xref: /openbmc/linux/drivers/clk/ti/clkt_iclk.c (revision f3539c12)
1 /*
2  * OMAP2/3 interface clock control
3  *
4  * Copyright (C) 2011 Nokia Corporation
5  * Paul Walmsley
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #undef DEBUG
12 
13 #include <linux/kernel.h>
14 #include <linux/clk-provider.h>
15 #include <linux/io.h>
16 #include <linux/clk/ti.h>
17 
18 #include "clock.h"
19 
20 /* Register offsets */
21 #define OMAP24XX_CM_FCLKEN2		0x04
22 #define CM_AUTOIDLE			0x30
23 #define CM_ICLKEN			0x10
24 #define CM_IDLEST			0x20
25 
26 #define OMAP24XX_CM_IDLEST_VAL		0
27 
28 /* Private functions */
29 
30 /* XXX */
31 void omap2_clkt_iclk_allow_idle(struct clk_hw_omap *clk)
32 {
33 	u32 v;
34 	void __iomem *r;
35 
36 	r = (__force void __iomem *)
37 		((__force u32)clk->enable_reg ^ (CM_AUTOIDLE ^ CM_ICLKEN));
38 
39 	v = ti_clk_ll_ops->clk_readl(r);
40 	v |= (1 << clk->enable_bit);
41 	ti_clk_ll_ops->clk_writel(v, r);
42 }
43 
44 /* XXX */
45 void omap2_clkt_iclk_deny_idle(struct clk_hw_omap *clk)
46 {
47 	u32 v;
48 	void __iomem *r;
49 
50 	r = (__force void __iomem *)
51 		((__force u32)clk->enable_reg ^ (CM_AUTOIDLE ^ CM_ICLKEN));
52 
53 	v = ti_clk_ll_ops->clk_readl(r);
54 	v &= ~(1 << clk->enable_bit);
55 	ti_clk_ll_ops->clk_writel(v, r);
56 }
57 
58 /**
59  * omap2430_clk_i2chs_find_idlest - return CM_IDLEST info for 2430 I2CHS
60  * @clk: struct clk * being enabled
61  * @idlest_reg: void __iomem ** to store CM_IDLEST reg address into
62  * @idlest_bit: pointer to a u8 to store the CM_IDLEST bit shift into
63  * @idlest_val: pointer to a u8 to store the CM_IDLEST indicator
64  *
65  * OMAP2430 I2CHS CM_IDLEST bits are in CM_IDLEST1_CORE, but the
66  * CM_*CLKEN bits are in CM_{I,F}CLKEN2_CORE.  This custom function
67  * passes back the correct CM_IDLEST register address for I2CHS
68  * modules.  No return value.
69  */
70 static void omap2430_clk_i2chs_find_idlest(struct clk_hw_omap *clk,
71 					   void __iomem **idlest_reg,
72 					   u8 *idlest_bit,
73 					   u8 *idlest_val)
74 {
75 	u32 r;
76 
77 	r = ((__force u32)clk->enable_reg ^ (OMAP24XX_CM_FCLKEN2 ^ CM_IDLEST));
78 	*idlest_reg = (__force void __iomem *)r;
79 	*idlest_bit = clk->enable_bit;
80 	*idlest_val = OMAP24XX_CM_IDLEST_VAL;
81 }
82 
83 /* Public data */
84 
85 const struct clk_hw_omap_ops clkhwops_iclk = {
86 	.allow_idle	= omap2_clkt_iclk_allow_idle,
87 	.deny_idle	= omap2_clkt_iclk_deny_idle,
88 };
89 
90 const struct clk_hw_omap_ops clkhwops_iclk_wait = {
91 	.allow_idle	= omap2_clkt_iclk_allow_idle,
92 	.deny_idle	= omap2_clkt_iclk_deny_idle,
93 	.find_idlest	= omap2_clk_dflt_find_idlest,
94 	.find_companion	= omap2_clk_dflt_find_companion,
95 };
96 
97 /* 2430 I2CHS has non-standard IDLEST register */
98 const struct clk_hw_omap_ops clkhwops_omap2430_i2chs_wait = {
99 	.find_idlest	= omap2430_clk_i2chs_find_idlest,
100 	.find_companion	= omap2_clk_dflt_find_companion,
101 };
102