1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * HSDK SoC Reset Controller driver
4 *
5 * Copyright (C) 2019 Synopsys, Inc. All rights reserved.
6 * Author: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
7 */
8
9 #include <asm/io.h>
10 #include <common.h>
11 #include <dm.h>
12 #include <linux/iopoll.h>
13 #include <reset-uclass.h>
14
15 struct hsdk_rst {
16 void __iomem *regs_ctl;
17 void __iomem *regs_rst;
18 };
19
20 static const u32 rst_map[] = {
21 BIT(16), /* APB_RST */
22 BIT(17), /* AXI_RST */
23 BIT(18), /* ETH_RST */
24 BIT(19), /* USB_RST */
25 BIT(20), /* SDIO_RST */
26 BIT(21), /* HDMI_RST */
27 BIT(22), /* GFX_RST */
28 BIT(25), /* DMAC_RST */
29 BIT(31), /* EBI_RST */
30 };
31
32 #define HSDK_MAX_RESETS ARRAY_SIZE(rst_map)
33
34 #define CGU_SYS_RST_CTRL 0x0
35 #define CGU_IP_SW_RESET 0x0
36 #define CGU_IP_SW_RESET_DELAY_SHIFT 16
37 #define CGU_IP_SW_RESET_DELAY_MASK GENMASK(31, CGU_IP_SW_RESET_DELAY_SHIFT)
38 #define CGU_IP_SW_RESET_DELAY 0
39 #define CGU_IP_SW_RESET_RESET BIT(0)
40 #define SW_RESET_TIMEOUT 10000
41
hsdk_reset_config(struct hsdk_rst * rst,unsigned long id)42 static void hsdk_reset_config(struct hsdk_rst *rst, unsigned long id)
43 {
44 writel(rst_map[id], rst->regs_ctl + CGU_SYS_RST_CTRL);
45 }
46
hsdk_reset_do(struct hsdk_rst * rst)47 static int hsdk_reset_do(struct hsdk_rst *rst)
48 {
49 u32 reg;
50
51 reg = readl(rst->regs_rst + CGU_IP_SW_RESET);
52 reg &= ~CGU_IP_SW_RESET_DELAY_MASK;
53 reg |= CGU_IP_SW_RESET_DELAY << CGU_IP_SW_RESET_DELAY_SHIFT;
54 reg |= CGU_IP_SW_RESET_RESET;
55 writel(reg, rst->regs_rst + CGU_IP_SW_RESET);
56
57 /* wait till reset bit is back to 0 */
58 return readl_poll_timeout(rst->regs_rst + CGU_IP_SW_RESET, reg,
59 !(reg & CGU_IP_SW_RESET_RESET), SW_RESET_TIMEOUT);
60 }
61
hsdk_reset_reset(struct reset_ctl * rst_ctl)62 static int hsdk_reset_reset(struct reset_ctl *rst_ctl)
63 {
64 struct udevice *dev = rst_ctl->dev;
65 struct hsdk_rst *rst = dev_get_priv(dev);
66
67 if (rst_ctl->id >= HSDK_MAX_RESETS)
68 return -EINVAL;
69
70 debug("%s(reset_ctl=%p) (dev=%p, id=%lu)\n", __func__, rst_ctl,
71 rst_ctl->dev, rst_ctl->id);
72
73 hsdk_reset_config(rst, rst_ctl->id);
74 return hsdk_reset_do(rst);
75 }
76
hsdk_reset_noop(struct reset_ctl * rst_ctl)77 static int hsdk_reset_noop(struct reset_ctl *rst_ctl)
78 {
79 return 0;
80 }
81
82 static const struct reset_ops hsdk_reset_ops = {
83 .request = hsdk_reset_noop,
84 .free = hsdk_reset_noop,
85 .rst_assert = hsdk_reset_noop,
86 .rst_deassert = hsdk_reset_reset,
87 };
88
89 static const struct udevice_id hsdk_reset_dt_match[] = {
90 { .compatible = "snps,hsdk-reset" },
91 { },
92 };
93
hsdk_reset_probe(struct udevice * dev)94 static int hsdk_reset_probe(struct udevice *dev)
95 {
96 struct hsdk_rst *rst = dev_get_priv(dev);
97
98 rst->regs_ctl = dev_remap_addr_index(dev, 0);
99 if (!rst->regs_ctl)
100 return -EINVAL;
101
102 rst->regs_rst = dev_remap_addr_index(dev, 1);
103 if (!rst->regs_rst)
104 return -EINVAL;
105
106 return 0;
107 }
108
109 U_BOOT_DRIVER(hsdk_reset) = {
110 .name = "hsdk-reset",
111 .id = UCLASS_RESET,
112 .of_match = hsdk_reset_dt_match,
113 .ops = &hsdk_reset_ops,
114 .probe = hsdk_reset_probe,
115 .priv_auto_alloc_size = sizeof(struct hsdk_rst),
116 };
117