diff options
Diffstat (limited to 'drivers/clk/tegra/clk-sdmmc-mux.c')
| -rw-r--r-- | drivers/clk/tegra/clk-sdmmc-mux.c | 251 |
1 files changed, 251 insertions, 0 deletions
diff --git a/drivers/clk/tegra/clk-sdmmc-mux.c b/drivers/clk/tegra/clk-sdmmc-mux.c new file mode 100644 index 000000000000..473d418533cb --- /dev/null +++ b/drivers/clk/tegra/clk-sdmmc-mux.c @@ -0,0 +1,251 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2018 NVIDIA CORPORATION. All rights reserved. + * + * based on clk-mux.c + * + * Copyright (C) 2011 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de> + * Copyright (C) 2011 Richard Zhao, Linaro <richard.zhao@linaro.org> + * Copyright (C) 2011-2012 Mike Turquette, Linaro Ltd <mturquette@linaro.org> + * + */ + +#include <linux/clk-provider.h> +#include <linux/err.h> +#include <linux/types.h> + +#include "clk.h" + +#define DIV_MASK GENMASK(7, 0) +#define MUX_SHIFT 29 +#define MUX_MASK GENMASK(MUX_SHIFT + 2, MUX_SHIFT) +#define SDMMC_MUL 2 + +#define get_max_div(d) DIV_MASK +#define get_div_field(val) ((val) & DIV_MASK) +#define get_mux_field(val) (((val) & MUX_MASK) >> MUX_SHIFT) + +static const char * const mux_sdmmc_parents[] = { + "pll_p", "pll_c4_out2", "pll_c4_out0", "pll_c4_out1", "clk_m" +}; + +static const u8 mux_lj_idx[] = { + [0] = 0, [1] = 1, [2] = 2, [3] = 5, [4] = 6 +}; + +static const u8 mux_non_lj_idx[] = { + [0] = 0, [1] = 3, [2] = 7, [3] = 4, [4] = 6 +}; + +static u8 clk_sdmmc_mux_get_parent(struct clk_hw *hw) +{ + struct tegra_sdmmc_mux *sdmmc_mux = to_clk_sdmmc_mux(hw); + int num_parents, i; + u32 src, val; + const u8 *mux_idx; + + num_parents = clk_hw_get_num_parents(hw); + + val = readl_relaxed(sdmmc_mux->reg); + src = get_mux_field(val); + if (get_div_field(val)) + mux_idx = mux_non_lj_idx; + else + mux_idx = mux_lj_idx; + + for (i = 0; i < num_parents; i++) { + if (mux_idx[i] == src) + return i; + } + + WARN(1, "Unknown parent selector %d\n", src); + + return 0; +} + +static int clk_sdmmc_mux_set_parent(struct clk_hw *hw, u8 index) +{ + struct tegra_sdmmc_mux *sdmmc_mux = to_clk_sdmmc_mux(hw); + u32 val; + + + val = readl_relaxed(sdmmc_mux->reg); + if (get_div_field(val)) + index = mux_non_lj_idx[index]; + else + index = mux_lj_idx[index]; + + val &= ~MUX_MASK; + val |= index << MUX_SHIFT; + + writel(val, sdmmc_mux->reg); + + return 0; +} + +static unsigned long clk_sdmmc_mux_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct tegra_sdmmc_mux *sdmmc_mux = to_clk_sdmmc_mux(hw); + u32 val; + int div; + u64 rate = parent_rate; + + val = readl_relaxed(sdmmc_mux->reg); + div = get_div_field(val); + + div += SDMMC_MUL; + + rate *= SDMMC_MUL; + rate += div - 1; + do_div(rate, div); + + return rate; +} + +static int clk_sdmmc_mux_determine_rate(struct clk_hw *hw, + struct clk_rate_request *req) +{ + struct tegra_sdmmc_mux *sdmmc_mux = to_clk_sdmmc_mux(hw); + int div; + unsigned long output_rate = req->best_parent_rate; + + req->rate = max(req->rate, req->min_rate); + req->rate = min(req->rate, req->max_rate); + + if (!req->rate) + return output_rate; + + div = div_frac_get(req->rate, output_rate, 8, 1, sdmmc_mux->div_flags); + if (div < 0) + div = 0; + + if (sdmmc_mux->div_flags & TEGRA_DIVIDER_ROUND_UP) + req->rate = DIV_ROUND_UP(output_rate * SDMMC_MUL, + div + SDMMC_MUL); + else + req->rate = output_rate * SDMMC_MUL / (div + SDMMC_MUL); + + return 0; +} + +static int clk_sdmmc_mux_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct tegra_sdmmc_mux *sdmmc_mux = to_clk_sdmmc_mux(hw); + int div; + unsigned long flags = 0; + u32 val; + u8 src; + + div = div_frac_get(rate, parent_rate, 8, 1, sdmmc_mux->div_flags); + if (div < 0) + return div; + + if (sdmmc_mux->lock) + spin_lock_irqsave(sdmmc_mux->lock, flags); + + src = clk_sdmmc_mux_get_parent(hw); + if (div) + src = mux_non_lj_idx[src]; + else + src = mux_lj_idx[src]; + + val = src << MUX_SHIFT; + val |= div; + writel(val, sdmmc_mux->reg); + fence_udelay(2, sdmmc_mux->reg); + + if (sdmmc_mux->lock) + spin_unlock_irqrestore(sdmmc_mux->lock, flags); + + return 0; +} + +static int clk_sdmmc_mux_is_enabled(struct clk_hw *hw) +{ + struct tegra_sdmmc_mux *sdmmc_mux = to_clk_sdmmc_mux(hw); + const struct clk_ops *gate_ops = sdmmc_mux->gate_ops; + struct clk_hw *gate_hw = &sdmmc_mux->gate.hw; + + __clk_hw_set_clk(gate_hw, hw); + + return gate_ops->is_enabled(gate_hw); +} + +static int clk_sdmmc_mux_enable(struct clk_hw *hw) +{ + struct tegra_sdmmc_mux *sdmmc_mux = to_clk_sdmmc_mux(hw); + const struct clk_ops *gate_ops = sdmmc_mux->gate_ops; + struct clk_hw *gate_hw = &sdmmc_mux->gate.hw; + + __clk_hw_set_clk(gate_hw, hw); + + return gate_ops->enable(gate_hw); +} + +static void clk_sdmmc_mux_disable(struct clk_hw *hw) +{ + struct tegra_sdmmc_mux *sdmmc_mux = to_clk_sdmmc_mux(hw); + const struct clk_ops *gate_ops = sdmmc_mux->gate_ops; + struct clk_hw *gate_hw = &sdmmc_mux->gate.hw; + + gate_ops->disable(gate_hw); +} + +static const struct clk_ops tegra_clk_sdmmc_mux_ops = { + .get_parent = clk_sdmmc_mux_get_parent, + .set_parent = clk_sdmmc_mux_set_parent, + .determine_rate = clk_sdmmc_mux_determine_rate, + .recalc_rate = clk_sdmmc_mux_recalc_rate, + .set_rate = clk_sdmmc_mux_set_rate, + .is_enabled = clk_sdmmc_mux_is_enabled, + .enable = clk_sdmmc_mux_enable, + .disable = clk_sdmmc_mux_disable, +}; + +struct clk *tegra_clk_register_sdmmc_mux_div(const char *name, + void __iomem *clk_base, u32 offset, u32 clk_num, u8 div_flags, + unsigned long flags, void *lock) +{ + struct clk *clk; + struct clk_init_data init; + const struct tegra_clk_periph_regs *bank; + struct tegra_sdmmc_mux *sdmmc_mux; + + init.ops = &tegra_clk_sdmmc_mux_ops; + init.name = name; + init.flags = flags; + init.parent_names = mux_sdmmc_parents; + init.num_parents = ARRAY_SIZE(mux_sdmmc_parents); + + bank = get_reg_bank(clk_num); + if (!bank) + return ERR_PTR(-EINVAL); + + sdmmc_mux = kzalloc(sizeof(*sdmmc_mux), GFP_KERNEL); + if (!sdmmc_mux) + return ERR_PTR(-ENOMEM); + + /* Data in .init is copied by clk_register(), so stack variable OK */ + sdmmc_mux->hw.init = &init; + sdmmc_mux->reg = clk_base + offset; + sdmmc_mux->lock = lock; + sdmmc_mux->gate.clk_base = clk_base; + sdmmc_mux->gate.regs = bank; + sdmmc_mux->gate.enable_refcnt = periph_clk_enb_refcnt; + sdmmc_mux->gate.clk_num = clk_num; + sdmmc_mux->gate.flags = TEGRA_PERIPH_ON_APB; + sdmmc_mux->div_flags = div_flags; + sdmmc_mux->gate_ops = &tegra_clk_periph_gate_ops; + + clk = clk_register(NULL, &sdmmc_mux->hw); + if (IS_ERR(clk)) { + kfree(sdmmc_mux); + return clk; + } + + sdmmc_mux->gate.hw.clk = clk; + + return clk; +} |