Add mtk-vcp-mailbox driver to support the communication with
VCP remote microprocessor.
Signed-off-by: Jjian Zhou <jjian.zhou@mediatek.com>
---
drivers/mailbox/Kconfig | 9 ++
drivers/mailbox/Makefile | 2 +
drivers/mailbox/mtk-vcp-mailbox.c | 168 ++++++++++++++++++++++++
include/linux/mailbox/mtk-vcp-mailbox.h | 32 +++++
4 files changed, 211 insertions(+)
create mode 100644 drivers/mailbox/mtk-vcp-mailbox.c
create mode 100644 include/linux/mailbox/mtk-vcp-mailbox.h
diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
index 02432d4a5ccd..c28bdb855663 100644
--- a/drivers/mailbox/Kconfig
+++ b/drivers/mailbox/Kconfig
@@ -294,6 +294,15 @@ config MTK_CMDQ_MBOX
critical time limitation, such as updating display configuration
during the vblank.
+config MTK_VCP_MBOX
+ tristate "MediaTek VCP Mailbox Support"
+ depends on ARCH_MEDIATEK || COMPILE_TEST
+ help
+ Say yes here to add support for the MediaTek VCP mailbox driver.
+ The mailbox implementation provides access from the application
+ processor to Video Companion Processor Unit.
+ If unsure say N.
+
config ZYNQMP_IPI_MBOX
tristate "Xilinx ZynqMP IPI Mailbox"
depends on ARCH_ZYNQMP && OF
diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile
index 98a68f838486..07278871d254 100644
--- a/drivers/mailbox/Makefile
+++ b/drivers/mailbox/Makefile
@@ -63,6 +63,8 @@ obj-$(CONFIG_MTK_ADSP_MBOX) += mtk-adsp-mailbox.o
obj-$(CONFIG_MTK_CMDQ_MBOX) += mtk-cmdq-mailbox.o
+obj-$(CONFIG_MTK_VCP_MBOX) += mtk-vcp-mailbox.o
+
obj-$(CONFIG_ZYNQMP_IPI_MBOX) += zynqmp-ipi-mailbox.o
obj-$(CONFIG_SUN6I_MSGBOX) += sun6i-msgbox.o
diff --git a/drivers/mailbox/mtk-vcp-mailbox.c b/drivers/mailbox/mtk-vcp-mailbox.c
new file mode 100644
index 000000000000..a2a80d124e50
--- /dev/null
+++ b/drivers/mailbox/mtk-vcp-mailbox.c
@@ -0,0 +1,168 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2025 MediaTek Corporation. All rights reserved.
+ * Author: Jjian Zhou <jjian.zhou.@mediatek.com>
+ */
+
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/mailbox_controller.h>
+#include <linux/mailbox/mtk-vcp-mailbox.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+struct mtk_vcp_mbox {
+ struct mbox_controller mbox;
+ void __iomem *base;
+ struct device *dev;
+ const struct mtk_vcp_mbox_cfg *cfg;
+ struct mtk_ipi_info ipi_recv;
+ struct mbox_chan chans;
+};
+
+struct mtk_vcp_mbox_cfg {
+ u32 set_in;
+ u32 clr_out;
+};
+
+static irqreturn_t mtk_vcp_mbox_irq_thread(int irq, void *data)
+{
+ struct mtk_vcp_mbox *priv = data;
+
+ /* get irq status */
+ priv->ipi_recv.irq_status = readl(priv->base + priv->cfg->clr_out);
+
+ __ioread32_copy(priv->ipi_recv.msg, priv->base, MBOX_SLOT_MAX_SIZE / 4);
+
+ mbox_chan_received_data(&priv->chans, &priv->ipi_recv);
+
+ /* clear irq status */
+ writel(priv->ipi_recv.irq_status, priv->base + priv->cfg->clr_out);
+
+ return IRQ_HANDLED;
+}
+
+static struct mbox_chan *mtk_vcp_mbox_xlate(struct mbox_controller *mbox,
+ const struct of_phandle_args *sp)
+{
+ if (sp->args_count)
+ return NULL;
+
+ return &mbox->chans[0];
+}
+
+static int mtk_vcp_mbox_send_data(struct mbox_chan *chan, void *data)
+{
+ struct mtk_vcp_mbox *priv = chan->con_priv;
+ struct mtk_ipi_info *ipi_info = data;
+ u32 status;
+
+ if (!ipi_info->msg) {
+ dev_err(priv->dev, "msg buffer is NULL.\n");
+ return -EINVAL;
+ }
+
+ status = readl(priv->base + priv->cfg->set_in) & BIT(ipi_info->index);
+ if (status) {
+ dev_warn(priv->dev, "mailbox IPI %d is busy.\n", ipi_info->id);
+ return -EBUSY;
+ }
+
+ if (ipi_info->slot_ofs + ipi_info->len > MBOX_SLOT_MAX_SIZE)
+ return -EINVAL;
+ __iowrite32_copy(priv->base + ipi_info->slot_ofs, ipi_info->msg,
+ ipi_info->len);
+
+ writel(BIT(ipi_info->index), priv->base + priv->cfg->set_in);
+
+ return 0;
+}
+
+static bool mtk_vcp_mbox_last_tx_done(struct mbox_chan *chan)
+{
+ struct mtk_ipi_info *ipi_info = chan->active_req;
+ struct mtk_vcp_mbox *priv = chan->con_priv;
+
+ return !(readl(priv->base + priv->cfg->set_in) & BIT(ipi_info->index));
+}
+
+static const struct mbox_chan_ops mtk_vcp_mbox_chan_ops = {
+ .send_data = mtk_vcp_mbox_send_data,
+ .last_tx_done = mtk_vcp_mbox_last_tx_done,
+};
+
+static int mtk_vcp_mbox_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct mtk_vcp_mbox *priv;
+ struct mbox_controller *mbox;
+ int ret, irq;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->dev = dev;
+ priv->chans.con_priv = priv;
+ mbox = &priv->mbox;
+ mbox->dev = dev;
+ mbox->ops = &mtk_vcp_mbox_chan_ops;
+ mbox->txdone_irq = false;
+ mbox->txdone_poll = true;
+ mbox->of_xlate = mtk_vcp_mbox_xlate;
+ mbox->num_chans = 1;
+ mbox->chans = &priv->chans;
+
+ priv->ipi_recv.msg = devm_kzalloc(dev, MBOX_SLOT_MAX_SIZE, GFP_KERNEL);
+ if (!priv->ipi_recv.msg)
+ return -ENOMEM;
+
+ priv->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(priv->base))
+ return PTR_ERR(priv->base);
+
+ priv->cfg = of_device_get_match_data(dev);
+ if (!priv->cfg)
+ return -EINVAL;
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
+
+ ret = devm_request_threaded_irq(dev, irq, NULL,
+ mtk_vcp_mbox_irq_thread, IRQF_ONESHOT,
+ dev_name(dev), priv);
+ if (ret < 0)
+ return ret;
+
+ platform_set_drvdata(pdev, priv);
+
+ return devm_mbox_controller_register(dev, &priv->mbox);
+}
+
+static const struct mtk_vcp_mbox_cfg mt8196_cfg = {
+ .set_in = 0x100,
+ .clr_out = 0x10c,
+};
+
+static const struct of_device_id mtk_vcp_mbox_of_match[] = {
+ { .compatible = "mediatek,mt8196-vcp-mbox", .data = &mt8196_cfg },
+ {},
+};
+MODULE_DEVICE_TABLE(of, mtk_vcp_mbox_of_match);
+
+static struct platform_driver mtk_vcp_mbox_driver = {
+ .probe = mtk_vcp_mbox_probe,
+ .driver = {
+ .name = "mtk_vcp_mbox",
+ .of_match_table = mtk_vcp_mbox_of_match,
+ },
+};
+module_platform_driver(mtk_vcp_mbox_driver);
+
+MODULE_AUTHOR("Jjian Zhou <jjian.zhou@mediatek.com>");
+MODULE_DESCRIPTION("MTK VCP Mailbox Controller");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/mailbox/mtk-vcp-mailbox.h b/include/linux/mailbox/mtk-vcp-mailbox.h
new file mode 100644
index 000000000000..143fb0d06e30
--- /dev/null
+++ b/include/linux/mailbox/mtk-vcp-mailbox.h
@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: (GPL-2.0 OR MIT) */
+/*
+ * Copyright (c) 2025 MediaTek Inc.
+ */
+
+#ifndef __MTK_VCP_MAILBOX_H__
+#define __MTK_VCP_MAILBOX_H__
+
+#define MBOX_SLOT_MAX_SIZE 0x100 /* mbox max slot size */
+
+/**
+ * struct mtk_ipi_info - mailbox message info for mtk-vcp-mailbox
+ * @msg: The share buffer between IPC and mailbox driver
+ * @len: Message length
+ * @id: This is for identification purposes and not actually used
+ * by the mailbox hardware.
+ * @index: The signal number of the mailbox message.
+ * @slot_ofs: Data slot offset.
+ * @irq_status: Captures incoming signals for the RX path.
+ *
+ * It is used between IPC with mailbox driver.
+ */
+struct mtk_ipi_info {
+ void *msg;
+ u32 len;
+ u32 id;
+ u32 index;
+ u32 slot_ofs;
+ u32 irq_status;
+};
+
+#endif
--
2.45.2Il 26/09/25 11:05, Jjian Zhou ha scritto:
> Add mtk-vcp-mailbox driver to support the communication with
> VCP remote microprocessor.
>
> Signed-off-by: Jjian Zhou <jjian.zhou@mediatek.com>
> ---
> drivers/mailbox/Kconfig | 9 ++
> drivers/mailbox/Makefile | 2 +
> drivers/mailbox/mtk-vcp-mailbox.c | 168 ++++++++++++++++++++++++
> include/linux/mailbox/mtk-vcp-mailbox.h | 32 +++++
> 4 files changed, 211 insertions(+)
> create mode 100644 drivers/mailbox/mtk-vcp-mailbox.c
> create mode 100644 include/linux/mailbox/mtk-vcp-mailbox.h
>
> diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
> index 02432d4a5ccd..c28bdb855663 100644
> --- a/drivers/mailbox/Kconfig
> +++ b/drivers/mailbox/Kconfig
> @@ -294,6 +294,15 @@ config MTK_CMDQ_MBOX
> critical time limitation, such as updating display configuration
> during the vblank.
>
> +config MTK_VCP_MBOX
> + tristate "MediaTek VCP Mailbox Support"
> + depends on ARCH_MEDIATEK || COMPILE_TEST
> + help
> + Say yes here to add support for the MediaTek VCP mailbox driver.
> + The mailbox implementation provides access from the application
> + processor to Video Companion Processor Unit.
> + If unsure say N.
> +
> config ZYNQMP_IPI_MBOX
> tristate "Xilinx ZynqMP IPI Mailbox"
> depends on ARCH_ZYNQMP && OF
> diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile
> index 98a68f838486..07278871d254 100644
> --- a/drivers/mailbox/Makefile
> +++ b/drivers/mailbox/Makefile
> @@ -63,6 +63,8 @@ obj-$(CONFIG_MTK_ADSP_MBOX) += mtk-adsp-mailbox.o
>
> obj-$(CONFIG_MTK_CMDQ_MBOX) += mtk-cmdq-mailbox.o
>
> +obj-$(CONFIG_MTK_VCP_MBOX) += mtk-vcp-mailbox.o
> +
> obj-$(CONFIG_ZYNQMP_IPI_MBOX) += zynqmp-ipi-mailbox.o
>
> obj-$(CONFIG_SUN6I_MSGBOX) += sun6i-msgbox.o
> diff --git a/drivers/mailbox/mtk-vcp-mailbox.c b/drivers/mailbox/mtk-vcp-mailbox.c
> new file mode 100644
> index 000000000000..a2a80d124e50
> --- /dev/null
> +++ b/drivers/mailbox/mtk-vcp-mailbox.c
> @@ -0,0 +1,168 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2025 MediaTek Corporation. All rights reserved.
> + * Author: Jjian Zhou <jjian.zhou.@mediatek.com>
> + */
> +
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/kernel.h>
> +#include <linux/mailbox_controller.h>
> +#include <linux/mailbox/mtk-vcp-mailbox.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +
> +struct mtk_vcp_mbox {
> + struct mbox_controller mbox;
> + void __iomem *base;
> + struct device *dev;
> + const struct mtk_vcp_mbox_cfg *cfg;
> + struct mtk_ipi_info ipi_recv;
> + struct mbox_chan chans;
> +};
> +
> +struct mtk_vcp_mbox_cfg {
> + u32 set_in;
> + u32 clr_out;
u16 is enough for both register offsets, at least for now - and I suspect it's
going to be enough forever.
> +};
> +
> +static irqreturn_t mtk_vcp_mbox_irq_thread(int irq, void *data)
> +{
> + struct mtk_vcp_mbox *priv = data;
> +
> + /* get irq status */
> + priv->ipi_recv.irq_status = readl(priv->base + priv->cfg->clr_out);
> +
> + __ioread32_copy(priv->ipi_recv.msg, priv->base, MBOX_SLOT_MAX_SIZE / 4);
> +
> + mbox_chan_received_data(&priv->chans, &priv->ipi_recv);
> +
> + /* clear irq status */
> + writel(priv->ipi_recv.irq_status, priv->base + priv->cfg->clr_out);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static struct mbox_chan *mtk_vcp_mbox_xlate(struct mbox_controller *mbox,
> + const struct of_phandle_args *sp)
> +{
> + if (sp->args_count)
> + return NULL;
> +
> + return &mbox->chans[0];
> +}
> +
> +static int mtk_vcp_mbox_send_data(struct mbox_chan *chan, void *data)
> +{
> + struct mtk_vcp_mbox *priv = chan->con_priv;
> + struct mtk_ipi_info *ipi_info = data;
> + u32 status;
> +
> + if (!ipi_info->msg) {
> + dev_err(priv->dev, "msg buffer is NULL.\n");
> + return -EINVAL;
> + }
> +
> + status = readl(priv->base + priv->cfg->set_in) & BIT(ipi_info->index);
status = readl(priv->base + priv->cfg->set_in);
if (status & BIT(ipi_info->index) {
....
}
> + if (status) {
> + dev_warn(priv->dev, "mailbox IPI %d is busy.\n", ipi_info->id);
> + return -EBUSY;
> + }
> +
> + if (ipi_info->slot_ofs + ipi_info->len > MBOX_SLOT_MAX_SIZE)
> + return -EINVAL;
> + __iowrite32_copy(priv->base + ipi_info->slot_ofs, ipi_info->msg,
> + ipi_info->len);
> +
> + writel(BIT(ipi_info->index), priv->base + priv->cfg->set_in);
> +
> + return 0;
> +}
> +
> +static bool mtk_vcp_mbox_last_tx_done(struct mbox_chan *chan)
> +{
> + struct mtk_ipi_info *ipi_info = chan->active_req;
> + struct mtk_vcp_mbox *priv = chan->con_priv;
> +
> + return !(readl(priv->base + priv->cfg->set_in) & BIT(ipi_info->index));
> +}
> +
> +static const struct mbox_chan_ops mtk_vcp_mbox_chan_ops = {
> + .send_data = mtk_vcp_mbox_send_data,
> + .last_tx_done = mtk_vcp_mbox_last_tx_done,
> +};
> +
> +static int mtk_vcp_mbox_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct mtk_vcp_mbox *priv;
> + struct mbox_controller *mbox;
> + int ret, irq;
> +
> + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> + if (!priv)
> + return -ENOMEM;
> +
> + priv->dev = dev;
> + priv->chans.con_priv = priv;
> + mbox = &priv->mbox;
> + mbox->dev = dev;
> + mbox->ops = &mtk_vcp_mbox_chan_ops;
> + mbox->txdone_irq = false;
> + mbox->txdone_poll = true;
> + mbox->of_xlate = mtk_vcp_mbox_xlate;
> + mbox->num_chans = 1;
> + mbox->chans = &priv->chans;
> +
> + priv->ipi_recv.msg = devm_kzalloc(dev, MBOX_SLOT_MAX_SIZE, GFP_KERNEL);
> + if (!priv->ipi_recv.msg)
> + return -ENOMEM;
> +
> + priv->base = devm_platform_ioremap_resource(pdev, 0);
> + if (IS_ERR(priv->base))
> + return PTR_ERR(priv->base);
> +
> + priv->cfg = of_device_get_match_data(dev);
> + if (!priv->cfg)
> + return -EINVAL;
> +
> + irq = platform_get_irq(pdev, 0);
> + if (irq < 0)
> + return irq;
> +
Please set the driver data before requesting the interrupt: what happens if the
ISR is run before having driver data available otherwise?! :-)
> + ret = devm_request_threaded_irq(dev, irq, NULL,
> + mtk_vcp_mbox_irq_thread, IRQF_ONESHOT,
> + dev_name(dev), priv);
> + if (ret < 0)
> + return ret;
> +
> + platform_set_drvdata(pdev, priv);
> +
> + return devm_mbox_controller_register(dev, &priv->mbox);
> +}
> +
> +static const struct mtk_vcp_mbox_cfg mt8196_cfg = {
> + .set_in = 0x100,
> + .clr_out = 0x10c,
> +};
> +
> +static const struct of_device_id mtk_vcp_mbox_of_match[] = {
> + { .compatible = "mediatek,mt8196-vcp-mbox", .data = &mt8196_cfg },
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, mtk_vcp_mbox_of_match);
> +
> +static struct platform_driver mtk_vcp_mbox_driver = {
> + .probe = mtk_vcp_mbox_probe,
> + .driver = {
> + .name = "mtk_vcp_mbox",
> + .of_match_table = mtk_vcp_mbox_of_match,
> + },
> +};
> +module_platform_driver(mtk_vcp_mbox_driver);
> +
> +MODULE_AUTHOR("Jjian Zhou <jjian.zhou@mediatek.com>");
> +MODULE_DESCRIPTION("MTK VCP Mailbox Controller");
> +MODULE_LICENSE("GPL");
> diff --git a/include/linux/mailbox/mtk-vcp-mailbox.h b/include/linux/mailbox/mtk-vcp-mailbox.h
> new file mode 100644
> index 000000000000..143fb0d06e30
> --- /dev/null
> +++ b/include/linux/mailbox/mtk-vcp-mailbox.h
> @@ -0,0 +1,32 @@
> +/* SPDX-License-Identifier: (GPL-2.0 OR MIT) */
> +/*
> + * Copyright (c) 2025 MediaTek Inc.
> + */
> +
> +#ifndef __MTK_VCP_MAILBOX_H__
> +#define __MTK_VCP_MAILBOX_H__
> +
> +#define MBOX_SLOT_MAX_SIZE 0x100 /* mbox max slot size */
Please, change this definition to MTK_VCP_MBOX_SLOT_MAX_SIZE
Cheers,
Angelo
> +
> +/**
> + * struct mtk_ipi_info - mailbox message info for mtk-vcp-mailbox
> + * @msg: The share buffer between IPC and mailbox driver
> + * @len: Message length
> + * @id: This is for identification purposes and not actually used
> + * by the mailbox hardware.
> + * @index: The signal number of the mailbox message.
> + * @slot_ofs: Data slot offset.
> + * @irq_status: Captures incoming signals for the RX path.
> + *
> + * It is used between IPC with mailbox driver.
> + */
> +struct mtk_ipi_info {
> + void *msg;
> + u32 len;
> + u32 id;
> + u32 index;
> + u32 slot_ofs;
> + u32 irq_status;
> +};
> +
> +#endif
On Mon, 2025-09-29 at 12:33 +0200, AngeloGioacchino Del Regno wrote:
> External email : Please do not click links or open attachments until
> you have verified the sender or the content.
>
>
> Il 26/09/25 11:05, Jjian Zhou ha scritto:
> > Add mtk-vcp-mailbox driver to support the communication with
> > VCP remote microprocessor.
> >
> > Signed-off-by: Jjian Zhou <jjian.zhou@mediatek.com>
> > ---
> > drivers/mailbox/Kconfig | 9 ++
> > drivers/mailbox/Makefile | 2 +
> > drivers/mailbox/mtk-vcp-mailbox.c | 168
> > ++++++++++++++++++++++++
> > include/linux/mailbox/mtk-vcp-mailbox.h | 32 +++++
> > 4 files changed, 211 insertions(+)
> > create mode 100644 drivers/mailbox/mtk-vcp-mailbox.c
> > create mode 100644 include/linux/mailbox/mtk-vcp-mailbox.h
> >
> > diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
> > index 02432d4a5ccd..c28bdb855663 100644
> > --- a/drivers/mailbox/Kconfig
> > +++ b/drivers/mailbox/Kconfig
> > @@ -294,6 +294,15 @@ config MTK_CMDQ_MBOX
> > critical time limitation, such as updating display
> > configuration
> > during the vblank.
> >
> > +config MTK_VCP_MBOX
> > + tristate "MediaTek VCP Mailbox Support"
> > + depends on ARCH_MEDIATEK || COMPILE_TEST
> > + help
> > + Say yes here to add support for the MediaTek VCP mailbox
> > driver.
> > + The mailbox implementation provides access from the
> > application
> > + processor to Video Companion Processor Unit.
> > + If unsure say N.
> > +
> > config ZYNQMP_IPI_MBOX
> > tristate "Xilinx ZynqMP IPI Mailbox"
> > depends on ARCH_ZYNQMP && OF
> > diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile
> > index 98a68f838486..07278871d254 100644
> > --- a/drivers/mailbox/Makefile
> > +++ b/drivers/mailbox/Makefile
> > @@ -63,6 +63,8 @@ obj-$(CONFIG_MTK_ADSP_MBOX) += mtk-adsp-mailbox.o
> >
> > obj-$(CONFIG_MTK_CMDQ_MBOX) += mtk-cmdq-mailbox.o
> >
> > +obj-$(CONFIG_MTK_VCP_MBOX) += mtk-vcp-mailbox.o
> > +
> > obj-$(CONFIG_ZYNQMP_IPI_MBOX) += zynqmp-ipi-mailbox.o
> >
> > obj-$(CONFIG_SUN6I_MSGBOX) += sun6i-msgbox.o
> > diff --git a/drivers/mailbox/mtk-vcp-mailbox.c
> > b/drivers/mailbox/mtk-vcp-mailbox.c
> > new file mode 100644
> > index 000000000000..a2a80d124e50
> > --- /dev/null
> > +++ b/drivers/mailbox/mtk-vcp-mailbox.c
> > @@ -0,0 +1,168 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Copyright (c) 2025 MediaTek Corporation. All rights reserved.
> > + * Author: Jjian Zhou <jjian.zhou.@mediatek.com>
> > + */
> > +
> > +#include <linux/interrupt.h>
> > +#include <linux/io.h>
> > +#include <linux/kernel.h>
> > +#include <linux/mailbox_controller.h>
> > +#include <linux/mailbox/mtk-vcp-mailbox.h>
> > +#include <linux/module.h>
> > +#include <linux/of.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/slab.h>
> > +
> > +struct mtk_vcp_mbox {
> > + struct mbox_controller mbox;
> > + void __iomem *base;
> > + struct device *dev;
> > + const struct mtk_vcp_mbox_cfg *cfg;
> > + struct mtk_ipi_info ipi_recv;
> > + struct mbox_chan chans;
> > +};
> > +
> > +struct mtk_vcp_mbox_cfg {
> > + u32 set_in;
> > + u32 clr_out;
>
> u16 is enough for both register offsets, at least for now - and I
> suspect it's
> going to be enough forever.
OK. I change u32 to u16 in the next version.
>
> > +};
> > +
> > +static irqreturn_t mtk_vcp_mbox_irq_thread(int irq, void *data)
> > +{
> > + struct mtk_vcp_mbox *priv = data;
> > +
> > + /* get irq status */
> > + priv->ipi_recv.irq_status = readl(priv->base + priv->cfg-
> > >clr_out);
> > +
> > + __ioread32_copy(priv->ipi_recv.msg, priv->base,
> > MBOX_SLOT_MAX_SIZE / 4);
> > +
> > + mbox_chan_received_data(&priv->chans, &priv->ipi_recv);
> > +
> > + /* clear irq status */
> > + writel(priv->ipi_recv.irq_status, priv->base + priv->cfg-
> > >clr_out);
> > +
> > + return IRQ_HANDLED;
> > +}
> > +
> > +static struct mbox_chan *mtk_vcp_mbox_xlate(struct mbox_controller
> > *mbox,
> > + const struct
> > of_phandle_args *sp)
> > +{
> > + if (sp->args_count)
> > + return NULL;
> > +
> > + return &mbox->chans[0];
> > +}
> > +
> > +static int mtk_vcp_mbox_send_data(struct mbox_chan *chan, void
> > *data)
> > +{
> > + struct mtk_vcp_mbox *priv = chan->con_priv;
> > + struct mtk_ipi_info *ipi_info = data;
> > + u32 status;
> > +
> > + if (!ipi_info->msg) {
> > + dev_err(priv->dev, "msg buffer is NULL.\n");
> > + return -EINVAL;
> > + }
> > +
> > + status = readl(priv->base + priv->cfg->set_in) &
> > BIT(ipi_info->index);
>
> status = readl(priv->base + priv->cfg->set_in);
> if (status & BIT(ipi_info->index) {
> ....
> }
OK.
>
> > + if (status) {
> > + dev_warn(priv->dev, "mailbox IPI %d is busy.\n",
> > ipi_info->id);
> > + return -EBUSY;
> > + }
> > +
> > + if (ipi_info->slot_ofs + ipi_info->len > MBOX_SLOT_MAX_SIZE)
> > + return -EINVAL;
> > + __iowrite32_copy(priv->base + ipi_info->slot_ofs, ipi_info-
> > >msg,
> > + ipi_info->len);
> > +
> > + writel(BIT(ipi_info->index), priv->base + priv->cfg->set_in);
> > +
> > + return 0;
> > +}
> > +
> > +static bool mtk_vcp_mbox_last_tx_done(struct mbox_chan *chan)
> > +{
> > + struct mtk_ipi_info *ipi_info = chan->active_req;
> > + struct mtk_vcp_mbox *priv = chan->con_priv;
> > +
> > + return !(readl(priv->base + priv->cfg->set_in) &
> > BIT(ipi_info->index));
> > +}
> > +
> > +static const struct mbox_chan_ops mtk_vcp_mbox_chan_ops = {
> > + .send_data = mtk_vcp_mbox_send_data,
> > + .last_tx_done = mtk_vcp_mbox_last_tx_done,
> > +};
> > +
> > +static int mtk_vcp_mbox_probe(struct platform_device *pdev)
> > +{
> > + struct device *dev = &pdev->dev;
> > + struct mtk_vcp_mbox *priv;
> > + struct mbox_controller *mbox;
> > + int ret, irq;
> > +
> > + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> > + if (!priv)
> > + return -ENOMEM;
> > +
> > + priv->dev = dev;
> > + priv->chans.con_priv = priv;
> > + mbox = &priv->mbox;
> > + mbox->dev = dev;
> > + mbox->ops = &mtk_vcp_mbox_chan_ops;
> > + mbox->txdone_irq = false;
> > + mbox->txdone_poll = true;
> > + mbox->of_xlate = mtk_vcp_mbox_xlate;
> > + mbox->num_chans = 1;
> > + mbox->chans = &priv->chans;
> > +
> > + priv->ipi_recv.msg = devm_kzalloc(dev, MBOX_SLOT_MAX_SIZE,
> > GFP_KERNEL);
> > + if (!priv->ipi_recv.msg)
> > + return -ENOMEM;
> > +
> > + priv->base = devm_platform_ioremap_resource(pdev, 0);
> > + if (IS_ERR(priv->base))
> > + return PTR_ERR(priv->base);
> > +
> > + priv->cfg = of_device_get_match_data(dev);
> > + if (!priv->cfg)
> > + return -EINVAL;
> > +
> > + irq = platform_get_irq(pdev, 0);
> > + if (irq < 0)
> > + return irq;
> > +
>
> Please set the driver data before requesting the interrupt: what
> happens if the
> ISR is run before having driver data available otherwise?! :-)
>
OK, I put the "platform_set_drvdata(pdev, priv)" between
"of_device_get_match_data(dev)" and "platform_get_irq(pdev, 0)".
Do you want me to submit a new version right now?
> > + ret = devm_request_threaded_irq(dev, irq, NULL,
> > + mtk_vcp_mbox_irq_thread,
> > IRQF_ONESHOT,
> > + dev_name(dev), priv);
> > + if (ret < 0)
> > + return ret;
> > +
> > + platform_set_drvdata(pdev, priv);
> > +
> > + return devm_mbox_controller_register(dev, &priv->mbox);
> > +}
> > +
> > +static const struct mtk_vcp_mbox_cfg mt8196_cfg = {
> > + .set_in = 0x100,
> > + .clr_out = 0x10c,
> > +};
> > +
> > +static const struct of_device_id mtk_vcp_mbox_of_match[] = {
> > + { .compatible = "mediatek,mt8196-vcp-mbox", .data =
> > &mt8196_cfg },
> > + {},
> > +};
> > +MODULE_DEVICE_TABLE(of, mtk_vcp_mbox_of_match);
> > +
> > +static struct platform_driver mtk_vcp_mbox_driver = {
> > + .probe = mtk_vcp_mbox_probe,
> > + .driver = {
> > + .name = "mtk_vcp_mbox",
> > + .of_match_table = mtk_vcp_mbox_of_match,
> > + },
> > +};
> > +module_platform_driver(mtk_vcp_mbox_driver);
> > +
> > +MODULE_AUTHOR("Jjian Zhou <jjian.zhou@mediatek.com>");
> > +MODULE_DESCRIPTION("MTK VCP Mailbox Controller");
> > +MODULE_LICENSE("GPL");
> > diff --git a/include/linux/mailbox/mtk-vcp-mailbox.h
> > b/include/linux/mailbox/mtk-vcp-mailbox.h
> > new file mode 100644
> > index 000000000000..143fb0d06e30
> > --- /dev/null
> > +++ b/include/linux/mailbox/mtk-vcp-mailbox.h
> > @@ -0,0 +1,32 @@
> > +/* SPDX-License-Identifier: (GPL-2.0 OR MIT) */
> > +/*
> > + * Copyright (c) 2025 MediaTek Inc.
> > + */
> > +
> > +#ifndef __MTK_VCP_MAILBOX_H__
> > +#define __MTK_VCP_MAILBOX_H__
> > +
> > +#define MBOX_SLOT_MAX_SIZE 0x100 /* mbox max slot size */
>
> Please, change this definition to MTK_VCP_MBOX_SLOT_MAX_SIZE
OK.
>
> Cheers,
> Angelo
>
> > +
> > +/**
> > + * struct mtk_ipi_info - mailbox message info for mtk-vcp-mailbox
> > + * @msg: The share buffer between IPC and mailbox driver
> > + * @len: Message length
> > + * @id: This is for identification purposes and not actually used
> > + * by the mailbox hardware.
> > + * @index: The signal number of the mailbox message.
> > + * @slot_ofs: Data slot offset.
> > + * @irq_status: Captures incoming signals for the RX path.
> > + *
> > + * It is used between IPC with mailbox driver.
> > + */
> > +struct mtk_ipi_info {
> > + void *msg;
> > + u32 len;
> > + u32 id;
> > + u32 index;
> > + u32 slot_ofs;
> > + u32 irq_status;
> > +};
> > +
> > +#endif
>
>
Il 30/09/25 04:59, Jjian Zhou (周建) ha scritto:
> On Mon, 2025-09-29 at 12:33 +0200, AngeloGioacchino Del Regno wrote:
>> External email : Please do not click links or open attachments until
>> you have verified the sender or the content.
>>
>>
>> Il 26/09/25 11:05, Jjian Zhou ha scritto:
>>> Add mtk-vcp-mailbox driver to support the communication with
>>> VCP remote microprocessor.
>>>
>>> Signed-off-by: Jjian Zhou <jjian.zhou@mediatek.com>
>>> ---
>>> drivers/mailbox/Kconfig | 9 ++
>>> drivers/mailbox/Makefile | 2 +
>>> drivers/mailbox/mtk-vcp-mailbox.c | 168
>>> ++++++++++++++++++++++++
>>> include/linux/mailbox/mtk-vcp-mailbox.h | 32 +++++
>>> 4 files changed, 211 insertions(+)
>>> create mode 100644 drivers/mailbox/mtk-vcp-mailbox.c
>>> create mode 100644 include/linux/mailbox/mtk-vcp-mailbox.h
>>>
>>> diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
>>> index 02432d4a5ccd..c28bdb855663 100644
>>> --- a/drivers/mailbox/Kconfig
>>> +++ b/drivers/mailbox/Kconfig
>>> @@ -294,6 +294,15 @@ config MTK_CMDQ_MBOX
>>> critical time limitation, such as updating display
>>> configuration
>>> during the vblank.
>>>
>>> +config MTK_VCP_MBOX
>>> + tristate "MediaTek VCP Mailbox Support"
>>> + depends on ARCH_MEDIATEK || COMPILE_TEST
>>> + help
>>> + Say yes here to add support for the MediaTek VCP mailbox
>>> driver.
>>> + The mailbox implementation provides access from the
>>> application
>>> + processor to Video Companion Processor Unit.
>>> + If unsure say N.
>>> +
>>> config ZYNQMP_IPI_MBOX
>>> tristate "Xilinx ZynqMP IPI Mailbox"
>>> depends on ARCH_ZYNQMP && OF
>>> diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile
>>> index 98a68f838486..07278871d254 100644
>>> --- a/drivers/mailbox/Makefile
>>> +++ b/drivers/mailbox/Makefile
>>> @@ -63,6 +63,8 @@ obj-$(CONFIG_MTK_ADSP_MBOX) += mtk-adsp-mailbox.o
>>>
>>> obj-$(CONFIG_MTK_CMDQ_MBOX) += mtk-cmdq-mailbox.o
>>>
>>> +obj-$(CONFIG_MTK_VCP_MBOX) += mtk-vcp-mailbox.o
>>> +
>>> obj-$(CONFIG_ZYNQMP_IPI_MBOX) += zynqmp-ipi-mailbox.o
>>>
>>> obj-$(CONFIG_SUN6I_MSGBOX) += sun6i-msgbox.o
>>> diff --git a/drivers/mailbox/mtk-vcp-mailbox.c
>>> b/drivers/mailbox/mtk-vcp-mailbox.c
>>> new file mode 100644
>>> index 000000000000..a2a80d124e50
>>> --- /dev/null
>>> +++ b/drivers/mailbox/mtk-vcp-mailbox.c
>>> @@ -0,0 +1,168 @@
>>> +// SPDX-License-Identifier: GPL-2.0
>>> +/*
>>> + * Copyright (c) 2025 MediaTek Corporation. All rights reserved.
>>> + * Author: Jjian Zhou <jjian.zhou.@mediatek.com>
>>> + */
>>> +
>>> +#include <linux/interrupt.h>
>>> +#include <linux/io.h>
>>> +#include <linux/kernel.h>
>>> +#include <linux/mailbox_controller.h>
>>> +#include <linux/mailbox/mtk-vcp-mailbox.h>
>>> +#include <linux/module.h>
>>> +#include <linux/of.h>
>>> +#include <linux/platform_device.h>
>>> +#include <linux/slab.h>
>>> +
>>> +struct mtk_vcp_mbox {
>>> + struct mbox_controller mbox;
>>> + void __iomem *base;
>>> + struct device *dev;
>>> + const struct mtk_vcp_mbox_cfg *cfg;
>>> + struct mtk_ipi_info ipi_recv;
>>> + struct mbox_chan chans;
>>> +};
>>> +
>>> +struct mtk_vcp_mbox_cfg {
>>> + u32 set_in;
>>> + u32 clr_out;
>>
>> u16 is enough for both register offsets, at least for now - and I
>> suspect it's
>> going to be enough forever.
>
> OK. I change u32 to u16 in the next version.
>
>>
>>> +};
>>> +
>>> +static irqreturn_t mtk_vcp_mbox_irq_thread(int irq, void *data)
>>> +{
>>> + struct mtk_vcp_mbox *priv = data;
>>> +
>>> + /* get irq status */
>>> + priv->ipi_recv.irq_status = readl(priv->base + priv->cfg-
>>>> clr_out);
>>> +
>>> + __ioread32_copy(priv->ipi_recv.msg, priv->base,
>>> MBOX_SLOT_MAX_SIZE / 4);
>>> +
>>> + mbox_chan_received_data(&priv->chans, &priv->ipi_recv);
>>> +
>>> + /* clear irq status */
>>> + writel(priv->ipi_recv.irq_status, priv->base + priv->cfg-
>>>> clr_out);
>>> +
>>> + return IRQ_HANDLED;
>>> +}
>>> +
>>> +static struct mbox_chan *mtk_vcp_mbox_xlate(struct mbox_controller
>>> *mbox,
>>> + const struct
>>> of_phandle_args *sp)
>>> +{
>>> + if (sp->args_count)
>>> + return NULL;
>>> +
>>> + return &mbox->chans[0];
>>> +}
>>> +
>>> +static int mtk_vcp_mbox_send_data(struct mbox_chan *chan, void
>>> *data)
>>> +{
>>> + struct mtk_vcp_mbox *priv = chan->con_priv;
>>> + struct mtk_ipi_info *ipi_info = data;
>>> + u32 status;
>>> +
>>> + if (!ipi_info->msg) {
>>> + dev_err(priv->dev, "msg buffer is NULL.\n");
>>> + return -EINVAL;
>>> + }
>>> +
>>> + status = readl(priv->base + priv->cfg->set_in) &
>>> BIT(ipi_info->index);
>>
>> status = readl(priv->base + priv->cfg->set_in);
>> if (status & BIT(ipi_info->index) {
>> ....
>> }
>
> OK.
>
>>
>>> + if (status) {
>>> + dev_warn(priv->dev, "mailbox IPI %d is busy.\n",
>>> ipi_info->id);
>>> + return -EBUSY;
>>> + }
>>> +
>>> + if (ipi_info->slot_ofs + ipi_info->len > MBOX_SLOT_MAX_SIZE)
>>> + return -EINVAL;
>>> + __iowrite32_copy(priv->base + ipi_info->slot_ofs, ipi_info-
>>>> msg,
>>> + ipi_info->len);
>>> +
>>> + writel(BIT(ipi_info->index), priv->base + priv->cfg->set_in);
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +static bool mtk_vcp_mbox_last_tx_done(struct mbox_chan *chan)
>>> +{
>>> + struct mtk_ipi_info *ipi_info = chan->active_req;
>>> + struct mtk_vcp_mbox *priv = chan->con_priv;
>>> +
>>> + return !(readl(priv->base + priv->cfg->set_in) &
>>> BIT(ipi_info->index));
>>> +}
>>> +
>>> +static const struct mbox_chan_ops mtk_vcp_mbox_chan_ops = {
>>> + .send_data = mtk_vcp_mbox_send_data,
>>> + .last_tx_done = mtk_vcp_mbox_last_tx_done,
>>> +};
>>> +
>>> +static int mtk_vcp_mbox_probe(struct platform_device *pdev)
>>> +{
>>> + struct device *dev = &pdev->dev;
>>> + struct mtk_vcp_mbox *priv;
>>> + struct mbox_controller *mbox;
>>> + int ret, irq;
>>> +
>>> + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
>>> + if (!priv)
>>> + return -ENOMEM;
>>> +
>>> + priv->dev = dev;
>>> + priv->chans.con_priv = priv;
>>> + mbox = &priv->mbox;
>>> + mbox->dev = dev;
>>> + mbox->ops = &mtk_vcp_mbox_chan_ops;
>>> + mbox->txdone_irq = false;
>>> + mbox->txdone_poll = true;
>>> + mbox->of_xlate = mtk_vcp_mbox_xlate;
>>> + mbox->num_chans = 1;
>>> + mbox->chans = &priv->chans;
>>> +
>>> + priv->ipi_recv.msg = devm_kzalloc(dev, MBOX_SLOT_MAX_SIZE,
>>> GFP_KERNEL);
>>> + if (!priv->ipi_recv.msg)
>>> + return -ENOMEM;
>>> +
>>> + priv->base = devm_platform_ioremap_resource(pdev, 0);
>>> + if (IS_ERR(priv->base))
>>> + return PTR_ERR(priv->base);
>>> +
>>> + priv->cfg = of_device_get_match_data(dev);
>>> + if (!priv->cfg)
>>> + return -EINVAL;
>>> +
>>> + irq = platform_get_irq(pdev, 0);
>>> + if (irq < 0)
>>> + return irq;
>>> +
>>
>> Please set the driver data before requesting the interrupt: what
>> happens if the
>> ISR is run before having driver data available otherwise?! :-)
>>
>
> OK, I put the "platform_set_drvdata(pdev, priv)" between
> "of_device_get_match_data(dev)" and "platform_get_irq(pdev, 0)".
>
> Do you want me to submit a new version right now?
Yes, please.
Cheers,
Angelo
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