From e8f8c14d9da7ab1b8a7b0f769cd7148ca2cc7d10 Mon Sep 17 00:00:00 2001 From: Paul Zimmerman <Paul.Zimmerman@synopsys.com> Date: Tue, 16 Sep 2014 13:47:26 -0700 Subject: [PATCH] usb: dwc2: clip max_transfer_size to 65535 Clip max_transfer_size to 65535 for host. dwc2_hc_setup_align_buf() allocates coherent buffers with this size, and if it's too large we can exhaust the coherent DMA pool. Tested on Raspberry Pi and Altera SOCFPGA. Signed-off-by: Paul Zimmerman <paulz@synopsys.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- drivers/usb/dwc2/core.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/usb/dwc2/core.c b/drivers/usb/dwc2/core.c index ea0048a724cff..d9269459d481e 100644 --- a/drivers/usb/dwc2/core.c +++ b/drivers/usb/dwc2/core.c @@ -2743,6 +2743,13 @@ int dwc2_get_hwparams(struct dwc2_hsotg *hsotg) width = (hwcfg3 & GHWCFG3_XFER_SIZE_CNTR_WIDTH_MASK) >> GHWCFG3_XFER_SIZE_CNTR_WIDTH_SHIFT; hw->max_transfer_size = (1 << (width + 11)) - 1; + /* + * Clip max_transfer_size to 65535. dwc2_hc_setup_align_buf() allocates + * coherent buffers with this size, and if it's too large we can + * exhaust the coherent DMA pool. + */ + if (hw->max_transfer_size > 65535) + hw->max_transfer_size = 65535; width = (hwcfg3 & GHWCFG3_PACKET_SIZE_CNTR_WIDTH_MASK) >> GHWCFG3_PACKET_SIZE_CNTR_WIDTH_SHIFT; hw->max_packet_count = (1 << (width + 4)) - 1; -- GitLab