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-rw-r--r--drivers/clk/mvebu/Kconfig3
-rw-r--r--drivers/clk/mvebu/Makefile1
-rw-r--r--drivers/clk/mvebu/ap-cpu-clk.c259
3 files changed, 263 insertions, 0 deletions
diff --git a/drivers/clk/mvebu/Kconfig b/drivers/clk/mvebu/Kconfig
index 19f1b51ed15e..415e6906a113 100644
--- a/drivers/clk/mvebu/Kconfig
+++ b/drivers/clk/mvebu/Kconfig
@@ -40,6 +40,9 @@ config ARMADA_AP806_SYSCON
 	bool
 	select ARMADA_AP_CP_HELPER
 
+config ARMADA_AP_CPU_CLK
+	bool
+
 config ARMADA_CP110_SYSCON
 	bool
 	select ARMADA_AP_CP_HELPER
diff --git a/drivers/clk/mvebu/Makefile b/drivers/clk/mvebu/Makefile
index 6638ad962ec1..04464cef0f06 100644
--- a/drivers/clk/mvebu/Makefile
+++ b/drivers/clk/mvebu/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_ARMADA_37XX_CLK)	+= armada-37xx-tbg.o
 obj-$(CONFIG_ARMADA_37XX_CLK)	+= armada-37xx-periph.o
 obj-$(CONFIG_ARMADA_XP_CLK)	+= armada-xp.o mv98dx3236.o
 obj-$(CONFIG_ARMADA_AP806_SYSCON) += ap806-system-controller.o
+obj-$(CONFIG_ARMADA_AP_CPU_CLK) += ap-cpu-clk.o
 obj-$(CONFIG_ARMADA_CP110_SYSCON) += cp110-system-controller.o
 obj-$(CONFIG_DOVE_CLK)		+= dove.o dove-divider.o
 obj-$(CONFIG_KIRKWOOD_CLK)	+= kirkwood.o
diff --git a/drivers/clk/mvebu/ap-cpu-clk.c b/drivers/clk/mvebu/ap-cpu-clk.c
new file mode 100644
index 000000000000..e4cecb456884
--- /dev/null
+++ b/drivers/clk/mvebu/ap-cpu-clk.c
@@ -0,0 +1,259 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Marvell Armada AP CPU Clock Controller
+ *
+ * Copyright (C) 2018 Marvell
+ *
+ * Omri Itach <omrii@marvell.com>
+ * Gregory Clement <gregory.clement@bootlin.com>
+ */
+
+#define pr_fmt(fmt) "ap-cpu-clk: " fmt
+
+#include <linux/clk-provider.h>
+#include <linux/clk.h>
+#include <linux/mfd/syscon.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include "armada_ap_cp_helper.h"
+
+#define AP806_CPU_CLUSTER0		0
+#define AP806_CPU_CLUSTER1		1
+#define AP806_CPUS_PER_CLUSTER		2
+#define APN806_CPU1_MASK		0x1
+
+#define APN806_CLUSTER_NUM_OFFSET	8
+#define APN806_CLUSTER_NUM_MASK		BIT(APN806_CLUSTER_NUM_OFFSET)
+
+#define APN806_MAX_DIVIDER		32
+
+/* AP806 CPU DFS register mapping*/
+#define AP806_CA72MP2_0_PLL_CR_0_REG_OFFSET		0x278
+#define AP806_CA72MP2_0_PLL_CR_1_REG_OFFSET		0x280
+#define AP806_CA72MP2_0_PLL_CR_2_REG_OFFSET		0x284
+#define AP806_CA72MP2_0_PLL_SR_REG_OFFSET		0xC94
+
+#define AP806_CA72MP2_0_PLL_CR_CLUSTER_OFFSET		0x14
+#define AP806_PLL_CR_0_CPU_CLK_DIV_RATIO_OFFSET		0
+#define AP806_PLL_CR_0_CPU_CLK_DIV_RATIO_MASK \
+			(0x3f << AP806_PLL_CR_0_CPU_CLK_DIV_RATIO_OFFSET)
+#define AP806_PLL_CR_0_CPU_CLK_RELOAD_FORCE_OFFSET	24
+#define AP806_PLL_CR_0_CPU_CLK_RELOAD_FORCE_MASK \
+			(0x1 << AP806_PLL_CR_0_CPU_CLK_RELOAD_FORCE_OFFSET)
+#define AP806_PLL_CR_0_CPU_CLK_RELOAD_RATIO_OFFSET	16
+#define AP806_CA72MP2_0_PLL_RATIO_STATE			11
+
+#define STATUS_POLL_PERIOD_US		1
+#define STATUS_POLL_TIMEOUT_US		1000000
+
+#define to_ap_cpu_clk(_hw) container_of(_hw, struct ap_cpu_clk, hw)
+
+/*
+ * struct ap806_clk: CPU cluster clock controller instance
+ * @cluster: Cluster clock controller index
+ * @clk_name: Cluster clock controller name
+ * @dev : Cluster clock device
+ * @hw: HW specific structure of Cluster clock controller
+ * @pll_cr_base: CA72MP2 Register base (Device Sample at Reset register)
+ */
+struct ap_cpu_clk {
+	unsigned int cluster;
+	const char *clk_name;
+	struct device *dev;
+	struct clk_hw hw;
+	struct regmap *pll_cr_base;
+};
+
+static unsigned long ap_cpu_clk_recalc_rate(struct clk_hw *hw,
+					    unsigned long parent_rate)
+{
+	struct ap_cpu_clk *clk = to_ap_cpu_clk(hw);
+	unsigned int cpu_clkdiv_reg;
+	int cpu_clkdiv_ratio;
+
+	cpu_clkdiv_reg = AP806_CA72MP2_0_PLL_CR_0_REG_OFFSET +
+		(clk->cluster * AP806_CA72MP2_0_PLL_CR_CLUSTER_OFFSET);
+	regmap_read(clk->pll_cr_base, cpu_clkdiv_reg, &cpu_clkdiv_ratio);
+	cpu_clkdiv_ratio &= AP806_PLL_CR_0_CPU_CLK_DIV_RATIO_MASK;
+	cpu_clkdiv_ratio >>= AP806_PLL_CR_0_CPU_CLK_DIV_RATIO_OFFSET;
+
+	return parent_rate / cpu_clkdiv_ratio;
+}
+
+static int ap_cpu_clk_set_rate(struct clk_hw *hw, unsigned long rate,
+			       unsigned long parent_rate)
+{
+	struct ap_cpu_clk *clk = to_ap_cpu_clk(hw);
+	int ret, reg, divider = parent_rate / rate;
+	unsigned int cpu_clkdiv_reg, cpu_force_reg, cpu_ratio_reg, stable_bit;
+
+	cpu_clkdiv_reg = AP806_CA72MP2_0_PLL_CR_0_REG_OFFSET +
+		(clk->cluster * AP806_CA72MP2_0_PLL_CR_CLUSTER_OFFSET);
+	cpu_force_reg = AP806_CA72MP2_0_PLL_CR_1_REG_OFFSET +
+		(clk->cluster * AP806_CA72MP2_0_PLL_CR_CLUSTER_OFFSET);
+	cpu_ratio_reg = AP806_CA72MP2_0_PLL_CR_2_REG_OFFSET +
+		(clk->cluster * AP806_CA72MP2_0_PLL_CR_CLUSTER_OFFSET);
+
+	regmap_update_bits(clk->pll_cr_base, cpu_clkdiv_reg,
+			   AP806_PLL_CR_0_CPU_CLK_DIV_RATIO_MASK, divider);
+
+	regmap_update_bits(clk->pll_cr_base, cpu_force_reg,
+			   AP806_PLL_CR_0_CPU_CLK_RELOAD_FORCE_MASK,
+			   AP806_PLL_CR_0_CPU_CLK_RELOAD_FORCE_MASK);
+
+	regmap_update_bits(clk->pll_cr_base, cpu_ratio_reg,
+			   BIT(AP806_PLL_CR_0_CPU_CLK_RELOAD_RATIO_OFFSET),
+			   BIT(AP806_PLL_CR_0_CPU_CLK_RELOAD_RATIO_OFFSET));
+
+	stable_bit = BIT(clk->cluster * AP806_CA72MP2_0_PLL_RATIO_STATE),
+
+	ret = regmap_read_poll_timeout(clk->pll_cr_base,
+				       AP806_CA72MP2_0_PLL_SR_REG_OFFSET, reg,
+				       reg & stable_bit, STATUS_POLL_PERIOD_US,
+				       STATUS_POLL_TIMEOUT_US);
+	if (ret)
+		return ret;
+
+	regmap_update_bits(clk->pll_cr_base, cpu_ratio_reg,
+			   BIT(AP806_PLL_CR_0_CPU_CLK_RELOAD_RATIO_OFFSET), 0);
+
+	return 0;
+}
+
+static long ap_cpu_clk_round_rate(struct clk_hw *hw, unsigned long rate,
+				  unsigned long *parent_rate)
+{
+	int divider = *parent_rate / rate;
+
+	divider = min(divider, APN806_MAX_DIVIDER);
+
+	return *parent_rate / divider;
+}
+
+static const struct clk_ops ap_cpu_clk_ops = {
+	.recalc_rate	= ap_cpu_clk_recalc_rate,
+	.round_rate	= ap_cpu_clk_round_rate,
+	.set_rate	= ap_cpu_clk_set_rate,
+};
+
+static int ap_cpu_clock_probe(struct platform_device *pdev)
+{
+	int ret, nclusters = 0, cluster_index = 0;
+	struct device *dev = &pdev->dev;
+	struct device_node *dn, *np = dev->of_node;
+	struct clk_hw_onecell_data *ap_cpu_data;
+	struct ap_cpu_clk *ap_cpu_clk;
+	struct regmap *regmap;
+
+	regmap = syscon_node_to_regmap(np->parent);
+	if (IS_ERR(regmap)) {
+		pr_err("cannot get pll_cr_base regmap\n");
+		return PTR_ERR(regmap);
+	}
+
+	/*
+	 * AP806 has 4 cpus and DFS for AP806 is controlled per
+	 * cluster (2 CPUs per cluster), cpu0 and cpu1 are fixed to
+	 * cluster0 while cpu2 and cpu3 are fixed to cluster1 whether
+	 * they are enabled or not.  Since cpu0 is the boot cpu, then
+	 * cluster0 must exist.  If cpu2 or cpu3 is enabled, cluster1
+	 * will exist and the cluster number is 2; otherwise the
+	 * cluster number is 1.
+	 */
+	nclusters = 1;
+	for_each_of_cpu_node(dn) {
+		int cpu, err;
+
+		err = of_property_read_u32(dn, "reg", &cpu);
+		if (WARN_ON(err))
+			return err;
+
+		/* If cpu2 or cpu3 is enabled */
+		if (cpu & APN806_CLUSTER_NUM_MASK) {
+			nclusters = 2;
+			break;
+		}
+	}
+	/*
+	 * DFS for AP806 is controlled per cluster (2 CPUs per cluster),
+	 * so allocate structs per cluster
+	 */
+	ap_cpu_clk = devm_kcalloc(dev, nclusters, sizeof(*ap_cpu_clk),
+				  GFP_KERNEL);
+	if (!ap_cpu_clk)
+		return -ENOMEM;
+
+	ap_cpu_data = devm_kzalloc(dev, sizeof(*ap_cpu_data) +
+				sizeof(struct clk_hw *) * nclusters,
+				GFP_KERNEL);
+	if (!ap_cpu_data)
+		return -ENOMEM;
+
+	for_each_of_cpu_node(dn) {
+		char *clk_name = "cpu-cluster-0";
+		struct clk_init_data init;
+		const char *parent_name;
+		struct clk *parent;
+		int cpu, err;
+
+		err = of_property_read_u32(dn, "reg", &cpu);
+		if (WARN_ON(err))
+			return err;
+
+		cluster_index = cpu & APN806_CLUSTER_NUM_MASK;
+		cluster_index >>= APN806_CLUSTER_NUM_OFFSET;
+
+		/* Initialize once for one cluster */
+		if (ap_cpu_data->hws[cluster_index])
+			continue;
+
+		parent = of_clk_get(np, cluster_index);
+		if (IS_ERR(parent)) {
+			dev_err(dev, "Could not get the clock parent\n");
+			return -EINVAL;
+		}
+		parent_name =  __clk_get_name(parent);
+		clk_name[12] += cluster_index;
+		ap_cpu_clk[cluster_index].clk_name =
+			ap_cp_unique_name(dev, np->parent, clk_name);
+		ap_cpu_clk[cluster_index].cluster = cluster_index;
+		ap_cpu_clk[cluster_index].pll_cr_base = regmap;
+		ap_cpu_clk[cluster_index].hw.init = &init;
+		ap_cpu_clk[cluster_index].dev = dev;
+
+		init.name = ap_cpu_clk[cluster_index].clk_name;
+		init.ops = &ap_cpu_clk_ops;
+		init.num_parents = 1;
+		init.parent_names = &parent_name;
+
+		ret = devm_clk_hw_register(dev, &ap_cpu_clk[cluster_index].hw);
+		if (ret)
+			return ret;
+		ap_cpu_data->hws[cluster_index] = &ap_cpu_clk[cluster_index].hw;
+	}
+
+	ap_cpu_data->num = cluster_index + 1;
+
+	ret = of_clk_add_hw_provider(np, of_clk_hw_onecell_get, ap_cpu_data);
+	if (ret)
+		dev_err(dev, "failed to register OF clock provider\n");
+
+	return ret;
+}
+
+static const struct of_device_id ap_cpu_clock_of_match[] = {
+	{ .compatible = "marvell,ap806-cpu-clock", },
+	{ }
+};
+
+static struct platform_driver ap_cpu_clock_driver = {
+	.probe = ap_cpu_clock_probe,
+	.driver		= {
+		.name	= "marvell-ap-cpu-clock",
+		.of_match_table = ap_cpu_clock_of_match,
+		.suppress_bind_attrs = true,
+	},
+};
+builtin_platform_driver(ap_cpu_clock_driver);