[PATCH 17/29] ioat: preserve chanctrl bits when re-arming interrupts
From: Dan Williams <hidden>
Date: 2009-09-04 02:31:58
Also in:
linux-raid, lkml
Subsystem:
dma generic offload engine subsystem, intel i/oat dma driver, the rest · Maintainers:
Vinod Koul, Dave Jiang, Linus Torvalds
The register write in ioat_dma_cleanup_tasklet is unfortunate in two ways: 1/ It clears the extra 'enable' bits that we set at alloc_chan_resources time 2/ It gives the impression that it disables interrupts when it is in fact re-arming interrupts [ Impact: fix, persist the value of the chanctrl register when re-arming ] Signed-off-by: Maciej Sosnowski <redacted> Signed-off-by: Dan Williams <redacted> --- drivers/dma/ioat/dma.c | 10 +++------- drivers/dma/ioat/dma_v2.c | 8 ++------ drivers/dma/ioat/registers.h | 6 +++++- 3 files changed, 10 insertions(+), 14 deletions(-)
diff --git a/drivers/dma/ioat/dma.c b/drivers/dma/ioat/dma.c
index 5173ba9..6dd0af1 100644
--- a/drivers/dma/ioat/dma.c
+++ b/drivers/dma/ioat/dma.c@@ -452,7 +452,6 @@ static int ioat1_dma_alloc_chan_resources(struct dma_chan *c) struct ioat_dma_chan *ioat = to_ioat_chan(c); struct ioat_chan_common *chan = &ioat->base; struct ioat_desc_sw *desc; - u16 chanctrl; u32 chanerr; int i; LIST_HEAD(tmp_list);
@@ -462,10 +461,7 @@ static int ioat1_dma_alloc_chan_resources(struct dma_chan *c) return ioat->desccount; /* Setup register to interrupt and write completion status on error */ - chanctrl = IOAT_CHANCTRL_ERR_INT_EN | - IOAT_CHANCTRL_ANY_ERR_ABORT_EN | - IOAT_CHANCTRL_ERR_COMPLETION_EN; - writew(chanctrl, chan->reg_base + IOAT_CHANCTRL_OFFSET); + writew(IOAT_CHANCTRL_RUN, chan->reg_base + IOAT_CHANCTRL_OFFSET); chanerr = readl(chan->reg_base + IOAT_CHANERR_OFFSET); if (chanerr) {
@@ -672,9 +668,9 @@ ioat1_dma_prep_memcpy(struct dma_chan *c, dma_addr_t dma_dest, static void ioat1_cleanup_tasklet(unsigned long data) { struct ioat_dma_chan *chan = (void *)data; + ioat1_cleanup(chan); - writew(IOAT_CHANCTRL_INT_DISABLE, - chan->base.reg_base + IOAT_CHANCTRL_OFFSET); + writew(IOAT_CHANCTRL_RUN, chan->base.reg_base + IOAT_CHANCTRL_OFFSET); } static void ioat_unmap(struct pci_dev *pdev, dma_addr_t addr, size_t len,
diff --git a/drivers/dma/ioat/dma_v2.c b/drivers/dma/ioat/dma_v2.c
index 589bbc3..be617db 100644
--- a/drivers/dma/ioat/dma_v2.c
+++ b/drivers/dma/ioat/dma_v2.c@@ -342,8 +342,7 @@ static void ioat2_cleanup_tasklet(unsigned long data) struct ioat2_dma_chan *ioat = (void *) data; ioat2_cleanup(ioat); - writew(IOAT_CHANCTRL_INT_DISABLE, - ioat->base.reg_base + IOAT_CHANCTRL_OFFSET); + writew(IOAT_CHANCTRL_RUN, ioat->base.reg_base + IOAT_CHANCTRL_OFFSET); } /**
@@ -455,7 +454,6 @@ static int ioat2_alloc_chan_resources(struct dma_chan *c) struct ioat2_dma_chan *ioat = to_ioat2_chan(c); struct ioat_chan_common *chan = &ioat->base; struct ioat_ring_ent **ring; - u16 chanctrl; u32 chanerr; int descs; int i;
@@ -465,9 +463,7 @@ static int ioat2_alloc_chan_resources(struct dma_chan *c) return 1 << ioat->alloc_order; /* Setup register to interrupt and write completion status on error */ - chanctrl = IOAT_CHANCTRL_ERR_INT_EN | IOAT_CHANCTRL_ANY_ERR_ABORT_EN | - IOAT_CHANCTRL_ERR_COMPLETION_EN; - writew(chanctrl, chan->reg_base + IOAT_CHANCTRL_OFFSET); + writew(IOAT_CHANCTRL_RUN, chan->reg_base + IOAT_CHANCTRL_OFFSET); chanerr = readl(chan->reg_base + IOAT_CHANERR_OFFSET); if (chanerr) {
diff --git a/drivers/dma/ioat/registers.h b/drivers/dma/ioat/registers.h
index a83c733..4380f6f 100644
--- a/drivers/dma/ioat/registers.h
+++ b/drivers/dma/ioat/registers.h@@ -75,7 +75,11 @@ #define IOAT_CHANCTRL_ERR_INT_EN 0x0010 #define IOAT_CHANCTRL_ANY_ERR_ABORT_EN 0x0008 #define IOAT_CHANCTRL_ERR_COMPLETION_EN 0x0004 -#define IOAT_CHANCTRL_INT_DISABLE 0x0001 +#define IOAT_CHANCTRL_INT_REARM 0x0001 +#define IOAT_CHANCTRL_RUN (IOAT_CHANCTRL_INT_REARM |\ + IOAT_CHANCTRL_ERR_COMPLETION_EN |\ + IOAT_CHANCTRL_ANY_ERR_ABORT_EN |\ + IOAT_CHANCTRL_ERR_INT_EN) #define IOAT_DMA_COMP_OFFSET 0x02 /* 16-bit DMA channel compatibility */ #define IOAT_DMA_COMP_V1 0x0001 /* Compatibility with DMA version 1 */