[PATCH 2.6.18-rc1-mm2 3/6] ieee1394: sbp2: optimize DMA direction of command ORBs

[PATCH 2.6.18-rc1-mm2 3/6] ieee1394: sbp2: optimize DMA direction of command ORBs

Post by Stefan Ric » Tue, 25 Jul 2006 06:00:07


nly the driver writes ORBs, the device just reads them. Therefore
PCI_DMA_BIDIRECTIONAL can be replaced by PCI_DMA_TODEVICE which may be
cheaper on some architectures.

Signed-off-by: Stefan Richter < XXXX@XXXXX.COM >
---
drivers/ieee1394/sbp2.c | 16 ++++++++--------
1 files changed, 8 insertions(+), 8 deletions(-)

TODO:
Convert sbp2 from PCI DMA to generic DMA mapping.

Index: linux/drivers/ieee1394/sbp2.c
===================================================================
--- linux.orig/drivers/ieee1394/sbp2.c 2006-07-23 10:16:57.000000000 +0200
+++ linux/drivers/ieee1394/sbp2.c 2006-07-23 10:19:29.000000000 +0200
@@ -492,7 +492,7 @@ static int sbp2util_create_command_orb_p
command->command_orb_dma =
pci_map_single(hi->host->pdev, &command->command_orb,
sizeof(struct sbp2_command_orb),
- PCI_DMA_BIDIRECTIONAL);
+ PCI_DMA_TODEVICE);
SBP2_DMA_ALLOC("single command orb DMA");
command->sge_dma =
pci_map_single(hi->host->pdev,
@@ -525,7 +525,7 @@ static void sbp2util_remove_command_orb_
/* Release our generic DMA's */
pci_unmap_single(host->pdev, command->command_orb_dma,
sizeof(struct sbp2_command_orb),
- PCI_DMA_BIDIRECTIONAL);
+ PCI_DMA_TODEVICE);
SBP2_DMA_FREE("single command orb DMA");
pci_unmap_single(host->pdev, command->sge_dma,
sizeof(command->scatter_gather_element),
@@ -1982,7 +1982,7 @@ static void sbp2_link_orb_command(struct

pci_dma_sync_single_for_device(hi->host->pdev, command->command_orb_dma,
sizeof(struct sbp2_command_orb),
- PCI_DMA_BIDIRECTIONAL);
+ PCI_DMA_TODEVICE);
pci_dma_sync_single_for_device(hi->host->pdev, command->sge_dma,
sizeof(command->scatter_gather_element),
PCI_DMA_BIDIRECTIONAL);
@@ -2012,14 +2012,14 @@ static void sbp2_link_orb_command(struct
*/
pci_dma_sync_single_for_cpu(hi->host->pdev, last_orb_dma,
sizeof(struct sbp2_command_orb),
- PCI_DMA_BIDIRECTIONAL);
+ PCI_DMA_TODEVICE);
last_orb->next_ORB_lo = cpu_to_be32(command->command_orb_dma);
wmb();
/* Tells hardware that this pointer is valid */
last_orb->next_ORB_hi = 0;
pci_dma_sync_single_for_device(hi->host->pdev, last_orb_dma,
sizeof(struct sbp2_command_orb),
- PCI_DMA_BIDIRECTIONAL);
+ PCI_DMA_TODEVICE);
addr += SBP2_DOORBELL_OFFSET;
data[0] = 0;
length = 4;
@@ -2176,7 +2176,7 @@ static int sbp2_handle_status_write(stru
SBP2_DEBUG("Found status for command ORB");
pci_dma_sync_single_for_cpu(hi->host->pdev, command->command_orb_dma,
sizeof(struct sbp2_command_orb),
- PCI_DMA_BIDIRECTIONAL);
+ PCI_DMA_TODEVICE);
pci_dma_sync_single_for_cpu(hi->host->pdev, command->sge_dma,
sizeof(command->scatter_gather_element),
PCI_DMA_BIDIRECTIONAL);
@@ -2365,7 +2365,7 @@ static void sbp2scsi_complete_all_comman
command = list_entry(lh, struct sbp2_command_info, list);
pci_dma_sync_single_for_cpu(hi->host->pdev, command->command_orb_dma,
sizeof(struct sbp2_command_orb),
- PCI_DMA_BIDIRECTIONAL);
+ PCI_DMA_TODEVICE);
pci_dma_sync_single_for_cpu(hi->host->pdev, command->sge_dma,
sizeof(command->scatter_gather_element),