[RESEND 0/3] rockchip: Fix RAM training on RK3399 based platforms (Rock Pi 4)

[Lee Jones]

On Wed, 28 Sep 2022, Michal Suchánek wrote:

> On Wed, Sep 28, 2022 at 10:26:35AM +0100, Lee Jones wrote:
> > On Fri, 09 Sep 2022, Kever Yang wrote:
> > 
> > > Hi Lee Jones,
> > > 
> > > On 2022/9/8 15:44, Lee Jones wrote:
> > > > On Thu, 11 Aug 2022, Lee Jones wrote:
> > > > 
> > > > > This set fixes several issues found on the Rock Pi 4.
> > > > > 
> > > > > For full context, please see this initial bug report:
> > > > > 
> > > > >   "There appear to be a number of issues with the Rockchip rk3399 DDR RAM
> > > > >    initialisation sequence in Mainline.  Specifically, I'm seeing
> > > > >    consistent failures on the Rock Pi 4+ during early boot.  A typical
> > > > >    failure looks something like this:
> > > > >      U-Boot TPL 2022.07-rc3-00005-g1b04a961c6 (May 25 2022 - 11:09:19)
> > > > >      Channel 0: LPDDR4, 50MHz
> > > > >      BW=32 Col=10 Bk=8 CS0 Row=16/15 CS=1 Die BW=16 Size=2048MB
> > > > >      Channel 1: col error
> > > > >      Cap error!
> > > > >      256B stride
> > > > >      lpddr4_set_rate: change freq to 400000000 mhz 0, 1
> > > > >      lpddr4_set_rate: change freq to 800000000 mhz 1, 0
> > > > >      Trying to boot from BOOTROM
> > > > >      Returning to boot ROM...
> > > > >    Even when the system boots to a terminal, which happens very
> > > > >    infrequently, the LPDDR4 RAM chip at Channel 1 can have conflicting
> > > > >    discovery information printed during TPL.  The following 3 lines were
> > > > >    printed during successive reboots using the same SD card with no
> > > > >    changes:
> > > > >      # Boot 1:
> > > > >      BW=32 Col=9 Bk=4 CS0 Row=16/15 CS=1 Die BW=16 Size=384MB
> > > > >      # Boot 2:
> > > > >      BW=32 Col=10 Bk=4 CS0 Row=16/15 CS=1 Die BW=16 Size=768MB
> > > > >      # Boot 3:
> > > > >      BW=32 Col=10 Bk=4 CS0 Row=15 CS=1 Die BW=16 Size=512MB
> > > > >    The story changes when I build the idbloader.img image with Rockchip's
> > > > >    TBL (?) binary blob [0].  With that built in, presumably in place of
> > > > >    the upstream TBL, both RAM chips are successfully enumerated and boot
> > > > >    succeeds with 100% success rate:
> > > > >      tools/mkimage -n rk3399 -T rksd -d \
> > > > >        rk3399_ddr_933MHz_v1.25.bin:spl/u-boot-spl.bin idbloader.img
> > > > >    Another thing that is very different between the 2 is the initial
> > > > >    frequency the LPDDR4 chips are clocked at.  Using the upstream TBL
> > > > >    version, the default is 50Mhz, which seems very low.  If using the
> > > > >    Rockchip supplied binary blob file, this is increased to a respectable
> > > > >    416MHz:
> > > > >      # Mainline
> > > > >      Channel 0: LPDDR4, 50MHz
> > > > >      # Rockchip TBL blob
> > > > >      Channel 0: LPDDR4,416MHz
> > > > >    One thing I did try was to load in the 400Mhz configuration settings
> > > > >    from drivers/ram/rockchip/sdram-rk3399-lpddr4-400.inc as the default
> > > > >    initial values, instead of the 50MHz default taken from
> > > > >    arch/arm/dts/rk3399-sdram-lpddr4-100.dtsi, but this failed in a number
> > > > >    of ways:
> > > > >      Setting clock: Freq: 400MHz (400000000)
> > > > >      Calling SDRAM init: 2 Channels
> > > > >      Starting SDRAM initialization...
> > > > >        mr5:0  mr12:0  mr14:0
> > > > >        Training failed for rank 2, ch 0 (ret: -22)
> > > > >        mr5:0  mr12:0  mr14:0
> > > > >        Training failed for rank 1, ch 0 (ret: -22)
> > > > >        mr5:0  mr12:0  mr14:0
> > > > >        Training failed for rank 2, ch 1 (ret: -22)
> > > > >        mr5:0  mr12:0  mr14:0
> > > > >        Training failed for rank 1, ch 1 (ret: -22)
> > > > >        Rank for Channel 1 is 0x0
> > > > >        Rank for Channel 0 is 0x0
> > > > >        Rank for Channel 1 is 0x0
> > > > >      sdram_init: LPDDR4 - 400MHz failed!
> > > > >      rk3399_dmc_init DRAM init failed -22
> > > > >    So my question is; does Rockchip, or anyone else for that matter, have
> > > > >    any plans on updating Mainline U-Boot with the upgraded/working LPDDR4
> > > > >    initialisation sequence?"
> > > > > 
> > > > > Lee Jones (3):
> > > > >    ram: rk3399: Fix .set_rate_index() error handling
> > > > >    ram: rk3399: Fix faulty frequency change reports
> > > > >    ram: rk3399: Conduct memory training at 400MHz
> > > > > 
> > > > >   drivers/ram/rockchip/sdram_rk3399.c | 38 +++++++++++++++++------------
> > > > >   1 file changed, 23 insertions(+), 15 deletions(-)
> > > > Looks as though we have all the Reviews we need.
> > > > 
> > > > Would someone be kind enough to merge these patches please?
> > > 
> > > Yes, I will merge this patch set soon.
> > 
> > Any luck with this Kever?
> 
> Merged in 337e92e79c95ffb8c0c6e7b4023c955c50fca018

That's great.

Is it not common practice to send out "applied" messages?

> HTH

Yes, thank you Michal.

-- 
Lee Jones [李琼斯]