Hi

On 10/17/2011 09:46 AM, Jaehoon Chung wrote:
> Hi James.
> 
> On 10/17/2011 05:27 PM, James Hogan wrote:
> 
>> Hi,
>>
>> On 10/17/2011 08:05 AM, Jaehoon Chung wrote:
>>> In dw_mmc 2.40a spec, Data register's offset is changed.
>>> Now we used Data register offset is 0x100. but if somebody use 2.40a
>>> controller, must use 0x200 for Data register.
>>>
>>> This patch is added version-id checking point and using SDMMC_DATA(x)
>>> instead of SDMMC_DATA. (assume 2.40a is the latest version)
>>>
>>> Signed-off-by: Jaehoon Chung <[email protected]>
>>> Signed-off-by: Kyungmin Park <[email protected]>
>>> ---
>>>  drivers/mmc/host/dw_mmc.c  |   66 
>>> ++++++++++++++++++++++++++++++--------------
>>>  drivers/mmc/host/dw_mmc.h  |   10 ++++++-
>>>  include/linux/mmc/dw_mmc.h |    2 +
>>>  3 files changed, 56 insertions(+), 22 deletions(-)
>>>
>>> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
>>> index 701f14e..3aaeb08 100644
>>> --- a/drivers/mmc/host/dw_mmc.c
>>> +++ b/drivers/mmc/host/dw_mmc.c
>>> @@ -1043,7 +1043,8 @@ static void dw_mci_push_data16(struct dw_mci *host, 
>>> void *buf, int cnt)
>>>             buf += len;
>>>             cnt -= len;
>>>             if (!sg_next(host->sg) || host->part_buf_count == 2) {
>>> -                   mci_writew(host, DATA, host->part_buf16);
>>> +                   mci_writew(host, DATA(host->data_offset),
>>> +                                   host->part_buf16);
>>>                     host->part_buf_count = 0;
>>>             }
>>>     }
>>
>> I really think it would be more concise to just have something like this:
>> mci_writew(host, host->data_offset, host->part_buf16);
>> ...
>>
>>> +#define DATA_OFFSET                0
>>> +#define DATA_240A_OFFSET   0x100
>>
>> and then have these as register positions like the other #defines, e.g.
>> #define SDMMC_DATA      0x100
>> #define SDMMC_DATA_240A 0x200
>>
> 
> 
> Sorry, if change your suggestion, how do you control SDMMC_##reg?
> mci_readl(dev, reg) __raw_readl(dev->regs + SDMMC_##reg)

Ah ok, sorry. I see what you mean now. I'd forgotton the mci_readl macro
did that!

I suppose there's a couple of ways that you could avoid the offset from
0x100.

1) could define a register macro which takes a raw offset:
#define SDMMC_RAW(x)            (x)
mci_writew(host, RAW(host->data_offset), host->part_buf16);

2) could define the DATA register macro which takes a struct dw_mci* as
an argument:
#define SDMMC_DATA(HOST)        ((HOST)->data_offset)
mci_writew(host, DATA(host), host->part_buf16);

I don't have a strong preference between these.

Thanks
James

> 
>>> @@ -1952,6 +1964,18 @@ static int dw_mci_probe(struct platform_device *pdev)
>>>     }
>>>  
>>>     /*
>>> +    * In 2.40a spec, Data offset is changed.
>>> +    * Need to check the version-id and set data-offset for DATA register.
>>> +    */
>>> +   host->verid = SDMMC_GET_VERID(mci_readl(host, VERID));
>>> +   dev_info(&pdev->dev, "Version ID is %04x\n", host->verid);
>>> +
>>> +   if (host->verid < DW_MMC_240A)
>>> +           host->data_offset = DATA_OFFSET;
>>> +   else
>>> +           host->data_offset = DATA_240A_OFFSET;
>>> +
>>> +   /*
>>>      * Enable interrupts for command done, data over, data empty, card det,
>>>      * receive ready and error such as transmit, receive timeout, crc error
>>>      */
>>> diff --git a/drivers/mmc/host/dw_mmc.h b/drivers/mmc/host/dw_mmc.h
>>> index bfa3c1c..965fd19 100644
>>> --- a/drivers/mmc/host/dw_mmc.h
>>> +++ b/drivers/mmc/host/dw_mmc.h
>>> @@ -14,6 +14,8 @@
>>>  #ifndef _DW_MMC_H_
>>>  #define _DW_MMC_H_
>>>  
>>> +#define DW_MMC_240A                0x240a
>>> +
>>>  #define SDMMC_CTRL         0x000
>>>  #define SDMMC_PWREN                0x004
>>>  #define SDMMC_CLKDIV               0x008
>>> @@ -51,7 +53,11 @@
>>>  #define SDMMC_IDINTEN              0x090
>>>  #define SDMMC_DSCADDR              0x094
>>>  #define SDMMC_BUFADDR              0x098
>>> -#define SDMMC_DATA         0x100
>>> +#define SDMMC_DATA(x)              (0x100 + (x))
>>> +
>>> +/* Data offset is difference according to Verision */
>>
>> should that be "version"?
> 
> Typo..should fix that.
> 
>>
>>> +#define DATA_OFFSET                0
>>> +#define DATA_240A_OFFSET   0x100
>>>  
>>>  /* shift bit field */
>>>  #define _SBF(f, v)         ((v) << (f))
>>> @@ -130,6 +136,8 @@
>>>  #define SDMMC_IDMAC_ENABLE         BIT(7)
>>>  #define SDMMC_IDMAC_FB                     BIT(1)
>>>  #define SDMMC_IDMAC_SWRESET                BIT(0)
>>> +/* Version ID register define */
>>> +#define SDMMC_GET_VERID(x)         ((x) & 0xFFFF)
>>>  
>>>  /* Register access macros */
>>>  #define mci_readl(dev, reg)                        \
>>> diff --git a/include/linux/mmc/dw_mmc.h b/include/linux/mmc/dw_mmc.h
>>> index 6b46819..6928e29 100644
>>> --- a/include/linux/mmc/dw_mmc.h
>>> +++ b/include/linux/mmc/dw_mmc.h
>>> @@ -147,6 +147,8 @@ struct dw_mci {
>>>     u32                     current_speed;
>>>     u32                     num_slots;
>>>     u32                     fifoth_val;
>>> +   u16                     verid;
>>> +   u16                     data_offset;
>>>     struct platform_device  *pdev;
>>>     struct dw_mci_board     *pdata;
>>>     struct dw_mci_slot      *slot[MAX_MCI_SLOTS];
>>
>> The kerneldoc comment above struct dw_mci should be updated to describe
>> the new fields.
> 
> I will add the comment for new fields,
> 
> Best Regards,
> Jaehoon Chung
> 
>>
> 
>> Other than that it looks good to me.
>>
>> Thanks
>> James
>>
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>>
> 
> 

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