Bug 205201 - Booting halts if Dawicontrol DC-2976 UW SCSI board installed, unless RAM size limited to 3500M

[Christian Zigotzky]

On 21 November 2019 at 01:16 pm, Christian Zigotzky wrote:
> On 21 November 2019 at 08:29 am, Christoph Hellwig wrote:
>> On Sat, Nov 16, 2019 at 08:06:05AM +0100, Christian Zigotzky wrote:
>>> /*
>>>   *  DMA addressing mode.
>>>   *
>>>   *  0 : 32 bit addressing for all chips.
>>>   *  1 : 40 bit addressing when supported by chip.
>>>   *  2 : 64 bit addressing when supported by chip,
>>>   *      limited to 16 segments of 4 GB -> 64 GB max.
>>>   */
>>> #define   SYM_CONF_DMA_ADDRESSING_MODE 
>>> CONFIG_SCSI_SYM53C8XX_DMA_ADDRESSING_MODE
>>>
>>> Cyrus config:
>>>
>>> CONFIG_SCSI_SYM53C8XX_DMA_ADDRESSING_MODE=1
>>>
>>> I will configure “0 : 32 bit addressing for all chips” for the RC8. 
>>> Maybe this is the solution.
>> 0 means you are going to do bounce buffering a lot, which seems
>> generally like a bad idea.
>>
>> But why are we talking about the sym53c8xx driver now?  The last issue
>> you reported was about video4linux allocations.
>>
> Both drivers have the same problem. They don't work if we have more 
> than 3.5GB RAM. I try to find a solution until you have a good 
> solution. I have already a solution for V4L but I still need one for 
> the sym53c8xx driver.
OK, you mean that "0" is a bad idea but maybe it works until you have a 
solution. ;-)