Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 202 insertions, 0 deletions

diff --git a/drivers/clk/at91/clk-utmi.c b/drivers/clk/at91/clk-utmi.c
new file mode 100644
index 000000000..cd8d68913
--- /dev/null
+++ b/drivers/clk/at91/clk-utmi.c
@@ -0,0 +1,202 @@
+/*
+ *  Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/clk/at91_pmc.h>
+#include <linux/of.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+#include <soc/at91/atmel-sfr.h>
+
+#include "pmc.h"
+
+/*
+ * The purpose of this clock is to generate a 480 MHz signal. A different
+ * rate can't be configured.
+ */
+#define UTMI_RATE	480000000
+
+struct clk_utmi {
+	struct clk_hw hw;
+	struct regmap *regmap_pmc;
+	struct regmap *regmap_sfr;
+};
+
+#define to_clk_utmi(hw) container_of(hw, struct clk_utmi, hw)
+
+static inline bool clk_utmi_ready(struct regmap *regmap)
+{
+	unsigned int status;
+
+	regmap_read(regmap, AT91_PMC_SR, &status);
+
+	return status & AT91_PMC_LOCKU;
+}
+
+static int clk_utmi_prepare(struct clk_hw *hw)
+{
+	struct clk_hw *hw_parent;
+	struct clk_utmi *utmi = to_clk_utmi(hw);
+	unsigned int uckr = AT91_PMC_UPLLEN | AT91_PMC_UPLLCOUNT |
+			    AT91_PMC_BIASEN;
+	unsigned int utmi_ref_clk_freq;
+	unsigned long parent_rate;
+
+	/*
+	 * If mainck rate is different from 12 MHz, we have to configure the
+	 * FREQ field of the SFR_UTMICKTRIM register to generate properly
+	 * the utmi clock.
+	 */
+	hw_parent = clk_hw_get_parent(hw);
+	parent_rate = clk_hw_get_rate(hw_parent);
+
+	switch (parent_rate) {
+	case 12000000:
+		utmi_ref_clk_freq = 0;
+		break;
+	case 16000000:
+		utmi_ref_clk_freq = 1;
+		break;
+	case 24000000:
+		utmi_ref_clk_freq = 2;
+		break;
+	/*
+	 * Not supported on SAMA5D2 but it's not an issue since MAINCK
+	 * maximum value is 24 MHz.
+	 */
+	case 48000000:
+		utmi_ref_clk_freq = 3;
+		break;
+	default:
+		pr_err("UTMICK: unsupported mainck rate\n");
+		return -EINVAL;
+	}
+
+	if (utmi->regmap_sfr) {
+		regmap_update_bits(utmi->regmap_sfr, AT91_SFR_UTMICKTRIM,
+				   AT91_UTMICKTRIM_FREQ, utmi_ref_clk_freq);
+	} else if (utmi_ref_clk_freq) {
+		pr_err("UTMICK: sfr node required\n");
+		return -EINVAL;
+	}
+
+	regmap_update_bits(utmi->regmap_pmc, AT91_CKGR_UCKR, uckr, uckr);
+
+	while (!clk_utmi_ready(utmi->regmap_pmc))
+		cpu_relax();
+
+	return 0;
+}
+
+static int clk_utmi_is_prepared(struct clk_hw *hw)
+{
+	struct clk_utmi *utmi = to_clk_utmi(hw);
+
+	return clk_utmi_ready(utmi->regmap_pmc);
+}
+
+static void clk_utmi_unprepare(struct clk_hw *hw)
+{
+	struct clk_utmi *utmi = to_clk_utmi(hw);
+
+	regmap_update_bits(utmi->regmap_pmc, AT91_CKGR_UCKR,
+			   AT91_PMC_UPLLEN, 0);
+}
+
+static unsigned long clk_utmi_recalc_rate(struct clk_hw *hw,
+					  unsigned long parent_rate)
+{
+	/* UTMI clk rate is fixed. */
+	return UTMI_RATE;
+}
+
+static const struct clk_ops utmi_ops = {
+	.prepare = clk_utmi_prepare,
+	.unprepare = clk_utmi_unprepare,
+	.is_prepared = clk_utmi_is_prepared,
+	.recalc_rate = clk_utmi_recalc_rate,
+};
+
+static struct clk_hw * __init
+at91_clk_register_utmi(struct regmap *regmap_pmc, struct regmap *regmap_sfr,
+		       const char *name, const char *parent_name)
+{
+	struct clk_utmi *utmi;
+	struct clk_hw *hw;
+	struct clk_init_data init;
+	int ret;
+
+	utmi = kzalloc(sizeof(*utmi), GFP_KERNEL);
+	if (!utmi)
+		return ERR_PTR(-ENOMEM);
+
+	init.name = name;
+	init.ops = &utmi_ops;
+	init.parent_names = parent_name ? &parent_name : NULL;
+	init.num_parents = parent_name ? 1 : 0;
+	init.flags = CLK_SET_RATE_GATE;
+
+	utmi->hw.init = &init;
+	utmi->regmap_pmc = regmap_pmc;
+	utmi->regmap_sfr = regmap_sfr;
+
+	hw = &utmi->hw;
+	ret = clk_hw_register(NULL, &utmi->hw);
+	if (ret) {
+		kfree(utmi);
+		hw = ERR_PTR(ret);
+	}
+
+	return hw;
+}
+
+static void __init of_at91sam9x5_clk_utmi_setup(struct device_node *np)
+{
+	struct clk_hw *hw;
+	const char *parent_name;
+	const char *name = np->name;
+	struct regmap *regmap_pmc, *regmap_sfr;
+
+	parent_name = of_clk_get_parent_name(np, 0);
+
+	of_property_read_string(np, "clock-output-names", &name);
+
+	regmap_pmc = syscon_node_to_regmap(of_get_parent(np));
+	if (IS_ERR(regmap_pmc))
+		return;
+
+	/*
+	 * If the device supports different mainck rates, this value has to be
+	 * set in the UTMI Clock Trimming register.
+	 * - 9x5: mainck supports several rates but it is indicated that a
+	 *   12 MHz is needed in case of USB.
+	 * - sama5d3 and sama5d2: mainck supports several rates. Configuring
+	 *   the FREQ field of the UTMI Clock Trimming register is mandatory.
+	 * - sama5d4: mainck is at 12 MHz.
+	 *
+	 * We only need to retrieve sama5d3 or sama5d2 sfr regmap.
+	 */
+	regmap_sfr = syscon_regmap_lookup_by_compatible("atmel,sama5d3-sfr");
+	if (IS_ERR(regmap_sfr)) {
+		regmap_sfr = syscon_regmap_lookup_by_compatible("atmel,sama5d2-sfr");
+		if (IS_ERR(regmap_sfr))
+			regmap_sfr = NULL;
+	}
+
+	hw = at91_clk_register_utmi(regmap_pmc, regmap_sfr, name, parent_name);
+	if (IS_ERR(hw))
+		return;
+
+	of_clk_add_hw_provider(np, of_clk_hw_simple_get, hw);
+	return;
+}
+CLK_OF_DECLARE(at91sam9x5_clk_utmi, "atmel,at91sam9x5-clk-utmi",
+	       of_at91sam9x5_clk_utmi_setup);