Date: Tue, 3 Sep 2013 14:27:31 -0400
From: Tejun Heo <tj@kernel.org>
To: Alexander Gordeev <agordeev@redhat.com>
Cc: linux-kernel@vger.kernel.org, x86@kernel.org, linux-pci@vger.kernel.org,
        linux-ide@vger.kernel.org, Ingo Molnar <mingo@kernel.org>,
        Joerg Roedel <joro@8bytes.org>, Jan Beulich <JBeulich@suse.com>,
        Bjorn Helgaas <bhelgaas@google.com>
Subject: Re: [PATCH 3/4] AHCI: Conserve interrupts with
 pci_enable_msi_block_part() interface
Message-ID: <20130903182731.GA27092@mtj.dyndns.org>
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Hello,

On Tue, Sep 03, 2013 at 06:19:06PM +0200, Alexander Gordeev wrote:
> We must enable maximum possible number of MSIs - the one reported in
> Multiple Message Capable register. Otherwise ICH device will fallback
> to MRSM. IOW, if the result of roundup_pow_of_two(n_ports) is not what
> in Multiple Message Capable register (i.e. as roundup_pow_of_two(6) vs 16)
> ICH will enforce MRSM mode.

Hmmm... I think the interface in general is pretty messy.  Wouldn't it
be much cleaner to have a separate function to query MSICAP and let
the function just return success / failure?

Thanks.

-- 
tejun
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