Re: [dpdk-dev] [PATCH] config: disable iova phys for dpaa and 1588 for dpaa2

[Nipun Gupta <nipun.gupta@nxp.com>]

Hi David,

> -----Original Message-----
> From: David Marchand <david.marchand@redhat.com>
> Sent: Sunday, October 27, 2019 4:33 PM
> To: Nipun Gupta <nipun.gupta@nxp.com>
> Cc: dev <dev@dpdk.org>; Yigit, Ferruh <ferruh.yigit@intel.com>; Hemant
> Agrawal <hemant.agrawal@nxp.com>; Sachin Saxena
> <sachin.saxena@nxp.com>; Thomas Monjalon <thomas@monjalon.net>
> Subject: Re: [dpdk-dev] [PATCH] config: disable iova phys for dpaa and 1588
> for dpaa2
> 
> On Fri, Oct 4, 2019 at 1:26 PM Nipun Gupta <nipun.gupta@nxp.com> wrote:
> >
> > IOVA_PHYS flag is not required in the DPAA config, thus disable it.
> > Also, disable the 1588 timer support by default on DPAA2 platform
> > due to the performance impact
> 
> With this patch, we don't have a single target using the 1588 timer support.
> This means that it will get broken in the future.
> 
> Is this used?

Yes, this is enabled when PTP client application is used. We have by default disabled it 
because it has performance implications. We enable it in our system testing from time to 
time basis.

> 
> >
> > Signed-off-by: Nipun Gupta <nipun.gupta@nxp.com>
> 
> With this patch, the meson configuration is unaligned with the make
> configuration.

I am not sure if I get this. In meson build as you mentioned:
- config/meson.build:dpdk_conf.set('RTE_LIBRTE_DPAA2_USE_PHYS_IOVA', true)
- config/arm/meson.build: ['RTE_LIBRTE_DPAA2_USE_PHYS_IOVA', false]]

And in Makefile:
config/common_base: CONFIG_RTE_LIBRTE_DPAA2_USE_PHYS_IOVA=y
config/defconfig_arm64-dpaa2-linuxapp-gcc:CONFIG_RTE_LIBRTE_DPAA2_USE_PHYS_IOVA=n

And now we have:
config/defconfig_arm64-dpaa-linuxapp-gcc:CONFIG_RTE_LIBRTE_DPAA2_USE_PHYS_IOVA=n

Can you please let me know if I need to make any change for meson build.

> 
> If I look before the patch:
> 
> origin/master:config/meson.build:dpdk_conf.set('RTE_LIBRTE_DPAA2_USE_
> PHYS_IOVA',
> true)
> origin/master:config/arm/meson.build:
> ['RTE_LIBRTE_DPAA2_USE_PHYS_IOVA', false]]
> 
> origin/master:config/common_base:CONFIG_RTE_LIBRTE_DPAA2_USE_PHY
> S_IOVA=y
> origin/master:config/defconfig_arm64-dpaa2-linuxapp-
> gcc:CONFIG_RTE_LIBRTE_DPAA2_USE_PHYS_IOVA=n
> 
> And in the history, I understand:
> - option (with dpaa2 in the name) introduced and enabled for all
> - later, disabled for dpaa2
> 
> Does it mean the option can be removed?

Here again, we use this option when running DPDK in Virtual Machine (Direct Assignment). 
By default this option is disabled, but for VM scenarios we use this option extensively.

Thanks,
Nipun

> 
> 
> --
> David Marchand