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b=AkGi/Cy8Sg47tYGjd+LU0M7wRFFsSC6/16uBtqx5/DN3a639wXVEwjjPmmpMtHCsE W+L+PTHU9hL56PtIgkX10UcEatu2NY5c0Pnz6IYcDMXc6LJ5M0avYFHZ2pGGw7a/Ie EhUn9pZ4q8sCnHKyFofWOby7b89/+7Vly2Bg0Sh1DRNE//f8NS7CNxcp07eMoWHcUH +QzHfDn9kOAZQ045UFbEmkgbKkdvdOX2z+WqIEjhlQKDKlhvVc1gbpqvuKU72fjOUr idLkDeK/lFgcm4Yy4motfESTY0+TyB+m0Sc0HI9kx64JIBEMgjtW7g/eIvbdinEmAY oNGIaMv0uTJ2g== X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200914_101742_185677_FD6159F4 X-CRM114-Status: GOOD ( 11.54 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Lorenzo Pieralisi , catalin.marinas@arm.com, Leon Romanovsky , Benjamin Herrenschmidt , Bjorn Helgaas , linux-pci@vger.kernel.org, will@kernel.org, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Sep 11, 2020 at 09:42:25PM +0000, Clint Sbisa wrote: > There's no DMA involved with this BAR-- the driver writes a portion of the > packet contents in addition to the descriptors, which generally increases the > number of TLPs if write-combine isn't used. Furthermore, this BAR is only used > for writes and never for reads. You use DPDK without DMA? How does receive work? > As Jason noted in the other reply to this email, the Linux ENA driver makes use > of WC by using devm_ioremap_wc(). As Ben noted we don't have kernel accessors to make this portable or safe :( Jason _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel