[U-Boot] [PATCH V3 4/9] EXYNOS5: DWMMC: Added FDT support for DWMMC

Jaehoon Chung jh80.chung at samsung.com
Thu Jan 3 07:48:48 CET 2013


Hi Amar,

..snip..
>>>  }
>>>
>>>  int exynos_dwmci_init(u32 regbase, int bus_width, int index)
>>>  {
>>>       struct dwmci_host *host = NULL;
>>> +     int dev_id = 0;
>>>       host = malloc(sizeof(struct dwmci_host));
>>>       if (!host) {
>>>               printf("dwmci_host malloc fail!\n");
>>>               return 1;
>>>       }
>>> +     /* Convert index into corresponding peripheral ID */
>>> +     dev_id = index + PERIPH_ID_SDMMC0;
>> Is it right at every case?
>>
> 
> Yes, it is right in every case.
> 
> Consider the finction "int exynos_dwmci_init(u32 regbase, int bus_width,
> int index)"
> If the input argument 'index' is between (0-3), then the statement "dev_id
> = index + PERIPH_ID_SDMMC0;" works good.
> 
> So, the function exynos_dwmci_init(u32 regbase, int bus_width, int index)
> is being called as below
> 1) FDT Case:
> The function exynos_dwmmc_init() calls exynos_dwmmc_init()
> The dev_id is extracted from arch/arm/dts/exynos5250.dtsi. The dev_id is
> nothing but the interrupt number.
> dwmmc0 - dev_id = 75
> dwmmc1 - dev_id = 76
> dwmmc2 - dev_id = 77
> dwmmc3 - dev_id = 78
> 
> At same time the enum values are (Refer
> "arch/arm/include/asm/arch-exynos/periph.h")
> PERIPH_ID_SDMMC0 = 75,
> PERIPH_ID_SDMMC1,
> PERIPH_ID_SDMMC2,
> PERIPH_ID_SDMMC3,
> 
>  Here "index = dev_id - PERIPH_ID_SDMMC0" works good for all channels
> (mmc0 - mmc3)
> 
> As proper values are mentioned in arch/arm/dts/exynos5250.dtsi, proper
> values of "index" (i.e 0 - 3) will be computed here.
> 
> 2) Non-FDT case:
> The function board_mmc_init() calls exynos_dwmmc_init() as shown below
> int board_mmc_init(bd_t *bis)
> {
>  ....
>  ....
>         /*EMMC: dwmmc Channel-0 with 8 bit bus width */
>         err = exynos_dwmmc_init(0, 8);
> }
> Here the coder shall ensure to pass proper index number (0 to 3) for porper
> working.

Sorry, i confused the dev_id and dev_index..Thank you for explanation.

Best Regards,
Jaehoon Chung
> 
> 
>>  > +
>>> +     /* set the clock divisor - clk_div_fsys for mmc */
>>> +     if (exynos5_mmc_set_clk_div(dev_id)) {
>>> +             debug("mmc clock div set failed\n");
>>> +             return -1;
>>> +     }
>>>
>>>       host->name = EXYNOS_NAME;
>>>       host->ioaddr = (void *)regbase;
>>>       host->buswidth = bus_width;
>>> +#ifdef CONFIG_OF_CONTROL
>>> +     host->clksel_val = (DWMCI_SET_SAMPLE_CLK(timing[0]) |
>>> +                             DWMCI_SET_DRV_CLK(timing[1]) |
>>> +                             DWMCI_SET_DIV_RATIO(timing[2]));
>>> +#else
>>> +     if (0 == index)
>>> +             host->clksel_val = DWMMC_MMC0_CLKSEL_VAL;
>>> +     if (2 == index)
>>> +             host->clksel_val = DWMMC_MMC2_CLKSEL_VAL;
>>> +#endif
>>>       host->clksel = exynos_dwmci_clksel;
>>>       host->dev_index = index;
>>> -
>>> -     add_dwmci(host, 52000000, 400000);
>>> +     host->mmc_clk = exynos_dwmci_get_clk;
>>> +     /* Add the mmc chennel to be registered with mmc core */
>>> +     add_dwmci(host, DWMMC_MAX_FREQ, DWMMC_MIN_FREQ);
>>>
>>>       return 0;
>>>  }
>>>
>>> +#ifdef CONFIG_OF_CONTROL
>>> +unsigned int exynos_dwmmc_init(const void *blob)
>>> +{
>>> +     u32 base;
>>> +     int index, bus_width;
>>> +     int node_list[DWMMC_MAX_CH_NUM];
>>> +     int err = 0;
>>> +     int dev_id, flag;
>>> +     int count, i;
>>> +
>>> +     count = fdtdec_find_aliases_for_id(blob, "dwmmc",
>>> +                             COMPAT_SAMSUNG_EXYNOS5_DWMMC, node_list,
>>> +                             DWMMC_MAX_CH_NUM);
>>> +
>>> +     for (i = 0; i < count; i++) {
>>> +             int node = node_list[i];
>>> +
>>> +             if (node <= 0)
>>> +                     continue;
>>> +
>>> +             /* Extract device id for each mmc channel */
>>> +             dev_id = pinmux_decode_periph_id(blob, node);
>>> +
>>> +             /* Get the bus width from the device node */
>>> +             bus_width = fdtdec_get_int(blob, node,
>> "samsung,bus-width", 0);
>>> +             if (bus_width < 0) {
>>> +                     debug("DWMMC: Can't get bus-width\n");
>>> +                     return -1;
>>> +             }
>>> +             if (8 == bus_width)
>>> +                     flag = PINMUX_FLAG_8BIT_MODE;
>>> +             else
>>> +                     flag = PINMUX_FLAG_NONE;
>>> +
>>> +             /* config pinmux for each mmc channel */
>>> +             err = exynos_pinmux_config(dev_id, flag);
>>> +             if (err) {
>>> +                     debug("DWMMC not configured\n");
>>> +                     return err;
>>> +             }
>>> +
>>> +             index = dev_id - PERIPH_ID_SDMMC0;
>>> +
>>> +             /* Get the base address from the device node */
>>> +             base = fdtdec_get_addr(blob, node, "reg");
>>> +             if (!base) {
>>> +                     debug("DWMMC: Can't get base address\n");
>>> +                     return -1;
>>> +             }
>>> +             /* Extract the timing info from the node */
>>> +             err = fdtdec_get_int_array(blob, node, "samsung,timing",
>>> +                                     timing, 3);
>>> +             if (err) {
>>> +                     debug("Can't get sdr-timings for divider\n");
>>> +                     return -1;
>>> +             }
>>> +             /* Initialise each mmc channel */
>>> +             err =  exynos_dwmci_init(base, bus_width, index);
>>> +             if (err) {
>>> +                     debug("Can't do dwmci init\n");
>>> +                     return -1;
>>> +             }
>>> +     }
>>> +
>>> +     return 0;
>>> +}
>>> +#endif
>>> diff --git a/include/dwmmc.h b/include/dwmmc.h
>>> index c8b1d40..4a42849 100644
>>> --- a/include/dwmmc.h
>>> +++ b/include/dwmmc.h
>>> @@ -123,6 +123,9 @@
>>>  #define MSIZE(x)             ((x) << 28)
>>>  #define RX_WMARK(x)          ((x) << 16)
>>>  #define TX_WMARK(x)          (x)
>>> +#define RX_WMARK_SHIFT               16
>>> +#define RX_WMARK_MASK                (0xfff << RX_WMARK_SHIFT)
>>> +
>>>
>>>  #define DWMCI_IDMAC_OWN              (1 << 31)
>>>  #define DWMCI_IDMAC_CH               (1 << 4)
>>> @@ -144,6 +147,7 @@ struct dwmci_host {
>>>       unsigned int bus_hz;
>>>       int dev_index;
>>>       int buswidth;
>>> +     u32 clksel_val;
>>>       u32 fifoth_val;
>>>       struct mmc *mmc;
>>>
>>>
>>
>>  _______________________________________________
>> U-Boot mailing list
>> U-Boot at lists.denx.de
>> http://lists.denx.de/mailman/listinfo/u-boot
>>
> 
> 
> 
> _______________________________________________
> U-Boot mailing list
> U-Boot at lists.denx.de
> http://lists.denx.de/mailman/listinfo/u-boot
> 



More information about the U-Boot mailing list