From mboxrd@z Thu Jan 1 00:00:00 1970 From: tomasz.figa@gmail.com (Tomasz Figa) Date: Wed, 19 Jun 2013 20:23:19 +0200 Subject: [RFC PATCH 11/11] ARM: s3c64xx: Add support for DMA using generic amba-pl08x driver In-Reply-To: References: <1371416058-22047-1-git-send-email-tomasz.figa@gmail.com> <1371416058-22047-12-git-send-email-tomasz.figa@gmail.com> Message-ID: <91444857.CpeBVZzDHZ@flatron> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Monday 17 of June 2013 16:04:47 Linus Walleij wrote: > On Sun, Jun 16, 2013 at 10:54 PM, Tomasz Figa wrote: > > This patch adds all required platform-specific data and initialization > > code to support the generic amba-pl08x driver on S3C64xx SoCs. > > > > Also some compatibility definitions are added to make the transition > > from legacy API to DMA engine easier. The biggest hack here is > > passing const char * pointers through DMA resource, casted to > > unsigned long, but this is how Samsung DMA wrappers (used to support > > both s3c-dma and DMA engine in drivers) is designed. > > > > Signed-off-by: Tomasz Figa > > Patch looks like an OK stepping stone. > > > +static AMBA_AHB_DEVICE(s3c64xx_dma0, "dma-pl080s.0", 0x0a141080, > > + 0x75000000, {IRQ_DMA0}, > > &s3c64xx_dma0_plat_data); > (...) > > > +static AMBA_AHB_DEVICE(s3c64xx_dma1, "dma-pl080s.1", 0x0a141080, > > + 0x75100000, {IRQ_DMA1}, > > &s3c64xx_dma1_plat_data); > Ah, does this mean the device does not have any AMBA PrimeCell ID > contents? Hmm, not really. The ID here is what I copied from PrimeCell ID registers and the method of registration is taken from S5PV210. If I remove the override, it will read the same value from registers. > Then use the ID 0x00053080 instead of 0x0a141080 > > 0x53 is "S" for Samsung. Variant 0. Well, that's kind of solution to make sure that it won't conflict with any future variant manufactured by ARM, I guess. Best regards, Tomasz