1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2022 MediaTek Corporation. All rights reserved.
4 * Author: Allen-KH Cheng <allen-kh.cheng@mediatek.com>
5 */
6
7#include <linux/interrupt.h>
8#include <linux/io.h>
9#include <linux/iopoll.h>
10#include <linux/kernel.h>
11#include <linux/mailbox_controller.h>
12#include <linux/module.h>
13#include <linux/of.h>
14#include <linux/platform_device.h>
15#include <linux/slab.h>
16
17struct mtk_adsp_mbox_priv {
18	struct device *dev;
19	struct mbox_controller mbox;
20	void __iomem *va_mboxreg;
21	const struct mtk_adsp_mbox_cfg *cfg;
22};
23
24struct mtk_adsp_mbox_cfg {
25	u32 set_in;
26	u32 set_out;
27	u32 clr_in;
28	u32 clr_out;
29};
30
31static inline struct mtk_adsp_mbox_priv *get_mtk_adsp_mbox_priv(struct mbox_controller *mbox)
32{
33	return container_of(mbox, struct mtk_adsp_mbox_priv, mbox);
34}
35
36static irqreturn_t mtk_adsp_mbox_irq(int irq, void *data)
37{
38	struct mbox_chan *chan = data;
39	struct mtk_adsp_mbox_priv *priv = get_mtk_adsp_mbox_priv(chan->mbox);
40	u32 op = readl(priv->va_mboxreg + priv->cfg->set_out);
41
42	writel(op, priv->va_mboxreg + priv->cfg->clr_out);
43
44	return IRQ_WAKE_THREAD;
45}
46
47static irqreturn_t mtk_adsp_mbox_isr(int irq, void *data)
48{
49	struct mbox_chan *chan = data;
50
51	mbox_chan_received_data(chan, NULL);
52
53	return IRQ_HANDLED;
54}
55
56static struct mbox_chan *mtk_adsp_mbox_xlate(struct mbox_controller *mbox,
57					     const struct of_phandle_args *sp)
58{
59	return mbox->chans;
60}
61
62static int mtk_adsp_mbox_startup(struct mbox_chan *chan)
63{
64	struct mtk_adsp_mbox_priv *priv = get_mtk_adsp_mbox_priv(chan->mbox);
65
66	/* Clear ADSP mbox command */
67	writel(0xFFFFFFFF, priv->va_mboxreg + priv->cfg->clr_in);
68	writel(0xFFFFFFFF, priv->va_mboxreg + priv->cfg->clr_out);
69
70	return 0;
71}
72
73static void mtk_adsp_mbox_shutdown(struct mbox_chan *chan)
74{
75	struct mtk_adsp_mbox_priv *priv = get_mtk_adsp_mbox_priv(chan->mbox);
76
77	/* Clear ADSP mbox command */
78	writel(0xFFFFFFFF, priv->va_mboxreg + priv->cfg->clr_in);
79	writel(0xFFFFFFFF, priv->va_mboxreg + priv->cfg->clr_out);
80}
81
82static int mtk_adsp_mbox_send_data(struct mbox_chan *chan, void *data)
83{
84	struct mtk_adsp_mbox_priv *priv = get_mtk_adsp_mbox_priv(chan->mbox);
85	u32 *msg = data;
86
87	writel(*msg, priv->va_mboxreg + priv->cfg->set_in);
88
89	return 0;
90}
91
92static bool mtk_adsp_mbox_last_tx_done(struct mbox_chan *chan)
93{
94	struct mtk_adsp_mbox_priv *priv = get_mtk_adsp_mbox_priv(chan->mbox);
95
96	return readl(priv->va_mboxreg + priv->cfg->set_in) == 0;
97}
98
99static const struct mbox_chan_ops mtk_adsp_mbox_chan_ops = {
100	.send_data	= mtk_adsp_mbox_send_data,
101	.startup	= mtk_adsp_mbox_startup,
102	.shutdown	= mtk_adsp_mbox_shutdown,
103	.last_tx_done	= mtk_adsp_mbox_last_tx_done,
104};
105
106static int mtk_adsp_mbox_probe(struct platform_device *pdev)
107{
108	struct device *dev = &pdev->dev;
109	struct mtk_adsp_mbox_priv *priv;
110	const struct mtk_adsp_mbox_cfg *cfg;
111	struct mbox_controller *mbox;
112	int ret, irq;
113
114	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
115	if (!priv)
116		return -ENOMEM;
117
118	mbox = &priv->mbox;
119	mbox->dev = dev;
120	mbox->ops = &mtk_adsp_mbox_chan_ops;
121	mbox->txdone_irq = false;
122	mbox->txdone_poll = true;
123	mbox->of_xlate = mtk_adsp_mbox_xlate;
124	mbox->num_chans = 1;
125	mbox->chans = devm_kzalloc(dev, sizeof(*mbox->chans), GFP_KERNEL);
126	if (!mbox->chans)
127		return -ENOMEM;
128
129	priv->va_mboxreg = devm_platform_ioremap_resource(pdev, 0);
130	if (IS_ERR(priv->va_mboxreg))
131		return PTR_ERR(priv->va_mboxreg);
132
133	cfg = of_device_get_match_data(dev);
134	if (!cfg)
135		return -EINVAL;
136	priv->cfg = cfg;
137
138	irq = platform_get_irq(pdev, 0);
139	if (irq < 0)
140		return irq;
141
142	ret = devm_request_threaded_irq(dev, irq, mtk_adsp_mbox_irq,
143					mtk_adsp_mbox_isr, IRQF_TRIGGER_NONE,
144					dev_name(dev), mbox->chans);
145	if (ret < 0)
146		return ret;
147
148	platform_set_drvdata(pdev, priv);
149
150	return devm_mbox_controller_register(dev, &priv->mbox);
151}
152
153static const struct mtk_adsp_mbox_cfg mt8186_adsp_mbox_cfg = {
154	.set_in		= 0x00,
155	.set_out	= 0x04,
156	.clr_in		= 0x08,
157	.clr_out	= 0x0C,
158};
159
160static const struct mtk_adsp_mbox_cfg mt8195_adsp_mbox_cfg = {
161	.set_in		= 0x00,
162	.set_out	= 0x1c,
163	.clr_in		= 0x04,
164	.clr_out	= 0x20,
165};
166
167static const struct of_device_id mtk_adsp_mbox_of_match[] = {
168	{ .compatible = "mediatek,mt8186-adsp-mbox", .data = &mt8186_adsp_mbox_cfg },
169	{ .compatible = "mediatek,mt8195-adsp-mbox", .data = &mt8195_adsp_mbox_cfg },
170	{},
171};
172MODULE_DEVICE_TABLE(of, mtk_adsp_mbox_of_match);
173
174static struct platform_driver mtk_adsp_mbox_driver = {
175	.probe		= mtk_adsp_mbox_probe,
176	.driver = {
177		.name	= "mtk_adsp_mbox",
178		.of_match_table = mtk_adsp_mbox_of_match,
179	},
180};
181module_platform_driver(mtk_adsp_mbox_driver);
182
183MODULE_AUTHOR("Allen-KH Cheng <Allen-KH.Cheng@mediatek.com>");
184MODULE_DESCRIPTION("MTK ADSP Mailbox Controller");
185MODULE_LICENSE("GPL v2");
186