From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45693) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ao45q-0007R8-IC for qemu-devel@nongnu.org; Thu, 07 Apr 2016 03:11:07 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ao45l-0002VW-P7 for qemu-devel@nongnu.org; Thu, 07 Apr 2016 03:11:06 -0400 Received: from mail-pa0-x243.google.com ([2607:f8b0:400e:c03::243]:34452) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ao45l-0002V5-9g for qemu-devel@nongnu.org; Thu, 07 Apr 2016 03:11:01 -0400 Received: by mail-pa0-x243.google.com with SMTP id hb4so6143352pac.1 for ; Thu, 07 Apr 2016 00:11:00 -0700 (PDT) References: <1459762426-18440-1-git-send-email-aik@ozlabs.ru> <1459762426-18440-16-git-send-email-aik@ozlabs.ru> <20160407005009.GF16485@voom.fritz.box> From: Alexey Kardashevskiy Message-ID: <570607FD.5090907@ozlabs.ru> Date: Thu, 7 Apr 2016 17:10:53 +1000 MIME-Version: 1.0 In-Reply-To: <20160407005009.GF16485@voom.fritz.box> Content-Type: text/plain; charset=koi8-r; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH qemu v15 15/17] spapr_pci: Get rid of dma_loibn List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: David Gibson Cc: Alex Williamson , qemu-ppc@nongnu.org, qemu-devel@nongnu.org, Alexander Graf On 04/07/2016 10:50 AM, David Gibson wrote: > s/dma_loibn/dma_liobn/ in subject line. > > On Mon, Apr 04, 2016 at 07:33:44PM +1000, Alexey Kardashevskiy wrote: >> We are going to have 2 DMA windows which LIOBNs are calculated from >> the PHB index and the window number using the SPAPR_PCI_LIOBN macro >> so there is no actual use for dma_liobn. >> >> This replaces dma_liobn with SPAPR_PCI_LIOBN. This marks it as unused >> in the migration stream. This renames dma_liobn to _dma_liobn as we have >> to keep the property for the CLI compatibility and we need a storage >> for it, although it has never really been used. >> >> Signed-off-by: Alexey Kardashevskiy > > This doesn't quite make sense. We can't really do that without > entirely removing support for PHBs without an 'index' value. > Basically the idea of the PHB config parameters what that you either > specified just "index" or you specified *all* the relevant addresses. > Removing option 2 might be a reasonable idea, but it shouldn't just be > done as a side effect of this other change. With this patch the > "specify everything" approach still has code, but can't work, because > such a device will never get a reasonable liobn (or worse, it might > get a duplicate liobn, because the index isn't verified in this mode). > > Then again.. the "index" approach has also bitten us with the problem > of the not-quite-big-enough MMIO space per-PHB, Any new ideas on that front? I also keep in mind that we rather want to assign interrupt numbers pool to a PHB based on its index rather than allocate them from the global machine interrupt number space so this is one more vote for keeping the index. > so I'm not entirely > sure that making it the only choice is the right way to go either. I can imagine the user wanting to change MMIO addresses (so they should remain properties) but changing LIOBN from the command line does not seem useful at all. > The short term approach to handle DDW might be to instead add a > dma64_liobn property. So everywhere where I want to have a loop through all TCE tables and use SPAPR_PCI_LIOBN(index, i), I cannot really do that if I have 2 separate properties. Not extremely convenient. > >> --- >> Changes: >> v15: >> * new to the series >> --- >> hw/ppc/spapr_pci.c | 17 ++++++----------- >> include/hw/pci-host/spapr.h | 2 +- >> 2 files changed, 7 insertions(+), 12 deletions(-) >> >> diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c >> index f864fde..d4bdb27 100644 >> --- a/hw/ppc/spapr_pci.c >> +++ b/hw/ppc/spapr_pci.c >> @@ -1306,7 +1306,7 @@ static void spapr_phb_realize(DeviceState *dev, Error **errp) >> if (sphb->index != (uint32_t)-1) { >> hwaddr windows_base; >> >> - if ((sphb->buid != (uint64_t)-1) || (sphb->dma_liobn != (uint32_t)-1) >> + if ((sphb->buid != (uint64_t)-1) >> || (sphb->mem_win_addr != (hwaddr)-1) >> || (sphb->io_win_addr != (hwaddr)-1)) { >> error_setg(errp, "Either \"index\" or other parameters must" >> @@ -1321,7 +1321,6 @@ static void spapr_phb_realize(DeviceState *dev, Error **errp) >> } >> >> sphb->buid = SPAPR_PCI_BASE_BUID + sphb->index; >> - sphb->dma_liobn = SPAPR_PCI_LIOBN(sphb->index, 0); >> >> windows_base = SPAPR_PCI_WINDOW_BASE >> + sphb->index * SPAPR_PCI_WINDOW_SPACING; >> @@ -1334,11 +1333,6 @@ static void spapr_phb_realize(DeviceState *dev, Error **errp) >> return; >> } >> >> - if (sphb->dma_liobn == (uint32_t)-1) { >> - error_setg(errp, "LIOBN not specified for PHB"); >> - return; >> - } >> - >> if (sphb->mem_win_addr == (hwaddr)-1) { >> error_setg(errp, "Memory window address not specified for PHB"); >> return; >> @@ -1453,7 +1447,7 @@ static void spapr_phb_realize(DeviceState *dev, Error **errp) >> } >> } >> >> - tcet = spapr_tce_new_table(DEVICE(sphb), sphb->dma_liobn); >> + tcet = spapr_tce_new_table(DEVICE(sphb), SPAPR_PCI_LIOBN(sphb->index, 0)); >> if (!tcet) { >> error_setg(errp, "Unable to create TCE table for %s", >> sphb->dtbusname); >> @@ -1479,7 +1473,8 @@ static int spapr_phb_children_reset(Object *child, void *opaque) >> >> void spapr_phb_dma_reset(sPAPRPHBState *sphb) >> { >> - sPAPRTCETable *tcet = spapr_tce_find_by_liobn(sphb->dma_liobn); >> + uint32_t liobn = SPAPR_PCI_LIOBN(sphb->index, 0); >> + sPAPRTCETable *tcet = spapr_tce_find_by_liobn(liobn); >> >> if (tcet && tcet->enabled) { >> spapr_tce_table_disable(tcet); >> @@ -1507,7 +1502,7 @@ static void spapr_phb_reset(DeviceState *qdev) >> static Property spapr_phb_properties[] = { >> DEFINE_PROP_UINT32("index", sPAPRPHBState, index, -1), >> DEFINE_PROP_UINT64("buid", sPAPRPHBState, buid, -1), >> - DEFINE_PROP_UINT32("liobn", sPAPRPHBState, dma_liobn, -1), >> + DEFINE_PROP_UINT32("liobn", sPAPRPHBState, _dma_liobn, -1), >> DEFINE_PROP_UINT64("mem_win_addr", sPAPRPHBState, mem_win_addr, -1), >> DEFINE_PROP_UINT64("mem_win_size", sPAPRPHBState, mem_win_size, >> SPAPR_PCI_MMIO_WIN_SIZE), >> @@ -1595,7 +1590,7 @@ static const VMStateDescription vmstate_spapr_pci = { >> .post_load = spapr_pci_post_load, >> .fields = (VMStateField[]) { >> VMSTATE_UINT64_EQUAL(buid, sPAPRPHBState), >> - VMSTATE_UINT32_EQUAL(dma_liobn, sPAPRPHBState), >> + VMSTATE_UNUSED(4), /* former dma_liobn */ >> VMSTATE_UINT64_EQUAL(mem_win_addr, sPAPRPHBState), >> VMSTATE_UINT64_EQUAL(mem_win_size, sPAPRPHBState), >> VMSTATE_UINT64_EQUAL(io_win_addr, sPAPRPHBState), >> diff --git a/include/hw/pci-host/spapr.h b/include/hw/pci-host/spapr.h >> index 7848366..3fca1c3 100644 >> --- a/include/hw/pci-host/spapr.h >> +++ b/include/hw/pci-host/spapr.h >> @@ -56,7 +56,7 @@ struct sPAPRPHBState { >> hwaddr mem_win_addr, mem_win_size, io_win_addr, io_win_size; >> MemoryRegion memwindow, iowindow, msiwindow; >> >> - uint32_t dma_liobn; >> + uint32_t _dma_liobn; >> hwaddr dma_win_addr, dma_win_size; >> AddressSpace iommu_as; >> MemoryRegion iommu_root; > -- Alexey