[PATCH v2 1/1] drivers: bootcount: Add ZynqMP specific bootcount support

[Vasileios Amoiridis]

On Tue, Nov 05, 2024 at 09:36:45AM +0100, Heiko Schocher wrote:
> Hello Amoiridis,
> 
> On 05.11.24 08:49, Vasileios Amoiridis wrote:
> > From: Vasileios Amoiridis <vasileios.amoiridis at 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.amoiridis at cern.ch>
> > ---
> >   MAINTAINERS                                  |  1 +
> >   arch/arm/mach-zynqmp/include/mach/hardware.h |  2 +
> >   drivers/bootcount/Kconfig                    |  6 +++
> >   drivers/bootcount/Makefile                   |  1 +
> >   drivers/bootcount/bootcount_zynqmp.c         | 47 ++++++++++++++++++++
> >   5 files changed, 57 insertions(+)
> >   create mode 100644 drivers/bootcount/bootcount_zynqmp.c
> 
> Please add a history of changes you did, see:
> 
> https://docs.u-boot.org/en/latest/develop/sending_patches.html#sending-updated-patch-versions
> 
> Hint: I prefer to use patman for this.
> 

Ah this got lost because of the rebase... In any case, a bit too
late, v1 is here [1].

[1]: https://lore.kernel.org/u-boot/20241029185814.7937-1-vassilisamir@gmail.com/

> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index 0399ed1dbf..bc27a514e8 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -860,6 +860,7 @@ M:	Michal Simek <michal.simek at amd.com>
> >   S:	Maintained
> >   T:	git https://source.denx.de/u-boot/custodians/u-boot-microblaze.git
> >   F:	arch/arm/mach-zynqmp/
> > +F:	drivers/bootcount/bootcount_zynqmp.c
> >   F:	drivers/clk/clk_zynqmp.c
> >   F:	driver/firmware/firmware-zynqmp.c
> >   F:	drivers/fpga/zynqpl.c
> > diff --git a/arch/arm/mach-zynqmp/include/mach/hardware.h b/arch/arm/mach-zynqmp/include/mach/hardware.h
> > index 49e449ebd6..3c372bd6dc 100644
> > --- a/arch/arm/mach-zynqmp/include/mach/hardware.h
> > +++ b/arch/arm/mach-zynqmp/include/mach/hardware.h
> > @@ -188,6 +188,8 @@ struct pmu_regs {
> >   	u32 gen_storage4; /* 0x40 */
> >   	u32 reserved1[1];
> >   	u32 gen_storage6; /* 0x48 */
> > +	u32 reserved2[3];
> > +	u32 pers_gen_storage2; /* 0x58 */
> >   };
> >   #define pmu_base ((struct pmu_regs *)ZYNQMP_PMU_BASEADDR)
> > diff --git a/drivers/bootcount/Kconfig b/drivers/bootcount/Kconfig
> > index fa6d8e7128..f91074d5b4 100644
> > --- a/drivers/bootcount/Kconfig
> > +++ b/drivers/bootcount/Kconfig
> > @@ -164,6 +164,12 @@ config DM_BOOTCOUNT_SYSCON
> >   	  Accessing the backend is done using the regmap interface.
> > +config DM_BOOTCOUNT_ZYNQMP
> > +	bool "Support ZynqMP PMUFW as a backing store for bootcount"
> > +	help
> > +	  Enable support for the bootcount API by utilising the Persistent
> > +	  Global General Storage Register 2 of the PMU.
> > +
> >   endmenu
> >   endif
> > diff --git a/drivers/bootcount/Makefile b/drivers/bootcount/Makefile
> > index 245f879633..0cf79e428d 100644
> > --- a/drivers/bootcount/Makefile
> > +++ b/drivers/bootcount/Makefile
> > @@ -16,3 +16,4 @@ obj-$(CONFIG_DM_BOOTCOUNT_I2C_EEPROM)	+= i2c-eeprom.o
> >   obj-$(CONFIG_DM_BOOTCOUNT_I2C)	+= bootcount_dm_i2c.o
> >   obj-$(CONFIG_DM_BOOTCOUNT_SPI_FLASH)	+= spi-flash.o
> >   obj-$(CONFIG_DM_BOOTCOUNT_SYSCON) += bootcount_syscon.o
> > +obj-$(CONFIG_DM_BOOTCOUNT_ZYNQMP)	+= bootcount_zynqmp.o
> > diff --git a/drivers/bootcount/bootcount_zynqmp.c b/drivers/bootcount/bootcount_zynqmp.c
> > new file mode 100644
> > index 0000000000..060bbdbae9
> > --- /dev/null
> > +++ b/drivers/bootcount/bootcount_zynqmp.c
> > @@ -0,0 +1,47 @@
> > +// SPDX-License-Identifier: GPL-2.0+
> > +// SPDX-FileCopyrightText: 2024 CERN (home.cern)
> > +
> > +#include <asm/arch/hardware.h>
> > +#include <bootcount.h>
> > +#include <dm.h>
> > +#include <dm/platdata.h>
> > +#include <stdio.h>
> > +#include <zynqmp_firmware.h>
> > +
> > +static int bootcount_zynqmp_set(struct udevice *dev, const u32 val)
> > +{
> > +	int ret;
> > +
> > +	ret = zynqmp_mmio_write((ulong)&pmu_base->pers_gen_storage2, 0xFF, val);
> > +	if (ret)
> > +		pr_info("%s mio write fail\n", __func__);
> 
> Nitpick: I think you do not need "mio" ...
>

Even the read/write is redundant in my opinion since the name of
the function is printed but in other cases 
(i.e drivers/clk/clk_zynqmp.c) I saw it used like this.

> > +
> > +	return ret;
> > +}
> > +
> > +static int bootcount_zynqmp_get(struct udevice *dev, u32 *val)
> > +{
> > +	int ret;
> > +
> > +	*val = 0;
> > +	ret = zynqmp_mmio_read((ulong)&pmu_base->pers_gen_storage2, val);
> > +	if (ret)
> > +		pr_info("%s mio write fail\n", __func__);
> 
> Here too... remove mio and s/write/read
>

Will fix that in v3, thanks!

> > +
> > +	return ret;
> > +}
> > +
> > +U_BOOT_DRVINFO(bootcount_zynqmp) = {
> > +	.name = "bootcount_zynqmp",
> > +};
> > +
> > +static const struct bootcount_ops bootcount_zynqmp_ops = {
> > +	.get = bootcount_zynqmp_get,
> > +	.set = bootcount_zynqmp_set,
> > +};
> > +
> > +U_BOOT_DRIVER(bootcount_zynqmp) = {
> > +	.name = "bootcount_zynqmp",
> > +	.id = UCLASS_BOOTCOUNT,
> > +	.ops = &bootcount_zynqmp_ops,
> > +};
> > 
> 
> Thanks! Beside of the nitpicks
> 
> Reviewed-by: Heiko Schocher <hs at denx.de>
> 
> bye,
> Heiko

Thank you for your time!

Cheers,
Vasilis
> -- 
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