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-rw-r--r--drivers/clk/at91/sckc.c633
1 files changed, 633 insertions, 0 deletions
diff --git a/drivers/clk/at91/sckc.c b/drivers/clk/at91/sckc.c
new file mode 100644
index 000000000..fdc9b669f
--- /dev/null
+++ b/drivers/clk/at91/sckc.c
@@ -0,0 +1,633 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * drivers/clk/at91/sckc.c
+ *
+ * Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/delay.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/io.h>
+
+#define SLOW_CLOCK_FREQ 32768
+#define SLOWCK_SW_CYCLES 5
+#define SLOWCK_SW_TIME_USEC ((SLOWCK_SW_CYCLES * USEC_PER_SEC) / \
+ SLOW_CLOCK_FREQ)
+
+#define AT91_SCKC_CR 0x00
+
+struct clk_slow_bits {
+ u32 cr_rcen;
+ u32 cr_osc32en;
+ u32 cr_osc32byp;
+ u32 cr_oscsel;
+};
+
+struct clk_slow_osc {
+ struct clk_hw hw;
+ void __iomem *sckcr;
+ const struct clk_slow_bits *bits;
+ unsigned long startup_usec;
+};
+
+#define to_clk_slow_osc(hw) container_of(hw, struct clk_slow_osc, hw)
+
+struct clk_sama5d4_slow_osc {
+ struct clk_hw hw;
+ void __iomem *sckcr;
+ const struct clk_slow_bits *bits;
+ unsigned long startup_usec;
+ bool prepared;
+};
+
+#define to_clk_sama5d4_slow_osc(hw) container_of(hw, struct clk_sama5d4_slow_osc, hw)
+
+struct clk_slow_rc_osc {
+ struct clk_hw hw;
+ void __iomem *sckcr;
+ const struct clk_slow_bits *bits;
+ unsigned long frequency;
+ unsigned long accuracy;
+ unsigned long startup_usec;
+};
+
+#define to_clk_slow_rc_osc(hw) container_of(hw, struct clk_slow_rc_osc, hw)
+
+struct clk_sam9x5_slow {
+ struct clk_hw hw;
+ void __iomem *sckcr;
+ const struct clk_slow_bits *bits;
+ u8 parent;
+};
+
+#define to_clk_sam9x5_slow(hw) container_of(hw, struct clk_sam9x5_slow, hw)
+
+static int clk_slow_osc_prepare(struct clk_hw *hw)
+{
+ struct clk_slow_osc *osc = to_clk_slow_osc(hw);
+ void __iomem *sckcr = osc->sckcr;
+ u32 tmp = readl(sckcr);
+
+ if (tmp & (osc->bits->cr_osc32byp | osc->bits->cr_osc32en))
+ return 0;
+
+ writel(tmp | osc->bits->cr_osc32en, sckcr);
+
+ if (system_state < SYSTEM_RUNNING)
+ udelay(osc->startup_usec);
+ else
+ usleep_range(osc->startup_usec, osc->startup_usec + 1);
+
+ return 0;
+}
+
+static void clk_slow_osc_unprepare(struct clk_hw *hw)
+{
+ struct clk_slow_osc *osc = to_clk_slow_osc(hw);
+ void __iomem *sckcr = osc->sckcr;
+ u32 tmp = readl(sckcr);
+
+ if (tmp & osc->bits->cr_osc32byp)
+ return;
+
+ writel(tmp & ~osc->bits->cr_osc32en, sckcr);
+}
+
+static int clk_slow_osc_is_prepared(struct clk_hw *hw)
+{
+ struct clk_slow_osc *osc = to_clk_slow_osc(hw);
+ void __iomem *sckcr = osc->sckcr;
+ u32 tmp = readl(sckcr);
+
+ if (tmp & osc->bits->cr_osc32byp)
+ return 1;
+
+ return !!(tmp & osc->bits->cr_osc32en);
+}
+
+static const struct clk_ops slow_osc_ops = {
+ .prepare = clk_slow_osc_prepare,
+ .unprepare = clk_slow_osc_unprepare,
+ .is_prepared = clk_slow_osc_is_prepared,
+};
+
+static struct clk_hw * __init
+at91_clk_register_slow_osc(void __iomem *sckcr,
+ const char *name,
+ const char *parent_name,
+ unsigned long startup,
+ bool bypass,
+ const struct clk_slow_bits *bits)
+{
+ struct clk_slow_osc *osc;
+ struct clk_hw *hw;
+ struct clk_init_data init;
+ int ret;
+
+ if (!sckcr || !name || !parent_name)
+ return ERR_PTR(-EINVAL);
+
+ osc = kzalloc(sizeof(*osc), GFP_KERNEL);
+ if (!osc)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &slow_osc_ops;
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
+ init.flags = CLK_IGNORE_UNUSED;
+
+ osc->hw.init = &init;
+ osc->sckcr = sckcr;
+ osc->startup_usec = startup;
+ osc->bits = bits;
+
+ if (bypass)
+ writel((readl(sckcr) & ~osc->bits->cr_osc32en) |
+ osc->bits->cr_osc32byp, sckcr);
+
+ hw = &osc->hw;
+ ret = clk_hw_register(NULL, &osc->hw);
+ if (ret) {
+ kfree(osc);
+ hw = ERR_PTR(ret);
+ }
+
+ return hw;
+}
+
+static void at91_clk_unregister_slow_osc(struct clk_hw *hw)
+{
+ struct clk_slow_osc *osc = to_clk_slow_osc(hw);
+
+ clk_hw_unregister(hw);
+ kfree(osc);
+}
+
+static unsigned long clk_slow_rc_osc_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_slow_rc_osc *osc = to_clk_slow_rc_osc(hw);
+
+ return osc->frequency;
+}
+
+static unsigned long clk_slow_rc_osc_recalc_accuracy(struct clk_hw *hw,
+ unsigned long parent_acc)
+{
+ struct clk_slow_rc_osc *osc = to_clk_slow_rc_osc(hw);
+
+ return osc->accuracy;
+}
+
+static int clk_slow_rc_osc_prepare(struct clk_hw *hw)
+{
+ struct clk_slow_rc_osc *osc = to_clk_slow_rc_osc(hw);
+ void __iomem *sckcr = osc->sckcr;
+
+ writel(readl(sckcr) | osc->bits->cr_rcen, sckcr);
+
+ if (system_state < SYSTEM_RUNNING)
+ udelay(osc->startup_usec);
+ else
+ usleep_range(osc->startup_usec, osc->startup_usec + 1);
+
+ return 0;
+}
+
+static void clk_slow_rc_osc_unprepare(struct clk_hw *hw)
+{
+ struct clk_slow_rc_osc *osc = to_clk_slow_rc_osc(hw);
+ void __iomem *sckcr = osc->sckcr;
+
+ writel(readl(sckcr) & ~osc->bits->cr_rcen, sckcr);
+}
+
+static int clk_slow_rc_osc_is_prepared(struct clk_hw *hw)
+{
+ struct clk_slow_rc_osc *osc = to_clk_slow_rc_osc(hw);
+
+ return !!(readl(osc->sckcr) & osc->bits->cr_rcen);
+}
+
+static const struct clk_ops slow_rc_osc_ops = {
+ .prepare = clk_slow_rc_osc_prepare,
+ .unprepare = clk_slow_rc_osc_unprepare,
+ .is_prepared = clk_slow_rc_osc_is_prepared,
+ .recalc_rate = clk_slow_rc_osc_recalc_rate,
+ .recalc_accuracy = clk_slow_rc_osc_recalc_accuracy,
+};
+
+static struct clk_hw * __init
+at91_clk_register_slow_rc_osc(void __iomem *sckcr,
+ const char *name,
+ unsigned long frequency,
+ unsigned long accuracy,
+ unsigned long startup,
+ const struct clk_slow_bits *bits)
+{
+ struct clk_slow_rc_osc *osc;
+ struct clk_hw *hw;
+ struct clk_init_data init;
+ int ret;
+
+ if (!sckcr || !name)
+ return ERR_PTR(-EINVAL);
+
+ osc = kzalloc(sizeof(*osc), GFP_KERNEL);
+ if (!osc)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &slow_rc_osc_ops;
+ init.parent_names = NULL;
+ init.num_parents = 0;
+ init.flags = CLK_IGNORE_UNUSED;
+
+ osc->hw.init = &init;
+ osc->sckcr = sckcr;
+ osc->bits = bits;
+ osc->frequency = frequency;
+ osc->accuracy = accuracy;
+ osc->startup_usec = startup;
+
+ hw = &osc->hw;
+ ret = clk_hw_register(NULL, &osc->hw);
+ if (ret) {
+ kfree(osc);
+ hw = ERR_PTR(ret);
+ }
+
+ return hw;
+}
+
+static void at91_clk_unregister_slow_rc_osc(struct clk_hw *hw)
+{
+ struct clk_slow_rc_osc *osc = to_clk_slow_rc_osc(hw);
+
+ clk_hw_unregister(hw);
+ kfree(osc);
+}
+
+static int clk_sam9x5_slow_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct clk_sam9x5_slow *slowck = to_clk_sam9x5_slow(hw);
+ void __iomem *sckcr = slowck->sckcr;
+ u32 tmp;
+
+ if (index > 1)
+ return -EINVAL;
+
+ tmp = readl(sckcr);
+
+ if ((!index && !(tmp & slowck->bits->cr_oscsel)) ||
+ (index && (tmp & slowck->bits->cr_oscsel)))
+ return 0;
+
+ if (index)
+ tmp |= slowck->bits->cr_oscsel;
+ else
+ tmp &= ~slowck->bits->cr_oscsel;
+
+ writel(tmp, sckcr);
+
+ if (system_state < SYSTEM_RUNNING)
+ udelay(SLOWCK_SW_TIME_USEC);
+ else
+ usleep_range(SLOWCK_SW_TIME_USEC, SLOWCK_SW_TIME_USEC + 1);
+
+ return 0;
+}
+
+static u8 clk_sam9x5_slow_get_parent(struct clk_hw *hw)
+{
+ struct clk_sam9x5_slow *slowck = to_clk_sam9x5_slow(hw);
+
+ return !!(readl(slowck->sckcr) & slowck->bits->cr_oscsel);
+}
+
+static const struct clk_ops sam9x5_slow_ops = {
+ .set_parent = clk_sam9x5_slow_set_parent,
+ .get_parent = clk_sam9x5_slow_get_parent,
+};
+
+static struct clk_hw * __init
+at91_clk_register_sam9x5_slow(void __iomem *sckcr,
+ const char *name,
+ const char **parent_names,
+ int num_parents,
+ const struct clk_slow_bits *bits)
+{
+ struct clk_sam9x5_slow *slowck;
+ struct clk_hw *hw;
+ struct clk_init_data init;
+ int ret;
+
+ if (!sckcr || !name || !parent_names || !num_parents)
+ return ERR_PTR(-EINVAL);
+
+ slowck = kzalloc(sizeof(*slowck), GFP_KERNEL);
+ if (!slowck)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &sam9x5_slow_ops;
+ init.parent_names = parent_names;
+ init.num_parents = num_parents;
+ init.flags = 0;
+
+ slowck->hw.init = &init;
+ slowck->sckcr = sckcr;
+ slowck->bits = bits;
+ slowck->parent = !!(readl(sckcr) & slowck->bits->cr_oscsel);
+
+ hw = &slowck->hw;
+ ret = clk_hw_register(NULL, &slowck->hw);
+ if (ret) {
+ kfree(slowck);
+ hw = ERR_PTR(ret);
+ }
+
+ return hw;
+}
+
+static void at91_clk_unregister_sam9x5_slow(struct clk_hw *hw)
+{
+ struct clk_sam9x5_slow *slowck = to_clk_sam9x5_slow(hw);
+
+ clk_hw_unregister(hw);
+ kfree(slowck);
+}
+
+static void __init at91sam9x5_sckc_register(struct device_node *np,
+ unsigned int rc_osc_startup_us,
+ const struct clk_slow_bits *bits)
+{
+ const char *parent_names[2] = { "slow_rc_osc", "slow_osc" };
+ void __iomem *regbase = of_iomap(np, 0);
+ struct device_node *child = NULL;
+ const char *xtal_name;
+ struct clk_hw *slow_rc, *slow_osc, *slowck;
+ bool bypass;
+ int ret;
+
+ if (!regbase)
+ return;
+
+ slow_rc = at91_clk_register_slow_rc_osc(regbase, parent_names[0],
+ 32768, 50000000,
+ rc_osc_startup_us, bits);
+ if (IS_ERR(slow_rc))
+ return;
+
+ xtal_name = of_clk_get_parent_name(np, 0);
+ if (!xtal_name) {
+ /* DT backward compatibility */
+ child = of_get_compatible_child(np, "atmel,at91sam9x5-clk-slow-osc");
+ if (!child)
+ goto unregister_slow_rc;
+
+ xtal_name = of_clk_get_parent_name(child, 0);
+ bypass = of_property_read_bool(child, "atmel,osc-bypass");
+
+ child = of_get_compatible_child(np, "atmel,at91sam9x5-clk-slow");
+ } else {
+ bypass = of_property_read_bool(np, "atmel,osc-bypass");
+ }
+
+ if (!xtal_name)
+ goto unregister_slow_rc;
+
+ slow_osc = at91_clk_register_slow_osc(regbase, parent_names[1],
+ xtal_name, 1200000, bypass, bits);
+ if (IS_ERR(slow_osc))
+ goto unregister_slow_rc;
+
+ slowck = at91_clk_register_sam9x5_slow(regbase, "slowck", parent_names,
+ 2, bits);
+ if (IS_ERR(slowck))
+ goto unregister_slow_osc;
+
+ /* DT backward compatibility */
+ if (child)
+ ret = of_clk_add_hw_provider(child, of_clk_hw_simple_get,
+ slowck);
+ else
+ ret = of_clk_add_hw_provider(np, of_clk_hw_simple_get, slowck);
+
+ if (WARN_ON(ret))
+ goto unregister_slowck;
+
+ return;
+
+unregister_slowck:
+ at91_clk_unregister_sam9x5_slow(slowck);
+unregister_slow_osc:
+ at91_clk_unregister_slow_osc(slow_osc);
+unregister_slow_rc:
+ at91_clk_unregister_slow_rc_osc(slow_rc);
+}
+
+static const struct clk_slow_bits at91sam9x5_bits = {
+ .cr_rcen = BIT(0),
+ .cr_osc32en = BIT(1),
+ .cr_osc32byp = BIT(2),
+ .cr_oscsel = BIT(3),
+};
+
+static void __init of_at91sam9x5_sckc_setup(struct device_node *np)
+{
+ at91sam9x5_sckc_register(np, 75, &at91sam9x5_bits);
+}
+CLK_OF_DECLARE(at91sam9x5_clk_sckc, "atmel,at91sam9x5-sckc",
+ of_at91sam9x5_sckc_setup);
+
+static void __init of_sama5d3_sckc_setup(struct device_node *np)
+{
+ at91sam9x5_sckc_register(np, 500, &at91sam9x5_bits);
+}
+CLK_OF_DECLARE(sama5d3_clk_sckc, "atmel,sama5d3-sckc",
+ of_sama5d3_sckc_setup);
+
+static const struct clk_slow_bits at91sam9x60_bits = {
+ .cr_osc32en = BIT(1),
+ .cr_osc32byp = BIT(2),
+ .cr_oscsel = BIT(24),
+};
+
+static void __init of_sam9x60_sckc_setup(struct device_node *np)
+{
+ void __iomem *regbase = of_iomap(np, 0);
+ struct clk_hw_onecell_data *clk_data;
+ struct clk_hw *slow_rc, *slow_osc;
+ const char *xtal_name;
+ const char *parent_names[2] = { "slow_rc_osc", "slow_osc" };
+ bool bypass;
+ int ret;
+
+ if (!regbase)
+ return;
+
+ slow_rc = clk_hw_register_fixed_rate_with_accuracy(NULL, parent_names[0],
+ NULL, 0, 32768,
+ 93750000);
+ if (IS_ERR(slow_rc))
+ return;
+
+ xtal_name = of_clk_get_parent_name(np, 0);
+ if (!xtal_name)
+ goto unregister_slow_rc;
+
+ bypass = of_property_read_bool(np, "atmel,osc-bypass");
+ slow_osc = at91_clk_register_slow_osc(regbase, parent_names[1],
+ xtal_name, 5000000, bypass,
+ &at91sam9x60_bits);
+ if (IS_ERR(slow_osc))
+ goto unregister_slow_rc;
+
+ clk_data = kzalloc(struct_size(clk_data, hws, 2), GFP_KERNEL);
+ if (!clk_data)
+ goto unregister_slow_osc;
+
+ /* MD_SLCK and TD_SLCK. */
+ clk_data->num = 2;
+ clk_data->hws[0] = clk_hw_register_fixed_rate(NULL, "md_slck",
+ parent_names[0],
+ 0, 32768);
+ if (IS_ERR(clk_data->hws[0]))
+ goto clk_data_free;
+
+ clk_data->hws[1] = at91_clk_register_sam9x5_slow(regbase, "td_slck",
+ parent_names, 2,
+ &at91sam9x60_bits);
+ if (IS_ERR(clk_data->hws[1]))
+ goto unregister_md_slck;
+
+ ret = of_clk_add_hw_provider(np, of_clk_hw_onecell_get, clk_data);
+ if (WARN_ON(ret))
+ goto unregister_td_slck;
+
+ return;
+
+unregister_td_slck:
+ at91_clk_unregister_sam9x5_slow(clk_data->hws[1]);
+unregister_md_slck:
+ clk_hw_unregister(clk_data->hws[0]);
+clk_data_free:
+ kfree(clk_data);
+unregister_slow_osc:
+ at91_clk_unregister_slow_osc(slow_osc);
+unregister_slow_rc:
+ clk_hw_unregister(slow_rc);
+}
+CLK_OF_DECLARE(sam9x60_clk_sckc, "microchip,sam9x60-sckc",
+ of_sam9x60_sckc_setup);
+
+static int clk_sama5d4_slow_osc_prepare(struct clk_hw *hw)
+{
+ struct clk_sama5d4_slow_osc *osc = to_clk_sama5d4_slow_osc(hw);
+
+ if (osc->prepared)
+ return 0;
+
+ /*
+ * Assume that if it has already been selected (for example by the
+ * bootloader), enough time has already passed.
+ */
+ if ((readl(osc->sckcr) & osc->bits->cr_oscsel)) {
+ osc->prepared = true;
+ return 0;
+ }
+
+ if (system_state < SYSTEM_RUNNING)
+ udelay(osc->startup_usec);
+ else
+ usleep_range(osc->startup_usec, osc->startup_usec + 1);
+ osc->prepared = true;
+
+ return 0;
+}
+
+static int clk_sama5d4_slow_osc_is_prepared(struct clk_hw *hw)
+{
+ struct clk_sama5d4_slow_osc *osc = to_clk_sama5d4_slow_osc(hw);
+
+ return osc->prepared;
+}
+
+static const struct clk_ops sama5d4_slow_osc_ops = {
+ .prepare = clk_sama5d4_slow_osc_prepare,
+ .is_prepared = clk_sama5d4_slow_osc_is_prepared,
+};
+
+static const struct clk_slow_bits at91sama5d4_bits = {
+ .cr_oscsel = BIT(3),
+};
+
+static void __init of_sama5d4_sckc_setup(struct device_node *np)
+{
+ void __iomem *regbase = of_iomap(np, 0);
+ struct clk_hw *slow_rc, *slowck;
+ struct clk_sama5d4_slow_osc *osc;
+ struct clk_init_data init;
+ const char *xtal_name;
+ const char *parent_names[2] = { "slow_rc_osc", "slow_osc" };
+ int ret;
+
+ if (!regbase)
+ return;
+
+ slow_rc = clk_hw_register_fixed_rate_with_accuracy(NULL,
+ parent_names[0],
+ NULL, 0, 32768,
+ 250000000);
+ if (IS_ERR(slow_rc))
+ return;
+
+ xtal_name = of_clk_get_parent_name(np, 0);
+
+ osc = kzalloc(sizeof(*osc), GFP_KERNEL);
+ if (!osc)
+ goto unregister_slow_rc;
+
+ init.name = parent_names[1];
+ init.ops = &sama5d4_slow_osc_ops;
+ init.parent_names = &xtal_name;
+ init.num_parents = 1;
+ init.flags = CLK_IGNORE_UNUSED;
+
+ osc->hw.init = &init;
+ osc->sckcr = regbase;
+ osc->startup_usec = 1200000;
+ osc->bits = &at91sama5d4_bits;
+
+ ret = clk_hw_register(NULL, &osc->hw);
+ if (ret)
+ goto free_slow_osc_data;
+
+ slowck = at91_clk_register_sam9x5_slow(regbase, "slowck",
+ parent_names, 2,
+ &at91sama5d4_bits);
+ if (IS_ERR(slowck))
+ goto unregister_slow_osc;
+
+ ret = of_clk_add_hw_provider(np, of_clk_hw_simple_get, slowck);
+ if (WARN_ON(ret))
+ goto unregister_slowck;
+
+ return;
+
+unregister_slowck:
+ at91_clk_unregister_sam9x5_slow(slowck);
+unregister_slow_osc:
+ clk_hw_unregister(&osc->hw);
+free_slow_osc_data:
+ kfree(osc);
+unregister_slow_rc:
+ clk_hw_unregister(slow_rc);
+}
+CLK_OF_DECLARE(sama5d4_clk_sckc, "atmel,sama5d4-sckc",
+ of_sama5d4_sckc_setup);