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