[PATCH] arm: mvebu: spl: Always fallback to BootROM boot method

[Pali Rohár]

On Tuesday 02 August 2022 15:13:13 Tony Dinh wrote:
> Hi Pali,
> 
> On Tue, Aug 2, 2022 at 3:00 PM Pali Rohár <pali at kernel.org> wrote:
> >
> > Hello! We have tested that A385 BootROM on Turris Omnia board is much
> > slower when reading proper U-Boot from SPI NOR than native SPL SPI
> > driver.
> >
> > If you have different test results on A385, could you check SPI speed
> > used by U-Boot? I think that CONFIG_SF_DEFAULT_SPEED should define it.
> > For Omnia we use CONFIG_SF_DEFAULT_SPEED=40000000. Also check value of
> > DT property spi-max-frequency. We have: spi-max-frequency = <40000000>;
> 
> It seems the spi-max-frequency = <50000000> in the DTS took precedence here?

I'm not sure. It is possible that config option has higher priority. Try
to set both values to same speed.

> #grep CONFIG_SF_DEFAULT_SPEED .config
> CONFIG_SF_DEFAULT_SPEED=1000000
> 
> #grep spi-max-frequency arch/arm/dts/armada-385-synology-ds116.dts
> spi-max-frequency = <50000000>;
> 
> Thanks,
> Tony
> 
> 
> > On Tuesday 02 August 2022 14:50:32 Tony Dinh wrote:
> > > Hi Pali,
> > >
> > > It works great!
> > >
> > > An observation: BootROM boot method is a lot faster than SPL SPI
> > > driver method on this Armada 385 board. The BootROM took a fraction of
> > > a second to load the u-boot image. SPL SPI driver took a few seconds
> > > to load. Perhaps the SPI flash speed vs some probing code in SPL SPI
> > > driver? I also include the boot log after signature.
> > >
> > > Tested-by: Tony Dinh <mibodhi at gmail.com>
> > >
> > > Thanks,
> > > Tony
> > >
> > > <Begin boot log>
> > >
> > > BootROM - 1.73
> > > Booting from SPI flash
> > >
> > > U-Boot SPL 2022.10-rc1-00212-g80e1491a03-dirty (Aug 02 2022 - 14:07:12 -0700)
> > > High speed PHY - Version: 2.0
> > > Detected Device ID 6820
> > > board SerDes lanes topology details:
> > >  | Lane # | Speed |  Type       |
> > >  --------------------------------
> > >  |   0    |   0   | SGMII0 |
> > >  |   1    |   6   | SATA0 |
> > >  |   4    |   5   | USB3 HOST0 |
> > >  |   5    |   5   | USB3 HOST1 |
> > >  --------------------------------
> > > High speed PHY - Ended Successfully
> > > mv_ddr: 14.0.0
> > > DDR3 Training Sequence - Switching XBAR Window to FastPath Window
> > > mv_ddr: completed successfully
> > > Trying to boot from SPI
> > > Invalid bus 0 (err=-19)
> > > SPI probe failed.
> > > Trying to boot from BOOTROM
> > > Returning to BootROM (return address 0xffff05c4)...
> > > BootROM: Image checksum verification PASSED
> > >
> > >
> > > U-Boot 2022.10-rc1-00212-g80e1491a03-dirty (Aug 02 2022 - 14:07:12 -0700)
> > > Synology DS116
> > >
> > > SoC:   MV88F6820-A0 at 1866 MHz
> > > DRAM:  1 GiB (933 MHz, 32-bit, ECC not enabled)
> > > Core:  41 devices, 18 uclasses, devicetree: separate
> > > MMC:
> > > Loading Environment from SPIFlash... SF: Detected mx25l6405d with page
> > > size 256 Bytes, erase size 4 KiB, total 8 MiB
> > > OK
> > > Model: Synology DS116
> > > Board: Synology DS116
> > > Net:   eth0: ethernet at 70000
> > > Hit any key to stop autoboot:  0
> > >
> > > <End boot log>
> > >
> > >
> > > On Tue, Aug 2, 2022 at 2:55 AM Pali Rohár <pali at kernel.org> wrote:
> > > >
> > > > BootROM boot method should always work so always add it as fallback method
> > > > to spl_boot_list. In case U-Boot SPI driver fails it is better to try using
> > > > BootROM than hanging as by default only one boot method is specified.
> > > >
> > > > Signed-off-by: Pali Rohár <pali at kernel.org>
> > > > ---
> > > >  arch/arm/mach-mvebu/spl.c | 7 +++++++
> > > >  1 file changed, 7 insertions(+)
> > > >
> > > > diff --git a/arch/arm/mach-mvebu/spl.c b/arch/arm/mach-mvebu/spl.c
> > > > index 13c99913c380..bfcba2e73bab 100644
> > > > --- a/arch/arm/mach-mvebu/spl.c
> > > > +++ b/arch/arm/mach-mvebu/spl.c
> > > > @@ -271,6 +271,13 @@ u32 spl_boot_device(void)
> > > >         }
> > > >  }
> > > >
> > > > +void board_boot_order(u32 *spl_boot_list)
> > > > +{
> > > > +       spl_boot_list[0] = spl_boot_device();
> > > > +       if (spl_boot_list[0] != BOOT_DEVICE_BOOTROM)
> > > > +               spl_boot_list[1] = BOOT_DEVICE_BOOTROM;
> > > > +}
> > > > +
> > > >  #else
> > > >
> > > >  u32 spl_boot_device(void)
> > > > --
> > > > 2.20.1
> > > >