From 5cccd37ea15970846a93b4b01fafd6e043bafe8e Mon Sep 17 00:00:00 2001
From: dmitry pervushin <dpervushin@embeddedalley.com>
Date: Thu, 23 Apr 2009 12:24:13 +0100
Subject: [ARM] 5477/1: Freescale STMP platform support [6/10]

Sources: common STMP3xxx platform support

Signed-off-by: dmitry pervushin <dpervushin@embeddedalley.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
---
 arch/arm/plat-stmp3xxx/core.c | 127 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 127 insertions(+)
 create mode 100644 arch/arm/plat-stmp3xxx/core.c

(limited to 'arch/arm/plat-stmp3xxx/core.c')

diff --git a/arch/arm/plat-stmp3xxx/core.c b/arch/arm/plat-stmp3xxx/core.c
new file mode 100644
index 00000000000..6e2fef1639b
--- /dev/null
+++ b/arch/arm/plat-stmp3xxx/core.c
@@ -0,0 +1,127 @@
+/*
+ * Freescale STMP37XX/STMP378X core routines
+ *
+ * Embedded Alley Solutions, Inc <source@embeddedalley.com>
+ *
+ * Copyright 2008 Freescale Semiconductor, Inc. All Rights Reserved.
+ * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved.
+ */
+
+/*
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/io.h>
+
+#include <mach/stmp3xxx.h>
+#include <mach/dma.h>
+#include <mach/regs-clkctrl.h>
+
+static int __stmp3xxx_reset_block(void __iomem *hwreg, int just_enable)
+{
+	u32 c;
+	int timeout;
+
+	/* the process of software reset of IP block is done
+	   in several steps:
+
+	   - clear SFTRST and wait for block is enabled;
+	   - clear clock gating (CLKGATE bit);
+	   - set the SFTRST again and wait for block is in reset;
+	   - clear SFTRST and wait for reset completion.
+	*/
+	c = __raw_readl(hwreg);
+	c &= ~(1<<31);		/* clear SFTRST */
+	__raw_writel(c, hwreg);
+	for (timeout = 1000000; timeout > 0; timeout--)
+		/* still in SFTRST state ? */
+		if ((__raw_readl(hwreg) & (1<<31)) == 0)
+			break;
+	if (timeout <= 0) {
+		printk(KERN_ERR"%s(%p): timeout when enabling\n",
+				__func__, hwreg);
+		return -ETIME;
+	}
+
+	c = __raw_readl(hwreg);
+	c &= ~(1<<30);		/* clear CLKGATE */
+	__raw_writel(c, hwreg);
+
+	if (!just_enable) {
+		c = __raw_readl(hwreg);
+		c |= (1<<31);		/* now again set SFTRST */
+		__raw_writel(c, hwreg);
+		for (timeout = 1000000; timeout > 0; timeout--)
+			/* poll until CLKGATE set */
+			if (__raw_readl(hwreg) & (1<<30))
+				break;
+		if (timeout <= 0) {
+			printk(KERN_ERR"%s(%p): timeout when resetting\n",
+					__func__, hwreg);
+			return -ETIME;
+		}
+
+		c = __raw_readl(hwreg);
+		c &= ~(1<<31);		/* clear SFTRST */
+		__raw_writel(c, hwreg);
+		for (timeout = 1000000; timeout > 0; timeout--)
+			/* still in SFTRST state ? */
+			if ((__raw_readl(hwreg) & (1<<31)) == 0)
+				break;
+		if (timeout <= 0) {
+			printk(KERN_ERR"%s(%p): timeout when enabling "
+					"after reset\n", __func__, hwreg);
+			return -ETIME;
+		}
+
+		c = __raw_readl(hwreg);
+		c &= ~(1<<30);		/* clear CLKGATE */
+		__raw_writel(c, hwreg);
+	}
+	for (timeout = 1000000; timeout > 0; timeout--)
+		/* still in SFTRST state ? */
+		if ((__raw_readl(hwreg) & (1<<30)) == 0)
+			break;
+
+	if (timeout <= 0) {
+		printk(KERN_ERR"%s(%p): timeout when unclockgating\n",
+				__func__, hwreg);
+		return -ETIME;
+	}
+
+	return 0;
+}
+
+int stmp3xxx_reset_block(void __iomem *hwreg, int just_enable)
+{
+	int try = 10;
+	int r;
+
+	while (try--) {
+		r = __stmp3xxx_reset_block(hwreg, just_enable);
+		if (!r)
+			break;
+		pr_debug("%s: try %d failed\n", __func__, 10 - try);
+	}
+	return r;
+}
+EXPORT_SYMBOL(stmp3xxx_reset_block);
+
+struct platform_device stmp3xxx_dbguart = {
+	.name = "stmp3xxx-dbguart",
+	.id = -1,
+};
+
+void __init stmp3xxx_init(void)
+{
+	/* Turn off auto-slow and other tricks */
+	HW_CLKCTRL_HBUS_CLR(0x07f00000U);
+
+	stmp3xxx_dma_init();
+}
-- 
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