1 /*
2  * (C) Copyright 2014
3  * Texas Instruments, <www.ti.com>
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 #ifndef _TI_COMMON_SYS_PROTO_H_
8 #define _TI_COMMON_SYS_PROTO_H_
9 
10 DECLARE_GLOBAL_DATA_PTR;
11 
12 #ifdef CONFIG_ARCH_OMAP2PLUS
13 #define TI_ARMV7_DRAM_ADDR_SPACE_START	0x80000000
14 #define TI_ARMV7_DRAM_ADDR_SPACE_END	0xFFFFFFFF
15 
16 #define OMAP_INIT_CONTEXT_SPL			0
17 #define OMAP_INIT_CONTEXT_UBOOT_FROM_NOR	1
18 #define OMAP_INIT_CONTEXT_UBOOT_AFTER_SPL	2
19 #define OMAP_INIT_CONTEXT_UBOOT_AFTER_CH	3
20 
21 static inline u32 running_from_sdram(void)
22 {
23 	u32 pc;
24 	asm volatile ("mov %0, pc" : "=r" (pc));
25 	return ((pc >= TI_ARMV7_DRAM_ADDR_SPACE_START) &&
26 	    (pc < TI_ARMV7_DRAM_ADDR_SPACE_END));
27 }
28 
29 static inline u8 uboot_loaded_by_spl(void)
30 {
31 	/*
32 	 * u-boot can be running from sdram either because of configuration
33 	 * Header or by SPL. If because of CH, then the romcode sets the
34 	 * CHSETTINGS executed bit to true in the boot parameter structure that
35 	 * it passes to the bootloader.This parameter is stored in the ch_flags
36 	 * variable by both SPL and u-boot.Check out for CHSETTINGS, which is a
37 	 * mandatory section if CH is present.
38 	 */
39 	if (gd->arch.omap_ch_flags & CH_FLAGS_CHSETTINGS)
40 		return 0;
41 	else
42 		return running_from_sdram();
43 }
44 
45 /*
46  * The basic hardware init of OMAP(s_init()) can happen in 4
47  * different contexts:
48  *  1. SPL running from SRAM
49  *  2. U-Boot running from FLASH
50  *  3. Non-XIP U-Boot loaded to SDRAM by SPL
51  *  4. Non-XIP U-Boot loaded to SDRAM by ROM code using the
52  *     Configuration Header feature
53  *
54  * This function finds this context.
55  * Defining as inline may help in compiling out unused functions in SPL
56  */
57 static inline u32 omap_hw_init_context(void)
58 {
59 #ifdef CONFIG_SPL_BUILD
60 	return OMAP_INIT_CONTEXT_SPL;
61 #else
62 	if (uboot_loaded_by_spl())
63 		return OMAP_INIT_CONTEXT_UBOOT_AFTER_SPL;
64 	else if (running_from_sdram())
65 		return OMAP_INIT_CONTEXT_UBOOT_AFTER_CH;
66 	else
67 		return OMAP_INIT_CONTEXT_UBOOT_FROM_NOR;
68 #endif
69 }
70 #endif
71 
72 #endif
73