From e5fd91f1ef340da553f7a79da9540c3db711c937 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Tue, 8 Sep 2015 01:01:14 -0300 Subject: Linux-libre 4.2-gnu --- drivers/clk/bcm/clk-iproc-asiu.c | 272 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 272 insertions(+) create mode 100644 drivers/clk/bcm/clk-iproc-asiu.c (limited to 'drivers/clk/bcm/clk-iproc-asiu.c') diff --git a/drivers/clk/bcm/clk-iproc-asiu.c b/drivers/clk/bcm/clk-iproc-asiu.c new file mode 100644 index 000000000..f630e1bbd --- /dev/null +++ b/drivers/clk/bcm/clk-iproc-asiu.c @@ -0,0 +1,272 @@ +/* + * Copyright (C) 2014 Broadcom Corporation + * + * 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 version 2. + * + * This program is distributed "as is" WITHOUT ANY WARRANTY of any + * kind, whether express or implied; without even the implied warranty + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include "clk-iproc.h" + +struct iproc_asiu; + +struct iproc_asiu_clk { + struct clk_hw hw; + const char *name; + struct iproc_asiu *asiu; + unsigned long rate; + struct iproc_asiu_div div; + struct iproc_asiu_gate gate; +}; + +struct iproc_asiu { + void __iomem *div_base; + void __iomem *gate_base; + + struct clk_onecell_data clk_data; + struct iproc_asiu_clk *clks; +}; + +#define to_asiu_clk(hw) container_of(hw, struct iproc_asiu_clk, hw) + +static int iproc_asiu_clk_enable(struct clk_hw *hw) +{ + struct iproc_asiu_clk *clk = to_asiu_clk(hw); + struct iproc_asiu *asiu = clk->asiu; + u32 val; + + /* some clocks at the ASIU level are always enabled */ + if (clk->gate.offset == IPROC_CLK_INVALID_OFFSET) + return 0; + + val = readl(asiu->gate_base + clk->gate.offset); + val |= (1 << clk->gate.en_shift); + writel(val, asiu->gate_base + clk->gate.offset); + + return 0; +} + +static void iproc_asiu_clk_disable(struct clk_hw *hw) +{ + struct iproc_asiu_clk *clk = to_asiu_clk(hw); + struct iproc_asiu *asiu = clk->asiu; + u32 val; + + /* some clocks at the ASIU level are always enabled */ + if (clk->gate.offset == IPROC_CLK_INVALID_OFFSET) + return; + + val = readl(asiu->gate_base + clk->gate.offset); + val &= ~(1 << clk->gate.en_shift); + writel(val, asiu->gate_base + clk->gate.offset); +} + +static unsigned long iproc_asiu_clk_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct iproc_asiu_clk *clk = to_asiu_clk(hw); + struct iproc_asiu *asiu = clk->asiu; + u32 val; + unsigned int div_h, div_l; + + if (parent_rate == 0) { + clk->rate = 0; + return 0; + } + + /* if clock divisor is not enabled, simply return parent rate */ + val = readl(asiu->div_base + clk->div.offset); + if ((val & (1 << clk->div.en_shift)) == 0) { + clk->rate = parent_rate; + return parent_rate; + } + + /* clock rate = parent rate / (high_div + 1) + (low_div + 1) */ + div_h = (val >> clk->div.high_shift) & bit_mask(clk->div.high_width); + div_h++; + div_l = (val >> clk->div.low_shift) & bit_mask(clk->div.low_width); + div_l++; + + clk->rate = parent_rate / (div_h + div_l); + pr_debug("%s: rate: %lu. parent rate: %lu div_h: %u div_l: %u\n", + __func__, clk->rate, parent_rate, div_h, div_l); + + return clk->rate; +} + +static long iproc_asiu_clk_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + unsigned int div; + + if (rate == 0 || *parent_rate == 0) + return -EINVAL; + + if (rate == *parent_rate) + return *parent_rate; + + div = DIV_ROUND_UP(*parent_rate, rate); + if (div < 2) + return *parent_rate; + + return *parent_rate / div; +} + +static int iproc_asiu_clk_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct iproc_asiu_clk *clk = to_asiu_clk(hw); + struct iproc_asiu *asiu = clk->asiu; + unsigned int div, div_h, div_l; + u32 val; + + if (rate == 0 || parent_rate == 0) + return -EINVAL; + + /* simply disable the divisor if one wants the same rate as parent */ + if (rate == parent_rate) { + val = readl(asiu->div_base + clk->div.offset); + val &= ~(1 << clk->div.en_shift); + writel(val, asiu->div_base + clk->div.offset); + return 0; + } + + div = DIV_ROUND_UP(parent_rate, rate); + if (div < 2) + return -EINVAL; + + div_h = div_l = div >> 1; + div_h--; + div_l--; + + val = readl(asiu->div_base + clk->div.offset); + val |= 1 << clk->div.en_shift; + if (div_h) { + val &= ~(bit_mask(clk->div.high_width) + << clk->div.high_shift); + val |= div_h << clk->div.high_shift; + } else { + val &= ~(bit_mask(clk->div.high_width) + << clk->div.high_shift); + } + if (div_l) { + val &= ~(bit_mask(clk->div.low_width) << clk->div.low_shift); + val |= div_l << clk->div.low_shift; + } else { + val &= ~(bit_mask(clk->div.low_width) << clk->div.low_shift); + } + writel(val, asiu->div_base + clk->div.offset); + + return 0; +} + +static const struct clk_ops iproc_asiu_ops = { + .enable = iproc_asiu_clk_enable, + .disable = iproc_asiu_clk_disable, + .recalc_rate = iproc_asiu_clk_recalc_rate, + .round_rate = iproc_asiu_clk_round_rate, + .set_rate = iproc_asiu_clk_set_rate, +}; + +void __init iproc_asiu_setup(struct device_node *node, + const struct iproc_asiu_div *div, + const struct iproc_asiu_gate *gate, + unsigned int num_clks) +{ + int i, ret; + struct iproc_asiu *asiu; + + if (WARN_ON(!gate || !div)) + return; + + asiu = kzalloc(sizeof(*asiu), GFP_KERNEL); + if (WARN_ON(!asiu)) + return; + + asiu->clk_data.clk_num = num_clks; + asiu->clk_data.clks = kcalloc(num_clks, sizeof(*asiu->clk_data.clks), + GFP_KERNEL); + if (WARN_ON(!asiu->clk_data.clks)) + goto err_clks; + + asiu->clks = kcalloc(num_clks, sizeof(*asiu->clks), GFP_KERNEL); + if (WARN_ON(!asiu->clks)) + goto err_asiu_clks; + + asiu->div_base = of_iomap(node, 0); + if (WARN_ON(!asiu->div_base)) + goto err_iomap_div; + + asiu->gate_base = of_iomap(node, 1); + if (WARN_ON(!asiu->gate_base)) + goto err_iomap_gate; + + for (i = 0; i < num_clks; i++) { + struct clk_init_data init; + struct clk *clk; + const char *parent_name; + struct iproc_asiu_clk *asiu_clk; + const char *clk_name; + + ret = of_property_read_string_index(node, "clock-output-names", + i, &clk_name); + if (WARN_ON(ret)) + goto err_clk_register; + + asiu_clk = &asiu->clks[i]; + asiu_clk->name = clk_name; + asiu_clk->asiu = asiu; + asiu_clk->div = div[i]; + asiu_clk->gate = gate[i]; + init.name = clk_name; + init.ops = &iproc_asiu_ops; + init.flags = 0; + parent_name = of_clk_get_parent_name(node, 0); + init.parent_names = (parent_name ? &parent_name : NULL); + init.num_parents = (parent_name ? 1 : 0); + asiu_clk->hw.init = &init; + + clk = clk_register(NULL, &asiu_clk->hw); + if (WARN_ON(IS_ERR(clk))) + goto err_clk_register; + asiu->clk_data.clks[i] = clk; + } + + ret = of_clk_add_provider(node, of_clk_src_onecell_get, + &asiu->clk_data); + if (WARN_ON(ret)) + goto err_clk_register; + + return; + +err_clk_register: + for (i = 0; i < num_clks; i++) + clk_unregister(asiu->clk_data.clks[i]); + iounmap(asiu->gate_base); + +err_iomap_gate: + iounmap(asiu->div_base); + +err_iomap_div: + kfree(asiu->clks); + +err_asiu_clks: + kfree(asiu->clk_data.clks); + +err_clks: + kfree(asiu); +} -- cgit v1.2.3-54-g00ecf