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@xxxxxxxxxxxxxxxxxx>
---
arch/powerpc/platforms/powernv/pci-ioda.c | 111 +++++++++++++++++-------------
arch/powerpc/platforms/powernv/pci.h | 7 +-
2 files changed, 66 insertions(+), 52 deletions(-)
diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index 0fc2309..59782fba 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -2007,20 +2007,54 @@ static unsigned int pnv_pci_ioda_total_dma_weight(struct pnv_phb *phb)
}
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;
+ 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 */
+ total_weight = pnv_pci_ioda_total_dma_weight(phb);
+ 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.
+ */
+ while (segs) {
+ 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)
+ break;
+ }
+
+ if (i >= base + segs)
+ break;
+ }
+
+ if (i >= base + segs)
+ break;
+
+ segs--;
+ }
+
+ if (!segs) {
+ pe_warn(pe, "No available DMA32 segments\n");
+ return;
+ }
tbl = pnv_pci_table_alloc(phb->hose->node);
iommu_register_group(&pe->table_group, phb->hose->global_number,
@@ -2028,6 +2062,8 @@ static void pnv_pci_ioda1_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_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);
@@ -2064,6 +2100,10 @@ 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,
@@ -2538,70 +2578,34 @@ 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 = pnv_pci_ioda_total_dma_weight(phb);
- 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);
+ 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) {
/*
@@ -2611,9 +2615,6 @@ static void pnv_ioda_setup_dma(struct pnv_phb *phb)
* as the PHB3 TVT.
*/
}
-
- remaining -= segs;
- base += segs;
}
}
@@ -3313,7 +3314,8 @@ 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 i, len;
@@ -3398,6 +3400,10 @@ 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;
@@ -3407,6 +3413,9 @@ 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);
@@ -3422,6 +3431,10 @@ static void __init pnv_pci_init_ioda_phb(struct device_node *np,
phb->ioda.io_segmap = aux + iomap_off;
for (i = 0; i < phb->ioda.total_pe_num; i++)
phb->ioda.io_segmap[i] = IODA_INVALID_PE;
+
+ phb->ioda.dma32_segmap = aux + dma32map_off;
+ for (i = 0; i < phb->ioda.dma32_count; i++)
+ phb->ioda.dma32_segmap[i] = IODA_INVALID_PE;
}
phb->ioda.pe_array = aux + pemap_off;
set_bit(phb->ioda.reserved_pe_idx, phb->ioda.pe_alloc);
@@ -3430,7 +3443,7 @@ 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 e90bcbe..350e630 100644
--- a/arch/powerpc/platforms/powernv/pci.h
+++ b/arch/powerpc/platforms/powernv/pci.h
@@ -146,6 +146,10 @@ struct pnv_phb {
int *m32_segmap;
int *io_segmap;
+ /* DMA32 segment maps - IODA1 only */
+ unsigned long dma32_count;
+ int *dma32_segmap;
+
/* IRQ chip */
int irq_chip_init;
struct irq_chip irq_chip;
@@ -162,9 +166,6 @@ 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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