arch/arm/mach-rockchip/rk3188-board-tpl.c

   1 /*
   2  * (C) Copyright 2015 Google, Inc
   3  *
   4  * SPDX-License-Identifier:     GPL-2.0+
   5  */
   6
   7 #include <common.h>
   8 #include <debug_uart.h>
   9 #include <spl.h>
  10 #include <asm/io.h>
  11 #include <asm/arch/bootrom.h>
  12 #include <asm/arch/pmu_rk3188.h>
  13
  14 DECLARE_GLOBAL_DATA_PTR;
  15
  16 /* track how often we were entered */
  17 static int rk3188_num_entries __attribute__ ((section(".data")));
  18
  19 #define PMU_BASE        0x20004000
  20 #define SPL_ENTRY       0x10080C00
  21
  22 static void jump_to_spl(void)
  23 {
  24         typedef void __noreturn (*image_entry_noargs_t)(void);
  25
  26         struct rk3188_pmu * const pmu = (void *)PMU_BASE;
  27         image_entry_noargs_t tpl_entry =
  28                 (image_entry_noargs_t)(unsigned long)SPL_ENTRY;
  29
  30         /* Store the SAVE_SP_ADDR in a location shared with SPL. */
  31         writel(SAVE_SP_ADDR, &pmu->sys_reg[2]);
  32         tpl_entry();
  33 }
  34
  35 void board_init_f(ulong dummy)
  36 {
  37         /* Example code showing how to enable the debug UART on RK3188 */
  38 #ifdef EARLY_UART
  39 #include <asm/arch/grf_rk3188.h>
  40         /* Enable early UART on the RK3188 */
  41 #define GRF_BASE        0x20008000
  42         struct rk3188_grf * const grf = (void *)GRF_BASE;
  43
  44         rk_clrsetreg(&grf->gpio1b_iomux,
  45                      GPIO1B1_MASK << GPIO1B1_SHIFT |
  46                      GPIO1B0_MASK << GPIO1B0_SHIFT,
  47                      GPIO1B1_UART2_SOUT << GPIO1B1_SHIFT |
  48                      GPIO1B0_UART2_SIN << GPIO1B0_SHIFT);
  49         /*
  50          * Debug UART can be used from here if required:
  51          *
  52          * debug_uart_init();
  53          * printch('a');
  54          * printhex8(0x1234);
  55          * printascii("string");
  56          */
  57         debug_uart_init();
  58
  59         printch('t');
  60         printch('p');
  61         printch('l');
  62         printch('-');
  63         printch(rk3188_num_entries + 1 + '0');
  64         printch('\n');
  65 #endif
  66
  67         rk3188_num_entries++;
  68
  69         if (rk3188_num_entries == 1) {
  70                 /*
  71                  * The original loader did some very basic integrity
  72                  * checking at this point, but the remaining few bytes
  73                  * could be used for any improvement making sense
  74                  * really early on.
  75                  */
  76
  77                 back_to_bootrom();
  78         } else {
  79                 /*
  80                  * TPL part of the loader should now wait for us
  81                  * at offset 0xC00 in the sram. Should never return
  82                  * from there.
  83                  */
  84                 jump_to_spl();
  85         }
  86 }