On Tue, May 14, 2013 at 3:51 PM, Heiko Stübner <heiko@xxxxxxxxx> wrote: > Am Dienstag, 14. Mai 2013, 14:47:19 schrieb Linus Walleij: >> On Sat, May 11, 2013 at 1:31 PM, Heiko Stübner <heiko@xxxxxxxxx> wrote: >> > Conceptually the s3c24xx-dma feels like a distant relative of the pl08x >> > with numerous virtual channels being mapped to a lot less physical ones. >> > The driver therefore borrows a lot from the amba-pl08x driver in this >> > regard. Functionality-wise the driver gains a memcpy ability in addition >> > to the slave_sg one. >> > >> > The driver currently only supports the "newer" SoCs which can use any >> > physical channel for any dma slave. Support for the older SoCs where >> > each channel only supports a subset of possible dma slaves will have to >> > be added later. >> > >> > Tested on a s3c2416-based board, memcpy using the dmatest module and >> > slave_sg partially using the spi-s3c64xx driver. >> > >> > Signed-off-by: Heiko Stuebner <heiko@xxxxxxxxx> >> >> So have I understood correctly if I assume that *some* S3C >> variants, i.e. this: arch/arm/mach-s3c64xx/dma.c >> have a vanilla, unmodified, or just slightly modified >> PL08x block, while this DMAC is something probably based on >> the PL08x where some ASIC engineer has had a good time hacking >> around in the VHDL code to meet some feature requirements. >> Correct? Or plausible guess? > > You're guess is at good as mine :-) . The public s3c64xx (ARM11 based) > documentation says that it is using s PL080 as dma controller while the > s3c24xx (ARM9 based) SoCs have this one, which doesn't come with any label in > the manuals. > Similar to the s3c64xx using a vic, while the s3c24xx uses something > homegrown. > > The relationship description was more based on the concepts used, i.e. the > virtual channel concept and general handling of dma transfers feel somehow > similar - as I said these are my first steps into this, so I still need to > understand a lot. OK then, a separate driver seems required, will look a bit closer at the patch as such. Yours, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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