1#include <linux/clk.h>
2#include <linux/err.h>
3#include <linux/of.h>
4#include <linux/slab.h>
5#include <linux/spinlock.h>
6#include "clk.h"
7
8DEFINE_SPINLOCK(imx_ccm_lock);
9
10void __init imx_check_clocks(struct clk *clks[], unsigned int count)
11{
12	unsigned i;
13
14	for (i = 0; i < count; i++)
15		if (IS_ERR(clks[i]))
16			pr_err("i.MX clk %u: register failed with %ld\n",
17			       i, PTR_ERR(clks[i]));
18}
19
20static struct clk * __init imx_obtain_fixed_clock_from_dt(const char *name)
21{
22	struct of_phandle_args phandle;
23	struct clk *clk = ERR_PTR(-ENODEV);
24	char *path;
25
26	path = kasprintf(GFP_KERNEL, "/clocks/%s", name);
27	if (!path)
28		return ERR_PTR(-ENOMEM);
29
30	phandle.np = of_find_node_by_path(path);
31	kfree(path);
32
33	if (phandle.np) {
34		clk = of_clk_get_from_provider(&phandle);
35		of_node_put(phandle.np);
36	}
37	return clk;
38}
39
40struct clk * __init imx_obtain_fixed_clock(
41			const char *name, unsigned long rate)
42{
43	struct clk *clk;
44
45	clk = imx_obtain_fixed_clock_from_dt(name);
46	if (IS_ERR(clk))
47		clk = imx_clk_fixed(name, rate);
48	return clk;
49}
50
51/*
52 * This fixups the register CCM_CSCMR1 write value.
53 * The write/read/divider values of the aclk_podf field
54 * of that register have the relationship described by
55 * the following table:
56 *
57 * write value       read value        divider
58 * 3b'000            3b'110            7
59 * 3b'001            3b'111            8
60 * 3b'010            3b'100            5
61 * 3b'011            3b'101            6
62 * 3b'100            3b'010            3
63 * 3b'101            3b'011            4
64 * 3b'110            3b'000            1
65 * 3b'111            3b'001            2(default)
66 *
67 * That's why we do the xor operation below.
68 */
69#define CSCMR1_FIXUP	0x00600000
70
71void imx_cscmr1_fixup(u32 *val)
72{
73	*val ^= CSCMR1_FIXUP;
74	return;
75}
76
77static int imx_keep_uart_clocks __initdata;
78static struct clk ** const *imx_uart_clocks __initdata;
79
80static int __init imx_keep_uart_clocks_param(char *str)
81{
82	imx_keep_uart_clocks = 1;
83
84	return 0;
85}
86__setup_param("earlycon", imx_keep_uart_earlycon,
87	      imx_keep_uart_clocks_param, 0);
88__setup_param("earlyprintk", imx_keep_uart_earlyprintk,
89	      imx_keep_uart_clocks_param, 0);
90
91void __init imx_register_uart_clocks(struct clk ** const clks[])
92{
93	if (imx_keep_uart_clocks) {
94		int i;
95
96		imx_uart_clocks = clks;
97		for (i = 0; imx_uart_clocks[i]; i++)
98			clk_prepare_enable(*imx_uart_clocks[i]);
99	}
100}
101
102static int __init imx_clk_disable_uart(void)
103{
104	if (imx_keep_uart_clocks && imx_uart_clocks) {
105		int i;
106
107		for (i = 0; imx_uart_clocks[i]; i++)
108			clk_disable_unprepare(*imx_uart_clocks[i]);
109	}
110
111	return 0;
112}
113late_initcall_sync(imx_clk_disable_uart);
114