[U-Boot] [PATCH v2 1/3] mmc: Read sd card detect properties from DT

Marek Vasut marek.vasut at gmail.com
Sat Jun 22 20:01:17 UTC 2019


On 6/22/19 8:58 PM, Suniel Mahesh wrote:
> Hi Marek,

Hi,

> Looks like CD is working fine with TI AM3358X SOC based targets.

Yes, it does.

> Ran a quick test after looking at the discussion, posting the results which might be of some help.

I think you misunderstood my proposal.

mmc rescan ; mmc part ; <replace card> ; mmc rescan ; mmc part obviously
works, because of the second mmc rescan. Try without the second mmc
rescan, you'll get the old results.

My proposal was suggesting that we add the ability to poll CD into the
u-boot main loop and detect the card replacement in the background, thus
making "mmc rescan" basically a no-op. Then, if the user replaced the
card, the user won't have to worry about running "mmc rescan" or
forgetting to do so.

> In this test, mmc part is not printing the partition table of the previous card, instead it prints
> the partition table of the latest card which is inserted.
> 
> Hope the test is inline with the discussion. Please ignore if the results doesn't make any sense.
> 
> Tested on U-Boot v2019.07-rc1
> 
> 8GB card inserted
> 
> => mmc rescan
> => mmc part
> 
> Partition Map for MMC device 0  --   Partition Type: DOS
> 
> Part    Start Sector    Num Sectors     UUID            Type
>   1     2048            262144          7d8cd224-01     0b Boot
>   2     264192          15259648        7d8cd224-02     83
> 
> => mmc info
> Device: OMAP SD/MMC
> Manufacturer ID: 3
> OEM: 5344
> Name: SS08G 
> Bus Speed: 48000000
> Mode : SD High Speed (50MHz)
> Rd Block Len: 512
> SD version 3.0
> High Capacity: Yes
> Capacity: 7.4 GiB
> Bus Width: 4-bit
> Erase Group Size: 512 Bytes
> 
> 
> removed 8GB card and inserted 2GB card
> 
> => mmc rescan
> => mmc part
> 
> Partition Map for MMC device 0  --   Partition Type: DOS
> 
> Part    Start Sector    Num Sectors     UUID            Type
>   1     2048            262144          000c0116-01     0b Boot
>   2     264192          3647488         000c0116-02     83
> => mmc info  
> Device: OMAP SD/MMC
> Manufacturer ID: 1b
> OEM: 534d
> Name: 00000 
> Bus Speed: 48000000
> Mode : SD High Speed (50MHz)
> Rd Block Len: 512
> SD version 3.0
> High Capacity: No
> Capacity: 1.9 GiB
> Bus Width: 4-bit
> Erase Group Size: 512 Bytes
> 
> Thanks
> 
> Regards
> 


-- 
Best regards,
Marek Vasut


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