[PATCH v5 3/3] clk: meson: add sub MMC clock controller driver

Jianxin Pan
2018-10-18T05:07:25Z

From: Yixun Lan <yixun.lan@amlogic.com>

The patch will add a MMC clock controller driver which used by MMC or NAND,
It provide a mux and divider clock, and three phase clocks - core, tx, tx.

Two clocks are provided as the parent of MMC clock controller from
upper layer clock controller - eg "amlogic,axg-clkc" in AXG platform.

To specify which clock the MMC or NAND driver may consume,
the preprocessor macros in the dt-bindings/clock/amlogic,mmc-clkc.h header
can be used in the device tree sources.

Signed-off-by: Yixun Lan <yixun.lan@amlogic.com>
Signed-off-by: Jianxin Pan <jianxin.pan@amlogic.com>
---
drivers/clk/meson/Kconfig | 10 ++
drivers/clk/meson/Makefile | 1 +
drivers/clk/meson/clk-regmap.c | 27 +++-
drivers/clk/meson/clk-regmap.h | 1 +
drivers/clk/meson/mmc-clkc.c | 296 +++++++++++++++++++++++++++++++++++++++++
5 files changed, 334 insertions(+), 1 deletion(-)
create mode 100644 drivers/clk/meson/mmc-clkc.c

diff --git a/drivers/clk/meson/Kconfig b/drivers/clk/meson/Kconfig
index efaa70f..8b8ccbc 100644
--- a/drivers/clk/meson/Kconfig
+++ b/drivers/clk/meson/Kconfig
@@ -15,6 +15,16 @@ config COMMON_CLK_MESON_AO
select COMMON_CLK_REGMAP_MESON
select RESET_CONTROLLER

+config COMMON_CLK_MMC_MESON
+ tristate "Meson MMC Sub Clock Controller Driver"
+ depends on COMMON_CLK_AMLOGIC
+ select MFD_SYSCON
+ select REGMAP
+ help
+ Support for the MMC sub clock controller on Amlogic Meson Platform,
+ which include S905 (GXBB, GXL), A113D/X (AXG) devices.
+ Say Y if you want this clock enabled.
+
config COMMON_CLK_REGMAP_MESON
bool
select REGMAP
diff --git a/drivers/clk/meson/Makefile b/drivers/clk/meson/Makefile
index 39ce566..31c16d5 100644
--- a/drivers/clk/meson/Makefile
+++ b/drivers/clk/meson/Makefile
@@ -9,4 +9,5 @@ obj-$(CONFIG_COMMON_CLK_MESON8B) += meson8b.o
obj-$(CONFIG_COMMON_CLK_GXBB) += gxbb.o gxbb-aoclk.o gxbb-aoclk-32k.o
obj-$(CONFIG_COMMON_CLK_AXG) += axg.o axg-aoclk.o
obj-$(CONFIG_COMMON_CLK_AXG_AUDIO) += axg-audio.o
+obj-$(CONFIG_COMMON_CLK_MMC_MESON) += mmc-clkc.o
obj-$(CONFIG_COMMON_CLK_REGMAP_MESON) += clk-regmap.o
diff --git a/drivers/clk/meson/clk-regmap.c b/drivers/clk/meson/clk-regmap.c
index 305ee30..f96314d 100644
--- a/drivers/clk/meson/clk-regmap.c
+++ b/drivers/clk/meson/clk-regmap.c
@@ -113,8 +113,25 @@ static int clk_regmap_div_set_rate(struct clk_hw *hw, unsigned long rate,
clk_div_mask(div->width) << div->shift, val);
};

-/* Would prefer clk_regmap_div_ro_ops but clashes with qcom */
+static void clk_regmap_div_init(struct clk_hw *hw)
+{
+ struct clk_regmap *clk = to_clk_regmap(hw);
+ struct clk_regmap_div_data *div = clk_get_regmap_div_data(clk);
+ unsigned int val;
+ int ret;
+
+ ret = regmap_read(clk->map, div->offset, &val);
+ if (ret)
+ return;

+ val &= (clk_div_mask(div->width) << div->shift);
+ if (!val)
+ regmap_update_bits(clk->map, div->offset,
+ clk_div_mask(div->width) << div->shift,
+ clk_div_mask(div->width));
+}
+
+/* Would prefer clk_regmap_div_ro_ops but clashes with qcom */
const struct clk_ops clk_regmap_divider_ops = {
.recalc_rate = clk_regmap_div_recalc_rate,
.round_rate = clk_regmap_div_round_rate,
@@ -122,6 +139,14 @@ static int clk_regmap_div_set_rate(struct clk_hw *hw, unsigned long rate,
};
EXPORT_SYMBOL_GPL(clk_regmap_divider_ops);

+const struct clk_ops clk_regmap_divider_with_init_ops = {
+ .recalc_rate = clk_regmap_div_recalc_rate,
+ .round_rate = clk_regmap_div_round_rate,
+ .set_rate = clk_regmap_div_set_rate,
+ .init = clk_regmap_div_init,
+};
+EXPORT_SYMBOL_GPL(clk_regmap_divider_with_init_ops);
+
const struct clk_ops clk_regmap_divider_ro_ops = {
.recalc_rate = clk_regmap_div_recalc_rate,
.round_rate = clk_regmap_div_round_rate,
diff --git a/drivers/clk/meson/clk-regmap.h b/drivers/clk/meson/clk-regmap.h
index ed2d434..0ab7d37 100644
--- a/drivers/clk/meson/clk-regmap.h
+++ b/drivers/clk/meson/clk-regmap.h
@@ -109,5 +109,6 @@ struct clk_regmap_mux_data {

extern const struct clk_ops clk_regmap_mux_ops;
extern const struct clk_ops clk_regmap_mux_ro_ops;
+extern const struct clk_ops clk_regmap_divider_with_init_ops;

#endif /* __CLK_REGMAP_H */
diff --git a/drivers/clk/meson/mmc-clkc.c b/drivers/clk/meson/mmc-clkc.c
new file mode 100644
index 0000000..5555e3f
--- /dev/null
+++ b/drivers/clk/meson/mmc-clkc.c
@@ -0,0 +1,296 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+/*
+ * Amlogic Meson MMC Sub Clock Controller Driver
+ *
+ * Copyright (c) 2017 Baylibre SAS.
+ * Author: Jerome Brunet <jbrunet@baylibre.com>
+ *
+ * Copyright (c) 2018 Amlogic, inc.
+ * Author: Yixun Lan <yixun.lan@amlogic.com>
+ */
+
+#include <linux/clk.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+#include <linux/of_device.h>
+#include <linux/mfd/syscon.h>
+#include <linux/platform_device.h>
+#include <dt-bindings/clock/amlogic,mmc-clkc.h>
+
+#include "clkc.h"
+
+/* clock ID used by internal driver */
+#define CLKID_MMC_MUX 0
+
+#define SD_EMMC_CLOCK 0
+#define CLK_DELAY_STEP_PS 200
+#define CLK_PHASE_STEP 30
+#define CLK_PHASE_POINT_NUM (360 / CLK_PHASE_STEP)
+
+#define MUX_CLK_NUM_PARENTS 2
+#define MMC_MAX_CLKS 5
+
+struct mmc_clkc_data {
+ struct meson_clk_phase_delay_data tx;
+ struct meson_clk_phase_delay_data rx;
+};
+
+static struct clk_regmap_mux_data mmc_clkc_mux_data = {
+ .offset = SD_EMMC_CLOCK,
+ .mask = 0x3,
+ .shift = 6,
+ .flags = CLK_DIVIDER_ROUND_CLOSEST,
+};
+
+static struct clk_regmap_div_data mmc_clkc_div_data = {
+ .offset = SD_EMMC_CLOCK,
+ .shift = 0,
+ .width = 6,
+ .flags = CLK_DIVIDER_ROUND_CLOSEST | CLK_DIVIDER_ONE_BASED,
+};
+
+static struct meson_clk_phase_data mmc_clkc_core_phase = {
+ .ph = {
+ .reg_off = SD_EMMC_CLOCK,
+ .shift = 8,
+ .width = 2,
+ }
+};
+
+static const struct mmc_clkc_data mmc_clkc_gx_data = {
+ .tx = {
+ .phase = {
+ .reg_off = SD_EMMC_CLOCK,
+ .shift = 10,
+ .width = 2,
+ },
+ .delay = {
+ .reg_off = SD_EMMC_CLOCK,
+ .shift = 16,
+ .width = 4,
+ },
+ .delay_step_ps = CLK_DELAY_STEP_PS,
+ },
+ .rx = {
+ .phase = {
+ .reg_off = SD_EMMC_CLOCK,
+ .shift = 12,
+ .width = 2,
+ },
+ .delay = {
+ .reg_off = SD_EMMC_CLOCK,
+ .shift = 20,
+ .width = 4,
+ },
+ .delay_step_ps = CLK_DELAY_STEP_PS,
+ },
+};
+
+static const struct mmc_clkc_data mmc_clkc_axg_data = {
+ .tx = {
+ .phase = {
+ .reg_off = SD_EMMC_CLOCK,
+ .shift = 10,
+ .width = 2,
+ },
+ .delay = {
+ .reg_off = SD_EMMC_CLOCK,
+ .shift = 16,
+ .width = 6,
+ },
+ .delay_step_ps = CLK_DELAY_STEP_PS,
+ },
+ .rx = {
+ .phase = {
+ .reg_off = SD_EMMC_CLOCK,
+ .shift = 12,
+ .width = 2,
+ },
+ .delay = {
+ .reg_off = SD_EMMC_CLOCK,
+ .shift = 22,
+ .width = 6,
+ },
+ .delay_step_ps = CLK_DELAY_STEP_PS,
+ },
+};
+
+static const struct of_device_id mmc_clkc_match_table[] = {
+ {
+ .compatible = "amlogic,gx-mmc-clkc",
+ .data = &mmc_clkc_gx_data
+ },
+ {
+ .compatible = "amlogic,axg-mmc-clkc",
+ .data = &mmc_clkc_axg_data
+ },
+ {}
+};
+MODULE_DEVICE_TABLE(of, mmc_clkc_match_table);
+
+static struct clk_regmap *
+mmc_clkc_register_clk(struct device *dev, struct regmap *map,
+ struct clk_init_data *init,
+ const char *suffix, void *data)
+{
+ struct clk_regmap *clk;
+ char *name;
+ int ret;
+
+ clk = devm_kzalloc(dev, sizeof(*clk), GFP_KERNEL);
+ if (!clk)
+ return ERR_PTR(-ENOMEM);
+
+ name = kasprintf(GFP_KERNEL, "%s#%s", dev_name(dev), suffix);
+ if (!name)
+ return ERR_PTR(-ENOMEM);
+
+ init->name = name;
+
+ clk->map = map;
+ clk->data = data;
+ clk->hw.init = init;
+
+ ret = devm_clk_hw_register(dev, &clk->hw);
+ if (ret)
+ clk = ERR_PTR(ret);
+
+ kfree(name);
+ return clk;
+}
+
+static struct clk_regmap *mmc_clkc_register_mux(struct device *dev,
+ struct regmap *map)
+{
+ const char *parent_names[MUX_CLK_NUM_PARENTS];
+ struct clk_init_data init;
+ struct clk_regmap *mux;
+ struct clk *clk;
+ int i;
+
+ for (i = 0; i < MUX_CLK_NUM_PARENTS; i++) {
+ char name[8];
+
+ snprintf(name, sizeof(name), "clkin%d", i);
+ clk = devm_clk_get(dev, name);
+ if (IS_ERR(clk)) {
+ if (clk != ERR_PTR(-EPROBE_DEFER))
+ dev_err(dev, "Missing clock %s\n", name);
+ return ERR_PTR((long)clk);
+ }
+
+ parent_names[i] = __clk_get_name(clk);
+ }
+
+ init.ops = &clk_regmap_mux_ops;
+ init.flags = CLK_SET_RATE_PARENT;
+ init.parent_names = parent_names;
+ init.num_parents = MUX_CLK_NUM_PARENTS;
+
+ mux = mmc_clkc_register_clk(dev, map, &init, "mux", &mmc_clkc_mux_data);
+ if (IS_ERR(mux))
+ dev_err(dev, "Mux clock registration failed\n");
+
+ return mux;
+}
+
+static struct clk_regmap *
+mmc_clkc_register_clk_with_parent(struct device *dev, struct regmap *map,
+ char *suffix, const char *parent,
+ unsigned long flags,
+ const struct clk_ops *ops, void *data)
+{
+ struct clk_init_data init;
+ struct clk_regmap *clk;
+
+ init.ops = ops;
+ init.flags = flags;
+ init.parent_names = (const char* const []){ parent, };
+ init.num_parents = 1;
+
+ clk = mmc_clkc_register_clk(dev, map, &init, suffix, data);
+ if (IS_ERR(clk))
+ dev_err(dev, "Core %s clock registration failed\n", suffix);
+
+ return clk;
+}
+
+static int mmc_clkc_probe(struct platform_device *pdev)
+{
+ struct clk_hw_onecell_data *onecell_data;
+ struct device *dev = &pdev->dev;
+ struct mmc_clkc_data *data;
+ struct regmap *map;
+ struct clk_regmap *mux, *div, *core, *rx, *tx;
+
+ data = (struct mmc_clkc_data *)of_device_get_match_data(dev);
+ if (!data)
+ return -ENODEV;
+
+ map = syscon_node_to_regmap(dev->of_node);
+ if (IS_ERR(map)) {
+ dev_err(dev, "could not find mmc clock controller\n");
+ return PTR_ERR(map);
+ }
+
+ onecell_data = devm_kzalloc(dev, sizeof(*onecell_data) +
+ sizeof(*onecell_data->hws) * MMC_MAX_CLKS,
+ GFP_KERNEL);
+ if (!onecell_data)
+ return -ENOMEM;
+
+ mux = mmc_clkc_register_mux(dev, map);
+ if (IS_ERR(mux))
+ return PTR_ERR(mux);
+
+ div = mmc_clkc_register_clk_with_parent(dev, map, "div",
+ clk_hw_get_name(&mux->hw),
+ CLK_SET_RATE_PARENT,
+ &clk_regmap_divider_with_init_ops,
+ &mmc_clkc_div_data);
+ if (IS_ERR(div))
+ return PTR_ERR(div);
+
+ core = mmc_clkc_register_clk_with_parent(dev, map, "core",
+ clk_hw_get_name(&div->hw),
+ CLK_SET_RATE_PARENT,
+ &meson_clk_phase_ops,
+ &mmc_clkc_core_phase);
+ if (IS_ERR(core))
+ return PTR_ERR(core);
+
+ rx = mmc_clkc_register_clk_with_parent(dev, map, "rx",
+ clk_hw_get_name(&core->hw), 0,
+ &meson_clk_phase_delay_ops,
+ &data->rx);
+ if (IS_ERR(rx))
+ return PTR_ERR(rx);
+
+ tx = mmc_clkc_register_clk_with_parent(dev, map, "tx",
+ clk_hw_get_name(&core->hw), 0,
+ &meson_clk_phase_delay_ops,
+ &data->tx);
+ if (IS_ERR(tx))
+ return PTR_ERR(tx);
+
+ onecell_data->hws[CLKID_MMC_MUX] = &mux->hw,
+ onecell_data->hws[CLKID_MMC_DIV] = &div->hw,
+ onecell_data->hws[CLKID_MMC_PHASE_CORE] = &core->hw,
+ onecell_data->hws[CLKID_MMC_PHASE_RX] = &rx->hw,
+ onecell_data->hws[CLKID_MMC_PHASE_TX] = &tx->hw,
+ onecell_data->num = MMC_MAX_CLKS;
+
+ return devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get,
+ onecell_data);
+}
+
+static struct platform_driver mmc_clkc_driver = {
+ .probe = mmc_clkc_probe,
+ .driver = {
+ .name = "meson-mmc-clkc",
+ .of_match_table = of_match_ptr(mmc_clkc_match_table),
+ },
+};
+
+module_platform_driver(mmc_clkc_driver);
--
1.9.1