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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /lib/stmp_device.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/stmp_device.c')
-rw-r--r--lib/stmp_device.c81
1 files changed, 81 insertions, 0 deletions
diff --git a/lib/stmp_device.c b/lib/stmp_device.c
new file mode 100644
index 000000000..a904656f4
--- /dev/null
+++ b/lib/stmp_device.c
@@ -0,0 +1,81 @@
+/*
+ * Copyright (C) 1999 ARM Limited
+ * Copyright (C) 2000 Deep Blue Solutions Ltd
+ * Copyright 2006-2007,2010 Freescale Semiconductor, Inc. All Rights Reserved.
+ * Copyright 2008 Juergen Beisert, kernel@pengutronix.de
+ * Copyright 2009 Ilya Yanok, Emcraft Systems Ltd, yanok@emcraft.com
+ * Copyright (C) 2011 Wolfram Sang, Pengutronix e.K.
+ *
+ * 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.
+ */
+
+#include <linux/io.h>
+#include <linux/errno.h>
+#include <linux/delay.h>
+#include <linux/compiler.h>
+#include <linux/export.h>
+#include <linux/stmp_device.h>
+
+#define STMP_MODULE_CLKGATE (1 << 30)
+#define STMP_MODULE_SFTRST (1 << 31)
+
+/*
+ * Clear the bit and poll it cleared. This is usually called with
+ * a reset address and mask being either SFTRST(bit 31) or CLKGATE
+ * (bit 30).
+ */
+static int stmp_clear_poll_bit(void __iomem *addr, u32 mask)
+{
+ int timeout = 0x400;
+
+ writel(mask, addr + STMP_OFFSET_REG_CLR);
+ udelay(1);
+ while ((readl(addr) & mask) && --timeout)
+ /* nothing */;
+
+ return !timeout;
+}
+
+int stmp_reset_block(void __iomem *reset_addr)
+{
+ int ret;
+ int timeout = 0x400;
+
+ /* clear and poll SFTRST */
+ ret = stmp_clear_poll_bit(reset_addr, STMP_MODULE_SFTRST);
+ if (unlikely(ret))
+ goto error;
+
+ /* clear CLKGATE */
+ writel(STMP_MODULE_CLKGATE, reset_addr + STMP_OFFSET_REG_CLR);
+
+ /* set SFTRST to reset the block */
+ writel(STMP_MODULE_SFTRST, reset_addr + STMP_OFFSET_REG_SET);
+ udelay(1);
+
+ /* poll CLKGATE becoming set */
+ while ((!(readl(reset_addr) & STMP_MODULE_CLKGATE)) && --timeout)
+ /* nothing */;
+ if (unlikely(!timeout))
+ goto error;
+
+ /* clear and poll SFTRST */
+ ret = stmp_clear_poll_bit(reset_addr, STMP_MODULE_SFTRST);
+ if (unlikely(ret))
+ goto error;
+
+ /* clear and poll CLKGATE */
+ ret = stmp_clear_poll_bit(reset_addr, STMP_MODULE_CLKGATE);
+ if (unlikely(ret))
+ goto error;
+
+ return 0;
+
+error:
+ pr_err("%s(%p): module reset timeout\n", __func__, reset_addr);
+ return -ETIMEDOUT;
+}
+EXPORT_SYMBOL(stmp_reset_block);