clk: mvebu: add mvebu core clocks.

This driver allows to provide DT clocks for core clocks found on
Marvell Kirkwood, Dove & 370/XP SoCs. The core clock frequencies and
ratios are determined by decoding the Sample-At-Reset registers.

Although technically correct, using a divider of 0 will lead to
div_by_zero panic. Let's use a ratio of 0/1 instead to fail later
with a zero clock.
Signed-off-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: NSebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: NAndrew Lunn <andrew@lunn.ch>
Tested-by Gregory CLEMENT <gregory.clement@free-electrons.com>

Documentation/devicetree/bindings/clock/mvebu-core-clock.txt

+* Core Clock bindings for Marvell MVEBU SoCs
+
+Marvell MVEBU SoCs usually allow to determine core clock frequencies by
+reading the Sample-At-Reset (SAR) register. The core clock consumer should
+specify the desired clock by having the clock ID in its "clocks" phandle cell.
+
+The following is a list of provided IDs and clock names on Armada 370/XP:
+ 0 = tclk    (Internal Bus clock)
+ 1 = cpuclk  (CPU clock)
+ 2 = nbclk   (L2 Cache clock)
+ 3 = hclk    (DRAM control clock)
+ 4 = dramclk (DDR clock)
+
+The following is a list of provided IDs and clock names on Kirkwood and Dove:
+ 0 = tclk   (Internal Bus clock)
+ 1 = cpuclk (CPU0 clock)
+ 2 = l2clk  (L2 Cache clock derived from CPU0 clock)
+ 3 = ddrclk (DDR controller clock derived from CPU0 clock)
+
+Required properties:
+- compatible : shall be one of the following:
+	"marvell,armada-370-core-clock" - For Armada 370 SoC core clocks
+	"marvell,armada-xp-core-clock" - For Armada XP SoC core clocks
+	"marvell,dove-core-clock" - for Dove SoC core clocks
+	"marvell,kirkwood-core-clock" - for Kirkwood SoC (except mv88f6180)
+	"marvell,mv88f6180-core-clock" - for Kirkwood MV88f6180 SoC
+- reg : shall be the register address of the Sample-At-Reset (SAR) register
+- #clock-cells : from common clock binding; shall be set to 1
+
+Optional properties:
+- clock-output-names : from common clock binding; allows overwrite default clock
+	output names ("tclk", "cpuclk", "l2clk", "ddrclk")
+
+Example:
+
+core_clk: core-clocks@d0214 {
+	compatible = "marvell,dove-core-clock";
+	reg = <0xd0214 0x4>;
+	#clock-cells = <1>;
+};
+
+spi0: spi@10600 {
+	compatible = "marvell,orion-spi";
+	/* ... */
+	/* get tclk from core clock provider */
+	clocks = <&core_clk 0>;
+};

drivers/clk/Kconfig

@@ -54,3 +54,5 @@ config COMMON_CLK_MAX77686
 	  This driver supports Maxim 77686 crystal oscillator clock. 
 
 endmenu
+
+source "drivers/clk/mvebu/Kconfig"

drivers/clk/Makefile

@@ -13,6 +13,7 @@ obj-$(CONFIG_PLAT_SPEAR)	+= spear/
 obj-$(CONFIG_ARCH_U300)		+= clk-u300.o
 obj-$(CONFIG_COMMON_CLK_VERSATILE) += versatile/
 obj-$(CONFIG_ARCH_PRIMA2)	+= clk-prima2.o
+obj-$(CONFIG_PLAT_ORION)	+= mvebu/
 ifeq ($(CONFIG_COMMON_CLK), y)
 obj-$(CONFIG_ARCH_MMP)		+= mmp/
 endif

drivers/clk/mvebu/Kconfig

+config MVEBU_CLK_CORE
+       bool
+

drivers/clk/mvebu/Makefile

+obj-$(CONFIG_MVEBU_CLK_CORE) 	+= clk.o clk-core.o

drivers/clk/mvebu/clk-core.c

+/*
+ * Marvell EBU clock core handling defined at reset
+ *
+ * Copyright (C) 2012 Marvell
+ *
+ * Gregory CLEMENT <gregory.clement@free-electrons.com>
+ * Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.  This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+#include <linux/kernel.h>
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/clk-provider.h>
+#include <linux/of_address.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include "clk-core.h"
+
+struct core_ratio {
+	int id;
+	const char *name;
+};
+
+struct core_clocks {
+	u32 (*get_tclk_freq)(void __iomem *sar);
+	u32 (*get_cpu_freq)(void __iomem *sar);
+	void (*get_clk_ratio)(void __iomem *sar, int id, int *mult, int *div);
+	const struct core_ratio *ratios;
+	int num_ratios;
+};
+
+static struct clk_onecell_data clk_data;
+
+static void __init mvebu_clk_core_setup(struct device_node *np,
+				 struct core_clocks *coreclk)
+{
+	const char *tclk_name = "tclk";
+	const char *cpuclk_name = "cpuclk";
+	void __iomem *base;
+	unsigned long rate;
+	int n;
+
+	base = of_iomap(np, 0);
+	if (WARN_ON(!base))
+		return;
+
+	/*
+	 * Allocate struct for TCLK, cpu clk, and core ratio clocks
+	 */
+	clk_data.clk_num = 2 + coreclk->num_ratios;
+	clk_data.clks = kzalloc(clk_data.clk_num * sizeof(struct clk *),
+				GFP_KERNEL);
+	if (WARN_ON(!clk_data.clks))
+		return;
+
+	/*
+	 * Register TCLK
+	 */
+	of_property_read_string_index(np, "clock-output-names", 0,
+				      &tclk_name);
+	rate = coreclk->get_tclk_freq(base);
+	clk_data.clks[0] = clk_register_fixed_rate(NULL, tclk_name, NULL,
+						   CLK_IS_ROOT, rate);
+	WARN_ON(IS_ERR(clk_data.clks[0]));
+
+	/*
+	 * Register CPU clock
+	 */
+	of_property_read_string_index(np, "clock-output-names", 1,
+				      &cpuclk_name);
+	rate = coreclk->get_cpu_freq(base);
+	clk_data.clks[1] = clk_register_fixed_rate(NULL, cpuclk_name, NULL,
+						   CLK_IS_ROOT, rate);
+	WARN_ON(IS_ERR(clk_data.clks[1]));
+
+	/*
+	 * Register fixed-factor clocks derived from CPU clock
+	 */
+	for (n = 0; n < coreclk->num_ratios; n++) {
+		const char *rclk_name = coreclk->ratios[n].name;
+		int mult, div;
+
+		of_property_read_string_index(np, "clock-output-names",
+					      2+n, &rclk_name);
+		coreclk->get_clk_ratio(base, coreclk->ratios[n].id,
+				       &mult, &div);
+		clk_data.clks[2+n] = clk_register_fixed_factor(NULL, rclk_name,
+				       cpuclk_name, 0, mult, div);
+		WARN_ON(IS_ERR(clk_data.clks[2+n]));
+	};
+
+	/*
+	 * SAR register isn't needed anymore
+	 */
+	iounmap(base);
+
+	of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data);
+}
+
+#ifdef CONFIG_MACH_ARMADA_370_XP
+/*
+ * Armada 370/XP Sample At Reset is a 64 bit bitfiled split in two
+ * register of 32 bits
+ */
+
+#define SARL				    0	/* Low part [0:31] */
+#define	    SARL_AXP_PCLK_FREQ_OPT	    21
+#define	    SARL_AXP_PCLK_FREQ_OPT_MASK	    0x7
+#define	    SARL_A370_PCLK_FREQ_OPT	    11
+#define	    SARL_A370_PCLK_FREQ_OPT_MASK    0xF
+#define	    SARL_AXP_FAB_FREQ_OPT	    24
+#define	    SARL_AXP_FAB_FREQ_OPT_MASK	    0xF
+#define	    SARL_A370_FAB_FREQ_OPT	    15
+#define	    SARL_A370_FAB_FREQ_OPT_MASK	    0x1F
+#define	    SARL_A370_TCLK_FREQ_OPT	    20
+#define	    SARL_A370_TCLK_FREQ_OPT_MASK    0x1
+#define SARH				    4	/* High part [32:63] */
+#define	    SARH_AXP_PCLK_FREQ_OPT	    (52-32)
+#define	    SARH_AXP_PCLK_FREQ_OPT_MASK	    0x1
+#define	    SARH_AXP_PCLK_FREQ_OPT_SHIFT    3
+#define	    SARH_AXP_FAB_FREQ_OPT	    (51-32)
+#define	    SARH_AXP_FAB_FREQ_OPT_MASK	    0x1
+#define	    SARH_AXP_FAB_FREQ_OPT_SHIFT	    4
+
+static const u32 __initconst armada_370_tclk_frequencies[] = {
+	16600000,
+	20000000,
+};
+
+static u32 __init armada_370_get_tclk_freq(void __iomem *sar)
+{
+	u8 tclk_freq_select = 0;
+
+	tclk_freq_select = ((readl(sar) >> SARL_A370_TCLK_FREQ_OPT) &
+			    SARL_A370_TCLK_FREQ_OPT_MASK);
+	return armada_370_tclk_frequencies[tclk_freq_select];
+}
+
+static const u32 __initconst armada_370_cpu_frequencies[] = {
+	400000000,
+	533000000,
+	667000000,
+	800000000,
+	1000000000,
+	1067000000,
+	1200000000,
+};
+
+static u32 __init armada_370_get_cpu_freq(void __iomem *sar)
+{
+	u32 cpu_freq;
+	u8 cpu_freq_select = 0;
+
+	cpu_freq_select = ((readl(sar) >> SARL_A370_PCLK_FREQ_OPT) &
+			   SARL_A370_PCLK_FREQ_OPT_MASK);
+	if (cpu_freq_select > ARRAY_SIZE(armada_370_cpu_frequencies)) {
+		pr_err("CPU freq select unsuported %d\n", cpu_freq_select);
+		cpu_freq = 0;
+	} else
+		cpu_freq = armada_370_cpu_frequencies[cpu_freq_select];
+
+	return cpu_freq;
+}
+
+enum { A370_XP_NBCLK, A370_XP_HCLK, A370_XP_DRAMCLK };
+
+static const struct core_ratio __initconst armada_370_xp_core_ratios[] = {
+	{ .id = A370_XP_NBCLK,	 .name = "nbclk" },
+	{ .id = A370_XP_HCLK,	 .name = "hclk" },
+	{ .id = A370_XP_DRAMCLK, .name = "dramclk" },
+};
+
+static const int __initconst armada_370_xp_nbclk_ratios[32][2] = {
+	{0, 1}, {1, 2}, {2, 2}, {2, 2},
+	{1, 2}, {1, 2}, {1, 1}, {2, 3},
+	{0, 1}, {1, 2}, {2, 4}, {0, 1},
+	{1, 2}, {0, 1}, {0, 1}, {2, 2},
+	{0, 1}, {0, 1}, {0, 1}, {1, 1},
+	{2, 3}, {0, 1}, {0, 1}, {0, 1},
+	{0, 1}, {0, 1}, {0, 1}, {1, 1},
+	{0, 1}, {0, 1}, {0, 1}, {0, 1},
+};
+
+static const int __initconst armada_370_xp_hclk_ratios[32][2] = {
+	{0, 1}, {1, 2}, {2, 6}, {2, 3},
+	{1, 3}, {1, 4}, {1, 2}, {2, 6},
+	{0, 1}, {1, 6}, {2, 10}, {0, 1},
+	{1, 4}, {0, 1}, {0, 1}, {2, 5},
+	{0, 1}, {0, 1}, {0, 1}, {1, 2},
+	{2, 6}, {0, 1}, {0, 1}, {0, 1},
+	{0, 1}, {0, 1}, {0, 1}, {1, 1},
+	{0, 1}, {0, 1}, {0, 1}, {0, 1},
+};
+
+static const int __initconst armada_370_xp_dramclk_ratios[32][2] = {
+	{0, 1}, {1, 2}, {2, 3}, {2, 3},
+	{1, 3}, {1, 2}, {1, 2}, {2, 6},
+	{0, 1}, {1, 3}, {2, 5}, {0, 1},
+	{1, 4}, {0, 1}, {0, 1}, {2, 5},
+	{0, 1}, {0, 1}, {0, 1}, {1, 1},
+	{2, 3}, {0, 1}, {0, 1}, {0, 1},
+	{0, 1}, {0, 1}, {0, 1}, {1, 1},
+	{0, 1}, {0, 1}, {0, 1}, {0, 1},
+};
+
+static void __init armada_370_xp_get_clk_ratio(u32 opt,
+	void __iomem *sar, int id, int *mult, int *div)
+{
+	switch (id) {
+	case A370_XP_NBCLK:
+		*mult = armada_370_xp_nbclk_ratios[opt][0];
+		*div = armada_370_xp_nbclk_ratios[opt][1];
+		break;
+	case A370_XP_HCLK:
+		*mult = armada_370_xp_hclk_ratios[opt][0];
+		*div = armada_370_xp_hclk_ratios[opt][1];
+		break;
+	case A370_XP_DRAMCLK:
+		*mult = armada_370_xp_dramclk_ratios[opt][0];
+		*div = armada_370_xp_dramclk_ratios[opt][1];
+		break;
+	}
+}
+
+static void __init armada_370_get_clk_ratio(
+	void __iomem *sar, int id, int *mult, int *div)
+{
+	u32 opt = ((readl(sar) >> SARL_A370_FAB_FREQ_OPT) &
+		SARL_A370_FAB_FREQ_OPT_MASK);
+
+	armada_370_xp_get_clk_ratio(opt, sar, id, mult, div);
+}
+
+
+static const struct core_clocks armada_370_core_clocks = {
+	.get_tclk_freq = armada_370_get_tclk_freq,
+	.get_cpu_freq = armada_370_get_cpu_freq,
+	.get_clk_ratio = armada_370_get_clk_ratio,
+	.ratios = armada_370_xp_core_ratios,
+	.num_ratios = ARRAY_SIZE(armada_370_xp_core_ratios),
+};
+
+static const u32 __initconst armada_xp_cpu_frequencies[] = {
+	1000000000,
+	1066000000,
+	1200000000,
+	1333000000,
+	1500000000,
+	1666000000,
+	1800000000,
+	2000000000,
+	667000000,
+	0,
+	800000000,
+	1600000000,
+};
+
+/* For Armada XP TCLK frequency is fix: 250MHz */
+static u32 __init armada_xp_get_tclk_freq(void __iomem *sar)
+{
+	return 250 * 1000 * 1000;
+}
+
+static u32 __init armada_xp_get_cpu_freq(void __iomem *sar)
+{
+	u32 cpu_freq;
+	u8 cpu_freq_select = 0;
+
+	cpu_freq_select = ((readl(sar) >> SARL_AXP_PCLK_FREQ_OPT) &
+			   SARL_AXP_PCLK_FREQ_OPT_MASK);
+	/*
+	 * The upper bit is not contiguous to the other ones and
+	 * located in the high part of the SAR registers
+	 */
+	cpu_freq_select |= (((readl(sar+4) >> SARH_AXP_PCLK_FREQ_OPT) &
+			     SARH_AXP_PCLK_FREQ_OPT_MASK)
+			    << SARH_AXP_PCLK_FREQ_OPT_SHIFT);
+	if (cpu_freq_select > ARRAY_SIZE(armada_xp_cpu_frequencies)) {
+		pr_err("CPU freq select unsuported: %d\n", cpu_freq_select);
+		cpu_freq = 0;
+	} else
+		cpu_freq = armada_xp_cpu_frequencies[cpu_freq_select];
+
+	return cpu_freq;
+}
+
+static void __init armada_xp_get_clk_ratio(
+	void __iomem *sar, int id, int *mult, int *div)
+{
+
+	u32 opt = ((readl(sar) >> SARL_AXP_FAB_FREQ_OPT) &
+	      SARL_AXP_FAB_FREQ_OPT_MASK);
+	/*
+	 * The upper bit is not contiguous to the other ones and
+	 * located in the high part of the SAR registers
+	 */
+	opt |= (((readl(sar+4) >> SARH_AXP_FAB_FREQ_OPT) &
+		SARH_AXP_FAB_FREQ_OPT_MASK)
+	       << SARH_AXP_FAB_FREQ_OPT_SHIFT);
+
+	armada_370_xp_get_clk_ratio(opt, sar, id, mult, div);
+}
+
+static const struct core_clocks armada_xp_core_clocks = {
+	.get_tclk_freq = armada_xp_get_tclk_freq,
+	.get_cpu_freq = armada_xp_get_cpu_freq,
+	.get_clk_ratio = armada_xp_get_clk_ratio,
+	.ratios = armada_370_xp_core_ratios,
+	.num_ratios = ARRAY_SIZE(armada_370_xp_core_ratios),
+};
+
+#endif /* CONFIG_MACH_ARMADA_370_XP */
+
+/*
+ * Dove PLL sample-at-reset configuration
+ *
+ * SAR0[8:5]   : CPU frequency
+ *		 5  = 1000 MHz
+ *		 6  =  933 MHz
+ *		 7  =  933 MHz
+ *		 8  =  800 MHz
+ *		 9  =  800 MHz
+ *		 10 =  800 MHz
+ *		 11 = 1067 MHz
+ *		 12 =  667 MHz
+ *		 13 =  533 MHz
+ *		 14 =  400 MHz
+ *		 15 =  333 MHz
+ *		 others reserved.
+ *
+ * SAR0[11:9]  : CPU to L2 Clock divider ratio
+ *		 0 = (1/1) * CPU
+ *		 2 = (1/2) * CPU
+ *		 4 = (1/3) * CPU
+ *		 6 = (1/4) * CPU
+ *		 others reserved.
+ *
+ * SAR0[15:12] : CPU to DDR DRAM Clock divider ratio
+ *		 0  = (1/1) * CPU
+ *		 2  = (1/2) * CPU
+ *		 3  = (2/5) * CPU
+ *		 4  = (1/3) * CPU
+ *		 6  = (1/4) * CPU
+ *		 8  = (1/5) * CPU
+ *		 10 = (1/6) * CPU
+ *		 12 = (1/7) * CPU
+ *		 14 = (1/8) * CPU
+ *		 15 = (1/10) * CPU
+ *		 others reserved.
+ *
+ * SAR0[24:23] : TCLK frequency
+ *		 0 = 166 MHz
+ *		 1 = 125 MHz
+ *		 others reserved.
+ */
+#ifdef CONFIG_ARCH_DOVE
+#define SAR_DOVE_CPU_FREQ		5
+#define SAR_DOVE_CPU_FREQ_MASK		0xf
+#define SAR_DOVE_L2_RATIO		9
+#define SAR_DOVE_L2_RATIO_MASK		0x7
+#define SAR_DOVE_DDR_RATIO		12
+#define SAR_DOVE_DDR_RATIO_MASK		0xf
+#define SAR_DOVE_TCLK_FREQ		23
+#define SAR_DOVE_TCLK_FREQ_MASK		0x3
+
+static const u32 __initconst dove_tclk_frequencies[] = {
+	166666667,
+	125000000,
+	0, 0
+};
+
+static u32 __init dove_get_tclk_freq(void __iomem *sar)
+{
+	u32 opt = (readl(sar) >> SAR_DOVE_TCLK_FREQ) &
+		SAR_DOVE_TCLK_FREQ_MASK;
+	return dove_tclk_frequencies[opt];
+}
+
+static const u32 __initconst dove_cpu_frequencies[] = {
+	0, 0, 0, 0, 0,
+	1000000000,
+	933333333, 933333333,
+	800000000, 800000000, 800000000,
+	1066666667,
+	666666667,
+	533333333,
+	400000000,
+	333333333
+};
+
+static u32 __init dove_get_cpu_freq(void __iomem *sar)
+{
+	u32 opt = (readl(sar) >> SAR_DOVE_CPU_FREQ) &
+		SAR_DOVE_CPU_FREQ_MASK;
+	return dove_cpu_frequencies[opt];
+}
+
+enum { DOVE_CPU_TO_L2, DOVE_CPU_TO_DDR };
+
+static const struct core_ratio __initconst dove_core_ratios[] = {
+	{ .id = DOVE_CPU_TO_L2, .name = "l2clk", },
+	{ .id = DOVE_CPU_TO_DDR, .name = "ddrclk", }
+};
+
+static const int __initconst dove_cpu_l2_ratios[8][2] = {
+	{ 1, 1 }, { 0, 1 }, { 1, 2 }, { 0, 1 },
+	{ 1, 3 }, { 0, 1 }, { 1, 4 }, { 0, 1 }
+};
+
+static const int __initconst dove_cpu_ddr_ratios[16][2] = {
+	{ 1, 1 }, { 0, 1 }, { 1, 2 }, { 2, 5 },
+	{ 1, 3 }, { 0, 1 }, { 1, 4 }, { 0, 1 },
+	{ 1, 5 }, { 0, 1 }, { 1, 6 }, { 0, 1 },
+	{ 1, 7 }, { 0, 1 }, { 1, 8 }, { 1, 10 }
+};
+
+static void __init dove_get_clk_ratio(
+	void __iomem *sar, int id, int *mult, int *div)
+{
+	switch (id) {
+	case DOVE_CPU_TO_L2:
+	{
+		u32 opt = (readl(sar) >> SAR_DOVE_L2_RATIO) &
+			SAR_DOVE_L2_RATIO_MASK;
+		*mult = dove_cpu_l2_ratios[opt][0];
+		*div = dove_cpu_l2_ratios[opt][1];
+		break;
+	}
+	case DOVE_CPU_TO_DDR:
+	{
+		u32 opt = (readl(sar) >> SAR_DOVE_DDR_RATIO) &
+			SAR_DOVE_DDR_RATIO_MASK;
+		*mult = dove_cpu_ddr_ratios[opt][0];
+		*div = dove_cpu_ddr_ratios[opt][1];
+		break;
+	}
+	}
+}
+
+static const struct core_clocks dove_core_clocks = {
+	.get_tclk_freq = dove_get_tclk_freq,
+	.get_cpu_freq = dove_get_cpu_freq,
+	.get_clk_ratio = dove_get_clk_ratio,
+	.ratios = dove_core_ratios,
+	.num_ratios = ARRAY_SIZE(dove_core_ratios),
+};
+#endif /* CONFIG_ARCH_DOVE */
+
+/*
+ * Kirkwood PLL sample-at-reset configuration
+ * (6180 has different SAR layout than other Kirkwood SoCs)
+ *
+ * SAR0[4:3,22,1] : CPU frequency (6281,6292,6282)
+ *	4  =  600 MHz
+ *	6  =  800 MHz
+ *	7  = 1000 MHz
+ *	9  = 1200 MHz
+ *	12 = 1500 MHz
+ *	13 = 1600 MHz
+ *	14 = 1800 MHz
+ *	15 = 2000 MHz
+ *	others reserved.
+ *
+ * SAR0[19,10:9] : CPU to L2 Clock divider ratio (6281,6292,6282)
+ *	1 = (1/2) * CPU
+ *	3 = (1/3) * CPU
+ *	5 = (1/4) * CPU
+ *	others reserved.
+ *
+ * SAR0[8:5] : CPU to DDR DRAM Clock divider ratio (6281,6292,6282)
+ *	2 = (1/2) * CPU
+ *	4 = (1/3) * CPU
+ *	6 = (1/4) * CPU
+ *	7 = (2/9) * CPU
+ *	8 = (1/5) * CPU
+ *	9 = (1/6) * CPU
+ *	others reserved.
+ *
+ * SAR0[4:2] : Kirkwood 6180 cpu/l2/ddr clock configuration (6180 only)
+ *	5 = [CPU =  600 MHz, L2 = (1/2) * CPU, DDR = 200 MHz = (1/3) * CPU]
+ *	6 = [CPU =  800 MHz, L2 = (1/2) * CPU, DDR = 200 MHz = (1/4) * CPU]
+ *	7 = [CPU = 1000 MHz, L2 = (1/2) * CPU, DDR = 200 MHz = (1/5) * CPU]
+ *	others reserved.
+ *
+ * SAR0[21] : TCLK frequency
+ *	0 = 200 MHz
+ *	1 = 166 MHz
+ *	others reserved.
+ */
+#ifdef CONFIG_ARCH_KIRKWOOD
+#define SAR_KIRKWOOD_CPU_FREQ(x)	\
+	(((x & (1 <<  1)) >>  1) |	\
+	 ((x & (1 << 22)) >> 21) |	\
+	 ((x & (3 <<  3)) >>  1))
+#define SAR_KIRKWOOD_L2_RATIO(x)	\
+	(((x & (3 <<  9)) >> 9) |	\
+	 (((x & (1 << 19)) >> 17)))
+#define SAR_KIRKWOOD_DDR_RATIO		5
+#define SAR_KIRKWOOD_DDR_RATIO_MASK	0xf
+#define SAR_MV88F6180_CLK		2
+#define SAR_MV88F6180_CLK_MASK		0x7
+#define SAR_KIRKWOOD_TCLK_FREQ		21
+#define SAR_KIRKWOOD_TCLK_FREQ_MASK	0x1
+
+enum { KIRKWOOD_CPU_TO_L2, KIRKWOOD_CPU_TO_DDR };
+
+static const struct core_ratio __initconst kirkwood_core_ratios[] = {
+	{ .id = KIRKWOOD_CPU_TO_L2, .name = "l2clk", },
+	{ .id = KIRKWOOD_CPU_TO_DDR, .name = "ddrclk", }
+};
+
+static u32 __init kirkwood_get_tclk_freq(void __iomem *sar)
+{
+	u32 opt = (readl(sar) >> SAR_KIRKWOOD_TCLK_FREQ) &
+		SAR_KIRKWOOD_TCLK_FREQ_MASK;
+	return (opt) ? 166666667 : 200000000;
+}
+
+static const u32 __initconst kirkwood_cpu_frequencies[] = {
+	0, 0, 0, 0,
+	600000000,
+	0,
+	800000000,
+	1000000000,
+	0,
+	1200000000,
+	0, 0,
+	1500000000,
+	1600000000,
+	1800000000,
+	2000000000
+};
+
+static u32 __init kirkwood_get_cpu_freq(void __iomem *sar)
+{
+	u32 opt = SAR_KIRKWOOD_CPU_FREQ(readl(sar));
+	return kirkwood_cpu_frequencies[opt];
+}
+
+static const int __initconst kirkwood_cpu_l2_ratios[8][2] = {
+	{ 0, 1 }, { 1, 2 }, { 0, 1 }, { 1, 3 },
+	{ 0, 1 }, { 1, 4 }, { 0, 1 }, { 0, 1 }
+};
+
+static const int __initconst kirkwood_cpu_ddr_ratios[16][2] = {
+	{ 0, 1 }, { 0, 1 }, { 1, 2 }, { 0, 1 },
+	{ 1, 3 }, { 0, 1 }, { 1, 4 }, { 2, 9 },
+	{ 1, 5 }, { 1, 6 }, { 0, 1 }, { 0, 1 },
+	{ 0, 1 }, { 0, 1 }, { 0, 1 }, { 0, 1 }
+};
+
+static void __init kirkwood_get_clk_ratio(
+	void __iomem *sar, int id, int *mult, int *div)
+{
+	switch (id) {
+	case KIRKWOOD_CPU_TO_L2:
+	{
+		u32 opt = SAR_KIRKWOOD_L2_RATIO(readl(sar));
+		*mult = kirkwood_cpu_l2_ratios[opt][0];
+		*div = kirkwood_cpu_l2_ratios[opt][1];
+		break;
+	}
+	case KIRKWOOD_CPU_TO_DDR:
+	{
+		u32 opt = (readl(sar) >> SAR_KIRKWOOD_DDR_RATIO) &
+			SAR_KIRKWOOD_DDR_RATIO_MASK;
+		*mult = kirkwood_cpu_ddr_ratios[opt][0];
+		*div = kirkwood_cpu_ddr_ratios[opt][1];
+		break;
+	}
+	}
+}
+
+static const struct core_clocks kirkwood_core_clocks = {
+	.get_tclk_freq = kirkwood_get_tclk_freq,
+	.get_cpu_freq = kirkwood_get_cpu_freq,
+	.get_clk_ratio = kirkwood_get_clk_ratio,
+	.ratios = kirkwood_core_ratios,
+	.num_ratios = ARRAY_SIZE(kirkwood_core_ratios),
+};
+
+static const u32 __initconst mv88f6180_cpu_frequencies[] = {
+	0, 0, 0, 0, 0,
+	600000000,
+	800000000,
+	1000000000
+};
+
+static u32 __init mv88f6180_get_cpu_freq(void __iomem *sar)
+{
+	u32 opt = (readl(sar) >> SAR_MV88F6180_CLK) & SAR_MV88F6180_CLK_MASK;
+	return mv88f6180_cpu_frequencies[opt];
+}
+
+static const int __initconst mv88f6180_cpu_ddr_ratios[8][2] = {
+	{ 0, 1 }, { 0, 1 }, { 0, 1 }, { 0, 1 },
+	{ 0, 1 }, { 1, 3 }, { 1, 4 }, { 1, 5 }
+};
+
+static void __init mv88f6180_get_clk_ratio(
+	void __iomem *sar, int id, int *mult, int *div)
+{
+	switch (id) {
+	case KIRKWOOD_CPU_TO_L2:
+	{
+		/* mv88f6180 has a fixed 1:2 CPU-to-L2 ratio */
+		*mult = 1;
+		*div = 2;
+		break;
+	}
+	case KIRKWOOD_CPU_TO_DDR:
+	{
+		u32 opt = (readl(sar) >> SAR_MV88F6180_CLK) &
+			SAR_MV88F6180_CLK_MASK;
+		*mult = mv88f6180_cpu_ddr_ratios[opt][0];
+		*div = mv88f6180_cpu_ddr_ratios[opt][1];
+		break;
+	}
+	}
+}
+
+static const struct core_clocks mv88f6180_core_clocks = {
+	.get_tclk_freq = kirkwood_get_tclk_freq,
+	.get_cpu_freq = mv88f6180_get_cpu_freq,
+	.get_clk_ratio = mv88f6180_get_clk_ratio,
+	.ratios = kirkwood_core_ratios,
+	.num_ratios = ARRAY_SIZE(kirkwood_core_ratios),
+};
+#endif /* CONFIG_ARCH_KIRKWOOD */
+
+static const __initdata struct of_device_id clk_core_match[] = {
+#ifdef CONFIG_MACH_ARMADA_370_XP
+	{
+		.compatible = "marvell,armada-370-core-clock",
+		.data = &armada_370_core_clocks,
+	},
+	{
+		.compatible = "marvell,armada-xp-core-clock",
+		.data = &armada_xp_core_clocks,
+	},
+#endif
+#ifdef CONFIG_ARCH_DOVE
+	{
+		.compatible = "marvell,dove-core-clock",
+		.data = &dove_core_clocks,
+	},
+#endif
+
+#ifdef CONFIG_ARCH_KIRKWOOD
+	{
+		.compatible = "marvell,kirkwood-core-clock",
+		.data = &kirkwood_core_clocks,
+	},
+	{
+		.compatible = "marvell,mv88f6180-core-clock",
+		.data = &mv88f6180_core_clocks,
+	},
+#endif
+
+	{ }
+};
+
+void __init mvebu_core_clk_init(void)
+{
+	struct device_node *np;
+
+	for_each_matching_node(np, clk_core_match) {
+		const struct of_device_id *match =
+			of_match_node(clk_core_match, np);
+		mvebu_clk_core_setup(np, (struct core_clocks *)match->data);
+	}
+}

drivers/clk/mvebu/clk-core.h

+/*
+ *  * Marvell EBU clock core handling defined at reset
+ *
+ * Copyright (C) 2012 Marvell
+ *
+ * Gregory CLEMENT <gregory.clement@free-electrons.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.  This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#ifndef __MVEBU_CLK_CORE_H
+#define __MVEBU_CLK_CORE_H
+
+void __init mvebu_core_clk_init(void);
+
+#endif

drivers/clk/mvebu/clk.c

+/*
+ * Marvell EBU SoC clock handling.
+ *
+ * Copyright (C) 2012 Marvell
+ *
+ * Gregory CLEMENT <gregory.clement@free-electrons.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.  This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+#include <linux/kernel.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/of_address.h>
+#include <linux/clk/mvebu.h>
+#include <linux/of.h>
+#include "clk-core.h"
+
+void __init mvebu_clocks_init(void)
+{
+	mvebu_core_clk_init();
+}

include/linux/clk/mvebu.h

+/*
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef __CLK_MVEBU_H_
+#define __CLK_MVEBU_H_
+
+void __init mvebu_clocks_init(void);
+
+#endif