1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright 2019 Broadcom.
4  */
5 #include <common.h>
6 #include <dm.h>
7 #include <regmap.h>
8 #include <syscon.h>
9 #include <asm/gic.h>
10 #include <asm/gic-v3.h>
11 #include <asm/io.h>
12 #include <linux/bitops.h>
13 #include <linux/sizes.h>
14 
15 static u32 lpi_id_bits;
16 
17 #define LPI_NRBITS		lpi_id_bits
18 #define LPI_PROPBASE_SZ		ALIGN(BIT(LPI_NRBITS), SZ_64K)
19 #define LPI_PENDBASE_SZ		ALIGN(BIT(LPI_NRBITS) / 8, SZ_64K)
20 
21 /* Number of GIC re-distributors */
22 #define MAX_GIC_REDISTRIBUTORS	8
23 
24 /*
25  * gic_v3_its_priv - gic details
26  *
27  * @gicd_base: gicd base address
28  * @gicr_base: gicr base address
29  * @lpi_base: gic lpi base address
30  * @num_redist: number of gic re-distributors
31  */
32 struct gic_v3_its_priv {
33 	ulong gicd_base;
34 	ulong gicr_base;
35 	ulong lpi_base;
36 	u32 num_redist;
37 };
38 
gic_v3_its_get_gic_addr(struct gic_v3_its_priv * priv)39 static int gic_v3_its_get_gic_addr(struct gic_v3_its_priv *priv)
40 {
41 	struct udevice *dev;
42 	fdt_addr_t addr;
43 	int ret;
44 
45 	ret = uclass_get_device_by_driver(UCLASS_IRQ,
46 					  DM_DRIVER_GET(arm_gic_v3_its), &dev);
47 	if (ret) {
48 		pr_err("%s: failed to get %s irq device\n", __func__,
49 		       DM_DRIVER_GET(arm_gic_v3_its)->name);
50 		return ret;
51 	}
52 
53 	addr = dev_read_addr_index(dev, 0);
54 	if (addr == FDT_ADDR_T_NONE) {
55 		pr_err("%s: failed to get GICD address\n", __func__);
56 		return -EINVAL;
57 	}
58 	priv->gicd_base = addr;
59 
60 	addr = dev_read_addr_index(dev, 1);
61 	if (addr == FDT_ADDR_T_NONE) {
62 		pr_err("%s: failed to get GICR address\n", __func__);
63 		return -EINVAL;
64 	}
65 	priv->gicr_base = addr;
66 
67 	return 0;
68 }
69 
gic_v3_its_get_gic_lpi_addr(struct gic_v3_its_priv * priv)70 static int gic_v3_its_get_gic_lpi_addr(struct gic_v3_its_priv *priv)
71 {
72 	struct regmap *regmap;
73 	struct udevice *dev;
74 	int ret;
75 
76 	ret = uclass_get_device_by_driver(UCLASS_SYSCON,
77 					  DM_DRIVER_GET(gic_lpi_syscon), &dev);
78 	if (ret) {
79 		pr_err("%s: failed to get %s syscon device\n", __func__,
80 		       DM_DRIVER_GET(gic_lpi_syscon)->name);
81 		return ret;
82 	}
83 
84 	regmap = syscon_get_regmap(dev);
85 	if (!regmap) {
86 		pr_err("%s: failed to regmap for %s syscon device\n", __func__,
87 		       DM_DRIVER_GET(gic_lpi_syscon)->name);
88 		return -ENODEV;
89 	}
90 	priv->lpi_base = regmap->ranges[0].start;
91 
92 	priv->num_redist = dev_read_u32_default(dev, "max-gic-redistributors",
93 						MAX_GIC_REDISTRIBUTORS);
94 
95 	return 0;
96 }
97 
98 /*
99  * Program the GIC LPI configuration tables for all
100  * the re-distributors and enable the LPI table
101  */
gic_lpi_tables_init(void)102 int gic_lpi_tables_init(void)
103 {
104 	struct gic_v3_its_priv priv;
105 	u32 gicd_typer;
106 	u64 val;
107 	u64 tmp;
108 	int i;
109 	u64 redist_lpi_base;
110 	u64 pend_base;
111 
112 	if (gic_v3_its_get_gic_addr(&priv))
113 		return -EINVAL;
114 
115 	if (gic_v3_its_get_gic_lpi_addr(&priv))
116 		return -EINVAL;
117 
118 	gicd_typer = readl((uintptr_t)(priv.gicd_base + GICD_TYPER));
119 	/* GIC support for Locality specific peripheral interrupts (LPI's) */
120 	if (!(gicd_typer & GICD_TYPER_LPIS)) {
121 		pr_err("GIC implementation does not support LPI's\n");
122 		return -EINVAL;
123 	}
124 
125 	/*
126 	 * Check for LPI is disabled for all the redistributors.
127 	 * Once the LPI table is enabled, can not program the
128 	 * LPI configuration tables again, unless the GIC is reset.
129 	 */
130 	for (i = 0; i < priv.num_redist; i++) {
131 		u32 offset = i * GIC_REDISTRIBUTOR_OFFSET;
132 
133 		if ((readl((uintptr_t)(priv.gicr_base + offset))) &
134 		    GICR_CTLR_ENABLE_LPIS) {
135 			pr_err("Re-Distributor %d LPI is already enabled\n",
136 			       i);
137 			return -EINVAL;
138 		}
139 	}
140 
141 	/* lpi_id_bits to get LPI_PENDBASE_SZ and LPi_PROPBASE_SZ */
142 	lpi_id_bits = min_t(u32, GICD_TYPER_ID_BITS(gicd_typer),
143 			    ITS_MAX_LPI_NRBITS);
144 
145 	/* Set PropBase */
146 	val = (priv.lpi_base |
147 	       GICR_PROPBASER_INNERSHAREABLE |
148 	       GICR_PROPBASER_RAWAWB |
149 	       ((LPI_NRBITS - 1) & GICR_PROPBASER_IDBITS_MASK));
150 
151 	writeq(val, (uintptr_t)(priv.gicr_base + GICR_PROPBASER));
152 	tmp = readl((uintptr_t)(priv.gicr_base + GICR_PROPBASER));
153 	if ((tmp ^ val) & GICR_PROPBASER_SHAREABILITY_MASK) {
154 		if (!(tmp & GICR_PROPBASER_SHAREABILITY_MASK)) {
155 			val &= ~(GICR_PROPBASER_SHAREABILITY_MASK |
156 				GICR_PROPBASER_CACHEABILITY_MASK);
157 			val |= GICR_PROPBASER_NC;
158 			writeq(val,
159 			       (uintptr_t)(priv.gicr_base + GICR_PROPBASER));
160 		}
161 	}
162 
163 	redist_lpi_base = priv.lpi_base + LPI_PROPBASE_SZ;
164 
165 	pend_base = priv.gicr_base + GICR_PENDBASER;
166 	for (i = 0; i < priv.num_redist; i++) {
167 		u32 offset = i * GIC_REDISTRIBUTOR_OFFSET;
168 
169 		val = ((redist_lpi_base + (i * LPI_PENDBASE_SZ)) |
170 			GICR_PENDBASER_INNERSHAREABLE |
171 			GICR_PENDBASER_RAWAWB);
172 
173 		writeq(val, (uintptr_t)(pend_base + offset));
174 		tmp = readq((uintptr_t)(pend_base + offset));
175 		if (!(tmp & GICR_PENDBASER_SHAREABILITY_MASK)) {
176 			val &= ~(GICR_PENDBASER_SHAREABILITY_MASK |
177 				 GICR_PENDBASER_CACHEABILITY_MASK);
178 			val |= GICR_PENDBASER_NC;
179 			writeq(val, (uintptr_t)(pend_base + offset));
180 		}
181 
182 		/* Enable LPI for the redistributor */
183 		writel(GICR_CTLR_ENABLE_LPIS,
184 		       (uintptr_t)(priv.gicr_base + offset));
185 	}
186 
187 	return 0;
188 }
189 
190 static const struct udevice_id gic_v3_its_ids[] = {
191 	{ .compatible = "arm,gic-v3" },
192 	{}
193 };
194 
195 U_BOOT_DRIVER(arm_gic_v3_its) = {
196 	.name		= "gic-v3",
197 	.id		= UCLASS_IRQ,
198 	.of_match	= gic_v3_its_ids,
199 };
200 
201 static const struct udevice_id gic_lpi_syscon_ids[] = {
202 	{ .compatible = "gic-lpi-base" },
203 	{}
204 };
205 
206 U_BOOT_DRIVER(gic_lpi_syscon) = {
207 	.name		= "gic-lpi-base",
208 	.id		= UCLASS_SYSCON,
209 	.of_match	= gic_lpi_syscon_ids,
210 };
211