[U-Boot] [PATCH V8 4/9] EXYNOS5: DWMMC: Added FDT support for DWMMC

Amarendra Reddy amar.lavanuru at gmail.com
Tue Apr 23 06:33:42 CEST 2013


Hi Jaehoon,

Please find my response below

Thanks & Regards
Amarendra

On 23 April 2013 09:27, Jaehoon Chung <jh80.chung at samsung.com> wrote:

> On 04/16/2013 05:44 PM, Amarendra Reddy wrote:
> > Hi Jaehoon,
> >
> > Please find my response below.
> >
> > Thanks & Regards
> > Amarendra Reddy
> >
> > On 12 April 2013 16:50, Jaehoon Chung <jh80.chung at samsung.com> wrote:
> >
> >> On 04/10/2013 03:13 PM, Amarendra Reddy wrote:
> >>> Hi Jaehoon,
> >>>
> >>> Please find my responses below.
> >>>
> >>> Thanks & Regards
> >>> Amarendra Reddy
> >>>
> >>> On 9 April 2013 16:23, Jaehoon Chung <jh80.chung at samsung.com> wrote:
> >>>
> >>>> On 04/03/2013 11:08 PM, Amar 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>
> >>>>> ---
> >>>>> 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.
> >>>>>
> >>>>> Changes since V5:
> >>>>>       1)Updated in response to review comments and changed the mmc
> >> clock
> >>>> value
> >>>>>       from 50MHz to 52MHz.
> >>>>>
> >>>>> Changes since V6:
> >>>>>       No change.
> >>>>>
> >>>>> Changes since V7:
> >>>>>       No change.
> >>>>>
> >>>>>  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..4238dd9 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
> >>>> I known that CLKSEL's value is SoC specific.
> >>>> All exynos series are working fine? I didn't think so.
> >>>>
> >>>> Best Regards,
> >>>> Jaehoon Chung
> >>>>
> >>>
> >>> The above values of CLKSEL work fine for Exynos5 (5250 & 5410) and is
> >>> tested.
> >>>
> >>> The above CLKSEL values donot hold good for Exynos4 series. Exynos4 has
> >>> "Mobile Storage Host" with only one port.
> >>> But this file 'drivers/mmc/exynos_dw_mmc.c' is specific to Exynos5
> series
> >>> and gets compiled only when CONFIG_EXYNOS_DWMMC is defined.
> >> No, driver/mmc/exynos_dw_mmc.c isn't specific to Exynos5 series.
> >> We can use this controller at the exynos4.
> >> Then we need to consider how get the clksel value according to SoC.
> >>
> >> Best Regards,
> >> Jaehoon Chung
> >>
> >
> > OK. Then I shall add the macro for supporting exynos4 also as shown below
> > #define EXYNOS4_DWMMC_MMC0_CLKSEL_VAL           0x00000000 (reset value)
> > #define EXYNOS5_DWMMC_MMC0_CLKSEL_VAL           0x03030001
> > #define EXYNOS5_DWMMC_MMC2_CLKSEL_VAL           0x03020001
> >
> > In Exynos4, Mobile Storage Host has only one channel.
> >
> > The the below function will be updated as below
> > int exynos_dwmci_add_port(int index, u32 regbase, int bus_width, u32
> clksel)
> > {
> >  ......
> >  ......
> >
> >         if (clksel) {
> >                 host->clksel_val = clksel;
> >         } else {
> >                 if (0 == index) {
> >                         if(cpu_is_exynos5())
> >                                      host->clksel_val =
> > EXYNOS5_DWMMC_MMC0_CLKSEL_VAL;
> >                         else
> >                                      host->clksel_val =
> > EXYNOS4_DWMMC_MMC0_CLKSEL_VAL;      /* Exynos4 MSH has only one channel
> */
> >
> >                 }
> >
> >                 if (2 == index)
> >                         host->clksel_val = EXYNOS5_DWMMC_MMC2_CLKSEL_VAL;
> >         }
> >  ........
> >  ........
> > }
> >
> > Is it OK. Please comment on the above.
> Well...if you want to set the CLKSEL,i will modify for exynos4 in future.
> How about this? (I think you're only working for the exynos5)
>
> Ok fine, that will be really good. Hence right now I will not set CLKSEL
for exynos4 in the file 'drivers/mmc/exynos_dw_mmc.c'.

Best Regards,
> Jaehoon Chung
> >
> > Thanks & Regards
> > Amarendra Reddy
> >
> >>>
> >>>>
> >>>>> +/*
> >>>>> + * 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 52MHz.  */
> >>>>> +     freq = 52000000;
> >>>>> +     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) {
> >>>>> +             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)) {
> >>>>> +             debug("dwmmc%d registration failed\n", index);
> >>>>> +             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;
> >>>>>
> >>>>>
> >>>>
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> >>>
> >>>
> >>>
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> >>
> >
> >
> >
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