[PATCH] mmc: core: add core-level function for sending tuning commands
Ulf Hansson
ulf.hansson at linaro.org
Tue Nov 25 02:32:17 PST 2014
On 25 November 2014 at 04:19, Barry Song <21cnbao at gmail.com> wrote:
> 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);
>
Looks good!
Kind regards
Uffe
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