On 20/02/2024 08:37, Marek Vasut wrote:
Do not access SCC when sending commands during tuning operation as that will disrupt the tuning operation. The tuning operation is adjusting the SCC settings itself in execute_tuning callback.
When renesas_sdhi_execute_tuning() is called by the MMC core code, a loop which consists of renesas_sdhi_prepare_tuning(), mmc_send_tuning() and renesas_sdhi_compare_scc_data() iterates over each SCC tuning tap.
The renesas_sdhi_prepare_tuning() configures the SCC tuning tap number into hardware, mmc_send_tuning() triggers transfer of tuning block which depends on the bus mode for which the bus is currently being tuned, this information is supplied by the MMC core code, and finally renesas_sdhi_compare_scc_data() tests the received tuning block for validity.
Because renesas_sdhi_prepare_tuning() configures the SCC tuning tap into the hardware to fit the tuning operation, mmc_send_tuning() which triggers command transfer using renesas_sdhi_send_cmd() must not manipulate with the SCC in any way. Currently renesas_sdhi_send_cmd() does unconditionally call renesas_sdhi_check_scc_error(), which may adjust the SCC tuning tap position by writing RENESAS_SDHI_SCC_TAPSET, which would overwrite the required tuning configuration set by renesas_sdhi_prepare_tuning() and disrupt the tuning operation.
Fix this by skipping the renesas_sdhi_check_scc_error() call in case the MMC subsystem is in tuning state. This way, the SCC settings are left unmodified by command transfer during tuning operation.
Signed-off-by: Marek Vasut marek.vasut+renesas@mailbox.org
Cc: Hai Pham hai.pham.ud@renesas.com Cc: Jaehoon Chung jh80.chung@samsung.com Cc: Nobuhiro Iwamatsu iwamatsu@nigauri.org Cc: Paul Barker paul.barker.ct@bp.renesas.com Cc: Peng Fan peng.fan@nxp.com Cc: Sean Anderson seanga2@gmail.com Cc: Tom Rini trini@konsulko.com Cc: Yoshihiro Shimoda yoshihiro.shimoda.uh@renesas.com
drivers/mmc/renesas-sdhi.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/mmc/renesas-sdhi.c b/drivers/mmc/renesas-sdhi.c index 9770b6bb5e1..316b75b35fe 100644 --- a/drivers/mmc/renesas-sdhi.c +++ b/drivers/mmc/renesas-sdhi.c @@ -798,9 +798,12 @@ static int renesas_sdhi_send_cmd(struct udevice *dev, struct mmc_cmd *cmd, #if CONFIG_IS_ENABLED(MMC_UHS_SUPPORT) || \ CONFIG_IS_ENABLED(MMC_HS200_SUPPORT) || \ CONFIG_IS_ENABLED(MMC_HS400_SUPPORT)
- struct mmc_uclass_priv *upriv = dev_get_uclass_priv(dev); struct tmio_sd_priv *priv = dev_get_priv(dev);
- struct mmc *mmc = upriv->mmc;
- renesas_sdhi_check_scc_error(dev);
if (!mmc->tuning)
renesas_sdhi_check_scc_error(dev);if (cmd->cmdidx == MMC_CMD_SEND_STATUS) renesas_sdhi_adjust_hs400_mode_enable(priv);
Reviewed-by: Paul Barker paul.barker.ct@bp.renesas.com Tested-by: Paul Barker paul.barker.ct@bp.renesas.com (tested on RZ/G2L with commit ad50a8151387 from https://source.denx.de/u-boot/custodians/u-boot-sh)