From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dennis Dalessandro Subject: [PATCH 10/13] IB/hfi1: Adjust hardware buffering parameter Date: Sun, 25 Sep 2016 07:42:01 -0700 Message-ID: <20160925144159.10261.85155.stgit@scvm10.sc.intel.com> References: <20160925143656.10261.85231.stgit@scvm10.sc.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20160925143656.10261.85231.stgit-9QXIwq+3FY+1XWohqUldA0EOCMrvLtNR@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: dledford-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org Cc: Harish Chegondi , linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Dean Luick List-Id: linux-rdma@vger.kernel.org From: Harish Chegondi It was determined that 0x880 is a better value for hardware buffering, use it. Reviewed-by: Dean Luick Reviewed-by: Dennis Dalessandro Signed-off-by: Harish Chegondi Signed-off-by: Dennis Dalessandro --- drivers/infiniband/hw/hfi1/chip.c | 4 ++-- drivers/infiniband/hw/hfi1/chip.h | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/infiniband/hw/hfi1/chip.c b/drivers/infiniband/hw/hfi1/chip.c index 26c5ee5..88394cd 100644 --- a/drivers/infiniband/hw/hfi1/chip.c +++ b/drivers/infiniband/hw/hfi1/chip.c @@ -13385,9 +13385,9 @@ static void init_rbufs(struct hfi1_devdata *dd) /* * Give up after 1ms - maximum wait time. * - * RBuf size is 148KiB. Slowest possible is PCIe Gen1 x1 at + * RBuf size is 136KiB. Slowest possible is PCIe Gen1 x1 at * 250MB/s bandwidth. Lower rate to 66% for overhead to get: - * 148 KB / (66% * 250MB/s) = 920us + * 136 KB / (66% * 250MB/s) = 844us */ if (count++ > 500) { dd_dev_err(dd, diff --git a/drivers/infiniband/hw/hfi1/chip.h b/drivers/infiniband/hw/hfi1/chip.h index 92f2485..9234525 100644 --- a/drivers/infiniband/hw/hfi1/chip.h +++ b/drivers/infiniband/hw/hfi1/chip.h @@ -82,7 +82,7 @@ */ #define CM_VAU 3 /* HFI link credit count, AKA receive buffer depth (RBUF_DEPTH) */ -#define CM_GLOBAL_CREDITS 0x940 +#define CM_GLOBAL_CREDITS 0x880 /* Number of PKey entries in the HW */ #define MAX_PKEY_VALUES 16 -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html