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path: root/drivers/clk/tegra/clk-sdmmc-mux.c
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-rw-r--r--drivers/clk/tegra/clk-sdmmc-mux.c278
1 files changed, 278 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 000000000..4f2c3309e
--- /dev/null
+++ b/drivers/clk/tegra/clk-sdmmc-mux.c
@@ -0,0 +1,278 @@
+// 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/io.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 void clk_sdmmc_mux_disable_unused(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_unused(gate_hw);
+}
+
+static void clk_sdmmc_mux_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);
+ int parent_id;
+
+ parent_id = clk_hw_get_parent_index(hw);
+ if (WARN_ON(parent_id < 0))
+ return;
+
+ clk_sdmmc_mux_set_parent(hw, parent_id);
+ clk_sdmmc_mux_set_rate(hw, rate, parent_rate);
+}
+
+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,
+ .disable_unused = clk_sdmmc_mux_disable_unused,
+ .restore_context = clk_sdmmc_mux_restore_context,
+};
+
+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;
+}