On Wed, Oct 30, 2024 at 02:13:43PM +0100, Michal Simek wrote:
>
>
> On 10/29/24 19:58, Vasileios Amoiridis wrote:
> > From: Vasileios Amoiridis <vasileios.amoiri...@cern.ch>
> >
> > Add native support of the bootcount mechanism in the ZynqMP by utilising
> > internal
> > PMU registers. The Persistent Global Storage Registers of the Platform
> > Management
> > Unit can keep their value during reboot cycles unless there is a POR reset,
> > making
> > them appropriate for the bootcount mechanism.
> >
> > Signed-off-by: Vasileios Amoiridis <vasileios.amoiri...@cern.ch>
> > ---
> > drivers/bootcount/Kconfig | 4 ++++
> > drivers/bootcount/Makefile | 1 +
> > drivers/bootcount/bootcount_zynqmp.c | 28 ++++++++++++++++++++++++++++
> > 3 files changed, 33 insertions(+)
> > create mode 100644 drivers/bootcount/bootcount_zynqmp.c
> >
> > diff --git a/drivers/bootcount/Kconfig b/drivers/bootcount/Kconfig
> > index fa6d8e7128..95b6a9541a 100644
> > --- a/drivers/bootcount/Kconfig
> > +++ b/drivers/bootcount/Kconfig
> > @@ -82,6 +82,10 @@ config BOOTCOUNT_AT91
> > bool "Boot counter for Atmel AT91SAM9XE"
> > depends on AT91SAM9XE
> > +config BOOTCOUNT_ZYNQMP
> > + bool "Boot counter for Zynq UltraScale+ MPSoC"
> > + depends on ARCH_ZYNQMP
>
>
> help would help to also described where that count is stored.
>
Hi Michal,
thanks for the review. Indeed I could add it.
> And why not to have it under DM/U_BOOT_DRIVER?
> You don't need to create compatible string for it just instantiate it.
>
> Look at:
>
> U_BOOT_DRVINFO(soc_xilinx_zynqmp) = {
> .name = "soc_xilinx_zynqmp",
> };
>
I was not fully aware of this, I could try it. Just out of curiosity, is
this the new/prefered way of adding new drivers?
>
> > +
> > config DM_BOOTCOUNT
> > bool "Boot counter in a device-model device"
> > help
> > diff --git a/drivers/bootcount/Makefile b/drivers/bootcount/Makefile
> > index 245f879633..487adc1212 100644
> > --- a/drivers/bootcount/Makefile
> > +++ b/drivers/bootcount/Makefile
> > @@ -3,6 +3,7 @@
> > obj-$(CONFIG_BOOTCOUNT_GENERIC) += bootcount.o
> > obj-$(CONFIG_BOOTCOUNT_MEM) += bootcount.o
> > obj-$(CONFIG_BOOTCOUNT_AT91) += bootcount_at91.o
> > +obj-$(CONFIG_BOOTCOUNT_ZYNQMP) += bootcount_zynqmp.o
>
> please put it to the end of CONFIG_BOOTCOUNT to have it at least in correct
> location
>
> > obj-$(CONFIG_BOOTCOUNT_AM33XX) += bootcount_davinci.o
> > obj-$(CONFIG_BOOTCOUNT_RAM) += bootcount_ram.o
> > obj-$(CONFIG_BOOTCOUNT_ENV) += bootcount_env.o
> > diff --git a/drivers/bootcount/bootcount_zynqmp.c
> > b/drivers/bootcount/bootcount_zynqmp.c
> > new file mode 100644
> > index 0000000000..9bb801e188
> > --- /dev/null
> > +++ b/drivers/bootcount/bootcount_zynqmp.c
> > @@ -0,0 +1,28 @@
> > +// SPDX-License-Identifier: GPL-2.0-or-later
> > +// SPDX-FileCopyrightText: 2024 CERN (home.cern)
> > +
> > +#include <bootcount.h>
> > +#include <stdio.h>
> > +#include <zynqmp_firmware.h>
> > +
> > +#define PMU_PERS_GLOB_GEN_STORAGE0 0x00FFD80050
>
> In arch/arm/mach-zynqmp/include/mach/hardware.h
> there is already structure defined and gen_storage0 is there too.
> Please use it.
>
> Regarding this location. Exception in PMUFW is using this reg.
> It means at the end of day it is up to you if you want to use it or not.
>
In master branch (commit 5cca0e3f6e0ff17db92476235ea1bb9cd8cbc9eb) there
is no gen_storage0 in the structure pmu_regs, only gen_storage4 and
gen_storage6.
But in any case though, I don't use gen_storage0 which is the
Global General Storage 0 but the Persistent Global General Storage 0
which is in the in the offset 0x50 and is defined in [1]. According to
this document, only registers {4:7} are used by FSBL and other Xilinx
software products so from what I understand registers {0:3} are free to
use. If that's not the case, which one of them is free for use?
[1]:
https://docs.amd.com/r/en-US/ug1087-zynq-ultrascale-registers/PERS_GLOB_GEN_STORAGE0-PMU_GLOBAL-Register
> > +
> > +void bootcount_store(ulong a)
> > +{
> > + int ret;
> > +
> > + ret = zynqmp_mmio_write(PMU_PERS_GLOB_GEN_STORAGE0, 0xFF, a);
> > + if (ret)
> > + printf("Failed: mmio write\n");
> > +}
> > +
> > +ulong bootcount_load(void)
> > +{
> > + int ret;
> > + u32 val;
>
> as was said val should be initialized here too.
>
Yes indeed.
> > +
> > + ret = zynqmp_mmio_read(PMU_PERS_GLOB_GEN_STORAGE0, &val);
> > + if (ret)
> > + printf("Failed: mmio read\n");
> > + return val;
> > +}
>
> Anyway I expect this driver to be under DM that v2 will change.
>
> Thanks,
> Michal
>
>
>
Yes, I will try and come back to you in case I don't get something.
Thanks again for the review.
Cheers,
Vasilis
