On Wed, Jun 12, 2024 at 06:10:53PM GMT, Sibi Sankar wrote:
> Add support for CPUSS Control Processor (CPUCP) mailbox controller,
> this driver enables communication between AP and CPUCP by acting as
> a doorbell between them.
>
> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
> Signed-off-by: Sibi Sankar <quic_sibis@xxxxxxxxxxx>
Reviewed-by: Bjorn Andersson <andersson@xxxxxxxxxx>
Regards,
Bjorn
> ---
>
> v5:
> * Fix build error reported by kernel test robot by adding 64BIT requirement
> to COMPILE_TEST
>
> MAINTAINERS | 7 ++
> drivers/mailbox/Kconfig | 8 ++
> drivers/mailbox/Makefile | 2 +
> drivers/mailbox/qcom-cpucp-mbox.c | 187 ++++++++++++++++++++++++++++++
> 4 files changed, 204 insertions(+)
> create mode 100644 drivers/mailbox/qcom-cpucp-mbox.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index e04f583780c5..d7c00abe2f93 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -18533,6 +18533,13 @@ S: Maintained
> F: Documentation/devicetree/bindings/power/avs/qcom,cpr.yaml
> F: drivers/pmdomain/qcom/cpr.c
>
> +QUALCOMM CPUCP MAILBOX DRIVER
> +M: Sibi Sankar <quic_sibis@xxxxxxxxxxx>
> +L: linux-arm-msm@xxxxxxxxxxxxxxx
> +S: Supported
> +F: Documentation/devicetree/bindings/mailbox/qcom,cpucp-mbox.yaml
> +F: drivers/mailbox/qcom-cpucp-mbox.c
> +
> QUALCOMM CPUFREQ DRIVER MSM8996/APQ8096
> M: Ilia Lin <ilia.lin@xxxxxxxxxx>
> L: linux-pm@xxxxxxxxxxxxxxx
> diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
> index 3b8842c4a340..d1f6c758b5e8 100644
> --- a/drivers/mailbox/Kconfig
> +++ b/drivers/mailbox/Kconfig
> @@ -276,6 +276,14 @@ config SPRD_MBOX
> to send message between application processors and MCU. Say Y here if
> you want to build the Spreatrum mailbox controller driver.
>
> +config QCOM_CPUCP_MBOX
> + tristate "Qualcomm Technologies, Inc. CPUCP mailbox driver"
> + depends on ARCH_QCOM || (COMPILE_TEST && 64BIT)
> + help
> + Qualcomm Technologies, Inc. CPUSS Control Processor (CPUCP) mailbox
> + controller driver enables communication between AP and CPUCP. Say
> + Y here if you want to build this driver.
> +
> config QCOM_IPCC
> tristate "Qualcomm Technologies, Inc. IPCC driver"
> depends on ARCH_QCOM || COMPILE_TEST
> diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile
> index 5cf2f54debaf..3c3c27d54c13 100644
> --- a/drivers/mailbox/Makefile
> +++ b/drivers/mailbox/Makefile
> @@ -61,4 +61,6 @@ obj-$(CONFIG_SUN6I_MSGBOX) += sun6i-msgbox.o
>
> obj-$(CONFIG_SPRD_MBOX) += sprd-mailbox.o
>
> +obj-$(CONFIG_QCOM_CPUCP_MBOX) += qcom-cpucp-mbox.o
> +
> obj-$(CONFIG_QCOM_IPCC) += qcom-ipcc.o
> diff --git a/drivers/mailbox/qcom-cpucp-mbox.c b/drivers/mailbox/qcom-cpucp-mbox.c
> new file mode 100644
> index 000000000000..e5437c294803
> --- /dev/null
> +++ b/drivers/mailbox/qcom-cpucp-mbox.c
> @@ -0,0 +1,187 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (c) 2024, Qualcomm Innovation Center, Inc. All rights reserved.
> + */
> +
> +#include <linux/bitops.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/irq.h>
> +#include <linux/irqdomain.h>
> +#include <linux/mailbox_controller.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +
> +#define APSS_CPUCP_IPC_CHAN_SUPPORTED 3
> +#define APSS_CPUCP_MBOX_CMD_OFF 0x4
> +
> +/* Tx Registers */
> +#define APSS_CPUCP_TX_MBOX_CMD(i) (0x100 + ((i) * 8))
> +
> +/* Rx Registers */
> +#define APSS_CPUCP_RX_MBOX_CMD(i) (0x100 + ((i) * 8))
> +#define APSS_CPUCP_RX_MBOX_MAP 0x4000
> +#define APSS_CPUCP_RX_MBOX_STAT 0x4400
> +#define APSS_CPUCP_RX_MBOX_CLEAR 0x4800
> +#define APSS_CPUCP_RX_MBOX_EN 0x4c00
> +#define APSS_CPUCP_RX_MBOX_CMD_MASK GENMASK_ULL(63, 0)
> +
> +/**
> + * struct qcom_cpucp_mbox - Holder for the mailbox driver
> + * @chans: The mailbox channel
> + * @mbox: The mailbox controller
> + * @tx_base: Base address of the CPUCP tx registers
> + * @rx_base: Base address of the CPUCP rx registers
> + */
> +struct qcom_cpucp_mbox {
> + struct mbox_chan chans[APSS_CPUCP_IPC_CHAN_SUPPORTED];
> + struct mbox_controller mbox;
> + void __iomem *tx_base;
> + void __iomem *rx_base;
> +};
> +
> +static inline int channel_number(struct mbox_chan *chan)
> +{
> + return chan - chan->mbox->chans;
> +}
> +
> +static irqreturn_t qcom_cpucp_mbox_irq_fn(int irq, void *data)
> +{
> + struct qcom_cpucp_mbox *cpucp = data;
> + u64 status;
> + int i;
> +
> + status = readq(cpucp->rx_base + APSS_CPUCP_RX_MBOX_STAT);
> +
> + for_each_set_bit(i, (unsigned long *)&status, APSS_CPUCP_IPC_CHAN_SUPPORTED) {
> + u32 val = readl(cpucp->rx_base + APSS_CPUCP_RX_MBOX_CMD(i) + APSS_CPUCP_MBOX_CMD_OFF);
> + struct mbox_chan *chan = &cpucp->chans[i];
> + unsigned long flags;
> +
> + /* Provide mutual exclusion with changes to chan->cl */
> + spin_lock_irqsave(&chan->lock, flags);
> + if (chan->cl)
> + mbox_chan_received_data(chan, &val);
> + writeq(BIT(i), cpucp->rx_base + APSS_CPUCP_RX_MBOX_CLEAR);
> + spin_unlock_irqrestore(&chan->lock, flags);
> + }
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int qcom_cpucp_mbox_startup(struct mbox_chan *chan)
> +{
> + struct qcom_cpucp_mbox *cpucp = container_of(chan->mbox, struct qcom_cpucp_mbox, mbox);
> + unsigned long chan_id = channel_number(chan);
> + u64 val;
> +
> + val = readq(cpucp->rx_base + APSS_CPUCP_RX_MBOX_EN);
> + val |= BIT(chan_id);
> + writeq(val, cpucp->rx_base + APSS_CPUCP_RX_MBOX_EN);
> +
> + return 0;
> +}
> +
> +static void qcom_cpucp_mbox_shutdown(struct mbox_chan *chan)
> +{
> + struct qcom_cpucp_mbox *cpucp = container_of(chan->mbox, struct qcom_cpucp_mbox, mbox);
> + unsigned long chan_id = channel_number(chan);
> + u64 val;
> +
> + val = readq(cpucp->rx_base + APSS_CPUCP_RX_MBOX_EN);
> + val &= ~BIT(chan_id);
> + writeq(val, cpucp->rx_base + APSS_CPUCP_RX_MBOX_EN);
> +}
> +
> +static int qcom_cpucp_mbox_send_data(struct mbox_chan *chan, void *data)
> +{
> + struct qcom_cpucp_mbox *cpucp = container_of(chan->mbox, struct qcom_cpucp_mbox, mbox);
> + unsigned long chan_id = channel_number(chan);
> + u32 *val = data;
> +
> + writel(*val, cpucp->tx_base + APSS_CPUCP_TX_MBOX_CMD(chan_id) + APSS_CPUCP_MBOX_CMD_OFF);
> +
> + return 0;
> +}
> +
> +static const struct mbox_chan_ops qcom_cpucp_mbox_chan_ops = {
> + .startup = qcom_cpucp_mbox_startup,
> + .send_data = qcom_cpucp_mbox_send_data,
> + .shutdown = qcom_cpucp_mbox_shutdown
> +};
> +
> +static int qcom_cpucp_mbox_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct qcom_cpucp_mbox *cpucp;
> + struct mbox_controller *mbox;
> + int irq, ret;
> +
> + cpucp = devm_kzalloc(dev, sizeof(*cpucp), GFP_KERNEL);
> + if (!cpucp)
> + return -ENOMEM;
> +
> + cpucp->rx_base = devm_of_iomap(dev, dev->of_node, 0, NULL);
> + if (IS_ERR(cpucp->rx_base))
> + return PTR_ERR(cpucp->rx_base);
> +
> + cpucp->tx_base = devm_of_iomap(dev, dev->of_node, 1, NULL);
> + if (IS_ERR(cpucp->tx_base))
> + return PTR_ERR(cpucp->tx_base);
> +
> + writeq(0, cpucp->rx_base + APSS_CPUCP_RX_MBOX_EN);
> + writeq(0, cpucp->rx_base + APSS_CPUCP_RX_MBOX_CLEAR);
> + writeq(0, cpucp->rx_base + APSS_CPUCP_RX_MBOX_MAP);
> +
> + irq = platform_get_irq(pdev, 0);
> + if (irq < 0)
> + return irq;
> +
> + ret = devm_request_irq(dev, irq, qcom_cpucp_mbox_irq_fn,
> + IRQF_TRIGGER_HIGH, "apss_cpucp_mbox", cpucp);
> + if (ret < 0)
> + return dev_err_probe(dev, ret, "Failed to register irq: %d\n", irq);
> +
> + writeq(APSS_CPUCP_RX_MBOX_CMD_MASK, cpucp->rx_base + APSS_CPUCP_RX_MBOX_MAP);
> +
> + mbox = &cpucp->mbox;
> + mbox->dev = dev;
> + mbox->num_chans = APSS_CPUCP_IPC_CHAN_SUPPORTED;
> + mbox->chans = cpucp->chans;
> + mbox->ops = &qcom_cpucp_mbox_chan_ops;
> +
> + ret = devm_mbox_controller_register(dev, mbox);
> + if (ret)
> + return dev_err_probe(dev, ret, "Failed to create mailbox\n");
> +
> + return 0;
> +}
> +
> +static const struct of_device_id qcom_cpucp_mbox_of_match[] = {
> + { .compatible = "qcom,x1e80100-cpucp-mbox" },
> + {}
> +};
> +MODULE_DEVICE_TABLE(of, qcom_cpucp_mbox_of_match);
> +
> +static struct platform_driver qcom_cpucp_mbox_driver = {
> + .probe = qcom_cpucp_mbox_probe,
> + .driver = {
> + .name = "qcom_cpucp_mbox",
> + .of_match_table = qcom_cpucp_mbox_of_match,
> + },
> +};
> +
> +static int __init qcom_cpucp_mbox_init(void)
> +{
> + return platform_driver_register(&qcom_cpucp_mbox_driver);
> +}
> +core_initcall(qcom_cpucp_mbox_init);
> +
> +static void __exit qcom_cpucp_mbox_exit(void)
> +{
> + platform_driver_unregister(&qcom_cpucp_mbox_driver);
> +}
> +module_exit(qcom_cpucp_mbox_exit);
> +
> +MODULE_DESCRIPTION("QTI CPUCP MBOX Driver");
> +MODULE_LICENSE("GPL");
> --
> 2.34.1
>
