Re: [Qemu-ppc] [Qemu-devel] ppc vga output breakage since commit c3c1bb99

[Mark Cave-Ayland]

On 01/04/15 08:55, Paolo Bonzini wrote:

> On 01/04/2015 00:34, Mark Cave-Ayland wrote:
>> On 30/03/15 12:47, Paolo Bonzini wrote:
>>
>>> On 30/03/2015 13:45, Peter Crosthwaite wrote:
>>>> Can the address_space_translate_address() length clamp be made
>>>> conditional on non-MMIO access as the RC fix? I submitted
>>>> c3c1bb99d1c11978d9ce94d1bdcf0705378c1459 as I think its the right
>>>> thing to do regardless of memory type, but in reality it only fixes a
>>>> bug I encountered with RAM memory regions. The original code ignores
>>>> address_space_translate_internal() return-by-pointer length value
>>>> absolutely and the new code uses it absolutely. Should we just if the
>>>> whole thing, old vs new behaviour on MMIO vs non-MMIO?
>>>>
>>>> Happy to submit that fixup if that's the accepted plan.
>>>
>>> I submitted what I think is the right fix (sorry Mark for misspelling
>>> your email address).  I think you're patch is correct, so I'd rather not
>>> introduce hacks for the release; we can either revert it, or fix ioport.c.
>>
>> Ah wait a second - the same patch c3c1bb99 also breaks reset on SPARC32:
>>
>> $ ./qemu-system-sparc -prom-env 'auto-boot?=false' -nographic
>> Configuration device id QEMU version 1 machine id 32
>> Probing SBus slot 0 offset 0
>> Probing SBus slot 1 offset 0
>> Probing SBus slot 2 offset 0
>> Probing SBus slot 3 offset 0
>> Probing SBus slot 4 offset 0
>> Probing SBus slot 5 offset 0
>> Invalid FCode start byte
>> CPUs: 1 x FMI,MB86904
>> UUID: 00000000-0000-0000-0000-000000000000
>> Welcome to OpenBIOS v1.1 built on Mar 12 2015 08:08
>>   Type 'help' for detailed information
>>
>> 0 > reset-all Unhandled Exception 0x00000029
>> PC = 0xffd10c08 NPC = 0xffd10c0c
>> Stopping execution
>>
>> The reset is controlled by writing a 1 to the hardware reset register at
>> physical address 0x71f00000 (system-control according to "info mtree")
>> which is handled in hw/misc/slavio_misc.c.
>>
>> Given that SYSCTRL_SIZE isn't used at all (and the access size for
>> slavio_led_mem_ops also looks wrong), the following seems to be the
>> correct fix for the reset and LED access:
>>
>>
>> --- a/hw/misc/slavio_misc.c
>> +++ b/hw/misc/slavio_misc.c
>> @@ -68,6 +68,7 @@ typedef struct APCState {
>>  } APCState;
>>
>>  #define MISC_SIZE 1
>> +#define LED_SIZE 2
>>  #define SYSCTRL_SIZE 4
>>
>>  #define AUX1_TC        0x02
>> @@ -452,13 +453,13 @@ static int slavio_misc_init1(SysBusDevice *sbd)
>>      /* 16 bit registers */
>>      /* ss600mp diag LEDs */
>>      memory_region_init_io(&s->led_iomem, OBJECT(s), &slavio_led_mem_ops, s,
>> -                          "leds", MISC_SIZE);
>> +                          "leds", LED_SIZE);
>>      sysbus_init_mmio(sbd, &s->led_iomem);
>>
>>      /* 32 bit registers */
>>      /* System control */
>>      memory_region_init_io(&s->sysctrl_iomem, OBJECT(s),
>> &slavio_sysctrl_mem_ops, s,
>> -                          "system-control", MISC_SIZE);
>> +                          "system-control", SYSCTRL_SIZE);
>>      sysbus_init_mmio(sbd, &s->sysctrl_iomem);
>>
>>      /* AUX 1 (Misc System Functions) */
>>
>>
>> Then again it is getting quite late in the release cycle...
> 
> Yes, it's better to revert for now.  Can you submit the patch above, so
> I include it in 2.4 and keep bisectability?

Sure. Is your current 2.4 branch available on github or anywhere
similar? That's just so once the patch has been applied, I have a remote
I can use to run a complete set of OpenBIOS tests.


ATB,

Mark.