diff options
Diffstat (limited to 'drivers/clk/socfpga/clk-periph.c')
| -rw-r--r-- | drivers/clk/socfpga/clk-periph.c | 110 | 
1 files changed, 110 insertions, 0 deletions
diff --git a/drivers/clk/socfpga/clk-periph.c b/drivers/clk/socfpga/clk-periph.c new file mode 100644 index 00000000000..46531c34ec9 --- /dev/null +++ b/drivers/clk/socfpga/clk-periph.c @@ -0,0 +1,110 @@ +/* + *  Copyright 2011-2012 Calxeda, Inc. + *  Copyright (C) 2012-2013 Altera Corporation <www.altera.com> + * + * 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. + * + * Based from clk-highbank.c + * + */ +#include <linux/clk.h> +#include <linux/clkdev.h> +#include <linux/clk-provider.h> +#include <linux/io.h> +#include <linux/of.h> + +#include "clk.h" + +#define to_socfpga_periph_clk(p) container_of(p, struct socfpga_periph_clk, hw.hw) + +static unsigned long clk_periclk_recalc_rate(struct clk_hw *hwclk, +					     unsigned long parent_rate) +{ +	struct socfpga_periph_clk *socfpgaclk = to_socfpga_periph_clk(hwclk); +	u32 div, val; + +	if (socfpgaclk->fixed_div) { +		div = socfpgaclk->fixed_div; +	} else { +		if (socfpgaclk->div_reg) { +			val = readl(socfpgaclk->div_reg) >> socfpgaclk->shift; +			val &= div_mask(socfpgaclk->width); +			parent_rate /= (val + 1); +		} +		div = ((readl(socfpgaclk->hw.reg) & 0x1ff) + 1); +	} + +	return parent_rate / div; +} + +static const struct clk_ops periclk_ops = { +	.recalc_rate = clk_periclk_recalc_rate, +}; + +static __init void __socfpga_periph_init(struct device_node *node, +	const struct clk_ops *ops) +{ +	u32 reg; +	struct clk *clk; +	struct socfpga_periph_clk *periph_clk; +	const char *clk_name = node->name; +	const char *parent_name; +	struct clk_init_data init; +	int rc; +	u32 fixed_div; +	u32 div_reg[3]; + +	of_property_read_u32(node, "reg", ®); + +	periph_clk = kzalloc(sizeof(*periph_clk), GFP_KERNEL); +	if (WARN_ON(!periph_clk)) +		return; + +	periph_clk->hw.reg = clk_mgr_base_addr + reg; + +	rc = of_property_read_u32_array(node, "div-reg", div_reg, 3); +	if (!rc) { +		periph_clk->div_reg = clk_mgr_base_addr + div_reg[0]; +		periph_clk->shift = div_reg[1]; +		periph_clk->width = div_reg[2]; +	} else { +		periph_clk->div_reg = 0; +	} + +	rc = of_property_read_u32(node, "fixed-divider", &fixed_div); +	if (rc) +		periph_clk->fixed_div = 0; +	else +		periph_clk->fixed_div = fixed_div; + +	of_property_read_string(node, "clock-output-names", &clk_name); + +	init.name = clk_name; +	init.ops = ops; +	init.flags = 0; +	parent_name = of_clk_get_parent_name(node, 0); +	init.parent_names = &parent_name; +	init.num_parents = 1; + +	periph_clk->hw.hw.init = &init; + +	clk = clk_register(NULL, &periph_clk->hw.hw); +	if (WARN_ON(IS_ERR(clk))) { +		kfree(periph_clk); +		return; +	} +	rc = of_clk_add_provider(node, of_clk_src_simple_get, clk); +} + +void __init socfpga_periph_init(struct device_node *node) +{ +	__socfpga_periph_init(node, &periclk_ops); +}  | 
