Re: [PATCH -queue v0 4/6] [loongson] add basic fuloong2f support

From: Wu Zhangjin <wuzhangjin@gmail.com>
To: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org, LKML <linux-kernel@vger.kernel.org>,
	huhb@lemote.com, yanh@lemote.com, Zhang Le <r0bertz@gentoo.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Nicholas Mc Guire <der.herr@hofr.at>,
	zhangfx@lemote.com, liujl@lemote.com
Subject: Re: [PATCH -queue v0 4/6] [loongson] add basic fuloong2f support
Date: Thu, 05 Nov 2009 22:44:22 +0800	[thread overview]
Message-ID: <1257432262.3067.42.camel@falcon.domain.org> (raw)
In-Reply-To: <20091105131603.GA18232@linux-mips.org>

Hi,

On Thu, 2009-11-05 at 14:16 +0100, Ralf Baechle wrote:
> > +
> > +	if ((LOONGSON_INTISR & LOONGSON_INTEN) & LOONGSON_INT_BIT_INT0) {
> > +		imr = inb(0x21) | (inb(0xa1) << 8);
> > +		isr = inb(0x20) | (inb(0xa0) << 8);
> > +		isr &= ~0x4;	/* irq2 for cascade */
> > +		isr &= ~imr;
> > +		irq = ffs(isr) - 1;
> > +	}
> 
> Any reason why you're not using i8259_irq() from <asm/i8259.h> here?
> That function not only gets the locking right, it also minimizes the number
> of accesses to the i8259 - which even on modern silicon can be stuningly
> slow.
> 

Seems there are some differences between here and the i8259_irq(), I
forget the details, perhaps "Yan Hua" can give a detail explaination.

> > +#if 1
> > +	pci_read_config_byte(pdev, PCI_LATENCY_TIMER, &val);
> > +	printk(KERN_INFO "cs5536 acc latency 0x%x\n", val);
> > +	pci_write_config_byte(pdev, PCI_LATENCY_TIMER, 0xc0);
> > +#endif
> 
> Seems like left over debug code?
> 
> > +	return;
> > +}
> 
> And a useless return statement at the end of a void function.
> 

Okay, will remove them later.

Regards,
	Wu Zhangjin