xref: /openbmc/u-boot/board/synopsys/hsdk/clk-lib.c (revision 85231c08)
1 /*
2  * Copyright (C) 2018 Synopsys, Inc. All rights reserved.
3  * Author: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 #include <clk.h>
9 #include <dm/device.h>
10 
11 #include "clk-lib.h"
12 
13 #define HZ_IN_MHZ	1000000
14 #define ceil(x, y)	({ ulong __x = (x), __y = (y); (__x + __y - 1) / __y; })
15 
16 int soc_clk_ctl(const char *name, ulong *rate, enum clk_ctl_ops ctl)
17 {
18 	int ret;
19 	ulong mhz_rate, priv_rate;
20 	struct clk clk;
21 
22 	/* Dummy fmeas device, just to be able to use standard clk_* api */
23 	struct udevice fmeas = {
24 		.name = "clk-fmeas",
25 		.node = ofnode_path("/clk-fmeas"),
26 	};
27 
28 	ret = clk_get_by_name(&fmeas, name, &clk);
29 	if (ret) {
30 		pr_err("clock '%s' not found, err=%d\n", name, ret);
31 		return ret;
32 	}
33 
34 	if (ctl & CLK_ON) {
35 		ret = clk_enable(&clk);
36 		if (ret && ret != -ENOSYS && ret != -ENOTSUPP)
37 			return ret;
38 	}
39 
40 	if ((ctl & CLK_SET) && rate) {
41 		priv_rate = ctl & CLK_MHZ ? (*rate) * HZ_IN_MHZ : *rate;
42 		ret = clk_set_rate(&clk, priv_rate);
43 		if (ret)
44 			return ret;
45 	}
46 
47 	if (ctl & CLK_OFF) {
48 		ret = clk_disable(&clk);
49 		if (ret) {
50 			pr_err("clock '%s' can't be disabled, err=%d\n", name, ret);
51 			return ret;
52 		}
53 	}
54 
55 	priv_rate = clk_get_rate(&clk);
56 
57 	clk_free(&clk);
58 
59 	mhz_rate = ceil(priv_rate, HZ_IN_MHZ);
60 
61 	if (ctl & CLK_MHZ)
62 		priv_rate = mhz_rate;
63 
64 	if ((ctl & CLK_GET) && rate)
65 		*rate = priv_rate;
66 
67 	if ((ctl & CLK_PRINT) && (ctl & CLK_MHZ))
68 		printf("HSDK: clock '%s' rate %lu MHz\n", name, priv_rate);
69 	else if (ctl & CLK_PRINT)
70 		printf("HSDK: clock '%s' rate %lu Hz\n", name, priv_rate);
71 	else
72 		debug("HSDK: clock '%s' rate %lu MHz\n", name, mhz_rate);
73 
74 	return 0;
75 }
76