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-rw-r--r--arch/arm/mach-bcmring/clock.c224
1 files changed, 224 insertions, 0 deletions
diff --git a/arch/arm/mach-bcmring/clock.c b/arch/arm/mach-bcmring/clock.c
new file mode 100644
index 000000000000..14bafc38f2dc
--- /dev/null
+++ b/arch/arm/mach-bcmring/clock.c
@@ -0,0 +1,224 @@
+/*****************************************************************************
+* Copyright 2001 - 2009 Broadcom Corporation. All rights reserved.
+*
+* Unless you and Broadcom execute a separate written software license
+* agreement governing use of this software, this software is licensed to you
+* under the terms of the GNU General Public License version 2, available at
+* http://www.broadcom.com/licenses/GPLv2.php (the "GPL").
+*
+* Notwithstanding the above, under no circumstances may you combine this
+* software in any way with any other Broadcom software provided under a
+* license other than the GPL, without Broadcom's express prior written
+* consent.
+*****************************************************************************/
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/list.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/string.h>
+#include <linux/clk.h>
+#include <linux/spinlock.h>
+#include <mach/csp/hw_cfg.h>
+#include <mach/csp/chipcHw_def.h>
+#include <mach/csp/chipcHw_reg.h>
+#include <mach/csp/chipcHw_inline.h>
+
+#include <asm/clkdev.h>
+
+#include "clock.h"
+
+#define clk_is_primary(x) ((x)->type & CLK_TYPE_PRIMARY)
+#define clk_is_pll1(x) ((x)->type & CLK_TYPE_PLL1)
+#define clk_is_pll2(x) ((x)->type & CLK_TYPE_PLL2)
+#define clk_is_programmable(x) ((x)->type & CLK_TYPE_PROGRAMMABLE)
+#define clk_is_bypassable(x) ((x)->type & CLK_TYPE_BYPASSABLE)
+
+#define clk_is_using_xtal(x) ((x)->mode & CLK_MODE_XTAL)
+
+static DEFINE_SPINLOCK(clk_lock);
+
+static void __clk_enable(struct clk *clk)
+{
+ if (!clk)
+ return;
+
+ /* enable parent clock first */
+ if (clk->parent)
+ __clk_enable(clk->parent);
+
+ if (clk->use_cnt++ == 0) {
+ if (clk_is_pll1(clk)) { /* PLL1 */
+ chipcHw_pll1Enable(clk->rate_hz, 0);
+ } else if (clk_is_pll2(clk)) { /* PLL2 */
+ chipcHw_pll2Enable(clk->rate_hz);
+ } else if (clk_is_using_xtal(clk)) { /* source is crystal */
+ if (!clk_is_primary(clk))
+ chipcHw_bypassClockEnable(clk->csp_id);
+ } else { /* source is PLL */
+ chipcHw_setClockEnable(clk->csp_id);
+ }
+ }
+}
+
+int clk_enable(struct clk *clk)
+{
+ unsigned long flags;
+
+ if (!clk)
+ return -EINVAL;
+
+ spin_lock_irqsave(&clk_lock, flags);
+ __clk_enable(clk);
+ spin_unlock_irqrestore(&clk_lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL(clk_enable);
+
+static void __clk_disable(struct clk *clk)
+{
+ if (!clk)
+ return;
+
+ BUG_ON(clk->use_cnt == 0);
+
+ if (--clk->use_cnt == 0) {
+ if (clk_is_pll1(clk)) { /* PLL1 */
+ chipcHw_pll1Disable();
+ } else if (clk_is_pll2(clk)) { /* PLL2 */
+ chipcHw_pll2Disable();
+ } else if (clk_is_using_xtal(clk)) { /* source is crystal */
+ if (!clk_is_primary(clk))
+ chipcHw_bypassClockDisable(clk->csp_id);
+ } else { /* source is PLL */
+ chipcHw_setClockDisable(clk->csp_id);
+ }
+ }
+
+ if (clk->parent)
+ __clk_disable(clk->parent);
+}
+
+void clk_disable(struct clk *clk)
+{
+ unsigned long flags;
+
+ if (!clk)
+ return;
+
+ spin_lock_irqsave(&clk_lock, flags);
+ __clk_disable(clk);
+ spin_unlock_irqrestore(&clk_lock, flags);
+}
+EXPORT_SYMBOL(clk_disable);
+
+unsigned long clk_get_rate(struct clk *clk)
+{
+ if (!clk)
+ return 0;
+
+ return clk->rate_hz;
+}
+EXPORT_SYMBOL(clk_get_rate);
+
+long clk_round_rate(struct clk *clk, unsigned long rate)
+{
+ unsigned long flags;
+ unsigned long actual;
+ unsigned long rate_hz;
+
+ if (!clk)
+ return -EINVAL;
+
+ if (!clk_is_programmable(clk))
+ return -EINVAL;
+
+ if (clk->use_cnt)
+ return -EBUSY;
+
+ spin_lock_irqsave(&clk_lock, flags);
+ actual = clk->parent->rate_hz;
+ rate_hz = min(actual, rate);
+ spin_unlock_irqrestore(&clk_lock, flags);
+
+ return rate_hz;
+}
+EXPORT_SYMBOL(clk_round_rate);
+
+int clk_set_rate(struct clk *clk, unsigned long rate)
+{
+ unsigned long flags;
+ unsigned long actual;
+ unsigned long rate_hz;
+
+ if (!clk)
+ return -EINVAL;
+
+ if (!clk_is_programmable(clk))
+ return -EINVAL;
+
+ if (clk->use_cnt)
+ return -EBUSY;
+
+ spin_lock_irqsave(&clk_lock, flags);
+ actual = clk->parent->rate_hz;
+ rate_hz = min(actual, rate);
+ rate_hz = chipcHw_setClockFrequency(clk->csp_id, rate_hz);
+ clk->rate_hz = rate_hz;
+ spin_unlock_irqrestore(&clk_lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL(clk_set_rate);
+
+struct clk *clk_get_parent(struct clk *clk)
+{
+ if (!clk)
+ return NULL;
+
+ return clk->parent;
+}
+EXPORT_SYMBOL(clk_get_parent);
+
+int clk_set_parent(struct clk *clk, struct clk *parent)
+{
+ unsigned long flags;
+ struct clk *old_parent;
+
+ if (!clk || !parent)
+ return -EINVAL;
+
+ if (!clk_is_primary(parent) || !clk_is_bypassable(clk))
+ return -EINVAL;
+
+ /* if more than one user, parent is not allowed */
+ if (clk->use_cnt > 1)
+ return -EBUSY;
+
+ if (clk->parent == parent)
+ return 0;
+
+ spin_lock_irqsave(&clk_lock, flags);
+ old_parent = clk->parent;
+ clk->parent = parent;
+ if (clk_is_using_xtal(parent))
+ clk->mode |= CLK_MODE_XTAL;
+ else
+ clk->mode &= (~CLK_MODE_XTAL);
+
+ /* if clock is active */
+ if (clk->use_cnt != 0) {
+ clk->use_cnt--;
+ /* enable clock with the new parent */
+ __clk_enable(clk);
+ /* disable the old parent */
+ __clk_disable(old_parent);
+ }
+ spin_unlock_irqrestore(&clk_lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL(clk_set_parent);