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-rw-r--r--arch/arm/mach-sunxi/dram_helpers.c37
1 files changed, 37 insertions, 0 deletions
diff --git a/arch/arm/mach-sunxi/dram_helpers.c b/arch/arm/mach-sunxi/dram_helpers.c
new file mode 100644
index 00000000000..9a94e1b6795
--- /dev/null
+++ b/arch/arm/mach-sunxi/dram_helpers.c
@@ -0,0 +1,37 @@
+/*
+ * DRAM init helper functions
+ *
+ * (C) Copyright 2015 Hans de Goede <hdegoede@redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch/dram.h>
+
+/*
+ * Wait up to 1s for value to be set in given part of reg.
+ */
+void mctl_await_completion(u32 *reg, u32 mask, u32 val)
+{
+ unsigned long tmo = timer_get_us() + 1000000;
+
+ while ((readl(reg) & mask) != val) {
+ if (timer_get_us() > tmo)
+ panic("Timeout initialising DRAM\n");
+ }
+}
+
+/*
+ * Test if memory at offset offset matches memory at begin of DRAM
+ */
+bool mctl_mem_matches(u32 offset)
+{
+ /* Try to write different values to RAM at two addresses */
+ writel(0, CONFIG_SYS_SDRAM_BASE);
+ writel(0xaa55aa55, CONFIG_SYS_SDRAM_BASE + offset);
+ /* Check if the same value is actually observed when reading back */
+ return readl(CONFIG_SYS_SDRAM_BASE) ==
+ readl(CONFIG_SYS_SDRAM_BASE + offset);
+}