ArmPlatformPkg/Drivers/PL35xSmc/InitializeSMC.S

   1 #
   2 #  Copyright (c) 2011, ARM Limited. All rights reserved.
   3 #
   4 #  This program and the accompanying materials
   5 #  are licensed and made available under the terms and conditions of the BSD License
   6 #  which accompanies this distribution.  The full text of the license may be found at
   7 #  http:#opensource.org/licenses/bsd-license.php
   8 #
   9 #  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  10 #  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  11 #
  12 #
  13
  14 #include <AsmMacroIoLib.h>
  15 #include <Library/PcdLib.h>
  16 #include <AutoGen.h>
  17 #include <Drivers/PL35xSmc.h>
  18
  19 .text
  20
  21 #Maintain 8 byte alignment
  22 .align 3
  23
  24 GCC_ASM_EXPORT(PL35xSmcInitialize)
  25
  26 // IN r1 Smc Base Address
  27 // IN r2 Smc Configuration Start Address
  28 // IN r3 Smc Configuration End Address
  29 // NOTE: This code is been called before any stack has been setup. It means some registers
  30 //       could be overwritten (case of 'r0')
  31 ASM_PFX(PL35xSmcInitialize):
  32   // While (SmcConfigurationStart < SmcConfigurationEnd)
  33   cmp   r2, r3
  34   blxge lr
  35
  36   // Write to set_cycle register(holding register for NOR 1 cycle register or NAND cycle register)
  37   ldr   r0, [r2, #0x4]
  38   str   r0, [r1, #PL350_SMC_SET_CYCLES_OFFSET]
  39
  40   // Write to set_opmode register(holding register for NOR 1 opomode register or NAND opmode register)
  41   ldr   r0, [r2, #0x8]
  42   str   r0, [r1, #PL350_SMC_SET_OPMODE_OFFSET]
  43
  44   // Write to direct_cmd register so that the NOR 1 registers(set-cycles and opmode) are updated with holding registers
  45   ldr   r0, =PL350_SMC_DIRECT_CMD_ADDR_CMD_UPDATE
  46   ldr   r4, [r2, #0x0]
  47   orr   r0, r0, r4
  48   str   r0, [r1, #PL350_SMC_DIRECT_CMD_OFFSET]
  49
  50   add   r2, #0xC
  51   b     ASM_PFX(PL350SmcInitialize)
  52
  53 ASM_FUNCTION_REMOVE_IF_UNREFERENCED