clk: at91: clk-peripheral: add driver compatible with ccf

Add clk-peripheral compatible with common clock framework.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>

3 files changed, 272 insertions, 0 deletions

diff --git a/drivers/clk/at91/Makefile b/drivers/clk/at91/Makefile
index 1d59531e0c..b5529065b5 100644
--- a/drivers/clk/at91/Makefile
+++ b/drivers/clk/at91/Makefile
@@ -4,6 +4,8 @@
 
 ifdef CONFIG_CLK_CCF
 obj-y += pmc.o sckc.o clk-main.o clk-master.o clk-programmable.o clk-system.o
+obj-y += clk-peripheral.o
+
 obj-$(CONFIG_AT91_UTMI)		+= clk-utmi.o
 obj-$(CONFIG_AT91_SAM9X60_PLL)	+= clk-sam9x60-pll.o
 else
diff --git a/drivers/clk/at91/clk-peripheral.c b/drivers/clk/at91/clk-peripheral.c
new file mode 100644
index 0000000000..52cbc520ce
--- /dev/null
+++ b/drivers/clk/at91/clk-peripheral.c
@@ -0,0 +1,254 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Peripheral clock support for AT91 architectures.
+ *
+ * Copyright (C) 2020 Microchip Technology Inc. and its subsidiaries
+ *
+ * Author: Claudiu Beznea <claudiu.beznea@microchip.com>
+ *
+ * Based on drivers/clk/at91/clk-peripheral.c from Linux.
+ */
+#include <common.h>
+#include <clk-uclass.h>
+#include <dm.h>
+#include <linux/io.h>
+#include <linux/clk-provider.h>
+#include <linux/clk/at91_pmc.h>
+
+#include "pmc.h"
+
+#define UBOOT_DM_CLK_AT91_PERIPH		"at91-periph-clk"
+#define UBOOT_DM_CLK_AT91_SAM9X5_PERIPH		"at91-sam9x5-periph-clk"
+
+#define PERIPHERAL_ID_MIN	2
+#define PERIPHERAL_ID_MAX	31
+#define PERIPHERAL_MASK(id)	(1 << ((id) & PERIPHERAL_ID_MAX))
+
+#define PERIPHERAL_MAX_SHIFT	3
+
+struct clk_peripheral {
+	void __iomem *base;
+	struct clk clk;
+	u32 id;
+};
+
+#define to_clk_peripheral(_c) container_of(_c, struct clk_peripheral, clk)
+
+struct clk_sam9x5_peripheral {
+	const struct clk_pcr_layout *layout;
+	void __iomem *base;
+	struct clk clk;
+	struct clk_range range;
+	u32 id;
+	u32 div;
+	bool auto_div;
+};
+
+#define to_clk_sam9x5_peripheral(_c) \
+	container_of(_c, struct clk_sam9x5_peripheral, clk)
+
+static int clk_peripheral_enable(struct clk *clk)
+{
+	struct clk_peripheral *periph = to_clk_peripheral(clk);
+	int offset = AT91_PMC_PCER;
+	u32 id = periph->id;
+
+	if (id < PERIPHERAL_ID_MIN)
+		return 0;
+	if (id > PERIPHERAL_ID_MAX)
+		offset = AT91_PMC_PCER1;
+	pmc_write(periph->base, offset, PERIPHERAL_MASK(id));
+
+	return 0;
+}
+
+static int clk_peripheral_disable(struct clk *clk)
+{
+	struct clk_peripheral *periph = to_clk_peripheral(clk);
+	int offset = AT91_PMC_PCDR;
+	u32 id = periph->id;
+
+	if (id < PERIPHERAL_ID_MIN)
+		return -EINVAL;
+
+	if (id > PERIPHERAL_ID_MAX)
+		offset = AT91_PMC_PCDR1;
+	pmc_write(periph->base, offset, PERIPHERAL_MASK(id));
+
+	return 0;
+}
+
+static const struct clk_ops peripheral_ops = {
+	.enable = clk_peripheral_enable,
+	.disable = clk_peripheral_disable,
+	.get_rate = clk_generic_get_rate,
+};
+
+struct clk *
+at91_clk_register_peripheral(void __iomem *base, const char *name,
+			     const char *parent_name, u32 id)
+{
+	struct clk_peripheral *periph;
+	struct clk *clk;
+	int ret;
+
+	if (!base || !name || !parent_name || id > PERIPHERAL_ID_MAX)
+		return ERR_PTR(-EINVAL);
+
+	periph = kzalloc(sizeof(*periph), GFP_KERNEL);
+	if (!periph)
+		return ERR_PTR(-ENOMEM);
+
+	periph->id = id;
+	periph->base = base;
+
+	clk = &periph->clk;
+	clk->flags = CLK_GET_RATE_NOCACHE;
+	ret = clk_register(clk, UBOOT_DM_CLK_AT91_PERIPH, name, parent_name);
+	if (ret) {
+		kfree(periph);
+		clk = ERR_PTR(ret);
+	}
+
+	return clk;
+}
+
+U_BOOT_DRIVER(at91_periph_clk) = {
+	.name = UBOOT_DM_CLK_AT91_PERIPH,
+	.id = UCLASS_CLK,
+	.ops = &peripheral_ops,
+	.flags = DM_FLAG_PRE_RELOC,
+};
+
+static int clk_sam9x5_peripheral_enable(struct clk *clk)
+{
+	struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(clk);
+
+	if (periph->id < PERIPHERAL_ID_MIN)
+		return 0;
+
+	pmc_write(periph->base, periph->layout->offset,
+		  (periph->id & periph->layout->pid_mask));
+	pmc_update_bits(periph->base, periph->layout->offset,
+			periph->layout->cmd | AT91_PMC_PCR_EN,
+			periph->layout->cmd | AT91_PMC_PCR_EN);
+
+	return 0;
+}
+
+static int clk_sam9x5_peripheral_disable(struct clk *clk)
+{
+	struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(clk);
+
+	if (periph->id < PERIPHERAL_ID_MIN)
+		return -EINVAL;
+
+	pmc_write(periph->base, periph->layout->offset,
+		  (periph->id & periph->layout->pid_mask));
+	pmc_update_bits(periph->base, periph->layout->offset,
+			AT91_PMC_PCR_EN | periph->layout->cmd,
+			periph->layout->cmd);
+
+	return 0;
+}
+
+static ulong clk_sam9x5_peripheral_get_rate(struct clk *clk)
+{
+	struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(clk);
+	ulong parent_rate = clk_get_parent_rate(clk);
+	u32 val, shift = ffs(periph->layout->div_mask) - 1;
+
+	if (!parent_rate)
+		return 0;
+
+	pmc_write(periph->base, periph->layout->offset,
+		  (periph->id & periph->layout->pid_mask));
+	pmc_read(periph->base, periph->layout->offset, &val);
+	shift = (val & periph->layout->div_mask) >> shift;
+
+	return parent_rate >> shift;
+}
+
+static ulong clk_sam9x5_peripheral_set_rate(struct clk *clk, ulong rate)
+{
+	struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(clk);
+	ulong parent_rate = clk_get_parent_rate(clk);
+	int shift;
+
+	if (!parent_rate)
+		return 0;
+
+	if (periph->id < PERIPHERAL_ID_MIN || !periph->range.max) {
+		if (parent_rate == rate)
+			return rate;
+		else
+			return 0;
+	}
+
+	if (periph->range.max && rate > periph->range.max)
+		return 0;
+
+	for (shift = 0; shift <= PERIPHERAL_MAX_SHIFT; shift++) {
+		if (parent_rate >> shift <= rate)
+			break;
+	}
+	if (shift == PERIPHERAL_MAX_SHIFT + 1)
+		return 0;
+
+	pmc_write(periph->base, periph->layout->offset,
+		  (periph->id & periph->layout->pid_mask));
+	pmc_update_bits(periph->base, periph->layout->offset,
+			periph->layout->div_mask | periph->layout->cmd,
+			(shift << (ffs(periph->layout->div_mask) - 1)) |
+			periph->layout->cmd);
+
+	return parent_rate >> shift;
+}
+
+static const struct clk_ops sam9x5_peripheral_ops = {
+	.enable = clk_sam9x5_peripheral_enable,
+	.disable = clk_sam9x5_peripheral_disable,
+	.get_rate = clk_sam9x5_peripheral_get_rate,
+	.set_rate = clk_sam9x5_peripheral_set_rate,
+};
+
+struct clk *
+at91_clk_register_sam9x5_peripheral(void __iomem *base,
+				    const struct clk_pcr_layout *layout,
+				    const char *name, const char *parent_name,
+				    u32 id, const struct clk_range *range)
+{
+	struct clk_sam9x5_peripheral *periph;
+	struct clk *clk;
+	int ret;
+
+	if (!base || !layout || !name || !parent_name || !range)
+		return ERR_PTR(-EINVAL);
+
+	periph = kzalloc(sizeof(*periph), GFP_KERNEL);
+	if (!periph)
+		return ERR_PTR(-ENOMEM);
+
+	periph->id = id;
+	periph->base = base;
+	periph->layout = layout;
+	periph->range = *range;
+
+	clk = &periph->clk;
+	clk->flags = CLK_GET_RATE_NOCACHE;
+	ret = clk_register(clk, UBOOT_DM_CLK_AT91_SAM9X5_PERIPH, name,
+			   parent_name);
+	if (ret) {
+		kfree(periph);
+		clk = ERR_PTR(ret);
+	}
+
+	return clk;
+}
+
+U_BOOT_DRIVER(at91_sam9x5_periph_clk) = {
+	.name = UBOOT_DM_CLK_AT91_SAM9X5_PERIPH,
+	.id = UCLASS_CLK,
+	.ops = &sam9x5_peripheral_ops,
+	.flags = DM_FLAG_PRE_RELOC,
+};
diff --git a/drivers/clk/at91/pmc.h b/drivers/clk/at91/pmc.h
index c372f39fc9..5e80f353e6 100644
--- a/drivers/clk/at91/pmc.h
+++ b/drivers/clk/at91/pmc.h
@@ -63,6 +63,14 @@ struct clk_programmable_layout {
 	u8 is_pres_direct;
 };
 
+struct clk_pcr_layout {
+	u32 offset;
+	u32 cmd;
+	u32 div_mask;
+	u32 gckcss_mask;
+	u32 pid_mask;
+};
+
 extern const struct clk_programmable_layout at91rm9200_programmable_layout;
 extern const struct clk_programmable_layout at91sam9g45_programmable_layout;
 extern const struct clk_programmable_layout at91sam9x5_programmable_layout;
@@ -111,6 +119,14 @@ at91_clk_register_programmable(void __iomem *base, const char *name,
 struct clk *
 at91_clk_register_system(void __iomem *base, const char *name,
 			const char *parent_name, u8 id);
+struct clk *
+at91_clk_register_peripheral(void __iomem *base, const char *name,
+			const char *parent_name, u32 id);
+struct clk *
+at91_clk_register_sam9x5_peripheral(void __iomem *base,
+			const struct clk_pcr_layout *layout,
+			const char *name, const char *parent_name,
+			u32 id, const struct clk_range *range);
 
 int at91_clk_mux_val_to_index(const u32 *table, u32 num_parents, u32 val);
 int at91_clk_mux_index_to_val(const u32 *table, u32 num_parents, u32 index);