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	void __iomem *p;
141	u32 address;
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	iosys_map_set_vaddr_iomem(&channel->ib, p);
153	iosys_map_set_vaddr_iomem(&channel->ob, p);
154
155	channel->index = index;
156	init_completion(&channel->completion);
157	channel->bpmp = bpmp;
158
159	return 0;
160}
161
162static int tegra210_bpmp_init(struct tegra_bpmp *bpmp)
163{
164	struct platform_device *pdev = to_platform_device(bpmp->dev);
165	struct tegra210_bpmp *priv;
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	priv->atomics = devm_platform_ioremap_resource(pdev, 0);
176	if (IS_ERR(priv->atomics))
177		return PTR_ERR(priv->atomics);
178
179	priv->arb_sema = devm_platform_ioremap_resource(pdev, 1);
180	if (IS_ERR(priv->arb_sema))
181		return PTR_ERR(priv->arb_sema);
182
183	err = tegra210_bpmp_channel_init(bpmp->tx_channel, bpmp,
184					 bpmp->soc->channels.cpu_tx.offset);
185	if (err < 0)
186		return err;
187
188	err = tegra210_bpmp_channel_init(bpmp->rx_channel, bpmp,
189					 bpmp->soc->channels.cpu_rx.offset);
190	if (err < 0)
191		return err;
192
193	for (i = 0; i < bpmp->threaded.count; i++) {
194		unsigned int index = bpmp->soc->channels.thread.offset + i;
195
196		err = tegra210_bpmp_channel_init(&bpmp->threaded_channels[i],
197						 bpmp, index);
198		if (err < 0)
199			return err;
200	}
201
202	err = platform_get_irq_byname(pdev, "tx");
203	if (err < 0)
204		return err;
205
206	priv->tx_irq_data = irq_get_irq_data(err);
207	if (!priv->tx_irq_data) {
208		dev_err(&pdev->dev, "failed to get IRQ data for TX IRQ\n");
209		return -ENOENT;
210	}
211
212	err = platform_get_irq_byname(pdev, "rx");
213	if (err < 0)
214		return err;
215
216	err = devm_request_irq(&pdev->dev, err, rx_irq,
217			       IRQF_NO_SUSPEND, dev_name(&pdev->dev), bpmp);
218	if (err < 0) {
219		dev_err(&pdev->dev, "failed to request IRQ: %d\n", err);
220		return err;
221	}
222
223	return 0;
224}
225
226const struct tegra_bpmp_ops tegra210_bpmp_ops = {
227	.init = tegra210_bpmp_init,
228	.is_response_ready = tegra210_bpmp_is_response_ready,
229	.is_request_ready = tegra210_bpmp_is_request_ready,
230	.ack_response = tegra210_bpmp_ack_response,
231	.ack_request = tegra210_bpmp_ack_request,
232	.is_response_channel_free = tegra210_bpmp_is_response_channel_free,
233	.is_request_channel_free = tegra210_bpmp_is_request_channel_free,
234	.post_response = tegra210_bpmp_post_response,
235	.post_request = tegra210_bpmp_post_request,
236	.ring_doorbell = tegra210_bpmp_ring_doorbell,
237};
238