[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <DB6PR0402MB27605640244CE751317E6DE888720@DB6PR0402MB2760.eurprd04.prod.outlook.com>
Date: Mon, 27 Jul 2020 09:18:31 +0000
From: Peng Fan <peng.fan@....com>
To: Oleksij Rempel <o.rempel@...gutronix.de>
CC: "bjorn.andersson@...aro.org" <bjorn.andersson@...aro.org>,
"mathieu.poirier@...aro.org" <mathieu.poirier@...aro.org>,
"robh+dt@...nel.org" <robh+dt@...nel.org>,
"devicetree@...r.kernel.org" <devicetree@...r.kernel.org>,
"festevam@...il.com" <festevam@...il.com>,
"s.hauer@...gutronix.de" <s.hauer@...gutronix.de>,
"linux-remoteproc@...r.kernel.org" <linux-remoteproc@...r.kernel.org>,
"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
dl-linux-imx <linux-imx@....com>,
"kernel@...gutronix.de" <kernel@...gutronix.de>,
"shawnguo@...nel.org" <shawnguo@...nel.org>,
"linux-arm-kernel@...ts.infradead.org"
<linux-arm-kernel@...ts.infradead.org>
Subject: RE: [PATCH 00/10] remoteproc: imx_rproc: support iMX8M and early boot
> Subject: Re: [PATCH 00/10] remoteproc: imx_rproc: support iMX8M and early
> boot
>
> On Mon, Jul 27, 2020 at 06:44:32AM +0000, Peng Fan wrote:
> > Hi Oleksij,
> >
> > > Subject: Re: [PATCH 00/10] remoteproc: imx_rproc: support iMX8M and
> > > early boot
> > >
> > > Hi,
> > >
> > > On Fri, Jul 24, 2020 at 04:08:03PM +0800, Peng Fan wrote:
> > > > This patchset is to support i.MX8MQ/M coproc booted before linux.
> > > > Since i.MX8MQ/M was not supported, several patches are needed to
> > > > first support the platform, then support early boot case.
> > > >
> > > > I intended to included i.MX8QM/QXP, but that would introduce a
> > > > large patchset, so not included. But the clk/syscon optional patch
> > > > for i.MX8QM/QXP was still kept here to avoid rebase error.
> > >
> > > Thank you for your work.
> > >
> > > Can you please provide more information about big picture of this work.
> > >
> > > If I see it correctly, we have here support for i.MX8MM, which seems
> > > to be able to fully control Cortex M4 (enable CPU core, etc...).
> >
> > Yes.
>
> In this case, I would recommend to mainline the i.MX8MM part
> first/separately.
Only the last patch is to support earlyboot, all others is imx8mm part.
>
> > >
> > > And other case, where remoteproc is running on application processor
> > > and can't or should not touch M4 (i.MX7ULP, i.MX8QM/QXP..). Since M4
> > > provides some functionality, you are trying to reuse remoteproc
> > > framework to get resource table present in ELF header and to
> > > dynamically load things. For some reasons this header provides more
> > > information then needed, so you are changing the ELF parser in the kernel
> to workaround it.
> >
> > Not exactly.
> >
> > For i.MX8MM, we support two cases. M4 kicked by U-Boot, M4 kicked by
> Linux remoteproc.
> > For i.MX8QM/QXP, the typical usecase is M4 kicked by SCFW, but we will
> > also add M4 kicked by Linux remoteproc.
> > For i.MX7ULP, I would only support M4 dual boot case, M4 control
> everything.
>
> From current state of discussion, i'm not sure what role plays remoteproc in
> the scenario where M4 is started before linux. Especially if we are not using
> resource table.
We are using resource table from an address, not in elf file.
This is the new feature in Linux-next to support coproc booted early.
>
> > The reason the change the elf parser is that when M4 elf is loaded by
> > Linux remoteproc, It use memset to clear area.
>
> The use of memset, depends on ELF format. Fix/change the linker script on
> your firmware and memset will be never called.
>
> > However we use ioremap, memset on ARM64 will report crash to device
> > nGnRE memory. And we could not use ioremap_wc to TCM area, since it
> > could have data correctly written into TCM.
>
> I have strong feeling, that we are talking about badly or not properly
> formatted ELF binary. I would prefer to double check it, before we will apply
> fixes on wrong place.
>
> > Maintainer not wanna to drop memset in common code, and TI guys
> > suggest add i.MX specific elf stuff. So I add elf handler in i.MX code.
>
> I think, removing memset may damage current users of imx_rproc driver.
> Since, like I said: the use of memset depends on ELF format.
In my elf file, the last PT_LOAD contains data/bss/heap/stack. I'll check
with our MCU guys, we only need the specific data loaded.
Elf file type is EXEC (Executable file)
Entry point 0x1ffe0355
There are 3 program headers, starting at offset 52
Program Headers:
Type Offset VirtAddr PhysAddr FileSiz MemSiz Flg Align
LOAD 0x010000 0x1ffe0000 0x1ffe0000 0x00240 0x00240 R 0x10000
LOAD 0x010240 0x1ffe0240 0x1ffe0240 0x03e90 0x03e90 RWE 0x10000
LOAD 0x020000 0x20000000 0x1ffe40d0 0x00068 0x0ad00 RW 0x10000
Section to Segment mapping:
Segment Sections...
00 .interrupts
01 .resource_table .text .ARM .init_array .fini_array
02 .data .bss .heap .stack
Thanks,
Peng.
>
> > Thanks,
> > Peng.
> >
> > >
> > > Correct?
> > >
> > > > Peng Fan (10):
> > > > dt-bindings: remoteproc: imx_rproc: add i.MX8MQ/M
> > > > remoteproc: imx_rproc: correct err message
> > > > remoteproc: imx: use devm_ioremap
> > > > remoteproc: imx_rproc: make syscon optional
> > > > remoteproc: imx_rproc: make clk optional
> > > > remoteproc: imx_rproc: add load hook
> > > > remoteproc: imx_rproc: add i.MX specific parse fw hook
> > > > remoteproc: imx_rproc: support i.MX8MQ/M
> > > > remoteproc: imx_proc: enable virtio/mailbox
> > > > remoteproc: imx_rproc: support coproc booting before Linux
> > > >
> > > > .../devicetree/bindings/remoteproc/imx-rproc.txt | 3 +
> > > > drivers/remoteproc/imx_rproc.c | 409
> > > ++++++++++++++++++++-
> > > > 2 files changed, 401 insertions(+), 11 deletions(-)
> > > >
> > > > --
> > > > 2.16.4
> > > >
> > > >
> > > > _______________________________________________
> > > > linux-arm-kernel mailing list
> > > > linux-arm-kernel@...ts.infradead.org
> > > > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
> > > >
> > >
> > > --
> > > Pengutronix e.K. |
> > > |
> > > Steuerwalder Str. 21 |
> > > http://www.pengutronix.de/ |
> > > 31137 Hildesheim, Germany | Phone:
> > > +49-5121-206917-0 |
> > > Amtsgericht Hildesheim, HRA 2686 | Fax:
> > > +49-5121-206917-5555 |
>
> --
> Pengutronix e.K. |
> |
> Steuerwalder Str. 21 |
> http://www.pengutronix.de/ |
> 31137 Hildesheim, Germany | Phone:
> +49-5121-206917-0 |
> Amtsgericht Hildesheim, HRA 2686 | Fax:
> +49-5121-206917-5555 |
Powered by blists - more mailing lists