xref: /openbmc/linux/drivers/clk/ti/clkt_iclk.c (revision e15a5365)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * OMAP2/3 interface clock control
4  *
5  * Copyright (C) 2011 Nokia Corporation
6  * Paul Walmsley
7  */
8 #undef DEBUG
9 
10 #include <linux/kernel.h>
11 #include <linux/clk-provider.h>
12 #include <linux/io.h>
13 #include <linux/clk/ti.h>
14 
15 #include "clock.h"
16 
17 /* Register offsets */
18 #define OMAP24XX_CM_FCLKEN2		0x04
19 #define CM_AUTOIDLE			0x30
20 #define CM_ICLKEN			0x10
21 #define CM_IDLEST			0x20
22 
23 #define OMAP24XX_CM_IDLEST_VAL		0
24 
25 /* Private functions */
26 
27 /* XXX */
28 void omap2_clkt_iclk_allow_idle(struct clk_hw_omap *clk)
29 {
30 	u32 v;
31 	struct clk_omap_reg r;
32 
33 	memcpy(&r, &clk->enable_reg, sizeof(r));
34 	r.offset ^= (CM_AUTOIDLE ^ CM_ICLKEN);
35 
36 	v = ti_clk_ll_ops->clk_readl(&r);
37 	v |= (1 << clk->enable_bit);
38 	ti_clk_ll_ops->clk_writel(v, &r);
39 }
40 
41 /* XXX */
42 void omap2_clkt_iclk_deny_idle(struct clk_hw_omap *clk)
43 {
44 	u32 v;
45 	struct clk_omap_reg r;
46 
47 	memcpy(&r, &clk->enable_reg, sizeof(r));
48 
49 	r.offset ^= (CM_AUTOIDLE ^ CM_ICLKEN);
50 
51 	v = ti_clk_ll_ops->clk_readl(&r);
52 	v &= ~(1 << clk->enable_bit);
53 	ti_clk_ll_ops->clk_writel(v, &r);
54 }
55 
56 /**
57  * omap2430_clk_i2chs_find_idlest - return CM_IDLEST info for 2430 I2CHS
58  * @clk: struct clk * being enabled
59  * @idlest_reg: void __iomem ** to store CM_IDLEST reg address into
60  * @idlest_bit: pointer to a u8 to store the CM_IDLEST bit shift into
61  * @idlest_val: pointer to a u8 to store the CM_IDLEST indicator
62  *
63  * OMAP2430 I2CHS CM_IDLEST bits are in CM_IDLEST1_CORE, but the
64  * CM_*CLKEN bits are in CM_{I,F}CLKEN2_CORE.  This custom function
65  * passes back the correct CM_IDLEST register address for I2CHS
66  * modules.  No return value.
67  */
68 static void omap2430_clk_i2chs_find_idlest(struct clk_hw_omap *clk,
69 					   struct clk_omap_reg *idlest_reg,
70 					   u8 *idlest_bit,
71 					   u8 *idlest_val)
72 {
73 	memcpy(idlest_reg, &clk->enable_reg, sizeof(*idlest_reg));
74 	idlest_reg->offset ^= (OMAP24XX_CM_FCLKEN2 ^ CM_IDLEST);
75 	*idlest_bit = clk->enable_bit;
76 	*idlest_val = OMAP24XX_CM_IDLEST_VAL;
77 }
78 
79 /* Public data */
80 
81 const struct clk_hw_omap_ops clkhwops_iclk = {
82 	.allow_idle	= omap2_clkt_iclk_allow_idle,
83 	.deny_idle	= omap2_clkt_iclk_deny_idle,
84 };
85 
86 const struct clk_hw_omap_ops clkhwops_iclk_wait = {
87 	.allow_idle	= omap2_clkt_iclk_allow_idle,
88 	.deny_idle	= omap2_clkt_iclk_deny_idle,
89 	.find_idlest	= omap2_clk_dflt_find_idlest,
90 	.find_companion	= omap2_clk_dflt_find_companion,
91 };
92 
93 /* 2430 I2CHS has non-standard IDLEST register */
94 const struct clk_hw_omap_ops clkhwops_omap2430_i2chs_wait = {
95 	.find_idlest	= omap2430_clk_i2chs_find_idlest,
96 	.find_companion	= omap2_clk_dflt_find_companion,
97 };
98