xref: /openbmc/linux/drivers/irqchip/irq-mvebu-icu.c (revision 00885a77c8ffbeee58a9662c92d6a60a9b49f120)
1 /*
2  * Copyright (C) 2017 Marvell
3  *
4  * Hanna Hawa <hannah@marvell.com>
5  * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
6  *
7  * This file is licensed under the terms of the GNU General Public
8  * License version 2. This program is licensed "as is" without any
9  * warranty of any kind, whether express or implied.
10  */
11 
12 #include <linux/interrupt.h>
13 #include <linux/irq.h>
14 #include <linux/irqchip.h>
15 #include <linux/irqdomain.h>
16 #include <linux/kernel.h>
17 #include <linux/msi.h>
18 #include <linux/of_irq.h>
19 #include <linux/of_platform.h>
20 #include <linux/platform_device.h>
21 
22 #include <dt-bindings/interrupt-controller/mvebu-icu.h>
23 
24 /* ICU registers */
25 #define ICU_SETSPI_NSR_AL	0x10
26 #define ICU_SETSPI_NSR_AH	0x14
27 #define ICU_CLRSPI_NSR_AL	0x18
28 #define ICU_CLRSPI_NSR_AH	0x1c
29 #define ICU_INT_CFG(x)          (0x100 + 4 * (x))
30 #define   ICU_INT_ENABLE	BIT(24)
31 #define   ICU_IS_EDGE		BIT(28)
32 #define   ICU_GROUP_SHIFT	29
33 
34 /* ICU definitions */
35 #define ICU_MAX_IRQS		207
36 #define ICU_SATA0_ICU_ID	109
37 #define ICU_SATA1_ICU_ID	107
38 
39 struct mvebu_icu {
40 	struct irq_chip irq_chip;
41 	void __iomem *base;
42 	struct device *dev;
43 	atomic_t initialized;
44 };
45 
46 struct mvebu_icu_irq_data {
47 	struct mvebu_icu *icu;
48 	unsigned int icu_group;
49 	unsigned int type;
50 };
51 
52 static void mvebu_icu_init(struct mvebu_icu *icu, struct msi_msg *msg)
53 {
54 	if (atomic_cmpxchg(&icu->initialized, false, true))
55 		return;
56 
57 	/* Set Clear/Set ICU SPI message address in AP */
58 	writel_relaxed(msg[0].address_hi, icu->base + ICU_SETSPI_NSR_AH);
59 	writel_relaxed(msg[0].address_lo, icu->base + ICU_SETSPI_NSR_AL);
60 	writel_relaxed(msg[1].address_hi, icu->base + ICU_CLRSPI_NSR_AH);
61 	writel_relaxed(msg[1].address_lo, icu->base + ICU_CLRSPI_NSR_AL);
62 }
63 
64 static void mvebu_icu_write_msg(struct msi_desc *desc, struct msi_msg *msg)
65 {
66 	struct irq_data *d = irq_get_irq_data(desc->irq);
67 	struct mvebu_icu_irq_data *icu_irqd = d->chip_data;
68 	struct mvebu_icu *icu = icu_irqd->icu;
69 	unsigned int icu_int;
70 
71 	if (msg->address_lo || msg->address_hi) {
72 		/* One off initialization */
73 		mvebu_icu_init(icu, msg);
74 		/* Configure the ICU with irq number & type */
75 		icu_int = msg->data | ICU_INT_ENABLE;
76 		if (icu_irqd->type & IRQ_TYPE_EDGE_RISING)
77 			icu_int |= ICU_IS_EDGE;
78 		icu_int |= icu_irqd->icu_group << ICU_GROUP_SHIFT;
79 	} else {
80 		/* De-configure the ICU */
81 		icu_int = 0;
82 	}
83 
84 	writel_relaxed(icu_int, icu->base + ICU_INT_CFG(d->hwirq));
85 
86 	/*
87 	 * The SATA unit has 2 ports, and a dedicated ICU entry per
88 	 * port. The ahci sata driver supports only one irq interrupt
89 	 * per SATA unit. To solve this conflict, we configure the 2
90 	 * SATA wired interrupts in the south bridge into 1 GIC
91 	 * interrupt in the north bridge. Even if only a single port
92 	 * is enabled, if sata node is enabled, both interrupts are
93 	 * configured (regardless of which port is actually in use).
94 	 */
95 	if (d->hwirq == ICU_SATA0_ICU_ID || d->hwirq == ICU_SATA1_ICU_ID) {
96 		writel_relaxed(icu_int,
97 			       icu->base + ICU_INT_CFG(ICU_SATA0_ICU_ID));
98 		writel_relaxed(icu_int,
99 			       icu->base + ICU_INT_CFG(ICU_SATA1_ICU_ID));
100 	}
101 }
102 
103 static int
104 mvebu_icu_irq_domain_translate(struct irq_domain *d, struct irq_fwspec *fwspec,
105 			       unsigned long *hwirq, unsigned int *type)
106 {
107 	struct mvebu_icu *icu = platform_msi_get_host_data(d);
108 	unsigned int icu_group;
109 
110 	/* Check the count of the parameters in dt */
111 	if (WARN_ON(fwspec->param_count < 3)) {
112 		dev_err(icu->dev, "wrong ICU parameter count %d\n",
113 			fwspec->param_count);
114 		return -EINVAL;
115 	}
116 
117 	/* Only ICU group type is handled */
118 	icu_group = fwspec->param[0];
119 	if (icu_group != ICU_GRP_NSR && icu_group != ICU_GRP_SR &&
120 	    icu_group != ICU_GRP_SEI && icu_group != ICU_GRP_REI) {
121 		dev_err(icu->dev, "wrong ICU group type %x\n", icu_group);
122 		return -EINVAL;
123 	}
124 
125 	*hwirq = fwspec->param[1];
126 	if (*hwirq >= ICU_MAX_IRQS) {
127 		dev_err(icu->dev, "invalid interrupt number %ld\n", *hwirq);
128 		return -EINVAL;
129 	}
130 
131 	/* Mask the type to prevent wrong DT configuration */
132 	*type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK;
133 
134 	return 0;
135 }
136 
137 static int
138 mvebu_icu_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
139 			   unsigned int nr_irqs, void *args)
140 {
141 	int err;
142 	unsigned long hwirq;
143 	struct irq_fwspec *fwspec = args;
144 	struct mvebu_icu *icu = platform_msi_get_host_data(domain);
145 	struct mvebu_icu_irq_data *icu_irqd;
146 
147 	icu_irqd = kmalloc(sizeof(*icu_irqd), GFP_KERNEL);
148 	if (!icu_irqd)
149 		return -ENOMEM;
150 
151 	err = mvebu_icu_irq_domain_translate(domain, fwspec, &hwirq,
152 					     &icu_irqd->type);
153 	if (err) {
154 		dev_err(icu->dev, "failed to translate ICU parameters\n");
155 		goto free_irqd;
156 	}
157 
158 	icu_irqd->icu_group = fwspec->param[0];
159 	icu_irqd->icu = icu;
160 
161 	err = platform_msi_domain_alloc(domain, virq, nr_irqs);
162 	if (err) {
163 		dev_err(icu->dev, "failed to allocate ICU interrupt in parent domain\n");
164 		goto free_irqd;
165 	}
166 
167 	/* Make sure there is no interrupt left pending by the firmware */
168 	err = irq_set_irqchip_state(virq, IRQCHIP_STATE_PENDING, false);
169 	if (err)
170 		goto free_msi;
171 
172 	err = irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
173 					    &icu->irq_chip, icu_irqd);
174 	if (err) {
175 		dev_err(icu->dev, "failed to set the data to IRQ domain\n");
176 		goto free_msi;
177 	}
178 
179 	return 0;
180 
181 free_msi:
182 	platform_msi_domain_free(domain, virq, nr_irqs);
183 free_irqd:
184 	kfree(icu_irqd);
185 	return err;
186 }
187 
188 static void
189 mvebu_icu_irq_domain_free(struct irq_domain *domain, unsigned int virq,
190 			  unsigned int nr_irqs)
191 {
192 	struct irq_data *d = irq_get_irq_data(virq);
193 	struct mvebu_icu_irq_data *icu_irqd = d->chip_data;
194 
195 	kfree(icu_irqd);
196 
197 	platform_msi_domain_free(domain, virq, nr_irqs);
198 }
199 
200 static const struct irq_domain_ops mvebu_icu_domain_ops = {
201 	.translate = mvebu_icu_irq_domain_translate,
202 	.alloc     = mvebu_icu_irq_domain_alloc,
203 	.free      = mvebu_icu_irq_domain_free,
204 };
205 
206 static int mvebu_icu_subset_probe(struct platform_device *pdev)
207 {
208 	struct device_node *msi_parent_dn;
209 	struct device *dev = &pdev->dev;
210 	struct irq_domain *irq_domain;
211 	struct mvebu_icu *icu;
212 
213 	icu = dev_get_drvdata(dev);
214 
215 	dev->msi_domain = of_msi_get_domain(dev, dev->of_node,
216 					    DOMAIN_BUS_PLATFORM_MSI);
217 	if (!dev->msi_domain)
218 		return -EPROBE_DEFER;
219 
220 	msi_parent_dn = irq_domain_get_of_node(dev->msi_domain);
221 	if (!msi_parent_dn)
222 		return -ENODEV;
223 
224 	irq_domain = platform_msi_create_device_tree_domain(dev, ICU_MAX_IRQS,
225 							    mvebu_icu_write_msg,
226 							    &mvebu_icu_domain_ops,
227 							    icu);
228 	if (!irq_domain) {
229 		dev_err(dev, "Failed to create ICU MSI domain\n");
230 		return -ENOMEM;
231 	}
232 
233 	return 0;
234 }
235 
236 static int mvebu_icu_probe(struct platform_device *pdev)
237 {
238 	struct mvebu_icu *icu;
239 	struct resource *res;
240 	int i;
241 
242 	icu = devm_kzalloc(&pdev->dev, sizeof(struct mvebu_icu),
243 			   GFP_KERNEL);
244 	if (!icu)
245 		return -ENOMEM;
246 
247 	icu->dev = &pdev->dev;
248 
249 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
250 	icu->base = devm_ioremap_resource(&pdev->dev, res);
251 	if (IS_ERR(icu->base)) {
252 		dev_err(&pdev->dev, "Failed to map icu base address.\n");
253 		return PTR_ERR(icu->base);
254 	}
255 
256 	icu->irq_chip.name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
257 					    "ICU.%x",
258 					    (unsigned int)res->start);
259 	if (!icu->irq_chip.name)
260 		return -ENOMEM;
261 
262 	icu->irq_chip.irq_mask = irq_chip_mask_parent;
263 	icu->irq_chip.irq_unmask = irq_chip_unmask_parent;
264 	icu->irq_chip.irq_eoi = irq_chip_eoi_parent;
265 	icu->irq_chip.irq_set_type = irq_chip_set_type_parent;
266 #ifdef CONFIG_SMP
267 	icu->irq_chip.irq_set_affinity = irq_chip_set_affinity_parent;
268 #endif
269 
270 	/*
271 	 * Clean all ICU interrupts with type SPI_NSR, required to
272 	 * avoid unpredictable SPI assignments done by firmware.
273 	 */
274 	for (i = 0 ; i < ICU_MAX_IRQS ; i++) {
275 		u32 icu_int, icu_grp;
276 
277 		icu_int = readl_relaxed(icu->base + ICU_INT_CFG(i));
278 		icu_grp = icu_int >> ICU_GROUP_SHIFT;
279 
280 		if (icu_grp == ICU_GRP_NSR)
281 			writel_relaxed(0x0, icu->base + ICU_INT_CFG(i));
282 	}
283 
284 	platform_set_drvdata(pdev, icu);
285 
286 	return mvebu_icu_subset_probe(pdev);
287 }
288 
289 static const struct of_device_id mvebu_icu_of_match[] = {
290 	{ .compatible = "marvell,cp110-icu", },
291 	{},
292 };
293 
294 static struct platform_driver mvebu_icu_driver = {
295 	.probe  = mvebu_icu_probe,
296 	.driver = {
297 		.name = "mvebu-icu",
298 		.of_match_table = mvebu_icu_of_match,
299 	},
300 };
301 builtin_platform_driver(mvebu_icu_driver);
302