6c3829a265
The pseries guests do not normally allocate PCI resources and rely on the system firmware doing so. Furthermore at least at some point in the past the pseries guests won't even allowed to change BARs, probably it is still the case for phyp. So since the initial commit we have [1] which prevents resource reallocation. This is not a problem until we want specific BAR alignments, for example, PAGE_SIZE==64k to make sure we can still map MMIO BARs directly. For the boot time devices we handle this in SLOF [2] but since QEMU's RTAS does not allocate BARs, the guest does this instead and does not align BARs even if Linux is given pci=resource_alignment=16@pci:0:0 as PCI_PROBE_ONLY makes Linux ignore alignment requests. ARM folks added a dial to control PCI_PROBE_ONLY via the device tree [3]. This makes use of the dial to advertise to the guest that we can handle BAR reassignments. This limits the change to the latest pseries machine to avoid old guests explosion. We do not remove the flag from [1] as pseries guests are still supported under phyp so having that removed may cause problems. [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/powerpc/platforms/pseries/setup.c?h=v5.1#n773 [2] https://git.qemu.org/?p=SLOF.git;a=blob;f=board-qemu/slof/pci-phb.fs;h=06729bcf77a0d4e900c527adcd9befe2a269f65d;hb=HEAD#l338 [3] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=f81c11af Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Message-Id: <20190719043734.108462-1-aik@ozlabs.ru> Reviewed-by: Greg Kurz <groug@kaod.org> Signed-off-by: David Gibson <david@gibson.dropbear.id.au> |
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| .. | ||
| fdt.h | ||
| mac_dbdma.h | ||
| openpic_kvm.h | ||
| openpic.h | ||
| pnv_core.h | ||
| pnv_lpc.h | ||
| pnv_occ.h | ||
| pnv_psi.h | ||
| pnv_xive.h | ||
| pnv_xscom.h | ||
| pnv.h | ||
| ppc4xx.h | ||
| ppc_e500.h | ||
| ppc.h | ||
| spapr_cpu_core.h | ||
| spapr_drc.h | ||
| spapr_irq.h | ||
| spapr_ovec.h | ||
| spapr_rtas.h | ||
| spapr_tpm_proxy.h | ||
| spapr_vio.h | ||
| spapr_xive.h | ||
| spapr.h | ||
| xics_spapr.h | ||
| xics.h | ||
| xive_regs.h | ||
| xive.h | ||