[U-Boot] [U-boot] mmc write|read howto
Hi All,
I need some help regarding mmc write and mmc read commands usage.
I am using a 4GB SD/MMC plus and socked eMMC cards, usually I am formatting these cards on my host pc with fat partition and copy the images into card. while in the u-boot level I am reading the images from card and copy it onto mem addr like fatload mmc 0 0x1000 uImage.
Can we write the images onto these cards in u-boot level?, using mmc write. same way can we read back using mmc read? if so how to do that.
Request for help.
Thanks, Jagan.
Hi, Jagan
On 4/27/2013 4:51 AM, Jagan Teki wrote:
Hi All,
I need some help regarding mmc write and mmc read commands usage.
I am using a 4GB SD/MMC plus and socked eMMC cards, usually I am formatting these cards on my host pc with fat partition and copy the images into card. while in the u-boot level I am reading the images from card and copy it onto mem addr like fatload mmc 0 0x1000 uImage.
Can we write the images onto these cards in u-boot level?, using mmc write. same way can we read back using mmc read? if so how to do that.
yes, define the CONFIG_FAT_WRITE macro in your board config file. re-build your u-boot. then you will find "fatwrite" command.
U-Boot> fatwrite fatwrite - write file into a dos filesystem
Usage: fatwrite <interface> <dev[:part]> <addr> <filename> <bytes> - write file 'filename' from the address 'addr' in RAM to 'dev' on 'interface'
so you can use: fatwrite mmc 0 0x20000000 file 0x4000
Best Regards, Josh Wu
Request for help.
Thanks, Jagan. _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
Hi Josh,
On Sat, Apr 27, 2013 at 11:55 AM, Josh Wu josh.wu@atmel.com wrote:
Hi, Jagan
On 4/27/2013 4:51 AM, Jagan Teki wrote:
Hi All,
I need some help regarding mmc write and mmc read commands usage.
I am using a 4GB SD/MMC plus and socked eMMC cards, usually I am formatting these cards on my host pc with fat partition and copy the images into card. while in the u-boot level I am reading the images from card and copy it onto mem addr like fatload mmc 0 0x1000 uImage.
Can we write the images onto these cards in u-boot level?, using mmc write. same way can we read back using mmc read? if so how to do that.
yes, define the CONFIG_FAT_WRITE macro in your board config file. re-build your u-boot. then you will find "fatwrite" command.
U-Boot> fatwrite fatwrite - write file into a dos filesystem
Usage: fatwrite <interface> <dev[:part]> <addr> <filename> <bytes> - write file 'filename' from the address 'addr' in RAM to 'dev' on 'interface'
so you can use: fatwrite mmc 0 0x20000000 file 0x4000
Thanks for your information.
I will try the fatwrite, and this must require to have the card should formatted as FAT on host, is it? Any possibility to do the formation on u-boot itself.?
Thanks, Jagan.
Best Regards, Josh Wu
Request for help.
Thanks, Jagan. _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
On 4/27/2013 5:26 PM, Jagan Teki wrote:
Hi Josh,
On Sat, Apr 27, 2013 at 11:55 AM, Josh Wu josh.wu@atmel.com wrote:
Hi, Jagan
On 4/27/2013 4:51 AM, Jagan Teki wrote:
Hi All,
I need some help regarding mmc write and mmc read commands usage.
I am using a 4GB SD/MMC plus and socked eMMC cards, usually I am formatting these cards on my host pc with fat partition and copy the images into card. while in the u-boot level I am reading the images from card and copy it onto mem addr like fatload mmc 0 0x1000 uImage.
Can we write the images onto these cards in u-boot level?, using mmc write. same way can we read back using mmc read? if so how to do that.
yes, define the CONFIG_FAT_WRITE macro in your board config file. re-build your u-boot. then you will find "fatwrite" command.
U-Boot> fatwrite fatwrite - write file into a dos filesystem
Usage: fatwrite <interface> <dev[:part]> <addr> <filename> <bytes> - write file 'filename' from the address 'addr' in RAM to 'dev' on 'interface'
so you can use: fatwrite mmc 0 0x20000000 file 0x4000
Thanks for your information.
I will try the fatwrite, and this must require to have the card should formatted as FAT on host, is it?
yes. Also U-Boot can support EXT2, EXT4, UBI read. And EXT4 write (CONFIG_CMD_EXT4_WRITE).
Any possibility to do the formation on u-boot itself.?
according to my understanding, no.
Best Regards, Josh Wu
Thanks, Jagan.
Best Regards, Josh Wu
Request for help.
Thanks, Jagan. _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
Hi, Jagan
Since I am working on the fatwrite part for the moment. And there is a bug find in U-Boot fat write. You can check the thread here: http://article.gmane.org/gmane.comp.boot-loaders.u-boot/158939
following patch can fix it:
diff --git a/fs/fat/fat_write.c b/fs/fat/fat_write.c index 5829adf..b7ba8ea 100644 --- a/fs/fat/fat_write.c +++ b/fs/fat/fat_write.c @@ -561,7 +561,7 @@ set_cluster(fsdata *mydata, __u32 clustnum, __u8 *buffer, unsigned long size) { int idx = 0; - __u32 startsect; + __u32 startsect, nr_sectors;
if (clustnum > 0) startsect = mydata->data_begin + @@ -571,7 +571,11 @@ set_cluster(fsdata *mydata, __u32 clustnum, __u8 *buffer,
debug("clustnum: %d, startsect: %d\n", clustnum, startsect);
- if (disk_write(startsect, size / mydata->sect_size, buffer) < 0) { + nr_sectors = size / mydata->sect_size; + if (nr_sectors == 0) + nr_sectors = 1; + + if (disk_write(startsect, nr_sectors, buffer) < 0) { debug("Error writing data\n"); return -1; }
participants (2)
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Jagan Teki -
Josh Wu