From mboxrd@z Thu Jan 1 00:00:00 1970 From: Adrian Hunter Subject: Re: [PATCH V10 3/4] mmc: sdhci: Add ADMA3 DMA support for V4 enabled host Date: Wed, 23 Jan 2019 09:27:38 +0200 Message-ID: <459c7d2e-38a6-cfe1-f3d0-a6ecdc2de0a9@intel.com> References: <1548186993-6229-1-git-send-email-skomatineni@nvidia.com> <1548186993-6229-3-git-send-email-skomatineni@nvidia.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1548186993-6229-3-git-send-email-skomatineni@nvidia.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Sowjanya Komatineni , robh+dt@kernel.org, mark.rutland@arm.com, mperttunen@nvidia.com, chunyan.zhang@unisoc.com, thierry.reding@gmail.com, jonathanh@nvidia.com, ulf.hansson@linaro.org Cc: anrao@nvidia.com, devicetree@vger.kernel.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mmc@vger.kernel.org List-Id: devicetree@vger.kernel.org On 22/01/19 9:56 PM, Sowjanya Komatineni wrote: > Below are the supported DMA types in Host Control1 Register > with Version 4 enable > b'00 - SDMA > b'01 - Not Used > b'10 - ADMA2 > b'11 - ADMA2 or ADMA3 > > ADMA3 uses Command Descriptor to issue an SD command. > A multi-block data transfer is performed by using a pair of CMD > descriptor and ADMA2 descriptor. > > ADMA3 performs multiple of multi-block data transfer by using > Integrated Descriptor which is more suitable for Command Queuing > to fetch both Command and Transfer descriptors. > > Host Capabilities register indiactes the supports of ADMA3 DMA. indiactes -> indicates > > Signed-off-by: Sowjanya Komatineni Acked-by: Adrian Hunter > --- > [V10]: Changes are same as V9 except this series has SDHCI core changes > into seperate patch > > drivers/mmc/host/sdhci.c | 9 ++++++++- > drivers/mmc/host/sdhci.h | 2 ++ > 2 files changed, 10 insertions(+), 1 deletion(-) > > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c > index a22e11a65658..c6afe793399e 100644 > --- a/drivers/mmc/host/sdhci.c > +++ b/drivers/mmc/host/sdhci.c > @@ -3353,7 +3353,14 @@ void sdhci_cqe_enable(struct mmc_host *mmc) > > ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL); > ctrl &= ~SDHCI_CTRL_DMA_MASK; > - if (host->flags & SDHCI_USE_64_BIT_DMA) > + /* > + * Host from V4.10 supports ADMA3 DMA type. > + * ADMA3 performs integrated descriptor which is more suitable > + * for cmd queuing to fetch both command and transfer descriptors. > + */ > + if (host->v4_mode && (host->caps1 & SDHCI_CAN_DO_ADMA3)) > + ctrl |= SDHCI_CTRL_ADMA3; > + else if (host->flags & SDHCI_USE_64_BIT_DMA) > ctrl |= SDHCI_CTRL_ADMA64; > else > ctrl |= SDHCI_CTRL_ADMA32; > diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h > index 6cc9a3c2ac66..4070be49d947 100644 > --- a/drivers/mmc/host/sdhci.h > +++ b/drivers/mmc/host/sdhci.h > @@ -88,6 +88,7 @@ > #define SDHCI_CTRL_ADMA1 0x08 > #define SDHCI_CTRL_ADMA32 0x10 > #define SDHCI_CTRL_ADMA64 0x18 > +#define SDHCI_CTRL_ADMA3 0x18 > #define SDHCI_CTRL_8BITBUS 0x20 > #define SDHCI_CTRL_CDTEST_INS 0x40 > #define SDHCI_CTRL_CDTEST_EN 0x80 > @@ -230,6 +231,7 @@ > #define SDHCI_RETUNING_MODE_SHIFT 14 > #define SDHCI_CLOCK_MUL_MASK 0x00FF0000 > #define SDHCI_CLOCK_MUL_SHIFT 16 > +#define SDHCI_CAN_DO_ADMA3 0x08000000 > #define SDHCI_SUPPORT_HS400 0x80000000 /* Non-standard */ > > #define SDHCI_CAPABILITIES_1 0x44 >