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-rw-r--r--arch/arm/mach-prima2/clock.c509
1 files changed, 509 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..f9a2aaf63f71
--- /dev/null
+++ b/arch/arm/mach-prima2/clock.c
@@ -0,0 +1,509 @@
+/*
+ * 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();
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-18 01:36:06 +0100