[PATCH v9 16/26] powerpc/powernv/ioda1: Improve DMA32 segment track
Gavin Shan
gwshan at linux.vnet.ibm.com
Thu May 5 11:55:28 AEST 2016
On Wed, May 04, 2016 at 11:20:01PM +1000, Gavin Shan wrote:
>On Tue, May 03, 2016 at 03:41:35PM +1000, Gavin Shan wrote:
>>In current implementation, the DMA32 segments required by one specific
>>PE isn't calculated with the information hold in the PE independently.
>>It conflicts with the PCI hotplug design: PE centralized, meaning the
>>PE's DMA32 segments should be calculated from the information hold in
>>the PE independently.
>>
>>This introduces an array (@dma32_segmap) for every PHB to track the
>>DMA32 segmeng usage. Besides, this moves the logic calculating PE's
>>consumed DMA32 segments to pnv_pci_ioda1_setup_dma_pe() so that PE's
>>DMA32 segments are calculated/allocated from the information hold in
>>the PE (DMA32 weight). Also the logic is improved: we try to allocate
>>as much DMA32 segments as we can. It's acceptable that number of DMA32
>>segments less than the expected number are allocated.
>>
>>Signed-off-by: Gavin Shan <gwshan at linux.vnet.ibm.com>
>
>This can cause overlapped DMA32 segments to different PEs in some cases.
>I already had the fix and hold for posting after discussion with Michael
>on how to handle the series tomorrow.
>
I'm going to send v10 as a reply to this thread.
Thanks,
Gavin
>>---
>> arch/powerpc/platforms/powernv/pci-ioda.c | 110 ++++++++++++++++--------------
>> arch/powerpc/platforms/powernv/pci.h | 7 +-
>> 2 files changed, 61 insertions(+), 56 deletions(-)
>>
>>diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
>>index f70a4e0..cfd2906 100644
>>--- a/arch/powerpc/platforms/powernv/pci-ioda.c
>>+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
>>@@ -2011,27 +2011,57 @@ static unsigned int pnv_pci_ioda_pe_dma_weight(struct pnv_ioda_pe *pe)
>> }
>>
>> static void pnv_pci_ioda1_setup_dma_pe(struct pnv_phb *phb,
>>- struct pnv_ioda_pe *pe,
>>- unsigned int base,
>>- unsigned int segs)
>>+ struct pnv_ioda_pe *pe)
>> {
>>
>> struct page *tce_mem = NULL;
>> struct iommu_table *tbl;
>>- unsigned int tce32_segsz, i;
>>+ unsigned int weight, total_weight = 0;
>>+ unsigned int tce32_segsz, base, segs, i;
>> int64_t rc;
>> void *addr;
>>
>> /* XXX FIXME: Handle 64-bit only DMA devices */
>> /* XXX FIXME: Provide 64-bit DMA facilities & non-4K TCE tables etc.. */
>> /* XXX FIXME: Allocate multi-level tables on PHB3 */
>>+ pci_walk_bus(phb->hose->bus, pnv_pci_ioda_dev_dma_weight,
>>+ &total_weight);
>>+ weight = pnv_pci_ioda_pe_dma_weight(pe);
>>+
>>+ segs = (weight * phb->ioda.dma32_count) / total_weight;
>>+ if (!segs)
>>+ segs = 1;
>>+
>>+ /*
>>+ * Allocate contiguous DMA32 segments. We begin with the expected
>>+ * number of segments. With one more attempt, the number of DMA32
>>+ * segments to be allocated is decreased by one until one segment
>>+ * is allocated successfully.
>>+ */
>>+ do {
>>+ for (base = 0; base <= phb->ioda.dma32_count - segs; base++) {
>>+ for (i = base; i < base + segs; i++) {
>>+ if (phb->ioda.dma32_segmap[i] !=
>>+ IODA_INVALID_PE)
>>+ goto found;
>>+ }
>>+ }
>>+ } while (segs--);
>>+
>>+ if (!segs) {
>>+ pe_warn(pe, "No available DMA32 segments\n");
>>+ return;
>>+ }
>>
>>+found:
>> tbl = pnv_pci_table_alloc(phb->hose->node);
>> iommu_register_group(&pe->table_group, phb->hose->global_number,
>> pe->pe_number);
>> pnv_pci_link_table_and_group(phb->hose->node, 0, tbl, &pe->table_group);
>>
>> /* Grab a 32-bit TCE table */
>>+ pe_info(pe, "DMA weight %d (%d), assigned (%d) %d DMA32 segments\n",
>>+ weight, total_weight, base, segs);
>> pe_info(pe, " Setting up 32-bit TCE table at %08x..%08x\n",
>> base * PNV_IODA1_DMA32_SEGSIZE,
>> (base + segs) * PNV_IODA1_DMA32_SEGSIZE - 1);
>>@@ -2068,6 +2098,10 @@ static void pnv_pci_ioda1_setup_dma_pe(struct pnv_phb *phb,
>> }
>> }
>>
>>+ /* Setup DMA32 segment mapping */
>>+ for (i = base; i < base + segs; i++)
>>+ phb->ioda.dma32_segmap[i] = pe->pe_number;
>>+
>> /* Setup linux iommu table */
>> pnv_pci_setup_iommu_table(tbl, addr, tce32_segsz * segs,
>> base * PNV_IODA1_DMA32_SEGSIZE,
>>@@ -2542,73 +2576,34 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
>> static void pnv_ioda_setup_dma(struct pnv_phb *phb)
>> {
>> struct pci_controller *hose = phb->hose;
>>- unsigned int weight, total_weight, dma_pe_count;
>>- unsigned int residual, remaining, segs, base;
>> struct pnv_ioda_pe *pe;
>>-
>>- total_weight = 0;
>>- pci_walk_bus(phb->hose->bus, pnv_pci_ioda_dev_dma_weight,
>>- &total_weight);
>>-
>>- dma_pe_count = 0;
>>- list_for_each_entry(pe, &phb->ioda.pe_list, list) {
>>- weight = pnv_pci_ioda_pe_dma_weight(pe);
>>- if (weight > 0)
>>- dma_pe_count++;
>>- }
>>+ unsigned int weight;
>>
>> /* If we have more PE# than segments available, hand out one
>> * per PE until we run out and let the rest fail. If not,
>> * then we assign at least one segment per PE, plus more based
>> * on the amount of devices under that PE
>> */
>>- if (dma_pe_count > phb->ioda.tce32_count)
>>- residual = 0;
>>- else
>>- residual = phb->ioda.tce32_count - dma_pe_count;
>>-
>>- pr_info("PCI: Domain %04x has %ld available 32-bit DMA segments\n",
>>- hose->global_number, phb->ioda.tce32_count);
>>- pr_info("PCI: %d PE# for a total weight of %d\n",
>>- dma_pe_count, total_weight);
>>+ pr_info("PCI: Domain %04x has %d available 32-bit DMA segments\n",
>>+ hose->global_number, phb->ioda.dma32_count);
>>
>> pnv_pci_ioda_setup_opal_tce_kill(phb);
>>
>>- /* Walk our PE list and configure their DMA segments, hand them
>>- * out one base segment plus any residual segments based on
>>- * weight
>>- */
>>- remaining = phb->ioda.tce32_count;
>>- base = 0;
>>+ /* Walk our PE list and configure their DMA segments */
>> list_for_each_entry(pe, &phb->ioda.pe_list, list) {
>> weight = pnv_pci_ioda_pe_dma_weight(pe);
>> if (!weight)
>> continue;
>>
>>- if (!remaining) {
>>- pe_warn(pe, "No DMA32 resources available\n");
>>- continue;
>>- }
>>- segs = 1;
>>- if (residual) {
>>- segs += ((weight * residual) + (total_weight / 2)) /
>>- total_weight;
>>- if (segs > remaining)
>>- segs = remaining;
>>- }
>>-
>> /*
>> * For IODA2 compliant PHB3, we needn't care about the weight.
>> * The all available 32-bits DMA space will be assigned to
>> * the specific PE.
>> */
>> if (phb->type == PNV_PHB_IODA1) {
>>- pe_info(pe, "DMA weight %d, assigned %d DMA32 segments\n",
>>- weight, segs);
>>- pnv_pci_ioda1_setup_dma_pe(phb, pe, base, segs);
>>+ pnv_pci_ioda1_setup_dma_pe(phb, pe);
>> } else if (phb->type == PNV_PHB_IODA2) {
>> pe_info(pe, "Assign DMA32 space\n");
>>- segs = 0;
>> pnv_pci_ioda2_setup_dma_pe(phb, pe);
>> } else if (phb->type == PNV_PHB_NPU) {
>> /*
>>@@ -2618,9 +2613,6 @@ static void pnv_ioda_setup_dma(struct pnv_phb *phb)
>> * as the PHB3 TVT.
>> */
>> }
>>-
>>- remaining -= segs;
>>- base += segs;
>> }
>> }
>>
>>@@ -3327,7 +3319,8 @@ static void __init pnv_pci_init_ioda_phb(struct device_node *np,
>> {
>> struct pci_controller *hose;
>> struct pnv_phb *phb;
>>- unsigned long size, m64map_off, m32map_off, pemap_off, iomap_off = 0;
>>+ unsigned long size, m64map_off, m32map_off, pemap_off;
>>+ unsigned long iomap_off = 0, dma32map_off = 0;
>> const __be64 *prop64;
>> const __be32 *prop32;
>> int len;
>>@@ -3413,6 +3406,10 @@ static void __init pnv_pci_init_ioda_phb(struct device_node *np,
>> phb->ioda.io_segsize = phb->ioda.io_size / phb->ioda.total_pe_num;
>> phb->ioda.io_pci_base = 0; /* XXX calculate this ? */
>>
>>+ /* Calculate how many 32-bit TCE segments we have */
>>+ phb->ioda.dma32_count = phb->ioda.m32_pci_base /
>>+ PNV_IODA1_DMA32_SEGSIZE;
>>+
>> /* Allocate aux data & arrays. We don't have IO ports on PHB3 */
>> size = _ALIGN_UP(phb->ioda.total_pe_num / 8, sizeof(unsigned long));
>> m64map_off = size;
>>@@ -3422,6 +3419,9 @@ static void __init pnv_pci_init_ioda_phb(struct device_node *np,
>> if (phb->type == PNV_PHB_IODA1) {
>> iomap_off = size;
>> size += phb->ioda.total_pe_num * sizeof(phb->ioda.io_segmap[0]);
>>+ dma32map_off = size;
>>+ size += phb->ioda.dma32_count *
>>+ sizeof(phb->ioda.dma32_segmap[0]);
>> }
>> pemap_off = size;
>> size += phb->ioda.total_pe_num * sizeof(struct pnv_ioda_pe);
>>@@ -3437,6 +3437,10 @@ static void __init pnv_pci_init_ioda_phb(struct device_node *np,
>> phb->ioda.io_segmap = aux + iomap_off;
>> for (segno = 0; segno < phb->ioda.total_pe_num; segno++)
>> phb->ioda.io_segmap[segno] = IODA_INVALID_PE;
>>+
>>+ phb->ioda.dma32_segmap = aux + dma32map_off;
>>+ for (segno = 0; segno < phb->ioda.dma32_count; segno++)
>>+ phb->ioda.dma32_segmap[segno] = IODA_INVALID_PE;
>> }
>> phb->ioda.pe_array = aux + pemap_off;
>> set_bit(phb->ioda.reserved_pe_idx, phb->ioda.pe_alloc);
>>@@ -3445,7 +3449,7 @@ 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 /
>>+ phb->ioda.dma32_count = phb->ioda.m32_pci_base /
>> PNV_IODA1_DMA32_SEGSIZE;
>>
>> #if 0 /* We should really do that ... */
>>diff --git a/arch/powerpc/platforms/powernv/pci.h b/arch/powerpc/platforms/powernv/pci.h
>>index 117cfcd..14d9391 100644
>>--- a/arch/powerpc/platforms/powernv/pci.h
>>+++ b/arch/powerpc/platforms/powernv/pci.h
>>@@ -142,6 +142,10 @@ struct pnv_phb {
>> unsigned int *m32_segmap;
>> unsigned int *io_segmap;
>>
>>+ /* DMA32 segment maps - IODA1 only */
>>+ unsigned int dma32_count;
>>+ unsigned int *dma32_segmap;
>>+
>> /* IRQ chip */
>> int irq_chip_init;
>> struct irq_chip irq_chip;
>>@@ -158,9 +162,6 @@ struct pnv_phb {
>> */
>> unsigned char pe_rmap[0x10000];
>>
>>- /* 32-bit TCE tables allocation */
>>- unsigned long tce32_count;
>>-
>> /* TCE cache invalidate registers (physical and
>> * remapped)
>> */
>>--
>>2.1.0
>>
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