mx27: basic cpu support

This patch adds generic code to support Freescale's i.MX27 SoCs.

Signed-off-by: Ilya Yanok <yanok@emcraft.com>

4 files changed, 533 insertions, 0 deletions

diff --git a/cpu/arm926ejs/mx27/Makefile b/cpu/arm926ejs/mx27/Makefile
new file mode 100644
index 0000000..67d1b0e
--- /dev/null
+++ b/cpu/arm926ejs/mx27/Makefile
@@ -0,0 +1,44 @@
+#
+# (C) Copyright 2000-2006
+# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+#
+# See file CREDITS for list of people who contributed to this
+# project.
+#
+# 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
+
+include $(TOPDIR)/config.mk
+
+LIB	= $(obj)lib$(SOC).a
+
+COBJS	= generic.o reset.o timer.o
+
+SRCS	:= $(SOBJS:.o=.S) $(COBJS:.o=.c)
+OBJS	:= $(addprefix $(obj),$(SOBJS) $(COBJS))
+
+all:	$(obj).depend $(LIB)
+
+$(LIB):	$(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
+
+#########################################################################
+
+# defines $(obj).depend target
+include $(SRCTREE)/rules.mk
+
+sinclude $(obj).depend
+
+#########################################################################
diff --git a/cpu/arm926ejs/mx27/generic.c b/cpu/arm926ejs/mx27/generic.c
new file mode 100644
index 0000000..eab54d8
--- /dev/null
+++ b/cpu/arm926ejs/mx27/generic.c
@@ -0,0 +1,241 @@
+/*
+ *  Copyright (c) 2008 Eric Jarrige <eric.jarrige@armadeus.org>
+ *  Copyright (c) 2009 Ilya Yanok <yanok@emcraft.com>
+ *
+ * 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
+ */
+
+#include <common.h>
+#include <div64.h>
+#include <asm/io.h>
+#include <asm/arch/imx-regs.h>
+
+/*
+ *  get the system pll clock in Hz
+ *
+ *                  mfi + mfn / (mfd +1)
+ *  f = 2 * f_ref * --------------------
+ *                        pd + 1
+ */
+unsigned int imx_decode_pll(unsigned int pll, unsigned int f_ref)
+{
+	unsigned int mfi = (pll >> 10) & 0xf;
+	unsigned int mfn = pll & 0x3ff;
+	unsigned int mfd = (pll >> 16) & 0x3ff;
+	unsigned int pd =  (pll >> 26) & 0xf;
+
+	mfi = mfi <= 5 ? 5 : mfi;
+
+	return lldiv(2 * (u64)f_ref * (mfi * (mfd + 1) + mfn),
+			(mfd + 1) * (pd + 1));
+}
+
+static ulong clk_in_32k(void)
+{
+	return 1024 * CONFIG_MX27_CLK32;
+}
+
+static ulong clk_in_26m(void)
+{
+	struct pll_regs *pll = (struct pll_regs *)IMX_PLL_BASE;
+
+	if (readl(&pll->cscr) & CSCR_OSC26M_DIV1P5) {
+		/* divide by 1.5 */
+		return 26000000 * 2 / 3;
+	} else {
+		return 26000000;
+	}
+}
+
+ulong imx_get_mpllclk(void)
+{
+	struct pll_regs *pll = (struct pll_regs *)IMX_PLL_BASE;
+	ulong cscr = readl(&pll->cscr);
+	ulong fref;
+
+	if (cscr & CSCR_MCU_SEL)
+		fref = clk_in_26m();
+	else
+		fref = clk_in_32k();
+
+	return imx_decode_pll(readl(&pll->mpctl0), fref);
+}
+
+ulong imx_get_armclk(void)
+{
+	struct pll_regs *pll = (struct pll_regs *)IMX_PLL_BASE;
+	ulong cscr = readl(&pll->cscr);
+	ulong fref = imx_get_mpllclk();
+	ulong div;
+
+	if (!(cscr & CSCR_ARM_SRC_MPLL))
+		fref = lldiv((fref * 2), 3);
+
+	div = ((cscr >> 12) & 0x3) + 1;
+
+	return lldiv(fref, div);
+}
+
+ulong imx_get_ahbclk(void)
+{
+	struct pll_regs *pll = (struct pll_regs *)IMX_PLL_BASE;
+	ulong cscr = readl(&pll->cscr);
+	ulong fref = imx_get_mpllclk();
+	ulong div;
+
+	div = ((cscr >> 8) & 0x3) + 1;
+
+	return lldiv(fref * 2, 3 * div);
+}
+
+ulong imx_get_spllclk(void)
+{
+	struct pll_regs *pll = (struct pll_regs *)IMX_PLL_BASE;
+	ulong cscr = readl(&pll->cscr);
+	ulong fref;
+
+	if (cscr & CSCR_SP_SEL)
+		fref = clk_in_26m();
+	else
+		fref = clk_in_32k();
+
+	return imx_decode_pll(readl(&pll->spctl0), fref);
+}
+
+static ulong imx_decode_perclk(ulong div)
+{
+	return lldiv((imx_get_mpllclk() * 2), (div * 3));
+}
+
+ulong imx_get_perclk1(void)
+{
+	struct pll_regs *pll = (struct pll_regs *)IMX_PLL_BASE;
+
+	return imx_decode_perclk((readl(&pll->pcdr1) & 0x3f) + 1);
+}
+
+ulong imx_get_perclk2(void)
+{
+	struct pll_regs *pll = (struct pll_regs *)IMX_PLL_BASE;
+
+	return imx_decode_perclk(((readl(&pll->pcdr1) >> 8) & 0x3f) + 1);
+}
+
+ulong imx_get_perclk3(void)
+{
+	struct pll_regs *pll = (struct pll_regs *)IMX_PLL_BASE;
+
+	return imx_decode_perclk(((readl(&pll->pcdr1) >> 16) & 0x3f) + 1);
+}
+
+ulong imx_get_perclk4(void)
+{
+	struct pll_regs *pll = (struct pll_regs *)IMX_PLL_BASE;
+
+	return imx_decode_perclk(((readl(&pll->pcdr1) >> 24) & 0x3f) + 1);
+}
+
+#if defined(CONFIG_DISPLAY_CPUINFO)
+int print_cpuinfo (void)
+{
+	char buf[32];
+
+	printf("CPU:   Freescale i.MX27 at %s MHz\n\n",
+			strmhz(buf, imx_get_mpllclk()));
+	return 0;
+}
+#endif
+
+void imx_gpio_mode(int gpio_mode)
+{
+	struct gpio_regs *regs = (struct gpio_regs *)IMX_GPIO_BASE;
+	unsigned int pin = gpio_mode & GPIO_PIN_MASK;
+	unsigned int port = (gpio_mode & GPIO_PORT_MASK) >> GPIO_PORT_SHIFT;
+	unsigned int ocr = (gpio_mode & GPIO_OCR_MASK) >> GPIO_OCR_SHIFT;
+	unsigned int aout = (gpio_mode & GPIO_AOUT_MASK) >> GPIO_AOUT_SHIFT;
+	unsigned int bout = (gpio_mode & GPIO_BOUT_MASK) >> GPIO_BOUT_SHIFT;
+	unsigned int tmp;
+
+	/* Pullup enable */
+	if (gpio_mode & GPIO_PUEN) {
+		writel(readl(&regs->port[port].puen) | (1 << pin),
+				&regs->port[port].puen);
+	} else {
+		writel(readl(&regs->port[port].puen) & ~(1 << pin),
+				&regs->port[port].puen);
+	}
+
+	/* Data direction */
+	if (gpio_mode & GPIO_OUT) {
+		writel(readl(&regs->port[port].ddir) | 1 << pin,
+				&regs->port[port].ddir);
+	} else {
+		writel(readl(&regs->port[port].ddir) & ~(1 << pin),
+				&regs->port[port].ddir);
+	}
+
+	/* Primary / alternate function */
+	if (gpio_mode & GPIO_AF) {
+		writel(readl(&regs->port[port].gpr) | (1 << pin),
+				&regs->port[port].gpr);
+	} else {
+		writel(readl(&regs->port[port].gpr) & ~(1 << pin),
+				&regs->port[port].gpr);
+	}
+
+	/* use as gpio? */
+	if (!(gpio_mode & (GPIO_PF | GPIO_AF))) {
+		writel(readl(&regs->port[port].gius) | (1 << pin),
+				&regs->port[port].gius);
+	} else {
+		writel(readl(&regs->port[port].gius) & ~(1 << pin),
+				&regs->port[port].gius);
+	}
+
+	/* Output / input configuration */
+	if (pin < 16) {
+		tmp = readl(&regs->port[port].ocr1);
+		tmp &= ~(3 << (pin * 2));
+		tmp |= (ocr << (pin * 2));
+		writel(tmp, &regs->port[port].ocr1);
+
+		writel(readl(&regs->port[port].iconfa1) & ~(3 << (pin * 2)),
+				&regs->port[port].iconfa1);
+		writel(readl(&regs->port[port].iconfa1) | aout << (pin * 2),
+				&regs->port[port].iconfa1);
+		writel(readl(&regs->port[port].iconfb1) & ~(3 << (pin * 2)),
+				&regs->port[port].iconfb1);
+		writel(readl(&regs->port[port].iconfb1) | bout << (pin * 2),
+				&regs->port[port].iconfb1);
+	} else {
+		pin -= 16;
+
+		tmp = readl(&regs->port[port].ocr2);
+		tmp &= ~(3 << (pin * 2));
+		tmp |= (ocr << (pin * 2));
+		writel(tmp, &regs->port[port].ocr2);
+
+		writel(readl(&regs->port[port].iconfa2) & ~(3 << (pin * 2)),
+				&regs->port[port].iconfa2);
+		writel(readl(&regs->port[port].iconfa2) | aout << (pin * 2),
+				&regs->port[port].iconfa2);
+		writel(readl(&regs->port[port].iconfb2) & ~(3 << (pin * 2)),
+				&regs->port[port].iconfb2);
+		writel(readl(&regs->port[port].iconfb2) | bout << (pin * 2),
+				&regs->port[port].iconfb2);
+	}
+}
+
diff --git a/cpu/arm926ejs/mx27/reset.c b/cpu/arm926ejs/mx27/reset.c
new file mode 100644
index 0000000..6c54eaf
--- /dev/null
+++ b/cpu/arm926ejs/mx27/reset.c
@@ -0,0 +1,57 @@
+/*
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Marius Groeger <mgroeger@sysgo.de>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Alex Zuepke <azu@sysgo.de>
+ *
+ * (C) Copyright 2002
+ * Gary Jennejohn, DENX Software Engineering, <gj@denx.de>
+ *
+ * (C) Copyright 2009
+ * Ilya Yanok, Emcraft Systems Ltd, <yanok@emcraft.com>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch/imx-regs.h>
+
+/*
+ * Reset the cpu by setting up the watchdog timer and let it time out
+ */
+void reset_cpu (ulong ignored)
+{
+	struct wdog_regs *regs = (struct wdog_regs *)IMX_WDT_BASE;
+	/* Disable watchdog and set Time-Out field to 0 */
+	writel(0x00000000, &regs->wcr);
+
+	/* Write Service Sequence */
+	writel(0x00005555, &regs->wsr);
+	writel(0x0000AAAA, &regs->wsr);
+
+	/* Enable watchdog */
+	writel(WCR_WDE, &regs->wcr);
+
+	while (1);
+	/*NOTREACHED*/
+}
diff --git a/cpu/arm926ejs/mx27/timer.c b/cpu/arm926ejs/mx27/timer.c
new file mode 100644
index 0000000..d22252e
--- /dev/null
+++ b/cpu/arm926ejs/mx27/timer.c
@@ -0,0 +1,191 @@
+/*
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Marius Groeger <mgroeger@sysgo.de>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Alex Zuepke <azu@sysgo.de>
+ *
+ * (C) Copyright 2002
+ * Gary Jennejohn, DENX Software Engineering, <gj@denx.de>
+ *
+ * (C) Copyright 2009
+ * Ilya Yanok, Emcraft Systems Ltd, <yanok@emcraft.com>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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
+ */
+
+#include <common.h>
+#include <div64.h>
+#include <asm/io.h>
+#include <asm/arch/imx-regs.h>
+
+/* General purpose timers bitfields */
+#define GPTCR_SWR		(1 << 15)	/* Software reset	*/
+#define GPTCR_FRR		(1 << 8)	/* Freerun / restart	*/
+#define GPTCR_CLKSOURCE_32	(4 << 1)	/* Clock source		*/
+#define GPTCR_TEN		1		/* Timer enable		*/
+
+static ulong timestamp;
+static ulong lastinc;
+
+/*
+ * "time" is measured in 1 / CONFIG_SYS_HZ seconds,
+ * "tick" is internal timer period
+ */
+#ifdef CONFIG_MX27_TIMER_HIGH_PRECISION
+/* ~0.4% error - measured with stop-watch on 100s boot-delay */
+static inline unsigned long long tick_to_time(unsigned long long tick)
+{
+	tick *= CONFIG_SYS_HZ;
+	do_div(tick, CONFIG_MX27_CLK32);
+	return tick;
+}
+
+static inline unsigned long long time_to_tick(unsigned long long time)
+{
+	time *= CONFIG_MX27_CLK32;
+	do_div(time, CONFIG_SYS_HZ);
+	return time;
+}
+
+static inline unsigned long long us_to_tick(unsigned long long us)
+{
+	us = us * CONFIG_MX27_CLK32 + 999999;
+	do_div(us, 1000000);
+	return us;
+}
+#else
+/* ~2% error */
+#define TICK_PER_TIME	((CONFIG_MX27_CLK32 + CONFIG_SYS_HZ / 2) / \
+		CONFIG_SYS_HZ)
+#define US_PER_TICK	(1000000 / CONFIG_MX27_CLK32)
+
+static inline unsigned long long tick_to_time(unsigned long long tick)
+{
+	do_div(tick, TICK_PER_TIME);
+	return tick;
+}
+
+static inline unsigned long long time_to_tick(unsigned long long time)
+{
+	return time * TICK_PER_TIME;
+}
+
+static inline unsigned long long us_to_tick(unsigned long long us)
+{
+	us += US_PER_TICK - 1;
+	do_div(us, US_PER_TICK);
+	return us;
+}
+#endif
+
+/* nothing really to do with interrupts, just starts up a counter. */
+/* The 32768Hz 32-bit timer overruns in 131072 seconds */
+int timer_init(void)
+{
+	int i;
+	struct gpt_regs *regs = (struct gpt_regs *)IMX_TIM1_BASE;
+	struct pll_regs *pll = (struct pll_regs *)IMX_PLL_BASE;
+
+	/* setup GP Timer 1 */
+	writel(GPTCR_SWR, &regs->gpt_tctl);
+
+	writel(readl(&pll->pccr0) | PCCR0_GPT1_EN, &pll->pccr0);
+	writel(readl(&pll->pccr1) | PCCR1_PERCLK1_EN, &pll->pccr1);
+
+	for (i = 0; i < 100; i++)
+		writel(0, &regs->gpt_tctl); /* We have no udelay by now */
+	writel(0, &regs->gpt_tprer); /* 32Khz */
+	/* Freerun Mode, PERCLK1 input */
+	writel(readl(&regs->gpt_tctl) | GPTCR_CLKSOURCE_32 | GPTCR_FRR,
+			&regs->gpt_tctl);
+	writel(readl(&regs->gpt_tctl) | GPTCR_TEN, &regs->gpt_tctl);
+
+	return 0;
+}
+
+void reset_timer_masked(void)
+{
+	struct gpt_regs *regs = (struct gpt_regs *)IMX_TIM1_BASE;
+	/* reset time */
+	/* capture current incrementer value time */
+	lastinc = readl(&regs->gpt_tcn);
+	timestamp = 0; /* start "advancing" time stamp from 0 */
+}
+
+void reset_timer(void)
+{
+	reset_timer_masked();
+}
+
+unsigned long long get_ticks (void)
+{
+	struct gpt_regs *regs = (struct gpt_regs *)IMX_TIM1_BASE;
+	ulong now = readl(&regs->gpt_tcn); /* current tick value */
+
+	if (now >= lastinc) {
+		/*
+		 * normal mode (non roll)
+		 * move stamp forward with absolut diff ticks
+		 */
+		timestamp += (now - lastinc);
+	} else {
+		/* we have rollover of incrementer */
+		timestamp += (0xFFFFFFFF - lastinc) + now;
+	}
+	lastinc = now;
+	return timestamp;
+}
+
+ulong get_timer_masked (void)
+{
+	/*
+	 * get_ticks() returns a long long (64 bit), it wraps in
+	 * 2^64 / CONFIG_MX27_CLK32 = 2^64 / 2^15 = 2^49 ~ 5 * 10^14 (s) ~
+	 * 5 * 10^9 days... and get_ticks() * CONFIG_SYS_HZ wraps in
+	 * 5 * 10^6 days - long enough.
+	 */
+	return tick_to_time(get_ticks());
+}
+
+ulong get_timer (ulong base)
+{
+	return get_timer_masked () - base;
+}
+
+void set_timer (ulong t)
+{
+	timestamp = time_to_tick(t);
+}
+
+/* delay x useconds AND perserve advance timstamp value */
+void udelay (unsigned long usec)
+{
+	unsigned long long tmp;
+	ulong tmo;
+
+	tmo = us_to_tick(usec);
+	tmp = get_ticks() + tmo;	/* get current timestamp */
+
+	while (get_ticks() < tmp)	/* loop till event */
+		 /*NOP*/;
+}
+