From 4a4863bf2e7932e584a3a462d3c6daf891142ddc Mon Sep 17 00:00:00 2001 From: Martin Schiller Date: Mon, 18 Feb 2019 07:37:30 +0100 Subject: usb: dwc2: Fix DMA cache alignment issues Insert a padding between data and the stored_xfer_buffer pointer to ensure they are not on the same cache line. Otherwise, the stored_xfer_buffer gets corrupted for IN URBs on non-cache-coherent systems. (In my case: Lantiq xRX200 MIPS) Fixes: 3bc04e28a030 ("usb: dwc2: host: Get aligned DMA in a more supported way") Fixes: 56406e017a88 ("usb: dwc2: Fix DMA alignment to start at allocated boundary") Cc: Tested-by: Douglas Anderson Reviewed-by: Douglas Anderson Acked-by: Minas Harutyunyan Signed-off-by: Martin Schiller Signed-off-by: Felipe Balbi --- drivers/usb/dwc2/hcd.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'drivers') diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c index 5c51bf5506d1..2192a2873c7c 100644 --- a/drivers/usb/dwc2/hcd.c +++ b/drivers/usb/dwc2/hcd.c @@ -2480,8 +2480,10 @@ static void dwc2_free_dma_aligned_buffer(struct urb *urb) return; /* Restore urb->transfer_buffer from the end of the allocated area */ - memcpy(&stored_xfer_buffer, urb->transfer_buffer + - urb->transfer_buffer_length, sizeof(urb->transfer_buffer)); + memcpy(&stored_xfer_buffer, + PTR_ALIGN(urb->transfer_buffer + urb->transfer_buffer_length, + dma_get_cache_alignment()), + sizeof(urb->transfer_buffer)); if (usb_urb_dir_in(urb)) { if (usb_pipeisoc(urb->pipe)) @@ -2513,6 +2515,7 @@ static int dwc2_alloc_dma_aligned_buffer(struct urb *urb, gfp_t mem_flags) * DMA */ kmalloc_size = urb->transfer_buffer_length + + (dma_get_cache_alignment() - 1) + sizeof(urb->transfer_buffer); kmalloc_ptr = kmalloc(kmalloc_size, mem_flags); @@ -2523,7 +2526,8 @@ static int dwc2_alloc_dma_aligned_buffer(struct urb *urb, gfp_t mem_flags) * Position value of original urb->transfer_buffer pointer to the end * of allocation for later referencing */ - memcpy(kmalloc_ptr + urb->transfer_buffer_length, + memcpy(PTR_ALIGN(kmalloc_ptr + urb->transfer_buffer_length, + dma_get_cache_alignment()), &urb->transfer_buffer, sizeof(urb->transfer_buffer)); if (usb_urb_dir_out(urb)) -- cgit v1.2.3