Re: [PATCH v6 09/42] powerpc/powernv: DMA32 cleanup

Gavin Shan
2015-08-11T00:19:45Z

On Mon, Aug 10, 2015 at 06:07:27PM +1000, Alexey Kardashevskiy wrote:
>On 08/06/2015 02:11 PM, Gavin Shan wrote:
>>The patch cleans up DMA32 in pci-ioda.c. It shouldn't introduce
>>behavioural changes:
>>
>> * Rename various fields in "struct pnv_phb" and "struct pnv_ioda_pe"
>> as 32-bits DMA should be related to "DMA", not "TCE".
>
>s/dma_weight/dma32_weight/ is ok (does not add much though_ but the rest is
>not. The "tce32_" fields are still TCEs (translation entries) while DMA is a
>process initiated by a device which does not know about how exactly DMA
>addresses are translated later. Since we are on the host side and we actually
>manage TCE tables here, I suggest keeping the "tce32_" prefix for TCE tables
>and memory they use.
>

Ok. Will change accordingly.

>> * Removed struct pnv_ioda_pe::tce32_segcount.
>
>That's confusing - I had to walk through patches to find out where you
>stopped using it. It would be simpler if you put this particular change to
>
>[PATCH v6 02/42] powerpc/powernv: Drop pnv_ioda_setup_dev_PE()
>
>where you remove dead code.
>

I'll try to reorder the patch...

>
>>
>>Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
>>---
>> arch/powerpc/platforms/powernv/pci-ioda.c | 48 +++++++++++++++----------------
>> arch/powerpc/platforms/powernv/pci.h | 7 ++---
>> 2 files changed, 27 insertions(+), 28 deletions(-)
>>
>>diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
>>index 7342cfd..8456f37 100644
>>--- a/arch/powerpc/platforms/powernv/pci-ioda.c
>>+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
>>@@ -917,7 +917,7 @@ static void pnv_ioda_link_pe_by_weight(struct pnv_phb *phb,
>> struct pnv_ioda_pe *lpe;
>>
>> list_for_each_entry(lpe, &phb->ioda.pe_dma_list, dma_link) {
>>- if (lpe->dma_weight < pe->dma_weight) {
>>+ if (lpe->dma32_weight < pe->dma32_weight) {
>> list_add_tail(&pe->dma_link, &lpe->dma_link);
>> return;
>> }
>>@@ -942,14 +942,14 @@ static unsigned int pnv_ioda_dma_weight(struct pci_dev *dev)
>> if (dev->class == PCI_CLASS_SERIAL_USB_UHCI ||
>> dev->class == PCI_CLASS_SERIAL_USB_OHCI ||
>> dev->class == PCI_CLASS_SERIAL_USB_EHCI)
>>- return 3 * phb->ioda.tce32_count;
>>+ return 3 * phb->ioda.dma32_segcount;
>>
>> /* Increase the weight of RAID (includes Obsidian) */
>> if ((dev->class >> 8) == PCI_CLASS_STORAGE_RAID)
>>- return 15 * phb->ioda.tce32_count;
>>+ return 15 * phb->ioda.dma32_segcount;
>>
>> /* Default */
>>- return 10 * phb->ioda.tce32_count;
>>+ return 10 * phb->ioda.dma32_segcount;
>> }
>>
>> static int __pnv_ioda_phb_dma_weight(struct pci_dev *pdev, void *data)
>>@@ -1057,7 +1057,7 @@ static void pnv_ioda_setup_same_PE(struct pci_bus *bus, struct pnv_ioda_pe *pe)
>> continue;
>> }
>> pdn->pe_number = pe->pe_number;
>>- pe->dma_weight += pnv_ioda_dma_weight(dev);
>>+ pe->dma32_weight += pnv_ioda_dma_weight(dev);
>> if ((pe->flags & PNV_IODA_PE_BUS_ALL) && dev->subordinate)
>> pnv_ioda_setup_same_PE(dev->subordinate, pe);
>> }
>>@@ -1094,10 +1094,10 @@ static void pnv_ioda_setup_bus_PE(struct pci_bus *bus, bool all)
>> pe->flags |= (all ? PNV_IODA_PE_BUS_ALL : PNV_IODA_PE_BUS);
>> pe->pbus = bus;
>> pe->pdev = NULL;
>>- pe->tce32_seg = -1;
>>+ pe->dma32_seg = -1;
>> pe->mve_number = -1;
>> pe->rid = bus->busn_res.start << 8;
>>- pe->dma_weight = 0;
>>+ pe->dma32_weight = 0;
>>
>> if (all)
>> pe_info(pe, "Secondary bus %d..%d associated with PE#%d\n",
>>@@ -1460,7 +1460,7 @@ static void pnv_ioda_setup_vf_PE(struct pci_dev *pdev, u16 num_vfs)
>> pe->flags = PNV_IODA_PE_VF;
>> pe->pbus = NULL;
>> pe->parent_dev = pdev;
>>- pe->tce32_seg = -1;
>>+ pe->dma32_seg = -1;
>> pe->mve_number = -1;
>> pe->rid = (pci_iov_virtfn_bus(pdev, vf_index) << 8) |
>> pci_iov_virtfn_devfn(pdev, vf_index);
>>@@ -1936,7 +1936,7 @@ static void pnv_pci_ioda_setup_dma_pe(struct pnv_phb *phb,
>> /* XXX FIXME: Allocate multi-level tables on PHB3 */
>>
>> /* We shouldn't already have a 32-bit DMA associated */
>>- if (WARN_ON(pe->tce32_seg >= 0))
>>+ if (WARN_ON(pe->dma32_seg >= 0))
>> return;
>>
>> tbl = pnv_pci_table_alloc(phb->hose->node);
>>@@ -1945,7 +1945,7 @@ static void pnv_pci_ioda_setup_dma_pe(struct pnv_phb *phb,
>> pnv_pci_link_table_and_group(phb->hose->node, 0, tbl, &pe->table_group);
>>
>> /* Grab a 32-bit TCE table */
>>- pe->tce32_seg = base;
>>+ pe->dma32_seg = base;
>> pe_info(pe, " Setting up 32-bit TCE table at %08x..%08x\n",
>> (base << 28), ((base + segs) << 28) - 1);
>>
>>@@ -2006,8 +2006,8 @@ static void pnv_pci_ioda_setup_dma_pe(struct pnv_phb *phb,
>> return;
>> fail:
>> /* XXX Failure: Try to fallback to 64-bit only ? */
>>- if (pe->tce32_seg >= 0)
>>- pe->tce32_seg = -1;
>>+ if (pe->dma32_seg >= 0)
>>+ pe->dma32_seg = -1;
>> if (tce_mem)
>> __free_pages(tce_mem, get_order(TCE32_TABLE_SIZE * segs));
>> if (tbl) {
>>@@ -2405,7 +2405,7 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
>> int64_t rc;
>>
>> /* We shouldn't already have a 32-bit DMA associated */
>>- if (WARN_ON(pe->tce32_seg >= 0))
>>+ if (WARN_ON(pe->dma32_seg >= 0))
>> return;
>>
>> /* TVE #1 is selected by PCI address bit 59 */
>>@@ -2415,7 +2415,7 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
>> pe->pe_number);
>>
>> /* The PE will reserve all possible 32-bits space */
>>- pe->tce32_seg = 0;
>>+ pe->dma32_seg = 0;
>> pe_info(pe, "Setting up 32-bit TCE table at 0..%08x\n",
>> phb->ioda.m32_pci_base);
>>
>>@@ -2432,8 +2432,8 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
>>
>> rc = pnv_pci_ioda2_setup_default_config(pe);
>> if (rc) {
>>- if (pe->tce32_seg >= 0)
>>- pe->tce32_seg = -1;
>>+ if (pe->dma32_seg >= 0)
>>+ pe->dma32_seg = -1;
>> return;
>> }
>>
>>@@ -2452,7 +2452,7 @@ static void pnv_ioda_setup_dma(struct pnv_phb *phb)
>> /* Calculate the PHB's DMA weight */
>> dma_weight = pnv_ioda_phb_dma_weight(phb);
>> pr_info("PCI%04x has %ld DMA32 segments, total weight %d\n",
>>- hose->global_number, phb->ioda.tce32_count, dma_weight);
>>+ hose->global_number, phb->ioda.dma32_segcount, dma_weight);
>>
>> pnv_pci_ioda_setup_opal_tce_kill(phb);
>>
>>@@ -2461,7 +2461,7 @@ static void pnv_ioda_setup_dma(struct pnv_phb *phb)
>> * weight
>> */
>> list_for_each_entry(pe, &phb->ioda.pe_dma_list, dma_link) {
>>- if (!pe->dma_weight)
>>+ if (!pe->dma32_weight)
>> continue;
>>
>> /*
>>@@ -2472,15 +2472,15 @@ static void pnv_ioda_setup_dma(struct pnv_phb *phb)
>> if (phb->type == PNV_PHB_IODA1) {
>> unsigned int segs, base = 0;
>>
>>- if (pe->dma_weight <
>>- dma_weight / phb->ioda.tce32_count)
>>+ if (pe->dma32_weight <
>>+ dma_weight / phb->ioda.dma32_segcount)
>> segs = 1;
>> else
>>- segs = (pe->dma_weight *
>>- phb->ioda.tce32_count) / dma_weight;
>>+ segs = (pe->dma32_weight *
>>+ phb->ioda.dma32_segcount) / dma_weight;
>>
>> pe_info(pe, "DMA32 weight %d, assigned %d segments\n",
>>- pe->dma_weight, segs);
>>+ pe->dma32_weight, segs);
>> pnv_pci_ioda_setup_dma_pe(phb, pe, base, segs);
>>
>> base += segs;
>>@@ -3211,7 +3211,7 @@ static void __init pnv_pci_init_ioda_phb(struct device_node *np,
>> mutex_init(&phb->ioda.pe_list_mutex);
>>
>> /* Calculate how many 32-bit TCE segments we have */
>>- phb->ioda.tce32_count = phb->ioda.m32_pci_base >> 28;
>>+ phb->ioda.dma32_segcount = phb->ioda.m32_pci_base >> 28;
>>
>> #if 0 /* We should really do that ... */
>> rc = opal_pci_set_phb_mem_window(opal->phb_id,
>>diff --git a/arch/powerpc/platforms/powernv/pci.h b/arch/powerpc/platforms/powernv/pci.h
>>index addd3f7..574fe43 100644
>>--- a/arch/powerpc/platforms/powernv/pci.h
>>+++ b/arch/powerpc/platforms/powernv/pci.h
>>@@ -61,11 +61,10 @@ struct pnv_ioda_pe {
>> /* "Weight" assigned to the PE for the sake of DMA resource
>> * allocations
>> */
>>- unsigned int dma_weight;
>>+ unsigned int dma32_weight;
>>
>> /* "Base" iommu table, ie, 4K TCEs, 32-bit DMA */
>>- int tce32_seg;
>>- int tce32_segcount;
>>+ int dma32_seg;
>> struct iommu_table_group table_group;
>>
>> /* 64-bit TCE bypass region */
>>@@ -181,7 +180,7 @@ struct pnv_phb {
>> unsigned char pe_rmap[0x10000];
>>
>> /* 32-bit TCE tables allocation */
>>- unsigned long tce32_count;
>>+ unsigned long dma32_segcount;
>>
>> /* Sorted list of used PE's, sorted at
>> * boot for resource allocation purposes
>>

Thanks,
Gavin