linux_dsm_epyc7002/drivers/mailbox/qcom-apcs-ipc-mailbox.c
Bjorn Andersson 25bfee16d5 mailbox: Introduce Qualcomm APCS IPC driver
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.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
2017-06-14 17:47:19 +05:30

130 lines
3.3 KiB
C

/*
* 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 mbox_controller mbox;
struct mbox_chan mbox_chans[QCOM_APCS_IPC_BITS];
void __iomem *reg;
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->reg);
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 offset;
void __iomem *base;
unsigned long i;
int ret;
apcs = devm_kzalloc(&pdev->dev, sizeof(*apcs), GFP_KERNEL);
if (!apcs)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(base))
return PTR_ERR(base);
offset = (unsigned long)of_device_get_match_data(&pdev->dev);
apcs->reg = base + offset;
/* 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");