Re: [PATCH v3 2/6] mmc: sdhci: Add support for "Tuning Error" interrupts

[Adrian Hunter <adrian.hunter@xxxxxxxxx>]

On 10/04/24 22:16, Hans de Goede wrote:
> From: Adrian Hunter <adrian.hunter@xxxxxxxxx>
> 
> Most Bay Trail devices do not enable UHS modes for the external sdcard slot
> the Lenovo Yoga Tablet 2 830 / 1050 and Lenovo Yoga Tablet 2 Pro 1380 (8",
> 10" and 13") models however do enable this.
> 
> Using a UHS cards in these tablets results in errors like this one:
> 
> [  225.272001] mmc2: Unexpected interrupt 0x04000000.
> [  225.272024] mmc2: sdhci: ============ SDHCI REGISTER DUMP ===========
> [  225.272034] mmc2: sdhci: Sys addr:  0x0712c400 | Version:  0x0000b502
> [  225.272044] mmc2: sdhci: Blk size:  0x00007200 | Blk cnt:  0x00000007
> [  225.272054] mmc2: sdhci: Argument:  0x00000000 | Trn mode: 0x00000023
> [  225.272064] mmc2: sdhci: Present:   0x01e20002 | Host ctl: 0x00000016
> [  225.272073] mmc2: sdhci: Power:     0x0000000f | Blk gap:  0x00000000
> [  225.272082] mmc2: sdhci: Wake-up:   0x00000000 | Clock:    0x00000107
> [  225.272092] mmc2: sdhci: Timeout:   0x0000000e | Int stat: 0x00000001
> [  225.272101] mmc2: sdhci: Int enab:  0x03ff000b | Sig enab: 0x03ff000b
> [  225.272110] mmc2: sdhci: ACmd stat: 0x00000000 | Slot int: 0x00000001
> [  225.272119] mmc2: sdhci: Caps:      0x076864b2 | Caps_1:   0x00000004
> [  225.272129] mmc2: sdhci: Cmd:       0x00000c1b | Max curr: 0x00000000
> [  225.272138] mmc2: sdhci: Resp[0]:   0x00000c00 | Resp[1]:  0x00000000
> [  225.272147] mmc2: sdhci: Resp[2]:   0x00000000 | Resp[3]:  0x00000900
> [  225.272155] mmc2: sdhci: Host ctl2: 0x0000000c
> [  225.272164] mmc2: sdhci: ADMA Err:  0x00000003 | ADMA Ptr: 0x0712c200
> [  225.272172] mmc2: sdhci: ============================================
> 
> which results in IO errors leading to issues accessing the sdcard.
> 
> 0x04000000 is a so-called "Tuning Error" which sofar the SDHCI driver
> does not support / enable. Modify the IRQ handler to process these.
> 
> This fixes UHS microsd cards not working with these tablets.
> 

Needs my SOB here:

Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>

> Link: https://lore.kernel.org/r/199bb4aa-c6b5-453e-be37-58bbf468800c@xxxxxxxxx
> Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
> ---
>  drivers/mmc/host/sdhci.c | 10 ++++++++--
>  drivers/mmc/host/sdhci.h |  3 ++-
>  2 files changed, 10 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index c79f73459915..746f4cf7ab03 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -3439,12 +3439,18 @@ static void sdhci_data_irq(struct sdhci_host *host, u32 intmask)
>  		host->data->error = -EILSEQ;
>  		if (!mmc_op_tuning(SDHCI_GET_CMD(sdhci_readw(host, SDHCI_COMMAND))))
>  			sdhci_err_stats_inc(host, DAT_CRC);
> -	} else if ((intmask & SDHCI_INT_DATA_CRC) &&
> +	} else if ((intmask & (SDHCI_INT_DATA_CRC | SDHCI_INT_TUNING_ERROR)) &&
>  		SDHCI_GET_CMD(sdhci_readw(host, SDHCI_COMMAND))
>  			!= MMC_BUS_TEST_R) {
>  		host->data->error = -EILSEQ;
>  		if (!mmc_op_tuning(SDHCI_GET_CMD(sdhci_readw(host, SDHCI_COMMAND))))
>  			sdhci_err_stats_inc(host, DAT_CRC);
> +		if (intmask & SDHCI_INT_TUNING_ERROR) {
> +			u16 ctrl2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
> +
> +			ctrl2 &= ~SDHCI_CTRL_TUNED_CLK;
> +			sdhci_writew(host, ctrl2, SDHCI_HOST_CONTROL2);
> +		}
>  	} else if (intmask & SDHCI_INT_ADMA_ERROR) {
>  		pr_err("%s: ADMA error: 0x%08x\n", mmc_hostname(host->mmc),
>  		       intmask);
> @@ -3979,7 +3985,7 @@ bool sdhci_cqe_irq(struct sdhci_host *host, u32 intmask, int *cmd_error,
>  	} else
>  		*cmd_error = 0;
>  
> -	if (intmask & (SDHCI_INT_DATA_END_BIT | SDHCI_INT_DATA_CRC)) {
> +	if (intmask & (SDHCI_INT_DATA_END_BIT | SDHCI_INT_DATA_CRC | SDHCI_INT_TUNING_ERROR)) {
>  		*data_error = -EILSEQ;
>  		if (!mmc_op_tuning(SDHCI_GET_CMD(sdhci_readw(host, SDHCI_COMMAND))))
>  			sdhci_err_stats_inc(host, DAT_CRC);
> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
> index a20864fc0641..957c7a917ffb 100644
> --- a/drivers/mmc/host/sdhci.h
> +++ b/drivers/mmc/host/sdhci.h
> @@ -158,6 +158,7 @@
>  #define  SDHCI_INT_BUS_POWER	0x00800000
>  #define  SDHCI_INT_AUTO_CMD_ERR	0x01000000
>  #define  SDHCI_INT_ADMA_ERROR	0x02000000
> +#define  SDHCI_INT_TUNING_ERROR	0x04000000
>  
>  #define  SDHCI_INT_NORMAL_MASK	0x00007FFF
>  #define  SDHCI_INT_ERROR_MASK	0xFFFF8000
> @@ -169,7 +170,7 @@
>  		SDHCI_INT_DATA_AVAIL | SDHCI_INT_SPACE_AVAIL | \
>  		SDHCI_INT_DATA_TIMEOUT | SDHCI_INT_DATA_CRC | \
>  		SDHCI_INT_DATA_END_BIT | SDHCI_INT_ADMA_ERROR | \
> -		SDHCI_INT_BLK_GAP)
> +		SDHCI_INT_BLK_GAP | SDHCI_INT_TUNING_ERROR)
>  #define SDHCI_INT_ALL_MASK	((unsigned int)-1)
>  
>  #define SDHCI_CQE_INT_ERR_MASK ( \