mx27: basic cpu support

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

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

1 files changed, 241 insertions, 0 deletions

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);
+	}
+}
+