Re: [PATCH v4 0/4] StarFive's SDIO/eMMC driver support

[William Qiu <william.qiu@starfivetech.com>]

On 2023/2/15 20:37, Ulf Hansson wrote:
> On Wed, 15 Feb 2023 at 12:32, William Qiu <william.qiu@starfivetech.com> wrote:
>>
>> Hi,
>>
>> This patchset adds initial rudimentary support for the StarFive
>> designware mobile storage host controller driver. And this driver will
>> be used in StarFive's VisionFive 2 board. The main purpose of adding
>> this driver is to accommodate the ultra-high speed mode of eMMC.
>>
>> The last patch should be applied after the patchset [1]:
>> [1] https://lore.kernel.org/all/20221220011247.35560-1-hal.feng@starfivetech.com/
>>
>> Changes v3->v4:
>> - Added documentation to describe StarFive System Controller Registers.
>> - Added aon_syscon and stg_syscon node.
>> - Fixed some checkpatch errors/warnings.
>>
>> Changes v2->v3:
>> - Wraped commit message according to Linux coding style.
>> - Rephrased the description of the patches.
>> - Changed the description of syscon regsiter.
>> - Dropped redundant properties.
>>
>> Changes v1->v2:
>> - Renamed the dt-binding 'starfive,jh7110-sdio.yaml' to 'starfive,jh7110-mmc.yaml'.
>> - Changed the type of 'starfive,syscon' and modify its description.
>> - Deleted unused head files like '#include <linux/gpio.h>'.
>> - Added comment for the 'rise_point' and 'fall_point'.
>> - Changed the API 'num_caps' to 'common_caps'.
>> - Changed the node name 'sys_syscon' to 'syscon'.
>> - Changed the node name 'sdio' to 'mmc'.
>>
>> The patch series is based on v6.1.
>>
>> William Qiu (4):
>>   dt-bindings: mmc: Add StarFive MMC module
>>   mmc: starfive: Add sdio/emmc driver support
>>   riscv: dts: starfive: Add mmc node
>>   dt-bindings: syscon: Add StarFive syscon doc
>>
>>  .../bindings/mmc/starfive,jh7110-mmc.yaml     |  77 ++++++++
>>  .../bindings/soc/starfive/jh7110-syscon.yaml  |  51 +++++
>>  MAINTAINERS                                   |  11 ++
>>  .../jh7110-starfive-visionfive-2.dtsi         |  23 +++
>>  arch/riscv/boot/dts/starfive/jh7110.dtsi      |  47 +++++
>>  drivers/mmc/host/Kconfig                      |  10 +
>>  drivers/mmc/host/Makefile                     |   1 +
>>  drivers/mmc/host/dw_mmc-starfive.c            | 186 ++++++++++++++++++
>>  8 files changed, 406 insertions(+)
>>  create mode 100644 Documentation/devicetree/bindings/mmc/starfive,jh7110-mmc.yaml
>>  create mode 100644 Documentation/devicetree/bindings/soc/starfive/jh7110-syscon.yaml
>>  create mode 100644 drivers/mmc/host/dw_mmc-starfive.c
>>
> 
> I have dropped the v3 patches and applied patch1 and patch2 from the
> v4 series instead, for my next branch, thanks!
> 
> Kind regards
> Uffe

Hi Uffe,

Sorry to bother you.But I found a bug that in drivers/mmc/host/dw_mmc-starfive.c:

    47 static int dw_mci_starfive_execute_tuning(struct dw_mci_slot *slot,
    48                                              u32 opcode)
    49 {
    50         static const int grade  = MAX_DELAY_CHAIN;
    51         struct dw_mci *host = slot->host;
    52         struct starfive_priv *priv = host->priv;
    53         int rise_point = -1, fall_point = -1;
    54         int err, prev_err;
    55         int i;
    56         bool found = 0;
    57         u32 regval;
    58 
    59         /*
    60          * Use grade as the max delay chain, and use the rise_point and
    61          * fall_point to ensure the best sampling point of a data input
    62          * signals.
    63          */
    64         for (i = 0; i < grade; i++) {
    65                 regval = i << priv->syscon_shift;
    66                 err = regmap_update_bits(priv->reg_syscon, priv->syscon_offset,
    67                                                 priv->syscon_mask, regval);
    68                 if (err)
    69                         return err;
    70                 mci_writel(host, RINTSTS, ALL_INT_CLR);
    71 
    72                 err = mmc_send_tuning(slot->mmc, opcode, NULL);
    73                 if (!err)
    74                         found = 1;
    75 
    76                 if (i > 0) {
--> 77                         if (err && !prev_err)

prev_err was never initialized to zero.

So I'm here to ask for your suggestion, should I send a new version
to fix it or send you a patch with a fixes tag?

Best regards
William