Chris,
Just tested the mod on brownstone. Works.
Philip
On May 24, 2011, at 6:14 PM, Philip Rakity wrote:
>
> resend
>
> Note: I cannot test test for a few days. Following Chris
> suggestion posting to list.
>
> version 2
> ---
> return -EINVAL when compare of ext_csd_fails
> combine two compare routines into one per suggestion
> from Chris.
>
> ---
> version 1
>
> CMD19 -- The offical way to validate bus widths from the
> JEDEC spec does not work on all platforms. Some platforms
> that use PCI/PCIe to connect their SD controllers are known
> to fail.
>
> If the quirk MMC_BUS_WIDTH_TEST is not defined we try
> to figure out the bus width by reading the ext_csd at different
> bus widths and compare this against the ext_csd read in 1 bit
> mode. If no ext_csd is available we default to 1 bit operations.
>
> Code has been tested on mmp2 against 8 bit eMMC and Transcend 2GB
> card that is known to not work in 4 bit mode. The physical
> pins on the card are not present to support 4 bit operation.
>
> Signed-off-by: Philip Rakity <prakity@xxxxxxxxxxx>
> ---
> drivers/mmc/core/mmc.c | 113 +++++++++++++++++++++++++++++++++++++++++++----
> 1 files changed, 103 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
> index baab027..6db91d6 100644
> --- a/drivers/mmc/core/mmc.c
> +++ b/drivers/mmc/core/mmc.c
> @@ -174,14 +174,17 @@ static int mmc_decode_csd(struct mmc_card *card)
> }
>
> /*
> - * Read and decode extended CSD.
> + * Read extended CSD.
> */
> -static int mmc_read_ext_csd(struct mmc_card *card)
> +static int mmc_get_ext_csd(struct mmc_card *card, u8 **new_ext_csd)
> {
> int err;
> u8 *ext_csd;
>
> BUG_ON(!card);
> + BUG_ON(!new_ext_csd);
> +
> + *new_ext_csd = NULL;
>
> if (card->csd.mmca_vsn < CSD_SPEC_VER_4)
> return 0;
> @@ -199,12 +202,15 @@ static int mmc_read_ext_csd(struct mmc_card *card)
>
> err = mmc_send_ext_csd(card, ext_csd);
> if (err) {
> + kfree(ext_csd);
> + *new_ext_csd = NULL;
> +
> /* If the host or the card can't do the switch,
> * fail more gracefully. */
> if ((err != -EINVAL)
> && (err != -ENOSYS)
> && (err != -EFAULT))
> - goto out;
> + return err;
>
> /*
> * High capacity cards should have this "magic" size
> @@ -222,9 +228,23 @@ static int mmc_read_ext_csd(struct mmc_card *card)
> mmc_hostname(card->host));
> err = 0;
> }
> + } else
> + *new_ext_csd = ext_csd;
>
> - goto out;
> - }
> + return err;
> +}
> +
> +/*
> + * Decode extended CSD.
> + */
> +static int mmc_read_ext_csd(struct mmc_card *card, u8 *ext_csd)
> +{
> + int err = 0;
> +
> + BUG_ON(!card);
> +
> + if (!ext_csd)
> + return 0;
>
> /* Version is coded in the CSD_STRUCTURE byte in the EXT_CSD register */
> if (card->csd.structure == 3) {
> @@ -372,8 +392,70 @@ static int mmc_read_ext_csd(struct mmc_card *card)
> card->erased_byte = 0x0;
>
> out:
> + return err;
> +}
> +
> +static inline void mmc_free_ext_csd(u8 *ext_csd)
> +{
> kfree(ext_csd);
> +}
> +
>
> +static int mmc_compare_ext_csds(struct mmc_card *card, u8 *ext_csd,
> + unsigned bus_width)
> +{
> + u8 *bw_ext_csd;
> + int err;
> +
> + err = mmc_get_ext_csd(card, &bw_ext_csd);
> + if (err)
> + return err;
> +
> + if ((ext_csd == NULL || bw_ext_csd == NULL)) {
> + if (bus_width != MMC_BUS_WIDTH_1)
> + err = -EINVAL;
> + goto out;
> + }
> +
> + if (bus_width == MMC_BUS_WIDTH_1)
> + goto out;
> +
> + /* only compare read only fields */
> +
> + err = (!(ext_csd[EXT_CSD_PARTITION_SUPPORT] ==
> + bw_ext_csd[EXT_CSD_PARTITION_SUPPORT]) &&
> + (ext_csd[EXT_CSD_ERASED_MEM_CONT] ==
> + bw_ext_csd[EXT_CSD_ERASED_MEM_CONT]) &&
> + (ext_csd[EXT_CSD_REV] ==
> + bw_ext_csd[EXT_CSD_REV]) &&
> + (ext_csd[EXT_CSD_STRUCTURE] ==
> + bw_ext_csd[EXT_CSD_STRUCTURE]) &&
> + (ext_csd[EXT_CSD_CARD_TYPE] ==
> + bw_ext_csd[EXT_CSD_CARD_TYPE]) &&
> + (ext_csd[EXT_CSD_S_A_TIMEOUT] ==
> + bw_ext_csd[EXT_CSD_S_A_TIMEOUT]) &&
> + (ext_csd[EXT_CSD_HC_WP_GRP_SIZE] ==
> + bw_ext_csd[EXT_CSD_HC_WP_GRP_SIZE]) &&
> + (ext_csd[EXT_CSD_ERASE_TIMEOUT_MULT] ==
> + bw_ext_csd[EXT_CSD_ERASE_TIMEOUT_MULT]) &&
> + (ext_csd[EXT_CSD_HC_ERASE_GRP_SIZE] ==
> + bw_ext_csd[EXT_CSD_HC_ERASE_GRP_SIZE]) &&
> + (ext_csd[EXT_CSD_SEC_TRIM_MULT] ==
> + bw_ext_csd[EXT_CSD_SEC_TRIM_MULT]) &&
> + (ext_csd[EXT_CSD_SEC_ERASE_MULT] ==
> + bw_ext_csd[EXT_CSD_SEC_ERASE_MULT]) &&
> + (ext_csd[EXT_CSD_SEC_FEATURE_SUPPORT] ==
> + bw_ext_csd[EXT_CSD_SEC_FEATURE_SUPPORT]) &&
> + (ext_csd[EXT_CSD_TRIM_MULT] ==
> + bw_ext_csd[EXT_CSD_TRIM_MULT]) &&
> + memcmp(&ext_csd[EXT_CSD_SEC_CNT],
> + &bw_ext_csd[EXT_CSD_SEC_CNT],
> + 4) != 0);
> + if (err)
> + err = -EINVAL;
> +
> +out:
> + mmc_free_ext_csd(bw_ext_csd);
> return err;
> }
>
> @@ -438,6 +520,7 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
> u32 cid[4];
> unsigned int max_dtr;
> u32 rocr;
> + u8 *ext_csd = NULL;
>
> BUG_ON(!host);
> WARN_ON(!host->claimed);
> @@ -536,7 +619,11 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
> /*
> * Fetch and process extended CSD.
> */
> - err = mmc_read_ext_csd(card);
> +
> + err = mmc_get_ext_csd(card, &ext_csd);
> + if (err)
> + goto free_card;
> + err = mmc_read_ext_csd(card, ext_csd);
> if (err)
> goto free_card;
>
> @@ -676,14 +763,18 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
> 0);
> if (!err) {
> mmc_set_bus_width(card->host, bus_width);
> +
> /*
> * If controller can't handle bus width test,
> - * use the highest bus width to maintain
> - * compatibility with previous MMC behavior.
> + * compare ext_csd previously read in 1 bit mode
> + * against ext_csd at new bus width
> */
> if (!(host->caps & MMC_CAP_BUS_WIDTH_TEST))
> - break;
> - err = mmc_bus_test(card, bus_width);
> + err = mmc_compare_ext_csds(card,
> + ext_csd,
> + bus_width);
> + else
> + err = mmc_bus_test(card, bus_width);
> if (!err)
> break;
> }
> @@ -730,12 +821,14 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
> if (!oldcard)
> host->card = card;
>
> + mmc_free_ext_csd(ext_csd);
> return 0;
>
> free_card:
> if (!oldcard)
> mmc_remove_card(card);
> err:
> + mmc_free_ext_csd(ext_csd);
>
> return err;
> }
> --
> 1.7.0.4
>
>
>
> On May 23, 2011, at 9:42 PM, Chris Ball wrote:
>
>> Hi Philip,
>>
>> On Sun, May 22 2011, Philip Rakity wrote:
>>> diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
>>> index baab027..6db91d6 100644
>>> --- a/drivers/mmc/core/mmc.c
>>> +++ b/drivers/mmc/core/mmc.c
>>> @@ -174,14 +174,17 @@ static int mmc_decode_csd(struct mmc_card *card)
>>> }
>>>
>>> /*
>>> - * Read and decode extended CSD.
>>> + * Read extended CSD.
>>> */
>>> -static int mmc_read_ext_csd(struct mmc_card *card)
>>> +static int mmc_read_ext_csd(struct mmc_card *card, u8 *ext_csd)
>>
>> This one doesn't work -- you're missing the half of the patch that hooks
>> up the rest of mmc.c to the new code, which was in v1. As-is, we get:
>>
>> drivers/mmc/core/mmc.c: In function ‘mmc_init_card’:
>> drivers/mmc/core/mmc.c:621:3: error: too few arguments to function ‘mmc_read_ext_csd’
>> drivers/mmc/core/mmc.c:240:12: note: declared here
>> drivers/mmc/core/mmc.c: At top level:
>> drivers/mmc/core/mmc.c:404:12: warning: ‘mmc_compare_ext_csds’ defined but not used [-Wunused-function]
>>
>> - Chris.
>> --
>> Chris Ball <cjb@xxxxxxxxxx> <http://printf.net/>
>> One Laptop Per Child
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
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>
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