[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Thu, 09 Oct 2008 21:15:52 -0700 (PDT)
From: David Miller <davem@...emloft.net>
To: akpm@...ux-foundation.org
Cc: mingo@...e.hu, netdev@...r.kernel.org
Subject: Re: drivers/net/enic/vnic_cq.c
From: Andrew Morton <akpm@...ux-foundation.org>
Date: Thu, 9 Oct 2008 21:12:17 -0700
>
> i386 allmodconfig, all trees applied:
>
> drivers/net/enic/vnic_cq.c: In function 'vnic_cq_init':
> drivers/net/enic/vnic_cq.c:65: error: implicit declaration of function 'writeq'
>
> I can't immediately find an i386 implementation of writeq.
There isn't, because only a non-atomic implementation (two writew's)
is possible.
So what ends up happening is that every driver that wants readq and
writeq does this ifdef dance:
#ifndef readq
static u64 readq(void __iomem *reg)
{
return (((u64)readl(reg + 0x4UL) << 32) |
(u64)readl(reg));
}
static void writeq(u64 val, void __iomem *reg)
{
writel(val & 0xffffffff, reg);
writel(val >> 32, reg + 0x4UL);
}
#endif
basically stating that they explicitly understand that these are
non-atomic and that the driver can handle it.
But this is completely stupid. Instead of putting this in every driver
we should put it in the 32-bit asm/io.h files and guard it with
some ifdef test, on a macro that the driver can define.
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists