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-rw-r--r--drivers/clk/at91/clk-main.c517
1 files changed, 517 insertions, 0 deletions
diff --git a/drivers/clk/at91/clk-main.c b/drivers/clk/at91/clk-main.c
new file mode 100644
index 000000000..cfae2f59d
--- /dev/null
+++ b/drivers/clk/at91/clk-main.c
@@ -0,0 +1,517 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/clk/at91_pmc.h>
+#include <linux/delay.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+
+#include "pmc.h"
+
+#define SLOW_CLOCK_FREQ 32768
+#define MAINF_DIV 16
+#define MAINFRDY_TIMEOUT (((MAINF_DIV + 1) * USEC_PER_SEC) / \
+ SLOW_CLOCK_FREQ)
+#define MAINF_LOOP_MIN_WAIT (USEC_PER_SEC / SLOW_CLOCK_FREQ)
+#define MAINF_LOOP_MAX_WAIT MAINFRDY_TIMEOUT
+
+#define MOR_KEY_MASK (0xff << 16)
+
+#define clk_main_parent_select(s) (((s) & \
+ (AT91_PMC_MOSCEN | \
+ AT91_PMC_OSCBYPASS)) ? 1 : 0)
+
+struct clk_main_osc {
+ struct clk_hw hw;
+ struct regmap *regmap;
+};
+
+#define to_clk_main_osc(hw) container_of(hw, struct clk_main_osc, hw)
+
+struct clk_main_rc_osc {
+ struct clk_hw hw;
+ struct regmap *regmap;
+ unsigned long frequency;
+ unsigned long accuracy;
+};
+
+#define to_clk_main_rc_osc(hw) container_of(hw, struct clk_main_rc_osc, hw)
+
+struct clk_rm9200_main {
+ struct clk_hw hw;
+ struct regmap *regmap;
+};
+
+#define to_clk_rm9200_main(hw) container_of(hw, struct clk_rm9200_main, hw)
+
+struct clk_sam9x5_main {
+ struct clk_hw hw;
+ struct regmap *regmap;
+ u8 parent;
+};
+
+#define to_clk_sam9x5_main(hw) container_of(hw, struct clk_sam9x5_main, hw)
+
+static inline bool clk_main_osc_ready(struct regmap *regmap)
+{
+ unsigned int status;
+
+ regmap_read(regmap, AT91_PMC_SR, &status);
+
+ return status & AT91_PMC_MOSCS;
+}
+
+static int clk_main_osc_prepare(struct clk_hw *hw)
+{
+ struct clk_main_osc *osc = to_clk_main_osc(hw);
+ struct regmap *regmap = osc->regmap;
+ u32 tmp;
+
+ regmap_read(regmap, AT91_CKGR_MOR, &tmp);
+ tmp &= ~MOR_KEY_MASK;
+
+ if (tmp & AT91_PMC_OSCBYPASS)
+ return 0;
+
+ if (!(tmp & AT91_PMC_MOSCEN)) {
+ tmp |= AT91_PMC_MOSCEN | AT91_PMC_KEY;
+ regmap_write(regmap, AT91_CKGR_MOR, tmp);
+ }
+
+ while (!clk_main_osc_ready(regmap))
+ cpu_relax();
+
+ return 0;
+}
+
+static void clk_main_osc_unprepare(struct clk_hw *hw)
+{
+ struct clk_main_osc *osc = to_clk_main_osc(hw);
+ struct regmap *regmap = osc->regmap;
+ u32 tmp;
+
+ regmap_read(regmap, AT91_CKGR_MOR, &tmp);
+ if (tmp & AT91_PMC_OSCBYPASS)
+ return;
+
+ if (!(tmp & AT91_PMC_MOSCEN))
+ return;
+
+ tmp &= ~(AT91_PMC_KEY | AT91_PMC_MOSCEN);
+ regmap_write(regmap, AT91_CKGR_MOR, tmp | AT91_PMC_KEY);
+}
+
+static int clk_main_osc_is_prepared(struct clk_hw *hw)
+{
+ struct clk_main_osc *osc = to_clk_main_osc(hw);
+ struct regmap *regmap = osc->regmap;
+ u32 tmp, status;
+
+ regmap_read(regmap, AT91_CKGR_MOR, &tmp);
+ if (tmp & AT91_PMC_OSCBYPASS)
+ return 1;
+
+ regmap_read(regmap, AT91_PMC_SR, &status);
+
+ return (status & AT91_PMC_MOSCS) && clk_main_parent_select(tmp);
+}
+
+static const struct clk_ops main_osc_ops = {
+ .prepare = clk_main_osc_prepare,
+ .unprepare = clk_main_osc_unprepare,
+ .is_prepared = clk_main_osc_is_prepared,
+};
+
+struct clk_hw * __init
+at91_clk_register_main_osc(struct regmap *regmap,
+ const char *name,
+ const char *parent_name,
+ bool bypass)
+{
+ struct clk_main_osc *osc;
+ struct clk_init_data init;
+ struct clk_hw *hw;
+ int ret;
+
+ if (!name || !parent_name)
+ return ERR_PTR(-EINVAL);
+
+ osc = kzalloc(sizeof(*osc), GFP_KERNEL);
+ if (!osc)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &main_osc_ops;
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
+ init.flags = CLK_IGNORE_UNUSED;
+
+ osc->hw.init = &init;
+ osc->regmap = regmap;
+
+ if (bypass)
+ regmap_update_bits(regmap,
+ AT91_CKGR_MOR, MOR_KEY_MASK |
+ AT91_PMC_OSCBYPASS,
+ AT91_PMC_OSCBYPASS | AT91_PMC_KEY);
+
+ hw = &osc->hw;
+ ret = clk_hw_register(NULL, &osc->hw);
+ if (ret) {
+ kfree(osc);
+ hw = ERR_PTR(ret);
+ }
+
+ return hw;
+}
+
+static bool clk_main_rc_osc_ready(struct regmap *regmap)
+{
+ unsigned int status;
+
+ regmap_read(regmap, AT91_PMC_SR, &status);
+
+ return !!(status & AT91_PMC_MOSCRCS);
+}
+
+static int clk_main_rc_osc_prepare(struct clk_hw *hw)
+{
+ struct clk_main_rc_osc *osc = to_clk_main_rc_osc(hw);
+ struct regmap *regmap = osc->regmap;
+ unsigned int mor;
+
+ regmap_read(regmap, AT91_CKGR_MOR, &mor);
+
+ if (!(mor & AT91_PMC_MOSCRCEN))
+ regmap_update_bits(regmap, AT91_CKGR_MOR,
+ MOR_KEY_MASK | AT91_PMC_MOSCRCEN,
+ AT91_PMC_MOSCRCEN | AT91_PMC_KEY);
+
+ while (!clk_main_rc_osc_ready(regmap))
+ cpu_relax();
+
+ return 0;
+}
+
+static void clk_main_rc_osc_unprepare(struct clk_hw *hw)
+{
+ struct clk_main_rc_osc *osc = to_clk_main_rc_osc(hw);
+ struct regmap *regmap = osc->regmap;
+ unsigned int mor;
+
+ regmap_read(regmap, AT91_CKGR_MOR, &mor);
+
+ if (!(mor & AT91_PMC_MOSCRCEN))
+ return;
+
+ regmap_update_bits(regmap, AT91_CKGR_MOR,
+ MOR_KEY_MASK | AT91_PMC_MOSCRCEN, AT91_PMC_KEY);
+}
+
+static int clk_main_rc_osc_is_prepared(struct clk_hw *hw)
+{
+ struct clk_main_rc_osc *osc = to_clk_main_rc_osc(hw);
+ struct regmap *regmap = osc->regmap;
+ unsigned int mor, status;
+
+ regmap_read(regmap, AT91_CKGR_MOR, &mor);
+ regmap_read(regmap, AT91_PMC_SR, &status);
+
+ return (mor & AT91_PMC_MOSCRCEN) && (status & AT91_PMC_MOSCRCS);
+}
+
+static unsigned long clk_main_rc_osc_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_main_rc_osc *osc = to_clk_main_rc_osc(hw);
+
+ return osc->frequency;
+}
+
+static unsigned long clk_main_rc_osc_recalc_accuracy(struct clk_hw *hw,
+ unsigned long parent_acc)
+{
+ struct clk_main_rc_osc *osc = to_clk_main_rc_osc(hw);
+
+ return osc->accuracy;
+}
+
+static const struct clk_ops main_rc_osc_ops = {
+ .prepare = clk_main_rc_osc_prepare,
+ .unprepare = clk_main_rc_osc_unprepare,
+ .is_prepared = clk_main_rc_osc_is_prepared,
+ .recalc_rate = clk_main_rc_osc_recalc_rate,
+ .recalc_accuracy = clk_main_rc_osc_recalc_accuracy,
+};
+
+struct clk_hw * __init
+at91_clk_register_main_rc_osc(struct regmap *regmap,
+ const char *name,
+ u32 frequency, u32 accuracy)
+{
+ struct clk_main_rc_osc *osc;
+ struct clk_init_data init;
+ struct clk_hw *hw;
+ int ret;
+
+ if (!name || !frequency)
+ return ERR_PTR(-EINVAL);
+
+ osc = kzalloc(sizeof(*osc), GFP_KERNEL);
+ if (!osc)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &main_rc_osc_ops;
+ init.parent_names = NULL;
+ init.num_parents = 0;
+ init.flags = CLK_IGNORE_UNUSED;
+
+ osc->hw.init = &init;
+ osc->regmap = regmap;
+ osc->frequency = frequency;
+ osc->accuracy = accuracy;
+
+ hw = &osc->hw;
+ ret = clk_hw_register(NULL, hw);
+ if (ret) {
+ kfree(osc);
+ hw = ERR_PTR(ret);
+ }
+
+ return hw;
+}
+
+static int clk_main_probe_frequency(struct regmap *regmap)
+{
+ unsigned long prep_time, timeout;
+ unsigned int mcfr;
+
+ timeout = jiffies + usecs_to_jiffies(MAINFRDY_TIMEOUT);
+ do {
+ prep_time = jiffies;
+ regmap_read(regmap, AT91_CKGR_MCFR, &mcfr);
+ if (mcfr & AT91_PMC_MAINRDY)
+ return 0;
+ if (system_state < SYSTEM_RUNNING)
+ udelay(MAINF_LOOP_MIN_WAIT);
+ else
+ usleep_range(MAINF_LOOP_MIN_WAIT, MAINF_LOOP_MAX_WAIT);
+ } while (time_before(prep_time, timeout));
+
+ return -ETIMEDOUT;
+}
+
+static unsigned long clk_main_recalc_rate(struct regmap *regmap,
+ unsigned long parent_rate)
+{
+ unsigned int mcfr;
+
+ if (parent_rate)
+ return parent_rate;
+
+ pr_warn("Main crystal frequency not set, using approximate value\n");
+ regmap_read(regmap, AT91_CKGR_MCFR, &mcfr);
+ if (!(mcfr & AT91_PMC_MAINRDY))
+ return 0;
+
+ return ((mcfr & AT91_PMC_MAINF) * SLOW_CLOCK_FREQ) / MAINF_DIV;
+}
+
+static int clk_rm9200_main_prepare(struct clk_hw *hw)
+{
+ struct clk_rm9200_main *clkmain = to_clk_rm9200_main(hw);
+
+ return clk_main_probe_frequency(clkmain->regmap);
+}
+
+static int clk_rm9200_main_is_prepared(struct clk_hw *hw)
+{
+ struct clk_rm9200_main *clkmain = to_clk_rm9200_main(hw);
+ unsigned int status;
+
+ regmap_read(clkmain->regmap, AT91_CKGR_MCFR, &status);
+
+ return !!(status & AT91_PMC_MAINRDY);
+}
+
+static unsigned long clk_rm9200_main_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_rm9200_main *clkmain = to_clk_rm9200_main(hw);
+
+ return clk_main_recalc_rate(clkmain->regmap, parent_rate);
+}
+
+static const struct clk_ops rm9200_main_ops = {
+ .prepare = clk_rm9200_main_prepare,
+ .is_prepared = clk_rm9200_main_is_prepared,
+ .recalc_rate = clk_rm9200_main_recalc_rate,
+};
+
+struct clk_hw * __init
+at91_clk_register_rm9200_main(struct regmap *regmap,
+ const char *name,
+ const char *parent_name)
+{
+ struct clk_rm9200_main *clkmain;
+ struct clk_init_data init;
+ struct clk_hw *hw;
+ int ret;
+
+ if (!name)
+ return ERR_PTR(-EINVAL);
+
+ if (!parent_name)
+ return ERR_PTR(-EINVAL);
+
+ clkmain = kzalloc(sizeof(*clkmain), GFP_KERNEL);
+ if (!clkmain)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &rm9200_main_ops;
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
+ init.flags = 0;
+
+ clkmain->hw.init = &init;
+ clkmain->regmap = regmap;
+
+ hw = &clkmain->hw;
+ ret = clk_hw_register(NULL, &clkmain->hw);
+ if (ret) {
+ kfree(clkmain);
+ hw = ERR_PTR(ret);
+ }
+
+ return hw;
+}
+
+static inline bool clk_sam9x5_main_ready(struct regmap *regmap)
+{
+ unsigned int status;
+
+ regmap_read(regmap, AT91_PMC_SR, &status);
+
+ return !!(status & AT91_PMC_MOSCSELS);
+}
+
+static int clk_sam9x5_main_prepare(struct clk_hw *hw)
+{
+ struct clk_sam9x5_main *clkmain = to_clk_sam9x5_main(hw);
+ struct regmap *regmap = clkmain->regmap;
+
+ while (!clk_sam9x5_main_ready(regmap))
+ cpu_relax();
+
+ return clk_main_probe_frequency(regmap);
+}
+
+static int clk_sam9x5_main_is_prepared(struct clk_hw *hw)
+{
+ struct clk_sam9x5_main *clkmain = to_clk_sam9x5_main(hw);
+
+ return clk_sam9x5_main_ready(clkmain->regmap);
+}
+
+static unsigned long clk_sam9x5_main_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_sam9x5_main *clkmain = to_clk_sam9x5_main(hw);
+
+ return clk_main_recalc_rate(clkmain->regmap, parent_rate);
+}
+
+static int clk_sam9x5_main_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct clk_sam9x5_main *clkmain = to_clk_sam9x5_main(hw);
+ struct regmap *regmap = clkmain->regmap;
+ unsigned int tmp;
+
+ if (index > 1)
+ return -EINVAL;
+
+ regmap_read(regmap, AT91_CKGR_MOR, &tmp);
+
+ if (index && !(tmp & AT91_PMC_MOSCSEL))
+ tmp = AT91_PMC_MOSCSEL;
+ else if (!index && (tmp & AT91_PMC_MOSCSEL))
+ tmp = 0;
+ else
+ return 0;
+
+ regmap_update_bits(regmap, AT91_CKGR_MOR,
+ AT91_PMC_MOSCSEL | MOR_KEY_MASK,
+ tmp | AT91_PMC_KEY);
+
+ while (!clk_sam9x5_main_ready(regmap))
+ cpu_relax();
+
+ return 0;
+}
+
+static u8 clk_sam9x5_main_get_parent(struct clk_hw *hw)
+{
+ struct clk_sam9x5_main *clkmain = to_clk_sam9x5_main(hw);
+ unsigned int status;
+
+ regmap_read(clkmain->regmap, AT91_CKGR_MOR, &status);
+
+ return clk_main_parent_select(status);
+}
+
+static const struct clk_ops sam9x5_main_ops = {
+ .prepare = clk_sam9x5_main_prepare,
+ .is_prepared = clk_sam9x5_main_is_prepared,
+ .recalc_rate = clk_sam9x5_main_recalc_rate,
+ .set_parent = clk_sam9x5_main_set_parent,
+ .get_parent = clk_sam9x5_main_get_parent,
+};
+
+struct clk_hw * __init
+at91_clk_register_sam9x5_main(struct regmap *regmap,
+ const char *name,
+ const char **parent_names,
+ int num_parents)
+{
+ struct clk_sam9x5_main *clkmain;
+ struct clk_init_data init;
+ unsigned int status;
+ struct clk_hw *hw;
+ int ret;
+
+ if (!name)
+ return ERR_PTR(-EINVAL);
+
+ if (!parent_names || !num_parents)
+ return ERR_PTR(-EINVAL);
+
+ clkmain = kzalloc(sizeof(*clkmain), GFP_KERNEL);
+ if (!clkmain)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &sam9x5_main_ops;
+ init.parent_names = parent_names;
+ init.num_parents = num_parents;
+ init.flags = CLK_SET_PARENT_GATE;
+
+ clkmain->hw.init = &init;
+ clkmain->regmap = regmap;
+ regmap_read(clkmain->regmap, AT91_CKGR_MOR, &status);
+ clkmain->parent = clk_main_parent_select(status);
+
+ hw = &clkmain->hw;
+ ret = clk_hw_register(NULL, &clkmain->hw);
+ if (ret) {
+ kfree(clkmain);
+ hw = ERR_PTR(ret);
+ }
+
+ return hw;
+}