> -----Original Message----- > From: Valentin Longchamp [mailto:valentin.longch...@keymile.com] > Sent: 30 March 2012 17:45 > To: Prafulla Wadaskar > Cc: u-boot@lists.denx.de; Gerlando Falauto; Holger Brunck > Subject: Re: [PATCH v2] spi/kirkwood: add weak functions > board_spi_bus_claim/release > > Hi Prafulla, > > For the simplicity of the discussion, I have removed everything in the > discussion that is not relevant for the current open point. > > On 03/30/2012 01:34 PM, Prafulla Wadaskar wrote: > > In Kirkwood specific claim_bus API, you will backup default > configuration (which is NF in your case) for these particular pins > (SPI_SI, SPI_SCK, SPI_CSn, MOSI, MISO). > > But which MPP are these particular pins ? > > Let's have a look at a single signal, SPI_SCK for instance. From the > 88F6281 > Hardware Spec [1], page 53, SPI_SCK can be MPP[2], MPP[10]. How can > the generic > driver know which one actually is wired to the SPI device SCK pin on > the > currently running hardware (when none is configured as then, since by > default > for us MPP[2] is NF_IO[4] and MPP[10] is UA0_TXD ) ? This is a board > specific ! > > If you tell me how I easily can find this out in the kirkwood driver,
Dear Valentin Please make a use of CONFIG_SF_DEFAULT_CS for this. By default this is defined to 0, lets map it to our default use case i.e. using MPP0-3 for default SPI signals One may pre-define this in his board config as per specific need, and we can use this effectively in Kirkwood_spi driver. i.e. bit0 to be used to configure SPI_CSn bit1 to be used to configure SPI_MOSI... and so on so if my needs are to use 1. MPP7 as SPI_CSn I will define CONFIG_SF_DEFAULT_CS to 0x01 2. MPP6 as SPI_MOSI I will define CONFIG_SF_DEFAULT_CS to 0x02 2. MPP6 as SPI_MOSI and MPP7 as SPI_CSn, I will define CONFIG_SF_DEFAULT_CS to 0x03 .. and so on. Regards.. Prafulla . . . > I will be > happy to implement your proposed solution. Otherwise, I think we > should stick > with the board specific function. > > [1] > http://www.marvell.com/embedded- > processors/kirkwood/assets/HW_88F6281_OpenSource.pdf > > Regards > > -- > Valentin Longchamp > Embedded Software Engineer > Hardware and Chip Integration > ______________________________________ > KEYMILE AG > Schwarzenburgstr. 73 > CH-3097 Liebefeld > Phone +41 31 377 1318 > Fax +41 31 377 1212 > valentin.longch...@keymile.com > www.keymile.com > ______________________________________ > KEYMILE: A Specialist as a Partner _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
