1 files changed, 510 insertions, 0 deletions
diff --git a/arch/arm/mach-prima2/clock.c b/arch/arm/mach-prima2/clock.c
new file mode 100644
index 000000000000..aebad7e565cf
--- /dev/null
+++ b/arch/arm/mach-prima2/clock.c
@@ -0,0 +1,510 @@
+/*
+ * Clock tree for CSR SiRFprimaII
+ *
+ * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
+ *
+ * Licensed under GPLv2 or later.
+ */
+
+#include <linux/module.h>
+#include <linux/bitops.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/io.h>
+#include <linux/clkdev.h>
+#include <linux/clk.h>
+#include <linux/spinlock.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <asm/mach/map.h>
+#include <mach/map.h>
+
+#define SIRFSOC_CLKC_CLK_EN0    0x0000
+#define SIRFSOC_CLKC_CLK_EN1    0x0004
+#define SIRFSOC_CLKC_REF_CFG    0x0014
+#define SIRFSOC_CLKC_CPU_CFG    0x0018
+#define SIRFSOC_CLKC_MEM_CFG    0x001c
+#define SIRFSOC_CLKC_SYS_CFG    0x0020
+#define SIRFSOC_CLKC_IO_CFG     0x0024
+#define SIRFSOC_CLKC_DSP_CFG    0x0028
+#define SIRFSOC_CLKC_GFX_CFG    0x002c
+#define SIRFSOC_CLKC_MM_CFG     0x0030
+#define SIRFSOC_LKC_LCD_CFG     0x0034
+#define SIRFSOC_CLKC_MMC_CFG    0x0038
+#define SIRFSOC_CLKC_PLL1_CFG0  0x0040
+#define SIRFSOC_CLKC_PLL2_CFG0  0x0044
+#define SIRFSOC_CLKC_PLL3_CFG0  0x0048
+#define SIRFSOC_CLKC_PLL1_CFG1  0x004c
+#define SIRFSOC_CLKC_PLL2_CFG1  0x0050
+#define SIRFSOC_CLKC_PLL3_CFG1  0x0054
+#define SIRFSOC_CLKC_PLL1_CFG2  0x0058
+#define SIRFSOC_CLKC_PLL2_CFG2  0x005c
+#define SIRFSOC_CLKC_PLL3_CFG2  0x0060
+
+#define SIRFSOC_CLOCK_VA_BASE		SIRFSOC_VA(0x005000)
+
+#define KHZ     1000
+#define MHZ     (KHZ * KHZ)
+
+struct clk_ops {
+	unsigned long (*get_rate)(struct clk *clk);
+	long (*round_rate)(struct clk *clk, unsigned long rate);
+	int (*set_rate)(struct clk *clk, unsigned long rate);
+	int (*enable)(struct clk *clk);
+	int (*disable)(struct clk *clk);
+	struct clk *(*get_parent)(struct clk *clk);
+	int (*set_parent)(struct clk *clk, struct clk *parent);
+};
+
+struct clk {
+	struct clk *parent;     /* parent clk */
+	unsigned long rate;     /* clock rate in Hz */
+	signed char usage;      /* clock enable count */
+	signed char enable_bit; /* enable bit: 0 ~ 63 */
+	unsigned short regofs;  /* register offset */
+	struct clk_ops *ops;    /* clock operation */
+};
+
+static DEFINE_SPINLOCK(clocks_lock);
+
+static inline unsigned long clkc_readl(unsigned reg)
+{
+	return readl(SIRFSOC_CLOCK_VA_BASE + reg);
+}
+
+static inline void clkc_writel(u32 val, unsigned reg)
+{
+	writel(val, SIRFSOC_CLOCK_VA_BASE + reg);
+}
+
+/*
+ * osc_rtc - real time oscillator - 32.768KHz
+ * osc_sys - high speed oscillator - 26MHz
+ */
+
+static struct clk clk_rtc = {
+	.rate = 32768,
+};
+
+static struct clk clk_osc = {
+	.rate = 26 * MHZ,
+};
+
+/*
+ * std pll
+ */
+static unsigned long std_pll_get_rate(struct clk *clk)
+{
+	unsigned long fin = clk_get_rate(clk->parent);
+	u32 regcfg2 = clk->regofs + SIRFSOC_CLKC_PLL1_CFG2 -
+		SIRFSOC_CLKC_PLL1_CFG0;
+
+	if (clkc_readl(regcfg2) & BIT(2)) {
+		/* pll bypass mode */
+		clk->rate = fin;
+	} else {
+		/* fout = fin * nf / nr / od */
+		u32 cfg0 = clkc_readl(clk->regofs);
+		u32 nf = (cfg0 & (BIT(13) - 1)) + 1;
+		u32 nr = ((cfg0 >> 13) & (BIT(6) - 1)) + 1;
+		u32 od = ((cfg0 >> 19) & (BIT(4) - 1)) + 1;
+		WARN_ON(fin % MHZ);
+		clk->rate = fin / MHZ * nf / nr / od * MHZ;
+	}
+
+	return clk->rate;
+}
+
+static int std_pll_set_rate(struct clk *clk, unsigned long rate)
+{
+	unsigned long fin, nf, nr, od, reg;
+
+	/*
+	 * fout = fin * nf / (nr * od);
+	 * set od = 1, nr = fin/MHz, so fout = nf * MHz
+	 */
+
+	nf = rate / MHZ;
+	if (unlikely((rate % MHZ) || nf > BIT(13) || nf < 1))
+		return -EINVAL;
+
+	fin = clk_get_rate(clk->parent);
+	BUG_ON(fin < MHZ);
+
+	nr = fin / MHZ;
+	BUG_ON((fin % MHZ) || nr > BIT(6));
+
+	od = 1;
+
+	reg = (nf - 1) | ((nr - 1) << 13) | ((od - 1) << 19);
+	clkc_writel(reg, clk->regofs);
+
+	reg = clk->regofs + SIRFSOC_CLKC_PLL1_CFG1 - SIRFSOC_CLKC_PLL1_CFG0;
+	clkc_writel((nf >> 1) - 1, reg);
+
+	reg = clk->regofs + SIRFSOC_CLKC_PLL1_CFG2 - SIRFSOC_CLKC_PLL1_CFG0;
+	while (!(clkc_readl(reg) & BIT(6)))
+		cpu_relax();
+
+	clk->rate = 0; /* set to zero will force recalculation */
+	return 0;
+}
+
+static struct clk_ops std_pll_ops = {
+	.get_rate = std_pll_get_rate,
+	.set_rate = std_pll_set_rate,
+};
+
+static struct clk clk_pll1 = {
+	.parent = &clk_osc,
+	.regofs = SIRFSOC_CLKC_PLL1_CFG0,
+	.ops = &std_pll_ops,
+};
+
+static struct clk clk_pll2 = {
+	.parent = &clk_osc,
+	.regofs = SIRFSOC_CLKC_PLL2_CFG0,
+	.ops = &std_pll_ops,
+};
+
+static struct clk clk_pll3 = {
+	.parent = &clk_osc,
+	.regofs = SIRFSOC_CLKC_PLL3_CFG0,
+	.ops = &std_pll_ops,
+};
+
+/*
+ * clock domains - cpu, mem, sys/io
+ */
+
+static struct clk clk_mem;
+
+static struct clk *dmn_get_parent(struct clk *clk)
+{
+	struct clk *clks[] = {
+		&clk_osc, &clk_rtc, &clk_pll1, &clk_pll2, &clk_pll3
+	};
+	u32 cfg = clkc_readl(clk->regofs);
+	WARN_ON((cfg & (BIT(3) - 1)) > 4);
+	return clks[cfg & (BIT(3) - 1)];
+}
+
+static int dmn_set_parent(struct clk *clk, struct clk *parent)
+{
+	const struct clk *clks[] = {
+		&clk_osc, &clk_rtc, &clk_pll1, &clk_pll2, &clk_pll3
+	};
+	u32 cfg = clkc_readl(clk->regofs);
+	int i;
+	for (i = 0; i < ARRAY_SIZE(clks); i++) {
+		if (clks[i] == parent) {
+			cfg &= ~(BIT(3) - 1);
+			clkc_writel(cfg | i, clk->regofs);
+			/* BIT(3) - switching status: 1 - busy, 0 - done */
+			while (clkc_readl(clk->regofs) & BIT(3))
+				cpu_relax();
+			return 0;
+		}
+	}
+	return -EINVAL;
+}
+
+static unsigned long dmn_get_rate(struct clk *clk)
+{
+	unsigned long fin = clk_get_rate(clk->parent);
+	u32 cfg = clkc_readl(clk->regofs);
+	if (cfg & BIT(24)) {
+		/* fcd bypass mode */
+		clk->rate = fin;
+	} else {
+		/*
+		 * wait count: bit[19:16], hold count: bit[23:20]
+		 */
+		u32 wait = (cfg >> 16) & (BIT(4) - 1);
+		u32 hold = (cfg >> 20) & (BIT(4) - 1);
+
+		clk->rate = fin / (wait + hold + 2);
+	}
+
+	return clk->rate;
+}
+
+static int dmn_set_rate(struct clk *clk, unsigned long rate)
+{
+	unsigned long fin;
+	unsigned ratio, wait, hold, reg;
+	unsigned bits = (clk == &clk_mem) ? 3 : 4;
+
+	fin = clk_get_rate(clk->parent);
+	ratio = fin / rate;
+
+	if (unlikely(ratio < 2 || ratio > BIT(bits + 1)))
+		return -EINVAL;
+
+	WARN_ON(fin % rate);
+
+	wait = (ratio >> 1) - 1;
+	hold = ratio - wait - 2;
+
+	reg = clkc_readl(clk->regofs);
+	reg &= ~(((BIT(bits) - 1) << 16) | ((BIT(bits) - 1) << 20));
+	reg |= (wait << 16) | (hold << 20) | BIT(25);
+	clkc_writel(reg, clk->regofs);
+
+	/* waiting FCD been effective */
+	while (clkc_readl(clk->regofs) & BIT(25))
+		cpu_relax();
+
+	clk->rate = 0; /* set to zero will force recalculation */
+
+	return 0;
+}
+
+/*
+ * cpu clock has no FCD register in Prima2, can only change pll
+ */
+static int cpu_set_rate(struct clk *clk, unsigned long rate)
+{
+	int ret1, ret2;
+	struct clk *cur_parent, *tmp_parent;
+
+	cur_parent = dmn_get_parent(clk);
+	BUG_ON(cur_parent == NULL || cur_parent->usage > 1);
+
+	/* switch to tmp pll before setting parent clock's rate */
+	tmp_parent = cur_parent == &clk_pll1 ? &clk_pll2 : &clk_pll1;
+	ret1 = dmn_set_parent(clk, tmp_parent);
+	BUG_ON(ret1);
+
+	ret2 = clk_set_rate(cur_parent, rate);
+
+	ret1 = dmn_set_parent(clk, cur_parent);
+
+	clk->rate = 0; /* set to zero will force recalculation */
+
+	return ret2 ? ret2 : ret1;
+}
+
+static struct clk_ops cpu_ops = {
+	.get_parent = dmn_get_parent,
+	.set_parent = dmn_set_parent,
+	.set_rate = cpu_set_rate,
+};
+
+static struct clk clk_cpu = {
+	.parent = &clk_pll1,
+	.regofs = SIRFSOC_CLKC_CPU_CFG,
+	.ops = &cpu_ops,
+};
+
+
+static struct clk_ops msi_ops = {
+	.set_rate = dmn_set_rate,
+	.get_rate = dmn_get_rate,
+	.set_parent = dmn_set_parent,
+	.get_parent = dmn_get_parent,
+};
+
+static struct clk clk_mem = {
+	.parent = &clk_pll2,
+	.regofs = SIRFSOC_CLKC_MEM_CFG,
+	.ops = &msi_ops,
+};
+
+static struct clk clk_sys = {
+	.parent = &clk_pll3,
+	.regofs = SIRFSOC_CLKC_SYS_CFG,
+	.ops = &msi_ops,
+};
+
+static struct clk clk_io = {
+	.parent = &clk_pll3,
+	.regofs = SIRFSOC_CLKC_IO_CFG,
+	.ops = &msi_ops,
+};
+
+/*
+ * on-chip clock sets
+ */
+static struct clk_lookup onchip_clks[] = {
+	{
+		.dev_id = "rtc",
+		.clk = &clk_rtc,
+	}, {
+		.dev_id = "osc",
+		.clk = &clk_osc,
+	}, {
+		.dev_id = "pll1",
+		.clk = &clk_pll1,
+	}, {
+		.dev_id = "pll2",
+		.clk = &clk_pll2,
+	}, {
+		.dev_id = "pll3",
+		.clk = &clk_pll3,
+	}, {
+		.dev_id = "cpu",
+		.clk = &clk_cpu,
+	}, {
+		.dev_id = "mem",
+		.clk = &clk_mem,
+	}, {
+		.dev_id = "sys",
+		.clk = &clk_sys,
+	}, {
+		.dev_id = "io",
+		.clk = &clk_io,
+	},
+};
+
+int clk_enable(struct clk *clk)
+{
+	unsigned long flags;
+
+	if (unlikely(IS_ERR_OR_NULL(clk)))
+		return -EINVAL;
+
+	if (clk->parent)
+		clk_enable(clk->parent);
+
+	spin_lock_irqsave(&clocks_lock, flags);
+	if (!clk->usage++ && clk->ops && clk->ops->enable)
+		clk->ops->enable(clk);
+	spin_unlock_irqrestore(&clocks_lock, flags);
+	return 0;
+}
+EXPORT_SYMBOL(clk_enable);
+
+void clk_disable(struct clk *clk)
+{
+	unsigned long flags;
+
+	if (unlikely(IS_ERR_OR_NULL(clk)))
+		return;
+
+	WARN_ON(!clk->usage);
+
+	spin_lock_irqsave(&clocks_lock, flags);
+	if (--clk->usage == 0 && clk->ops && clk->ops->disable)
+		clk->ops->disable(clk);
+	spin_unlock_irqrestore(&clocks_lock, flags);
+
+	if (clk->parent)
+		clk_disable(clk->parent);
+}
+EXPORT_SYMBOL(clk_disable);
+
+unsigned long clk_get_rate(struct clk *clk)
+{
+	if (unlikely(IS_ERR_OR_NULL(clk)))
+		return 0;
+
+	if (clk->rate)
+		return clk->rate;
+
+	if (clk->ops && clk->ops->get_rate)
+		return clk->ops->get_rate(clk);
+
+	return clk_get_rate(clk->parent);
+}
+EXPORT_SYMBOL(clk_get_rate);
+
+long clk_round_rate(struct clk *clk, unsigned long rate)
+{
+	if (unlikely(IS_ERR_OR_NULL(clk)))
+		return 0;
+
+	if (clk->ops && clk->ops->round_rate)
+		return clk->ops->round_rate(clk, rate);
+
+	return 0;
+}
+EXPORT_SYMBOL(clk_round_rate);
+
+int clk_set_rate(struct clk *clk, unsigned long rate)
+{
+	if (unlikely(IS_ERR_OR_NULL(clk)))
+		return -EINVAL;
+
+	if (!clk->ops || !clk->ops->set_rate)
+		return -EINVAL;
+
+	return clk->ops->set_rate(clk, rate);
+}
+EXPORT_SYMBOL(clk_set_rate);
+
+int clk_set_parent(struct clk *clk, struct clk *parent)
+{
+	int ret;
+	unsigned long flags;
+
+	if (unlikely(IS_ERR_OR_NULL(clk)))
+		return -EINVAL;
+
+	if (!clk->ops || !clk->ops->set_parent)
+		return -EINVAL;
+
+	spin_lock_irqsave(&clocks_lock, flags);
+	ret = clk->ops->set_parent(clk, parent);
+	if (!ret) {
+		parent->usage += clk->usage;
+		clk->parent->usage -= clk->usage;
+		BUG_ON(clk->parent->usage < 0);
+		clk->parent = parent;
+	}
+	spin_unlock_irqrestore(&clocks_lock, flags);
+	return ret;
+}
+EXPORT_SYMBOL(clk_set_parent);
+
+struct clk *clk_get_parent(struct clk *clk)
+{
+	unsigned long flags;
+
+	if (unlikely(IS_ERR_OR_NULL(clk)))
+		return NULL;
+
+	if (!clk->ops || !clk->ops->get_parent)
+		return clk->parent;
+
+	spin_lock_irqsave(&clocks_lock, flags);
+	clk->parent = clk->ops->get_parent(clk);
+	spin_unlock_irqrestore(&clocks_lock, flags);
+	return clk->parent;
+}
+EXPORT_SYMBOL(clk_get_parent);
+
+static void __init sirfsoc_clk_init(void)
+{
+	clkdev_add_table(onchip_clks, ARRAY_SIZE(onchip_clks));
+}
+
+static struct of_device_id clkc_ids[] = {
+	{ .compatible = "sirf,prima2-clkc" },
+	{},
+};
+
+void __init sirfsoc_of_clk_init(void)
+{
+	struct device_node *np;
+	struct resource res;
+	struct map_desc sirfsoc_clkc_iodesc = {
+		.virtual = SIRFSOC_CLOCK_VA_BASE,
+		.type    = MT_DEVICE,
+	};
+
+	np = of_find_matching_node(NULL, clkc_ids);
+	if (!np)
+		panic("unable to find compatible clkc node in dtb\n");
+
+	if (of_address_to_resource(np, 0, &res))
+		panic("unable to find clkc range in dtb");
+	of_node_put(np);
+
+	sirfsoc_clkc_iodesc.pfn = __phys_to_pfn(res.start);
+	sirfsoc_clkc_iodesc.length = 1 + res.end - res.start;
+
+	iotable_init(&sirfsoc_clkc_iodesc, 1);
+
+	sirfsoc_clk_init();
+}