Re: [PATCH v10 17/19] ARM: tegra: Add EMC OPP properties to Tegra20 device-trees

Krzysztof Kozlowski
2020-12-05T18:22:05Z

On Fri, Dec 04, 2020 at 04:54:55PM +0100, Thierry Reding wrote:
> On Tue, Dec 01, 2020 at 01:57:44AM +0300, Dmitry Osipenko wrote:
> > 01.12.2020 00:17, Jon Hunter пишет:
> > > Hi Dmitry,
> > >
> > > On 23/11/2020 00:27, Dmitry Osipenko wrote:
> > >> Add EMC OPP DVFS tables and update board device-trees by removing
> > >> unsupported OPPs.
> > >>
> > >> Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
> > > This change is generating the following warning on Tegra20 Ventana
> > > and prevents the EMC from probing ...
> > >
> > > [ 2.485711] tegra20-emc 7000f400.memory-controller: device-tree doesn't have memory timings
> > > [ 2.499386] tegra20-emc 7000f400.memory-controller: 32bit DRAM bus
> > > [ 2.505810] ------------[ cut here ]------------
> > > [ 2.510511] WARNING: CPU: 0 PID: 1 at /local/workdir/tegra/mlt-linux_next/kernel/drivers/opp/of.c:875 _of_add_opp_table_v2+0x598/0x61c
> > > [ 2.529746] Modules linked in:
> > > [ 2.540140] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.10.0-rc5-next-20201130 #1
> > > [ 2.554606] Hardware name: NVIDIA Tegra SoC (Flattened Device Tree)
> > > [ 2.560892] [<c011136c>] (unwind_backtrace) from [<c010bb60>] (show_stack+0x10/0x14)
> > > [ 2.568640] [<c010bb60>] (show_stack) from [<c0bcee54>] (dump_stack+0xc8/0xdc)
> > > [ 2.575866] [<c0bcee54>] (dump_stack) from [<c01235dc>] (__warn+0x104/0x108)
> > > [ 2.582912] [<c01235dc>] (__warn) from [<c0123690>] (warn_slowpath_fmt+0xb0/0xb8)
> > > [ 2.590397] [<c0123690>] (warn_slowpath_fmt) from [<c0825ad0>] (_of_add_opp_table_v2+0x598/0x61c)
> > > [ 2.599269] [<c0825ad0>] (_of_add_opp_table_v2) from [<c0825b90>] (dev_pm_opp_of_add_table+0x3c/0x1a0)
> > > [ 2.608582] [<c0825b90>] (dev_pm_opp_of_add_table) from [<c087b774>] (tegra_emc_probe+0x478/0x940)
> > > [ 2.617548] [<c087b774>] (tegra_emc_probe) from [<c0654398>] (platform_drv_probe+0x48/0x98)
> > > [ 2.625899] [<c0654398>] (platform_drv_probe) from [<c0652238>] (really_probe+0x218/0x3b8)
> > > [ 2.634162] [<c0652238>] (really_probe) from [<c0652540>] (driver_probe_device+0x5c/0xb4)
> > > [ 2.642338] [<c0652540>] (driver_probe_device) from [<c0652740>] (device_driver_attach+0x58/0x60)
> > > [ 2.651208] [<c0652740>] (device_driver_attach) from [<c06527c8>] (__driver_attach+0x80/0xbc)
> > > [ 2.659730] [<c06527c8>] (__driver_attach) from [<c0650610>] (bus_for_each_dev+0x74/0xb4)
> > > [ 2.667905] [<c0650610>] (bus_for_each_dev) from [<c06515f8>] (bus_add_driver+0x164/0x1e8)
> > > [ 2.676168] [<c06515f8>] (bus_add_driver) from [<c06532a8>] (driver_register+0x7c/0x114)
> > > [ 2.684259] [<c06532a8>] (driver_register) from [<c0102208>] (do_one_initcall+0x54/0x2b0)
> > > [ 2.692441] [<c0102208>] (do_one_initcall) from [<c10010cc>] (kernel_init_freeable+0x1a4/0x1f4)
> > > [ 2.701145] [<c10010cc>] (kernel_init_freeable) from [<c0bd4510>] (kernel_init+0x8/0x118)
> > > [ 2.709321] [<c0bd4510>] (kernel_init) from [<c01001b0>] (ret_from_fork+0x14/0x24)
> > > [ 2.716885] Exception stack(0xc1501fb0 to 0xc1501ff8)
> > > [ 2.721933] 1fa0: 00000000 00000000 00000000 00000000
> > > [ 2.730106] 1fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > [ 2.738278] 1fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > [ 2.751940] ---[ end trace 61e3b76deca27ef3 ]---
> > >
> > >
> > > Cheers
> > > Jon
> > >
> >
> > Hello Jon,
> >
> > That is harmless and expected to happen because the patch "memory:
> > tegra20: Support hardware versioning and clean up OPP table
> > initialization" isn't applied yet, while Thierry already applied the DT
> > patches from this v10.
>
> Hmm... that's new. Since when are device tree additions expected to
> cause these kinds of splats?

It looks rather as inaccurate message, but except the message itself,
no functionality was lost.

> Anyway, I did apply these because I had seen at least some of the memory
> controller driver patches appear in linux-next and hence had assumed
> that the whole series had gone in, not realizing there was anything left
> to do.
>
> Krzysztof, what's your schedule for the memory controller tree? My
> recollection is that this will feed into ARM SoC, so if the -rc6 dead-
> line applies like it does for platforms, then I may need to revert the
> DT patch that causes this so that we don't have to drag this along
> through all of the release cycle. If there's still time for you to send
> that PR, perhaps we can get the remainder of the Tegra interconnect
> series merged for v5.11 as well?

I was waiting for last acks from Rob and you and actually planned to
merge everything this week (weekend at the latest). Indeed it slightly
slipped away... the v11 was reposted late.

It could still make till v5.11, if I send the PR now (still around 3
weeks before merge window).

However I saw now your comments for the patch 4/10 from v11. I'll take
patches 1-3 for now.

Best regards,
Krzysztof