1/*
2 * OMAP2xxx osc_clk-specific clock code
3 *
4 * Copyright (C) 2005-2008 Texas Instruments, Inc.
5 * Copyright (C) 2004-2010 Nokia Corporation
6 *
7 * Contacts:
8 * Richard Woodruff <r-woodruff2@ti.com>
9 * Paul Walmsley
10 *
11 * Based on earlier work by Tuukka Tikkanen, Tony Lindgren,
12 * Gordon McNutt and RidgeRun, Inc.
13 *
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License version 2 as
16 * published by the Free Software Foundation.
17 */
18#undef DEBUG
19
20#include <linux/module.h>
21#include <linux/kernel.h>
22#include <linux/errno.h>
23#include <linux/clk.h>
24#include <linux/io.h>
25
26#include <plat/clock.h>
27
28#include "clock.h"
29#include "clock2xxx.h"
30#include "prm2xxx_3xxx.h"
31#include "prm-regbits-24xx.h"
32
33/*
34 * XXX This does not actually enable the osc_ck, since the osc_ck must
35 * be running for this function to be called.  Instead, this function
36 * is used to disable an autoidle mode on the osc_ck.  The existing
37 * clk_enable/clk_disable()-based usecounting for osc_ck should be
38 * replaced with autoidle-based usecounting.
39 */
40static int omap2_enable_osc_ck(struct clk *clk)
41{
42	u32 pcc;
43
44	pcc = __raw_readl(prcm_clksrc_ctrl);
45
46	__raw_writel(pcc & ~OMAP_AUTOEXTCLKMODE_MASK, prcm_clksrc_ctrl);
47
48	return 0;
49}
50
51/*
52 * XXX This does not actually disable the osc_ck, since doing so would
53 * immediately halt the system.  Instead, this function is used to
54 * enable an autoidle mode on the osc_ck.  The existing
55 * clk_enable/clk_disable()-based usecounting for osc_ck should be
56 * replaced with autoidle-based usecounting.
57 */
58static void omap2_disable_osc_ck(struct clk *clk)
59{
60	u32 pcc;
61
62	pcc = __raw_readl(prcm_clksrc_ctrl);
63
64	__raw_writel(pcc | OMAP_AUTOEXTCLKMODE_MASK, prcm_clksrc_ctrl);
65}
66
67const struct clkops clkops_oscck = {
68	.enable		= omap2_enable_osc_ck,
69	.disable	= omap2_disable_osc_ck,
70};
71
72unsigned long omap2_osc_clk_recalc(struct clk *clk)
73{
74	return omap2xxx_get_apll_clkin() * omap2xxx_get_sysclkdiv();
75}
76
77