[PATCH kernel v9 23/32] powerpc/powernv/ioda: Define and implement DMA table/window management callbacks

Alexey Kardashevskiy
2015-04-25T12:17:11Z

This extends iommu_table_group_ops by a set of callbacks to support
dynamic DMA windows management.

create_table() creates a TCE table with specific parameters.
it receives iommu_table_group to know nodeid in order to allocate
TCE table memory closer to the PHB. The exact format of allocated
multi-level table might be also specific to the PHB model (not
the case now though).
This callback calculated the DMA window offset on a PCI bus from @num
and stores it in a just created table.

set_window() sets the window at specified TVT index + @num on PHB.

unset_window() unsets the window from specified TVT.

This adds a free() callback to iommu_table_ops to free the memory
(potentially a tree of tables) allocated for the TCE table.

create_table() and free() are supposed to be called once per
VFIO container and set_window()/unset_window() are supposed to be
called for every group in a container.

This adds IOMMU capabilities to iommu_table_group such as default
32bit window parameters and others.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
---
arch/powerpc/include/asm/iommu.h | 19 ++++++++
arch/powerpc/platforms/powernv/pci-ioda.c | 75 ++++++++++++++++++++++++++---
arch/powerpc/platforms/powernv/pci-p5ioc2.c | 12 +++--
3 files changed, 96 insertions(+), 10 deletions(-)

diff --git a/arch/powerpc/include/asm/iommu.h b/arch/powerpc/include/asm/iommu.h
index 0f50ee2..7694546 100644
--- a/arch/powerpc/include/asm/iommu.h
+++ b/arch/powerpc/include/asm/iommu.h
@@ -70,6 +70,7 @@ struct iommu_table_ops {
/* get() returns a physical address */
unsigned long (*get)(struct iommu_table *tbl, long index);
void (*flush)(struct iommu_table *tbl);
+ void (*free)(struct iommu_table *tbl);
};

/* These are used by VIO */
@@ -148,6 +149,17 @@ extern struct iommu_table *iommu_init_table(struct iommu_table * tbl,
struct iommu_table_group;

struct iommu_table_group_ops {
+ long (*create_table)(struct iommu_table_group *table_group,
+ int num,
+ __u32 page_shift,
+ __u64 window_size,
+ __u32 levels,
+ struct iommu_table *tbl);
+ long (*set_window)(struct iommu_table_group *table_group,
+ int num,
+ struct iommu_table *tblnew);
+ long (*unset_window)(struct iommu_table_group *table_group,
+ int num);
/*
* Switches ownership from the kernel itself to an external
* user. While onwership is taken, the kernel cannot use IOMMU itself.
@@ -160,6 +172,13 @@ struct iommu_table_group {
#ifdef CONFIG_IOMMU_API
struct iommu_group *group;
#endif
+ /* Some key properties of IOMMU */
+ __u32 tce32_start;
+ __u32 tce32_size;
+ __u64 pgsizes; /* Bitmap of supported page sizes */
+ __u32 max_dynamic_windows_supported;
+ __u32 max_levels;
+
struct iommu_table tables[IOMMU_TABLE_GROUP_MAX_TABLES];
struct iommu_table_group_ops *ops;
};
diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index cc1d09c..4828837 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -24,6 +24,7 @@
#include <linux/msi.h>
#include <linux/memblock.h>
#include <linux/iommu.h>
+#include <linux/sizes.h>

#include <asm/sections.h>
#include <asm/io.h>
@@ -1846,6 +1847,7 @@ static struct iommu_table_ops pnv_ioda2_iommu_ops = {
#endif
.clear = pnv_ioda2_tce_free,
.get = pnv_tce_get,
+ .free = pnv_pci_free_table,
};

static void pnv_pci_ioda_setup_opal_tce_kill(struct pnv_phb *phb,
@@ -1936,6 +1938,8 @@ static void pnv_pci_ioda_setup_dma_pe(struct pnv_phb *phb,
TCE_PCI_SWINV_PAIR);

tbl->it_ops = &pnv_ioda1_iommu_ops;
+ pe->table_group.tce32_start = tbl->it_offset << tbl->it_page_shift;
+ pe->table_group.tce32_size = tbl->it_size << tbl->it_page_shift;
iommu_init_table(tbl, phb->hose->node);

if (pe->flags & PNV_IODA_PE_DEV) {
@@ -1961,7 +1965,7 @@ static void pnv_pci_ioda_setup_dma_pe(struct pnv_phb *phb,
}

static long pnv_pci_ioda2_set_window(struct iommu_table_group *table_group,
- struct iommu_table *tbl)
+ int num, struct iommu_table *tbl)
{
struct pnv_ioda_pe *pe = container_of(table_group, struct pnv_ioda_pe,
table_group);
@@ -1972,9 +1976,10 @@ static long pnv_pci_ioda2_set_window(struct iommu_table_group *table_group,
const __u64 start_addr = tbl->it_offset << tbl->it_page_shift;
const __u64 win_size = tbl->it_size << tbl->it_page_shift;

- pe_info(pe, "Setting up window at %llx..%llx "
+ pe_info(pe, "Setting up window#%d at %llx..%llx "
"pgsize=0x%x tablesize=0x%lx "
"levels=%d levelsize=%x\n",
+ num,
start_addr, start_addr + win_size - 1,
1UL << tbl->it_page_shift, tbl->it_size << 3,
tbl->it_indirect_levels + 1, tbl->it_level_size << 3);
@@ -1987,7 +1992,7 @@ static long pnv_pci_ioda2_set_window(struct iommu_table_group *table_group,
*/
rc = opal_pci_map_pe_dma_window(phb->opal_id,
pe->pe_number,
- pe->pe_number << 1,
+ (pe->pe_number << 1) + num,
tbl->it_indirect_levels + 1,
__pa(tbl->it_base),
size << 3,
@@ -2000,7 +2005,7 @@ static long pnv_pci_ioda2_set_window(struct iommu_table_group *table_group,
pnv_pci_ioda2_tvt_invalidate(pe);

/* Store fully initialized *tbl (may be external) in PE */
- pe->table_group.tables[0] = *tbl;
+ pe->table_group.tables[num] = *tbl;

return 0;
fail:
@@ -2061,6 +2066,53 @@ static void pnv_pci_ioda2_setup_bypass_pe(struct pnv_phb *phb,
}

#ifdef CONFIG_IOMMU_API
+static long pnv_pci_ioda2_create_table(struct iommu_table_group *table_group,
+ int num, __u32 page_shift, __u64 window_size, __u32 levels,
+ struct iommu_table *tbl)
+{
+ struct pnv_ioda_pe *pe = container_of(table_group, struct pnv_ioda_pe,
+ table_group);
+ int nid = pe->phb->hose->node;
+ __u64 bus_offset = num ? pe->tce_bypass_base : 0;
+ long ret;
+
+ ret = pnv_pci_create_table(table_group, nid, bus_offset, page_shift,
+ window_size, levels, tbl);
+ if (ret)
+ return ret;
+
+ tbl->it_ops = &pnv_ioda2_iommu_ops;
+ if (pe->tce_inval_reg)
+ tbl->it_type |= (TCE_PCI_SWINV_CREATE | TCE_PCI_SWINV_FREE);
+
+ return 0;
+}
+
+static long pnv_pci_ioda2_unset_window(struct iommu_table_group *table_group,
+ int num)
+{
+ struct pnv_ioda_pe *pe = container_of(table_group, struct pnv_ioda_pe,
+ table_group);
+ struct pnv_phb *phb = pe->phb;
+ struct iommu_table *tbl = &pe->table_group.tables[num];
+ long ret;
+
+ pe_info(pe, "Removing DMA window #%d\n", num);
+
+ ret = opal_pci_map_pe_dma_window(phb->opal_id, pe->pe_number,
+ (pe->pe_number << 1) + num,
+ 0/* levels */, 0/* table address */,
+ 0/* table size */, 0/* page size */);
+ if (ret)
+ pe_warn(pe, "Unmapping failed, ret = %ld\n", ret);
+ else
+ pnv_pci_ioda2_tvt_invalidate(pe);
+
+ memset(tbl, 0, sizeof(*tbl));
+
+ return ret;
+}
+
static void pnv_ioda2_take_ownership(struct iommu_table_group *table_group)
{
struct pnv_ioda_pe *pe = container_of(table_group, struct pnv_ioda_pe,
@@ -2080,6 +2132,9 @@ static void pnv_ioda2_release_ownership(struct iommu_table_group *table_group)
}

static struct iommu_table_group_ops pnv_pci_ioda2_ops = {
+ .create_table = pnv_pci_ioda2_create_table,
+ .set_window = pnv_pci_ioda2_set_window,
+ .unset_window = pnv_pci_ioda2_unset_window,
.take_ownership = pnv_ioda2_take_ownership,
.release_ownership = pnv_ioda2_release_ownership,
};
@@ -2102,8 +2157,16 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
pe_info(pe, "Setting up 32-bit TCE table at 0..%08x\n",
phb->ioda.m32_pci_base);

+ pe->table_group.tce32_start = 0;
+ pe->table_group.tce32_size = phb->ioda.m32_pci_base;
+ pe->table_group.max_dynamic_windows_supported =
+ IOMMU_TABLE_GROUP_MAX_TABLES;
+ pe->table_group.max_levels = POWERNV_IOMMU_MAX_LEVELS;
+ pe->table_group.pgsizes = SZ_4K | SZ_64K | SZ_16M;
+
rc = pnv_pci_create_table(&pe->table_group, pe->phb->hose->node,
- 0, IOMMU_PAGE_SHIFT_4K, phb->ioda.m32_pci_base,
+ pe->table_group.tce32_start, IOMMU_PAGE_SHIFT_4K,
+ pe->table_group.tce32_size,
POWERNV_IOMMU_DEFAULT_LEVELS, tbl);
if (rc) {
pe_err(pe, "Failed to create 32-bit TCE table, err %ld", rc);
@@ -2119,7 +2182,7 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
pe->table_group.ops = &pnv_pci_ioda2_ops;
#endif

- rc = pnv_pci_ioda2_set_window(&pe->table_group, tbl);
+ rc = pnv_pci_ioda2_set_window(&pe->table_group, 0, tbl);
if (rc) {
pe_err(pe, "Failed to configure 32-bit TCE table,"
" err %ld\n", rc);
diff --git a/arch/powerpc/platforms/powernv/pci-p5ioc2.c b/arch/powerpc/platforms/powernv/pci-p5ioc2.c
index 7a6fd92..d9de4c7 100644
--- a/arch/powerpc/platforms/powernv/pci-p5ioc2.c
+++ b/arch/powerpc/platforms/powernv/pci-p5ioc2.c
@@ -116,6 +116,8 @@ static void __init pnv_pci_init_p5ioc2_phb(struct device_node *np, u64 hub_id,
u64 phb_id;
int64_t rc;
static int primary = 1;
+ struct iommu_table_group *table_group;
+ struct iommu_table *tbl;

pr_info(" Initializing p5ioc2 PHB %s\n", np->full_name);

@@ -181,14 +183,16 @@ static void __init pnv_pci_init_p5ioc2_phb(struct device_node *np, u64 hub_id,
pnv_pci_init_p5ioc2_msis(phb);

/* Setup iommu */
- phb->p5ioc2.table_group.tables[0].it_table_group =
- &phb->p5ioc2.table_group;
+ table_group = &phb->p5ioc2.table_group;
+ tbl = &phb->p5ioc2.table_group.tables[0];
+ tbl->it_table_group = table_group;

/* Setup TCEs */
phb->dma_dev_setup = pnv_pci_p5ioc2_dma_dev_setup;
- pnv_pci_setup_iommu_table(&phb->p5ioc2.table_group.tables[0],
- tce_mem, tce_size, 0,
+ pnv_pci_setup_iommu_table(tbl, tce_mem, tce_size, 0,
IOMMU_PAGE_SHIFT_4K);
+ table_group->tce32_start = tbl->it_offset << tbl->it_page_shift;
+ table_group->tce32_size = tbl->it_size << tbl->it_page_shift;
}

void __init pnv_pci_init_p5ioc2_hub(struct device_node *np)
--
2.0.0