1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright 2020 ASPEED Technology Inc.
4 */
5
6 #include <dm.h>
7 #include <log.h>
8 #include <misc.h>
9 #include <reset.h>
10 #include <reset-uclass.h>
11 #include <linux/err.h>
12 #include <asm/io.h>
13 #include <asm/arch/scu_ast2600.h>
14
15 struct ast2600_reset_priv {
16 struct ast2600_scu *scu;
17 };
18
ast2600_reset_assert(struct reset_ctl * reset_ctl)19 static int ast2600_reset_assert(struct reset_ctl *reset_ctl)
20 {
21 struct ast2600_reset_priv *priv = dev_get_priv(reset_ctl->dev);
22 struct ast2600_scu *scu = priv->scu;
23
24 debug("%s: reset_ctl->id: %lu\n", __func__, reset_ctl->id);
25
26 if (reset_ctl->id < 32)
27 writel(BIT(reset_ctl->id), &scu->modrst_ctrl1);
28 else
29 writel(BIT(reset_ctl->id - 32), &scu->modrst_ctrl2);
30
31 return 0;
32 }
33
ast2600_reset_deassert(struct reset_ctl * reset_ctl)34 static int ast2600_reset_deassert(struct reset_ctl *reset_ctl)
35 {
36 struct ast2600_reset_priv *priv = dev_get_priv(reset_ctl->dev);
37 struct ast2600_scu *scu = priv->scu;
38
39 debug("%s: reset_ctl->id: %lu\n", __func__, reset_ctl->id);
40
41 if (reset_ctl->id < 32)
42 writel(BIT(reset_ctl->id), &scu->modrst_clr1);
43 else
44 writel(BIT(reset_ctl->id - 32), &scu->modrst_clr2);
45
46 return 0;
47 }
48
ast2600_reset_status(struct reset_ctl * reset_ctl)49 static int ast2600_reset_status(struct reset_ctl *reset_ctl)
50 {
51 struct ast2600_reset_priv *priv = dev_get_priv(reset_ctl->dev);
52 struct ast2600_scu *scu = priv->scu;
53 int status;
54
55 debug("%s: reset_ctl->id: %lu\n", __func__, reset_ctl->id);
56
57 if (reset_ctl->id < 32)
58 status = BIT(reset_ctl->id) & readl(&scu->modrst_ctrl1);
59 else
60 status = BIT(reset_ctl->id - 32) & readl(&scu->modrst_ctrl2);
61
62 return !!status;
63 }
64
ast2600_reset_probe(struct udevice * dev)65 static int ast2600_reset_probe(struct udevice *dev)
66 {
67 int rc;
68 struct ast2600_reset_priv *priv = dev_get_priv(dev);
69 struct udevice *scu_dev;
70
71 /* get SCU base from clock device */
72 rc = uclass_get_device_by_driver(UCLASS_CLK,
73 DM_DRIVER_GET(aspeed_ast2600_scu), &scu_dev);
74 if (rc) {
75 debug("%s: clock device not found, rc=%d\n", __func__, rc);
76 return rc;
77 }
78
79 priv->scu = devfdt_get_addr_ptr(scu_dev);
80 if (IS_ERR_OR_NULL(priv->scu)) {
81 debug("%s: invalid SCU base pointer\n", __func__);
82 return PTR_ERR(priv->scu);
83 }
84
85 return 0;
86 }
87
88 static const struct udevice_id ast2600_reset_ids[] = {
89 { .compatible = "aspeed,ast2600-reset" },
90 { }
91 };
92
93 struct reset_ops ast2600_reset_ops = {
94 .rst_assert = ast2600_reset_assert,
95 .rst_deassert = ast2600_reset_deassert,
96 .rst_status = ast2600_reset_status,
97 };
98
99 U_BOOT_DRIVER(ast2600_reset) = {
100 .name = "ast2600_reset",
101 .id = UCLASS_RESET,
102 .of_match = ast2600_reset_ids,
103 .probe = ast2600_reset_probe,
104 .ops = &ast2600_reset_ops,
105 .priv_auto = sizeof(struct ast2600_reset_priv),
106 };
107