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Request to add scimmc driver to dreamshell - Версия для печати

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+--- Тема: Request to add scimmc driver to dreamshell (/thread-2329.html)



Request to add scimmc driver to dreamshell - cyrusmaintea - 05.10.2015 05:17

So i stubled across this on the netbsd mailing lists.
NetBSD Mailing List
And i decided to build this into my dreamcast. i have a thread over on assembler
My build

And i was wondering if a driver could be incorporated into the next dreamshell.

the exposed bus is the same one between the SH4 and PVR and the netbsd driver looks to be down clocked to 500 or so khz with a division of 1000 in the driver i messed with.

doesn't this bus scale to ~800Mhz?


RE: Request to add scimmc driver to dreamshell - SWAT - 05.10.2015 09:47

It has long been thought to add SPI driver on internal SCI (looks like it's can be drive native SPI protocol without bit-bang), but the feasibility of this is questionable, since there is much more productive mod - G1-ATA.
For your mod need open console box and solder wires, so maybe best way do G1-ATA instead? Current SPI mod is good because it can be used without modification of the console, so I'll keep it forever.
If you can solder wires - why not do G1-ATA, it's best choice. But just for fun I can do SPI for SCI, why not Smile
Low speed (~500kHz) need only for initialization of SD, after init, it's may increased to max speed. But I'm not sure what is the max speed, need test.


RE: Request to add scimmc driver to dreamshell - cyrusmaintea - 05.10.2015 16:30

im sure that 800mhz i posted in OP was from my lack of sleep XD, it should not exceed 150mhz i think. and swat i was thinking this could be neat to mess around with, if got to work with dma on netbsd it would be much faster.

or if i could get some sources for the g1ata driver, i could try to port it into the grdom driver in netbsd


RE: Request to add scimmc driver to dreamshell - SWAT - 05.10.2015 19:51

And 150 MHz is too much, SPI in modern devices can give max 25-50 MHz in general. it's very fast. I think on DC we can get max 3 MHz.
You can get source code from KallistiOS - http://sourceforge.net/p/cadcdev/kallistios/ci/master/tree/kernel/arch/dreamcast/hardware/g1ata.c


RE: Request to add scimmc driver to dreamshell - cyrusmaintea - 06.10.2015 01:06

ok thanks ^^, ye over 50mhz is problematic.


RE: Request to add scimmc driver to dreamshell - SWAT - 06.10.2015 08:29

Can you show me source code of SCI SPI driver?


RE: Request to add scimmc driver to dreamshell - cyrusmaintea - 06.10.2015 17:07

https://www.dropbox.com/s/63p26fdxh84me8n/sdmmc.zip?dl=0

thats the dir under the netbsd buildroot. contains original diff patch and the patched files.
scimci.c is one too look at first.


RE: Request to add scimmc driver to dreamshell - cyrusmaintea - 06.10.2015 19:11

Sry for double posting this.
https://www.dropbox.com/s/6mxdi67cnd5sc7y/libg1ata.zip?dl=0
i made a semi-portable libg1ata, and i wanted to start messin with adding support for external optical devices
such as a std dvd rom drive. thats rlly why i made the g1ata lib as posted; so i can get an idea of how im guna make this all work
while hopefully making a contribution lol

fixed my issue lol

[Изображение: TOhLhoE.png]

wip ^ new log pic


RE: Request to add scimmc driver to dreamshell - SWAT - 07.10.2015 09:14

(06.10.2015 17:07)cyrusmaintea писал(а):  https://www.dropbox.com/s/63p26fdxh84me8n/sdmmc.zip?dl=0

thats the dir under the netbsd buildroot. contains original diff patch and the patched files.
scimci.c is one too look at first.

Yeah, SCI can drive SPI by native hardware.
I assumed this by docs for the CPU, but it's practical confirmation!
And can use DMA for data transfer and this very good.
But 500 KHz it's too slow Sad Maybe can be increased? Need tests.


RE: Request to add scimmc driver to dreamshell - cyrusmaintea - 07.10.2015 12:08

Update: heres some kernels
https://www.dropbox.com/s/75kqq8kb6..._MMC-NetBSD-6.0-scif0-pvr0-multipack.rar?dl=0

oh btw swat those kernels are clocked with ***(2500 * 1000), so the bus turns out to be 3.114 MHz 8bit width. its soooo much faster vs 519Khz lol


RE: Request to add scimmc driver to dreamshell - cyrusmaintea - 09.10.2015 18:25

https://www.dropbox.com/s/uyxz6j4bxz9n4sq/Kallistios-2.0-WebDoc-Offline.zip?dl=0

I bundled the kallistios 2.0 webdocs and uploaded it for people to download and view the documentation of kallistios 2.0 offline for convenience.
cheers ^^


RE: Request to add scimmc driver to dreamshell - SWAT - 11.10.2015 08:28

Can you make speed test on filesystem?


RE: Request to add scimmc driver to dreamshell - cyrusmaintea - 12.10.2015 18:43

i actually am stuck for now till i can get ahold of my replacement dreamcast from a friend across state. i fried the sh4 cpu doing a 2.4v overvolt + 54Mhz clock signal mod, i got around 324mhz sh4 and it was way over the top, within 10 minutes the poor little guys heart died.


RE: Request to add scimmc driver to dreamshell - SWAT - 12.10.2015 19:42

Extremal overclock needs very good cooling...


RE: Request to add scimmc driver to dreamshell - cyrusmaintea - 06.02.2016 21:34

Finally Finished my replacement dreamcast swat. Did you manage to start porting the sci driver to ds? i recently finished my new NetBSD build and just need to test the build now. today ima make the sdcard w/ rootfs again and hope it works lol. I might have to go back to the motherboard and triple check the scimmc mod i put into the new dc is wired correctly.

other then that here is the download.

https://www.dropbox.com/s/2fem398kk40qqx5/DC_NetBSD_7_RC3_SCIMMC_Serial_Console.zip?dl=0

ill report a speed log asap.


RE: Request to add scimmc driver to dreamshell - SWAT - 07.02.2016 10:42

I downloaded. But as long as I do not have free time to do it. I therefore issued a release ahead of time for this reason. It's not really finished.
I need this mod for check the driver, so it's not fast. BTW you can add driver himself.


RE: Request to add scimmc driver to dreamshell - cyrusmaintea - 10.02.2016 02:53

(07.02.2016 10:42)SWAT писал(а):  I downloaded. But as long as I do not have free time to do it. I therefore issued a release ahead of time for this reason. It's not really finished.
I need this mod for check the driver, so it's not fast. BTW you can add driver himself.

how would i go about adding the driver to ds? is it included in RC4 src?
or manually implement?


RE: Request to add scimmc driver to dreamshell - SWAT - 10.02.2016 20:04

Need implement, DS doesn't included this driver.