diff options
Diffstat (limited to 'drivers/clk/tegra/clk-divider.c')
| -rw-r--r-- | drivers/clk/tegra/clk-divider.c | 107 |
1 files changed, 57 insertions, 50 deletions
diff --git a/drivers/clk/tegra/clk-divider.c b/drivers/clk/tegra/clk-divider.c index 4d75b1f37e3a..37439fcb3ac0 100644 --- a/drivers/clk/tegra/clk-divider.c +++ b/drivers/clk/tegra/clk-divider.c @@ -1,17 +1,6 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved. - * - * This program is free software; you can redistribute it and/or modify it - * under the terms and conditions of the GNU General Public License, - * version 2, as published by the Free Software Foundation. - * - * This program is distributed in the hope 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, see <http://www.gnu.org/licenses/>. */ #include <linux/kernel.h> @@ -19,7 +8,6 @@ #include <linux/err.h> #include <linux/slab.h> #include <linux/clk-provider.h> -#include <linux/clk.h> #include "clk.h" @@ -33,35 +21,15 @@ static int get_div(struct tegra_clk_frac_div *divider, unsigned long rate, unsigned long parent_rate) { - s64 divider_ux1 = parent_rate; - u8 flags = divider->flags; - int mul; - - if (!rate) - return 0; - - mul = get_mul(divider); - - if (!(flags & TEGRA_DIVIDER_INT)) - divider_ux1 *= mul; - - if (flags & TEGRA_DIVIDER_ROUND_UP) - divider_ux1 += rate - 1; - - do_div(divider_ux1, rate); - - if (flags & TEGRA_DIVIDER_INT) - divider_ux1 *= mul; + int div; - divider_ux1 -= mul; + div = div_frac_get(rate, parent_rate, divider->width, + divider->frac_width, divider->flags); - if (divider_ux1 < 0) + if (div < 0) return 0; - if (divider_ux1 > get_max_div(divider)) - return -EINVAL; - - return divider_ux1; + return div; } static unsigned long clk_frac_div_recalc_rate(struct clk_hw *hw, @@ -72,8 +40,13 @@ static unsigned long clk_frac_div_recalc_rate(struct clk_hw *hw, int div, mul; u64 rate = parent_rate; - reg = readl_relaxed(divider->reg) >> divider->shift; - div = reg & div_mask(divider); + reg = readl_relaxed(divider->reg); + + if ((divider->flags & TEGRA_DIVIDER_UART) && + !(reg & PERIPH_CLK_UART_DIV_ENB)) + return rate; + + div = (reg >> divider->shift) & div_mask(divider); mul = get_mul(divider); div += mul; @@ -85,23 +58,31 @@ static unsigned long clk_frac_div_recalc_rate(struct clk_hw *hw, return rate; } -static long clk_frac_div_round_rate(struct clk_hw *hw, unsigned long rate, - unsigned long *prate) +static int clk_frac_div_determine_rate(struct clk_hw *hw, + struct clk_rate_request *req) { struct tegra_clk_frac_div *divider = to_clk_frac_div(hw); int div, mul; - unsigned long output_rate = *prate; + unsigned long output_rate = req->best_parent_rate; - if (!rate) - return output_rate; + if (!req->rate) { + req->rate = output_rate; - div = get_div(divider, rate, output_rate); - if (div < 0) - return *prate; + return 0; + } + + div = get_div(divider, req->rate, output_rate); + if (div < 0) { + req->rate = req->best_parent_rate; + + return 0; + } mul = get_mul(divider); - return DIV_ROUND_UP(output_rate * mul, div + mul); + req->rate = DIV_ROUND_UP(output_rate * mul, div + mul); + + return 0; } static int clk_frac_div_set_rate(struct clk_hw *hw, unsigned long rate, @@ -141,10 +122,21 @@ static int clk_frac_div_set_rate(struct clk_hw *hw, unsigned long rate, return 0; } +static void clk_divider_restore_context(struct clk_hw *hw) +{ + struct clk_hw *parent = clk_hw_get_parent(hw); + unsigned long parent_rate = clk_hw_get_rate(parent); + unsigned long rate = clk_hw_get_rate(hw); + + if (clk_frac_div_set_rate(hw, rate, parent_rate) < 0) + WARN_ON(1); +} + const struct clk_ops tegra_clk_frac_div_ops = { .recalc_rate = clk_frac_div_recalc_rate, .set_rate = clk_frac_div_set_rate, - .round_rate = clk_frac_div_round_rate, + .determine_rate = clk_frac_div_determine_rate, + .restore_context = clk_divider_restore_context, }; struct clk *tegra_clk_register_divider(const char *name, @@ -185,3 +177,18 @@ struct clk *tegra_clk_register_divider(const char *name, return clk; } + +static const struct clk_div_table mc_div_table[] = { + { .val = 0, .div = 2 }, + { .val = 1, .div = 1 }, + { .val = 0, .div = 0 }, +}; + +struct clk *tegra_clk_register_mc(const char *name, const char *parent_name, + void __iomem *reg, spinlock_t *lock) +{ + return clk_register_divider_table(NULL, name, parent_name, + CLK_IS_CRITICAL, + reg, 16, 1, CLK_DIVIDER_READ_ONLY, + mc_div_table, lock); +} |