[PATCH] mmc: core: add core-level function for sending tuning commands
Barry Song
21cnbao at gmail.com
Mon Nov 24 19:19:26 PST 2014
2014-11-24 19:44 GMT+08:00 Ulf Hansson <ulf.hansson at linaro.org>:
> On 21 November 2014 at 15:46, Barry Song <21cnbao at gmail.com> wrote:
>> From: Minda Chen <Minda.Chen at csr.com>
>>
>> According to the SD card spec, Add a manual tuning command function
>> for SDR104/HS200 by sending command 19 or command 21 to read data
>> and compare with the tuning block pattern.
>>
>> this patch will help to decrease some platform private codes in
>> SDHCI platform_execute_tuning() callbacks.
>>
>> Signed-off-by: Minda Chen <Minda.Chen at csr.com>
>> Signed-off-by: Barry Song <Baohua.Song at csr.com>
>> ---
>> drivers/mmc/core/mmc_ops.c | 65 ++++++++++++++++++++++++++++++++++++++++++++++
>> include/linux/mmc/core.h | 1 +
>> 2 files changed, 66 insertions(+)
>>
>> diff --git a/drivers/mmc/core/mmc_ops.c b/drivers/mmc/core/mmc_ops.c
>> index 7911e05..ecc7789 100644
>> --- a/drivers/mmc/core/mmc_ops.c
>> +++ b/drivers/mmc/core/mmc_ops.c
>> @@ -543,6 +543,71 @@ int mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value,
>> }
>> EXPORT_SYMBOL_GPL(mmc_switch);
>>
>> +int mmc_send_tuning(struct mmc_card *card, u32 opcode)
>> +{
>> + struct mmc_request mrq = {NULL};
>> + struct mmc_command cmd = {0};
>> + struct mmc_data data = {0};
>> + struct scatterlist sg;
>> + struct mmc_host *mmc = card->host;
>> + struct mmc_ios *ios = &mmc->ios;
>> + const u8 *tuning_block_pattern;
>> + int size, err = 0;
>> + u8 *data_buf;
>> +
>> + if (opcode == MMC_SEND_TUNING_BLOCK_HS200) {
>
> I don't think we need to care about the opcode. Let's just check the bus_width.
>
>> + if (ios->bus_width == MMC_BUS_WIDTH_8) {
>> + tuning_block_pattern = tuning_blk_pattern_8bit;
>> + size = sizeof(tuning_blk_pattern_8bit);
>> + } else if (ios->bus_width == MMC_BUS_WIDTH_4) {
>> + tuning_block_pattern = tuning_blk_pattern_4bit;
>> + size = sizeof(tuning_blk_pattern_4bit);
>> + } else
>> + return -EINVAL;
>> + } else if (opcode == MMC_SEND_TUNING_BLOCK) {
>> + tuning_block_pattern = tuning_blk_pattern_4bit;
>> + size = sizeof(tuning_blk_pattern_4bit);
>> + } else
>> + return -EINVAL;
>> +
>> + data_buf = kmalloc(size, GFP_KERNEL);
>
> You should use kzalloc() to get the zeroed buffer you want.
>
>> + if (!data_buf)
>> + return -ENOMEM;
>> +
>> + mrq.cmd = &cmd;
>> + mrq.data = &data;
>> +
>> + cmd.opcode = opcode;
>> + cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
>> +
>> + data.blksz = size;
>> + data.blocks = 1;
>> + data.flags = MMC_DATA_READ;
>
> These needs to be assigned as well:
>
> data.sg = &sg;
> data.sg_len = 1;
>
>> +
>> + mmc_set_data_timeout(&data, card);
>
> mmc_set_data_timeout() doesn't handle CMD21/19.
>
> The specs tells us about 40 commands should be executed within 150ms.
> I would pick a value of 150ms, just to be sure we are inside that
> range. Also, assign "data->timeout_ns" here, instead of relying on
> mmc_set_data_timeout().
>
>> + sg_init_one(&sg, data_buf, size);
>> + memset(data_buf, 0, size);
>> + mmc_wait_for_req(mmc, &mrq);
>> +
>> + if (cmd.error) {
>> + err = cmd.error;
>> + goto out;
>> + }
>> +
>> + if (data.error) {
>> + err = data.error;
>> + goto out;
>> + }
>> +
>> + if (memcmp(data_buf, tuning_block_pattern, size))
>> + err = -EIO;
>> +
>> +out:
>> + kfree(data_buf);
>> + return err;
>> +}
>> +EXPORT_SYMBOL_GPL(mmc_send_tuning);
>> +
>> static int
>> mmc_send_bus_test(struct mmc_card *card, struct mmc_host *host, u8 opcode,
>> u8 len)
>> diff --git a/include/linux/mmc/core.h b/include/linux/mmc/core.h
>> index f206e29..82a0119 100644
>> --- a/include/linux/mmc/core.h
>> +++ b/include/linux/mmc/core.h
>> @@ -154,6 +154,7 @@ extern void mmc_start_bkops(struct mmc_card *card, bool from_exception);
>> extern int __mmc_switch(struct mmc_card *, u8, u8, u8, unsigned int, bool,
>> bool, bool);
>> extern int mmc_switch(struct mmc_card *, u8, u8, u8, unsigned int);
>> +extern int mmc_send_tuning(struct mmc_card *, u32);
>> extern int mmc_send_ext_csd(struct mmc_card *card, u8 *ext_csd);
>>
>> #define MMC_ERASE_ARG 0x00000000
>> --
>> 2.1.1
>>
What about?
546 int mmc_send_tuning(struct mmc_card *card)
547 {
548 struct mmc_request mrq = {NULL};
549 struct mmc_command cmd = {0};
550 struct mmc_data data = {0};
551 struct scatterlist sg;
552 struct mmc_host *mmc = card->host;
553 struct mmc_ios *ios = &mmc->ios;
554 const u8 *tuning_block_pattern;
555 int size, err = 0;
556 u8 *data_buf;
557 u32 opcode;
558
559 if (ios->bus_width == MMC_BUS_WIDTH_8) {
560 tuning_block_pattern = tuning_blk_pattern_8bit;
561 size = sizeof(tuning_blk_pattern_8bit);
562 opcode = MMC_SEND_TUNING_BLOCK_HS200;
563 } else if (ios->bus_width == MMC_BUS_WIDTH_4) {
564 tuning_block_pattern = tuning_blk_pattern_4bit;
565 size = sizeof(tuning_blk_pattern_4bit);
566 opcode = MMC_SEND_TUNING_BLOCK;
567 } else
568 return -EINVAL;
569
570 data_buf = kzalloc(size, GFP_KERNEL);
571 if (!data_buf)
572 return -ENOMEM;
573
574 mrq.cmd = &cmd;
575 mrq.data = &data;
576
577 cmd.opcode = opcode;
578 cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
579
580 data.blksz = size;
581 data.blocks = 1;
582 data.flags = MMC_DATA_READ;
583
584 /*
585 * According to the tuning specs, Tuning process
586 * is normally shorter 40 executions of CMD19,
587 * and timeout value should be shorter than 150 ms
588 */
589 data.timeout_ns = 150 * NSEC_PER_MSEC;
590
591 data.sg = &sg;
592 data.sg_len = 1;
593 sg_init_one(&sg, data_buf, size);
594
595 mmc_wait_for_req(mmc, &mrq);
596
597 if (cmd.error) {
598 err = cmd.error;
599 goto out;
600 }
601
602 if (data.error) {
603 err = data.error;
604 goto out;
605 }
606
607 if (memcmp(data_buf, tuning_block_pattern, size))
608 err = -EIO;
609
610 out:
611 kfree(data_buf);
612 return err;
613 }
614 EXPORT_SYMBOL_GPL(mmc_send_tuning);
>
> Kind regards
> Uffe
-barry
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