[PATCH 3/4 V4] Enable MSI support for MPC8610HPCD board

[Kumar Gala]

On May 20, 2008, at 10:29 PM, Jin Zhengxiong wrote:

>
>
>> -----Original Message-----
>> From: Kumar Gala [mailto:galak at kernel.crashing.org]
>> Sent: Tuesday, May 20, 2008 9:24 PM
>> To: Jin Zhengxiong
>> Cc: linuxppc-dev at ozlabs.org
>> Subject: Re: [PATCH 3/4 V4] Enable MSI support for MPC8610HPCD board
>>
>>> diff --git a/arch/powerpc/platforms/86xx/mpc8610_hpcd.c b/arch/
>>> powerpc/platforms/86xx/mpc8610_hpcd.c
>>> index dea1320..290d717 100644
>>> --- a/arch/powerpc/platforms/86xx/mpc8610_hpcd.c
>>> +++ b/arch/powerpc/platforms/86xx/mpc8610_hpcd.c
>>> @@ -71,9 +71,13 @@ static void __init mpc86xx_hpcd_init_irq(void)
>>> 	/* Alloc mpic structure and per isu has 16 INT entries. */
>>> 	mpic1 = mpic_alloc(np, res.start,
>>> 			MPIC_PRIMARY | MPIC_WANTS_RESET |
>> MPIC_BIG_ENDIAN,
>>> -			0, 256, " MPIC     ");
>>> +			64, 256, " MPIC     ");
>>> 	BUG_ON(mpic1 == NULL);
>>>
>>> +	mpic_assign_isu(mpic1, 0, res.start + 0x10000);
>>> +	mpic_assign_isu(mpic1, 1, res.start + 0x10800);
>>> +	mpic_assign_isu(mpic1, 2, res.start + 0x11600);
>>> +
>>
>> I don't understand why you are breaking the interrupts up like this.
>>
>> If you leave as it was, the MSIs would start at hw irq 176
>
> If the ISU size is 0, mpic will only initialize the interrupt source  
> num
> reading from
> Feature Reporting Register(FRR), For 8610 it's 104, for 8572 it is  
> 108,
> As the address
> space of the interrupt source configuration register is not
> continuous(between 0xa00-0x1600),
> with ISU=0, actually only the 16 externel interrupts and 64 internal
> interrupts were initialized.
> the Messaging interrupts and MSI interrupts were not intialized.
>
> With the original code. the Messaging interrupts would start at hwirq
> 176 and the MSIs would
> start at hwirq 224.
> By setting the ISU=64, the Messaging interrupts would start at 128 and
> the MSIs start at 176.
> And all the interrupt sources will be initialized.

Yeah, I remember this now.  What about something like:

diff --git a/arch/powerpc/sysdev/mpic.c b/arch/powerpc/sysdev/mpic.c
index 8619f2a..90de869 100644
--- a/arch/powerpc/sysdev/mpic.c
+++ b/arch/powerpc/sysdev/mpic.c
@@ -1251,6 +1251,8 @@ void __init mpic_init(struct mpic *mpic)
         if (mpic->irq_count == 0)
                 mpic->irq_count = mpic->num_sources;

+       mpic->num_sources = max(mpic->num_sources, mpic->irq_count);
+
         /* Do the HT PIC fixups on U3 broken mpic */
         DBG("MPIC flags: %x\n", mpic->flags);
         if ((mpic->flags & MPIC_U3_HT_IRQS) && (mpic->flags &  
MPIC_PRIMARY)) {


- k