[PATCH 2/5] powerpc/fsl_msi: add MSIIR1 support for MPIC v4.3

[Scott Wood]

On 06/16/2013 10:00:01 PM, Lian Minghuan-b31939 wrote:
> Hi Scott,
> 
> please see my comments inline.
> 
> On 06/15/2013 06:09 AM, Scott Wood wrote:
>> On 06/14/2013 02:15:56 AM, Minghuan Lian wrote:
>>> diff --git a/arch/powerpc/sysdev/fsl_msi.h  
>>> b/arch/powerpc/sysdev/fsl_msi.h
>>> index 8225f86..43a9d99 100644
>>> --- a/arch/powerpc/sysdev/fsl_msi.h
>>> +++ b/arch/powerpc/sysdev/fsl_msi.h
>>> @@ -16,7 +16,7 @@
>>>  #include <linux/of.h>
>>>  #include <asm/msi_bitmap.h>
>>> 
>>> -#define NR_MSI_REG        8
>>> +#define NR_MSI_REG        16
>>>  #define IRQS_PER_MSI_REG    32
>>>  #define NR_MSI_IRQS    (NR_MSI_REG * IRQS_PER_MSI_REG)
>> 
>> I don't see where you update all_avail in fsl_of_msi_probe.
>> 
>> We should also be bounds-checking the contents of  
>> msi-available-ranges.
>> Currently it looks like we just silently overrun the bitmap if we  
>> get bad
>> input from the device tree.
>> 
> [Minghuan] all_avail definition: static const u32 all_avail[] = { 0,  
> NR_MSI_IRQS };
> When changing NR_MSI_REG to 16, NR_MSI_IRQS has been changed to  
> 16*32, and all_avail also is updated.

That's my point.  It shouldn't change for older hardware.

> Before calling fsl_msi_setup_hwirq(), the code has checked  
> 'msi-available-ranges',  only the interrupts lied in  
> 'msi-available-ranges' will be initialized by call  
> fsl_msi_setup_hwirq() , and the corresponding bitmap will be freed. I  
> moved msi_bitmap_free_hwirqs() to fsl_msi_setup_hwirq(), because the  
> code would generate different bitmap when using MSIIR or MSIIR1.

And what happens if msi-available-ranges is bad, and refers to  
non-existent MSIs past the end of the bitmap?

-Scott