[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>

1 files changed, 127 insertions, 0 deletions

diff --git a/arch/arm/plat-stmp3xxx/core.c b/arch/arm/plat-stmp3xxx/core.c
new file mode 100644
index 000000000000..6e2fef1639b0
--- /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();
+}