diff options
Diffstat (limited to 'kernel/drivers/clk/hisilicon/clkgate-separated.c')
-rw-r--r-- | kernel/drivers/clk/hisilicon/clkgate-separated.c | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/kernel/drivers/clk/hisilicon/clkgate-separated.c b/kernel/drivers/clk/hisilicon/clkgate-separated.c new file mode 100644 index 000000000..b03d5a724 --- /dev/null +++ b/kernel/drivers/clk/hisilicon/clkgate-separated.c @@ -0,0 +1,130 @@ +/* + * Hisilicon clock separated gate driver + * + * Copyright (c) 2012-2013 Hisilicon Limited. + * Copyright (c) 2012-2013 Linaro Limited. + * + * Author: Haojian Zhuang <haojian.zhuang@linaro.org> + * Xin Li <li.xin@linaro.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + * + */ + +#include <linux/kernel.h> +#include <linux/clk-provider.h> +#include <linux/clkdev.h> +#include <linux/io.h> +#include <linux/slab.h> +#include <linux/clk.h> + +#include "clk.h" + +/* clock separated gate register offset */ +#define CLKGATE_SEPERATED_ENABLE 0x0 +#define CLKGATE_SEPERATED_DISABLE 0x4 +#define CLKGATE_SEPERATED_STATUS 0x8 + +struct clkgate_separated { + struct clk_hw hw; + void __iomem *enable; /* enable register */ + u8 bit_idx; /* bits in enable/disable register */ + u8 flags; + spinlock_t *lock; +}; + +static int clkgate_separated_enable(struct clk_hw *hw) +{ + struct clkgate_separated *sclk; + unsigned long flags = 0; + u32 reg; + + sclk = container_of(hw, struct clkgate_separated, hw); + if (sclk->lock) + spin_lock_irqsave(sclk->lock, flags); + reg = BIT(sclk->bit_idx); + writel_relaxed(reg, sclk->enable); + readl_relaxed(sclk->enable + CLKGATE_SEPERATED_STATUS); + if (sclk->lock) + spin_unlock_irqrestore(sclk->lock, flags); + return 0; +} + +static void clkgate_separated_disable(struct clk_hw *hw) +{ + struct clkgate_separated *sclk; + unsigned long flags = 0; + u32 reg; + + sclk = container_of(hw, struct clkgate_separated, hw); + if (sclk->lock) + spin_lock_irqsave(sclk->lock, flags); + reg = BIT(sclk->bit_idx); + writel_relaxed(reg, sclk->enable + CLKGATE_SEPERATED_DISABLE); + readl_relaxed(sclk->enable + CLKGATE_SEPERATED_STATUS); + if (sclk->lock) + spin_unlock_irqrestore(sclk->lock, flags); +} + +static int clkgate_separated_is_enabled(struct clk_hw *hw) +{ + struct clkgate_separated *sclk; + u32 reg; + + sclk = container_of(hw, struct clkgate_separated, hw); + reg = readl_relaxed(sclk->enable + CLKGATE_SEPERATED_STATUS); + reg &= BIT(sclk->bit_idx); + + return reg ? 1 : 0; +} + +static struct clk_ops clkgate_separated_ops = { + .enable = clkgate_separated_enable, + .disable = clkgate_separated_disable, + .is_enabled = clkgate_separated_is_enabled, +}; + +struct clk *hisi_register_clkgate_sep(struct device *dev, const char *name, + const char *parent_name, + unsigned long flags, + void __iomem *reg, u8 bit_idx, + u8 clk_gate_flags, spinlock_t *lock) +{ + struct clkgate_separated *sclk; + struct clk *clk; + struct clk_init_data init; + + sclk = kzalloc(sizeof(*sclk), GFP_KERNEL); + if (!sclk) { + pr_err("%s: fail to allocate separated gated clk\n", __func__); + return ERR_PTR(-ENOMEM); + } + + init.name = name; + init.ops = &clkgate_separated_ops; + init.flags = flags | CLK_IS_BASIC; + init.parent_names = (parent_name ? &parent_name : NULL); + init.num_parents = (parent_name ? 1 : 0); + + sclk->enable = reg + CLKGATE_SEPERATED_ENABLE; + sclk->bit_idx = bit_idx; + sclk->flags = clk_gate_flags; + sclk->hw.init = &init; + + clk = clk_register(dev, &sclk->hw); + if (IS_ERR(clk)) + kfree(sclk); + return clk; +} |