Messages in this thread | | | From | Thomas Gleixner <> | Subject | Re: [patch V2 43/46] genirq/msi: Provide and use msi_domain_set_default_info_flags() | Date | Fri, 28 Aug 2020 20:42:21 +0200 |
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On Thu, Aug 27 2020 at 09:17, Marc Zyngier wrote: > On 2020-08-26 12:17, Thomas Gleixner wrote: >> #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN >> +void msi_domain_set_default_info_flags(struct msi_domain_info *info) >> +{ >> + /* Required so that a device latches a valid MSI message on startup >> */ >> + info->flags |= MSI_FLAG_ACTIVATE_EARLY; > > As far as I remember the story behind this flag (it's been a while), > it was working around a PCI-specific issue, hence being located in > the PCI code.
Yes. Some cards misbehave when there is no valid message programmed and MSI is enabled.
> Now, the "program the MSI before enabling it" concept makes sense no > matter what bus this is on, and I wonder why we are even keeping this > flag around.
> Can't we just drop it together with the check in > msi_domain_alloc_irqs()?
I'm fine with that.
Thanks,
tglx
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