On 04/14/2016 09:54 AM, Gavin Shan wrote:
On Wed, Apr 13, 2016 at 06:29:42PM +1000, Alexey Kardashevskiy wrote:
On 02/17/2016 02:43 PM, Gavin Shan wrote:
Currently, there is one macro (TCE32_TABLE_SIZE) representing the
TCE table size for one DMA32 segment. The constant representing
the DMA32 segment size (1 << 28) is still used in the code.
This defines PNV_IODA1_DMA32_SEGSIZE representing one DMA32
segment size. the TCE table size can be calcualted when the page
s/calcualted/calculated/
has fixed 4KB size. So all the related calculation depends on one
macro (PNV_IODA1_DMA32_SEGSIZE). No logical changes introduced.
Please move PNV_IODA1_DMA32_SEGSIZE where TCE32_TABLE_SIZE was.
Signed-off-by: Gavin Shan <gwshan@xxxxxxxxxxxxxxxxxx>
---
arch/powerpc/platforms/powernv/pci-ioda.c | 30 +++++++++++++++++-------------
arch/powerpc/platforms/powernv/pci.h | 1 +
2 files changed, 18 insertions(+), 13 deletions(-)
diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index d18b95e..e60cff6 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -48,9 +48,6 @@
#include "powernv.h"
#include "pci.h"
-/* 256M DMA window, 4K TCE pages, 8 bytes TCE */
-#define TCE32_TABLE_SIZE ((0x10000000 / 0x1000) * 8)
-
#define POWERNV_IOMMU_DEFAULT_LEVELS 1
#define POWERNV_IOMMU_MAX_LEVELS 5
@@ -2034,7 +2031,7 @@ static void pnv_pci_ioda1_setup_dma_pe(struct pnv_phb *phb,
struct page *tce_mem = NULL;
struct iommu_table *tbl;
- unsigned int i;
+ unsigned int tce32_segsz, i;
PNV_IODA1_DMA32_SEGSIZE is a segment size in bytes. The name @tce32_segsz
also suggests that it is a segment size in bytes (otherwise it would be
tce32_seg_entries or something like this) but it is not, it is a number of
TCE entries (arch/powerpc/kernel/iommu.c uses "entry" for these). And
tce32_segsz never changes. So:
const unsigned int entries = PNV_IODA1_DMA32_SEGSIZE >> (IOMMU_PAGE_SHIFT_4K
- 3);
Are you sure @tce32_segsz and equation you gave are for number of TCE entries,
not the size of meory required for the DMA32 segment TCE table?
No, I am not :) "-3" makes it a table size in bytes, so it is rather
tablesz then.
int64_t rc;
void *addr;
@@ -2054,29 +2051,34 @@ static void pnv_pci_ioda1_setup_dma_pe(struct pnv_phb *phb,
/* Grab a 32-bit TCE table */
pe->tce32_seg = base;
pe_info(pe, " Setting up 32-bit TCE table at %08x..%08x\n",
- (base << 28), ((base + segs) << 28) - 1);
+ base * PNV_IODA1_DMA32_SEGSIZE,
+ (base + segs) * PNV_IODA1_DMA32_SEGSIZE - 1);
/* XXX Currently, we allocate one big contiguous table for the
* TCEs. We only really need one chunk per 256M of TCE space
* (ie per segment) but that's an optimization for later, it
* requires some added smarts with our get/put_tce implementation
+ *
+ * Each TCE page is 4KB in size and each TCE entry occupies 8
+ * bytes
*/
+ tce32_segsz = PNV_IODA1_DMA32_SEGSIZE >> (IOMMU_PAGE_SHIFT_4K - 3);
tce_mem = alloc_pages_node(phb->hose->node, GFP_KERNEL,
- get_order(TCE32_TABLE_SIZE * segs));
+ get_order(tce32_segsz * segs));
if (!tce_mem) {
pe_err(pe, " Failed to allocate a 32-bit TCE memory\n");
goto fail;
}
addr = page_address(tce_mem);
- memset(addr, 0, TCE32_TABLE_SIZE * segs);
+ memset(addr, 0, tce32_segsz * segs);
/* Configure HW */
for (i = 0; i < segs; i++) {
rc = opal_pci_map_pe_dma_window(phb->opal_id,
pe->pe_number,
base + i, 1,
- __pa(addr) + TCE32_TABLE_SIZE * i,
- TCE32_TABLE_SIZE, 0x1000);
+ __pa(addr) + tce32_segsz * i,
+ tce32_segsz, 0x1000);
As you started using IOMMU_PAGE_SHIFT_4K and you are also touching this piece
of code -
s/0x1000/IOMMU_PAGE_SHIFT_4K/
Does 0x1000 is equal to IOMMU_PAGE_SHIFT_4K? I guess you probably suggested
to use IOMMU_PAGE_SIZE_4K instead?
Ah, my bad, should have been IOMMU_PAGE_SIZE_4K. I'll pay more attention to
the details, sorry.
if (rc) {
pe_err(pe, " Failed to configure 32-bit TCE table,"
" err %ld\n", rc);
@@ -2085,8 +2087,9 @@ static void pnv_pci_ioda1_setup_dma_pe(struct pnv_phb *phb,
}
/* Setup linux iommu table */
- pnv_pci_setup_iommu_table(tbl, addr, TCE32_TABLE_SIZE * segs,
- base << 28, IOMMU_PAGE_SHIFT_4K);
+ pnv_pci_setup_iommu_table(tbl, addr, tce32_segsz * segs,
+ base * PNV_IODA1_DMA32_SEGSIZE,
+ IOMMU_PAGE_SHIFT_4K);
/* OPAL variant of P7IOC SW invalidated TCEs */
if (phb->ioda.tce_inval_reg)
@@ -2116,7 +2119,7 @@ static void pnv_pci_ioda1_setup_dma_pe(struct pnv_phb *phb,
if (pe->tce32_seg >= 0)
pe->tce32_seg = -1;
if (tce_mem)
- __free_pages(tce_mem, get_order(TCE32_TABLE_SIZE * segs));
+ __free_pages(tce_mem, get_order(tce32_segsz * segs));
if (tbl) {
pnv_pci_unlink_table_and_group(tbl, &pe->table_group);
iommu_free_table(tbl, "pnv");
@@ -3445,7 +3448,8 @@ 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.tce32_count = phb->ioda.m32_pci_base /
+ PNV_IODA1_DMA32_SEGSIZE;
#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 00539ff..1d8e775 100644
--- a/arch/powerpc/platforms/powernv/pci.h
+++ b/arch/powerpc/platforms/powernv/pci.h
@@ -84,6 +84,7 @@ struct pnv_ioda_pe {
#define PNV_IODA1_M64_NUM 16 /* Number of M64 BARs */
#define PNV_IODA1_M64_SEGS 8 /* Segments per M64 BAR */
+#define PNV_IODA1_DMA32_SEGSIZE 0x10000000
#define PNV_PHB_FLAG_EEH (1 << 0)
--
Alexey
--
Alexey
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
