1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Texas Instruments' K3 Interrupt Router irqchip driver
  4 *
  5 * Copyright (C) 2018-2019 Texas Instruments Incorporated - https://www.ti.com/
  6 *	Lokesh Vutla <lokeshvutla@ti.com>
  7 */
  8
  9#include <linux/err.h>
 10#include <linux/module.h>
 11#include <linux/moduleparam.h>
 12#include <linux/io.h>
 13#include <linux/irqchip.h>
 14#include <linux/irqdomain.h>
 15#include <linux/of_platform.h>
 16#include <linux/of_address.h>
 17#include <linux/of_irq.h>
 18#include <linux/soc/ti/ti_sci_protocol.h>
 19
 20/**
 21 * struct ti_sci_intr_irq_domain - Structure representing a TISCI based
 22 *				   Interrupt Router IRQ domain.
 23 * @sci:	Pointer to TISCI handle
 24 * @out_irqs:	TISCI resource pointer representing INTR irqs.
 25 * @dev:	Struct device pointer.
 26 * @ti_sci_id:	TI-SCI device identifier
 27 * @type:	Specifies the trigger type supported by this Interrupt Router
 28 */
 29struct ti_sci_intr_irq_domain {
 30	const struct ti_sci_handle *sci;
 31	struct ti_sci_resource *out_irqs;
 32	struct device *dev;
 33	u32 ti_sci_id;
 34	u32 type;
 35};
 36
 37static struct irq_chip ti_sci_intr_irq_chip = {
 38	.name			= "INTR",
 39	.irq_eoi		= irq_chip_eoi_parent,
 40	.irq_mask		= irq_chip_mask_parent,
 41	.irq_unmask		= irq_chip_unmask_parent,
 42	.irq_set_type		= irq_chip_set_type_parent,
 43	.irq_retrigger		= irq_chip_retrigger_hierarchy,
 44	.irq_set_affinity	= irq_chip_set_affinity_parent,
 45};
 46
 47/**
 48 * ti_sci_intr_irq_domain_translate() - Retrieve hwirq and type from
 49 *					IRQ firmware specific handler.
 50 * @domain:	Pointer to IRQ domain
 51 * @fwspec:	Pointer to IRQ specific firmware structure
 52 * @hwirq:	IRQ number identified by hardware
 53 * @type:	IRQ type
 54 *
 55 * Return 0 if all went ok else appropriate error.
 56 */
 57static int ti_sci_intr_irq_domain_translate(struct irq_domain *domain,
 58					    struct irq_fwspec *fwspec,
 59					    unsigned long *hwirq,
 60					    unsigned int *type)
 61{
 62	struct ti_sci_intr_irq_domain *intr = domain->host_data;
 63
 64	if (fwspec->param_count != 1)
 65		return -EINVAL;
 66
 67	*hwirq = fwspec->param[0];
 68	*type = intr->type;
 69
 70	return 0;
 71}
 72
 73/**
 74 * ti_sci_intr_xlate_irq() - Translate hwirq to parent's hwirq.
 75 * @intr:	IRQ domain corresponding to Interrupt Router
 76 * @irq:	Hardware irq corresponding to the above irq domain
 77 *
 78 * Return parent irq number if translation is available else -ENOENT.
 79 */
 80static int ti_sci_intr_xlate_irq(struct ti_sci_intr_irq_domain *intr, u32 irq)
 81{
 82	struct device_node *np = dev_of_node(intr->dev);
 83	u32 base, pbase, size, len;
 84	const __be32 *range;
 85
 86	range = of_get_property(np, "ti,interrupt-ranges", &len);
 87	if (!range)
 88		return irq;
 89
 90	for (len /= sizeof(*range); len >= 3; len -= 3) {
 91		base = be32_to_cpu(*range++);
 92		pbase = be32_to_cpu(*range++);
 93		size = be32_to_cpu(*range++);
 94
 95		if (base <= irq && irq < base + size)
 96			return irq - base + pbase;
 97	}
 98
 99	return -ENOENT;
100}
101
102/**
103 * ti_sci_intr_irq_domain_free() - Free the specified IRQs from the domain.
104 * @domain:	Domain to which the irqs belong
105 * @virq:	Linux virtual IRQ to be freed.
106 * @nr_irqs:	Number of continuous irqs to be freed
107 */
108static void ti_sci_intr_irq_domain_free(struct irq_domain *domain,
109					unsigned int virq, unsigned int nr_irqs)
110{
111	struct ti_sci_intr_irq_domain *intr = domain->host_data;
112	struct irq_data *data;
113	int out_irq;
114
115	data = irq_domain_get_irq_data(domain, virq);
116	out_irq = (uintptr_t)data->chip_data;
117
118	intr->sci->ops.rm_irq_ops.free_irq(intr->sci,
119					   intr->ti_sci_id, data->hwirq,
120					   intr->ti_sci_id, out_irq);
121	ti_sci_release_resource(intr->out_irqs, out_irq);
122	irq_domain_free_irqs_parent(domain, virq, 1);
123	irq_domain_reset_irq_data(data);
124}
125
126/**
127 * ti_sci_intr_alloc_parent_irq() - Allocate parent IRQ
128 * @domain:	Pointer to the interrupt router IRQ domain
129 * @virq:	Corresponding Linux virtual IRQ number
130 * @hwirq:	Corresponding hwirq for the IRQ within this IRQ domain
131 *
132 * Returns intr output irq if all went well else appropriate error pointer.
133 */
134static int ti_sci_intr_alloc_parent_irq(struct irq_domain *domain,
135					unsigned int virq, u32 hwirq)
136{
137	struct ti_sci_intr_irq_domain *intr = domain->host_data;
138	struct device_node *parent_node;
139	struct irq_fwspec fwspec;
140	int p_hwirq, err = 0;
141	u16 out_irq;
142
143	out_irq = ti_sci_get_free_resource(intr->out_irqs);
144	if (out_irq == TI_SCI_RESOURCE_NULL)
145		return -EINVAL;
146
147	p_hwirq = ti_sci_intr_xlate_irq(intr, out_irq);
148	if (p_hwirq < 0)
149		goto err_irqs;
150
151	parent_node = of_irq_find_parent(dev_of_node(intr->dev));
152	fwspec.fwnode = of_node_to_fwnode(parent_node);
153
154	if (of_device_is_compatible(parent_node, "arm,gic-v3")) {
155		/* Parent is GIC */
156		fwspec.param_count = 3;
157		fwspec.param[0] = 0;	/* SPI */
158		fwspec.param[1] = p_hwirq - 32; /* SPI offset */
159		fwspec.param[2] = intr->type;
160	} else {
161		/* Parent is Interrupt Router */
162		fwspec.param_count = 1;
163		fwspec.param[0] = p_hwirq;
164	}
165
166	err = irq_domain_alloc_irqs_parent(domain, virq, 1, &fwspec);
167	if (err)
168		goto err_irqs;
169
170	err = intr->sci->ops.rm_irq_ops.set_irq(intr->sci,
171						intr->ti_sci_id, hwirq,
172						intr->ti_sci_id, out_irq);
173	if (err)
174		goto err_msg;
175
176	return out_irq;
177
178err_msg:
179	irq_domain_free_irqs_parent(domain, virq, 1);
180err_irqs:
181	ti_sci_release_resource(intr->out_irqs, out_irq);
182	return err;
183}
184
185/**
186 * ti_sci_intr_irq_domain_alloc() - Allocate Interrupt router IRQs
187 * @domain:	Point to the interrupt router IRQ domain
188 * @virq:	Corresponding Linux virtual IRQ number
189 * @nr_irqs:	Continuous irqs to be allocated
190 * @data:	Pointer to firmware specifier
191 *
192 * Return 0 if all went well else appropriate error value.
193 */
194static int ti_sci_intr_irq_domain_alloc(struct irq_domain *domain,
195					unsigned int virq, unsigned int nr_irqs,
196					void *data)
197{
198	struct irq_fwspec *fwspec = data;
199	unsigned long hwirq;
200	unsigned int flags;
201	int err, out_irq;
202
203	err = ti_sci_intr_irq_domain_translate(domain, fwspec, &hwirq, &flags);
204	if (err)
205		return err;
206
207	out_irq = ti_sci_intr_alloc_parent_irq(domain, virq, hwirq);
208	if (out_irq < 0)
209		return out_irq;
210
211	irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
212				      &ti_sci_intr_irq_chip,
213				      (void *)(uintptr_t)out_irq);
214
215	return 0;
216}
217
218static const struct irq_domain_ops ti_sci_intr_irq_domain_ops = {
219	.free		= ti_sci_intr_irq_domain_free,
220	.alloc		= ti_sci_intr_irq_domain_alloc,
221	.translate	= ti_sci_intr_irq_domain_translate,
222};
223
224static int ti_sci_intr_irq_domain_probe(struct platform_device *pdev)
225{
226	struct irq_domain *parent_domain, *domain;
227	struct ti_sci_intr_irq_domain *intr;
228	struct device_node *parent_node;
229	struct device *dev = &pdev->dev;
230	int ret;
231
232	parent_node = of_irq_find_parent(dev_of_node(dev));
233	if (!parent_node) {
234		dev_err(dev, "Failed to get IRQ parent node\n");
235		return -ENODEV;
236	}
237
238	parent_domain = irq_find_host(parent_node);
239	if (!parent_domain) {
240		dev_err(dev, "Failed to find IRQ parent domain\n");
241		return -ENODEV;
242	}
243
244	intr = devm_kzalloc(dev, sizeof(*intr), GFP_KERNEL);
245	if (!intr)
246		return -ENOMEM;
247
248	intr->dev = dev;
249	ret = of_property_read_u32(dev_of_node(dev), "ti,intr-trigger-type",
250				   &intr->type);
251	if (ret) {
252		dev_err(dev, "missing ti,intr-trigger-type property\n");
253		return -EINVAL;
254	}
255
256	intr->sci = devm_ti_sci_get_by_phandle(dev, "ti,sci");
257	if (IS_ERR(intr->sci))
258		return dev_err_probe(dev, PTR_ERR(intr->sci),
259				     "ti,sci read fail\n");
260
261	ret = of_property_read_u32(dev_of_node(dev), "ti,sci-dev-id",
262				   &intr->ti_sci_id);
263	if (ret) {
264		dev_err(dev, "missing 'ti,sci-dev-id' property\n");
265		return -EINVAL;
266	}
267
268	intr->out_irqs = devm_ti_sci_get_resource(intr->sci, dev,
269						  intr->ti_sci_id,
270						  TI_SCI_RESASG_SUBTYPE_IR_OUTPUT);
271	if (IS_ERR(intr->out_irqs)) {
272		dev_err(dev, "Destination irq resource allocation failed\n");
273		return PTR_ERR(intr->out_irqs);
274	}
275
276	domain = irq_domain_add_hierarchy(parent_domain, 0, 0, dev_of_node(dev),
277					  &ti_sci_intr_irq_domain_ops, intr);
278	if (!domain) {
279		dev_err(dev, "Failed to allocate IRQ domain\n");
280		return -ENOMEM;
281	}
282
283	dev_info(dev, "Interrupt Router %d domain created\n", intr->ti_sci_id);
284
285	return 0;
286}
287
288static const struct of_device_id ti_sci_intr_irq_domain_of_match[] = {
289	{ .compatible = "ti,sci-intr", },
290	{ /* sentinel */ },
291};
292MODULE_DEVICE_TABLE(of, ti_sci_intr_irq_domain_of_match);
293
294static struct platform_driver ti_sci_intr_irq_domain_driver = {
295	.probe = ti_sci_intr_irq_domain_probe,
296	.driver = {
297		.name = "ti-sci-intr",
298		.of_match_table = ti_sci_intr_irq_domain_of_match,
299	},
300};
301module_platform_driver(ti_sci_intr_irq_domain_driver);
302
303MODULE_AUTHOR("Lokesh Vutla <lokeshvutla@ticom>");
304MODULE_DESCRIPTION("K3 Interrupt Router driver over TI SCI protocol");
305MODULE_LICENSE("GPL v2");