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