Thought I would request help from AHCI experts to solve an issue I encounter. Apologies in advance if this is not the right forum for requesting such help. Background - I am writing a minimal AHCI driver that would be invoked within Xen environment upon a system crash. It is minimal in the sense it doesn't do much in the way of initializing the device, setting up interrupts etc. as dom0 would take care of initialization and we will be using it in polled mode with no interrupts, so no need to setup interrupts. Upon a system crash, I am able to get to abar and HBA registers etc. I am also able to map the relevant memory regions appropriately within Xen and access it. But, when I issue a command by setting the relevant free slot specific bit in the port command issue register (pxci), the bit I set for the slot in pxci is not getting reset as it should upon successful execution of the command. As an experiment, I simply tried to stop/start the HBA engine by setting the ST bit in the command register (PxCMD) to 0 but the CR, FR bits etc. in PxCMD is not getting reset by the HBA upon ST reset as expected. It appears the HBA engine is not responding as it should. If you can share any thought as to why the HBA is not responding though the PCI space, abar, port registers etc. looks fine that would be much appreciated. Thanks! Kamala -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
