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path: root/drivers/clk/at91/sckc.c
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-rw-r--r--drivers/clk/at91/sckc.c464
1 files changed, 463 insertions, 1 deletions
diff --git a/drivers/clk/at91/sckc.c b/drivers/clk/at91/sckc.c
index 1184d76a7ab7..ab6ecefc49ad 100644
--- a/drivers/clk/at91/sckc.c
+++ b/drivers/clk/at91/sckc.c
@@ -12,11 +12,382 @@
#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>
-#include "sckc.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
+#define AT91_SCKC_RCEN (1 << 0)
+#define AT91_SCKC_OSC32EN (1 << 1)
+#define AT91_SCKC_OSC32BYP (1 << 2)
+#define AT91_SCKC_OSCSEL (1 << 3)
+
+struct clk_slow_osc {
+ struct clk_hw hw;
+ void __iomem *sckcr;
+ 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;
+ 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;
+ 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;
+ 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 & (AT91_SCKC_OSC32BYP | AT91_SCKC_OSC32EN))
+ return 0;
+
+ writel(tmp | AT91_SCKC_OSC32EN, sckcr);
+
+ 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 & AT91_SCKC_OSC32BYP)
+ return;
+
+ writel(tmp & ~AT91_SCKC_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 & AT91_SCKC_OSC32BYP)
+ return 1;
+
+ return !!(tmp & AT91_SCKC_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)
+{
+ 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;
+
+ if (bypass)
+ writel((readl(sckcr) & ~AT91_SCKC_OSC32EN) | AT91_SCKC_OSC32BYP,
+ sckcr);
+
+ hw = &osc->hw;
+ ret = clk_hw_register(NULL, &osc->hw);
+ if (ret) {
+ kfree(osc);
+ hw = ERR_PTR(ret);
+ }
+
+ return hw;
+}
+
+static void __init
+of_at91sam9x5_clk_slow_osc_setup(struct device_node *np, void __iomem *sckcr)
+{
+ struct clk_hw *hw;
+ const char *parent_name;
+ const char *name = np->name;
+ u32 startup;
+ bool bypass;
+
+ parent_name = of_clk_get_parent_name(np, 0);
+ of_property_read_string(np, "clock-output-names", &name);
+ of_property_read_u32(np, "atmel,startup-time-usec", &startup);
+ bypass = of_property_read_bool(np, "atmel,osc-bypass");
+
+ hw = at91_clk_register_slow_osc(sckcr, name, parent_name, startup,
+ bypass);
+ if (IS_ERR(hw))
+ return;
+
+ of_clk_add_hw_provider(np, of_clk_hw_simple_get, hw);
+}
+
+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) | AT91_SCKC_RCEN, sckcr);
+
+ 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) & ~AT91_SCKC_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) & AT91_SCKC_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)
+{
+ 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->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 __init
+of_at91sam9x5_clk_slow_rc_osc_setup(struct device_node *np, void __iomem *sckcr)
+{
+ struct clk_hw *hw;
+ u32 frequency = 0;
+ u32 accuracy = 0;
+ u32 startup = 0;
+ const char *name = np->name;
+
+ of_property_read_string(np, "clock-output-names", &name);
+ of_property_read_u32(np, "clock-frequency", &frequency);
+ of_property_read_u32(np, "clock-accuracy", &accuracy);
+ of_property_read_u32(np, "atmel,startup-time-usec", &startup);
+
+ hw = at91_clk_register_slow_rc_osc(sckcr, name, frequency, accuracy,
+ startup);
+ if (IS_ERR(hw))
+ return;
+
+ of_clk_add_hw_provider(np, of_clk_hw_simple_get, hw);
+}
+
+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 & AT91_SCKC_OSCSEL)) ||
+ (index && (tmp & AT91_SCKC_OSCSEL)))
+ return 0;
+
+ if (index)
+ tmp |= AT91_SCKC_OSCSEL;
+ else
+ tmp &= ~AT91_SCKC_OSCSEL;
+
+ writel(tmp, sckcr);
+
+ 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) & AT91_SCKC_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)
+{
+ 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->parent = !!(readl(sckcr) & AT91_SCKC_OSCSEL);
+
+ hw = &slowck->hw;
+ ret = clk_hw_register(NULL, &slowck->hw);
+ if (ret) {
+ kfree(slowck);
+ hw = ERR_PTR(ret);
+ }
+
+ return hw;
+}
+
+static void __init
+of_at91sam9x5_clk_slow_setup(struct device_node *np, void __iomem *sckcr)
+{
+ struct clk_hw *hw;
+ const char *parent_names[2];
+ unsigned int num_parents;
+ const char *name = np->name;
+
+ num_parents = of_clk_get_parent_count(np);
+ if (num_parents == 0 || num_parents > 2)
+ return;
+
+ of_clk_parent_fill(np, parent_names, num_parents);
+
+ of_property_read_string(np, "clock-output-names", &name);
+
+ hw = at91_clk_register_sam9x5_slow(sckcr, name, parent_names,
+ num_parents);
+ if (IS_ERR(hw))
+ return;
+
+ of_clk_add_hw_provider(np, of_clk_hw_simple_get, hw);
+}
static const struct of_device_id sckc_clk_ids[] __initconst = {
/* Slow clock */
@@ -55,3 +426,94 @@ static void __init of_at91sam9x5_sckc_setup(struct device_node *np)
}
CLK_OF_DECLARE(at91sam9x5_clk_sckc, "atmel,at91sam9x5-sckc",
of_at91sam9x5_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 aready passed.
+ */
+ if ((readl(osc->sckcr) & AT91_SCKC_OSCSEL)) {
+ osc->prepared = true;
+ return 0;
+ }
+
+ 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 void __init of_sama5d4_sckc_setup(struct device_node *np)
+{
+ void __iomem *regbase = of_iomap(np, 0);
+ struct clk_hw *hw;
+ 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" };
+ bool bypass;
+ int ret;
+
+ if (!regbase)
+ return;
+
+ hw = clk_hw_register_fixed_rate_with_accuracy(NULL, parent_names[0],
+ NULL, 0, 32768,
+ 250000000);
+ if (IS_ERR(hw))
+ return;
+
+ xtal_name = of_clk_get_parent_name(np, 0);
+
+ bypass = of_property_read_bool(np, "atmel,osc-bypass");
+
+ osc = kzalloc(sizeof(*osc), GFP_KERNEL);
+ if (!osc)
+ return;
+
+ 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;
+
+ if (bypass)
+ writel((readl(regbase) | AT91_SCKC_OSC32BYP), regbase);
+
+ hw = &osc->hw;
+ ret = clk_hw_register(NULL, &osc->hw);
+ if (ret) {
+ kfree(osc);
+ return;
+ }
+
+ hw = at91_clk_register_sam9x5_slow(regbase, "slowck", parent_names, 2);
+ if (IS_ERR(hw))
+ return;
+
+ of_clk_add_hw_provider(np, of_clk_hw_simple_get, hw);
+}
+CLK_OF_DECLARE(sama5d4_clk_sckc, "atmel,sama5d4-sckc",
+ of_sama5d4_sckc_setup);