Hi Michael, Have you had a chance to look at this? There's no hurry, im just curious.
Thanks, Sean > -----Original Message----- > From: Sean O. Stalley [mailto:sean.stal...@intel.com] > Sent: Monday, June 01, 2015 9:38 AM > To: Michael S. Tsirkin > Cc: qemu-devel@nongnu.org > Subject: Re: [PATCH 1/1] Add support for PCI Enhanced Allocation "BARs" > > On Sun, May 31, 2015 at 08:13:49PM +0200, Michael S. Tsirkin wrote: > > On Wed, May 13, 2015 at 10:29:42AM -0700, Sean O. Stalley wrote: > > > On Wed, May 13, 2015 at 08:09:46AM +0200, Michael S. Tsirkin wrote: > > > > On Tue, May 12, 2015 at 02:23:07PM -0700, Sean O. Stalley wrote: > > > > > On Tue, May 12, 2015 at 11:33:49AM +0200, Michael S. Tsirkin > wrote: > > > > > > On Mon, May 11, 2015 at 01:08:05PM -0700, Sean O. Stalley > wrote: > > > > > > > On Mon, May 11, 2015 at 09:26:08PM +0200, Michael S. Tsirkin > wrote: > > > > > > > > On Mon, May 11, 2015 at 11:56:44AM -0700, Sean O. Stalley > wrote: > > > > > > > > > PCI Enhanced Allocation is a new method of allocating > > > > > > > > > MMIO & IO resources for PCI devices & bridges. It can be > > > > > > > > > used instead of the traditional PCI method of using BARs. > > > > > > > > > > > > > > > > > > EA entries are hardware-initialized to a fixed address. > > > > > > > > > Unlike BARs, regions described by EA are cannot be moved. > > > > > > > > > Because of this, only devices which are perminately > > > > > > > > > connected to the PCI bus can use EA. A removeable PCI card > must not use EA. > > > > > > > > > > > > > > > > > > This patchset enables any existing QEMU PCI model to use > > > > > > > > > EA in leiu of BARs. It adds EA options to the PCI device > paramaters. > > > > > > > > > > > > > > > > > > The Enhanced Allocation ECN is publicly available here: > > > > > > > > > https://www.pcisig.com/specifications/conventional/ECN_E > > > > > > > > > nhanced_Allocation_23_Oct_2014_Final.pdf > > > > > > > > > > > > > > > > > > Signed-off-by: Sean O. Stalley <sean.stal...@intel.com> > > > > > > > > > > > > > > > > > > > > > > > > I will review this, thanks. Will you also be sending a > > > > > > > > seabios patch to support these registers? When you do, > please Cc me. > > > > > > > > > > > > > > Thanks Michael, > > > > > > > > > > > > > > I wasn't planning on sending a seabios patch. > > > > > > > > > > > > Won't this mean that bios might allocate PCI BARs conflicting > > > > > > with EA entries, causing guest to crash? > > > > > > > > > > The short answer is yes, having EA hardware without an EA-aware > bios could cause the guest to crash. > > > > > > > > > > To make matters worse, EA may cause old OSes may crash as well. > > > > > If the OS supports hot-swap, and tries to remap the BARs, it could > have the same problem. > > > > > > > > Should _CRS in ACPI be updated to exclude the EA regions? > > > > If we do this, this problem will go away, won't it? > > > > > > > > > > I think that would work, assuming the OS uses the _CRS. > > > (https://lwn.net/Articles/373551/) > > > > > > I wasn't quite sure how EA should affect ACPI. > > > This is why I pushed out the QEMU hardware changes before the EDKII > changes. > > > > > > So I'm waiting for v2 of this? > > > > I wasn't planning on changing the hardware models in this patch (at least > not until they are reviewed). > > Based on our discussion about ACPI, I was going to make changes to the > firmware patches. > I don't think I need to change anything in this patchset to fix ACPI. > > > > > > > > > > > This patch allows the user to add EA devices to an existing > > > > > machine, which is something that would never happen with real EA > hardware. > > > > > > > > > > EA devices will only be present on new platforms. > > > > > Because of this, I thought it made more sense to add EA support to > EDKII than to seabios. > > > > > Will adding EA support to seabios be necessary as well? > > > > > > > > If the problem with old OSes is fixable, then I think it's a good idea. > > > > > > > > > > > I do have some EDKII/OVMF patches I hope to send out soon. I > will Cc you on those. > > > > > > > > > > > > > > -Sean > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > --- > > > > > > > > > hw/pci/Makefile.objs | 2 +- > > > > > > > > > hw/pci/pci.c | 96 ++++++++++++++++------ > > > > > > > > > hw/pci/pci_ea.c | 203 > ++++++++++++++++++++++++++++++++++++++++++++++ > > > > > > > > > include/hw/pci/pci.h | 7 ++ > > > > > > > > > include/hw/pci/pci_ea.h | 39 +++++++++ > > > > > > > > > include/hw/pci/pci_regs.h | 4 + > > > > > > > > > include/qemu/typedefs.h | 1 + > > > > > > > > > 7 files changed, 328 insertions(+), 24 deletions(-) > > > > > > > > > create mode 100644 hw/pci/pci_ea.c create mode 100644 > > > > > > > > > include/hw/pci/pci_ea.h
