diff options
| author | Hanna Hawa <hannah@marvell.com> | 2017-05-05 12:57:51 +0300 |
|---|---|---|
| committer | Vinod Koul <vinod.koul@intel.com> | 2017-05-14 15:54:45 +0300 |
| commit | d793327fac3a9292edfdcee0ab6c29e4fdd08d65 (patch) | |
| tree | ac10c236871c816f0537128e694d074827ef8de3 /drivers/dma | |
| parent | b2d3c270f9f2fb82518ac500a9849c3aaf503852 (diff) | |
| download | linux-d793327fac3a9292edfdcee0ab6c29e4fdd08d65.tar.xz | |
dmaengine: mv_xor_v2: implement proper interrupt coalescing
Until now, the driver was not using interrupt coalescing: one interrupt
was generated for each descriptor processed by the XOR engine. This
commit changes that by using the interrupt coalescing features of the
hardware, by setting both a number of descriptors processed before an
interrupt is generated and a timeout before an interrupt is generated.
Signed-off-by: Hanna Hawa <hannah@marvell.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Diffstat (limited to 'drivers/dma')
| -rw-r--r-- | drivers/dma/mv_xor_v2.c | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/drivers/dma/mv_xor_v2.c b/drivers/dma/mv_xor_v2.c index f3e211f8f6c5..5292ff2d5380 100644 --- a/drivers/dma/mv_xor_v2.c +++ b/drivers/dma/mv_xor_v2.c @@ -42,6 +42,7 @@ #define MV_XOR_V2_DMA_IMSG_THRD_OFF 0x018 #define MV_XOR_V2_DMA_IMSG_THRD_MASK 0x7FFF #define MV_XOR_V2_DMA_IMSG_THRD_SHIFT 0x0 +#define MV_XOR_V2_DMA_IMSG_TIMER_EN BIT(18) #define MV_XOR_V2_DMA_DESQ_AWATTR_OFF 0x01C /* Same flags as MV_XOR_V2_DMA_DESQ_ARATTR_OFF */ #define MV_XOR_V2_DMA_DESQ_ALLOC_OFF 0x04C @@ -55,6 +56,9 @@ #define MV_XOR_V2_DMA_DESQ_STOP_OFF 0x800 #define MV_XOR_V2_DMA_DESQ_DEALLOC_OFF 0x804 #define MV_XOR_V2_DMA_DESQ_ADD_OFF 0x808 +#define MV_XOR_V2_DMA_IMSG_TMOT 0x810 +#define MV_XOR_V2_DMA_IMSG_TIMER_THRD_MASK 0x1FFF +#define MV_XOR_V2_DMA_IMSG_TIMER_THRD_SHIFT 0 /* XOR Global registers */ #define MV_XOR_V2_GLOB_BW_CTRL 0x4 @@ -90,6 +94,13 @@ */ #define MV_XOR_V2_DESC_NUM 1024 +/* + * Threshold values for descriptors and timeout, determined by + * experimentation as giving a good level of performance. + */ +#define MV_XOR_V2_DONE_IMSG_THRD 0x14 +#define MV_XOR_V2_TIMER_THRD 0xB0 + /** * struct mv_xor_v2_descriptor - DMA HW descriptor * @desc_id: used by S/W and is not affected by H/W. @@ -246,6 +257,29 @@ static int mv_xor_v2_set_desc_size(struct mv_xor_v2_device *xor_dev) return MV_XOR_V2_EXT_DESC_SIZE; } +/* + * Set the IMSG threshold + */ +static inline +void mv_xor_v2_enable_imsg_thrd(struct mv_xor_v2_device *xor_dev) +{ + u32 reg; + + /* Configure threshold of number of descriptors, and enable timer */ + reg = readl(xor_dev->dma_base + MV_XOR_V2_DMA_IMSG_THRD_OFF); + reg &= (~MV_XOR_V2_DMA_IMSG_THRD_MASK << MV_XOR_V2_DMA_IMSG_THRD_SHIFT); + reg |= (MV_XOR_V2_DONE_IMSG_THRD << MV_XOR_V2_DMA_IMSG_THRD_SHIFT); + reg |= MV_XOR_V2_DMA_IMSG_TIMER_EN; + writel(reg, xor_dev->dma_base + MV_XOR_V2_DMA_IMSG_THRD_OFF); + + /* Configure Timer Threshold */ + reg = readl(xor_dev->dma_base + MV_XOR_V2_DMA_IMSG_TMOT); + reg &= (~MV_XOR_V2_DMA_IMSG_TIMER_THRD_MASK << + MV_XOR_V2_DMA_IMSG_TIMER_THRD_SHIFT); + reg |= (MV_XOR_V2_TIMER_THRD << MV_XOR_V2_DMA_IMSG_TIMER_THRD_SHIFT); + writel(reg, xor_dev->dma_base + MV_XOR_V2_DMA_IMSG_TMOT); +} + static irqreturn_t mv_xor_v2_interrupt_handler(int irq, void *data) { struct mv_xor_v2_device *xor_dev = data; @@ -795,6 +829,8 @@ static int mv_xor_v2_probe(struct platform_device *pdev) list_add_tail(&xor_dev->dmachan.device_node, &dma_dev->channels); + mv_xor_v2_enable_imsg_thrd(xor_dev); + mv_xor_v2_descq_init(xor_dev); ret = dma_async_device_register(dma_dev); |