[PATCH v2 0/2] arm: stm32mp1: activate data cache in SPL and before relocation

[Patrick Delaunay]

V2 after first feedbacks of the previous patch
"arm: stm32mp1: activate data cache in SPL and before relocation"
http://patchwork.ozlabs.org/patch/1263815/

This new serie depends on the ARM cache serie:
http://patchwork.ozlabs.org/project/uboot/list/?series=168378

I move tlb in .data section and simplify the implementation by reusing
the default weak function dram_bank_mmu_setup() for MMU configuration
and mmu_set_region_dcache_behaviour() to setup the specific behavior.

I also activate data cache on DDR for SPL.

For information the gain of the second patch is limited (few ms) for boot
from SDCARD: the SDMMC IP use internal DMA and data cache on DDR is
not really used.

Gain should be better for other boot use-case.

Example of bootstage report on STM32MP157C-DK2, boot from SD card.

1/ For trusted boot chain with TF-A

a) Before

    STM32MP> bootstage report
    Timer summary in microseconds (9 records):
           Mark    Elapsed  Stage
              0          0  reset
        583,290    583,290  board_init_f
      2,348,898  1,765,608  board_init_r
      2,664,580    315,682  id=64
      2,704,027     39,447  id=65
      2,704,729        702  main_loop
      5,563,519  2,858,790  id=175

    Accumulated time:
                    41,696  dm_r
                   615,561  dm_f

b) After the serie

    STM32MP> bootstage report
    Timer summary in microseconds (9 records):
           Mark    Elapsed  Stage
              0          0  reset
        583,401    583,401  board_init_f
        727,725    144,324  board_init_r
      1,043,362    315,637  id=64
      1,082,806     39,444  id=65
      1,083,507        701  main_loop
      3,680,827  2,597,320  id=175

    Accumulated time:
                    36,047  dm_f
                    41,718  dm_r

2/ And for the basic boot chain with SPL

a) Before:

    STM32MP> bootstage report
    Timer summary in microseconds (12 records):
           Mark    Elapsed  Stage
              0          0  reset
        195,613    195,613  SPL
        837,867    642,254  end SPL
        840,117      2,250  board_init_f
      2,739,639  1,899,522  board_init_r
      3,066,815    327,176  id=64
      3,103,377     36,562  id=65
      3,104,078        701  main_loop
      3,142,171     38,093  id=175

    Accumulated time:
                    38,124  dm_spl
                    41,956  dm_r
                   648,861  dm_f

b) After the serie

    STM32MP> bootstage report
    Timer summary in microseconds (12 records):
           Mark    Elapsed  Stage
              0          0  reset
        195,859    195,859  SPL
        330,190    134,331  end SPL
        332,408      2,218  board_init_f
        482,688    150,280  board_init_r
        808,694    326,006  id=64
        845,029     36,335  id=65
        845,730        701  main_loop
      3,281,876  2,436,146  id=175

    Accumulated time:
                     3,169  dm_spl
                    36,041  dm_f
                    41,701  dm_r

    STM32MP> bootstage report
    Timer summary in microseconds (12 records):
           Mark    Elapsed  Stage
              0          0  reset
        211,036    211,036  SPL
        343,393    132,357  end SPL
        345,645      2,252  board_init_f
        496,596    150,951  board_init_r
        822,256    325,660  id=64
        858,451     36,195  id=65
        859,153        702  main_loop
      3,414,706  2,555,553  id=175

    Accumulated time:
                     3,132  dm_spl
                    36,005  dm_f
                    41,695  dm_r


Changes in v2:
- create a new function early_enable_caches
- use TLB in .init section
- use the default weak dram_bank_mmu_setup() and
  use mmu_set_region_dcache_behaviour() to setup
  the early MMU configuration
- enable data cache on DDR in SPL, after DDR controller initialization
- new

Patrick Delaunay (2):
  arm: stm32mp: activate data cache in SPL and before relocation
  arm: stm32mp: activate data cache on DDR in SPL

 arch/arm/mach-stm32mp/cpu.c | 43 ++++++++++++++++++++++++++++++++++++-
 arch/arm/mach-stm32mp/spl.c | 21 ++++++++++++++++++
 2 files changed, 63 insertions(+), 1 deletion(-)

-- 
2.17.1