[U-Boot] [PATCH v2 8/8] arm: socfpga: implement proper peripheral reset

[Marek Vasut]

On 2/22/19 8:42 PM, Simon Goldschmidt wrote:
> 
> 
> Am Fr., 22. Feb. 2019, 20:37 hat Marek Vasut <marex at denx.de
> <mailto:marex at denx.de>> geschrieben:
> 
>     On 2/22/19 8:10 PM, Simon Goldschmidt wrote:
>     >
>     >
>     > Am Fr., 22. Feb. 2019, 18:34 hat Marek Vasut <marex at denx.de
>     <mailto:marex at denx.de>
>     > <mailto:marex at denx.de <mailto:marex at denx.de>>> geschrieben:
>     >
>     >     On 2/22/19 7:35 AM, Simon Goldschmidt wrote:
>     >     > On Thu, Feb 21, 2019 at 10:56 PM Marek Vasut <marex at denx.de
>     <mailto:marex at denx.de>
>     >     <mailto:marex at denx.de <mailto:marex at denx.de>>> wrote:
>     >     >>
>     >     >> On 2/21/19 10:43 PM, Simon Goldschmidt wrote:
>     >     >>> This commit removes ad-hoc reset handling for peripheral
>     resets
>     >     from SPL
>     >     >>> for socfpga gen5.
>     >     >>>
>     >     >>> This is done because as U-Boot drivers support reset
>     handling by
>     >     now.
>     >     >>>
>     >     >>> Signed-off-by: Simon Goldschmidt
>     >     <simon.k.r.goldschmidt at gmail.com
>     <mailto:simon.k.r.goldschmidt at gmail.com>
>     >     <mailto:simon.k.r.goldschmidt at gmail.com
>     <mailto:simon.k.r.goldschmidt at gmail.com>>>
>     >     >>> ---
>     >     >>>
>     >     >>> Changes in v2:
>     >     >>> - removed Kconfig option OLD_SOCFPGA_KERNEL_COMPAT since
>     >     compatibility
>     >     >>>   now uses an environment variable
>     >     >>>
>     >     >>>  arch/arm/mach-socfpga/misc_gen5.c | 10 ----------
>     >     >>>  arch/arm/mach-socfpga/spl_gen5.c  | 10 ----------
>     >     >>>  2 files changed, 20 deletions(-)
>     >     >>>
>     >     >>> diff --git a/arch/arm/mach-socfpga/misc_gen5.c
>     >     b/arch/arm/mach-socfpga/misc_gen5.c
>     >     >>> index 6e11ba6cb2..9865f5b5b1 100644
>     >     >>> --- a/arch/arm/mach-socfpga/misc_gen5.c
>     >     >>> +++ b/arch/arm/mach-socfpga/misc_gen5.c
>     >     >>> @@ -201,16 +201,6 @@ int arch_early_init_r(void)
>     >     >>>       /* Add device descriptor to FPGA device table */
>     >     >>>       socfpga_fpga_add(&altera_fpga[0]);
>     >     >>>
>     >     >>> -#ifdef CONFIG_DESIGNWARE_SPI
>     >     >>> -     /* Get Designware SPI controller out of reset */
>     >     >>> -     socfpga_per_reset(SOCFPGA_RESET(SPIM0), 0);
>     >     >>> -     socfpga_per_reset(SOCFPGA_RESET(SPIM1), 0);
>     >     >>> -#endif
>     >     >>> -
>     >     >>> -#ifdef CONFIG_NAND_DENALI
>     >     >>> -     socfpga_per_reset(SOCFPGA_RESET(NAND), 0);
>     >     >>> -#endif
>     >     >>> -
>     >     >>>       return 0;
>     >     >>>  }
>     >     >>>
>     >     >>> diff --git a/arch/arm/mach-socfpga/spl_gen5.c
>     >     b/arch/arm/mach-socfpga/spl_gen5.c
>     >     >>> index 1bff8cbfcf..e1e65261eb 100644
>     >     >>> --- a/arch/arm/mach-socfpga/spl_gen5.c
>     >     >>> +++ b/arch/arm/mach-socfpga/spl_gen5.c
>     >     >>> @@ -36,16 +36,12 @@ u32 spl_boot_device(void)
>     >     >>>               return BOOT_DEVICE_RAM;
>     >     >>>       case 0x2:       /* NAND Flash (1.8V) */
>     >     >>>       case 0x3:       /* NAND Flash (3.0V) */
>     >     >>> -             socfpga_per_reset(SOCFPGA_RESET(NAND), 0);
>     >     >>>               return BOOT_DEVICE_NAND;
>     >     >>>       case 0x4:       /* SD/MMC External Transceiver (1.8V) */
>     >     >>>       case 0x5:       /* SD/MMC Internal Transceiver (3.0V) */
>     >     >>> -             socfpga_per_reset(SOCFPGA_RESET(SDMMC), 0);
>     >     >>> -             socfpga_per_reset(SOCFPGA_RESET(DMA), 0);
>     >     >>>               return BOOT_DEVICE_MMC1;
>     >     >>>       case 0x6:       /* QSPI Flash (1.8V) */
>     >     >>>       case 0x7:       /* QSPI Flash (3.0V) */
>     >     >>> -             socfpga_per_reset(SOCFPGA_RESET(QSPI), 0);
>     >     >>>               return BOOT_DEVICE_SPI;
>     >     >>>       default:
>     >     >>>               printf("Invalid boot device (bsel=%08x)!\n",
>     bsel);
>     >     >>> @@ -99,9 +95,7 @@ void board_init_f(ulong dummy)
>     >     >>>               socfpga_bridges_reset(1);
>     >     >>>       }
>     >     >>>
>     >     >>> -     socfpga_per_reset(SOCFPGA_RESET(UART0), 0);
>     >     >>>       socfpga_per_reset(SOCFPGA_RESET(OSC1TIMER0), 0);
>     >     >>> -
>     >     >>>       timer_init();
>     >     >>>
>     >     >>>       debug("Reconfigure Clock Manager\n");
>     >     >>> @@ -123,10 +117,6 @@ void board_init_f(ulong dummy)
>     >     >>>       sysmgr_pinmux_init();
>     >     >>>       sysmgr_config_warmrstcfgio(0);
>     >     >>>
>     >     >>> -     /* De-assert reset for peripherals and bridges based on
>     >     handoff */
>     >     >>> -     reset_deassert_peripherals_handoff();
>     >     >>> -     socfpga_bridges_reset(0);
>     >     >
>     >     > I just saw that this line might have unwanted side effects
>     in that
>     >     it does
>     >     > not write the enabled bridges bitmask to the 'iswgrp_handoff'
>     >     registers.
>     >     > So the 'bridge enable' command might not work.
>     >     >
>     >     > This whole handoff thing looks somewhat broken to me anyway: the
>     >     > original Altera U-Boot did it because it obeyed Quartus output,
>     >     while we
>     >     > now just always write a constant bitmask here (see
>     >     socfpga_bridges_reset()).
>     >     >
>     >     > Regards,
>     >     > Simon
>     >
>     >     Might make sense to finally clean it up ?
>     >
>     >
>     > Yeah, well the problem is that for some things, handoff from
>     Quartus is
>     > required while for other things, devicetree information like it is now
>     > is enough.
> 
>     Might be just about the right time to convert quartus handoff files
>     to DT ?
> 
> 
> That would be great: I do have a use case where the pin description
> should be changeable after SPL.

Well, we don't have the pin control documentation, so unless we
"observe" what quartus generates real hard ...

> But that again would require more time than I currently have... :-(

Right, I'm not asking you to do it to get this series in.

-- 
Best regards,
Marek Vasut