Re: [PATCH v10 1/6] net: wwan: t9xx: Add PCIe core
From: Loic Poulain
Date: Wed Oct 14 2026 - 09:04:05 EST
On Wed, Oct 14, 2026 at 4:52 AM Jack Wu via B4 Relay
<devnull+jackbb_wu.compal.com@xxxxxxxxxx> wrote:
>
> From: Jack Wu <jackbb_wu@xxxxxxxxxx>
>
> Registers the T900 device driver with the kernel. Set up all
> the fundamental configurations for the device: PCIe layer,
> Modem Host Cross Core Interface (MHCCIF), modem common control
> operations, build infrastructure and MAINTAINERS entry.
> Besides the T900 itself (14c3:0900) the driver binds its
> HP-branded variant, the HP RMM-G4 (03f0:01ca); both IDs are
> exported via MODULE_DEVICE_TABLE for module autoloading.
>
> * PCIe layer code implements driver probe and removal, MSI-X
> interrupt initialization and de-initialization, and the way
> of resetting the device.
> * MHCCIF provides the interrupt channels used for the boot
> handshake and for the host-to-device reset doorbell.
> * Modem common control operations provide the basic read/write
> functions of the device's hardware registers,
> mask/unmask/get/clear functions of the device's interrupt
> registers and inquiry functions of the device's status.
> * Add MAINTAINERS entry for the MediaTek T9XX 5G WWAN modem
> device driver.
>
> Removal resets the modem, because the next driver load has to
> redo the device handshake and status sync and cannot do that
> against firmware left running by the previous load.
> mtk_pci_remove() evaluates MRST._RST on the device's own ACPI
> node: that is a platform-level reset and does not depend on the
> firmware's state. Where the platform has no MRST._RST, removal
> falls back to the MHCCIF DEV_EVT_H2D_DEVICE_RESET doorbell if
> the link is still up. The doorbell is a request to the
> firmware, so it is best effort and cannot recover firmware that
> has stopped responding - the case the reset exists for. Probe
> therefore does not require MRST._RST; without it the driver
> still binds and only removal is degraded.
>
> Signed-off-by: Jack Wu <jackbb_wu@xxxxxxxxxx>
> ---
> MAINTAINERS | 11 +
> drivers/net/wwan/Kconfig | 11 +
> drivers/net/wwan/Makefile | 1 +
> drivers/net/wwan/t9xx/Makefile | 9 +
> drivers/net/wwan/t9xx/mtk_dev.h | 42 ++
> drivers/net/wwan/t9xx/pcie/mtk_pci.c | 1042 ++++++++++++++++++++++++++++++
> drivers/net/wwan/t9xx/pcie/mtk_pci.h | 140 ++++
> drivers/net/wwan/t9xx/pcie/mtk_pci_reg.h | 34 +
> 8 files changed, 1290 insertions(+)
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 461a3eed6129..8f13ef7440ce 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -16494,6 +16494,17 @@ L: netdev@xxxxxxxxxxxxxxx
> S: Supported
> F: drivers/net/wwan/t7xx/
>
> +MEDIATEK T9XX 5G WWAN MODEM DRIVER
> +M: Jack Wu <jackbb_wu@xxxxxxxxxx>
> +M: Robert Yu <robert_yu@xxxxxxxxxx>
> +M: Jeff Chang <Jeff_Chang@xxxxxxxxxx>
> +R: Wen-Zhi Huang <wen-zhi.huang@xxxxxxxxxxxx>
> +R: Shi-Wei Yeh <shi-wei.yeh@xxxxxxxxxxxx>
> +R: Minano Tseng <Minano.tseng@xxxxxxxxxxxx>
> +L: netdev@xxxxxxxxxxxxxxx
> +S: Supported
> +F: drivers/net/wwan/t9xx/
> +
> MEDIATEK USB3 DRD IP DRIVER
> M: Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx>
> L: linux-usb@xxxxxxxxxxxxxxx
> diff --git a/drivers/net/wwan/Kconfig b/drivers/net/wwan/Kconfig
> index 88df55d78d90..f510cc8ab4e4 100644
> --- a/drivers/net/wwan/Kconfig
> +++ b/drivers/net/wwan/Kconfig
> @@ -121,6 +121,17 @@ config MTK_T7XX
>
> If unsure, say N.
>
> +config MTK_T9XX
> + tristate "MediaTek PCIe 5G WWAN modem T9xx device"
> + depends on PCI_MSI && ACPI
> + help
> + Enables MediaTek PCIe based 5G WWAN modem (T9xx series) device.
> +
> + To compile this driver as a module, choose M here: the module will be
> + called mtk_t9xx.
> +
> + If unsure, say N.
> +
> endif # WWAN
>
> endmenu
> diff --git a/drivers/net/wwan/Makefile b/drivers/net/wwan/Makefile
> index 3960c0ae2445..7361eef4c472 100644
> --- a/drivers/net/wwan/Makefile
> +++ b/drivers/net/wwan/Makefile
> @@ -14,3 +14,4 @@ obj-$(CONFIG_QCOM_BAM_DMUX) += qcom_bam_dmux.o
> obj-$(CONFIG_RPMSG_WWAN_CTRL) += rpmsg_wwan_ctrl.o
> obj-$(CONFIG_IOSM) += iosm/
> obj-$(CONFIG_MTK_T7XX) += t7xx/
> +obj-$(CONFIG_MTK_T9XX) += t9xx/
> diff --git a/drivers/net/wwan/t9xx/Makefile b/drivers/net/wwan/t9xx/Makefile
> new file mode 100644
> index 000000000000..bd6063c85c2b
> --- /dev/null
> +++ b/drivers/net/wwan/t9xx/Makefile
> @@ -0,0 +1,9 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +
> +ccflags-y += -I$(src)/pcie
> +ccflags-y += -I$(src)
> +
> +obj-$(CONFIG_MTK_T9XX) += mtk_t9xx.o
> +
> +mtk_t9xx-y := \
> + pcie/mtk_pci.o
> diff --git a/drivers/net/wwan/t9xx/mtk_dev.h b/drivers/net/wwan/t9xx/mtk_dev.h
> new file mode 100644
> index 000000000000..329e5e6695df
> --- /dev/null
> +++ b/drivers/net/wwan/t9xx/mtk_dev.h
> @@ -0,0 +1,42 @@
> +/* SPDX-License-Identifier: GPL-2.0-only
> + *
> + * Copyright (c) 2022, MediaTek Inc.
> + */
> +
> +#ifndef __MTK_DEV_H__
> +#define __MTK_DEV_H__
> +
> +#include <linux/dma-mapping.h>
> +#include <linux/dmapool.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/sched.h>
> +#include <linux/slab.h>
> +#include <linux/spinlock.h>
Looks like a lot of headers for such a small header file. Could you
trim the unnecessary includes? For example, spinlock.h doesn't appear
to be used.
> +
> +#define MTK_DEV_STR_LEN 16
> +
> +enum mtk_user_id {
> + MTK_USER_CTRL,
> + MTK_USER_MAX
> +};
> +
> +enum mtk_dev_evt_h2d {
> + DEV_EVT_H2D_DEVICE_RESET = BIT(2),
> +};
> +
> +enum mtk_dev_evt_d2h {
> + DEV_EVT_D2H_BOOT_FLOW_SYNC = BIT(4),
> + DEV_EVT_D2H_ASYNC_HS_NOTIFY_SAP = BIT(5),
> + DEV_EVT_D2H_ASYNC_HS_NOTIFY_MD = BIT(6),
> +};
> +
> +/* mtk_md_dev defines the structure of MTK modem device */
> +struct mtk_md_dev {
> + struct device *dev;
> + void *hw_priv;
> + u32 hw_ver;
> + char dev_str[MTK_DEV_STR_LEN];
> +};
> +
> +#endif /* __MTK_DEV_H__ */
> diff --git a/drivers/net/wwan/t9xx/pcie/mtk_pci.c b/drivers/net/wwan/t9xx/pcie/mtk_pci.c
> new file mode 100644
> index 000000000000..a3bd1caf470b
> --- /dev/null
> +++ b/drivers/net/wwan/t9xx/pcie/mtk_pci.c
> @@ -0,0 +1,1042 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (c) 2022, MediaTek Inc.
> + */
> +
> +#include <linux/acpi.h>
> +#include <linux/aer.h>
> +#include <linux/bitfield.h>
> +#include <linux/delay.h>
> +#include <linux/device.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +
> +#include "mtk_dev.h"
> +#include "mtk_pci.h"
> +#include "mtk_pci_reg.h"
> +
> +#define MTK_MHCCIF_RC_BASE_ADDR 0x1000A000
> +
> +#define MTK_MHCCIF_RESET_DELAY_MS 2000
> +
> +static const int mtk_pci_irq_tbl[MTK_IRQ_SRC_MAX] = {
> + [MTK_IRQ_SRC_MHCCIF] = 28,
> + [MTK_IRQ_SRC_CLDMA0] = 27,
> + [MTK_IRQ_SRC_CLDMA1] = 26,
> +};
> +
> +#define MTK_PCI_TRANSPARENT_ATR_SIZE (0x3F)
> +#define MTK_PCI_MINIMUM_ATR_SIZE (0x1000)
> +#define ATR_SIZE_LO32_MASK GENMASK_ULL(31, 0)
> +#define ATR_SIZE_HI32_MASK GENMASK_ULL(63, 32)
> +#define ATR_SIZE_BIAS_FROM_LO32 2
> +#define ATR_ADDR_ALIGN_MASK 0xFFFFF000
> +#define ATR_EN BIT(0)
> +#define ATR_PARAM_OFFSET 16
> +#define SET_HW_BITS(dest, chs, mhccif, dev) \
> + ({ \
> + if ((chs) & (dev)) \
> + (dest) |= FIELD_PREP(mhccif, 1); \
> + })
A static inline helper would be cleaner.
> +
> +struct mtk_mhccif_cb {
> + struct list_head entry;
> + int (*evt_cb)(u32 status, void *data);
> + void *data;
> + u32 chs;
> +};
> +
> +/**
> + * mtk_pci_setup_atr() - Configure a PCIe address translation rule
> + * @mdev: MTK MD device
> + * @cfg: ATR configuration parameters
> + *
> + * Return: 0 on success, negative error code on failure.
> + */
> +int mtk_pci_setup_atr(struct mtk_md_dev *mdev, struct mtk_atr_cfg *cfg)
> +{
> + struct mtk_pci_priv *priv = mdev->hw_priv;
> + u32 addr, val, size_h, size_l;
> + int atr_size, pos, offset;
> +
> + if (cfg->transparent) {
> + /* No address conversion is performed */
> + atr_size = MTK_PCI_TRANSPARENT_ATR_SIZE;
> + } else {
> + if (cfg->size < MTK_PCI_MINIMUM_ATR_SIZE)
> + cfg->size = MTK_PCI_MINIMUM_ATR_SIZE;
> +
> + if (cfg->src_addr & (cfg->size - 1)) {
> + dev_err(mdev->dev, "Invalid atr src addr is not aligned to size\n");
> + return -EFAULT;
> + }
> +
> + if (cfg->trsl_addr & (cfg->size - 1)) {
> + dev_err(mdev->dev,
> + "Invalid atr trsl addr is not aligned to size, %llx, %llx\n",
> + cfg->trsl_addr, cfg->size - 1);
> + return -EFAULT;
> + }
> +
> + size_l = FIELD_GET(ATR_SIZE_LO32_MASK, cfg->size);
> + size_h = FIELD_GET(ATR_SIZE_HI32_MASK, cfg->size);
> + pos = ffs(size_l);
> + if (pos) {
> + atr_size = pos - ATR_SIZE_BIAS_FROM_LO32;
> + } else {
> + pos = ffs(size_h);
> + atr_size = pos + 32 - ATR_SIZE_BIAS_FROM_LO32;
> + }
> + }
> +
> + /* Calculate table offset */
> + offset = ATR_PORT_OFFSET * cfg->port + ATR_TABLE_OFFSET * cfg->table;
> +
> + addr = REG_ATR_PCIE_WIN0_T0_SRC_ADDR_MSB + offset;
> + val = (u32)(cfg->src_addr >> 32);
> + mtk_pci_mac_write32(priv, addr, val);
> +
> + addr = REG_ATR_PCIE_WIN0_T0_TRSL_ADDR_MSB + offset;
> + val = (u32)(cfg->trsl_addr >> 32);
> + mtk_pci_mac_write32(priv, addr, val);
> +
> + addr = REG_ATR_PCIE_WIN0_T0_TRSL_ADDR_LSB + offset;
> + val = (u32)(cfg->trsl_addr & ATR_ADDR_ALIGN_MASK);
> + mtk_pci_mac_write32(priv, addr, val);
> +
> + /* TRSL_PARAM */
> + addr = REG_ATR_PCIE_WIN0_T0_TRSL_PARAM + offset;
> + val = (cfg->trsl_param << ATR_PARAM_OFFSET) | cfg->trsl_id;
> + mtk_pci_mac_write32(priv, addr, val);
> +
> + /* Enable ATR last, after translation target is fully programmed */
> + addr = REG_ATR_PCIE_WIN0_T0_SRC_ADDR_LSB + offset;
> + val = (u32)(cfg->src_addr & ATR_ADDR_ALIGN_MASK) | (atr_size << 1) | ATR_EN;
> + mtk_pci_mac_write32(priv, addr, val);
> +
> + /* Ensure ATR is set */
> + mtk_pci_mac_read32(priv, addr);
> +
> + return 0;
> +}
> +
> +/**
> + * mtk_pci_atr_disable() - Disable all PCIe address translation rules
> + * @priv: MTK PCI private data
> + */
> +void mtk_pci_atr_disable(struct mtk_pci_priv *priv)
> +{
> + int port, tbl, offset;
> + u32 val;
> +
> + /* Disable all ATR table for all ports */
> + for (port = ATR_SRC_PCI_WIN0; port <= ATR_SRC_AXIS_3; port++)
> + for (tbl = 0; tbl < ATR_TABLE_NUM_PER_ATR; tbl++) {
> + /* Calculate table offset */
> + offset = ATR_PORT_OFFSET * port + ATR_TABLE_OFFSET * tbl;
> + val = mtk_pci_mac_read32(priv, REG_ATR_PCIE_WIN0_T0_SRC_ADDR_LSB + offset);
> + val = val & (~BIT(0));
> + /* Disable table by SRC_ADDR_L */
> + mtk_pci_mac_write32(priv, REG_ATR_PCIE_WIN0_T0_SRC_ADDR_LSB + offset, val);
> + }
> +}
> +
> +/**
> + * mtk_pci_get_dev_state() - Read the device state from the modem
> + * @mdev: MTK MD device
> + *
> + * Return: Device state value.
> + */
> +u32 mtk_pci_get_dev_state(struct mtk_md_dev *mdev)
> +{
> + return mtk_pci_mac_read32(mdev->hw_priv, REG_PCIE_DEBUG_DUMMY_7);
> +}
> +
> +/**
> + * mtk_pci_ack_dev_state() - Acknowledge the device state to the modem
> + * @mdev: MTK MD device
> + * @state: State value to acknowledge
> + */
> +void mtk_pci_ack_dev_state(struct mtk_md_dev *mdev, u32 state)
> +{
> + mtk_pci_mac_write32(mdev->hw_priv, REG_PCIE_DEBUG_DUMMY_7, state);
> +}
> +
> +/**
> + * mtk_pci_get_irq_id() - Map an IRQ source to its hardware IRQ ID
> + * @mdev: MTK MD device
> + * @irq_src: IRQ source enum
> + *
> + * Return: IRQ ID on success, -EINVAL on failure.
> + */
> +int mtk_pci_get_irq_id(struct mtk_md_dev *mdev, enum mtk_irq_src irq_src)
> +{
> + int irq_id = -EINVAL;
> +
> + if (irq_src > MTK_IRQ_SRC_MIN && irq_src < MTK_IRQ_SRC_MAX) {
> + irq_id = mtk_pci_irq_tbl[irq_src];
> + if (irq_id < 0 || irq_id >= MTK_IRQ_CNT_MAX)
> + irq_id = -EINVAL;
> + }
> +
> + return irq_id;
> +}
> +
> +/**
> + * mtk_pci_get_virq_id() - Get the Linux virtual IRQ for a hardware IRQ ID
> + * @mdev: MTK MD device
> + * @irq_id: Hardware IRQ ID
> + *
> + * Return: Virtual IRQ number on success, negative error code on failure.
> + */
> +int mtk_pci_get_virq_id(struct mtk_md_dev *mdev, int irq_id)
> +{
> + struct pci_dev *pdev = to_pci_dev(mdev->dev);
> + struct mtk_pci_priv *priv = mdev->hw_priv;
> +
> + if (irq_id < 0 || irq_id >= priv->irq_cnt)
> + return -EINVAL;
> +
> + return pci_irq_vector(pdev, irq_id);
> +}
> +
> +/**
> + * mtk_pci_register_irq() - Register a callback for a hardware IRQ
> + * @mdev: MTK MD device
> + * @irq_id: Hardware IRQ ID
> + * @irq_cb: Callback function
> + * @data: Private data passed to callback
> + *
> + * Return: 0 on success, negative error code on failure.
> + */
> +int mtk_pci_register_irq(struct mtk_md_dev *mdev, int irq_id,
> + int (*irq_cb)(int irq_id, void *data), void *data)
> +{
> + struct mtk_pci_priv *priv = mdev->hw_priv;
> +
> + if ((irq_id < 0 || irq_id >= MTK_IRQ_CNT_MAX) || !irq_cb)
> + return -EINVAL;
> +
> + spin_lock(&priv->irq_cb_lock);
> + if (priv->irq_cb_list[irq_id]) {
> + spin_unlock(&priv->irq_cb_lock);
> + dev_err(mdev->dev,
> + "Unable to register irq, irq_id=%d, it's already been register by %ps.\n",
> + irq_id, priv->irq_cb_list[irq_id]);
> + return -EFAULT;
> + }
> + priv->irq_cb_data[irq_id] = data;
> + smp_wmb(); /* Ensure data is visible before callback */
> + WRITE_ONCE(priv->irq_cb_list[irq_id], irq_cb);
> + spin_unlock(&priv->irq_cb_lock);
> +
> + return 0;
> +}
> +
> +/**
> + * mtk_pci_unregister_irq() - Unregister a hardware IRQ callback
> + * @mdev: MTK MD device
> + * @irq_id: Hardware IRQ ID
> + *
> + * Return: 0 on success, negative error code on failure.
> + */
> +int mtk_pci_unregister_irq(struct mtk_md_dev *mdev, int irq_id)
> +{
> + struct mtk_pci_priv *priv = mdev->hw_priv;
> + int virq_id;
> +
> + if (irq_id < 0 || irq_id >= MTK_IRQ_CNT_MAX)
> + return -EINVAL;
> +
> + if (!READ_ONCE(priv->irq_cb_list[irq_id])) {
> + dev_err(mdev->dev, "irq_id=%d has not been registered\n", irq_id);
> + return -EFAULT;
> + }
> +
> + /* mtk_pci_irq_handler() loads the callback and its data separately, so
> + * the data may only be cleared once no handler can still hold a live
> + * callback pointer.
> + */
> + mtk_pci_mask_irq(mdev, irq_id);
> +
> + spin_lock(&priv->irq_cb_lock);
> + WRITE_ONCE(priv->irq_cb_list[irq_id], NULL);
> + spin_unlock(&priv->irq_cb_lock);
> +
> + virq_id = mtk_pci_get_virq_id(mdev, irq_id);
> + if (virq_id >= 0)
> + synchronize_irq(virq_id);
> +
> + priv->irq_cb_data[irq_id] = NULL;
> +
> + return 0;
> +}
> +
> +/**
> + * mtk_pci_mask_irq() - Mask (disable) a hardware IRQ
> + * @mdev: MTK MD device
> + * @irq_id: Hardware IRQ ID
> + *
> + * Return: 0 on success, negative error code on failure.
> + */
> +int mtk_pci_mask_irq(struct mtk_md_dev *mdev, int irq_id)
> +{
> + struct mtk_pci_priv *priv = mdev->hw_priv;
> +
> + if (irq_id < 0 || irq_id >= MTK_IRQ_CNT_MAX) {
> + dev_err(mdev->dev, "Failed to mask irq: input irq_id=%d\n", irq_id);
> + return -EINVAL;
> + }
> +
> + mtk_pci_mac_write32(priv, REG_IMASK_HOST_MSIX_CLR_GRP0_0, BIT(irq_id));
> +
> + return 0;
> +}
> +
> +/**
> + * mtk_pci_unmask_irq() - Unmask (enable) a hardware IRQ
> + * @mdev: MTK MD device
> + * @irq_id: Hardware IRQ ID
> + *
> + * Return: 0 on success, negative error code on failure.
> + */
> +int mtk_pci_unmask_irq(struct mtk_md_dev *mdev, int irq_id)
> +{
> + struct mtk_pci_priv *priv = mdev->hw_priv;
> +
> + if (irq_id < 0 || irq_id >= MTK_IRQ_CNT_MAX) {
> + dev_err(mdev->dev, "Failed to unmask irq: input irq_id=%d\n", irq_id);
> + return -EINVAL;
> + }
> +
> + mtk_pci_mac_write32(priv, REG_IMASK_HOST_MSIX_SET_GRP0_0, BIT(irq_id));
> +
> + return 0;
> +}
> +
> +/**
> + * mtk_pci_clear_irq() - Clear (acknowledge) a hardware IRQ
> + * @mdev: MTK MD device
> + * @irq_id: Hardware IRQ ID
> + *
> + * Return: 0 on success, negative error code on failure.
> + */
> +int mtk_pci_clear_irq(struct mtk_md_dev *mdev, int irq_id)
> +{
> + struct mtk_pci_priv *priv = mdev->hw_priv;
> +
> + if (irq_id < 0 || irq_id >= MTK_IRQ_CNT_MAX) {
> + dev_err(mdev->dev, "Failed to clear irq: input irq_id=%d\n", irq_id);
> + return -EINVAL;
> + }
> +
> + mtk_pci_mac_write32(priv, REG_MSIX_ISTATUS_HOST_GRP0_0, BIT(irq_id));
> +
> + return 0;
> +}
> +
> +static u32 mtk_pci_ext_d2h_evt_hw_bits(u32 chs)
> +{
> + u32 hw_bits = 0;
> +
> + SET_HW_BITS(hw_bits, chs, MHCCIF_EP2RC_EVT_BOOT_FLOW_SYNC,
> + DEV_EVT_D2H_BOOT_FLOW_SYNC);
> + SET_HW_BITS(hw_bits, chs, MHCCIF_EP2RC_EVT_ASYNC_HS_NOTIFY_SAP,
> + DEV_EVT_D2H_ASYNC_HS_NOTIFY_SAP);
> + SET_HW_BITS(hw_bits, chs, MHCCIF_EP2RC_EVT_ASYNC_HS_NOTIFY_MD,
> + DEV_EVT_D2H_ASYNC_HS_NOTIFY_MD);
> +
> + return hw_bits;
> +}
> +
> +static u32 mtk_pci_ext_d2h_evt_chs(u32 hw_bits)
> +{
> + u32 chs = 0;
> +
> + if (!hw_bits)
> + return chs;
> +
> + chs = FIELD_PREP(DEV_EVT_D2H_BOOT_FLOW_SYNC,
> + FIELD_GET(MHCCIF_EP2RC_EVT_BOOT_FLOW_SYNC, hw_bits)) |
> + FIELD_PREP(DEV_EVT_D2H_ASYNC_HS_NOTIFY_SAP,
> + FIELD_GET(MHCCIF_EP2RC_EVT_ASYNC_HS_NOTIFY_SAP, hw_bits)) |
> + FIELD_PREP(DEV_EVT_D2H_ASYNC_HS_NOTIFY_MD,
> + FIELD_GET(MHCCIF_EP2RC_EVT_ASYNC_HS_NOTIFY_MD, hw_bits));
> +
> + return chs;
> +}
> +
> +/**
> + * mtk_pci_register_ext_evt() - Register a callback for MHCCIF device events
> + * @mdev: MTK MD device
> + * @chs: Bitmask of event channels to register
> + * @evt_cb: Callback function
> + * @data: Private data passed to callback
> + *
> + * Return: 0 on success, negative error code on failure.
> + */
> +int mtk_pci_register_ext_evt(struct mtk_md_dev *mdev, u32 chs,
> + int (*evt_cb)(u32 status, void *data), void *data)
> +{
> + struct mtk_pci_priv *priv = mdev->hw_priv;
> + struct mtk_mhccif_cb *cb;
> + int ret = 0;
> +
> + if (!chs || !evt_cb)
> + return -EINVAL;
> +
> + spin_lock_bh(&priv->mhccif_lock);
> + list_for_each_entry(cb, &priv->mhccif_cb_list, entry) {
> + if (cb->chs & chs) {
> + ret = -EFAULT;
> + dev_err(mdev->dev,
> + "Unable to register evt, intersection: chs=0x%08x&0x%08x cb=%ps\n",
> + chs, cb->chs, cb->evt_cb);
> + goto err_spin_unlock;
> + }
> + }
> + cb = kzalloc(sizeof(*cb), GFP_ATOMIC);
> + if (!cb) {
> + ret = -ENOMEM;
> + goto err_spin_unlock;
> + }
> + cb->evt_cb = evt_cb;
> + cb->data = data;
> + cb->chs = chs;
> + list_add_tail(&cb->entry, &priv->mhccif_cb_list);
> +err_spin_unlock:
> + spin_unlock_bh(&priv->mhccif_lock);
> +
> + return ret;
> +}
> +
> +/**
> + * mtk_pci_unregister_ext_evt() - Unregister an MHCCIF device event callback
> + * @mdev: MTK MD device
> + * @chs: Bitmask of event channels to unregister
> + */
> +void mtk_pci_unregister_ext_evt(struct mtk_md_dev *mdev, u32 chs)
> +{
> + struct mtk_pci_priv *priv = mdev->hw_priv;
> + struct mtk_mhccif_cb *cb, *next;
> +
> + if (!chs)
> + return;
> +
> + spin_lock_bh(&priv->mhccif_lock);
> + list_for_each_entry_safe(cb, next, &priv->mhccif_cb_list, entry) {
> + if (cb->chs == chs) {
> + list_del(&cb->entry);
> + kfree(cb);
> + goto out;
> + }
> + }
> + dev_warn(mdev->dev,
> + "Unable to unregister evt, no chs=0x%08x has been registered.\n", chs);
> +out:
> + spin_unlock_bh(&priv->mhccif_lock);
> +}
> +
> +/**
> + * mtk_pci_mask_ext_evt() - Mask (disable) MHCCIF device events
> + * @mdev: MTK MD device
> + * @chs: Bitmask of event channels to mask
> + */
> +void mtk_pci_mask_ext_evt(struct mtk_md_dev *mdev, u32 chs)
> +{
> + u32 hw_bits = mtk_pci_ext_d2h_evt_hw_bits(chs);
> +
> + mtk_pci_write32(mdev, MTK_MHCCIF_RC_BASE_ADDR +
> + MHCCIF_EP2RC_SW_INT_EAP_MASK_SET, hw_bits);
> +}
> +
> +/**
> + * mtk_pci_unmask_ext_evt() - Unmask (enable) MHCCIF device events
> + * @mdev: MTK MD device
> + * @chs: Bitmask of event channels to unmask
> + */
> +void mtk_pci_unmask_ext_evt(struct mtk_md_dev *mdev, u32 chs)
> +{
> + u32 hw_bits = mtk_pci_ext_d2h_evt_hw_bits(chs);
> +
> + mtk_pci_write32(mdev, MTK_MHCCIF_RC_BASE_ADDR +
> + MHCCIF_EP2RC_SW_INT_EAP_MASK_CLR, hw_bits);
> +}
> +
> +static u32 mtk_pci_ext_h2d_evt_hw_bits(u32 chs)
> +{
> + u32 hw_bits = 0;
> +
> + SET_HW_BITS(hw_bits, chs, MHCCIF_RC2EP_EVT_DEVICE_RESET,
> + DEV_EVT_H2D_DEVICE_RESET);
> + return hw_bits;
> +}
> +
> +/**
> + * mtk_pci_send_ext_evt() - Send an MHCCIF event to the modem
> + * @mdev: MTK MD device
> + * @ch: Event channel to trigger (must be a single bit)
> + *
> + * Return: 0 on success, negative error code on failure.
> + */
> +int mtk_pci_send_ext_evt(struct mtk_md_dev *mdev, u32 ch)
> +{
> + u32 rc_base = MTK_MHCCIF_RC_BASE_ADDR;
> + u32 hw_bits;
> +
> + /* Only allow one ch to be triggered at a time */
> + if (!is_power_of_2(ch)) {
> + dev_err(mdev->dev, "Unsupported ext evt ch=0x%08x\n", ch);
> + return -EINVAL;
> + }
> +
> + hw_bits = mtk_pci_ext_h2d_evt_hw_bits(ch);
> + if (!hw_bits) {
> + dev_err(mdev->dev, "Unmapped ext evt ch=0x%08x\n", ch);
> + return -EINVAL;
> + }
> +
> + mtk_pci_write32(mdev, rc_base + MHCCIF_RC2EP_SW_BSY, hw_bits);
> + mtk_pci_write32(mdev, rc_base + MHCCIF_RC2EP_SW_TCHNUM, ffs(hw_bits) - 1);
> + return 0;
> +}
> +
> +static u32 mtk_pci_get_ext_evt_hw_status(struct mtk_md_dev *mdev)
> +{
> + return mtk_pci_read32(mdev, MTK_MHCCIF_RC_BASE_ADDR +
> + MHCCIF_EP2RC_SW_INT_STS);
> +}
> +
> +static void mtk_pci_ack_ext_evt_hw(struct mtk_md_dev *mdev, u32 hw_bits)
> +{
> + mtk_pci_write32(mdev, MTK_MHCCIF_RC_BASE_ADDR +
> + MHCCIF_EP2RC_SW_INT_ACK, hw_bits);
> + /* Ensure the ack lands before level 1 is cleared */
> + mtk_pci_read32(mdev, MTK_MHCCIF_RC_BASE_ADDR +
> + MHCCIF_EP2RC_SW_INT_STS);
> +}
> +
> +/**
> + * mtk_pci_pldr() - Reset the modem via its ACPI MRST._RST method
> + * @mdev: MTK MD device
> + *
> + * Return:
> + * * 0 - Success, device was reset.
> + * * -ENODEV - No ACPI, no handle or no MRST._RST method. Device
> + * untouched.
> + * * -EIO - MRST._RST failed. Device untouched, still running;
> + * a different reset may be attempted.
> + */
> +int mtk_pci_pldr(struct mtk_md_dev *mdev)
> +{
> + acpi_status acpi_ret;
> + acpi_handle handle;
> +
> + if (acpi_disabled) {
> + dev_dbg(mdev->dev, "Unsupported, acpi function isn't enable\n");
> + return -ENODEV;
> + }
> +
> + handle = ACPI_HANDLE(mdev->dev);
> + if (!handle) {
> + dev_dbg(mdev->dev, "Unsupported, acpi handle isn't found\n");
> + return -ENODEV;
> + }
> + if (!acpi_has_method(handle, "MRST._RST")) {
> + dev_dbg(mdev->dev, "Unsupported, pldr method isn't supported\n");
> + return -ENODEV;
> + }
> + acpi_ret = acpi_evaluate_object(handle, "MRST._RST", NULL, NULL);
> + if (ACPI_FAILURE(acpi_ret)) {
> + dev_err(mdev->dev, "Failed to execute MRST._RST method: %s\n",
> + acpi_format_exception(acpi_ret));
> + return -EIO;
> + }
> +
> + return 0;
> +}
> +
> +/**
> + * mtk_pci_link_check() - Check if the PCIe link to the modem is active
> + * @mdev: MTK MD device
> + *
> + * Return: true if the device is present, false otherwise.
> + */
> +bool mtk_pci_link_check(struct mtk_md_dev *mdev)
> +{
> + return pci_device_is_present(to_pci_dev(mdev->dev));
> +}
> +
> +static void mtk_mhccif_isr_work(struct work_struct *work)
> +{
> + struct mtk_pci_priv *priv =
> + container_of(work, struct mtk_pci_priv, mhccif_work);
> + struct mtk_md_dev *mdev = priv->irq_desc->mdev;
> + struct mtk_mhccif_cb *cb;
> + u32 stat, mask, chs;
> +
> + stat = mtk_pci_get_ext_evt_hw_status(mdev);
> + mask = mtk_pci_read32(mdev, MTK_MHCCIF_RC_BASE_ADDR
> + + MHCCIF_EP2RC_SW_INT_EAP_MASK);
> + if (unlikely(stat == U32_MAX && !(mtk_pci_link_check(mdev)))) {
> + /* When link failed, we don't need to unmask/clear. */
> + dev_err(mdev->dev, "Failed to check link in MHCCIF handler.\n");
> + return;
> + }
> +
> + stat &= ~mask;
> + /* Acknowledge level 2 before dispatch: an event that re-asserts
> + * while a callback runs must survive as a new status bit.
> + */
> + if (stat)
> + mtk_pci_ack_ext_evt_hw(mdev, stat);
> +
> + chs = mtk_pci_ext_d2h_evt_chs(stat);
> + /* Callbacks must not sleep or modify mhccif_cb_list */
> + spin_lock_bh(&priv->mhccif_lock);
> + list_for_each_entry(cb, &priv->mhccif_cb_list, entry) {
> + if (cb->chs & chs)
> + cb->evt_cb(cb->chs & chs, cb->data);
> + }
> + spin_unlock_bh(&priv->mhccif_lock);
> +
> + mtk_pci_clear_irq(mdev, priv->mhccif_irq_id);
> + mtk_pci_unmask_irq(mdev, priv->mhccif_irq_id);
> +}
> +
> +static const struct pci_device_id t9xx_pci_table[] = {
> + { PCI_DEVICE(PCI_VENDOR_ID_MEDIATEK, 0x0900),
> + MTK_PCI_CLASS, PCI_ANY_ID },
> + { PCI_DEVICE(0x03f0, 0x01ca), /* HP RMM-G4 */
> + MTK_PCI_CLASS, PCI_ANY_ID },
> + {/* end: all zeroes */}
> +};
> +
> +MODULE_DEVICE_TABLE(pci, t9xx_pci_table);
> +
> +static int mtk_pci_atr_init(struct mtk_md_dev *mdev)
> +{
> + struct pci_dev *pdev = to_pci_dev(mdev->dev);
> + struct mtk_pci_priv *priv = mdev->hw_priv;
> + struct mtk_atr_cfg cfg;
> + int port, ret;
> +
> + mtk_pci_atr_disable(priv);
> +
> + /* Config ATR for RC to access device's register */
> + cfg.src_addr = pci_bus_address(pdev, MTK_BAR_2_3_IDX);
> + cfg.size = ATR_PCIE_REG_SIZE;
> + cfg.trsl_addr = ATR_PCIE_REG_TRSL_ADDR;
> + cfg.port = ATR_PCIE_REG_PORT;
> + cfg.table = ATR_PCIE_REG_TABLE_NUM;
> + cfg.trsl_id = ATR_PCIE_REG_TRSL_PORT;
> + cfg.trsl_param = 0x0;
> + cfg.transparent = 0x0;
> + ret = mtk_pci_setup_atr(mdev, &cfg);
> + if (ret)
> + return ret;
> +
> + /* Config ATR for EP to access RC's memory */
> + for (port = ATR_SRC_AXIS_0; port <= ATR_SRC_AXIS_3; port++) {
> + cfg.src_addr = ATR_PCIE_DEV_DMA_SRC_ADDR;
> + cfg.size = ATR_PCIE_DEV_DMA_SIZE;
> + cfg.trsl_addr = ATR_PCIE_DEV_DMA_TRSL_ADDR;
> + cfg.port = port;
> + cfg.table = ATR_PCIE_DEV_DMA_TABLE_NUM;
> + cfg.trsl_id = ATR_DST_PCI_TRX;
> + cfg.trsl_param = 0x0;
> + /* Enable transparent translation */
> + cfg.transparent = ATR_PCIE_DEV_DMA_TRANSPARENT;
> + ret = mtk_pci_setup_atr(mdev, &cfg);
> + if (ret)
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int mtk_pci_bar_init(struct mtk_md_dev *mdev)
> +{
> + struct pci_dev *pdev = to_pci_dev(mdev->dev);
> + struct mtk_pci_priv *priv = mdev->hw_priv;
> +
> + /* Fixed offsets used on these mappings (MSI-X registers up to
> + * 0x3103 on BAR0/1, the ATR-biased MHCCIF window on BAR2/3) are
> + * guaranteed by the only two devices this driver binds (0x0900,
> + * 0x01CA), whose BAR sizes are fixed by hardware; an undersized
> + * BAR here is impossible, so no pci_resource_len() checks.
> + */
> + priv->mac_reg_base = pcim_iomap_region(pdev, MTK_BAR_0_1_IDX,
> + mdev->dev_str);
> + if (IS_ERR(priv->mac_reg_base)) {
> + dev_err(mdev->dev, "Failed to map BAR0/1\n");
> + return PTR_ERR(priv->mac_reg_base);
> + }
> +
> + priv->bar23_addr = pcim_iomap_region(pdev, MTK_BAR_2_3_IDX,
> + mdev->dev_str);
> + if (IS_ERR(priv->bar23_addr)) {
> + dev_err(mdev->dev, "Failed to map BAR2/3\n");
> + return PTR_ERR(priv->bar23_addr);
> + }
> +
> + /* We use MD view base address "0" to observe registers */
> + priv->ext_reg_base = priv->bar23_addr - ATR_PCIE_REG_TRSL_ADDR;
> +
> + return 0;
> +}
> +
> +static int mtk_mhccif_irq_cb(int irq_id, void *data)
> +{
> + struct mtk_md_dev *mdev = data;
> + struct mtk_pci_priv *priv;
> +
> + priv = mdev->hw_priv;
> + queue_work(system_highpri_wq, &priv->mhccif_work);
> +
> + return 0;
> +}
> +
> +static int mtk_mhccif_init(struct mtk_md_dev *mdev)
> +{
> + struct mtk_pci_priv *priv = mdev->hw_priv;
> + int ret;
> +
> + INIT_LIST_HEAD(&priv->mhccif_cb_list);
> + spin_lock_init(&priv->mhccif_lock);
> + INIT_WORK(&priv->mhccif_work, mtk_mhccif_isr_work);
> +
> + /* The write below goes through the BAR 2/3 ATR window, so this
> + * function must run after mtk_pci_atr_init().
> + * Mask every channel; consumers unmask the channels they need.
> + * Do NOT ack here: EP2RC status bits are latched one-shot
> + * notifications (e.g. BOOT_FLOW_SYNC raised before the driver
> + * loads) that the device never re-sends. Masking blocks
> + * delivery but preserves the bit for delivery on unmask; an
> + * ack would erase it and the boot flow would hang silently.
> + */
> + mtk_pci_write32(mdev, MTK_MHCCIF_RC_BASE_ADDR +
> + MHCCIF_EP2RC_SW_INT_EAP_MASK_SET, U32_MAX);
> +
> + ret = mtk_pci_get_irq_id(mdev, MTK_IRQ_SRC_MHCCIF);
> + if (ret < 0) {
> + dev_err(mdev->dev, "Failed to get mhccif_irq_id. ret=%d\n", ret);
> + return ret;
> + }
> + priv->mhccif_irq_id = ret;
> +
> + ret = mtk_pci_register_irq(mdev, priv->mhccif_irq_id, mtk_mhccif_irq_cb, mdev);
> + if (ret) {
> + dev_err(mdev->dev, "Failed to register mhccif_irq callback\n");
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static void mtk_mhccif_exit(struct mtk_md_dev *mdev)
> +{
> + struct mtk_pci_priv *priv = mdev->hw_priv;
> + struct mtk_mhccif_cb *cb, *tmp;
> +
> + mtk_pci_unregister_irq(mdev, priv->mhccif_irq_id);
> + cancel_work_sync(&priv->mhccif_work);
> + /* The work unmasks the source on its way out, so leave it masked. */
> + mtk_pci_mask_irq(mdev, priv->mhccif_irq_id);
> +
> + list_for_each_entry_safe(cb, tmp, &priv->mhccif_cb_list, entry) {
> + list_del(&cb->entry);
> + kfree(cb);
> + }
> +}
> +
> +static irqreturn_t mtk_pci_irq_handler(struct mtk_md_dev *mdev, u32 irq_state)
> +{
> + struct mtk_pci_priv *priv = mdev->hw_priv;
> + int irq_id;
> +
> + /* Check whether each set bit has a callback, if has, call it */
> + do {
> + int (*cb)(int irq_id, void *data);
> +
> + irq_id = fls(irq_state) - 1;
> + irq_state &= ~BIT(irq_id);
> + cb = READ_ONCE(priv->irq_cb_list[irq_id]);
> + if (likely(cb)) {
> + smp_rmb(); /* Ensure data is read after callback */
> + cb(irq_id, priv->irq_cb_data[irq_id]);
> + } else {
> + dev_err_ratelimited(mdev->dev,
> + "Unhandled irq_id=%d, no callback for it.\n",
> + irq_id);
> + mtk_pci_clear_irq(mdev, irq_id);
> + }
> + } while (irq_state);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t mtk_pci_irq_msix(int irq, void *data)
> +{
> + struct mtk_pci_irq_desc *irq_desc = data;
> + struct mtk_md_dev *mdev = irq_desc->mdev;
> + struct mtk_pci_priv *priv;
> + u32 irq_state, irq_enable;
> +
> + priv = mdev->hw_priv;
> + irq_state = mtk_pci_mac_read32(priv, REG_MSIX_ISTATUS_HOST_GRP0_0);
> + irq_enable = mtk_pci_mac_read32(priv, REG_IMASK_HOST_MSIX_GRP0_0);
> + irq_state &= irq_enable;
> +
> + if (unlikely(irq_state == U32_MAX && irq_enable == U32_MAX))
> + return IRQ_NONE; /* device gone */
> +
> + irq_state &= irq_desc->msix_bits; /* scope to this vector */
> + if (unlikely(!irq_state))
> + return IRQ_NONE;
> +
> + /* Mask the bit; the consumer unmasks it when it is done */
> + mtk_pci_mac_write32(priv, REG_IMASK_HOST_MSIX_CLR_GRP0_0, irq_state);
> +
> + return mtk_pci_irq_handler(mdev, irq_state);
> +}
> +
> +static int mtk_pci_request_irq_msix(struct mtk_md_dev *mdev)
> +{
> + struct mtk_pci_priv *priv = mdev->hw_priv;
> + struct mtk_pci_irq_desc *irq_desc;
> + struct pci_dev *pdev;
> + int ret, i;
> +
> + pdev = to_pci_dev(mdev->dev);
> + irq_desc = priv->irq_desc;
> +
> + priv->irq_cnt = MTK_IRQ_CNT_MAX;
> +
> + for (i = 0; i < MTK_IRQ_CNT_MAX; i++) {
> + irq_desc[i].mdev = mdev;
> + irq_desc[i].msix_bits = BIT(i);
> + snprintf(irq_desc[i].name, MTK_IRQ_NAME_LEN, "msix%d-%s", i, mdev->dev_str);
> + ret = pci_request_irq(pdev, i, mtk_pci_irq_msix, NULL,
> + &irq_desc[i], "%s", irq_desc[i].name);
> + if (ret) {
> + dev_err(mdev->dev, "Failed to request %s: ret=%d\n",
> + irq_desc[i].name, ret);
> + for (i--; i >= 0; i--)
> + pci_free_irq(pdev, i, &irq_desc[i]);
> + priv->irq_cnt = 0;
> + return ret;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static int mtk_pci_request_irq(struct mtk_md_dev *mdev)
> +{
> + struct pci_dev *pdev = to_pci_dev(mdev->dev);
> + int ret;
> +
> + ret = pci_alloc_irq_vectors(pdev, MTK_IRQ_CNT_MAX,
> + MTK_IRQ_CNT_MAX, PCI_IRQ_MSIX);
> + if (ret < 0) {
> + dev_err(mdev->dev,
> + "Unable to alloc %d MSI-X vectors: ret=%d\n",
> + MTK_IRQ_CNT_MAX, ret);
> + return ret;
> + }
> +
> + ret = mtk_pci_request_irq_msix(mdev);
> + if (ret)
> + pci_free_irq_vectors(pdev);
> +
> + return ret;
> +}
> +
> +static void mtk_pci_free_irq(struct mtk_md_dev *mdev)
> +{
> + struct pci_dev *pdev = to_pci_dev(mdev->dev);
> + struct mtk_pci_priv *priv = mdev->hw_priv;
> + int i;
> +
> + for (i = 0; i < priv->irq_cnt; i++)
> + pci_free_irq(pdev, i, &priv->irq_desc[i]);
> +
> + pci_free_irq_vectors(pdev);
> + priv->irq_cnt = 0;
> +}
> +
> +static int mtk_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> +{
> + struct device *dev = &pdev->dev;
> + struct mtk_pci_priv *priv;
> + struct mtk_md_dev *mdev;
> + int ret;
> +
> + mdev = devm_kzalloc(dev, sizeof(*mdev), GFP_KERNEL);
> + if (!mdev) {
> + ret = -ENOMEM;
> + goto log_err;
> + }
> + mdev->dev = dev;
> +
> + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> + if (!priv) {
> + ret = -ENOMEM;
> + goto log_err;
> + }
> +
> + pci_set_drvdata(pdev, mdev);
> + priv->mdev = mdev;
> + mdev->hw_ver = pdev->device;
> + mdev->hw_priv = priv;
> + mdev->dev = dev;
> + snprintf(mdev->dev_str, MTK_DEV_STR_LEN, "%02x%02x%d",
> + pdev->bus->number, PCI_SLOT(pdev->devfn), PCI_FUNC(pdev->devfn));
> + if (pdev->state_saved)
> + pci_restore_state(pdev);
> +
> + ret = pci_enable_device(pdev);
> + if (ret) {
> + dev_err(mdev->dev, "Failed to enable pci device.\n");
> + goto log_err;
> + }
> +
> + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
> + if (ret) {
> + dev_err(mdev->dev, "Failed to set DMA Mask and Coherent. (ret=%d)\n", ret);
> + goto disable_dev;
> + }
> +
> + ret = mtk_pci_bar_init(mdev);
> + if (ret)
> + goto disable_dev;
> +
> + ret = mtk_pci_atr_init(mdev);
> + if (ret)
> + goto disable_dev;
> +
> + spin_lock_init(&priv->irq_cb_lock);
> +
> + ret = mtk_mhccif_init(mdev);
> + if (ret)
> + goto disable_dev;
> +
> + /* Mask every source before the handlers go in, so a source
> + * left enabled by firmware or a previous bind cannot fire
> + * into a half-initialised driver.
> + */
> + mtk_pci_mac_write32(priv, REG_IMASK_HOST_MSIX_CLR_GRP0_0, U32_MAX);
> +
> + ret = mtk_pci_request_irq(mdev);
> + if (ret)
> + goto free_mhccif;
> +
> + pci_set_master(pdev);
> + mtk_pci_unmask_irq(mdev, priv->mhccif_irq_id);
> +
> + if (!mtk_pci_link_check(mdev)) {
> + ret = -ENOLINK;
> + goto clear_master;
> + }
> +
> + ret = pci_save_state(pdev);
> + if (ret) {
> + dev_err(mdev->dev, "Failed to save PCI state: %d\n", ret);
> + goto clear_master;
> + }
> +
> + priv->saved_state = pci_store_saved_state(pdev);
> + if (!priv->saved_state) {
> + ret = -ENOMEM;
> + goto clear_master;
> + }
> +
> + return 0;
> +
> +clear_master:
> + pci_clear_master(pdev);
> + mtk_pci_free_irq(mdev);
> +free_mhccif:
> + mtk_mhccif_exit(mdev);
> +disable_dev:
> + pci_disable_device(pdev);
> +log_err:
> + dev_err(dev, "Failed to probe device, ret=%d\n", ret);
> +
> + return ret;
> +}
> +
> +static void mtk_pci_remove(struct pci_dev *pdev)
> +{
> + struct mtk_md_dev *mdev = pci_get_drvdata(pdev);
> + struct mtk_pci_priv *priv = mdev->hw_priv;
> + struct device *dev = &pdev->dev;
> + int ret;
> +
> + /* Silence every source before tearing anything down. */
> + mtk_pci_mac_write32(priv, REG_IMASK_HOST_MSIX_CLR_GRP0_0, U32_MAX);
> +
> + /* Free the vectors first: once no handler can run, the unmask at the
> + * tail of mtk_mhccif_isr_work() cannot re-open the source behind
> + * mtk_mhccif_exit()'s back.
> + */
> + mtk_pci_free_irq(mdev);
> + mtk_mhccif_exit(mdev);
> + pci_clear_master(pdev);
> + pci_disable_device(pdev);
> +
> + /* Reset last: the endpoint comes back at power-on defaults, so no MMIO
> + * and no MSI-X teardown may follow it.
> + */
> + ret = mtk_pci_pldr(mdev);
> + if (ret && mtk_pci_link_check(mdev)) {
> + dev_warn(dev, "PLDR failed (%d), trying MHCCIF reset\n", ret);
> + if (mtk_pci_send_ext_evt(mdev, DEV_EVT_H2D_DEVICE_RESET))
> + dev_err(dev, "MHCCIF reset failed\n");
> + /* Unlike MRST._RST the doorbell returns before the device
> + * has reset, so let it settle before the restore below.
> + */
> + msleep(MTK_MHCCIF_RESET_DELAY_MS);
> + }
> +
> + /* Without this a runtime-PM suspend after unbind would snapshot the
> + * reset state over our copy, and whoever binds next finds BARs the
> + * device does not decode.
> + */
> + pci_load_and_free_saved_state(pdev, &priv->saved_state);
> + pci_restore_state(pdev);
> + /* The state was saved after pci_set_master(), so the restore just
> + * re-enabled bus mastering on an unbound device - drop it again.
> + */
> + pci_clear_master(pdev);
> +}
> +
> +static pci_ers_result_t mtk_pci_error_detected(struct pci_dev *pdev,
> + pci_channel_state_t state)
> +{
> + struct mtk_md_dev *mdev = pci_get_drvdata(pdev);
> +
> + dev_err(mdev->dev, "AER detected: pci_channel_state_t=%u\n", state);
> +
> + /* AER recovery not supported, disconnect the device */
> + return PCI_ERS_RESULT_DISCONNECT;
> +}
> +
> +static const struct pci_error_handlers mtk_pci_err_handler = {
> + .error_detected = mtk_pci_error_detected,
> +};
> +
> +static struct pci_driver mtk_pci_drv = {
> + .name = "mtk_pci_drv",
> + .id_table = t9xx_pci_table,
> + .probe = mtk_pci_probe,
> + .remove = mtk_pci_remove,
> + .err_handler = &mtk_pci_err_handler
> +};
> +
> +module_pci_driver(mtk_pci_drv);
> +
> +MODULE_DESCRIPTION("MediaTek T9xx PCIe WWAN driver");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/net/wwan/t9xx/pcie/mtk_pci.h b/drivers/net/wwan/t9xx/pcie/mtk_pci.h
> new file mode 100644
> index 000000000000..80c1a40f98d5
> --- /dev/null
> +++ b/drivers/net/wwan/t9xx/pcie/mtk_pci.h
> @@ -0,0 +1,140 @@
> +/* SPDX-License-Identifier: GPL-2.0-only
> + *
> + * Copyright (c) 2022, MediaTek Inc.
> + */
> +
> +#ifndef __MTK_PCI_H__
> +#define __MTK_PCI_H__
> +
> +#include <linux/pci.h>
> +
> +#include "../mtk_dev.h"
> +
> +enum mtk_irq_src {
> + MTK_IRQ_SRC_MIN,
> + MTK_IRQ_SRC_MHCCIF,
> + MTK_IRQ_SRC_CLDMA0,
> + MTK_IRQ_SRC_CLDMA1,
> + MTK_IRQ_SRC_MAX
> +};
> +
> +enum mtk_atr_src_port {
> + ATR_SRC_PCI_WIN0 = 0,
> + ATR_SRC_PCI_WIN1,
> + ATR_SRC_AXIS_0,
> + ATR_SRC_AXIS_1,
> + ATR_SRC_AXIS_2,
> + ATR_SRC_AXIS_3,
> +};
> +
> +enum mtk_atr_dst_port {
> + ATR_DST_PCI_TRX = 0,
> + ATR_DST_AXIM_0 = 4,
> +};
> +
> +#define MTK_PCI_CLASS 0x0D4000
> +
> +#define MTK_BAR_0_1_IDX 0
> +#define MTK_BAR_2_3_IDX 2
> +
> +#define MTK_IRQ_CNT_MAX 32
> +#define MTK_IRQ_NAME_LEN 32
> +
> +#define ATR_PORT_OFFSET 0x100
> +#define ATR_TABLE_OFFSET 0x20
> +#define ATR_TABLE_NUM_PER_ATR 8
> +#define ATR_PCIE_REG_TRSL_ADDR 0x10000000
> +#define ATR_PCIE_REG_SIZE 0x00400000
> +#define ATR_PCIE_REG_PORT ATR_SRC_PCI_WIN0
> +#define ATR_PCIE_REG_TABLE_NUM 1
> +#define ATR_PCIE_REG_TRSL_PORT ATR_DST_AXIM_0
> +#define ATR_PCIE_DEV_DMA_SRC_ADDR 0x00000000
> +#define ATR_PCIE_DEV_DMA_TRANSPARENT 1
> +#define ATR_PCIE_DEV_DMA_SIZE 0
> +#define ATR_PCIE_DEV_DMA_TABLE_NUM 0
> +#define ATR_PCIE_DEV_DMA_TRSL_ADDR 0x00000000
> +
> +struct mtk_pci_irq_desc {
> + struct mtk_md_dev *mdev;
> + u32 msix_bits;
> + char name[MTK_IRQ_NAME_LEN];
> +};
> +
> +struct mtk_pci_priv {
> + struct mtk_md_dev *mdev;
> + void __iomem *bar23_addr;
> + void __iomem *mac_reg_base;
> + void __iomem *ext_reg_base;
> + int irq_cnt;
> + /* irq_cb_lock: protects irq_cb_list[] and irq_cb_data[] */
> + spinlock_t irq_cb_lock;
> + void *irq_cb_data[MTK_IRQ_CNT_MAX];
> +
> + int (*irq_cb_list[MTK_IRQ_CNT_MAX])(int irq_id, void *data);
> + struct mtk_pci_irq_desc irq_desc[MTK_IRQ_CNT_MAX];
> + struct list_head mhccif_cb_list;
> + /* mhccif_lock: lock to protect mhccif_cb_list */
> + spinlock_t mhccif_lock;
> + struct work_struct mhccif_work;
> + int mhccif_irq_id;
> + struct pci_saved_state *saved_state;
> +};
> +
> +struct mtk_atr_cfg {
> + u64 src_addr;
> + u64 trsl_addr;
> + u64 size;
> + u32 port; /* Port number */
> + u32 table; /* Table number (8 tables for each port) */
> + u32 trsl_id;
> + u32 trsl_param;
> + u32 transparent;
> +};
> +
> +/* BAR 0/1 MMIO access */
> +static inline u32 mtk_pci_mac_read32(struct mtk_pci_priv *priv, u64 addr)
> +{
> + return ioread32(priv->mac_reg_base + addr);
> +}
> +
> +static inline void mtk_pci_mac_write32(struct mtk_pci_priv *priv, u64 addr, u32 val)
> +{
> + iowrite32(val, priv->mac_reg_base + addr);
> +}
> +
> +/* BAR 2/3 MMIO access */
> +static inline u32 mtk_pci_read32(struct mtk_md_dev *mdev, u64 addr)
> +{
> + return ioread32(((struct mtk_pci_priv *)mdev->hw_priv)->ext_reg_base + addr);
> +}
> +
> +static inline void mtk_pci_write32(struct mtk_md_dev *mdev, u64 addr, u32 val)
> +{
> + iowrite32(val, ((struct mtk_pci_priv *)mdev->hw_priv)->ext_reg_base + addr);
> +}
> +
> +/* Device operations */
> +u32 mtk_pci_get_dev_state(struct mtk_md_dev *mdev);
> +void mtk_pci_ack_dev_state(struct mtk_md_dev *mdev, u32 state);
> +/* IRQ Related operations */
> +int mtk_pci_get_irq_id(struct mtk_md_dev *mdev, enum mtk_irq_src irq_src);
> +int mtk_pci_get_virq_id(struct mtk_md_dev *mdev, int irq_id);
> +int mtk_pci_register_irq(struct mtk_md_dev *mdev, int irq_id,
> + int (*irq_cb)(int irq_id, void *data), void *data);
> +int mtk_pci_unregister_irq(struct mtk_md_dev *mdev, int irq_id);
> +int mtk_pci_mask_irq(struct mtk_md_dev *mdev, int irq_id);
> +int mtk_pci_unmask_irq(struct mtk_md_dev *mdev, int irq_id);
> +int mtk_pci_clear_irq(struct mtk_md_dev *mdev, int irq_id);
> +/* External event related */
> +int mtk_pci_register_ext_evt(struct mtk_md_dev *mdev, u32 chs,
> + int (*evt_cb)(u32 status, void *data), void *data);
> +void mtk_pci_unregister_ext_evt(struct mtk_md_dev *mdev, u32 chs);
> +void mtk_pci_mask_ext_evt(struct mtk_md_dev *mdev, u32 chs);
> +void mtk_pci_unmask_ext_evt(struct mtk_md_dev *mdev, u32 chs);
> +int mtk_pci_send_ext_evt(struct mtk_md_dev *mdev, u32 ch);
> +int mtk_pci_pldr(struct mtk_md_dev *mdev);
> +bool mtk_pci_link_check(struct mtk_md_dev *mdev);
> +int mtk_pci_setup_atr(struct mtk_md_dev *mdev, struct mtk_atr_cfg *cfg);
> +void mtk_pci_atr_disable(struct mtk_pci_priv *priv);
> +
> +#endif /* __MTK_PCI_H__ */
> diff --git a/drivers/net/wwan/t9xx/pcie/mtk_pci_reg.h b/drivers/net/wwan/t9xx/pcie/mtk_pci_reg.h
> new file mode 100644
> index 000000000000..a97ad6630dcf
> --- /dev/null
> +++ b/drivers/net/wwan/t9xx/pcie/mtk_pci_reg.h
> @@ -0,0 +1,34 @@
> +/* SPDX-License-Identifier: GPL-2.0-only
> + *
> + * Copyright (c) 2022, MediaTek Inc.
> + */
> +
> +#ifndef __MTK_PCI_REG_H__
> +#define __MTK_PCI_REG_H__
> +
> +#define REG_ATR_PCIE_WIN0_T0_SRC_ADDR_LSB 0x0600
> +#define REG_ATR_PCIE_WIN0_T0_SRC_ADDR_MSB 0x0604
> +#define REG_ATR_PCIE_WIN0_T0_TRSL_ADDR_LSB 0x0608
> +#define REG_ATR_PCIE_WIN0_T0_TRSL_ADDR_MSB 0x060C
> +#define REG_ATR_PCIE_WIN0_T0_TRSL_PARAM 0x0610
> +#define REG_PCIE_DEBUG_DUMMY_7 0x0D1C
> +#define REG_MSIX_ISTATUS_HOST_GRP0_0 0x0F00
> +#define REG_IMASK_HOST_MSIX_SET_GRP0_0 0x3000
> +#define REG_IMASK_HOST_MSIX_CLR_GRP0_0 0x3080
> +#define REG_IMASK_HOST_MSIX_GRP0_0 0x3100
> +
> +/* mhccif registers */
> +#define MHCCIF_RC2EP_SW_BSY 0x4
> +#define MHCCIF_RC2EP_SW_TCHNUM 0xC
> +#define MHCCIF_RC2EP_EVT_DEVICE_RESET BIT(13)
> +
> +#define MHCCIF_EP2RC_SW_INT_STS 0x10
> +#define MHCCIF_EP2RC_SW_INT_ACK 0x14
> +#define MHCCIF_EP2RC_SW_INT_EAP_MASK 0x20
> +#define MHCCIF_EP2RC_SW_INT_EAP_MASK_SET 0x30
> +#define MHCCIF_EP2RC_SW_INT_EAP_MASK_CLR 0x40
> +#define MHCCIF_EP2RC_EVT_BOOT_FLOW_SYNC BIT(5)
> +#define MHCCIF_EP2RC_EVT_ASYNC_HS_NOTIFY_SAP BIT(15)
> +#define MHCCIF_EP2RC_EVT_ASYNC_HS_NOTIFY_MD BIT(16)
> +
> +#endif /* __MTK_PCI_REG_H__ */
>
> --
> 2.34.1
>
>