A set of cache operations (both invalidation and flush) were redundant in the S3C HS OTG Samsung driver.
Test condition - test HW + measurement: Trats - Exynos4210 rev.1 - test HW Trats2 - Exynos4412 rev.1 400 MiB compressed rootfs image download with `thor 0 mmc 0`
Measurements:
Base values (without improvement): Transmission speed: 9.51 MiB/s
After the change: Transmission speed: 10.15 MiB/s
Change-Id: I0d55da4de724b14e988fefdb37a012562f7da8a2 Signed-off-by: Lukasz Majewski l.majewski@samsung.com Cc: Marek Vasut marex@denx.de --- drivers/usb/gadget/s3c_udc_otg_xfer_dma.c | 13 ------------- 1 file changed, 13 deletions(-)
diff --git a/drivers/usb/gadget/s3c_udc_otg_xfer_dma.c b/drivers/usb/gadget/s3c_udc_otg_xfer_dma.c index 1cbf8f6..eaa3a20 100644 --- a/drivers/usb/gadget/s3c_udc_otg_xfer_dma.c +++ b/drivers/usb/gadget/s3c_udc_otg_xfer_dma.c @@ -29,10 +29,6 @@ static inline void s3c_udc_ep0_zlp(struct s3c_udc *dev) { u32 ep_ctrl;
- flush_dcache_range((unsigned long) usb_ctrl_dma_addr, - (unsigned long) usb_ctrl_dma_addr - + DMA_BUFFER_SIZE); - writel(usb_ctrl_dma_addr, ®->in_endp[EP0_CON].diepdma); writel(DIEPT_SIZ_PKT_CNT(1), ®->in_endp[EP0_CON].dieptsiz);
@@ -52,10 +48,6 @@ void s3c_udc_pre_setup(void) debug_cond(DEBUG_IN_EP, "%s : Prepare Setup packets.\n", __func__);
- invalidate_dcache_range((unsigned long) usb_ctrl_dma_addr, - (unsigned long) usb_ctrl_dma_addr - + DMA_BUFFER_SIZE); - writel(DOEPT_SIZ_PKT_CNT(1) | sizeof(struct usb_ctrlrequest), ®->out_endp[EP0_CON].doeptsiz); writel(usb_ctrl_dma_addr, ®->out_endp[EP0_CON].doepdma); @@ -115,11 +107,6 @@ static int setdma_rx(struct s3c_ep *ep, struct s3c_request *req) ep->len = length; ep->dma_buf = buf;
- invalidate_dcache_range((unsigned long) ep->dev->dma_buf[ep_num], - (unsigned long) ep->dev->dma_buf[ep_num] - + ROUND(ep->ep.maxpacket, - CONFIG_SYS_CACHELINE_SIZE)); - if (length == 0) pktcnt = 1; else