1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (C) 2018, Bin Meng <bmeng.cn@gmail.com>
4 *
5 * U-Boot syscon driver for SiFive's Core Local Interruptor (CLINT).
6 * The CLINT block holds memory-mapped control and status registers
7 * associated with software and timer interrupts.
8 */
9
10 #include <common.h>
11 #include <dm.h>
12 #include <regmap.h>
13 #include <syscon.h>
14 #include <asm/io.h>
15 #include <asm/syscon.h>
16 #include <linux/err.h>
17
18 /* MSIP registers */
19 #define MSIP_REG(base, hart) ((ulong)(base) + (hart) * 4)
20 /* mtime compare register */
21 #define MTIMECMP_REG(base, hart) ((ulong)(base) + 0x4000 + (hart) * 8)
22 /* mtime register */
23 #define MTIME_REG(base) ((ulong)(base) + 0xbff8)
24
25 DECLARE_GLOBAL_DATA_PTR;
26
27 #define CLINT_BASE_GET(void) \
28 do { \
29 long *ret; \
30 \
31 if (!gd->arch.clint) { \
32 ret = syscon_get_first_range(RISCV_SYSCON_CLINT); \
33 if (IS_ERR(ret)) \
34 return PTR_ERR(ret); \
35 gd->arch.clint = ret; \
36 } \
37 } while (0)
38
riscv_get_time(u64 * time)39 int riscv_get_time(u64 *time)
40 {
41 CLINT_BASE_GET();
42
43 *time = readq((void __iomem *)MTIME_REG(gd->arch.clint));
44
45 return 0;
46 }
47
riscv_set_timecmp(int hart,u64 cmp)48 int riscv_set_timecmp(int hart, u64 cmp)
49 {
50 CLINT_BASE_GET();
51
52 writeq(cmp, (void __iomem *)MTIMECMP_REG(gd->arch.clint, hart));
53
54 return 0;
55 }
56
riscv_send_ipi(int hart)57 int riscv_send_ipi(int hart)
58 {
59 CLINT_BASE_GET();
60
61 writel(1, (void __iomem *)MSIP_REG(gd->arch.clint, hart));
62
63 return 0;
64 }
65
riscv_clear_ipi(int hart)66 int riscv_clear_ipi(int hart)
67 {
68 CLINT_BASE_GET();
69
70 writel(0, (void __iomem *)MSIP_REG(gd->arch.clint, hart));
71
72 return 0;
73 }
74
riscv_get_ipi(int hart,int * pending)75 int riscv_get_ipi(int hart, int *pending)
76 {
77 CLINT_BASE_GET();
78
79 *pending = readl((void __iomem *)MSIP_REG(gd->arch.clint, hart));
80
81 return 0;
82 }
83
84 static const struct udevice_id sifive_clint_ids[] = {
85 { .compatible = "riscv,clint0", .data = RISCV_SYSCON_CLINT },
86 { }
87 };
88
89 U_BOOT_DRIVER(sifive_clint) = {
90 .name = "sifive_clint",
91 .id = UCLASS_SYSCON,
92 .of_match = sifive_clint_ids,
93 .flags = DM_FLAG_PRE_RELOC,
94 };
95