Using latest kernel, I noticed slow MMC access. Our board supports both eMMC and micro-SD-card memory.
On both memories, an ext4 fs is installed and mounted with default options. I measured write speeds of about 2MBytes/sec on both flash media.
According to the performance guide http://processors.wiki.ti.com/index.php/AM335x-PSP_04.06.00.07_Features_and_Performance_Guide roughly 8MB should be possible.
I merged also following patch: http://arago-project.org/git/projects/?p=linux-am33x.git;a=commit;h=36800bd1ae85fd459f348323c630fd173a18ba4b
In the board setup file I added following capability: MMC_CAP_4_BIT_DATA
Electrical signals are looking fine on a scope.
Kernel log:
[ 1.319458] mmc0: host does not support reading read-only switch. assuming write-enable.
[ 1.330474] mmc0: new high speed SDHC card at address 1234
[ 1.336700] mmcblk0: mmc0:1234 SA04G 3.63 GiB
[ 1.344299] mmcblk0: p1 p2 p3 p4
[ 1.427307] mmc1: new high speed MMC card at address 0001
[ 1.433410] usb 2-1: new high-speed USB device number 2 using musb-hdrc
[ 1.440612] mmcblk1: mmc1:0001 HYNIX 1.68 GiB
[ 1.445648] mmcblk1boot0: mmc1:0001 HYNIX partition 1 1.00 MiB
[ 1.451995] mmcblk1boot1: mmc1:0001 HYNIX partition 2 1.00 MiB
[ 1.460449] mmcblk1: p1 p2 p3 p4
[ 1.466766] mmcblk1boot1: unknown partition table
[ 1.473602] mmcblk1boot0: unknown partition table
Question:
Does anyone have a suggestion to improve (write) speed?
Best regards,
Wim
