This implements a driver that exposes the IPC bits found in the APCS Global block in various Qualcomm platforms. The bits are used to signal inter-processor communication signals from the application CPU to other masters.
The driver implements the "doorbell" binding and could be used as basis for a new Linux framework, if found useful outside Qualcomm. Signed-off-by: Bjorn Andersson <bjorn.anders...@linaro.org> --- Changes since v3: - Migrate to mailbox framework Changes since v2: - New driver drivers/mailbox/Kconfig | 8 ++ drivers/mailbox/Makefile | 2 + drivers/mailbox/qcom-apcs-ipc-mailbox.c | 128 ++++++++++++++++++++++++++++++++ 3 files changed, 138 insertions(+) create mode 100644 drivers/mailbox/qcom-apcs-ipc-mailbox.c diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig index ceff415f201c..fffc64da61f9 100644 --- a/drivers/mailbox/Kconfig +++ b/drivers/mailbox/Kconfig @@ -124,6 +124,14 @@ config MAILBOX_TEST Test client to help with testing new Controller driver implementations. +config QCOM_APCS_IPC + tristate "Qualcomm APCS IPC driver" + depends on ARCH_QCOM + help + Say y here to enable support for the APCS IPC doorbell driver, + providing an interface for invoking the inter-process communication + signals from the application processor to other masters. + config TEGRA_HSP_MBOX bool "Tegra HSP (Hardware Synchronization Primitives) Driver" depends on ARCH_TEGRA_186_SOC diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile index 7dde4f609ae8..cc718c79669a 100644 --- a/drivers/mailbox/Makefile +++ b/drivers/mailbox/Makefile @@ -30,4 +30,6 @@ obj-$(CONFIG_HI6220_MBOX) += hi6220-mailbox.o obj-$(CONFIG_BCM_PDC_MBOX) += bcm-pdc-mailbox.o +obj-$(CONFIG_QCOM_APCS_IPC) += qcom-apcs-ipc-mailbox.o + obj-$(CONFIG_TEGRA_HSP_MBOX) += tegra-hsp.o diff --git a/drivers/mailbox/qcom-apcs-ipc-mailbox.c b/drivers/mailbox/qcom-apcs-ipc-mailbox.c new file mode 100644 index 000000000000..41e31c66c7aa --- /dev/null +++ b/drivers/mailbox/qcom-apcs-ipc-mailbox.c @@ -0,0 +1,128 @@ +/* + * Copyright (c) 2017, Linaro Ltd + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/io.h> +#include <linux/slab.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/mailbox_controller.h> + +#define QCOM_APCS_IPC_BITS 32 + +struct qcom_apcs_ipc { + struct device *dev; + + struct mbox_controller mbox; + struct mbox_chan mbox_chans[QCOM_APCS_IPC_BITS]; + + void __iomem *base; + unsigned long offset; +}; + +static int qcom_apcs_ipc_send_data(struct mbox_chan *chan, void *data) +{ + struct qcom_apcs_ipc *apcs = container_of(chan->mbox, + struct qcom_apcs_ipc, mbox); + unsigned long idx = (unsigned long)chan->con_priv; + + writel(BIT(idx), apcs->base + apcs->offset); + + return 0; +} + +static const struct mbox_chan_ops qcom_apcs_ipc_ops = { + .send_data = qcom_apcs_ipc_send_data, +}; + +static int qcom_apcs_ipc_probe(struct platform_device *pdev) +{ + struct qcom_apcs_ipc *apcs; + struct resource *res; + unsigned long i; + int ret; + + apcs = devm_kzalloc(&pdev->dev, sizeof(*apcs), GFP_KERNEL); + if (!apcs) + return -ENOMEM; + + apcs->dev = &pdev->dev; + apcs->offset = (unsigned long)of_device_get_match_data(&pdev->dev); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + apcs->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(apcs->base)) + return PTR_ERR(apcs->base); + + /* Initialize channel identifiers */ + for (i = 0; i < ARRAY_SIZE(apcs->mbox_chans); i++) + apcs->mbox_chans[i].con_priv = (void *)i; + + apcs->mbox.dev = &pdev->dev; + apcs->mbox.ops = &qcom_apcs_ipc_ops; + apcs->mbox.chans = apcs->mbox_chans; + apcs->mbox.num_chans = ARRAY_SIZE(apcs->mbox_chans); + + ret = mbox_controller_register(&apcs->mbox); + if (ret) { + dev_err(&pdev->dev, "failed to register APCS IPC controller\n"); + return ret; + } + + platform_set_drvdata(pdev, apcs); + + return 0; +} + +static int qcom_apcs_ipc_remove(struct platform_device *pdev) +{ + struct qcom_apcs_ipc *apcs = platform_get_drvdata(pdev); + + mbox_controller_unregister(&apcs->mbox); + + return 0; +} + +/* .data is the offset of the ipc register within the global block */ +static const struct of_device_id qcom_apcs_ipc_of_match[] = { + { .compatible = "qcom,msm8916-apcs-kpss-global", .data = (void *)8 }, + { .compatible = "qcom,msm8996-apcs-hmss-global", .data = (void *)16 }, + {} +}; +MODULE_DEVICE_TABLE(of, qcom_apcs_ipc_of_match); + +static struct platform_driver qcom_apcs_ipc_driver = { + .probe = qcom_apcs_ipc_probe, + .remove = qcom_apcs_ipc_remove, + .driver = { + .name = "qcom_apcs_ipc", + .of_match_table = qcom_apcs_ipc_of_match, + }, +}; + +static int __init qcom_apcs_ipc_init(void) +{ + return platform_driver_register(&qcom_apcs_ipc_driver); +} +postcore_initcall(qcom_apcs_ipc_init); + +static void __exit qcom_apcs_ipc_exit(void) +{ + platform_driver_unregister(&qcom_apcs_ipc_driver); +} +module_exit(qcom_apcs_ipc_exit); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("Qualcomm APCS IPC driver"); -- 2.12.0