1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2018, NVIDIA CORPORATION.
4 */
5
6#include <linux/interrupt.h>
7#include <linux/irq.h>
8#include <linux/io.h>
9#include <linux/of.h>
10#include <linux/platform_device.h>
11
12#include <soc/tegra/bpmp.h>
13
14#include "bpmp-private.h"
15
16#define TRIGGER_OFFSET		0x000
17#define RESULT_OFFSET(id)	(0xc00 + id * 4)
18#define TRIGGER_ID_SHIFT	16
19#define TRIGGER_CMD_GET		4
20
21#define STA_OFFSET		0
22#define SET_OFFSET		4
23#define CLR_OFFSET		8
24
25#define CH_MASK(ch)	(0x3 << ((ch) * 2))
26#define SL_SIGL(ch)	(0x0 << ((ch) * 2))
27#define SL_QUED(ch)	(0x1 << ((ch) * 2))
28#define MA_FREE(ch)	(0x2 << ((ch) * 2))
29#define MA_ACKD(ch)	(0x3 << ((ch) * 2))
30
31struct tegra210_bpmp {
32	void __iomem *atomics;
33	void __iomem *arb_sema;
34	struct irq_data *tx_irq_data;
35};
36
37static u32 bpmp_channel_status(struct tegra_bpmp *bpmp, unsigned int index)
38{
39	struct tegra210_bpmp *priv = bpmp->priv;
40
41	return __raw_readl(priv->arb_sema + STA_OFFSET) & CH_MASK(index);
42}
43
44static bool tegra210_bpmp_is_response_ready(struct tegra_bpmp_channel *channel)
45{
46	unsigned int index = channel->index;
47
48	return bpmp_channel_status(channel->bpmp, index) == MA_ACKD(index);
49}
50
51static bool tegra210_bpmp_is_request_ready(struct tegra_bpmp_channel *channel)
52{
53	unsigned int index = channel->index;
54
55	return bpmp_channel_status(channel->bpmp, index) == SL_SIGL(index);
56}
57
58static bool
59tegra210_bpmp_is_request_channel_free(struct tegra_bpmp_channel *channel)
60{
61	unsigned int index = channel->index;
62
63	return bpmp_channel_status(channel->bpmp, index) == MA_FREE(index);
64}
65
66static bool
67tegra210_bpmp_is_response_channel_free(struct tegra_bpmp_channel *channel)
68{
69	unsigned int index = channel->index;
70
71	return bpmp_channel_status(channel->bpmp, index) == SL_QUED(index);
72}
73
74static int tegra210_bpmp_post_request(struct tegra_bpmp_channel *channel)
75{
76	struct tegra210_bpmp *priv = channel->bpmp->priv;
77
78	__raw_writel(CH_MASK(channel->index), priv->arb_sema + CLR_OFFSET);
79
80	return 0;
81}
82
83static int tegra210_bpmp_post_response(struct tegra_bpmp_channel *channel)
84{
85	struct tegra210_bpmp *priv = channel->bpmp->priv;
86
87	__raw_writel(MA_ACKD(channel->index), priv->arb_sema + SET_OFFSET);
88
89	return 0;
90}
91
92static int tegra210_bpmp_ack_response(struct tegra_bpmp_channel *channel)
93{
94	struct tegra210_bpmp *priv = channel->bpmp->priv;
95
96	__raw_writel(MA_ACKD(channel->index) ^ MA_FREE(channel->index),
97		     priv->arb_sema + CLR_OFFSET);
98
99	return 0;
100}
101
102static int tegra210_bpmp_ack_request(struct tegra_bpmp_channel *channel)
103{
104	struct tegra210_bpmp *priv = channel->bpmp->priv;
105
106	__raw_writel(SL_QUED(channel->index), priv->arb_sema + SET_OFFSET);
107
108	return 0;
109}
110
111static int tegra210_bpmp_ring_doorbell(struct tegra_bpmp *bpmp)
112{
113	struct tegra210_bpmp *priv = bpmp->priv;
114	struct irq_data *irq_data = priv->tx_irq_data;
115
116	/*
117	 * Tegra Legacy Interrupt Controller (LIC) is used to notify BPMP of
118	 * available messages
119	 */
120	if (irq_data->chip->irq_retrigger)
121		return irq_data->chip->irq_retrigger(irq_data);
122
123	return -EINVAL;
124}
125
126static irqreturn_t rx_irq(int irq, void *data)
127{
128	struct tegra_bpmp *bpmp = data;
129
130	tegra_bpmp_handle_rx(bpmp);
131
132	return IRQ_HANDLED;
133}
134
135static int tegra210_bpmp_channel_init(struct tegra_bpmp_channel *channel,
136				      struct tegra_bpmp *bpmp,
137				      unsigned int index)
138{
139	struct tegra210_bpmp *priv = bpmp->priv;
140	u32 address;
141	void *p;
142
143	/* Retrieve channel base address from BPMP */
144	writel(index << TRIGGER_ID_SHIFT | TRIGGER_CMD_GET,
145	       priv->atomics + TRIGGER_OFFSET);
146	address = readl(priv->atomics + RESULT_OFFSET(index));
147
148	p = devm_ioremap(bpmp->dev, address, 0x80);
149	if (!p)
150		return -ENOMEM;
151
152	channel->ib = p;
153	channel->ob = p;
154	channel->index = index;
155	init_completion(&channel->completion);
156	channel->bpmp = bpmp;
157
158	return 0;
159}
160
161static int tegra210_bpmp_init(struct tegra_bpmp *bpmp)
162{
163	struct platform_device *pdev = to_platform_device(bpmp->dev);
164	struct tegra210_bpmp *priv;
165	struct resource *res;
166	unsigned int i;
167	int err;
168
169	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
170	if (!priv)
171		return -ENOMEM;
172
173	bpmp->priv = priv;
174
175	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
176	priv->atomics = devm_ioremap_resource(&pdev->dev, res);
177	if (IS_ERR(priv->atomics))
178		return PTR_ERR(priv->atomics);
179
180	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
181	priv->arb_sema = devm_ioremap_resource(&pdev->dev, res);
182	if (IS_ERR(priv->arb_sema))
183		return PTR_ERR(priv->arb_sema);
184
185	err = tegra210_bpmp_channel_init(bpmp->tx_channel, bpmp,
186					 bpmp->soc->channels.cpu_tx.offset);
187	if (err < 0)
188		return err;
189
190	err = tegra210_bpmp_channel_init(bpmp->rx_channel, bpmp,
191					 bpmp->soc->channels.cpu_rx.offset);
192	if (err < 0)
193		return err;
194
195	for (i = 0; i < bpmp->threaded.count; i++) {
196		unsigned int index = bpmp->soc->channels.thread.offset + i;
197
198		err = tegra210_bpmp_channel_init(&bpmp->threaded_channels[i],
199						 bpmp, index);
200		if (err < 0)
201			return err;
202	}
203
204	err = platform_get_irq_byname(pdev, "tx");
205	if (err < 0) {
206		dev_err(&pdev->dev, "failed to get TX IRQ: %d\n", err);
207		return err;
208	}
209
210	priv->tx_irq_data = irq_get_irq_data(err);
211	if (!priv->tx_irq_data) {
212		dev_err(&pdev->dev, "failed to get IRQ data for TX IRQ\n");
213		return -ENOENT;
214	}
215
216	err = platform_get_irq_byname(pdev, "rx");
217	if (err < 0) {
218		dev_err(&pdev->dev, "failed to get rx IRQ: %d\n", err);
219		return err;
220	}
221
222	err = devm_request_irq(&pdev->dev, err, rx_irq,
223			       IRQF_NO_SUSPEND, dev_name(&pdev->dev), bpmp);
224	if (err < 0) {
225		dev_err(&pdev->dev, "failed to request IRQ: %d\n", err);
226		return err;
227	}
228
229	return 0;
230}
231
232const struct tegra_bpmp_ops tegra210_bpmp_ops = {
233	.init = tegra210_bpmp_init,
234	.is_response_ready = tegra210_bpmp_is_response_ready,
235	.is_request_ready = tegra210_bpmp_is_request_ready,
236	.ack_response = tegra210_bpmp_ack_response,
237	.ack_request = tegra210_bpmp_ack_request,
238	.is_response_channel_free = tegra210_bpmp_is_response_channel_free,
239	.is_request_channel_free = tegra210_bpmp_is_request_channel_free,
240	.post_response = tegra210_bpmp_post_response,
241	.post_request = tegra210_bpmp_post_request,
242	.ring_doorbell = tegra210_bpmp_ring_doorbell,
243};
244