U-boot SPI/MMC new api

Altera_Forum · ‎08-16-2010

I'm trying to get MMC working with version 2010.06 of U-Boot.

There were several problems. The first one is that the structure of the directories is different. At http://www.nioswiki.com/dasuboot/u-boot_and_cyclone_ii-de2_boards explains that file mmc_spi.c must be copied to cpu/nios2. This is changed the last version to U-Boot u-boot\arch\nios2\cpu

I changed in the Makefile:


COBJS    = cpu.o interrupts.o sysid.o traps.o epcs.o

to


COBJS    = cpu.o interrupts.o sysid.o traps.o epcs.o mmc_spi.o

The second problem was that the file mmc.h must be copie to include/asm-nios2/arch-nios2/ according the wiki. This is changed in the last version of U-Boot to u-boot\arch\nios2\include\asm

Because of this I had to change the include files in the mmc_spi.c from:

# include <common.h># include <nios2-io.h># include <asm/io.h># include <mmc.h>

to

# include <common.h># include <nios2-io.h># include <asm/io.h># include <asm/mmc.h>

The API of MMC in u-boot changed as well and therefor I had to change the function:


int mmc_read(ulong addr, uchar *buff,int size)

into:


int mmc_read(struct mmc *mmc, u64 src, uchar *dst, int size)

The function:


int mmc_init(int verbose)

changed into:


int mmc_legacy_init(int verbose)

At this point the code compiled with no warning! But the driver crached with no error when I called "mmc init mmc0"

After some research I found out that the problem was still in the mmc.h file. The marco (for example):

# define SPI_TXDATA(val)        writel( MMC_SPI_BASE + 4, (val))

is calling writel. The parameters to call this functions changed!!

Orgineel (read old U-Boot):

# define writel(addr,val)
       asm volatile ("stwio %1, 0(%0)" : : "r" (addr), "r" (val))

New (read current u-boot):

# define writel(val,addr)
       asm volatile ("stwio %0, 0(%1)" : : "r" (val), "r" (addr))
/
Therefor a changed all the marcos with (addr) and (val) swapped (for example):
# define SPI_TXDATA(val)        writel( MMC_SPI_BASE + 4, (val))

changed to:

# define SPI_TXDATA(val)        writel((val), MMC_SPI_BASE + 4)

I recompiled U-boot, the driver is not crashing anymore when I called "mmc init mmc0", but the output is:

No MMC card found

The function mmc_legacy_init is return -1. I located the problem at:


    send_cmd(cmd0); /* GO_IDLE_STATE */
    if (rcv_response(0, rsp, 0))
  {
    return -1;
  }

At this piont I don't know how to get MMC to work. Has someone an idea?

Altera_Forum · ‎08-23-2010

I have rewritten my first (initial) post!