avionic design with actual uboot and tooling

submodule of avionic design uboot bootloader and with included tools to
get you started , read readme.md and readme-tk1-loader.md

u-boot/arch/arm/mach-uniphier/pll/Makefile

@@ -0,0 +1,8 @@
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+obj-$(CONFIG_ARCH_UNIPHIER_SLD3)	+= pll-init-sld3.o pll-spectrum-sld3.o
+obj-$(CONFIG_ARCH_UNIPHIER_LD4)		+= pll-init-ld4.o pll-spectrum-ld4.o
+obj-$(CONFIG_ARCH_UNIPHIER_PRO4)	+= pll-init-pro4.o pll-spectrum-ld4.o
+obj-$(CONFIG_ARCH_UNIPHIER_SLD8)	+= pll-init-sld8.o pll-spectrum-ld4.o

u-boot/arch/arm/mach-uniphier/pll/pll-init-ld4.c

@@ -0,0 +1,204 @@
+/*
+ * Copyright (C) 2011-2015 Masahiro Yamada <yamada.masahiro@socionext.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <linux/err.h>
+#include <linux/io.h>
+
+#include "../init.h"
+#include "../sc-regs.h"
+#include "../sg-regs.h"
+
+#undef DPLL_SSC_RATE_1PER
+
+static int dpll_init(unsigned int dram_freq)
+{
+	u32 tmp;
+
+	/*
+	 * Set Frequency
+	 * Set 0xc(1600MHz)/0xd(1333MHz)/0xe(1066MHz)
+	 * to FOUT (DPLLCTRL.bit[29:20])
+	 */
+	tmp = readl(SC_DPLLCTRL);
+	tmp &= ~0x000f0000;
+	switch (dram_freq) {
+	case 1333:
+		tmp |= 0x000d0000;
+		break;
+	case 1600:
+		tmp |= 0x000c0000;
+		break;
+	default:
+		pr_err("Unsupported frequency");
+		return -EINVAL;
+	}
+
+#if defined(DPLL_SSC_RATE_1PER)
+	tmp &= ~SC_DPLLCTRL_SSC_RATE;
+#else
+	tmp |= SC_DPLLCTRL_SSC_RATE;
+#endif
+	writel(tmp, SC_DPLLCTRL);
+
+	tmp = readl(SC_DPLLCTRL2);
+	tmp |= SC_DPLLCTRL2_NRSTDS;
+	writel(tmp, SC_DPLLCTRL2);
+
+	return 0;
+}
+
+static void upll_init(void)
+{
+	u32 tmp, clk_mode_upll, clk_mode_axosel;
+
+	tmp = readl(SG_PINMON0);
+	clk_mode_upll   = tmp & SG_PINMON0_CLK_MODE_UPLLSRC_MASK;
+	clk_mode_axosel = tmp & SG_PINMON0_CLK_MODE_AXOSEL_MASK;
+
+	/* set 0 to SNRT(UPLLCTRL.bit28) and K_LD(UPLLCTRL.bit[27]) */
+	tmp = readl(SC_UPLLCTRL);
+	tmp &= ~0x18000000;
+	writel(tmp, SC_UPLLCTRL);
+
+	if (clk_mode_upll == SG_PINMON0_CLK_MODE_UPLLSRC_DEFAULT) {
+		if (clk_mode_axosel == SG_PINMON0_CLK_MODE_AXOSEL_25000KHZ_U ||
+		    clk_mode_axosel == SG_PINMON0_CLK_MODE_AXOSEL_25000KHZ_A) {
+			/* AXO: 25MHz */
+			tmp &= ~0x07ffffff;
+			tmp |= 0x0228f5c0;
+		} else {
+			/* AXO: default 24.576MHz */
+			tmp &= ~0x07ffffff;
+			tmp |= 0x02328000;
+		}
+	}
+
+	writel(tmp, SC_UPLLCTRL);
+
+	/* set 1 to K_LD(UPLLCTRL.bit[27]) */
+	tmp |= 0x08000000;
+	writel(tmp, SC_UPLLCTRL);
+
+	/* wait 10 usec */
+	udelay(10);
+
+	/* set 1 to SNRT(UPLLCTRL.bit[28]) */
+	tmp |= 0x10000000;
+	writel(tmp, SC_UPLLCTRL);
+}
+
+static void vpll_init(void)
+{
+	u32 tmp, clk_mode_axosel;
+
+	tmp = readl(SG_PINMON0);
+	clk_mode_axosel = tmp & SG_PINMON0_CLK_MODE_AXOSEL_MASK;
+
+	/* set 1 to VPLA27WP and VPLA27WP */
+	tmp = readl(SC_VPLL27ACTRL);
+	tmp |= 0x00000001;
+	writel(tmp, SC_VPLL27ACTRL);
+	tmp = readl(SC_VPLL27BCTRL);
+	tmp |= 0x00000001;
+	writel(tmp, SC_VPLL27BCTRL);
+
+	/* Set 0 to VPLA_K_LD and VPLB_K_LD */
+	tmp = readl(SC_VPLL27ACTRL3);
+	tmp &= ~0x10000000;
+	writel(tmp, SC_VPLL27ACTRL3);
+	tmp = readl(SC_VPLL27BCTRL3);
+	tmp &= ~0x10000000;
+	writel(tmp, SC_VPLL27BCTRL3);
+
+	/* Set 0 to VPLA_SNRST and VPLB_SNRST */
+	tmp = readl(SC_VPLL27ACTRL2);
+	tmp &= ~0x10000000;
+	writel(tmp, SC_VPLL27ACTRL2);
+	tmp = readl(SC_VPLL27BCTRL2);
+	tmp &= ~0x10000000;
+	writel(tmp, SC_VPLL27BCTRL2);
+
+	/* Set 0x20 to VPLA_SNRST and VPLB_SNRST */
+	tmp = readl(SC_VPLL27ACTRL2);
+	tmp &= ~0x0000007f;
+	tmp |= 0x00000020;
+	writel(tmp, SC_VPLL27ACTRL2);
+	tmp = readl(SC_VPLL27BCTRL2);
+	tmp &= ~0x0000007f;
+	tmp |= 0x00000020;
+	writel(tmp, SC_VPLL27BCTRL2);
+
+	if (clk_mode_axosel == SG_PINMON0_CLK_MODE_AXOSEL_25000KHZ_U ||
+	    clk_mode_axosel == SG_PINMON0_CLK_MODE_AXOSEL_25000KHZ_A) {
+		/* AXO: 25MHz */
+		tmp = readl(SC_VPLL27ACTRL3);
+		tmp &= ~0x000fffff;
+		tmp |= 0x00066664;
+		writel(tmp, SC_VPLL27ACTRL3);
+		tmp = readl(SC_VPLL27BCTRL3);
+		tmp &= ~0x000fffff;
+		tmp |= 0x00066664;
+		writel(tmp, SC_VPLL27BCTRL3);
+	} else {
+		/* AXO: default 24.576MHz */
+		tmp = readl(SC_VPLL27ACTRL3);
+		tmp &= ~0x000fffff;
+		tmp |= 0x000f5800;
+		writel(tmp, SC_VPLL27ACTRL3);
+		tmp = readl(SC_VPLL27BCTRL3);
+		tmp &= ~0x000fffff;
+		tmp |= 0x000f5800;
+		writel(tmp, SC_VPLL27BCTRL3);
+	}
+
+	/* Set 1 to VPLA_K_LD and VPLB_K_LD */
+	tmp = readl(SC_VPLL27ACTRL3);
+	tmp |= 0x10000000;
+	writel(tmp, SC_VPLL27ACTRL3);
+	tmp = readl(SC_VPLL27BCTRL3);
+	tmp |= 0x10000000;
+	writel(tmp, SC_VPLL27BCTRL3);
+
+	/* wait 10 usec */
+	udelay(10);
+
+	/* Set 0 to VPLA_SNRST and VPLB_SNRST */
+	tmp = readl(SC_VPLL27ACTRL2);
+	tmp |= 0x10000000;
+	writel(tmp, SC_VPLL27ACTRL2);
+	tmp = readl(SC_VPLL27BCTRL2);
+	tmp |= 0x10000000;
+	writel(tmp, SC_VPLL27BCTRL2);
+
+	/* set 0 to VPLA27WP and VPLA27WP */
+	tmp = readl(SC_VPLL27ACTRL);
+	tmp &= ~0x00000001;
+	writel(tmp, SC_VPLL27ACTRL);
+	tmp = readl(SC_VPLL27BCTRL);
+	tmp |= ~0x00000001;
+	writel(tmp, SC_VPLL27BCTRL);
+}
+
+int uniphier_ld4_pll_init(const struct uniphier_board_data *bd)
+{
+	int ret;
+
+	ret = dpll_init(bd->dram_freq);
+	if (ret)
+		return ret;
+	upll_init();
+	vpll_init();
+
+	/*
+	 * Wait 500 usec until dpll get stable
+	 * We wait 10 usec in upll_init() and vpll_init()
+	 * so 20 usec can be saved here.
+	 */
+	udelay(480);
+
+	return 0;
+}

u-boot/arch/arm/mach-uniphier/pll/pll-init-pro4.c

@@ -0,0 +1,164 @@
+/*
+ * Copyright (C) 2011-2015 Masahiro Yamada <yamada.masahiro@socionext.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <linux/err.h>
+#include <linux/io.h>
+
+#include "../init.h"
+#include "../sc-regs.h"
+#include "../sg-regs.h"
+
+#undef DPLL_SSC_RATE_1PER
+
+static int dpll_init(unsigned int dram_freq)
+{
+	u32 tmp;
+
+	/*
+	 * Set Frequency
+	 * Set 0xc(1600MHz)/0xd(1333MHz)/0xe(1066MHz)
+	 * to FOUT ( DPLLCTRL.bit[29:20] )
+	 */
+	tmp = readl(SC_DPLLCTRL);
+	tmp &= ~(0x000f0000);
+	switch (dram_freq) {
+	case 1333:
+		tmp |= 0x000d0000;
+		break;
+	case 1600:
+		tmp |= 0x000c0000;
+		break;
+	default:
+		pr_err("Unsupported frequency");
+		return -EINVAL;
+	}
+
+	/*
+	 * Set Moduration rate
+	 * Set 0x0(1%)/0x1(2%) to SSC_RATE(DPLLCTRL.bit[15])
+	 */
+#if defined(DPLL_SSC_RATE_1PER)
+	tmp &= ~0x00008000;
+#else
+	tmp |= 0x00008000;
+#endif
+	writel(tmp, SC_DPLLCTRL);
+
+	tmp = readl(SC_DPLLCTRL2);
+	tmp |= SC_DPLLCTRL2_NRSTDS;
+	writel(tmp, SC_DPLLCTRL2);
+
+	return 0;
+}
+
+static void vpll_init(void)
+{
+	u32 tmp, clk_mode_axosel;
+
+	/* Set VPLL27A &  VPLL27B */
+	tmp = readl(SG_PINMON0);
+	clk_mode_axosel = tmp & SG_PINMON0_CLK_MODE_AXOSEL_MASK;
+
+	/* 25MHz or 6.25MHz is default for Pro4R, no need to set VPLLA/B */
+	if (clk_mode_axosel == SG_PINMON0_CLK_MODE_AXOSEL_25000KHZ ||
+	    clk_mode_axosel == SG_PINMON0_CLK_MODE_AXOSEL_6250KHZ)
+		return;
+
+	/* Disable write protect of VPLL27ACTRL[2-7]*, VPLL27BCTRL[2-8] */
+	tmp = readl(SC_VPLL27ACTRL);
+	tmp |= 0x00000001;
+	writel(tmp, SC_VPLL27ACTRL);
+	tmp = readl(SC_VPLL27BCTRL);
+	tmp |= 0x00000001;
+	writel(tmp, SC_VPLL27BCTRL);
+
+	/* Unset VPLA_K_LD and VPLB_K_LD bit */
+	tmp = readl(SC_VPLL27ACTRL3);
+	tmp &= ~0x10000000;
+	writel(tmp, SC_VPLL27ACTRL3);
+	tmp = readl(SC_VPLL27BCTRL3);
+	tmp &= ~0x10000000;
+	writel(tmp, SC_VPLL27BCTRL3);
+
+	/* Set VPLA_M and VPLB_M to 0x20 */
+	tmp = readl(SC_VPLL27ACTRL2);
+	tmp &= ~0x0000007f;
+	tmp |= 0x00000020;
+	writel(tmp, SC_VPLL27ACTRL2);
+	tmp = readl(SC_VPLL27BCTRL2);
+	tmp &= ~0x0000007f;
+	tmp |= 0x00000020;
+	writel(tmp, SC_VPLL27BCTRL2);
+
+	if (clk_mode_axosel == SG_PINMON0_CLK_MODE_AXOSEL_25000KHZ ||
+	    clk_mode_axosel == SG_PINMON0_CLK_MODE_AXOSEL_6250KHZ) {
+		/* Set VPLA_K and VPLB_K for AXO: 25MHz */
+		tmp = readl(SC_VPLL27ACTRL3);
+		tmp &= ~0x000fffff;
+		tmp |= 0x00066666;
+		writel(tmp, SC_VPLL27ACTRL3);
+		tmp = readl(SC_VPLL27BCTRL3);
+		tmp &= ~0x000fffff;
+		tmp |= 0x00066666;
+		writel(tmp, SC_VPLL27BCTRL3);
+	} else {
+		/* Set VPLA_K and VPLB_K for AXO: 24.576 MHz */
+		tmp = readl(SC_VPLL27ACTRL3);
+		tmp &= ~0x000fffff;
+		tmp |= 0x000f5800;
+		writel(tmp, SC_VPLL27ACTRL3);
+		tmp = readl(SC_VPLL27BCTRL3);
+		tmp &= ~0x000fffff;
+		tmp |= 0x000f5800;
+		writel(tmp, SC_VPLL27BCTRL3);
+	}
+
+	/* wait 1 usec */
+	udelay(1);
+
+	/* Set VPLA_K_LD and VPLB_K_LD to load K parameters */
+	tmp = readl(SC_VPLL27ACTRL3);
+	tmp |= 0x10000000;
+	writel(tmp, SC_VPLL27ACTRL3);
+	tmp = readl(SC_VPLL27BCTRL3);
+	tmp |= 0x10000000;
+	writel(tmp, SC_VPLL27BCTRL3);
+
+	/* Unset VPLA_SNRST and VPLB_SNRST bit */
+	tmp = readl(SC_VPLL27ACTRL2);
+	tmp |= 0x10000000;
+	writel(tmp, SC_VPLL27ACTRL2);
+	tmp = readl(SC_VPLL27BCTRL2);
+	tmp |= 0x10000000;
+	writel(tmp, SC_VPLL27BCTRL2);
+
+	/* Enable write protect of VPLL27ACTRL[2-7]*, VPLL27BCTRL[2-8] */
+	tmp = readl(SC_VPLL27ACTRL);
+	tmp &= ~0x00000001;
+	writel(tmp, SC_VPLL27ACTRL);
+	tmp = readl(SC_VPLL27BCTRL);
+	tmp &= ~0x00000001;
+	writel(tmp, SC_VPLL27BCTRL);
+}
+
+int uniphier_pro4_pll_init(const struct uniphier_board_data *bd)
+{
+	int ret;
+
+	ret = dpll_init(bd->dram_freq);
+	if (ret)
+		return ret;
+	vpll_init();
+
+	/*
+	 * Wait 500 usec until dpll get stable
+	 * We wait 1 usec in vpll_init() so 1 usec can be saved here.
+	 */
+	udelay(499);
+
+	return 0;
+}

u-boot/arch/arm/mach-uniphier/pll/pll-init-sld3.c

@@ -0,0 +1,13 @@
+/*
+ * Copyright (C) 2011-2015 Masahiro Yamada <yamada.masahiro@socionext.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include "../init.h"
+
+int uniphier_sld3_pll_init(const struct uniphier_board_data *bd)
+{
+	/* add pll init code here */
+	return 0;
+}

u-boot/arch/arm/mach-uniphier/pll/pll-init-sld8.c

@@ -0,0 +1,205 @@
+/*
+ * Copyright (C) 2011-2015 Masahiro Yamada <yamada.masahiro@socionext.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <linux/io.h>
+
+#include "../init.h"
+#include "../sc-regs.h"
+#include "../sg-regs.h"
+
+static void dpll_init(void)
+{
+	u32 tmp;
+	/*
+	 * Set DPLL SSC parameters for DPLLCTRL3
+	 * [23]    DIVN_TEST    0x1
+	 * [22:16] DIVN         0x50
+	 * [10]    FREFSEL_TEST 0x1
+	 * [9:8]   FREFSEL      0x2
+	 * [4]     ICPD_TEST    0x1
+	 * [3:0]   ICPD         0xb
+	 */
+	tmp = readl(SC_DPLLCTRL3);
+	tmp &= ~0x00ff0717;
+	tmp |= 0x00d0061b;
+	writel(tmp, SC_DPLLCTRL3);
+
+	/*
+	 * Set DPLL SSC parameters for DPLLCTRL
+	 *                    <-1%>          <-2%>
+	 * [29:20] SSC_UPCNT 132 (0x084)    132  (0x084)
+	 * [14:0]  SSC_dK    6335(0x18bf)   12710(0x31a6)
+	 */
+	tmp = readl(SC_DPLLCTRL);
+	tmp &= ~0x3ff07fff;
+#ifdef CONFIG_DPLL_SSC_RATE_1PER
+	tmp |= 0x084018bf;
+#else
+	tmp |= 0x084031a6;
+#endif
+	writel(tmp, SC_DPLLCTRL);
+
+	/*
+	 * Set DPLL SSC parameters for DPLLCTRL2
+	 * [31:29]  SSC_STEP     0
+	 * [27]     SSC_REG_REF  1
+	 * [26:20]  SSC_M        79     (0x4f)
+	 * [19:0]   SSC_K        964689 (0xeb851)
+	 */
+	tmp = readl(SC_DPLLCTRL2);
+	tmp &= ~0xefffffff;
+	tmp |= 0x0cfeb851;
+	writel(tmp, SC_DPLLCTRL2);
+}
+
+static void upll_init(void)
+{
+	u32 tmp, clk_mode_upll, clk_mode_axosel;
+
+	tmp = readl(SG_PINMON0);
+	clk_mode_upll   = tmp & SG_PINMON0_CLK_MODE_UPLLSRC_MASK;
+	clk_mode_axosel = tmp & SG_PINMON0_CLK_MODE_AXOSEL_MASK;
+
+	/* set 0 to SNRT(UPLLCTRL.bit28) and K_LD(UPLLCTRL.bit[27]) */
+	tmp = readl(SC_UPLLCTRL);
+	tmp &= ~0x18000000;
+	writel(tmp, SC_UPLLCTRL);
+
+	if (clk_mode_upll == SG_PINMON0_CLK_MODE_UPLLSRC_DEFAULT) {
+		if (clk_mode_axosel == SG_PINMON0_CLK_MODE_AXOSEL_25000KHZ_U ||
+		    clk_mode_axosel == SG_PINMON0_CLK_MODE_AXOSEL_25000KHZ_A) {
+			/* AXO: 25MHz */
+			tmp &= ~0x07ffffff;
+			tmp |= 0x0228f5c0;
+		} else {
+			/* AXO: default 24.576MHz */
+			tmp &= ~0x07ffffff;
+			tmp |= 0x02328000;
+		}
+	}
+
+	writel(tmp, SC_UPLLCTRL);
+
+	/* set 1 to K_LD(UPLLCTRL.bit[27]) */
+	tmp |= 0x08000000;
+	writel(tmp, SC_UPLLCTRL);
+
+	/* wait 10 usec */
+	udelay(10);
+
+	/* set 1 to SNRT(UPLLCTRL.bit[28]) */
+	tmp |= 0x10000000;
+	writel(tmp, SC_UPLLCTRL);
+}
+
+static void vpll_init(void)
+{
+	u32 tmp, clk_mode_axosel;
+
+	tmp = readl(SG_PINMON0);
+	clk_mode_axosel = tmp & SG_PINMON0_CLK_MODE_AXOSEL_MASK;
+
+	/* set 1 to VPLA27WP and VPLA27WP */
+	tmp = readl(SC_VPLL27ACTRL);
+	tmp |= 0x00000001;
+	writel(tmp, SC_VPLL27ACTRL);
+	tmp = readl(SC_VPLL27BCTRL);
+	tmp |= 0x00000001;
+	writel(tmp, SC_VPLL27BCTRL);
+
+	/* Set 0 to VPLA_K_LD and VPLB_K_LD */
+	tmp = readl(SC_VPLL27ACTRL3);
+	tmp &= ~0x10000000;
+	writel(tmp, SC_VPLL27ACTRL3);
+	tmp = readl(SC_VPLL27BCTRL3);
+	tmp &= ~0x10000000;
+	writel(tmp, SC_VPLL27BCTRL3);
+
+	/* Set 0 to VPLA_SNRST and VPLB_SNRST */
+	tmp = readl(SC_VPLL27ACTRL2);
+	tmp &= ~0x10000000;
+	writel(tmp, SC_VPLL27ACTRL2);
+	tmp = readl(SC_VPLL27BCTRL2);
+	tmp &= ~0x10000000;
+	writel(tmp, SC_VPLL27BCTRL2);
+
+	/* Set 0x20 to VPLA_SNRST and VPLB_SNRST */
+	tmp = readl(SC_VPLL27ACTRL2);
+	tmp &= ~0x0000007f;
+	tmp |= 0x00000020;
+	writel(tmp, SC_VPLL27ACTRL2);
+	tmp = readl(SC_VPLL27BCTRL2);
+	tmp &= ~0x0000007f;
+	tmp |= 0x00000020;
+	writel(tmp, SC_VPLL27BCTRL2);
+
+	if (clk_mode_axosel == SG_PINMON0_CLK_MODE_AXOSEL_25000KHZ_U ||
+	    clk_mode_axosel == SG_PINMON0_CLK_MODE_AXOSEL_25000KHZ_A) {
+		/* AXO: 25MHz */
+		tmp = readl(SC_VPLL27ACTRL3);
+		tmp &= ~0x000fffff;
+		tmp |= 0x00066664;
+		writel(tmp, SC_VPLL27ACTRL3);
+		tmp = readl(SC_VPLL27BCTRL3);
+		tmp &= ~0x000fffff;
+		tmp |= 0x00066664;
+		writel(tmp, SC_VPLL27BCTRL3);
+	} else {
+		/* AXO: default 24.576MHz */
+		tmp = readl(SC_VPLL27ACTRL3);
+		tmp &= ~0x000fffff;
+		tmp |= 0x000f5800;
+		writel(tmp, SC_VPLL27ACTRL3);
+		tmp = readl(SC_VPLL27BCTRL3);
+		tmp &= ~0x000fffff;
+		tmp |= 0x000f5800;
+		writel(tmp, SC_VPLL27BCTRL3);
+	}
+
+	/* Set 1 to VPLA_K_LD and VPLB_K_LD */
+	tmp = readl(SC_VPLL27ACTRL3);
+	tmp |= 0x10000000;
+	writel(tmp, SC_VPLL27ACTRL3);
+	tmp = readl(SC_VPLL27BCTRL3);
+	tmp |= 0x10000000;
+	writel(tmp, SC_VPLL27BCTRL3);
+
+	/* wait 10 usec */
+	udelay(10);
+
+	/* Set 0 to VPLA_SNRST and VPLB_SNRST */
+	tmp = readl(SC_VPLL27ACTRL2);
+	tmp |= 0x10000000;
+	writel(tmp, SC_VPLL27ACTRL2);
+	tmp = readl(SC_VPLL27BCTRL2);
+	tmp |= 0x10000000;
+	writel(tmp, SC_VPLL27BCTRL2);
+
+	/* set 0 to VPLA27WP and VPLA27WP */
+	tmp = readl(SC_VPLL27ACTRL);
+	tmp &= ~0x00000001;
+	writel(tmp, SC_VPLL27ACTRL);
+	tmp = readl(SC_VPLL27BCTRL);
+	tmp |= ~0x00000001;
+	writel(tmp, SC_VPLL27BCTRL);
+}
+
+int uniphier_sld8_pll_init(const struct uniphier_board_data *bd)
+{
+	dpll_init();
+	upll_init();
+	vpll_init();
+
+	/*
+	 * Wait 500 usec until dpll get stable
+	 * We wait 10 usec in upll_init() and vpll_init()
+	 * so 20 usec can be saved here.
+	 */
+	udelay(480);
+
+	return 0;
+}

u-boot/arch/arm/mach-uniphier/pll/pll-spectrum-ld4.c

@@ -0,0 +1,21 @@
+/*
+ * Copyright (C) 2011-2015 Masahiro Yamada <yamada.masahiro@socionext.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <linux/io.h>
+
+#include "../init.h"
+#include "../sc-regs.h"
+
+int uniphier_ld4_enable_dpll_ssc(const struct uniphier_board_data *bd)
+{
+	u32 tmp;
+
+	tmp = readl(SC_DPLLCTRL);
+	tmp |= SC_DPLLCTRL_SSC_EN;
+	writel(tmp, SC_DPLLCTRL);
+
+	return 0;
+}

u-boot/arch/arm/mach-uniphier/pll/pll-spectrum-sld3.c

@@ -0,0 +1,22 @@
+/*
+ * Copyright (C) 2011-2015 Masahiro Yamada <yamada.masahiro@socionext.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <linux/io.h>
+
+#include "../init.h"
+#include "../sc-regs.h"
+
+int uniphier_sld3_enable_dpll_ssc(const struct uniphier_board_data *bd)
+{
+	u32 tmp;
+
+	tmp = readl(SC_DPLLCTRL);
+	tmp |= SC_DPLLCTRL_SSC_EN;
+	writel(tmp, SC_DPLLCTRL);
+
+	return 0;
+}