arch/arm/include/asm/ti-common/sys_proto.h

   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