1 /*
2  * DRAM init helper functions
3  *
4  * (C) Copyright 2015 Hans de Goede <hdegoede@redhat.com>
5  *
6  * SPDX-License-Identifier:	GPL-2.0+
7  */
8 
9 #include <common.h>
10 #include <asm/barriers.h>
11 #include <asm/io.h>
12 #include <asm/arch/dram.h>
13 
14 /*
15  * Wait up to 1s for value to be set in given part of reg.
16  */
17 void mctl_await_completion(u32 *reg, u32 mask, u32 val)
18 {
19 	unsigned long tmo = timer_get_us() + 1000000;
20 
21 	while ((readl(reg) & mask) != val) {
22 		if (timer_get_us() > tmo)
23 			panic("Timeout initialising DRAM\n");
24 	}
25 }
26 
27 /*
28  * Test if memory at offset offset matches memory at begin of DRAM
29  */
30 bool mctl_mem_matches(u32 offset)
31 {
32 	/* Try to write different values to RAM at two addresses */
33 	writel(0, CONFIG_SYS_SDRAM_BASE);
34 	writel(0xaa55aa55, (ulong)CONFIG_SYS_SDRAM_BASE + offset);
35 	dsb();
36 	/* Check if the same value is actually observed when reading back */
37 	return readl(CONFIG_SYS_SDRAM_BASE) ==
38 	       readl((ulong)CONFIG_SYS_SDRAM_BASE + offset);
39 }
40