->dev, pdev->irq,
                                        rtw_pci_interrupt_handler,
                                        rtw_pci_interrupt_threadfn,
                                        IRQF_SHARED, KBUILD_MODNAME, rtwdev);
        if (ret) {
                rtw_err(rtwdev, "failed to request irq %d\n", ret);
                pci_free_irq_vectors(pdev);
        }

        return ret;
}

static void rtw_pci_free_irq(struct rtw_dev *rtwdev, struct pci_dev *pdev)
{
        devm_free_irq(rtwdev->dev, pdev->irq, rtwdev);
        pci_free_irq_vectors(pdev);
}

int rtw_pci_probe(struct pci_dev *pdev,
                  const struct pci_device_id *id)
{
        struct ieee80211_hw *hw;
        struct rtw_dev *rtwdev;
        int drv_data_size;
        int ret;

        drv_data_size = sizeof(struct rtw_dev) + sizeof(struct rtw_pci);
        hw = ieee80211_alloc_hw(drv_data_size, &rtw_ops);
        if (!hw) {
                dev_err(&pdev->dev, "failed to allocate hw\n");
                return -ENOMEM;
        }

        rtwdev = hw->priv;
        rtwdev->hw = hw;
        rtwdev->dev = &pdev->dev;
        rtwdev->chip = (struct rtw_chip_info *)id->driver_data;
        rtwdev->hci.ops = &rtw_pci_ops;
        rtwdev->hci.type = RTW_HCI_TYPE_PCIE;

        ret = rtw_core_init(rtwdev);
        if (ret)
                goto err_release_hw;

        rtw_dbg(rtwdev, RTW_DBG_PCI,
                "rtw88 pci probe: vendor=0x%4.04X device=0x%4.04X rev=%d\n",
                pdev->vendor, pdev->device, pdev->revision);

        ret = rtw_pci_claim(rtwdev, pdev);
        if (ret) {
                rtw_err(rtwdev, "failed to claim pci device\n");
                goto err_deinit_core;
        }

        ret = rtw_pci_setup_resource(rtwdev, pdev);
        if (ret) {
                rtw_err(rtwdev, "failed to setup pci resources\n");
                goto err_pci_declaim;
        }

        ret = rtw_chip_info_setup(rtwdev);
        if (ret) {
                rtw_err(rtwdev, "failed to setup chip information\n");
                goto err_destroy_pci;
        }

        rtw_pci_phy_cfg(rtwdev);

        ret = rtw_register_hw(rtwdev, hw);
        if (ret) {
                rtw_err(rtwdev, "failed to register hw\n");
                goto err_destroy_pci;
        }

        ret = rtw_pci_request_irq(rtwdev, pdev);
        if (ret) {
                ieee80211_unregister_hw(hw);
                goto err_destroy_pci;
        }

        return 0;

err_destroy_pci:
        rtw_pci_destroy(rtwdev, pdev);

err_pci_declaim:
        rtw_pci_declaim(rtwdev, pdev);

err_deinit_core:
        rtw_core_deinit(rtwdev);

err_release_hw:
        ieee80211_free_hw(hw);

        return ret;
}
EXPORT_SYMBOL(rtw_pci_probe);

void rtw_pci_remove(struct pci_dev *pdev)
{
        struct ieee80211_hw *hw = pci_get_drvdata(pdev);
        struct rtw_dev *rtwdev;
        struct rtw_pci *rtwpci;

        if (!hw)
                return;

        rtwdev = hw->priv;
        rtwpci = (struct rtw_pci *)rtwdev->priv;

        rtw_unregister_hw(rtwdev, hw);
        rtw_pci_disable_interrupt(rtwdev, rtwpci);
        rtw_pci_destroy(rtwdev, pdev);
        rtw_pci_declaim(rtwdev, pdev);
        rtw_pci_free_irq(rtwdev, pdev);
        rtw_core_deinit(rtwdev);
        ieee80211_free_hw(hw);
}
EXPORT_SYMBOL(rtw_pci_remove);

void rtw_pci_shutdown(struct pci_dev *pdev)
{
        struct ieee80211_hw *hw = pci_get_drvdata(pdev);
        struct rtw_dev *rtwdev;
        struct rtw_chip_info *chip;

        if (!hw)
                return;

        rtwdev = hw->priv;
        chip = rtwdev->chip;

        if (chip->ops->shutdown)
                chip->ops->shutdown(rtwdev);
}
EXPORT_SYMBOL(rtw_pci_shutdown);

MODULE_AUTHOR("Realtek Corporation");
MODULE_DESCRIPTION("Realtek 802.11ac wireless PCI driver");
MODULE_LICENSE("Dual BSD/GPL");