1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.
4 */
5
6 #include <linux/bitfield.h>
7 #include <linux/interrupt.h>
8 #include <linux/irq.h>
9 #include <linux/irqdomain.h>
10 #include <linux/mailbox_controller.h>
11 #include <linux/module.h>
12 #include <linux/platform_device.h>
13
14 #include <dt-bindings/mailbox/qcom-ipcc.h>
15
16 #define IPCC_MBOX_MAX_CHAN 48
17
18 /* IPCC Register offsets */
19 #define IPCC_REG_SEND_ID 0x0c
20 #define IPCC_REG_RECV_ID 0x10
21 #define IPCC_REG_RECV_SIGNAL_ENABLE 0x14
22 #define IPCC_REG_RECV_SIGNAL_DISABLE 0x18
23 #define IPCC_REG_RECV_SIGNAL_CLEAR 0x1c
24 #define IPCC_REG_CLIENT_CLEAR 0x38
25
26 #define IPCC_SIGNAL_ID_MASK GENMASK(15, 0)
27 #define IPCC_CLIENT_ID_MASK GENMASK(31, 16)
28
29 #define IPCC_NO_PENDING_IRQ GENMASK(31, 0)
30
31 /**
32 * struct qcom_ipcc_chan_info - Per-mailbox-channel info
33 * @client_id: The client-id to which the interrupt has to be triggered
34 * @signal_id: The signal-id to which the interrupt has to be triggered
35 */
36 struct qcom_ipcc_chan_info {
37 u16 client_id;
38 u16 signal_id;
39 };
40
41 /**
42 * struct qcom_ipcc - Holder for the mailbox driver
43 * @dev: Device associated with this instance
44 * @base: Base address of the IPCC frame associated to APSS
45 * @irq_domain: The irq_domain associated with this instance
46 * @chan: The mailbox channels array
47 * @mchan: The per-mailbox channel info array
48 * @mbox: The mailbox controller
49 * @irq: Summary irq
50 */
51 struct qcom_ipcc {
52 struct device *dev;
53 void __iomem *base;
54 struct irq_domain *irq_domain;
55 struct mbox_chan chan[IPCC_MBOX_MAX_CHAN];
56 struct qcom_ipcc_chan_info mchan[IPCC_MBOX_MAX_CHAN];
57 struct mbox_controller mbox;
58 int irq;
59 };
60
to_qcom_ipcc(struct mbox_controller * mbox)61 static inline struct qcom_ipcc *to_qcom_ipcc(struct mbox_controller *mbox)
62 {
63 return container_of(mbox, struct qcom_ipcc, mbox);
64 }
65
qcom_ipcc_get_hwirq(u16 client_id,u16 signal_id)66 static inline u32 qcom_ipcc_get_hwirq(u16 client_id, u16 signal_id)
67 {
68 return FIELD_PREP(IPCC_CLIENT_ID_MASK, client_id) |
69 FIELD_PREP(IPCC_SIGNAL_ID_MASK, signal_id);
70 }
71
qcom_ipcc_irq_fn(int irq,void * data)72 static irqreturn_t qcom_ipcc_irq_fn(int irq, void *data)
73 {
74 struct qcom_ipcc *ipcc = data;
75 u32 hwirq;
76 int virq;
77
78 for (;;) {
79 hwirq = readl(ipcc->base + IPCC_REG_RECV_ID);
80 if (hwirq == IPCC_NO_PENDING_IRQ)
81 break;
82
83 virq = irq_find_mapping(ipcc->irq_domain, hwirq);
84 writel(hwirq, ipcc->base + IPCC_REG_RECV_SIGNAL_CLEAR);
85 generic_handle_irq(virq);
86 }
87
88 return IRQ_HANDLED;
89 }
90
qcom_ipcc_mask_irq(struct irq_data * irqd)91 static void qcom_ipcc_mask_irq(struct irq_data *irqd)
92 {
93 struct qcom_ipcc *ipcc = irq_data_get_irq_chip_data(irqd);
94 irq_hw_number_t hwirq = irqd_to_hwirq(irqd);
95
96 writel(hwirq, ipcc->base + IPCC_REG_RECV_SIGNAL_DISABLE);
97 }
98
qcom_ipcc_unmask_irq(struct irq_data * irqd)99 static void qcom_ipcc_unmask_irq(struct irq_data *irqd)
100 {
101 struct qcom_ipcc *ipcc = irq_data_get_irq_chip_data(irqd);
102 irq_hw_number_t hwirq = irqd_to_hwirq(irqd);
103
104 writel(hwirq, ipcc->base + IPCC_REG_RECV_SIGNAL_ENABLE);
105 }
106
107 static struct irq_chip qcom_ipcc_irq_chip = {
108 .name = "ipcc",
109 .irq_mask = qcom_ipcc_mask_irq,
110 .irq_unmask = qcom_ipcc_unmask_irq,
111 .flags = IRQCHIP_SKIP_SET_WAKE,
112 };
113
qcom_ipcc_domain_map(struct irq_domain * d,unsigned int irq,irq_hw_number_t hw)114 static int qcom_ipcc_domain_map(struct irq_domain *d, unsigned int irq,
115 irq_hw_number_t hw)
116 {
117 struct qcom_ipcc *ipcc = d->host_data;
118
119 irq_set_chip_and_handler(irq, &qcom_ipcc_irq_chip, handle_level_irq);
120 irq_set_chip_data(irq, ipcc);
121 irq_set_noprobe(irq);
122
123 return 0;
124 }
125
qcom_ipcc_domain_xlate(struct irq_domain * d,struct device_node * node,const u32 * intspec,unsigned int intsize,unsigned long * out_hwirq,unsigned int * out_type)126 static int qcom_ipcc_domain_xlate(struct irq_domain *d,
127 struct device_node *node, const u32 *intspec,
128 unsigned int intsize,
129 unsigned long *out_hwirq,
130 unsigned int *out_type)
131 {
132 if (intsize != 3)
133 return -EINVAL;
134
135 *out_hwirq = qcom_ipcc_get_hwirq(intspec[0], intspec[1]);
136 *out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;
137
138 return 0;
139 }
140
141 static const struct irq_domain_ops qcom_ipcc_irq_ops = {
142 .map = qcom_ipcc_domain_map,
143 .xlate = qcom_ipcc_domain_xlate,
144 };
145
qcom_ipcc_mbox_send_data(struct mbox_chan * chan,void * data)146 static int qcom_ipcc_mbox_send_data(struct mbox_chan *chan, void *data)
147 {
148 struct qcom_ipcc *ipcc = to_qcom_ipcc(chan->mbox);
149 struct qcom_ipcc_chan_info *mchan = chan->con_priv;
150 u32 hwirq;
151
152 hwirq = qcom_ipcc_get_hwirq(mchan->client_id, mchan->signal_id);
153 writel(hwirq, ipcc->base + IPCC_REG_SEND_ID);
154
155 return 0;
156 }
157
qcom_ipcc_mbox_shutdown(struct mbox_chan * chan)158 static void qcom_ipcc_mbox_shutdown(struct mbox_chan *chan)
159 {
160 chan->con_priv = NULL;
161 }
162
qcom_ipcc_mbox_xlate(struct mbox_controller * mbox,const struct of_phandle_args * ph)163 static struct mbox_chan *qcom_ipcc_mbox_xlate(struct mbox_controller *mbox,
164 const struct of_phandle_args *ph)
165 {
166 struct qcom_ipcc *ipcc = to_qcom_ipcc(mbox);
167 struct qcom_ipcc_chan_info *mchan;
168 struct mbox_chan *chan;
169 unsigned int i;
170
171 if (ph->args_count != 2)
172 return ERR_PTR(-EINVAL);
173
174 for (i = 0; i < IPCC_MBOX_MAX_CHAN; i++) {
175 chan = &ipcc->chan[i];
176 if (!chan->con_priv) {
177 mchan = &ipcc->mchan[i];
178 mchan->client_id = ph->args[0];
179 mchan->signal_id = ph->args[1];
180 chan->con_priv = mchan;
181 break;
182 }
183
184 chan = NULL;
185 }
186
187 return chan ?: ERR_PTR(-EBUSY);
188 }
189
190 static const struct mbox_chan_ops ipcc_mbox_chan_ops = {
191 .send_data = qcom_ipcc_mbox_send_data,
192 .shutdown = qcom_ipcc_mbox_shutdown,
193 };
194
qcom_ipcc_setup_mbox(struct qcom_ipcc * ipcc)195 static int qcom_ipcc_setup_mbox(struct qcom_ipcc *ipcc)
196 {
197 struct mbox_controller *mbox;
198 struct device *dev = ipcc->dev;
199
200 mbox = &ipcc->mbox;
201 mbox->dev = dev;
202 mbox->num_chans = IPCC_MBOX_MAX_CHAN;
203 mbox->chans = ipcc->chan;
204 mbox->ops = &ipcc_mbox_chan_ops;
205 mbox->of_xlate = qcom_ipcc_mbox_xlate;
206 mbox->txdone_irq = false;
207 mbox->txdone_poll = false;
208
209 return devm_mbox_controller_register(dev, mbox);
210 }
211
qcom_ipcc_probe(struct platform_device * pdev)212 static int qcom_ipcc_probe(struct platform_device *pdev)
213 {
214 struct qcom_ipcc *ipcc;
215 int ret;
216
217 ipcc = devm_kzalloc(&pdev->dev, sizeof(*ipcc), GFP_KERNEL);
218 if (!ipcc)
219 return -ENOMEM;
220
221 ipcc->dev = &pdev->dev;
222
223 ipcc->base = devm_platform_ioremap_resource(pdev, 0);
224 if (IS_ERR(ipcc->base))
225 return PTR_ERR(ipcc->base);
226
227 ipcc->irq = platform_get_irq(pdev, 0);
228 if (ipcc->irq < 0)
229 return ipcc->irq;
230
231 ipcc->irq_domain = irq_domain_add_tree(pdev->dev.of_node,
232 &qcom_ipcc_irq_ops, ipcc);
233 if (!ipcc->irq_domain)
234 return -ENOMEM;
235
236 ret = qcom_ipcc_setup_mbox(ipcc);
237 if (ret)
238 goto err_mbox;
239
240 ret = devm_request_irq(&pdev->dev, ipcc->irq, qcom_ipcc_irq_fn,
241 IRQF_TRIGGER_HIGH, "ipcc", ipcc);
242 if (ret < 0) {
243 dev_err(&pdev->dev, "Failed to register the irq: %d\n", ret);
244 goto err_mbox;
245 }
246
247 enable_irq_wake(ipcc->irq);
248 platform_set_drvdata(pdev, ipcc);
249
250 return 0;
251
252 err_mbox:
253 irq_domain_remove(ipcc->irq_domain);
254
255 return ret;
256 }
257
qcom_ipcc_remove(struct platform_device * pdev)258 static int qcom_ipcc_remove(struct platform_device *pdev)
259 {
260 struct qcom_ipcc *ipcc = platform_get_drvdata(pdev);
261
262 disable_irq_wake(ipcc->irq);
263 irq_domain_remove(ipcc->irq_domain);
264
265 return 0;
266 }
267
268 static const struct of_device_id qcom_ipcc_of_match[] = {
269 { .compatible = "qcom,ipcc"},
270 {}
271 };
272 MODULE_DEVICE_TABLE(of, qcom_ipcc_of_match);
273
274 static struct platform_driver qcom_ipcc_driver = {
275 .probe = qcom_ipcc_probe,
276 .remove = qcom_ipcc_remove,
277 .driver = {
278 .name = "qcom-ipcc",
279 .of_match_table = qcom_ipcc_of_match,
280 .suppress_bind_attrs = true,
281 },
282 };
283
qcom_ipcc_init(void)284 static int __init qcom_ipcc_init(void)
285 {
286 return platform_driver_register(&qcom_ipcc_driver);
287 }
288 arch_initcall(qcom_ipcc_init);
289
290 MODULE_AUTHOR("Venkata Narendra Kumar Gutta <vnkgutta@codeaurora.org>");
291 MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>");
292 MODULE_DESCRIPTION("Qualcomm Technologies, Inc. IPCC driver");
293 MODULE_LICENSE("GPL v2");
294