[U-Boot] [PATCH V5 04/10] EXYNOS5: DWMMC: Added FDT support for DWMMC

Simon Glass sjg at chromium.org
Sat Jan 26 21:08:26 CET 2013


Hi,

On Tue, Jan 22, 2013 at 12:43 AM, Amar <amarendra.xt at samsung.com> wrote:
> This patch adds FDT support for DWMMC, by reading the DWMMC node data
> from the device tree and initialising DWMMC channels as per data
> obtained from the node.
>
> Signed-off-by: Vivek Gautam <gautam.vivek at samsung.com>
> Signed-off-by: Amar <amarendra.xt at samsung.com>

Acked-by: Simon Glass <sjg at chromium.org>

See below for nit/question.

> ---
> Changes since V1:
>         1)Updated code to have same signature for the function
>         exynos_dwmci_init() for both FDT and non-FDT versions.
>         2)Updated code to pass device_id parameter to the function
>         exynos5_mmc_set_clk_div() instead of index.
>         3)Updated code to decode the value of "samsung,width" from FDT.
>         4)Channel index is computed instead of getting from FDT.
>
> Changes since V2:
>         1)Updation of commit message and resubmition of proper patch set.
>
> Changes since V3:
>         1)Replaced the new function exynos5_mmc_set_clk_div() with the
>         existing function set_mmc_clk(). set_mmc_clk() will do the purpose.
>         2)Computation of FSYS block clock divisor (pre-ratio) is added.
>
> Changes since V4:
>         1)Replaced "unsigned int exynos_dwmmc_init(int index, int bus_width)" with
>         int exynos_dwmci_add_port(int, u32, inth, u32)
>                 i)exynos_dwmmc_add_port() will be used by non-FDT boards.
>                 ii)In FDT case, exynos_dwmmc_init(const void *blob) will use
>                 exynos_dwmmc_add_port() for every channel enabled in device node.
>         2)Changed the computation method of mmc clock divisor.
>         3)Updated exynos_dwmmc_init() to compute the 'clksel_val' within the function.
>
>  arch/arm/include/asm/arch-exynos/dwmmc.h |  11 +--
>  drivers/mmc/exynos_dw_mmc.c              | 127 ++++++++++++++++++++++++++++---
>  include/dwmmc.h                          |   3 +
>  3 files changed, 124 insertions(+), 17 deletions(-)
>
> diff --git a/arch/arm/include/asm/arch-exynos/dwmmc.h b/arch/arm/include/asm/arch-exynos/dwmmc.h
> index 8acdf9b..3b147b8 100644
> --- a/arch/arm/include/asm/arch-exynos/dwmmc.h
> +++ b/arch/arm/include/asm/arch-exynos/dwmmc.h
> @@ -27,10 +27,7 @@
>  #define DWMCI_SET_DRV_CLK(x)   ((x) << 16)
>  #define DWMCI_SET_DIV_RATIO(x) ((x) << 24)
>
> -int exynos_dwmci_init(u32 regbase, int bus_width, int index);
> -
> -static inline unsigned int exynos_dwmmc_init(int index, int bus_width)
> -{
> -       unsigned int base = samsung_get_base_mmc() + (0x10000 * index);
> -       return exynos_dwmci_init(base, bus_width, index);
> -}
> +#ifdef CONFIG_OF_CONTROL
> +int exynos_dwmmc_init(const void *blob);
> +#endif
> +int exynos_dwmci_add_port(int index, u32 regbase, int bus_width, u32 clksel);
> diff --git a/drivers/mmc/exynos_dw_mmc.c b/drivers/mmc/exynos_dw_mmc.c
> index 72a31b7..1d09e56 100644
> --- a/drivers/mmc/exynos_dw_mmc.c
> +++ b/drivers/mmc/exynos_dw_mmc.c
> @@ -19,39 +19,146 @@
>   */
>
>  #include <common.h>
> -#include <malloc.h>
>  #include <dwmmc.h>
> +#include <fdtdec.h>
> +#include <libfdt.h>
> +#include <malloc.h>
>  #include <asm/arch/dwmmc.h>
>  #include <asm/arch/clk.h>
> +#include <asm/arch/pinmux.h>
>
> -static char *EXYNOS_NAME = "EXYNOS DWMMC";
> +#define        DWMMC_MAX_CH_NUM                4
> +#define        DWMMC_MAX_FREQ                  52000000
> +#define        DWMMC_MIN_FREQ                  400000
> +#define        DWMMC_MMC0_CLKSEL_VAL           0x03030001
> +#define        DWMMC_MMC2_CLKSEL_VAL           0x03020001
>
> +/*
> + * Function used as callback function to initialise the
> + * CLKSEL register for every mmc channel.
> + */
>  static void exynos_dwmci_clksel(struct dwmci_host *host)
>  {
> -       u32 val;
> -       val = DWMCI_SET_SAMPLE_CLK(DWMCI_SHIFT_0) |
> -               DWMCI_SET_DRV_CLK(DWMCI_SHIFT_0) | DWMCI_SET_DIV_RATIO(0);
> +       dwmci_writel(host, DWMCI_CLKSEL, host->clksel_val);
> +}
>
> -       dwmci_writel(host, DWMCI_CLKSEL, val);
> +unsigned int exynos_dwmci_get_clk(int dev_index)
> +{
> +       return get_mmc_clk(dev_index);
>  }
>
> -int exynos_dwmci_init(u32 regbase, int bus_width, int index)
> +/*
> + * This function adds the mmc channel to be registered with mmc core.
> + * index -     mmc channel number.
> + * regbase -   register base address of mmc channel specified in 'index'.
> + * bus_width - operating bus width of mmc channel specified in 'index'.
> + * clksel -    value to be written into CLKSEL register in case of FDT.
> + *             NULL in case od non-FDT.
> + */
> +int exynos_dwmci_add_port(int index, u32 regbase, int bus_width, u32 clksel)
>  {
>         struct dwmci_host *host = NULL;
> +       unsigned int div;
> +       unsigned long freq, sclk;
>         host = malloc(sizeof(struct dwmci_host));
>         if (!host) {
>                 printf("dwmci_host malloc fail!\n");
>                 return 1;
>         }
> +       /* request mmc clock vlaue of 50MHz.  */
> +       freq = 50000000;

Should this be 52MHz?

> +       sclk = get_mmc_clk(index);
> +       div = DIV_ROUND_UP(sclk, freq);
> +       /* set the clock divisor for mmc */
> +       set_mmc_clk(index, div);
>
> -       host->name = EXYNOS_NAME;
> +       host->name = "EXYNOS DWMMC";
>         host->ioaddr = (void *)regbase;
>         host->buswidth = bus_width;
> +
> +       if (clksel)

{} around if() part since you have it for else.

> +               host->clksel_val = clksel;
> +       else {
> +               if (0 == index)
> +                       host->clksel_val = DWMMC_MMC0_CLKSEL_VAL;
> +               if (2 == index)
> +                       host->clksel_val = DWMMC_MMC2_CLKSEL_VAL;
> +       }
> +
>         host->clksel = exynos_dwmci_clksel;
>         host->dev_index = index;
> +       host->mmc_clk = exynos_dwmci_get_clk;
> +       /* Add the mmc channel to be registered with mmc core */
> +       if (add_dwmci(host, DWMMC_MAX_FREQ, DWMMC_MIN_FREQ)) {
> +               printf("dwmmc%d registration failed\n", index);

Should this be debug()?

> +               return -1;
> +       }
> +       return 0;
> +}
> +
> +#ifdef CONFIG_OF_CONTROL
> +int exynos_dwmmc_init(const void *blob)
> +{
> +       int index, bus_width;
> +       int node_list[DWMMC_MAX_CH_NUM];
> +       int err = 0, dev_id, flag, count, i;
> +       u32 clksel_val, base, timing[3];
> +
> +       count = fdtdec_find_aliases_for_id(blob, "mmc",
> +                               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;
>
> -       add_dwmci(host, 52000000, 400000);
> +               /* 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;
> +               }
> +
> +               clksel_val = (DWMCI_SET_SAMPLE_CLK(timing[0]) |
> +                               DWMCI_SET_DRV_CLK(timing[1]) |
> +                               DWMCI_SET_DIV_RATIO(timing[2]));
> +               /* Initialise each mmc channel */
> +               err = exynos_dwmci_add_port(index, base, bus_width, clksel_val);
> +               if (err)
> +                       debug("dwmmc Channel-%d init failed\n", index);
> +       }
>         return 0;
>  }
> -
> +#endif
> diff --git a/include/dwmmc.h b/include/dwmmc.h
> index c8b1d40..e142f3e 100644
> --- a/include/dwmmc.h
> +++ b/include/dwmmc.h
> @@ -123,6 +123,8 @@
>  #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 +146,7 @@ struct dwmci_host {
>         unsigned int bus_hz;
>         int dev_index;
>         int buswidth;
> +       u32 clksel_val;
>         u32 fifoth_val;
>         struct mmc *mmc;
>
> --
> 1.8.0
>

Regards,
Simon


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