Gerd Hoffmann wrote:
] Hi, ] ]> Attached is a two part version of the previous patch. Stage1 is enough ]> to get through most OS installs. Stage2 adds unaligned buffer support ]> needed for MS-DOS. ] ]Hmm, patch #1 is still a collection of multiple changes, looks a bit ]like trying this and that until it somehow worked, without figuring ]which changes where needed to make the box boot.
Thank you for the feedback. This is a pretty harsh assessment of work that transforms non-functioning code into something usable on real hardware. Have you ever written code for real hardware or do work strictly with software models?
] Also the changelog ]should describe what was changed and why, not only the effect of the ]change.
These documents will help you understand the changes: http://download.intel.com/technology/serialata/pdf/rev1_3.pdf http://www.lttconn.com/res/lttconn/pdres/201005/20100521170123066.pdf
]Polling the IRQ status looks like a sensible thing to do. Note that ]there might be multiple bits set in the IRQ status register, so you ]can't use irqbits == 0x01 to check the status. qemu fails to boot ]because of that bug.
Have you considered the possibility that the reason this works on real hardware and not qemu is that the qemu AHCI model has an erratum?
] Also it isn't obvious why you are looking for ]others than the "Device to Host Register FIS" interrupt. Care to explain?
I don't understand this question.
]I've attached a patch which switches ahci over to irq status polling, ]based on your patch. Works nicely in qemu. Can you give it a spin on ]real hardware?
It fails on real (AMD) hardware.
I am surprised by qemu bias of your questions. The type of question I expected is "great to hear it works on AMD hardware, but what about Intel hardware?" My answer would be that I cannot easily test the code on Intel hardware.
Thanks, Scott