Using a SPI port on DM365

Please refer to the kernel documentation at

$DEVDIR/kernel/linux-2.6.32/Documentation/spi

Hi Todd,

Is the SPI initialized on startup or do I have to initialize myself? I can't find the spi0 device in /dev/spi0. If spi0 is not initialize how do you do it?

Thanks.

Regards.

Irwin Liew

Hi,

In order to use Spi0 you need to check the following files:

LeopardBoardDM365sdkEVAL2011Q2/bootloader/u-boot-2010.12-rc2-psp03.01.01.39/src/board/davinci/dm365leopard/dm365leopard.c and check for Pinmux values

Also

LeopardBoardDM365sdkEVAL2011Q2/bootloader/u-boot-2010.12-rc2-psp03.01.01.39/src/include/configs/davinci_dm365leopard.h and check for the SPI base

hi,Carlos

if i want to use Leopardboard J8,GIO22 -GIO25 ,say ,spi0_scs[0],spi0_sclk,spi0_somi,spi0_simo

as your post above,i must revise dm365leopard.c

original code

/* Enable SPI0 ports */

/* writel(((readl(PINMUX3) & 0x81FFFFFF) | 0x36000000), PINMUX3); */

/* REG(PINMUX3) |= 0x36000000; */

/* Enable SPI1 ports */

writel(((readl(PINMUX3) & 0x7FFFFFFF) | 0x80000000), PINMUX3);

writel(((readl(PINMUX4) & 0xFFFFFFC0) | 0x00000015), PINMUX4);

// REG(PINMUX3) |= 0x80000000;

// REG(PINMUX4) |= 0x00000015;

revised to

/* Enable SPI0 ports */

writel(((readl(PINMUX3) & 0x81FFFFFF) | 0x36000000), PINMUX3);

REG(PINMUX3) |= 0x36000000;

/* Enable SPI1 ports */

writel(((readl(PINMUX3) & 0x7FFFFFFF) | 0x80000000), PINMUX3);

writel(((readl(PINMUX4) & 0xFFFFFFC0) | 0x00000015), PINMUX4);

// REG(PINMUX3) |= 0x80000000;

// REG(PINMUX4) |= 0x00000015;

and davinci_dm365leopard.h

#define CONFIG_SYS_SPI_BASE 0x01c66800

#define CONFIG_SYS_SPI0_BASE 0x01c66000

#define CONFIG_SYS_SPI1_BASE 0x01c66800

#define CONFIG_SYS_SPI2_BASE 0x01c67800

#define CONFIG_SYS_SPI3_BASE 0x01c68000

#define CONFIG_SYS_SPI4_BASE 0x01c23000

needn't revise

Am i right?

Hi,

You need to remove the SPI1 from the code (or comment it)

/* Enable SPI0 ports */

/* writel(((readl(PINMUX3) & 0x81FFFFFF) | 0x36000000), PINMUX3); */

/* REG(PINMUX3) |= 0x36000000; */

/* Enable SPI1 ports */

writel(((readl(PINMUX3) & 0x7FFFFFFF) | 0x80000000), PINMUX3);

writel(((readl(PINMUX4) & 0xFFFFFFC0) | 0x00000015), PINMUX4);

// REG(PINMUX3) |= 0x80000000;

// REG(PINMUX4) |= 0x00000015;

revised to

/* Enable SPI0 ports */

writel(((readl(PINMUX3) & 0x81FFFFFF) | 0x36000000), PINMUX3);

//REG(PINMUX3) |= 0x36000000;

/* Enable SPI1 ports */

//writel(((readl(PINMUX3) & 0x7FFFFFFF) | 0x80000000), PINMUX3);

//writel(((readl(PINMUX4) & 0xFFFFFFC0) | 0x00000015), PINMUX4);

// REG(PINMUX3) |= 0x80000000;

// REG(PINMUX4) |= 0x00000015;

Davinci_dm365leopard.h doesn't need to be changed

As Todd said, documentation can help a lot, a good guide of the dm365 registers can be found at TI's website:

http://focus.ti.com/dsp/docs/dspsupporttechdocs.tsp?sectionId=3&tabId=409&viewType=mostuseful&rootFamilyId=44&familyId=1446&docCategoryId=6

Look for the DM365 ARM subsystem

hi,carlos

why do you revise u-boot code,that is LeopardBoardDM365sdkEVAL2011Q2/bootloader/u-boot-2010.12-rc2-psp03.01.01.39/src/board/davinci/dm365leopard/dm365leopard.c ,and not kernel/linux-2.6.32.17-psp03.01.01.39/arch/arm/mach-davinci/board-dm365-leopard.c

i think you should revise kernel,not uboot.

why?any comment?thank u.

hi,

That depends on your needs, SPI at uboot can be used to configure some device (that can be done at kernel too). If you dont initialize pinmux SPI registers at uboot you will need to do it at the board-dm365-leopard.c

If you want to use SPI at kernel there's documentation about SPI and kernel at:

$DEVDIR/kernel/linux-2.6.32/Documentation/spi