xref: /linux/drivers/irqchip/irq-riscv-aplic-main.c (revision a3a02a52bcfcbcc4a637d4b68bf1bc391c9fad02)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2021 Western Digital Corporation or its affiliates.
4  * Copyright (C) 2022 Ventana Micro Systems Inc.
5  */
6 
7 #include <linux/bitfield.h>
8 #include <linux/irqchip/riscv-aplic.h>
9 #include <linux/module.h>
10 #include <linux/of.h>
11 #include <linux/of_irq.h>
12 #include <linux/platform_device.h>
13 #include <linux/printk.h>
14 
15 #include "irq-riscv-aplic-main.h"
16 
17 void aplic_irq_unmask(struct irq_data *d)
18 {
19 	struct aplic_priv *priv = irq_data_get_irq_chip_data(d);
20 
21 	writel(d->hwirq, priv->regs + APLIC_SETIENUM);
22 }
23 
24 void aplic_irq_mask(struct irq_data *d)
25 {
26 	struct aplic_priv *priv = irq_data_get_irq_chip_data(d);
27 
28 	writel(d->hwirq, priv->regs + APLIC_CLRIENUM);
29 }
30 
31 int aplic_irq_set_type(struct irq_data *d, unsigned int type)
32 {
33 	struct aplic_priv *priv = irq_data_get_irq_chip_data(d);
34 	void __iomem *sourcecfg;
35 	u32 val = 0;
36 
37 	switch (type) {
38 	case IRQ_TYPE_NONE:
39 		val = APLIC_SOURCECFG_SM_INACTIVE;
40 		break;
41 	case IRQ_TYPE_LEVEL_LOW:
42 		val = APLIC_SOURCECFG_SM_LEVEL_LOW;
43 		break;
44 	case IRQ_TYPE_LEVEL_HIGH:
45 		val = APLIC_SOURCECFG_SM_LEVEL_HIGH;
46 		break;
47 	case IRQ_TYPE_EDGE_FALLING:
48 		val = APLIC_SOURCECFG_SM_EDGE_FALL;
49 		break;
50 	case IRQ_TYPE_EDGE_RISING:
51 		val = APLIC_SOURCECFG_SM_EDGE_RISE;
52 		break;
53 	default:
54 		return -EINVAL;
55 	}
56 
57 	sourcecfg = priv->regs + APLIC_SOURCECFG_BASE;
58 	sourcecfg += (d->hwirq - 1) * sizeof(u32);
59 	writel(val, sourcecfg);
60 
61 	return 0;
62 }
63 
64 int aplic_irqdomain_translate(struct irq_fwspec *fwspec, u32 gsi_base,
65 			      unsigned long *hwirq, unsigned int *type)
66 {
67 	if (WARN_ON(fwspec->param_count < 2))
68 		return -EINVAL;
69 	if (WARN_ON(!fwspec->param[0]))
70 		return -EINVAL;
71 
72 	/* For DT, gsi_base is always zero. */
73 	*hwirq = fwspec->param[0] - gsi_base;
74 	*type = fwspec->param[1] & IRQ_TYPE_SENSE_MASK;
75 
76 	WARN_ON(*type == IRQ_TYPE_NONE);
77 
78 	return 0;
79 }
80 
81 void aplic_init_hw_global(struct aplic_priv *priv, bool msi_mode)
82 {
83 	u32 val;
84 #ifdef CONFIG_RISCV_M_MODE
85 	u32 valh;
86 
87 	if (msi_mode) {
88 		val = lower_32_bits(priv->msicfg.base_ppn);
89 		valh = FIELD_PREP(APLIC_xMSICFGADDRH_BAPPN, upper_32_bits(priv->msicfg.base_ppn));
90 		valh |= FIELD_PREP(APLIC_xMSICFGADDRH_LHXW, priv->msicfg.lhxw);
91 		valh |= FIELD_PREP(APLIC_xMSICFGADDRH_HHXW, priv->msicfg.hhxw);
92 		valh |= FIELD_PREP(APLIC_xMSICFGADDRH_LHXS, priv->msicfg.lhxs);
93 		valh |= FIELD_PREP(APLIC_xMSICFGADDRH_HHXS, priv->msicfg.hhxs);
94 		writel(val, priv->regs + APLIC_xMSICFGADDR);
95 		writel(valh, priv->regs + APLIC_xMSICFGADDRH);
96 	}
97 #endif
98 
99 	/* Setup APLIC domaincfg register */
100 	val = readl(priv->regs + APLIC_DOMAINCFG);
101 	val |= APLIC_DOMAINCFG_IE;
102 	if (msi_mode)
103 		val |= APLIC_DOMAINCFG_DM;
104 	writel(val, priv->regs + APLIC_DOMAINCFG);
105 	if (readl(priv->regs + APLIC_DOMAINCFG) != val)
106 		dev_warn(priv->dev, "unable to write 0x%x in domaincfg\n", val);
107 }
108 
109 static void aplic_init_hw_irqs(struct aplic_priv *priv)
110 {
111 	int i;
112 
113 	/* Disable all interrupts */
114 	for (i = 0; i <= priv->nr_irqs; i += 32)
115 		writel(-1U, priv->regs + APLIC_CLRIE_BASE + (i / 32) * sizeof(u32));
116 
117 	/* Set interrupt type and default priority for all interrupts */
118 	for (i = 1; i <= priv->nr_irqs; i++) {
119 		writel(0, priv->regs + APLIC_SOURCECFG_BASE + (i - 1) * sizeof(u32));
120 		writel(APLIC_DEFAULT_PRIORITY,
121 		       priv->regs + APLIC_TARGET_BASE + (i - 1) * sizeof(u32));
122 	}
123 
124 	/* Clear APLIC domaincfg */
125 	writel(0, priv->regs + APLIC_DOMAINCFG);
126 }
127 
128 int aplic_setup_priv(struct aplic_priv *priv, struct device *dev, void __iomem *regs)
129 {
130 	struct device_node *np = to_of_node(dev->fwnode);
131 	struct of_phandle_args parent;
132 	int rc;
133 
134 	/*
135 	 * Currently, only OF fwnode is supported so extend this
136 	 * function for ACPI support.
137 	 */
138 	if (!np)
139 		return -EINVAL;
140 
141 	/* Save device pointer and register base */
142 	priv->dev = dev;
143 	priv->regs = regs;
144 
145 	/* Find out number of interrupt sources */
146 	rc = of_property_read_u32(np, "riscv,num-sources", &priv->nr_irqs);
147 	if (rc) {
148 		dev_err(dev, "failed to get number of interrupt sources\n");
149 		return rc;
150 	}
151 
152 	/*
153 	 * Find out number of IDCs based on parent interrupts
154 	 *
155 	 * If "msi-parent" property is present then we ignore the
156 	 * APLIC IDCs which forces the APLIC driver to use MSI mode.
157 	 */
158 	if (!of_property_present(np, "msi-parent")) {
159 		while (!of_irq_parse_one(np, priv->nr_idcs, &parent))
160 			priv->nr_idcs++;
161 	}
162 
163 	/* Setup initial state APLIC interrupts */
164 	aplic_init_hw_irqs(priv);
165 
166 	return 0;
167 }
168 
169 static int aplic_probe(struct platform_device *pdev)
170 {
171 	struct device *dev = &pdev->dev;
172 	bool msi_mode = false;
173 	void __iomem *regs;
174 	int rc;
175 
176 	/* Map the MMIO registers */
177 	regs = devm_platform_ioremap_resource(pdev, 0);
178 	if (!regs) {
179 		dev_err(dev, "failed map MMIO registers\n");
180 		return -ENOMEM;
181 	}
182 
183 	/*
184 	 * If msi-parent property is present then setup APLIC MSI
185 	 * mode otherwise setup APLIC direct mode.
186 	 */
187 	msi_mode = of_property_present(to_of_node(dev->fwnode), "msi-parent");
188 	if (msi_mode)
189 		rc = aplic_msi_setup(dev, regs);
190 	else
191 		rc = aplic_direct_setup(dev, regs);
192 	if (rc)
193 		dev_err(dev, "failed to setup APLIC in %s mode\n", msi_mode ? "MSI" : "direct");
194 
195 	return rc;
196 }
197 
198 static const struct of_device_id aplic_match[] = {
199 	{ .compatible = "riscv,aplic" },
200 	{}
201 };
202 
203 static struct platform_driver aplic_driver = {
204 	.driver = {
205 		.name		= "riscv-aplic",
206 		.of_match_table	= aplic_match,
207 	},
208 	.probe = aplic_probe,
209 };
210 builtin_platform_driver(aplic_driver);
211