diff options
author | Chao Xie <chao.xie@marvell.com> | 2012-08-20 02:55:11 (GMT) |
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committer | Mike Turquette <mturquette@linaro.org> | 2012-08-28 21:14:14 (GMT) |
commit | 6b63f023184e34b404b96bb9a8c4ac6692ff3fbd (patch) | |
tree | 1ad367ccdd9dcf6a87d2e30a32b910865ac14f52 /drivers/clk/mmp/clk-apbc.c | |
parent | f9a6aa4303bd15bbdb24d9fe374e4e6850298460 (diff) | |
download | linux-fsl-qoriq-6b63f023184e34b404b96bb9a8c4ac6692ff3fbd.tar.xz |
clk: mmp: add mmp specific clocks
add mmp specific clocks including apbc cloks, apmu clocks,
and pll2, fraction clocks
Signed-off-by: Chao Xie <xiechao.mail@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
Diffstat (limited to 'drivers/clk/mmp/clk-apbc.c')
-rw-r--r-- | drivers/clk/mmp/clk-apbc.c | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/drivers/clk/mmp/clk-apbc.c b/drivers/clk/mmp/clk-apbc.c new file mode 100644 index 0000000..d14120e --- /dev/null +++ b/drivers/clk/mmp/clk-apbc.c @@ -0,0 +1,152 @@ +/* + * mmp APB clock operation source file + * + * Copyright (C) 2012 Marvell + * Chao Xie <xiechao.mail@gmail.com> + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/kernel.h> +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/err.h> +#include <linux/delay.h> +#include <linux/slab.h> + +#include "clk.h" + +/* Common APB clock register bit definitions */ +#define APBC_APBCLK (1 << 0) /* APB Bus Clock Enable */ +#define APBC_FNCLK (1 << 1) /* Functional Clock Enable */ +#define APBC_RST (1 << 2) /* Reset Generation */ +#define APBC_POWER (1 << 7) /* Reset Generation */ + +#define to_clk_apbc(hw) container_of(hw, struct clk_apbc, hw) +struct clk_apbc { + struct clk_hw hw; + void __iomem *base; + unsigned int delay; + unsigned int flags; + spinlock_t *lock; +}; + +static int clk_apbc_prepare(struct clk_hw *hw) +{ + struct clk_apbc *apbc = to_clk_apbc(hw); + unsigned int data; + unsigned long flags = 0; + + /* + * It may share same register as MUX clock, + * and it will impact FNCLK enable. Spinlock is needed + */ + if (apbc->lock) + spin_lock_irqsave(apbc->lock, flags); + + data = readl_relaxed(apbc->base); + if (apbc->flags & APBC_POWER_CTRL) + data |= APBC_POWER; + data |= APBC_FNCLK; + writel_relaxed(data, apbc->base); + + if (apbc->lock) + spin_unlock_irqrestore(apbc->lock, flags); + + udelay(apbc->delay); + + if (apbc->lock) + spin_lock_irqsave(apbc->lock, flags); + + data = readl_relaxed(apbc->base); + data |= APBC_APBCLK; + writel_relaxed(data, apbc->base); + + if (apbc->lock) + spin_unlock_irqrestore(apbc->lock, flags); + + udelay(apbc->delay); + + if (!(apbc->flags & APBC_NO_BUS_CTRL)) { + if (apbc->lock) + spin_lock_irqsave(apbc->lock, flags); + + data = readl_relaxed(apbc->base); + data &= ~APBC_RST; + writel_relaxed(data, apbc->base); + + if (apbc->lock) + spin_unlock_irqrestore(apbc->lock, flags); + } + + return 0; +} + +static void clk_apbc_unprepare(struct clk_hw *hw) +{ + struct clk_apbc *apbc = to_clk_apbc(hw); + unsigned long data; + unsigned long flags = 0; + + if (apbc->lock) + spin_lock_irqsave(apbc->lock, flags); + + data = readl_relaxed(apbc->base); + if (apbc->flags & APBC_POWER_CTRL) + data &= ~APBC_POWER; + data &= ~APBC_FNCLK; + writel_relaxed(data, apbc->base); + + if (apbc->lock) + spin_unlock_irqrestore(apbc->lock, flags); + + udelay(10); + + if (apbc->lock) + spin_lock_irqsave(apbc->lock, flags); + + data = readl_relaxed(apbc->base); + data &= ~APBC_APBCLK; + writel_relaxed(data, apbc->base); + + if (apbc->lock) + spin_unlock_irqrestore(apbc->lock, flags); +} + +struct clk_ops clk_apbc_ops = { + .prepare = clk_apbc_prepare, + .unprepare = clk_apbc_unprepare, +}; + +struct clk *mmp_clk_register_apbc(const char *name, const char *parent_name, + void __iomem *base, unsigned int delay, + unsigned int apbc_flags, spinlock_t *lock) +{ + struct clk_apbc *apbc; + struct clk *clk; + struct clk_init_data init; + + apbc = kzalloc(sizeof(*apbc), GFP_KERNEL); + if (!apbc) + return NULL; + + init.name = name; + init.ops = &clk_apbc_ops; + init.flags = CLK_SET_RATE_PARENT; + init.parent_names = (parent_name ? &parent_name : NULL); + init.num_parents = (parent_name ? 1 : 0); + + apbc->base = base; + apbc->delay = delay; + apbc->flags = apbc_flags; + apbc->lock = lock; + apbc->hw.init = &init; + + clk = clk_register(NULL, &apbc->hw); + if (IS_ERR(clk)) + kfree(apbc); + + return clk; +} |