On 26/03/2020 05:51, Jaehoon Chung wrote:
On 3/26/20 1:09 AM, Matthias Brugger wrote:
On 24/03/2020 23:58, Jaehoon Chung wrote:
Enable SDHCI_SDMA configuration.
Signed-off-by: Jaehoon Chung jh80.chung@samsung.com Reviewed-by: Peng Fan peng.fan@nxp.com Reviewed-by: Minkyu Kang mk7.kang@samsung.com
configs/rpi_4_32b_defconfig | 1 + 1 file changed, 1 insertion(+)
diff --git a/configs/rpi_4_32b_defconfig b/configs/rpi_4_32b_defconfig index 72cda5d949..7189914606 100644 --- a/configs/rpi_4_32b_defconfig +++ b/configs/rpi_4_32b_defconfig @@ -25,6 +25,7 @@ CONFIG_DFU_MMC=y CONFIG_DM_KEYBOARD=y CONFIG_DM_MMC=y CONFIG_MMC_SDHCI=y +CONFIG_MMC_SDHCI_SDMA=y
RPi4 can only do DMA transfers to the first GiB of memory. I wasn't sucessfull in understanding the mmc/sdhci code to see where we take the dma-ranges property into account so that we don't use an address > 1 GiB.
Sorry i don't understand clearly what you said.
I'll try to rephrase: How do we make sure that DMA uses only addresses the in the first GiB of RAM for it's transactions. That a limitation the RPi4 has.
Are we safe in this regard? If we are, then we can also enable this for rpi_4_defconfig and rpi_arm64_defconfig I think.
I checked rpi_arm64_defconfig history. it's unified config for RPi3/RPI4. As i know, RPi3 doesn't support SDMA mode. So i don't have a plan to apply rpi_arm64_defconfig. (If i understood wrong, let me know,plz.)
Yes, well we have two different device tree compatibles for them. We have to change the driver to make sure only sdhci of RPi4 does enable SDMA.
Regards, Matthias
I have tested SDMA mode With rpi_4_defconfig / rpi_4_32b_defconfig. Test Environment
- Target : RPI4 (1G/2G/4G) target
- config : rpi_4_defconfig / rpi_4_32b_defconfig
Read/write some files from Sd-card. Read/write performance is increased than before.
I will resend with rpi_4_defconfig, except rpi_arm64_defconfig.
Best Regards, Jaehoon Chung
Regards, Matthias
CONFIG_MMC_SDHCI_BCM2835=y CONFIG_DM_ETH=y CONFIG_BCMGENET=y